1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.2
8 ** GDB values in Python are now callable if the value represents a
9 function. For example, if 'some_value' represents a function that
10 takes two integer parameters and returns a value, you can call
11 that function like so:
13 result = some_value (10,20)
15 ** Module gdb.types has been added.
16 It contains a collection of utilities for working with gdb.Types objects:
17 get_basic_type, has_field, make_enum_dict.
19 ** Module gdb.printing has been added.
20 It contains utilities for writing and registering pretty-printers.
21 New classes: PrettyPrinter, SubPrettyPrinter,
22 RegexpCollectionPrettyPrinter.
23 New function: register_pretty_printer.
25 ** New commands "info pretty-printers", "enable pretty-printer" and
26 "disable pretty-printer" have been added.
30 ** GDB now puts template parameters in scope when debugging in an
31 instantiation. For example, if you have:
33 template<int X> int func (void) { return X; }
35 then if you step into func<5>, "print X" will show "5". This
36 feature requires proper debuginfo support from the compiler; it
39 * GDB now has some support for using labels in the program's source in
40 linespecs. For instance, you can use "advance label" to continue
43 * GDB now has support for reading and writing a new .gdb_index
44 section. This section holds a fast index of DWARF debugging
45 information and can be used to greatly speed up GDB startup and
46 operation. See the documentation for `save gdb-index' for details.
48 * The "watch" command now accepts an optional "-location" argument.
49 When used, this causes GDB to watch the memory referred to by the
50 expression. Such a watchpoint is never deleted due to it going out
53 * GDB now supports thread debugging of core dumps on GNU/Linux.
55 GDB now activates thread debugging using the libthread_db library
56 when debugging GNU/Linux core dumps, similarly to when debugging
57 live processes. As a result, when debugging a core dump file, GDB
58 is now able to display pthread_t ids of threads. For example, "info
59 threads" shows the same output as when debugging the process when it
60 was live. In earlier releases, you'd see something like this:
63 * 1 LWP 6780 main () at main.c:10
65 While now you see this:
68 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
70 It is also now possible to inspect TLS variables when debugging core
73 When debugging a core dump generated on a machine other than the one
74 used to run GDB, you may need to point GDB at the correct
75 libthread_db library with the "set libthread-db-search-path"
76 command. See the user manual for more details on this command.
78 * New features in the GDB remote stub, GDBserver
80 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
81 and i686 LynxOS (version 5.x).
83 * Ada task switching is now supported on sparc-elf targets when
84 debugging a program using the Ravenscar Profile. For more information,
85 see the "Tasking Support when using the Ravenscar Profile" section
86 in the GDB user manual.
88 * Guile support was removed.
90 *** Changes in GDB 7.2
92 * Shared library support for remote targets by default
94 When GDB is configured for a generic, non-OS specific target, like
95 for example, --target=arm-eabi or one of the many *-*-elf targets,
96 GDB now queries remote stubs for loaded shared libraries using the
97 `qXfer:libraries:read' packet. Previously, shared library support
98 was always disabled for such configurations.
102 ** Argument Dependent Lookup (ADL)
104 In C++ ADL lookup directs function search to the namespaces of its
105 arguments even if the namespace has not been imported.
115 Here the compiler will search for `foo' in the namespace of 'b'
116 and find A::foo. GDB now supports this. This construct is commonly
117 used in the Standard Template Library for operators.
119 ** Improved User Defined Operator Support
121 In addition to member operators, GDB now supports lookup of operators
122 defined in a namespace and imported with a `using' directive, operators
123 defined in the global scope, operators imported implicitly from an
124 anonymous namespace, and the ADL operators mentioned in the previous
126 GDB now also supports proper overload resolution for all the previously
127 mentioned flavors of operators.
129 ** static const class members
131 Printing of static const class members that are initialized in the
132 class definition has been fixed.
134 * Windows Thread Information Block access.
136 On Windows targets, GDB now supports displaying the Windows Thread
137 Information Block (TIB) structure. This structure is visible either
138 by using the new command `info w32 thread-information-block' or, by
139 dereferencing the new convenience variable named `$_tlb', a
140 thread-specific pointer to the TIB. This feature is also supported
141 when remote debugging using GDBserver.
145 Static tracepoints are calls in the user program into a tracing
146 library. One such library is a port of the LTTng kernel tracer to
147 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
148 When debugging with GDBserver, GDB now supports combining the GDB
149 tracepoint machinery with such libraries. For example: the user can
150 use GDB to probe a static tracepoint marker (a call from the user
151 program into the tracing library) with the new "strace" command (see
152 "New commands" below). This creates a "static tracepoint" in the
153 breakpoint list, that can be manipulated with the same feature set
154 as fast and regular tracepoints. E.g., collect registers, local and
155 global variables, collect trace state variables, and define
156 tracepoint conditions. In addition, the user can collect extra
157 static tracepoint marker specific data, by collecting the new
158 $_sdata internal variable. When analyzing the trace buffer, you can
159 inspect $_sdata like any other variable available to GDB. For more
160 information, see the "Tracepoints" chapter in GDB user manual. New
161 remote packets have been defined to support static tracepoints, see
162 the "New remote packets" section below.
164 * Better reconstruction of tracepoints after disconnected tracing
166 GDB will attempt to download the original source form of tracepoint
167 definitions when starting a trace run, and then will upload these
168 upon reconnection to the target, resulting in a more accurate
169 reconstruction of the tracepoints that are in use on the target.
173 You can now exercise direct control over the ways that GDB can
174 affect your program. For instance, you can disallow the setting of
175 breakpoints, so that the program can run continuously (assuming
176 non-stop mode). In addition, the "observer" variable is available
177 to switch all of the different controls; in observer mode, GDB
178 cannot affect the target's behavior at all, which is useful for
179 tasks like diagnosing live systems in the field.
181 * The new convenience variable $_thread holds the number of the
188 Return the address of the Windows Thread Information Block of a given thread.
192 In response to several of the tracepoint packets, the target may now
193 also respond with a number of intermediate `qRelocInsn' request
194 packets before the final result packet, to have GDB handle
195 relocating an instruction to execute at a different address. This
196 is particularly useful for stubs that support fast tracepoints. GDB
197 reports support for this feature in the qSupported packet.
201 List static tracepoint markers in the target program.
205 List static tracepoint markers at a given address in the target
208 qXfer:statictrace:read
210 Read the static trace data collected (by a `collect $_sdata'
211 tracepoint action). The remote stub reports support for this packet
212 to gdb's qSupported query.
216 Send the current settings of GDB's permission flags.
220 Send part of the source (textual) form of a tracepoint definition,
221 which includes location, conditional, and action list.
223 * The source command now accepts a -s option to force searching for the
224 script in the source search path even if the script name specifies
227 * New features in the GDB remote stub, GDBserver
229 - GDBserver now support tracepoints (including fast tracepoints, and
230 static tracepoints). The feature is currently supported by the
231 i386-linux and amd64-linux builds. See the "Tracepoints support
232 in gdbserver" section in the manual for more information.
234 GDBserver JIT compiles the tracepoint's conditional agent
235 expression bytecode into native code whenever possible for low
236 overhead dynamic tracepoints conditionals. For such tracepoints,
237 an expression that examines program state is evaluated when the
238 tracepoint is reached, in order to determine whether to capture
239 trace data. If the condition is simple and false, processing the
240 tracepoint finishes very quickly and no data is gathered.
242 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
243 for static tracepoints support.
245 - GDBserver now supports x86_64 Windows 64-bit debugging.
247 * GDB now sends xmlRegisters= in qSupported packet to indicate that
248 it understands register description.
250 * The --batch flag now disables pagination and queries.
252 * X86 general purpose registers
254 GDB now supports reading/writing byte, word and double-word x86
255 general purpose registers directly. This means you can use, say,
256 $ah or $ax to refer, respectively, to the byte register AH and
257 16-bit word register AX that are actually portions of the 32-bit
258 register EAX or 64-bit register RAX.
260 * The `commands' command now accepts a range of breakpoints to modify.
261 A plain `commands' following a command that creates multiple
262 breakpoints affects all the breakpoints set by that command. This
263 applies to breakpoints set by `rbreak', and also applies when a
264 single `break' command creates multiple breakpoints (e.g.,
265 breakpoints on overloaded c++ functions).
267 * The `rbreak' command now accepts a filename specification as part of
268 its argument, limiting the functions selected by the regex to those
269 in the specified file.
271 * Support for remote debugging Windows and SymbianOS shared libraries
272 from Unix hosts has been improved. Non Windows GDB builds now can
273 understand target reported file names that follow MS-DOS based file
274 system semantics, such as file names that include drive letters and
275 use the backslash character as directory separator. This makes it
276 possible to transparently use the "set sysroot" and "set
277 solib-search-path" on Unix hosts to point as host copies of the
278 target's shared libraries. See the new command "set
279 target-file-system-kind" described below, and the "Commands to
280 specify files" section in the user manual for more information.
284 eval template, expressions...
285 Convert the values of one or more expressions under the control
286 of the string template to a command line, and call it.
288 set target-file-system-kind unix|dos-based|auto
289 show target-file-system-kind
290 Set or show the assumed file system kind for target reported file
293 save breakpoints <filename>
294 Save all current breakpoint definitions to a file suitable for use
295 in a later debugging session. To read the saved breakpoint
296 definitions, use the `source' command.
298 `save tracepoints' is a new alias for `save-tracepoints'. The latter
301 info static-tracepoint-markers
302 Display information about static tracepoint markers in the target.
304 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
305 Define a static tracepoint by probing a marker at the given
306 function, line, address, or marker ID.
310 Enable and disable observer mode.
312 set may-write-registers on|off
313 set may-write-memory on|off
314 set may-insert-breakpoints on|off
315 set may-insert-tracepoints on|off
316 set may-insert-fast-tracepoints on|off
317 set may-interrupt on|off
318 Set individual permissions for GDB effects on the target. Note that
319 some of these settings can have undesirable or surprising
320 consequences, particularly when changed in the middle of a session.
321 For instance, disabling the writing of memory can prevent
322 breakpoints from being inserted, cause single-stepping to fail, or
323 even crash your program, if you disable after breakpoints have been
324 inserted. However, GDB should not crash.
326 set record memory-query on|off
327 show record memory-query
328 Control whether to stop the inferior if memory changes caused
329 by an instruction cannot be recorded.
334 The disassemble command now supports "start,+length" form of two arguments.
338 ** GDB now provides a new directory location, called the python directory,
339 where Python scripts written for GDB can be installed. The location
340 of that directory is <data-directory>/python, where <data-directory>
341 is the GDB data directory. For more details, see section `Scripting
342 GDB using Python' in the manual.
344 ** The GDB Python API now has access to breakpoints, symbols, symbol
345 tables, program spaces, inferiors, threads and frame's code blocks.
346 Additionally, GDB Parameters can now be created from the API, and
347 manipulated via set/show in the CLI.
349 ** New functions gdb.target_charset, gdb.target_wide_charset,
350 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
352 ** New exception gdb.GdbError.
354 ** Pretty-printers are now also looked up in the current program space.
356 ** Pretty-printers can now be individually enabled and disabled.
358 ** GDB now looks for names of Python scripts to auto-load in a
359 special section named `.debug_gdb_scripts', in addition to looking
360 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
362 * Tracepoint actions were unified with breakpoint commands. In particular,
363 there are no longer differences in "info break" output for breakpoints and
364 tracepoints and the "commands" command can be used for both tracepoints and
369 ARM Symbian arm*-*-symbianelf*
371 * D language support.
372 GDB now supports debugging programs written in the D programming
375 * GDB now supports the extended ptrace interface for PowerPC which is
376 available since Linux kernel version 2.6.34. This automatically enables
377 any hardware breakpoints and additional hardware watchpoints available in
378 the processor. The old ptrace interface exposes just one hardware
379 watchpoint and no hardware breakpoints.
381 * GDB is now able to use the Data Value Compare (DVC) register available on
382 embedded PowerPC processors to implement in hardware simple watchpoint
383 conditions of the form:
385 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
387 This works in native GDB running on Linux kernels with the extended ptrace
388 interface mentioned above.
390 *** Changes in GDB 7.1
396 GDB now supports importing of namespaces in C++. This enables the
397 user to inspect variables from imported namespaces. Support for
398 namepace aliasing has also been added. So, if a namespace is
399 aliased in the current scope (e.g. namepace C=A; ) the user can
400 print variables using the alias (e.g. (gdb) print C::x).
404 All known bugs relating to the printing of virtual base class were
405 fixed. It is now possible to call overloaded static methods using a
410 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
411 and reinterpret_cast<> are now handled by the C++ expression parser.
415 Xilinx MicroBlaze microblaze-*-*
420 Xilinx MicroBlaze microblaze
423 * Multi-program debugging.
425 GDB now has support for multi-program (a.k.a. multi-executable or
426 multi-exec) debugging. This allows for debugging multiple inferiors
427 simultaneously each running a different program under the same GDB
428 session. See "Debugging Multiple Inferiors and Programs" in the
429 manual for more information. This implied some user visible changes
430 in the multi-inferior support. For example, "info inferiors" now
431 lists inferiors that are not running yet or that have exited
432 already. See also "New commands" and "New options" below.
434 * New tracing features
436 GDB's tracepoint facility now includes several new features:
438 ** Trace state variables
440 GDB tracepoints now include support for trace state variables, which
441 are variables managed by the target agent during a tracing
442 experiment. They are useful for tracepoints that trigger each
443 other, so for instance one tracepoint can count hits in a variable,
444 and then a second tracepoint has a condition that is true when the
445 count reaches a particular value. Trace state variables share the
446 $-syntax of GDB convenience variables, and can appear in both
447 tracepoint actions and condition expressions. Use the "tvariable"
448 command to create, and "info tvariables" to view; see "Trace State
449 Variables" in the manual for more detail.
453 GDB now includes an option for defining fast tracepoints, which
454 targets may implement more efficiently, such as by installing a jump
455 into the target agent rather than a trap instruction. The resulting
456 speedup can be by two orders of magnitude or more, although the
457 tradeoff is that some program locations on some target architectures
458 might not allow fast tracepoint installation, for instance if the
459 instruction to be replaced is shorter than the jump. To request a
460 fast tracepoint, use the "ftrace" command, with syntax identical to
461 the regular trace command.
463 ** Disconnected tracing
465 It is now possible to detach GDB from the target while it is running
466 a trace experiment, then reconnect later to see how the experiment
467 is going. In addition, a new variable disconnected-tracing lets you
468 tell the target agent whether to continue running a trace if the
469 connection is lost unexpectedly.
473 GDB now has the ability to save the trace buffer into a file, and
474 then use that file as a target, similarly to you can do with
475 corefiles. You can select trace frames, print data that was
476 collected in them, and use tstatus to display the state of the
477 tracing run at the moment that it was saved. To create a trace
478 file, use "tsave <filename>", and to use it, do "target tfile
481 ** Circular trace buffer
483 You can ask the target agent to handle the trace buffer as a
484 circular buffer, discarding the oldest trace frames to make room for
485 newer ones, by setting circular-trace-buffer to on. This feature may
486 not be available for all target agents.
491 The disassemble command, when invoked with two arguments, now requires
492 the arguments to be comma-separated.
495 The info variables command now displays variable definitions. Files
496 which only declare a variable are not shown.
499 The source command is now capable of sourcing Python scripts.
500 This feature is dependent on the debugger being build with Python
503 Related to this enhancement is also the introduction of a new command
504 "set script-extension" (see below).
506 * New commands (for set/show, see "New options" below)
508 record save [<FILENAME>]
509 Save a file (in core file format) containing the process record
510 execution log for replay debugging at a later time.
512 record restore <FILENAME>
513 Restore the process record execution log that was saved at an
514 earlier time, for replay debugging.
516 add-inferior [-copies <N>] [-exec <FILENAME>]
519 clone-inferior [-copies <N>] [ID]
520 Make a new inferior ready to execute the same program another
526 maint info program-spaces
527 List the program spaces loaded into GDB.
529 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
530 show remote interrupt-sequence
531 Allow the user to select one of ^C, a BREAK signal or BREAK-g
532 as the sequence to the remote target in order to interrupt the execution.
533 Ctrl-C is a default. Some system prefers BREAK which is high level of
534 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
535 Magic SysRq g. It is BREAK signal and character 'g'.
537 set remote interrupt-on-connect [on | off]
538 show remote interrupt-on-connect
539 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
540 remote target when gdb connects to it. This is needed when you debug
543 set remotebreak [on | off]
545 Deprecated. Use "set/show remote interrupt-sequence" instead.
547 tvariable $NAME [ = EXP ]
548 Create or modify a trace state variable.
551 List trace state variables and their values.
553 delete tvariable $NAME ...
554 Delete one or more trace state variables.
557 Evaluate the given expressions without collecting anything into the
558 trace buffer. (Valid in tracepoint actions only.)
560 ftrace FN / FILE:LINE / *ADDR
561 Define a fast tracepoint at the given function, line, or address.
563 * New expression syntax
565 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
566 GDB now parses 0b101010 identically with 42.
570 set follow-exec-mode new|same
571 show follow-exec-mode
572 Control whether GDB reuses the same inferior across an exec call or
573 creates a new one. This is useful to be able to restart the old
574 executable after the inferior having done an exec call.
576 set default-collect EXPR, ...
578 Define a list of expressions to be collected at each tracepoint.
579 This is a useful way to ensure essential items are not overlooked,
580 such as registers or a critical global variable.
582 set disconnected-tracing
583 show disconnected-tracing
584 If set to 1, the target is instructed to continue tracing if it
585 loses its connection to GDB. If 0, the target is to stop tracing
588 set circular-trace-buffer
589 show circular-trace-buffer
590 If set to on, the target is instructed to use a circular trace buffer
591 and discard the oldest trace frames instead of stopping the trace due
592 to a full trace buffer. If set to off, the trace stops when the buffer
593 fills up. Some targets may not support this.
595 set script-extension off|soft|strict
596 show script-extension
597 If set to "off", the debugger does not perform any script language
598 recognition, and all sourced files are assumed to be GDB scripts.
599 If set to "soft" (the default), files are sourced according to
600 filename extension, falling back to GDB scripts if the first
602 If set to "strict", files are sourced according to filename extension.
604 set ada trust-PAD-over-XVS on|off
605 show ada trust-PAD-over-XVS
606 If off, activate a workaround against a bug in the debugging information
607 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
608 the GCC sources for more information about the GNAT encoding and
609 PAD types in particular). It is always safe to set this option to
610 off, but this introduces a slight performance penalty. The default
613 * Python API Improvements
615 ** GDB provides the new class gdb.LazyString. This is useful in
616 some pretty-printing cases. The new method gdb.Value.lazy_string
617 provides a simple way to create objects of this type.
619 ** The fields returned by gdb.Type.fields now have an
620 `is_base_class' attribute.
622 ** The new method gdb.Type.range returns the range of an array type.
624 ** The new method gdb.parse_and_eval can be used to parse and
625 evaluate an expression.
630 Define a trace state variable.
633 Get the current value of a trace state variable.
636 Set desired tracing behavior upon disconnection.
639 Set the trace buffer to be linear or circular.
642 Get data about the tracepoints currently in use.
646 Process record now works correctly with hardware watchpoints.
648 Multiple bug fixes have been made to the mips-irix port, making it
649 much more reliable. In particular:
650 - Debugging threaded applications is now possible again. Previously,
651 GDB would hang while starting the program, or while waiting for
652 the program to stop at a breakpoint.
653 - Attaching to a running process no longer hangs.
654 - An error occurring while loading a core file has been fixed.
655 - Changing the value of the PC register now works again. This fixes
656 problems observed when using the "jump" command, or when calling
657 a function from GDB, or even when assigning a new value to $pc.
658 - With the "finish" and "return" commands, the return value for functions
659 returning a small array is now correctly printed.
660 - It is now possible to break on shared library code which gets executed
661 during a shared library init phase (code executed while executing
662 their .init section). Previously, the breakpoint would have no effect.
663 - GDB is now able to backtrace through the signal handler for
664 non-threaded programs.
666 PIE (Position Independent Executable) programs debugging is now supported.
667 This includes debugging execution of PIC (Position Independent Code) shared
668 libraries although for that, it should be possible to run such libraries as an
671 *** Changes in GDB 7.0
673 * GDB now has an interface for JIT compilation. Applications that
674 dynamically generate code can create symbol files in memory and register
675 them with GDB. For users, the feature should work transparently, and
676 for JIT developers, the interface is documented in the GDB manual in the
677 "JIT Compilation Interface" chapter.
679 * Tracepoints may now be conditional. The syntax is as for
680 breakpoints; either an "if" clause appended to the "trace" command,
681 or the "condition" command is available. GDB sends the condition to
682 the target for evaluation using the same bytecode format as is used
683 for tracepoint actions.
685 * The disassemble command now supports: an optional /r modifier, print the
686 raw instructions in hex as well as in symbolic form, and an optional /m
687 modifier to print mixed source+assembly.
689 * Process record and replay
691 In a architecture environment that supports ``process record and
692 replay'', ``process record and replay'' target can record a log of
693 the process execution, and replay it with both forward and reverse
696 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
697 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
698 set execution-direction {forward|reverse}, for targets that support
701 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
702 feature is available with a native GDB running on kernel version
705 * GDB now has support for multi-byte and wide character sets on the
706 target. Strings whose character type is wchar_t, char16_t, or
707 char32_t are now correctly printed. GDB supports wide- and unicode-
708 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
709 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
710 `printf'. This feature requires iconv to work properly; if your
711 system does not have a working iconv, GDB can use GNU libiconv. See
712 the installation instructions for more information.
714 * GDB now supports automatic retrieval of shared library files from
715 remote targets. To use this feature, specify a system root that begins
716 with the `remote:' prefix, either via the `set sysroot' command or via
717 the `--with-sysroot' configure-time option.
719 * "info sharedlibrary" now takes an optional regex of libraries to show,
720 and it now reports if a shared library has no debugging information.
722 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
723 now complete on file names.
725 * When completing in expressions, gdb will attempt to limit
726 completions to allowable structure or union fields, where appropriate.
727 For instance, consider:
729 # struct example { int f1; double f2; };
730 # struct example variable;
733 If the user types TAB at the end of this command line, the available
734 completions will be "f1" and "f2".
736 * Inlined functions are now supported. They show up in backtraces, and
737 the "step", "next", and "finish" commands handle them automatically.
739 * GDB now supports the token-splicing (##) and stringification (#)
740 operators when expanding macros. It also supports variable-arity
743 * GDB now supports inspecting extra signal information, exported by
744 the new $_siginfo convenience variable. The feature is currently
745 implemented on linux ARM, i386 and amd64.
747 * GDB can now display the VFP floating point registers and NEON vector
748 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
749 can provide these registers (requires Linux 2.6.30 or later). Remote
750 and simulator targets may also provide them.
755 Search memory for a sequence of bytes.
758 Turn off `+'/`-' protocol acknowledgments to permit more efficient
759 operation over reliable transport links. Use of this packet is
760 controlled by the `set remote noack-packet' command.
763 Kill the process with the specified process ID. Use this in preference
764 to `k' when multiprocess protocol extensions are supported.
767 Obtains additional operating system information
771 Read or write additional signal information.
773 * Removed remote protocol undocumented extension
775 An undocumented extension to the remote protocol's `S' stop reply
776 packet that permited the stub to pass a process id was removed.
777 Remote servers should use the `T' stop reply packet instead.
779 * GDB now supports multiple function calling conventions according to the
780 DWARF-2 DW_AT_calling_convention function attribute.
782 * The SH target utilizes the aforementioned change to distinguish between gcc
783 and Renesas calling convention. It also adds the new CLI commands
784 `set/show sh calling-convention'.
786 * GDB can now read compressed debug sections, as produced by GNU gold
787 with the --compress-debug-sections=zlib flag.
789 * 64-bit core files are now supported on AIX.
791 * Thread switching is now supported on Tru64.
793 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
794 which will be allocated using malloc later in program execution.
796 * The qXfer:libraries:read remote procotol packet now allows passing a
797 list of section offsets.
799 * On GNU/Linux, GDB can now attach to stopped processes. Several race
800 conditions handling signals delivered during attach or thread creation
801 have also been fixed.
803 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
804 From the user's standpoint, all unqualified instances of True and False
805 are treated as the standard definitions, regardless of context.
807 * GDB now parses C++ symbol and type names more flexibly. For
810 template<typename T> class C { };
813 GDB will now correctly handle all of:
815 ptype C<char const *>
817 ptype C<const char *>
820 * New features in the GDB remote stub, gdbserver
822 - The "--wrapper" command-line argument tells gdbserver to use a
823 wrapper program to launch programs for debugging.
825 - On PowerPC and S/390 targets, it is now possible to use a single
826 gdbserver executable to debug both 32-bit and 64-bit programs.
827 (This requires gdbserver itself to be built as a 64-bit executable.)
829 - gdbserver uses the new noack protocol mode for TCP connections to
830 reduce communications latency, if also supported and enabled in GDB.
832 - Support for the sparc64-linux-gnu target is now included in
835 - The amd64-linux build of gdbserver now supports debugging both
836 32-bit and 64-bit programs.
838 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
839 now support hardware watchpoints, and will use them automatically
844 GDB now has support for scripting using Python. Whether this is
845 available is determined at configure time.
847 New GDB commands can now be written in Python.
849 * Ada tasking support
851 Ada tasks can now be inspected in GDB. The following commands have
855 Print the list of Ada tasks.
857 Print detailed information about task number N.
859 Print the task number of the current task.
861 Switch the context of debugging to task number N.
863 * Support for user-defined prefixed commands. The "define" command can
864 add new commands to existing prefixes, e.g. "target".
866 * Multi-inferior, multi-process debugging.
868 GDB now has generalized support for multi-inferior debugging. See
869 "Debugging Multiple Inferiors" in the manual for more information.
870 Although availability still depends on target support, the command
871 set is more uniform now. The GNU/Linux specific multi-forks support
872 has been migrated to this new framework. This implied some user
873 visible changes; see "New commands" and also "Removed commands"
876 * Target descriptions can now describe the target OS ABI. See the
877 "Target Description Format" section in the user manual for more
880 * Target descriptions can now describe "compatible" architectures
881 to indicate that the target can execute applications for a different
882 architecture in addition to those for the main target architecture.
883 See the "Target Description Format" section in the user manual for
886 * Multi-architecture debugging.
888 GDB now includes general supports for debugging applications on
889 hybrid systems that use more than one single processor architecture
890 at the same time. Each such hybrid architecture still requires
891 specific support to be added. The only hybrid architecture supported
892 in this version of GDB is the Cell Broadband Engine.
894 * GDB now supports integrated debugging of Cell/B.E. applications that
895 use both the PPU and SPU architectures. To enable support for hybrid
896 Cell/B.E. debugging, you need to configure GDB to support both the
897 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
898 --enable-targets configure option.
900 * Non-stop mode debugging.
902 For some targets, GDB now supports an optional mode of operation in
903 which you can examine stopped threads while other threads continue
904 to execute freely. This is referred to as non-stop mode, with the
905 old mode referred to as all-stop mode. See the "Non-Stop Mode"
906 section in the user manual for more information.
908 To be able to support remote non-stop debugging, a remote stub needs
909 to implement the non-stop mode remote protocol extensions, as
910 described in the "Remote Non-Stop" section of the user manual. The
911 GDB remote stub, gdbserver, has been adjusted to support these
912 extensions on linux targets.
914 * New commands (for set/show, see "New options" below)
916 catch syscall [NAME(S) | NUMBER(S)]
917 Catch system calls. Arguments, which should be names of system
918 calls or their numbers, mean catch only those syscalls. Without
919 arguments, every syscall will be caught. When the inferior issues
920 any of the specified syscalls, GDB will stop and announce the system
921 call, both when it is called and when its call returns. This
922 feature is currently available with a native GDB running on the
923 Linux Kernel, under the following architectures: x86, x86_64,
924 PowerPC and PowerPC64.
926 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
928 Search memory for a sequence of bytes.
930 maint set python print-stack
931 maint show python print-stack
932 Show a stack trace when an error is encountered in a Python script.
935 Invoke CODE by passing it to the Python interpreter.
940 These allow macros to be defined, undefined, and listed
944 Show operating system information about processes.
947 List the inferiors currently under GDB's control.
950 Switch focus to inferior number NUM.
953 Detach from inferior number NUM.
956 Kill inferior number NUM.
961 show spu stop-on-load
962 Control whether to stop for new SPE threads during Cell/B.E. debugging.
964 set spu auto-flush-cache
965 show spu auto-flush-cache
966 Control whether to automatically flush the software-managed cache
967 during Cell/B.E. debugging.
969 set sh calling-convention
970 show sh calling-convention
971 Control the calling convention used when calling SH target functions.
975 Control display of timestamps with GDB debugging output.
977 set disassemble-next-line
978 show disassemble-next-line
979 Control display of disassembled source lines or instructions when
982 set remote noack-packet
983 show remote noack-packet
984 Set/show the use of remote protocol QStartNoAckMode packet. See above
985 under "New remote packets."
987 set remote query-attached-packet
988 show remote query-attached-packet
989 Control use of remote protocol `qAttached' (query-attached) packet.
991 set remote read-siginfo-object
992 show remote read-siginfo-object
993 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
996 set remote write-siginfo-object
997 show remote write-siginfo-object
998 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1001 set remote reverse-continue
1002 show remote reverse-continue
1003 Control use of remote protocol 'bc' (reverse-continue) packet.
1005 set remote reverse-step
1006 show remote reverse-step
1007 Control use of remote protocol 'bs' (reverse-step) packet.
1009 set displaced-stepping
1010 show displaced-stepping
1011 Control displaced stepping mode. Displaced stepping is a way to
1012 single-step over breakpoints without removing them from the debuggee.
1013 Also known as "out-of-line single-stepping".
1016 show debug displaced
1017 Control display of debugging info for displaced stepping.
1019 maint set internal-error
1020 maint show internal-error
1021 Control what GDB does when an internal error is detected.
1023 maint set internal-warning
1024 maint show internal-warning
1025 Control what GDB does when an internal warning is detected.
1030 Use a wrapper program to launch programs for debugging.
1032 set multiple-symbols (all|ask|cancel)
1033 show multiple-symbols
1034 The value of this variable can be changed to adjust the debugger behavior
1035 when an expression or a breakpoint location contains an ambiguous symbol
1036 name (an overloaded function name, for instance).
1038 set breakpoint always-inserted
1039 show breakpoint always-inserted
1040 Keep breakpoints always inserted in the target, as opposed to inserting
1041 them when resuming the target, and removing them when the target stops.
1042 This option can improve debugger performance on slow remote targets.
1044 set arm fallback-mode (arm|thumb|auto)
1045 show arm fallback-mode
1046 set arm force-mode (arm|thumb|auto)
1048 These commands control how ARM GDB determines whether instructions
1049 are ARM or Thumb. The default for both settings is auto, which uses
1050 the current CPSR value for instructions without symbols; previous
1051 versions of GDB behaved as if "set arm fallback-mode arm".
1053 set disable-randomization
1054 show disable-randomization
1055 Standalone programs run with the virtual address space randomization enabled
1056 by default on some platforms. This option keeps the addresses stable across
1057 multiple debugging sessions.
1061 Control whether other threads are stopped or not when some thread hits
1066 Requests that asynchronous execution is enabled in the target, if available.
1067 In this case, it's possible to resume target in the background, and interact
1068 with GDB while the target is running. "show target-async" displays the
1069 current state of asynchronous execution of the target.
1071 set target-wide-charset
1072 show target-wide-charset
1073 The target-wide-charset is the name of the character set that GDB
1074 uses when printing characters whose type is wchar_t.
1076 set tcp auto-retry (on|off)
1078 set tcp connect-timeout
1079 show tcp connect-timeout
1080 These commands allow GDB to retry failed TCP connections to a remote stub
1081 with a specified timeout period; this is useful if the stub is launched
1082 in parallel with GDB but may not be ready to accept connections immediately.
1084 set libthread-db-search-path
1085 show libthread-db-search-path
1086 Control list of directories which GDB will search for appropriate
1089 set schedule-multiple (on|off)
1090 show schedule-multiple
1091 Allow GDB to resume all threads of all processes or only threads of
1092 the current process.
1096 Use more aggressive caching for accesses to the stack. This improves
1097 performance of remote debugging (particularly backtraces) without
1098 affecting correctness.
1100 set interactive-mode (on|off|auto)
1101 show interactive-mode
1102 Control whether GDB runs in interactive mode (on) or not (off).
1103 When in interactive mode, GDB waits for the user to answer all
1104 queries. Otherwise, GDB does not wait and assumes the default
1105 answer. When set to auto (the default), GDB determines which
1106 mode to use based on the stdin settings.
1111 For program forks, this is replaced by the new more generic `info
1112 inferiors' command. To list checkpoints, you can still use the
1113 `info checkpoints' command, which was an alias for the `info forks'
1117 Replaced by the new `inferior' command. To switch between
1118 checkpoints, you can still use the `restart' command, which was an
1119 alias for the `fork' command.
1122 This is removed, since some targets don't have a notion of
1123 processes. To switch between processes, you can still use the
1124 `inferior' command using GDB's own inferior number.
1127 For program forks, this is replaced by the new more generic `kill
1128 inferior' command. To delete a checkpoint, you can still use the
1129 `delete checkpoint' command, which was an alias for the `delete
1133 For program forks, this is replaced by the new more generic `detach
1134 inferior' command. To detach a checkpoint, you can still use the
1135 `detach checkpoint' command, which was an alias for the `detach
1138 * New native configurations
1140 x86/x86_64 Darwin i[34567]86-*-darwin*
1142 x86_64 MinGW x86_64-*-mingw*
1146 Lattice Mico32 lm32-*
1147 x86 DICOS i[34567]86-*-dicos*
1148 x86_64 DICOS x86_64-*-dicos*
1151 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1152 (mingw32ce) debugging.
1158 These commands were actually not implemented on any target.
1160 *** Changes in GDB 6.8
1162 * New native configurations
1164 NetBSD/hppa hppa*-*netbsd*
1165 Xtensa GNU/Linux xtensa*-*-linux*
1169 NetBSD/hppa hppa*-*-netbsd*
1170 Xtensa GNU/Lunux xtensa*-*-linux*
1172 * Change in command line behavior -- corefiles vs. process ids.
1174 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1175 attaching to process NUMBER fails, GDB no longer attempts to open a
1176 core file named NUMBER. Attaching to a program using the -c option
1177 is no longer supported. Instead, use the '-p' or '--pid' options.
1179 * GDB can now be built as a native debugger for debugging Windows x86
1180 (mingw32) Portable Executable (PE) programs.
1182 * Pending breakpoints no longer change their number when their address
1185 * GDB now supports breakpoints with multiple locations,
1186 including breakpoints on C++ constructors, inside C++ templates,
1187 and in inlined functions.
1189 * GDB's ability to debug optimized code has been improved. GDB more
1190 accurately identifies function bodies and lexical blocks that occupy
1191 more than one contiguous range of addresses.
1193 * Target descriptions can now describe registers for PowerPC.
1195 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1196 registers on PowerPC targets.
1198 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1199 targets even when the libthread_db library is not available.
1201 * The GDB remote stub, gdbserver, now supports the new file transfer
1202 commands (remote put, remote get, and remote delete).
1204 * The GDB remote stub, gdbserver, now supports run and attach in
1205 extended-remote mode.
1207 * hppa*64*-*-hpux11* target broken
1208 The debugger is unable to start a program and fails with the following
1209 error: "Error trying to get information about dynamic linker".
1210 The gdb-6.7 release is also affected.
1212 * GDB now supports the --enable-targets= configure option to allow
1213 building a single GDB executable that supports multiple remote
1214 target architectures.
1216 * GDB now supports debugging C and C++ programs which use the
1217 Decimal Floating Point extension. In addition, the PowerPC target
1218 now has a set of pseudo-registers to inspect decimal float values
1219 stored in two consecutive float registers.
1221 * The -break-insert MI command can optionally create pending
1224 * Improved support for debugging Ada
1225 Many improvements to the Ada language support have been made. These
1227 - Better support for Ada2005 interface types
1228 - Improved handling of arrays and slices in general
1229 - Better support for Taft-amendment types
1230 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1232 - Improved command completion in Ada
1235 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1240 set print frame-arguments (all|scalars|none)
1241 show print frame-arguments
1242 The value of this variable can be changed to control which argument
1243 values should be printed by the debugger when displaying a frame.
1248 Transfer files to and from a remote target, and delete remote files.
1255 Transfer files to and from a remote target, and delete remote files.
1257 * New remote packets
1264 Open, close, read, write, and delete files on the remote system.
1267 Attach to an existing process on the remote system, in extended-remote
1271 Run a new process on the remote system, in extended-remote mode.
1273 *** Changes in GDB 6.7
1275 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1276 bfd, libiberty and opcodes, as revealed by static analysis donated by
1277 Coverity, Inc. (http://scan.coverity.com).
1279 * When looking up multiply-defined global symbols, GDB will now prefer the
1280 symbol definition in the current shared library if it was built using the
1281 -Bsymbolic linker option.
1283 * When the Text User Interface (TUI) is not configured, GDB will now
1284 recognize the -tui command-line option and print a message that the TUI
1287 * The GDB remote stub, gdbserver, now has lower overhead for high
1288 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1290 * GDB for MIPS targets now autodetects whether a remote target provides
1291 32-bit or 64-bit register values.
1293 * Support for C++ member pointers has been improved.
1295 * GDB now understands XML target descriptions, which specify the
1296 target's overall architecture. GDB can read a description from
1297 a local file or over the remote serial protocol.
1299 * Vectors of single-byte data use a new integer type which is not
1300 automatically displayed as character or string data.
1302 * The /s format now works with the print command. It displays
1303 arrays of single-byte integers and pointers to single-byte integers
1306 * Target descriptions can now describe target-specific registers,
1307 for architectures which have implemented the support (currently
1308 only ARM, M68K, and MIPS).
1310 * GDB and the GDB remote stub, gdbserver, now support the XScale
1313 * The GDB remote stub, gdbserver, has been updated to support
1314 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1315 has been rewritten to use the standard GDB remote protocol.
1317 * GDB can now step into C++ functions which are called through thunks.
1319 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1321 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1322 layout. It also supports a TextSeg= and DataSeg= response when only
1323 segment base addresses (rather than offsets) are available.
1325 * The /i format now outputs any trailing branch delay slot instructions
1326 immediately following the last instruction within the count specified.
1328 * The GDB remote protocol "T" stop reply packet now supports a
1329 "library" response. Combined with the new "qXfer:libraries:read"
1330 packet, this response allows GDB to debug shared libraries on targets
1331 where the operating system manages the list of loaded libraries (e.g.
1332 Windows and SymbianOS).
1334 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1335 (DLLs) on Windows and Windows CE targets.
1337 * GDB now supports a faster verification that a .debug file matches its binary
1338 according to its build-id signature, if the signature is present.
1344 Enable or disable hardware flow control (RTS/CTS) on the serial port
1345 when debugging using remote targets.
1347 set mem inaccessible-by-default
1348 show mem inaccessible-by-default
1349 If the target supplies a memory map, for instance via the remote
1350 protocol's "qXfer:memory-map:read" packet, setting this variable
1351 prevents GDB from accessing memory outside the memory map. This
1352 is useful for targets with memory mapped registers or which react
1353 badly to accesses of unmapped address space.
1355 set breakpoint auto-hw
1356 show breakpoint auto-hw
1357 If the target supplies a memory map, for instance via the remote
1358 protocol's "qXfer:memory-map:read" packet, setting this variable
1359 lets GDB use hardware breakpoints automatically for memory regions
1360 where it can not use software breakpoints. This covers both the
1361 "break" command and internal breakpoints used for other commands
1362 including "next" and "finish".
1365 catch exception unhandled
1366 Stop the program execution when Ada exceptions are raised.
1369 Stop the program execution when an Ada assertion failed.
1373 Set an alternate system root for target files. This is a more
1374 general version of "set solib-absolute-prefix", which is now
1375 an alias to "set sysroot".
1378 Provide extended SPU facility status information. This set of
1379 commands is available only when debugging the Cell/B.E. SPU
1382 * New native configurations
1384 OpenBSD/sh sh*-*openbsd*
1387 unset tdesc filename
1389 Use the specified local file as an XML target description, and do
1390 not query the target for its built-in description.
1394 OpenBSD/sh sh*-*-openbsd*
1395 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1396 Toshiba Media Processor mep-elf
1398 * New remote packets
1401 Ignore the specified signals; pass them directly to the debugged program
1402 without stopping other threads or reporting them to GDB.
1404 qXfer:features:read:
1405 Read an XML target description from the target, which describes its
1410 Read or write contents of an spufs file on the target system. These
1411 packets are available only on the Cell/B.E. SPU architecture.
1413 qXfer:libraries:read:
1414 Report the loaded shared libraries. Combined with new "T" packet
1415 response, this packet allows GDB to debug shared libraries on
1416 targets where the operating system manages the list of loaded
1417 libraries (e.g. Windows and SymbianOS).
1421 Support for these obsolete configurations has been removed.
1429 i[34567]86-*-lynxos*
1430 i[34567]86-*-netware*
1431 i[34567]86-*-sco3.2v5*
1432 i[34567]86-*-sco3.2v4*
1434 i[34567]86-*-sysv4.2*
1437 i[34567]86-*-unixware2*
1438 i[34567]86-*-unixware*
1447 * Other removed features
1454 Various m68k-only ROM monitors.
1461 Various Renesas ROM monitors and debugging interfaces for SH and
1466 Support for a Macraigor serial interface to on-chip debugging.
1467 GDB does not directly support the newer parallel or USB
1472 A debug information format. The predecessor to DWARF 2 and
1473 DWARF 3, which are still supported.
1475 Support for the HP aCC compiler on HP-UX/PA-RISC
1477 SOM-encapsulated symbolic debugging information, automatic
1478 invocation of pxdb, and the aCC custom C++ ABI. This does not
1479 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1480 with aCC can still be debugged on an assembly level.
1482 MIPS ".pdr" sections
1484 A MIPS-specific format used to describe stack frame layout
1485 in debugging information.
1489 GDB could work with an older version of Guile to debug
1490 the interpreter and Scheme programs running in it.
1492 set mips stack-arg-size
1493 set mips saved-gpreg-size
1495 Use "set mips abi" to control parameter passing for MIPS.
1497 *** Changes in GDB 6.6
1502 Cell Broadband Engine SPU spu-elf
1504 * GDB can now be configured as a cross-debugger targeting native Windows
1505 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1506 running on a Windows system over TCP/IP to debug Windows programs.
1508 * The GDB remote stub, gdbserver, has been updated to support Windows and
1509 Cygwin debugging. Both single-threaded and multi-threaded programs are
1512 * The "set trust-readonly-sections" command works again. This command was
1513 broken in GDB 6.3, 6.4, and 6.5.
1515 * The "load" command now supports writing to flash memory, if the remote
1516 stub provides the required support.
1518 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1519 longer requires symbolic debug information (e.g. DWARF-2).
1524 unset substitute-path
1525 show substitute-path
1526 Manage a list of substitution rules that GDB uses to rewrite the name
1527 of the directories where the sources are located. This can be useful
1528 for instance when the sources were moved to a different location
1529 between compilation and debugging.
1533 Print each CLI command as it is executed. Each command is prefixed with
1534 a number of `+' symbols representing the nesting depth.
1535 The source command now has a `-v' option to enable the same feature.
1539 The ARM Demon monitor support (RDP protocol, "target rdp").
1541 Kernel Object Display, an embedded debugging feature which only worked with
1542 an obsolete version of Cisco IOS.
1544 The 'set download-write-size' and 'show download-write-size' commands.
1546 * New remote packets
1549 Tell a stub about GDB client features, and request remote target features.
1550 The first feature implemented is PacketSize, which allows the target to
1551 specify the size of packets it can handle - to minimize the number of
1552 packets required and improve performance when connected to a remote
1556 Fetch an OS auxilliary vector from the remote stub. This packet is a
1557 more efficient replacement for qPart:auxv:read.
1559 qXfer:memory-map:read:
1560 Fetch a memory map from the remote stub, including information about
1561 RAM, ROM, and flash memory devices.
1566 Erase and program a flash memory device.
1568 * Removed remote packets
1571 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1572 used it, and only gdbserver implemented it.
1574 *** Changes in GDB 6.5
1578 Renesas M32C/M16C m32c-elf
1580 Morpho Technologies ms1 ms1-elf
1584 init-if-undefined Initialize a convenience variable, but
1585 only if it doesn't already have a value.
1587 The following commands are presently only implemented for native GNU/Linux:
1589 checkpoint Save a snapshot of the program state.
1591 restart <n> Return the program state to a
1592 previously saved state.
1594 info checkpoints List currently saved checkpoints.
1596 delete-checkpoint <n> Delete a previously saved checkpoint.
1598 set|show detach-on-fork Tell gdb whether to detach from a newly
1599 forked process, or to keep debugging it.
1601 info forks List forks of the user program that
1602 are available to be debugged.
1604 fork <n> Switch to debugging one of several
1605 forks of the user program that are
1606 available to be debugged.
1608 delete-fork <n> Delete a fork from the list of forks
1609 that are available to be debugged (and
1610 kill the forked process).
1612 detach-fork <n> Delete a fork from the list of forks
1613 that are available to be debugged (and
1614 allow the process to continue).
1618 Morpho Technologies ms2 ms1-elf
1620 * Improved Windows host support
1622 GDB now builds as a cross debugger hosted on i686-mingw32, including
1623 native console support, and remote communications using either
1624 network sockets or serial ports.
1626 * Improved Modula-2 language support
1628 GDB can now print most types in the Modula-2 syntax. This includes:
1629 basic types, set types, record types, enumerated types, range types,
1630 pointer types and ARRAY types. Procedure var parameters are correctly
1631 printed and hexadecimal addresses and character constants are also
1632 written in the Modula-2 syntax. Best results can be obtained by using
1633 GNU Modula-2 together with the -gdwarf-2 command line option.
1637 The ARM rdi-share module.
1639 The Netware NLM debug server.
1641 *** Changes in GDB 6.4
1643 * New native configurations
1645 OpenBSD/arm arm*-*-openbsd*
1646 OpenBSD/mips64 mips64-*-openbsd*
1650 Morpho Technologies ms1 ms1-elf
1652 * New command line options
1654 --batch-silent As for --batch, but totally silent.
1655 --return-child-result The debugger will exist with the same value
1656 the child (debugged) program exited with.
1657 --eval-command COMMAND, -ex COMMAND
1658 Execute a single GDB CLI command. This may be
1659 specified multiple times and in conjunction
1660 with the --command (-x) option.
1662 * Deprecated commands removed
1664 The following commands, that were deprecated in 2000, have been
1668 set|show arm disassembly-flavor set|show arm disassembler
1669 othernames set arm disassembler
1670 set|show remotedebug set|show debug remote
1671 set|show archdebug set|show debug arch
1672 set|show eventdebug set|show debug event
1675 * New BSD user-level threads support
1677 It is now possible to debug programs using the user-level threads
1678 library on OpenBSD and FreeBSD. Currently supported (target)
1681 FreeBSD/amd64 x86_64-*-freebsd*
1682 FreeBSD/i386 i386-*-freebsd*
1683 OpenBSD/i386 i386-*-openbsd*
1685 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1686 are not yet supported.
1688 * New support for Matsushita MN10300 w/sim added
1689 (Work in progress). mn10300-elf.
1691 * REMOVED configurations and files
1693 VxWorks and the XDR protocol *-*-vxworks
1694 Motorola MCORE mcore-*-*
1695 National Semiconductor NS32000 ns32k-*-*
1697 * New "set print array-indexes" command
1699 After turning this setting "on", GDB prints the index of each element
1700 when displaying arrays. The default is "off" to preserve the previous
1703 * VAX floating point support
1705 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1707 * User-defined command support
1709 In addition to using $arg0..$arg9 for argument passing, it is now possible
1710 to use $argc to determine now many arguments have been passed. See the
1711 section on user-defined commands in the user manual for more information.
1713 *** Changes in GDB 6.3:
1715 * New command line option
1717 GDB now accepts -l followed by a number to set the timeout for remote
1720 * GDB works with GCC -feliminate-dwarf2-dups
1722 GDB now supports a more compact representation of DWARF-2 debug
1723 information using DW_FORM_ref_addr references. These are produced
1724 by GCC with the option -feliminate-dwarf2-dups and also by some
1725 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1726 to use -feliminate-dwarf2-dups.
1728 * Internationalization
1730 When supported by the host system, GDB will be built with
1731 internationalization (libintl). The task of marking up the sources is
1732 continued, we're looking forward to our first translation.
1736 Initial support for debugging programs compiled with the GNAT
1737 implementation of the Ada programming language has been integrated
1738 into GDB. In this release, support is limited to expression evaluation.
1740 * New native configurations
1742 GNU/Linux/m32r m32r-*-linux-gnu
1746 GDB's remote protocol now includes support for the 'p' packet. This
1747 packet is used to fetch individual registers from a remote inferior.
1749 * END-OF-LIFE registers[] compatibility module
1751 GDB's internal register infrastructure has been completely rewritten.
1752 The new infrastructure making possible the implementation of key new
1753 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1756 GDB 6.3 will be the last release to include the the registers[]
1757 compatibility module that allowed out-of-date configurations to
1758 continue to work. This change directly impacts the following
1768 powerpc bdm protocol
1770 Unless there is activity to revive these configurations, they will be
1771 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1773 * OBSOLETE configurations and files
1775 Configurations that have been declared obsolete in this release have
1776 been commented out. Unless there is activity to revive these
1777 configurations, the next release of GDB will have their sources
1778 permanently REMOVED.
1787 *** Changes in GDB 6.2.1:
1789 * MIPS `break main; run' gave an heuristic-fence-post warning
1791 When attempting to run even a simple program, a warning about
1792 heuristic-fence-post being hit would be reported. This problem has
1795 * MIPS IRIX 'long double' crashed GDB
1797 When examining a long double variable, GDB would get a segmentation
1798 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1799 IRIX long double values).
1803 A bug in the VAX stack code was causing problems with the "next"
1804 command. This problem has been fixed.
1806 *** Changes in GDB 6.2:
1808 * Fix for ``many threads''
1810 On GNU/Linux systems that use the NPTL threads library, a program
1811 rapidly creating and deleting threads would confuse GDB leading to the
1814 ptrace: No such process.
1815 thread_db_get_info: cannot get thread info: generic error
1817 This problem has been fixed.
1819 * "-async" and "-noasync" options removed.
1821 Support for the broken "-noasync" option has been removed (it caused
1824 * New ``start'' command.
1826 This command runs the program until the begining of the main procedure.
1828 * New BSD Kernel Data Access Library (libkvm) interface
1830 Using ``target kvm'' it is now possible to debug kernel core dumps and
1831 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1832 platforms. Currently supported (native-only) configurations are:
1834 FreeBSD/amd64 x86_64-*-freebsd*
1835 FreeBSD/i386 i?86-*-freebsd*
1836 NetBSD/i386 i?86-*-netbsd*
1837 NetBSD/m68k m68*-*-netbsd*
1838 NetBSD/sparc sparc-*-netbsd*
1839 OpenBSD/amd64 x86_64-*-openbsd*
1840 OpenBSD/i386 i?86-*-openbsd*
1841 OpenBSD/m68k m68*-openbsd*
1842 OpenBSD/sparc sparc-*-openbsd*
1844 * Signal trampoline code overhauled
1846 Many generic problems with GDB's signal handling code have been fixed.
1847 These include: backtraces through non-contiguous stacks; recognition
1848 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1849 call; backtrace through a signal trampoline; step into and out of
1850 signal handlers; and single-stepping in the signal trampoline.
1852 Please note that kernel bugs are a limiting factor here. These
1853 features have been shown to work on an s390 GNU/Linux system that
1854 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1856 * Cygwin support for DWARF 2 added.
1858 * New native configurations
1860 GNU/Linux/hppa hppa*-*-linux*
1861 OpenBSD/hppa hppa*-*-openbsd*
1862 OpenBSD/m68k m68*-*-openbsd*
1863 OpenBSD/m88k m88*-*-openbsd*
1864 OpenBSD/powerpc powerpc-*-openbsd*
1865 NetBSD/vax vax-*-netbsd*
1866 OpenBSD/vax vax-*-openbsd*
1868 * END-OF-LIFE frame compatibility module
1870 GDB's internal frame infrastructure has been completely rewritten.
1871 The new infrastructure making it possible to support key new features
1872 including DWARF 2 Call Frame Information. To aid in the task of
1873 migrating old configurations to this new infrastructure, a
1874 compatibility module, that allowed old configurations to continue to
1875 work, was also included.
1877 GDB 6.2 will be the last release to include this frame compatibility
1878 module. This change directly impacts the following configurations:
1888 Unless there is activity to revive these configurations, they will be
1889 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1891 * REMOVED configurations and files
1893 Sun 3, running SunOS 3 m68*-*-sunos3*
1894 Sun 3, running SunOS 4 m68*-*-sunos4*
1895 Sun 2, running SunOS 3 m68000-*-sunos3*
1896 Sun 2, running SunOS 4 m68000-*-sunos4*
1897 Motorola 680x0 running LynxOS m68*-*-lynxos*
1898 AT&T 3b1/Unix pc m68*-att-*
1899 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1900 decstation mips-dec-* mips-little-*
1901 riscos mips-*-riscos* mips-*-sysv*
1902 sonymips mips-sony-*
1903 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1905 *** Changes in GDB 6.1.1:
1907 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1909 The TUI (Text-mode User Interface) is now built as part of a default
1910 GDB configuration. It is enabled by either selecting the TUI with the
1911 command line option "-i=tui" or by running the separate "gdbtui"
1912 program. For more information on the TUI, see the manual "Debugging
1915 * Pending breakpoint support (also included in GDB 6.1)
1917 Support has been added to allow you to specify breakpoints in shared
1918 libraries that have not yet been loaded. If a breakpoint location
1919 cannot be found, and the "breakpoint pending" option is set to auto,
1920 GDB queries you if you wish to make the breakpoint pending on a future
1921 shared-library load. If and when GDB resolves the breakpoint symbol,
1922 the pending breakpoint is removed as one or more regular breakpoints
1925 Pending breakpoints are very useful for GCJ Java debugging.
1927 * Fixed ISO-C build problems
1929 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1930 non ISO-C code that stopped them being built using a more strict ISO-C
1931 compiler (e.g., IBM's C compiler).
1933 * Fixed build problem on IRIX 5
1935 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1936 wasn't able to compile compile on an IRIX 5 system.
1938 * Added execute permission to gdb/gdbserver/configure
1940 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1941 permission. This bug would cause configure to fail on a number of
1942 systems (Solaris, IRIX). Ref: server/519.
1944 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1946 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1947 has been updated to use constant array sizes.
1949 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1951 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1952 its generated DWARF Call Frame Info. This encoding was causing GDB to
1953 panic, that panic has been fixed. Ref: gdb/1628.
1955 * Fixed a problem when examining parameters in shared library code.
1957 When examining parameters in optimized shared library code generated
1958 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1959 not available''. GDB now correctly displays the variable's value.
1961 *** Changes in GDB 6.1:
1963 * Removed --with-mmalloc
1965 Support for the mmalloc memory manager has been removed, as it
1966 conflicted with the internal gdb byte cache.
1968 * Changes in AMD64 configurations
1970 The AMD64 target now includes the %cs and %ss registers. As a result
1971 the AMD64 remote protocol has changed; this affects the floating-point
1972 and SSE registers. If you rely on those registers for your debugging,
1973 you should upgrade gdbserver on the remote side.
1975 * Revised SPARC target
1977 The SPARC target has been completely revised, incorporating the
1978 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1979 support for LynxOS and SunOS 4 has been dropped. Calling functions
1980 from within GDB on operating systems with a non-executable stack
1981 (Solaris, OpenBSD) now works.
1985 GDB has a new C++ demangler which does a better job on the mangled
1986 names generated by current versions of g++. It also runs faster, so
1987 with this and other changes gdb should now start faster on large C++
1990 * DWARF 2 Location Expressions
1992 GDB support for location expressions has been extended to support function
1993 arguments and frame bases. Older versions of GDB could crash when they
1996 * C++ nested types and namespaces
1998 GDB's support for nested types and namespaces in C++ has been
1999 improved, especially if you use the DWARF 2 debugging format. (This
2000 is the default for recent versions of GCC on most platforms.)
2001 Specifically, if you have a class "Inner" defined within a class or
2002 namespace "Outer", then GDB realizes that the class's name is
2003 "Outer::Inner", not simply "Inner". This should greatly reduce the
2004 frequency of complaints about not finding RTTI symbols. In addition,
2005 if you are stopped at inside of a function defined within a namespace,
2006 GDB modifies its name lookup accordingly.
2008 * New native configurations
2010 NetBSD/amd64 x86_64-*-netbsd*
2011 OpenBSD/amd64 x86_64-*-openbsd*
2012 OpenBSD/alpha alpha*-*-openbsd*
2013 OpenBSD/sparc sparc-*-openbsd*
2014 OpenBSD/sparc64 sparc64-*-openbsd*
2016 * New debugging protocols
2018 M32R with SDI protocol m32r-*-elf*
2020 * "set prompt-escape-char" command deleted.
2022 The command "set prompt-escape-char" has been deleted. This command,
2023 and its very obscure effet on GDB's prompt, was never documented,
2024 tested, nor mentioned in the NEWS file.
2026 * OBSOLETE configurations and files
2028 Configurations that have been declared obsolete in this release have
2029 been commented out. Unless there is activity to revive these
2030 configurations, the next release of GDB will have their sources
2031 permanently REMOVED.
2033 Sun 3, running SunOS 3 m68*-*-sunos3*
2034 Sun 3, running SunOS 4 m68*-*-sunos4*
2035 Sun 2, running SunOS 3 m68000-*-sunos3*
2036 Sun 2, running SunOS 4 m68000-*-sunos4*
2037 Motorola 680x0 running LynxOS m68*-*-lynxos*
2038 AT&T 3b1/Unix pc m68*-att-*
2039 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2040 decstation mips-dec-* mips-little-*
2041 riscos mips-*-riscos* mips-*-sysv*
2042 sonymips mips-sony-*
2043 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2045 * REMOVED configurations and files
2047 SGI Irix-4.x mips-sgi-irix4 or iris4
2048 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2049 Z8000 simulator z8k-zilog-none or z8ksim
2050 Matsushita MN10200 w/simulator mn10200-*-*
2051 H8/500 simulator h8500-hitachi-hms or h8500hms
2052 HP/PA running BSD hppa*-*-bsd*
2053 HP/PA running OSF/1 hppa*-*-osf*
2054 HP/PA Pro target hppa*-*-pro*
2055 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2056 386BSD i[3456]86-*-bsd*
2057 Sequent family i[3456]86-sequent-sysv4*
2058 i[3456]86-sequent-sysv*
2059 i[3456]86-sequent-bsd*
2060 SPARC running LynxOS sparc-*-lynxos*
2061 SPARC running SunOS 4 sparc-*-sunos4*
2062 Tsqware Sparclet sparclet-*-*
2063 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2065 *** Changes in GDB 6.0:
2069 Support for debugging the Objective-C programming language has been
2070 integrated into GDB.
2072 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2074 DWARF 2's Call Frame Information makes available compiler generated
2075 information that more exactly describes the program's run-time stack.
2076 By using this information, GDB is able to provide more robust stack
2079 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2080 have been updated to use a new backtrace mechanism which includes
2081 DWARF 2 CFI support.
2085 GDB's remote protocol has been extended to include support for hosted
2086 file I/O (where the remote target uses GDB's file system). See GDB's
2087 remote protocol documentation for details.
2089 * All targets using the new architecture framework.
2091 All of GDB's targets have been updated to use the new internal
2092 architecture framework. The way is now open for future GDB releases
2093 to include cross-architecture native debugging support (i386 on amd64,
2096 * GNU/Linux's Thread Local Storage (TLS)
2098 GDB now includes support for for the GNU/Linux implementation of
2099 per-thread variables.
2101 * GNU/Linux's Native POSIX Thread Library (NPTL)
2103 GDB's thread code has been updated to work with either the new
2104 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2106 * Separate debug info.
2108 GDB, in conjunction with BINUTILS, now supports a mechanism for
2109 automatically loading debug information from a separate file. Instead
2110 of shipping full debug and non-debug versions of system libraries,
2111 system integrators can now instead ship just the stripped libraries
2112 and optional debug files.
2114 * DWARF 2 Location Expressions
2116 DWARF 2 Location Expressions allow the compiler to more completely
2117 describe the location of variables (even in optimized code) to the
2120 GDB now includes preliminary support for location expressions (support
2121 for DW_OP_piece is still missing).
2125 A number of long standing bugs that caused GDB to die while starting a
2126 Java application have been fixed. GDB's Java support is now
2127 considered "useable".
2129 * GNU/Linux support for fork, vfork, and exec.
2131 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2132 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2135 * GDB supports logging output to a file
2137 There are two new commands, "set logging" and "show logging", which can be
2138 used to capture GDB's output to a file.
2140 * The meaning of "detach" has changed for gdbserver
2142 The "detach" command will now resume the application, as documented. To
2143 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2146 * d10v, m68hc11 `regs' command deprecated
2148 The `info registers' command has been updated so that it displays the
2149 registers using a format identical to the old `regs' command.
2153 A new command, "maint set profile on/off", has been added. This command can
2154 be used to enable or disable profiling while running GDB, to profile a
2155 session or a set of commands. In addition there is a new configure switch,
2156 "--enable-profiling", which will cause GDB to be compiled with profiling
2157 data, for more informative profiling results.
2159 * Default MI syntax changed to "mi2".
2161 The default MI (machine interface) syntax, enabled by the command line
2162 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2163 "mi1", can be enabled by specifying the option "-i=mi1".
2165 Support for the original "mi0" syntax (included in GDB 5.0) has been
2168 Fix for gdb/192: removed extraneous space when displaying frame level.
2169 Fix for gdb/672: update changelist is now output in mi list format.
2170 Fix for gdb/702: a -var-assign that updates the value now shows up
2171 in a subsequent -var-update.
2173 * New native configurations.
2175 FreeBSD/amd64 x86_64-*-freebsd*
2177 * Multi-arched targets.
2179 HP/PA HPUX11 hppa*-*-hpux*
2180 Renesas M32R/D w/simulator m32r-*-elf*
2182 * OBSOLETE configurations and files
2184 Configurations that have been declared obsolete in this release have
2185 been commented out. Unless there is activity to revive these
2186 configurations, the next release of GDB will have their sources
2187 permanently REMOVED.
2189 Z8000 simulator z8k-zilog-none or z8ksim
2190 Matsushita MN10200 w/simulator mn10200-*-*
2191 H8/500 simulator h8500-hitachi-hms or h8500hms
2192 HP/PA running BSD hppa*-*-bsd*
2193 HP/PA running OSF/1 hppa*-*-osf*
2194 HP/PA Pro target hppa*-*-pro*
2195 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2196 Sequent family i[3456]86-sequent-sysv4*
2197 i[3456]86-sequent-sysv*
2198 i[3456]86-sequent-bsd*
2199 Tsqware Sparclet sparclet-*-*
2200 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2202 * REMOVED configurations and files
2205 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2206 IBM AIX PS/2 i[3456]86-*-aix
2207 i386 running Mach 3.0 i[3456]86-*-mach3*
2208 i386 running Mach i[3456]86-*-mach*
2209 i386 running OSF/1 i[3456]86-*osf1mk*
2210 HP/Apollo 68k Family m68*-apollo*-sysv*,
2212 m68*-hp-bsd*, m68*-hp-hpux*
2213 Argonaut Risc Chip (ARC) arc-*-*
2214 Mitsubishi D30V d30v-*-*
2215 Fujitsu FR30 fr30-*-elf*
2216 OS/9000 i[34]86-*-os9k
2217 I960 with MON960 i960-*-coff
2219 * MIPS $fp behavior changed
2221 The convenience variable $fp, for the MIPS, now consistently returns
2222 the address of the current frame's base. Previously, depending on the
2223 context, $fp could refer to either $sp or the current frame's base
2224 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2225 The GNU Source-Level Debugger''.
2227 *** Changes in GDB 5.3:
2229 * GNU/Linux shared library multi-threaded performance improved.
2231 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2232 `/proc', in preference to `ptrace' for memory reads. This may result
2233 in an improvement in the start-up time of multi-threaded, shared
2234 library applications when run under GDB. One GDB user writes: ``loads
2235 shared libs like mad''.
2237 * ``gdbserver'' now supports multi-threaded applications on some targets
2239 Support for debugging multi-threaded applications which use
2240 the GNU/Linux LinuxThreads package has been added for
2241 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2242 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2244 * GDB now supports C/C++ preprocessor macros.
2246 GDB now expands preprocessor macro invocations in C/C++ expressions,
2247 and provides various commands for showing macro definitions and how
2250 The new command `macro expand EXPRESSION' expands any macro
2251 invocations in expression, and shows the result.
2253 The new command `show macro MACRO-NAME' shows the definition of the
2254 macro named MACRO-NAME, and where it was defined.
2256 Most compilers don't include information about macros in the debugging
2257 information by default. In GCC 3.1, for example, you need to compile
2258 your program with the options `-gdwarf-2 -g3'. If the macro
2259 information is present in the executable, GDB will read it.
2261 * Multi-arched targets.
2263 DEC Alpha (partial) alpha*-*-*
2264 DEC VAX (partial) vax-*-*
2266 National Semiconductor NS32000 (partial) ns32k-*-*
2267 Motorola 68000 (partial) m68k-*-*
2268 Motorola MCORE mcore-*-*
2272 Fujitsu FRV architecture added by Red Hat frv*-*-*
2275 * New native configurations
2277 Alpha NetBSD alpha*-*-netbsd*
2278 SH NetBSD sh*-*-netbsdelf*
2279 MIPS NetBSD mips*-*-netbsd*
2280 UltraSPARC NetBSD sparc64-*-netbsd*
2282 * OBSOLETE configurations and files
2284 Configurations that have been declared obsolete in this release have
2285 been commented out. Unless there is activity to revive these
2286 configurations, the next release of GDB will have their sources
2287 permanently REMOVED.
2289 Mitsubishi D30V d30v-*-*
2290 OS/9000 i[34]86-*-os9k
2291 IBM AIX PS/2 i[3456]86-*-aix
2292 Fujitsu FR30 fr30-*-elf*
2293 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2294 Argonaut Risc Chip (ARC) arc-*-*
2295 i386 running Mach 3.0 i[3456]86-*-mach3*
2296 i386 running Mach i[3456]86-*-mach*
2297 i386 running OSF/1 i[3456]86-*osf1mk*
2298 HP/Apollo 68k Family m68*-apollo*-sysv*,
2300 m68*-hp-bsd*, m68*-hp-hpux*
2301 I960 with MON960 i960-*-coff
2303 * OBSOLETE languages
2305 CHILL, a Pascal like language used by telecommunications companies.
2307 * REMOVED configurations and files
2309 AMD 29k family via UDI a29k-amd-udi, udi29k
2310 A29K VxWorks a29k-*-vxworks
2311 AMD 29000 embedded, using EBMON a29k-none-none
2312 AMD 29000 embedded with COFF a29k-none-coff
2313 AMD 29000 embedded with a.out a29k-none-aout
2315 testsuite/gdb.hp/gdb.threads-hp/ directory
2317 * New command "set max-user-call-depth <nnn>"
2319 This command allows the user to limit the call depth of user-defined
2320 commands. The default is 1024.
2322 * Changes in FreeBSD/i386 native debugging.
2324 Support for the "generate-core-file" has been added.
2326 * New commands "dump", "append", and "restore".
2328 These commands allow data to be copied from target memory
2329 to a bfd-format or binary file (dump and append), and back
2330 from a file into memory (restore).
2332 * Improved "next/step" support on multi-processor Alpha Tru64.
2334 The previous single-step mechanism could cause unpredictable problems,
2335 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2336 of a software single-step mechanism prevents this.
2338 *** Changes in GDB 5.2.1:
2346 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2347 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2348 Fix, by Joel Brobecker imported from mainline.
2350 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2351 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2352 Fix, by Fred Fish, imported from mainline.
2354 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2355 Surprisingly enough, it works now.
2356 By Michal Ludvig, imported from mainline.
2358 i386 hardware watchpoint support:
2359 avoid misses on second run for some targets.
2360 By Pierre Muller, imported from mainline.
2362 *** Changes in GDB 5.2:
2364 * New command "set trust-readonly-sections on[off]".
2366 This command is a hint that tells gdb that read-only sections
2367 really are read-only (ie. that their contents will not change).
2368 In this mode, gdb will go to the object file rather than the
2369 target to read memory from read-only sections (such as ".text").
2370 This can be a significant performance improvement on some
2371 (notably embedded) targets.
2373 * New command "generate-core-file" (or "gcore").
2375 This new gdb command allows the user to drop a core file of the child
2376 process state at any time. So far it's been implemented only for
2377 GNU/Linux and Solaris, but should be relatively easily ported to other
2378 hosts. Argument is core file name (defaults to core.<pid>).
2380 * New command line option
2382 GDB now accepts --pid or -p followed by a process id.
2384 * Change in command line behavior -- corefiles vs. process ids.
2386 There is a subtle behavior in the way in which GDB handles
2387 command line arguments. The first non-flag argument is always
2388 a program to debug, but the second non-flag argument may either
2389 be a corefile or a process id. Previously, GDB would attempt to
2390 open the second argument as a corefile, and if that failed, would
2391 issue a superfluous error message and then attempt to attach it as
2392 a process. Now, if the second argument begins with a non-digit,
2393 it will be treated as a corefile. If it begins with a digit,
2394 GDB will attempt to attach it as a process, and if no such process
2395 is found, will then attempt to open it as a corefile.
2397 * Changes in ARM configurations.
2399 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2400 configuration is fully multi-arch.
2402 * New native configurations
2404 ARM NetBSD arm*-*-netbsd*
2405 x86 OpenBSD i[3456]86-*-openbsd*
2406 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2407 Sparc64 running FreeBSD sparc64-*-freebsd*
2411 Sanyo XStormy16 xstormy16-elf
2413 * OBSOLETE configurations and files
2415 Configurations that have been declared obsolete in this release have
2416 been commented out. Unless there is activity to revive these
2417 configurations, the next release of GDB will have their sources
2418 permanently REMOVED.
2420 AMD 29k family via UDI a29k-amd-udi, udi29k
2421 A29K VxWorks a29k-*-vxworks
2422 AMD 29000 embedded, using EBMON a29k-none-none
2423 AMD 29000 embedded with COFF a29k-none-coff
2424 AMD 29000 embedded with a.out a29k-none-aout
2426 testsuite/gdb.hp/gdb.threads-hp/ directory
2428 * REMOVED configurations and files
2430 TI TMS320C80 tic80-*-*
2432 PowerPC Solaris powerpcle-*-solaris*
2433 PowerPC Windows NT powerpcle-*-cygwin32
2434 PowerPC Netware powerpc-*-netware*
2435 Harris/CXUX m88k m88*-harris-cxux*
2436 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2437 ns32k-utek-sysv* ns32k-utek-*
2438 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2439 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2440 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2441 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2442 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2444 * Changes to command line processing
2446 The new `--args' feature can be used to specify command-line arguments
2447 for the inferior from gdb's command line.
2449 * Changes to key bindings
2451 There is a new `operate-and-get-next' function bound to `C-o'.
2453 *** Changes in GDB 5.1.1
2455 Fix compile problem on DJGPP.
2457 Fix a problem with floating-point registers on the i386 being
2460 Fix to stop GDB crashing on .debug_str debug info.
2462 Numerous documentation fixes.
2464 Numerous testsuite fixes.
2466 *** Changes in GDB 5.1:
2468 * New native configurations
2470 Alpha FreeBSD alpha*-*-freebsd*
2471 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2472 MIPS GNU/Linux mips*-*-linux*
2473 MIPS SGI Irix 6.x mips*-sgi-irix6*
2474 ia64 AIX ia64-*-aix*
2475 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2479 Motorola 68HC11 and 68HC12 m68hc11-elf
2481 UltraSparc running GNU/Linux sparc64-*-linux*
2483 * OBSOLETE configurations and files
2485 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2486 Harris/CXUX m88k m88*-harris-cxux*
2487 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2488 ns32k-utek-sysv* ns32k-utek-*
2489 TI TMS320C80 tic80-*-*
2491 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2492 PowerPC Solaris powerpcle-*-solaris*
2493 PowerPC Windows NT powerpcle-*-cygwin32
2494 PowerPC Netware powerpc-*-netware*
2495 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2496 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2497 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2498 Apple Macintosh (MPW) host N/A
2500 stuff.c (Program to stuff files into a specially prepared space in kdb)
2501 kdb-start.c (Main loop for the standalone kernel debugger)
2503 Configurations that have been declared obsolete in this release have
2504 been commented out. Unless there is activity to revive these
2505 configurations, the next release of GDB will have their sources
2506 permanently REMOVED.
2508 * REMOVED configurations and files
2510 Altos 3068 m68*-altos-*
2511 Convex c1-*-*, c2-*-*
2513 ARM RISCix arm-*-* (as host)
2517 * GDB has been converted to ISO C.
2519 GDB's source code has been converted to ISO C. In particular, the
2520 sources are fully protoized, and rely on standard headers being
2525 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2527 * The MI enabled by default.
2529 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2530 revised and enabled by default. Packages which use GDB as a debugging
2531 engine behind a UI or another front end are encouraged to switch to
2532 using the GDB/MI interface, instead of the old annotations interface
2533 which is now deprecated.
2535 * Support for debugging Pascal programs.
2537 GDB now includes support for debugging Pascal programs. The following
2538 main features are supported:
2540 - Pascal-specific data types such as sets;
2542 - automatic recognition of Pascal sources based on file-name
2545 - Pascal-style display of data types, variables, and functions;
2547 - a Pascal expression parser.
2549 However, some important features are not yet supported.
2551 - Pascal string operations are not supported at all;
2553 - there are some problems with boolean types;
2555 - Pascal type hexadecimal constants are not supported
2556 because they conflict with the internal variables format;
2558 - support for Pascal objects and classes is not full yet;
2560 - unlike Pascal, GDB is case-sensitive for symbol names.
2562 * Changes in completion.
2564 Commands such as `shell', `run' and `set args', which pass arguments
2565 to inferior programs, now complete on file names, similar to what
2566 users expect at the shell prompt.
2568 Commands which accept locations, such as `disassemble', `print',
2569 `breakpoint', `until', etc. now complete on filenames as well as
2570 program symbols. Thus, if you type "break foob TAB", and the source
2571 files linked into the programs include `foobar.c', that file name will
2572 be one of the candidates for completion. However, file names are not
2573 considered for completion after you typed a colon that delimits a file
2574 name from a name of a function in that file, as in "break foo.c:bar".
2576 `set demangle-style' completes on available demangling styles.
2578 * New platform-independent commands:
2580 It is now possible to define a post-hook for a command as well as a
2581 hook that runs before the command. For more details, see the
2582 documentation of `hookpost' in the GDB manual.
2584 * Changes in GNU/Linux native debugging.
2586 Support for debugging multi-threaded programs has been completely
2587 revised for all platforms except m68k and sparc. You can now debug as
2588 many threads as your system allows you to have.
2590 Attach/detach is supported for multi-threaded programs.
2592 Support for SSE registers was added for x86. This doesn't work for
2593 multi-threaded programs though.
2595 * Changes in MIPS configurations.
2597 Multi-arch support is enabled for all MIPS configurations.
2599 GDB can now be built as native debugger on SGI Irix 6.x systems for
2600 debugging n32 executables. (Debugging 64-bit executables is not yet
2603 * Unified support for hardware watchpoints in all x86 configurations.
2605 Most (if not all) native x86 configurations support hardware-assisted
2606 breakpoints and watchpoints in a unified manner. This support
2607 implements debug register sharing between watchpoints, which allows to
2608 put a virtually infinite number of watchpoints on the same address,
2609 and also supports watching regions up to 16 bytes with several debug
2612 The new maintenance command `maintenance show-debug-regs' toggles
2613 debugging print-outs in functions that insert, remove, and test
2614 watchpoints and hardware breakpoints.
2616 * Changes in the DJGPP native configuration.
2618 New command ``info dos sysinfo'' displays assorted information about
2619 the CPU, OS, memory, and DPMI server.
2621 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2622 display information about segment descriptors stored in GDT, LDT, and
2625 New commands ``info dos pde'' and ``info dos pte'' display entries
2626 from Page Directory and Page Tables (for now works with CWSDPMI only).
2627 New command ``info dos address-pte'' displays the Page Table entry for
2628 a given linear address.
2630 GDB can now pass command lines longer than 126 characters to the
2631 program being debugged (requires an update to the libdbg.a library
2632 which is part of the DJGPP development kit).
2634 DWARF2 debug info is now supported.
2636 It is now possible to `step' and `next' through calls to `longjmp'.
2638 * Changes in documentation.
2640 All GDB documentation was converted to GFDL, the GNU Free
2641 Documentation License.
2643 Tracepoints-related commands are now fully documented in the GDB
2646 TUI, the Text-mode User Interface, is now documented in the manual.
2648 Tracepoints-related commands are now fully documented in the GDB
2651 The "GDB Internals" manual now has an index. It also includes
2652 documentation of `ui_out' functions, GDB coding standards, x86
2653 hardware watchpoints, and memory region attributes.
2655 * GDB's version number moved to ``version.in''
2657 The Makefile variable VERSION has been replaced by the file
2658 ``version.in''. People creating GDB distributions should update the
2659 contents of this file.
2663 GUD support is now a standard part of the EMACS distribution.
2665 *** Changes in GDB 5.0:
2667 * Improved support for debugging FP programs on x86 targets
2669 Unified and much-improved support for debugging floating-point
2670 programs on all x86 targets. In particular, ``info float'' now
2671 displays the FP registers in the same format on all x86 targets, with
2672 greater level of detail.
2674 * Improvements and bugfixes in hardware-assisted watchpoints
2676 It is now possible to watch array elements, struct members, and
2677 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2678 on x86 targets no longer erroneously trigger when the address is
2681 * Improvements in the native DJGPP version of GDB
2683 The distribution now includes all the scripts and auxiliary files
2684 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2685 machines ``out of the box''.
2687 The DJGPP version can now debug programs that use signals. It is
2688 possible to catch signals that happened in the debuggee, deliver
2689 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2690 would kill the program being debugged.) Programs that hook hardware
2691 interrupts (keyboard, timer, etc.) can also be debugged.
2693 It is now possible to debug DJGPP programs that redirect their
2694 standard handles or switch them to raw (as opposed to cooked) mode, or
2695 even close them. The command ``run < foo > bar'' works as expected,
2696 and ``info terminal'' reports useful information about the debuggee's
2697 terminal, including raw/cooked mode, redirection, etc.
2699 The DJGPP version now uses termios functions for console I/O, which
2700 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2703 DOS-style file names with drive letters are now fully supported by
2706 It is now possible to debug DJGPP programs that switch their working
2707 directory. It is also possible to rerun the debuggee any number of
2708 times without restarting GDB; thus, you can use the same setup,
2709 breakpoints, etc. for many debugging sessions.
2711 * New native configurations
2713 ARM GNU/Linux arm*-*-linux*
2714 PowerPC GNU/Linux powerpc-*-linux*
2718 Motorola MCore mcore-*-*
2719 x86 VxWorks i[3456]86-*-vxworks*
2720 PowerPC VxWorks powerpc-*-vxworks*
2721 TI TMS320C80 tic80-*-*
2723 * OBSOLETE configurations
2725 Altos 3068 m68*-altos-*
2726 Convex c1-*-*, c2-*-*
2728 ARM RISCix arm-*-* (as host)
2731 Configurations that have been declared obsolete will be commented out,
2732 but the code will be left in place. If there is no activity to revive
2733 these configurations before the next release of GDB, the sources will
2734 be permanently REMOVED.
2736 * Gould support removed
2738 Support for the Gould PowerNode and NP1 has been removed.
2740 * New features for SVR4
2742 On SVR4 native platforms (such as Solaris), if you attach to a process
2743 without first loading a symbol file, GDB will now attempt to locate and
2744 load symbols from the running process's executable file.
2746 * Many C++ enhancements
2748 C++ support has been greatly improved. Overload resolution now works properly
2749 in almost all cases. RTTI support is on the way.
2751 * Remote targets can connect to a sub-program
2753 A popen(3) style serial-device has been added. This device starts a
2754 sub-process (such as a stand-alone simulator) and then communicates
2755 with that. The sub-program to run is specified using the syntax
2756 ``|<program> <args>'' vis:
2758 (gdb) set remotedebug 1
2759 (gdb) target extended-remote |mn10300-elf-sim program-args
2761 * MIPS 64 remote protocol
2763 A long standing bug in the mips64 remote protocol where by GDB
2764 expected certain 32 bit registers (ex SR) to be transfered as 32
2765 instead of 64 bits has been fixed.
2767 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2768 added to provide backward compatibility with older versions of GDB.
2770 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2772 The command ``set remotebinarydownload'' command has been replaced by
2773 ``set remote X-packet''. Other commands in ``set remote'' family
2774 include ``set remote P-packet''.
2776 * Breakpoint commands accept ranges.
2778 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2779 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2780 ``tracepoint passcount'' also accepts a range of tracepoints.
2782 * ``apropos'' command added.
2784 The ``apropos'' command searches through command names and
2785 documentation strings, printing out matches, making it much easier to
2786 try to find a command that does what you are looking for.
2790 A new machine oriented interface (MI) has been added to GDB. This
2791 interface is designed for debug environments running GDB as a separate
2792 process. This is part of the long term libGDB project. See the
2793 "GDB/MI" chapter of the GDB manual for further information. It can be
2794 enabled by configuring with:
2796 .../configure --enable-gdbmi
2798 *** Changes in GDB-4.18:
2800 * New native configurations
2802 HP-UX 10.20 hppa*-*-hpux10.20
2803 HP-UX 11.x hppa*-*-hpux11.0*
2804 M68K GNU/Linux m68*-*-linux*
2808 Fujitsu FR30 fr30-*-elf*
2809 Intel StrongARM strongarm-*-*
2810 Mitsubishi D30V d30v-*-*
2812 * OBSOLETE configurations
2814 Gould PowerNode, NP1 np1-*-*, pn-*-*
2816 Configurations that have been declared obsolete will be commented out,
2817 but the code will be left in place. If there is no activity to revive
2818 these configurations before the next release of GDB, the sources will
2819 be permanently REMOVED.
2823 As a compatibility experiment, GDB's source files buildsym.h and
2824 buildsym.c have been converted to pure standard C, no longer
2825 containing any K&R compatibility code. We believe that all systems in
2826 use today either come with a standard C compiler, or have a GCC port
2827 available. If this is not true, please report the affected
2828 configuration to bug-gdb@gnu.org immediately. See the README file for
2829 information about getting a standard C compiler if you don't have one
2834 GDB now uses readline 2.2.
2836 * set extension-language
2838 You can now control the mapping between filename extensions and source
2839 languages by using the `set extension-language' command. For instance,
2840 you can ask GDB to treat .c files as C++ by saying
2841 set extension-language .c c++
2842 The command `info extensions' lists all of the recognized extensions
2843 and their associated languages.
2845 * Setting processor type for PowerPC and RS/6000
2847 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2848 you can use the `set processor' command to specify what variant of the
2849 PowerPC family you are debugging. The command
2853 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2854 following PowerPC and RS6000 variants:
2856 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2857 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2859 403GC IBM PowerPC 403GC
2860 505 Motorola PowerPC 505
2861 860 Motorola PowerPC 860 or 850
2862 601 Motorola PowerPC 601
2863 602 Motorola PowerPC 602
2864 603 Motorola/IBM PowerPC 603 or 603e
2865 604 Motorola PowerPC 604 or 604e
2866 750 Motorola/IBM PowerPC 750 or 750
2868 At the moment, this command just tells GDB what to name the
2869 special-purpose processor registers. Since almost all the affected
2870 registers are inaccessible to user-level programs, this command is
2871 only useful for remote debugging in its present form.
2875 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2876 more extensive support for HP-UX. Added features include shared
2877 library support, kernel threads and hardware watchpoints for 11.00,
2878 support for HP's ANSI C and C++ compilers, and a compatibility mode
2879 for xdb and dbx commands.
2883 HP's donation includes the new concept of catchpoints, which is a
2884 generalization of the old catch command. On HP-UX, it is now possible
2885 to catch exec, fork, and vfork, as well as library loading.
2887 This means that the existing catch command has changed; its first
2888 argument now specifies the type of catch to be set up. See the
2889 output of "help catch" for a list of catchpoint types.
2891 * Debugging across forks
2893 On HP-UX, you can choose which process to debug when a fork() happens
2898 HP has donated a curses-based terminal user interface (TUI). To get
2899 it, build with --enable-tui. Although this can be enabled for any
2900 configuration, at present it only works for native HP debugging.
2902 * GDB remote protocol additions
2904 A new protocol packet 'X' that writes binary data is now available.
2905 Default behavior is to try 'X', then drop back to 'M' if the stub
2906 fails to respond. The settable variable `remotebinarydownload'
2907 allows explicit control over the use of 'X'.
2909 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2910 full 64-bit address. The command
2912 set remoteaddresssize 32
2914 can be used to revert to the old behaviour. For existing remote stubs
2915 the change should not be noticed, as the additional address information
2918 In order to assist in debugging stubs, you may use the maintenance
2919 command `packet' to send any text string to the stub. For instance,
2921 maint packet heythere
2923 sends the packet "$heythere#<checksum>". Note that it is very easy to
2924 disrupt a debugging session by sending the wrong packet at the wrong
2927 The compare-sections command allows you to compare section data on the
2928 target to what is in the executable file without uploading or
2929 downloading, by comparing CRC checksums.
2931 * Tracing can collect general expressions
2933 You may now collect general expressions at tracepoints. This requires
2934 further additions to the target-side stub; see tracepoint.c and
2935 doc/agentexpr.texi for further details.
2937 * mask-address variable for Mips
2939 For Mips targets, you may control the zeroing of the upper 32 bits of
2940 a 64-bit address by entering `set mask-address on'. This is mainly
2941 of interest to users of embedded R4xxx and R5xxx processors.
2943 * Higher serial baud rates
2945 GDB's serial code now allows you to specify baud rates 57600, 115200,
2946 230400, and 460800 baud. (Note that your host system may not be able
2947 to achieve all of these rates.)
2951 The i960 configuration now includes an initial implementation of a
2952 builtin simulator, contributed by Jim Wilson.
2955 *** Changes in GDB-4.17:
2957 * New native configurations
2959 Alpha GNU/Linux alpha*-*-linux*
2960 Unixware 2.x i[3456]86-unixware2*
2961 Irix 6.x mips*-sgi-irix6*
2962 PowerPC GNU/Linux powerpc-*-linux*
2963 PowerPC Solaris powerpcle-*-solaris*
2964 Sparc GNU/Linux sparc-*-linux*
2965 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2969 Argonaut Risc Chip (ARC) arc-*-*
2970 Hitachi H8/300S h8300*-*-*
2971 Matsushita MN10200 w/simulator mn10200-*-*
2972 Matsushita MN10300 w/simulator mn10300-*-*
2973 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2974 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2975 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2976 Mitsubishi D10V w/simulator d10v-*-*
2977 Mitsubishi M32R/D w/simulator m32r-*-elf*
2978 Tsqware Sparclet sparclet-*-*
2979 NEC V850 w/simulator v850-*-*
2981 * New debugging protocols
2983 ARM with RDI protocol arm*-*-*
2984 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2985 DDB and LSI variants of PMON protocol mips*-*-*
2986 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2987 PowerPC with SDS protocol powerpc{,le}-*-eabi
2988 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2992 All configurations can now understand and use the DWARF 2 debugging
2993 format. The choice is automatic, if the symbol file contains DWARF 2
2998 GDB now includes basic Java language support. This support is
2999 only useful with Java compilers that produce native machine code.
3001 * solib-absolute-prefix and solib-search-path
3003 For SunOS and SVR4 shared libraries, you may now set the prefix for
3004 loading absolute shared library symbol files, and the search path for
3005 locating non-absolute shared library symbol files.
3007 * Live range splitting
3009 GDB can now effectively debug code for which GCC has performed live
3010 range splitting as part of its optimization. See gdb/doc/LRS for
3011 more details on the expected format of the stabs information.
3015 GDB's support for the GNU Hurd, including thread debugging, has been
3016 updated to work with current versions of the Hurd.
3020 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3021 instruction set. ARM GDB automatically detects when Thumb
3022 instructions are in use, and adjusts disassembly and backtracing
3027 GDB's MIPS target configurations now handle the MIP16 16-bit
3032 GDB now includes support for overlays; if an executable has been
3033 linked such that multiple sections are based at the same address, GDB
3034 will decide which section to use for symbolic info. You can choose to
3035 control the decision manually, using overlay commands, or implement
3036 additional target-side support and use "overlay load-target" to bring
3037 in the overlay mapping. Do "help overlay" for more detail.
3041 The command "info symbol <address>" displays information about
3042 the symbol at the specified address.
3046 The standard remote protocol now includes an extension that allows
3047 asynchronous collection and display of trace data. This requires
3048 extensive support in the target-side debugging stub. Tracing mode
3049 includes a new interaction mode in GDB and new commands: see the
3050 file tracepoint.c for more details.
3054 Configurations for embedded MIPS now include a simulator contributed
3055 by Cygnus Solutions. The simulator supports the instruction sets
3056 of most MIPS variants.
3060 Sparc configurations may now include the ERC32 simulator contributed
3061 by the European Space Agency. The simulator is not built into
3062 Sparc targets by default; configure with --enable-sim to include it.
3066 For target configurations that may include multiple variants of a
3067 basic architecture (such as MIPS and SH), you may now set the
3068 architecture explicitly. "set arch" sets, "info arch" lists
3069 the possible architectures.
3071 *** Changes in GDB-4.16:
3073 * New native configurations
3075 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3076 M68K NetBSD m68k-*-netbsd*
3077 PowerPC AIX 4.x powerpc-*-aix*
3078 PowerPC MacOS powerpc-*-macos*
3079 PowerPC Windows NT powerpcle-*-cygwin32
3080 RS/6000 AIX 4.x rs6000-*-aix4*
3084 ARM with RDP protocol arm-*-*
3085 I960 with MON960 i960-*-coff
3086 MIPS VxWorks mips*-*-vxworks*
3087 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3088 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3090 Matra Sparclet sparclet-*-*
3094 The powerpc-eabi configuration now includes the PSIM simulator,
3095 contributed by Andrew Cagney, with assistance from Mike Meissner.
3096 PSIM is a very elaborate model of the PowerPC, including not only
3097 basic instruction set execution, but also details of execution unit
3098 performance and I/O hardware. See sim/ppc/README for more details.
3102 GDB now works with Solaris 2.5.
3104 * Windows 95/NT native
3106 GDB will now work as a native debugger on Windows 95 and Windows NT.
3107 To build it from source, you must use the "gnu-win32" environment,
3108 which uses a DLL to emulate enough of Unix to run the GNU tools.
3109 Further information, binaries, and sources are available at
3110 ftp.cygnus.com, under pub/gnu-win32.
3112 * dont-repeat command
3114 If a user-defined command includes the command `dont-repeat', then the
3115 command will not be repeated if the user just types return. This is
3116 useful if the command is time-consuming to run, so that accidental
3117 extra keystrokes don't run the same command many times.
3119 * Send break instead of ^C
3121 The standard remote protocol now includes an option to send a break
3122 rather than a ^C to the target in order to interrupt it. By default,
3123 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3125 * Remote protocol timeout
3127 The standard remote protocol includes a new variable `remotetimeout'
3128 that allows you to set the number of seconds before GDB gives up trying
3129 to read from the target. The default value is 2.
3131 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3133 By default GDB will automatically keep track of objects as they are
3134 loaded and unloaded by the dynamic linker. By using the command `set
3135 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3136 when shared library events occur, thus allowing you to set breakpoints
3137 in shared libraries which are explicitly loaded by the inferior.
3139 Note this feature does not work on hpux8. On hpux9 you must link
3140 /usr/lib/end.o into your program. This feature should work
3141 automatically on hpux10.
3143 * Irix 5.x hardware watchpoint support
3145 Irix 5 configurations now support the use of hardware watchpoints.
3147 * Mips protocol "SYN garbage limit"
3149 When debugging a Mips target using the `target mips' protocol, you
3150 may set the number of characters that GDB will ignore by setting
3151 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3152 every character. The default value is 1050.
3154 * Recording and replaying remote debug sessions
3156 If you set `remotelogfile' to the name of a file, gdb will write to it
3157 a recording of a remote debug session. This recording may then be
3158 replayed back to gdb using "gdbreplay". See gdbserver/README for
3159 details. This is useful when you have a problem with GDB while doing
3160 remote debugging; you can make a recording of the session and send it
3161 to someone else, who can then recreate the problem.
3163 * Speedups for remote debugging
3165 GDB includes speedups for downloading and stepping MIPS systems using
3166 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3167 and more efficient S-record downloading.
3169 * Memory use reductions and statistics collection
3171 GDB now uses less memory and reports statistics about memory usage.
3172 Try the `maint print statistics' command, for example.
3174 *** Changes in GDB-4.15:
3176 * Psymtabs for XCOFF
3178 The symbol reader for AIX GDB now uses partial symbol tables. This
3179 can greatly improve startup time, especially for large executables.
3181 * Remote targets use caching
3183 Remote targets now use a data cache to speed up communication with the
3184 remote side. The data cache could lead to incorrect results because
3185 it doesn't know about volatile variables, thus making it impossible to
3186 debug targets which use memory mapped I/O devices. `set remotecache
3187 off' turns the the data cache off.
3189 * Remote targets may have threads
3191 The standard remote protocol now includes support for multiple threads
3192 in the target system, using new protocol commands 'H' and 'T'. See
3193 gdb/remote.c for details.
3197 If GDB is configured with `--enable-netrom', then it will include
3198 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3199 acts as though it is a bank of ROM on the target board, but you can
3200 write into it over the network. GDB's support consists only of
3201 support for fast loading into the emulated ROM; to debug, you must use
3202 another protocol, such as standard remote protocol. The usual
3203 sequence is something like
3205 target nrom <netrom-hostname>
3207 target remote <netrom-hostname>:1235
3211 GDB now includes support for the Apple Macintosh, as a host only. It
3212 may be run as either an MPW tool or as a standalone application, and
3213 it can debug through the serial port. All the usual GDB commands are
3214 available, but to the target command, you must supply "serial" as the
3215 device type instead of "/dev/ttyXX". See mpw-README in the main
3216 directory for more information on how to build. The MPW configuration
3217 scripts */mpw-config.in support only a few targets, and only the
3218 mips-idt-ecoff target has been tested.
3222 GDB configuration now uses autoconf. This is not user-visible,
3223 but does simplify configuration and building.
3227 GDB now supports hpux10.
3229 *** Changes in GDB-4.14:
3231 * New native configurations
3233 x86 FreeBSD i[345]86-*-freebsd
3234 x86 NetBSD i[345]86-*-netbsd
3235 NS32k NetBSD ns32k-*-netbsd
3236 Sparc NetBSD sparc-*-netbsd
3240 A29K VxWorks a29k-*-vxworks
3241 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3242 CPU32 EST-300 emulator m68*-*-est*
3243 PowerPC ELF powerpc-*-elf
3246 * Alpha OSF/1 support for procfs
3248 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3249 possible to attach to running processes. As the mounting of the /proc
3250 filesystem is optional on the Alpha, GDB automatically determines
3251 the availability of /proc during startup. This can lead to problems
3252 if /proc is unmounted after GDB has been started.
3254 * Arguments to user-defined commands
3256 User commands may accept up to 10 arguments separated by whitespace.
3257 Arguments are accessed within the user command via $arg0..$arg9. A
3260 print $arg0 + $arg1 + $arg2
3262 To execute the command use:
3265 Defines the command "adder" which prints the sum of its three arguments.
3266 Note the arguments are text substitutions, so they may reference variables,
3267 use complex expressions, or even perform inferior function calls.
3269 * New `if' and `while' commands
3271 This makes it possible to write more sophisticated user-defined
3272 commands. Both commands take a single argument, which is the
3273 expression to evaluate, and must be followed by the commands to
3274 execute, one per line, if the expression is nonzero, the list being
3275 terminated by the word `end'. The `if' command list may include an
3276 `else' word, which causes the following commands to be executed only
3277 if the expression is zero.
3279 * Fortran source language mode
3281 GDB now includes partial support for Fortran 77. It will recognize
3282 Fortran programs and can evaluate a subset of Fortran expressions, but
3283 variables and functions may not be handled correctly. GDB will work
3284 with G77, but does not yet know much about symbols emitted by other
3287 * Better HPUX support
3289 Most debugging facilities now work on dynamic executables for HPPAs
3290 running hpux9 or later. You can attach to running dynamically linked
3291 processes, but by default the dynamic libraries will be read-only, so
3292 for instance you won't be able to put breakpoints in them. To change
3293 that behavior do the following before running the program:
3299 This will cause the libraries to be mapped private and read-write.
3300 To revert to the normal behavior, do this:
3306 You cannot set breakpoints or examine data in the library until after
3307 the library is loaded if the function/data symbols do not have
3310 GDB can now also read debug symbols produced by the HP C compiler on
3311 HPPAs (sorry, no C++, Fortran or 68k support).
3313 * Target byte order now dynamically selectable
3315 You can choose which byte order to use with a target system, via the
3316 commands "set endian big" and "set endian little", and you can see the
3317 current setting by using "show endian". You can also give the command
3318 "set endian auto", in which case GDB will use the byte order
3319 associated with the executable. Currently, only embedded MIPS
3320 configurations support dynamic selection of target byte order.
3322 * New DOS host serial code
3324 This version uses DPMI interrupts to handle buffered I/O, so you
3325 no longer need to run asynctsr when debugging boards connected to
3328 *** Changes in GDB-4.13:
3330 * New "complete" command
3332 This lists all the possible completions for the rest of the line, if it
3333 were to be given as a command itself. This is intended for use by emacs.
3335 * Trailing space optional in prompt
3337 "set prompt" no longer adds a space for you after the prompt you set. This
3338 allows you to set a prompt which ends in a space or one that does not.
3340 * Breakpoint hit counts
3342 "info break" now displays a count of the number of times the breakpoint
3343 has been hit. This is especially useful in conjunction with "ignore"; you
3344 can ignore a large number of breakpoint hits, look at the breakpoint info
3345 to see how many times the breakpoint was hit, then run again, ignoring one
3346 less than that number, and this will get you quickly to the last hit of
3349 * Ability to stop printing at NULL character
3351 "set print null-stop" will cause GDB to stop printing the characters of
3352 an array when the first NULL is encountered. This is useful when large
3353 arrays actually contain only short strings.
3355 * Shared library breakpoints
3357 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3358 breakpoints in shared libraries before the executable is run.
3360 * Hardware watchpoints
3362 There is a new hardware breakpoint for the watch command for sparclite
3363 targets. See gdb/sparclite/hw_breakpoint.note.
3365 Hardware watchpoints are also now supported under GNU/Linux.
3369 Annotations have been added. These are for use with graphical interfaces,
3370 and are still experimental. Currently only gdba.el uses these.
3372 * Improved Irix 5 support
3374 GDB now works properly with Irix 5.2.
3376 * Improved HPPA support
3378 GDB now works properly with the latest GCC and GAS.
3380 * New native configurations
3382 Sequent PTX4 i[34]86-sequent-ptx4
3383 HPPA running OSF/1 hppa*-*-osf*
3384 Atari TT running SVR4 m68*-*-sysv4*
3385 RS/6000 LynxOS rs6000-*-lynxos*
3389 OS/9000 i[34]86-*-os9k
3390 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3393 * Hitachi SH7000 and E7000-PC ICE support
3395 There is now support for communicating with the Hitachi E7000-PC ICE.
3396 This is available automatically when GDB is configured for the SH.
3400 As usual, a variety of small fixes and improvements, both generic
3401 and configuration-specific. See the ChangeLog for more detail.
3403 *** Changes in GDB-4.12:
3405 * Irix 5 is now supported
3409 GDB-4.12 on the HPPA has a number of changes which make it unable
3410 to debug the output from the currently released versions of GCC and
3411 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3412 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3413 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3416 *** Changes in GDB-4.11:
3418 * User visible changes:
3422 The "set remotedebug" option is now consistent between the mips remote
3423 target, remote targets using the gdb-specific protocol, UDI (AMD's
3424 debug protocol for the 29k) and the 88k bug monitor. It is now an
3425 integer specifying a debug level (normally 0 or 1, but 2 means more
3426 debugging info for the mips target).
3428 * DEC Alpha native support
3430 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3431 debug info, but GDB works fairly well with the DEC compiler and should
3432 work with a future GCC release. See the README file for a few
3433 Alpha-specific notes.
3435 * Preliminary thread implementation
3437 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3439 * LynxOS native and target support for 386
3441 This release has been hosted on LynxOS 2.2, and also can be configured
3442 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3445 * Improvements in C++ mangling/demangling.
3447 This release has much better g++ debugging, specifically in name
3448 mangling/demangling, virtual function calls, print virtual table,
3449 call methods, ...etc.
3451 *** Changes in GDB-4.10:
3453 * User visible changes:
3455 Remote debugging using the GDB-specific (`target remote') protocol now
3456 supports the `load' command. This is only useful if you have some
3457 other way of getting the stub to the target system, and you can put it
3458 somewhere in memory where it won't get clobbered by the download.
3460 Filename completion now works.
3462 When run under emacs mode, the "info line" command now causes the
3463 arrow to point to the line specified. Also, "info line" prints
3464 addresses in symbolic form (as well as hex).
3466 All vxworks based targets now support a user settable option, called
3467 vxworks-timeout. This option represents the number of seconds gdb
3468 should wait for responses to rpc's. You might want to use this if
3469 your vxworks target is, perhaps, a slow software simulator or happens
3470 to be on the far side of a thin network line.
3474 This release contains support for using a DEC alpha as a GDB host for
3475 cross debugging. Native alpha debugging is not supported yet.
3478 *** Changes in GDB-4.9:
3482 This is the first GDB release which is accompanied by a matching testsuite.
3483 The testsuite requires installation of dejagnu, which should be available
3484 via ftp from most sites that carry GNU software.
3488 'Cfront' style demangling has had its name changed to 'ARM' style, to
3489 emphasize that it was written from the specifications in the C++ Annotated
3490 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3491 disclaimers, it still generated too much confusion with users attempting to
3492 use gdb with AT&T cfront.
3496 GDB now uses a standard remote interface to a simulator library.
3497 So far, the library contains simulators for the Zilog Z8001/2, the
3498 Hitachi H8/300, H8/500 and Super-H.
3500 * New targets supported
3502 H8/300 simulator h8300-hitachi-hms or h8300hms
3503 H8/500 simulator h8500-hitachi-hms or h8500hms
3504 SH simulator sh-hitachi-hms or sh
3505 Z8000 simulator z8k-zilog-none or z8ksim
3506 IDT MIPS board over serial line mips-idt-ecoff
3508 Cross-debugging to GO32 targets is supported. It requires a custom
3509 version of the i386-stub.c module which is integrated with the
3510 GO32 memory extender.
3512 * New remote protocols
3514 MIPS remote debugging protocol.
3516 * New source languages supported
3518 This version includes preliminary support for Chill, a Pascal like language
3519 used by telecommunications companies. Chill support is also being integrated
3520 into the GNU compiler, but we don't know when it will be publically available.
3523 *** Changes in GDB-4.8:
3525 * HP Precision Architecture supported
3527 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3528 version of this support was available as a set of patches from the
3529 University of Utah. GDB does not support debugging of programs
3530 compiled with the HP compiler, because HP will not document their file
3531 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3532 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3534 Many problems in the preliminary version have been fixed.
3536 * Faster and better demangling
3538 We have improved template demangling and fixed numerous bugs in the GNU style
3539 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3540 character types (wchar_t) are now supported. Demangling of each symbol is now
3541 only done once, and is cached when the symbol table for a file is read in.
3542 This results in a small increase in memory usage for C programs, a moderate
3543 increase in memory usage for C++ programs, and a fantastic speedup in
3546 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3547 from the specifications in the Annotated Reference Manual, which AT&T's
3548 compiler does not actually implement.
3550 * G++ multiple inheritance compiler problem
3552 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3553 inheritance lattices was reworked to properly discover ambiguities. We
3554 recently found an example which causes this new algorithm to fail in a
3555 very subtle way, producing bad debug information for those classes.
3556 The file 'gcc.patch' (in this directory) can be applied to gcc to
3557 circumvent the problem. A future GCC release will contain a complete
3560 The previous G++ debug info problem (mentioned below for the gdb-4.7
3561 release) is fixed in gcc version 2.3.2.
3563 * Improved configure script
3565 The `configure' script will now attempt to guess your system type if
3566 you don't supply a host system type. The old scheme of supplying a
3567 host system triplet is preferable over using this. All the magic is
3568 done in the new `config.guess' script. Examine it for details.
3570 We have also brought our configure script much more in line with the FSF's
3571 version. It now supports the --with-xxx options. In particular,
3572 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3573 The resulting GDB will not be able to read arbitrary object file formats --
3574 only the format ``expected'' to be used on the configured target system.
3575 We hope to make this the default in a future release.
3577 * Documentation improvements
3579 There's new internal documentation on how to modify GDB, and how to
3580 produce clean changes to the code. We implore people to read it
3581 before submitting changes.
3583 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3584 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3585 `info' files are also provided. To build `info' files from scratch,
3586 you will need the latest `makeinfo' release, which will be available in
3587 a future texinfo-X.Y release.
3589 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3590 We're not sure exactly which versions have this problem, but it has
3591 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3592 or better. If that isn't possible, there is a patch in
3593 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3594 around this problem.
3598 GDB now supports array constants that can be used in expressions typed in by
3599 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3600 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3603 The new directory `gdb/sparclite' contains a program that demonstrates
3604 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3606 * New native hosts supported
3608 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3609 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3611 * New targets supported
3613 AMD 29k family via UDI a29k-amd-udi or udi29k
3615 * New file formats supported
3617 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3618 HPUX core files, and SCO 3.2v2 core files.
3622 Attaching to processes now works again; thanks for the many bug reports.
3624 We have also stomped on a bunch of core dumps caused by
3625 printf_filtered("%s") problems.
3627 We eliminated a copyright problem on the rpc and ptrace header files
3628 for VxWorks, which was discovered at the last minute during the 4.7
3629 release. You should now be able to build a VxWorks GDB.
3631 You can now interrupt gdb while an attached process is running. This
3632 will cause the attached process to stop, and give control back to GDB.
3634 We fixed problems caused by using too many file descriptors
3635 for reading symbols from object files and libraries. This was
3636 especially a problem for programs that used many (~100) shared
3639 The `step' command now only enters a subroutine if there is line number
3640 information for the subroutine. Otherwise it acts like the `next'
3641 command. Previously, `step' would enter subroutines if there was
3642 any debugging information about the routine. This avoids problems
3643 when using `cc -g1' on MIPS machines.
3645 * Internal improvements
3647 GDB's internal interfaces have been improved to make it easier to support
3648 debugging of multiple languages in the future.
3650 GDB now uses a common structure for symbol information internally.
3651 Minimal symbols (derived from linkage symbols in object files), partial
3652 symbols (from a quick scan of debug information), and full symbols
3653 contain a common subset of information, making it easier to write
3654 shared code that handles any of them.
3656 * New command line options
3658 We now accept --silent as an alias for --quiet.
3662 The memory-mapped-malloc library is now licensed under the GNU Library
3663 General Public License.
3665 *** Changes in GDB-4.7:
3667 * Host/native/target split
3669 GDB has had some major internal surgery to untangle the support for
3670 hosts and remote targets. Now, when you configure GDB for a remote
3671 target, it will no longer load in all of the support for debugging
3672 local programs on the host. When fully completed and tested, this will
3673 ensure that arbitrary host/target combinations are possible.
3675 The primary conceptual shift is to separate the non-portable code in
3676 GDB into three categories. Host specific code is required any time GDB
3677 is compiled on that host, regardless of the target. Target specific
3678 code relates to the peculiarities of the target, but can be compiled on
3679 any host. Native specific code is everything else: it can only be
3680 built when the host and target are the same system. Child process
3681 handling and core file support are two common `native' examples.
3683 GDB's use of /proc for controlling Unix child processes is now cleaner.
3684 It has been split out into a single module under the `target_ops' vector,
3685 plus two native-dependent functions for each system that uses /proc.
3687 * New hosts supported
3689 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3690 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3691 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3693 * New targets supported
3695 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3696 68030 and CPU32 m68030-*-*, m68332-*-*
3698 * New native hosts supported
3700 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3701 (386bsd is not well tested yet)
3702 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3704 * New file formats supported
3706 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3707 supports reading of `a.out.adobe' object files, which are an a.out
3708 format extended with minimal information about multiple sections.
3712 `show copying' is the same as the old `info copying'.
3713 `show warranty' is the same as `info warrantee'.
3714 These were renamed for consistency. The old commands continue to work.
3716 `info handle' is a new alias for `info signals'.
3718 You can now define pre-command hooks, which attach arbitrary command
3719 scripts to any command. The commands in the hook will be executed
3720 prior to the user's command. You can also create a hook which will be
3721 executed whenever the program stops. See gdb.texinfo.
3725 We now deal with Cfront style name mangling, and can even extract type
3726 info from mangled symbols. GDB can automatically figure out which
3727 symbol mangling style your C++ compiler uses.
3729 Calling of methods and virtual functions has been improved as well.
3733 The crash that occured when debugging Sun Ansi-C compiled binaries is
3734 fixed. This was due to mishandling of the extra N_SO stabs output
3737 We also finally got Ultrix 4.2 running in house, and fixed core file
3738 support, with help from a dozen people on the net.
3740 John M. Farrell discovered that the reason that single-stepping was so
3741 slow on all of the Mips based platforms (primarily SGI and DEC) was
3742 that we were trying to demangle and lookup a symbol used for internal
3743 purposes on every instruction that was being stepped through. Changing
3744 the name of that symbol so that it couldn't be mistaken for a C++
3745 mangled symbol sped things up a great deal.
3747 Rich Pixley sped up symbol lookups in general by getting much smarter
3748 about when C++ symbol mangling is necessary. This should make symbol
3749 completion (TAB on the command line) much faster. It's not as fast as
3750 we'd like, but it's significantly faster than gdb-4.6.
3754 A new user controllable variable 'call_scratch_address' can
3755 specify the location of a scratch area to be used when GDB
3756 calls a function in the target. This is necessary because the
3757 usual method of putting the scratch area on the stack does not work
3758 in systems that have separate instruction and data spaces.
3760 We integrated changes to support the 29k UDI (Universal Debugger
3761 Interface), but discovered at the last minute that we didn't have all
3762 of the appropriate copyright paperwork. We are working with AMD to
3763 resolve this, and hope to have it available soon.
3767 We have sped up the remote serial line protocol, especially for targets
3768 with lots of registers. It now supports a new `expedited status' ('T')
3769 message which can be used in place of the existing 'S' status message.
3770 This allows the remote stub to send only the registers that GDB
3771 needs to make a quick decision about single-stepping or conditional
3772 breakpoints, eliminating the need to fetch the entire register set for
3773 each instruction being stepped through.
3775 The GDB remote serial protocol now implements a write-through cache for
3776 registers, only re-reading the registers if the target has run.
3778 There is also a new remote serial stub for SPARC processors. You can
3779 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3780 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3781 processor with a serial port.
3785 Configure.in files have become much easier to read and modify. A new
3786 `table driven' format makes it more obvious what configurations are
3787 supported, and what files each one uses.
3791 There is a new opcodes library which will eventually contain all of the
3792 disassembly routines and opcode tables. At present, it only contains
3793 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3794 disassembler (binutils/objdump) to share these routines.
3796 The libiberty library is now copylefted under the GNU Library General
3797 Public License. This allows more liberal use, and was done so libg++
3798 can use it. This makes no difference to GDB, since the Library License
3799 grants all the rights from the General Public License.
3803 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3804 reference to the stabs symbol info used by the debugger. It is (as far
3805 as we know) the only published document on this fascinating topic. We
3806 encourage you to read it, compare it to the stabs information on your
3807 system, and send improvements on the document in general (to
3808 bug-gdb@prep.ai.mit.edu).
3810 And, of course, many bugs have been fixed.
3813 *** Changes in GDB-4.6:
3815 * Better support for C++ function names
3817 GDB now accepts as input the "demangled form" of C++ overloaded function
3818 names and member function names, and can do command completion on such names
3819 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3820 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3821 Make use of command completion, it is your friend.
3823 GDB also now accepts a variety of C++ mangled symbol formats. They are
3824 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3825 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3826 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3827 for the list of formats.
3829 * G++ symbol mangling problem
3831 Recent versions of gcc have a bug in how they emit debugging information for
3832 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3833 directory) can be applied to gcc to fix the problem. Alternatively, if you
3834 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3835 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3836 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3839 * New 'maintenance' command
3841 All of the commands related to hacking GDB internals have been moved out of
3842 the main command set, and now live behind the 'maintenance' command. This
3843 can also be abbreviated as 'mt'. The following changes were made:
3845 dump-me -> maintenance dump-me
3846 info all-breakpoints -> maintenance info breakpoints
3847 printmsyms -> maintenance print msyms
3848 printobjfiles -> maintenance print objfiles
3849 printpsyms -> maintenance print psymbols
3850 printsyms -> maintenance print symbols
3852 The following commands are new:
3854 maintenance demangle Call internal GDB demangler routine to
3855 demangle a C++ link name and prints the result.
3856 maintenance print type Print a type chain for a given symbol
3858 * Change to .gdbinit file processing
3860 We now read the $HOME/.gdbinit file before processing the argv arguments
3861 (e.g. reading symbol files or core files). This allows global parameters to
3862 be set, which will apply during the symbol reading. The ./.gdbinit is still
3863 read after argv processing.
3865 * New hosts supported
3867 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3869 GNU/Linux support i386-unknown-linux or linux
3871 We are also including code to support the HP/PA running BSD and HPUX. This
3872 is almost guaranteed not to work, as we didn't have time to test or build it
3873 for this release. We are including it so that the more adventurous (or
3874 masochistic) of you can play with it. We also had major problems with the
3875 fact that the compiler that we got from HP doesn't support the -g option.
3878 * New targets supported
3880 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3882 * More smarts about finding #include files
3884 GDB now remembers the compilation directory for all include files, and for
3885 all files from which C is generated (like yacc and lex sources). This
3886 greatly improves GDB's ability to find yacc/lex sources, and include files,
3887 especially if you are debugging your program from a directory different from
3888 the one that contains your sources.
3890 We also fixed a bug which caused difficulty with listing and setting
3891 breakpoints in include files which contain C code. (In the past, you had to
3892 try twice in order to list an include file that you hadn't looked at before.)
3894 * Interesting infernals change
3896 GDB now deals with arbitrary numbers of sections, where the symbols for each
3897 section must be relocated relative to that section's landing place in the
3898 target's address space. This work was needed to support ELF with embedded
3899 stabs used by Solaris-2.0.
3901 * Bug fixes (of course!)
3903 There have been loads of fixes for the following things:
3904 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3905 i960, stabs, DOS(GO32), procfs, etc...
3907 See the ChangeLog for details.
3909 *** Changes in GDB-4.5:
3911 * New machines supported (host and target)
3913 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3915 SGI Irix-4.x mips-sgi-irix4 or iris4
3917 * New malloc package
3919 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3920 Mmalloc is capable of handling mutiple heaps of memory. It is also
3921 capable of saving a heap to a file, and then mapping it back in later.
3922 This can be used to greatly speedup the startup of GDB by using a
3923 pre-parsed symbol table which lives in a mmalloc managed heap. For
3924 more details, please read mmalloc/mmalloc.texi.
3928 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3929 'help info proc' for details.
3931 * MIPS ecoff symbol table format
3933 The code that reads MIPS symbol table format is now supported on all hosts.
3934 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3937 * File name changes for MS-DOS
3939 Many files in the config directories have been renamed to make it easier to
3940 support GDB on MS-DOSe systems (which have very restrictive file name
3941 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3942 environment) is close to working but has some remaining problems. Note
3943 that debugging of DOS programs is not supported, due to limitations
3944 in the ``operating system'', but it can be used to host cross-debugging.
3946 * Cross byte order fixes
3948 Many fixes have been made to support cross debugging of Sparc and MIPS
3949 targets from hosts whose byte order differs.
3951 * New -mapped and -readnow options
3953 If memory-mapped files are available on your system through the 'mmap'
3954 system call, you can use the -mapped option on the `file' or
3955 `symbol-file' commands to cause GDB to write the symbols from your
3956 program into a reusable file. If the program you are debugging is
3957 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3958 Future GDB debugging sessions will notice the presence of this file,
3959 and will quickly map in symbol information from it, rather than reading
3960 the symbol table from the executable program. Using the '-mapped'
3961 option in a GDB `file' or `symbol-file' command has the same effect as
3962 starting GDB with the '-mapped' command-line option.
3964 You can cause GDB to read the entire symbol table immediately by using
3965 the '-readnow' option with any of the commands that load symbol table
3966 information (or on the GDB command line). This makes the command
3967 slower, but makes future operations faster.
3969 The -mapped and -readnow options are typically combined in order to
3970 build a `fred.syms' file that contains complete symbol information.
3971 A simple GDB invocation to do nothing but build a `.syms' file for future
3974 gdb -batch -nx -mapped -readnow programname
3976 The `.syms' file is specific to the host machine on which GDB is run.
3977 It holds an exact image of GDB's internal symbol table. It cannot be
3978 shared across multiple host platforms.
3980 * longjmp() handling
3982 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3983 siglongjmp() without losing control. This feature has not yet been ported to
3984 all systems. It currently works on many 386 platforms, all MIPS-based
3985 platforms (SGI, DECstation, etc), and Sun3/4.
3989 Preliminary work has been put in to support the new Solaris OS from Sun. At
3990 this time, it can control and debug processes, but it is not capable of
3995 As always, many many bug fixes. The major areas were with g++, and mipsread.
3996 People using the MIPS-based platforms should experience fewer mysterious
3997 crashes and trashed symbol tables.
3999 *** Changes in GDB-4.4:
4001 * New machines supported (host and target)
4003 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4005 BSD Reno on Vax vax-dec-bsd
4006 Ultrix on Vax vax-dec-ultrix
4008 * New machines supported (target)
4010 AMD 29000 embedded, using EBMON a29k-none-none
4014 GDB continues to improve its handling of C++. `References' work better.
4015 The demangler has also been improved, and now deals with symbols mangled as
4016 per the Annotated C++ Reference Guide.
4018 GDB also now handles `stabs' symbol information embedded in MIPS
4019 `ecoff' symbol tables. Since the ecoff format was not easily
4020 extensible to handle new languages such as C++, this appeared to be a
4021 good way to put C++ debugging info into MIPS binaries. This option
4022 will be supported in the GNU C compiler, version 2, when it is
4025 * New features for SVR4
4027 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4028 shared libraries. Debugging dynamically linked programs should present
4029 only minor differences from debugging statically linked programs.
4031 The `info proc' command will print out information about any process
4032 on an SVR4 system (including the one you are debugging). At the moment,
4033 it prints the address mappings of the process.
4035 If you bring up GDB on another SVR4 system, please send mail to
4036 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4038 * Better dynamic linking support in SunOS
4040 Reading symbols from shared libraries which contain debugging symbols
4041 now works properly. However, there remain issues such as automatic
4042 skipping of `transfer vector' code during function calls, which
4043 make it harder to debug code in a shared library, than to debug the
4044 same code linked statically.
4048 GDB is now using the latest `getopt' routines from the FSF. This
4049 version accepts the -- prefix for options with long names. GDB will
4050 continue to accept the old forms (-option and +option) as well.
4051 Various single letter abbreviations for options have been explicity
4052 added to the option table so that they won't get overshadowed in the
4053 future by other options that begin with the same letter.
4057 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4058 Many assorted bugs have been handled. Many more remain to be handled.
4059 See the various ChangeLog files (primarily in gdb and bfd) for details.
4062 *** Changes in GDB-4.3:
4064 * New machines supported (host and target)
4066 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4067 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4068 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4070 * Almost SCO Unix support
4072 We had hoped to support:
4073 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4074 (except for core file support), but we discovered very late in the release
4075 that it has problems with process groups that render gdb unusable. Sorry
4076 about that. I encourage people to fix it and post the fixes.
4078 * Preliminary ELF and DWARF support
4080 GDB can read ELF object files on System V Release 4, and can handle
4081 debugging records for C, in DWARF format, in ELF files. This support
4082 is preliminary. If you bring up GDB on another SVR4 system, please
4083 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4088 GDB now uses the latest `readline' library. One user-visible change
4089 is that two tabs will list possible command completions, which previously
4090 required typing M-? (meta-question mark, or ESC ?).
4094 The `stepi' bug that many of you noticed has been squashed.
4095 Many bugs in C++ have been handled. Many more remain to be handled.
4096 See the various ChangeLog files (primarily in gdb and bfd) for details.
4098 * State of the MIPS world (in case you wondered):
4100 GDB can understand the symbol tables emitted by the compilers
4101 supplied by most vendors of MIPS-based machines, including DEC. These
4102 symbol tables are in a format that essentially nobody else uses.
4104 Some versions of gcc come with an assembler post-processor called
4105 mips-tfile. This program is required if you want to do source-level
4106 debugging of gcc-compiled programs. I believe FSF does not ship
4107 mips-tfile with gcc version 1, but it will eventually come with gcc
4110 Debugging of g++ output remains a problem. g++ version 1.xx does not
4111 really support it at all. (If you're lucky, you should be able to get
4112 line numbers and stack traces to work, but no parameters or local
4113 variables.) With some work it should be possible to improve the
4116 When gcc version 2 is released, you will have somewhat better luck.
4117 However, even then you will get confusing results for inheritance and
4120 We will eventually provide full debugging of g++ output on
4121 DECstations. This will probably involve some kind of stabs-in-ecoff
4122 encapulation, but the details have not been worked out yet.
4125 *** Changes in GDB-4.2:
4127 * Improved configuration
4129 Only one copy of `configure' exists now, and it is not self-modifying.
4130 Porting BFD is simpler.
4134 The `step' and `next' commands now only stop at the first instruction
4135 of a source line. This prevents the multiple stops that used to occur
4136 in switch statements, for-loops, etc. `Step' continues to stop if a
4137 function that has debugging information is called within the line.
4141 Lots of small bugs fixed. More remain.
4143 * New host supported (not target)
4145 Intel 386 PC clone running Mach i386-none-mach
4148 *** Changes in GDB-4.1:
4150 * Multiple source language support
4152 GDB now has internal scaffolding to handle several source languages.
4153 It determines the type of each source file from its filename extension,
4154 and will switch expression parsing and number formatting to match the
4155 language of the function in the currently selected stack frame.
4156 You can also specifically set the language to be used, with
4157 `set language c' or `set language modula-2'.
4161 GDB now has preliminary support for the GNU Modula-2 compiler,
4162 currently under development at the State University of New York at
4163 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4164 continue through the fall of 1991 and into 1992.
4166 Other Modula-2 compilers are currently not supported, and attempting to
4167 debug programs compiled with them will likely result in an error as the
4168 symbol table is read. Feel free to work on it, though!
4170 There are hooks in GDB for strict type checking and range checking,
4171 in the `Modula-2 philosophy', but they do not currently work.
4175 GDB can now write to executable and core files (e.g. patch
4176 a variable's value). You must turn this switch on, specify
4177 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4178 by assigning a new value to a variable. Modifications take
4181 * Automatic SunOS shared library reading
4183 When you run your program, GDB automatically determines where its
4184 shared libraries (if any) have been loaded, and reads their symbols.
4185 The `share' command is no longer needed. This also works when
4186 examining core files.
4190 You can specify the number of lines that the `list' command shows.
4193 * New machines supported (host and target)
4195 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4196 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4197 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4199 * New hosts supported (not targets)
4201 IBM RT/PC: romp-ibm-aix or rtpc
4203 * New targets supported (not hosts)
4205 AMD 29000 embedded with COFF a29k-none-coff
4206 AMD 29000 embedded with a.out a29k-none-aout
4207 Ultracomputer remote kernel debug a29k-nyu-kern
4209 * New remote interfaces
4215 *** Changes in GDB-4.0:
4219 Wide output is wrapped at good places to make the output more readable.
4221 Gdb now supports cross-debugging from a host machine of one type to a
4222 target machine of another type. Communication with the target system
4223 is over serial lines. The ``target'' command handles connecting to the
4224 remote system; the ``load'' command will download a program into the
4225 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4226 also supports debugging of realtime processes running under VxWorks,
4227 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4228 stub on the target system.
4230 New CPUs supported include the AMD 29000 and Intel 960.
4232 GDB now reads object files and symbol tables via a ``binary file''
4233 library, which allows a single copy of GDB to debug programs of multiple
4234 object file types such as a.out and coff.
4236 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4237 refcard.dvi and refcard.ps are available to format it).
4240 * Control-Variable user interface simplified
4242 All variables that control the operation of the debugger can be set
4243 by the ``set'' command, and displayed by the ``show'' command.
4245 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4246 ``Show prompt'' produces the response:
4247 Gdb's prompt is new-gdb=>.
4249 What follows are the NEW set commands. The command ``help set'' will
4250 print a complete list of old and new set commands. ``help set FOO''
4251 will give a longer description of the variable FOO. ``show'' will show
4252 all of the variable descriptions and their current settings.
4254 confirm on/off: Enables warning questions for operations that are
4255 hard to recover from, e.g. rerunning the program while
4256 it is already running. Default is ON.
4258 editing on/off: Enables EMACS style command line editing
4259 of input. Previous lines can be recalled with
4260 control-P, the current line can be edited with control-B,
4261 you can search for commands with control-R, etc.
4264 history filename NAME: NAME is where the gdb command history
4265 will be stored. The default is .gdb_history,
4266 or the value of the environment variable
4269 history size N: The size, in commands, of the command history. The
4270 default is 256, or the value of the environment variable
4273 history save on/off: If this value is set to ON, the history file will
4274 be saved after exiting gdb. If set to OFF, the
4275 file will not be saved. The default is OFF.
4277 history expansion on/off: If this value is set to ON, then csh-like
4278 history expansion will be performed on
4279 command line input. The default is OFF.
4281 radix N: Sets the default radix for input and output. It can be set
4282 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4283 in the current radix, so "set radix 10" is always a no-op.
4285 height N: This integer value is the number of lines on a page. Default
4286 is 24, the current `stty rows'' setting, or the ``li#''
4287 setting from the termcap entry matching the environment
4290 width N: This integer value is the number of characters on a line.
4291 Default is 80, the current `stty cols'' setting, or the ``co#''
4292 setting from the termcap entry matching the environment
4295 Note: ``set screensize'' is obsolete. Use ``set height'' and
4296 ``set width'' instead.
4298 print address on/off: Print memory addresses in various command displays,
4299 such as stack traces and structure values. Gdb looks
4300 more ``symbolic'' if you turn this off; it looks more
4301 ``machine level'' with it on. Default is ON.
4303 print array on/off: Prettyprint arrays. New convenient format! Default
4306 print demangle on/off: Print C++ symbols in "source" form if on,
4309 print asm-demangle on/off: Same, for assembler level printouts
4312 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4315 * Support for Epoch Environment.
4317 The epoch environment is a version of Emacs v18 with windowing. One
4318 new command, ``inspect'', is identical to ``print'', except that if you
4319 are running in the epoch environment, the value is printed in its own
4323 * Support for Shared Libraries
4325 GDB can now debug programs and core files that use SunOS shared libraries.
4326 Symbols from a shared library cannot be referenced
4327 before the shared library has been linked with the program (this
4328 happens after you type ``run'' and before the function main() is entered).
4329 At any time after this linking (including when examining core files
4330 from dynamically linked programs), gdb reads the symbols from each
4331 shared library when you type the ``sharedlibrary'' command.
4332 It can be abbreviated ``share''.
4334 sharedlibrary REGEXP: Load shared object library symbols for files
4335 matching a unix regular expression. No argument
4336 indicates to load symbols for all shared libraries.
4338 info sharedlibrary: Status of loaded shared libraries.
4343 A watchpoint stops execution of a program whenever the value of an
4344 expression changes. Checking for this slows down execution
4345 tremendously whenever you are in the scope of the expression, but is
4346 quite useful for catching tough ``bit-spreader'' or pointer misuse
4347 problems. Some machines such as the 386 have hardware for doing this
4348 more quickly, and future versions of gdb will use this hardware.
4350 watch EXP: Set a watchpoint (breakpoint) for an expression.
4352 info watchpoints: Information about your watchpoints.
4354 delete N: Deletes watchpoint number N (same as breakpoints).
4355 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4356 enable N: Re-enables watchpoint number N (same as breakpoints).
4359 * C++ multiple inheritance
4361 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4364 * C++ exception handling
4366 Gdb now supports limited C++ exception handling. Besides the existing
4367 ability to breakpoint on an exception handler, gdb can breakpoint on
4368 the raising of an exception (before the stack is peeled back to the
4371 catch FOO: If there is a FOO exception handler in the dynamic scope,
4372 set a breakpoint to catch exceptions which may be raised there.
4373 Multiple exceptions (``catch foo bar baz'') may be caught.
4375 info catch: Lists all exceptions which may be caught in the
4376 current stack frame.
4379 * Minor command changes
4381 The command ``call func (arg, arg, ...)'' now acts like the print
4382 command, except it does not print or save a value if the function's result
4383 is void. This is similar to dbx usage.
4385 The ``up'' and ``down'' commands now always print the frame they end up
4386 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4387 frames without printing.
4389 * New directory command
4391 'dir' now adds directories to the FRONT of the source search path.
4392 The path starts off empty. Source files that contain debug information
4393 about the directory in which they were compiled can be found even
4394 with an empty path; Sun CC and GCC include this information. If GDB can't
4395 find your source file in the current directory, type "dir .".
4397 * Configuring GDB for compilation
4399 For normal use, type ``./configure host''. See README or gdb.texinfo
4402 GDB now handles cross debugging. If you are remotely debugging between
4403 two different machines, type ``./configure host -target=targ''.
4404 Host is the machine where GDB will run; targ is the machine
4405 where the program that you are debugging will run.