1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.4
8 * GDB now handles ambiguous linespecs more consistently; the existing
9 FILE:LINE support has been expanded to other types of linespecs. A
10 breakpoint will now be set on all matching locations in all
11 inferiors, and locations will be added or removed according to
14 * GDB now allows you to skip uninteresting functions and files when
15 stepping with the "skip function" and "skip file" commands.
17 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
18 and "show remote hardware-watchpoint-length-limit". These allows to
19 set or show the maximum length limit (in bytes) of a remote
20 target hardware watchpoint.
22 This allows e.g. to use "unlimited" hardware watchpoints with the
23 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
24 watchpoints are slower than real hardware watchpoints but are
25 significantly faster than gdb software watchpoints.
29 ** The register_pretty_printer function in module gdb.printing now takes
30 an optional `replace' argument. If True, the new printer replaces any
33 ** The "maint set python print-stack on|off" command has been
34 removed. A new command: "set python print-stack
35 none|full|message" has replaced it. Additionally, the default
36 for "print-stack" is now "message", which just prints the error
37 message without the stack trace.
39 ** A prompt substitution hook (prompt_hook) is now available to the
42 ** A new Python module, gdb.prompt has been added to the GDB Python
43 modules library. This module provides functionality for
44 escape sequences in prompts (used by set/show
45 extended-prompt). These escape sequences are replaced by their
48 ** Python commands and convenience-functions located in
49 'data-directory'/python/gdb/command and
50 'data-directory'/python/gdb/function are now automatically loaded
53 ** Blocks now provide four new attributes. global_block and
54 static_block will return the global and static blocks
55 respectively. is_static and is_global are boolean attributes
56 that indicate if the block is one of those two types.
58 ** Symbols now provide the "type" attribute, the type of the symbol.
60 ** The "gdb.breakpoint" function has been deprecated in favor of
63 ** Type objects for struct and union types now allow access to
64 the fields using standard Python dictionary (mapping) methods.
65 For example, "some_type['myfield']" now works, as does
68 ** A new event "gdb.new_objfile" has been added, triggered by loading a
71 ** A new function, "deep_items" has been added to the gdb.types
72 module in the GDB Python modules library. This function returns
73 an iterator over the fields of a struct or union type. Unlike
74 the standard Python "iteritems" method, it will recursively traverse
79 ** "*stopped" events can report several new "reason"s, such as
82 ** Breakpoint changes are now notified using new async records, like
83 "=breakpoint-modified".
85 ** New command -ada-task-info.
87 * libthread-db-search-path now supports two special values: $sdir and $pdir.
88 $sdir specifies the default system locations of shared libraries.
89 $pdir specifies the directory where the libpthread used by the application
92 GDB no longer looks in $sdir and $pdir after it has searched the directories
93 mentioned in libthread-db-search-path. If you want to search those
94 directories, they must be specified in libthread-db-search-path.
95 The default value of libthread-db-search-path on GNU/Linux and Solaris
96 systems is now "$sdir:$pdir".
98 $pdir is not supported by gdbserver, it is currently ignored.
99 $sdir is supported by gdbserver.
101 * New configure option --with-iconv-bin.
102 When using the internationalization support like the one in the GNU C
103 library, GDB will invoke the "iconv" program to get a list of supported
104 character sets. If this program lives in a non-standard location, one can
105 use this option to specify where to find it.
107 * When natively debugging programs on PowerPC BookE processors running
108 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
109 watchpoints, which specify a mask in addition to an address to watch.
110 The mask specifies that some bits of an address (the bits which are
111 reset in the mask) should be ignored when matching the address accessed
112 by the inferior against the watchpoint address. See the "PowerPC Embedded"
113 section in the user manual for more details.
115 * The new option --once causes GDBserver to stop listening for connections once
116 the first connection is made. The listening port used by GDBserver will
117 become available after that.
119 * New commands "info macros" and "alias" have been added.
121 * New function parameters suffix @entry specifies value of function parameter
122 at the time the function got called. Entry values are available only since
128 "!" is now an alias of the "shell" command.
129 Note that no space is needed between "!" and SHELL COMMAND.
133 watch EXPRESSION mask MASK_VALUE
134 The watch command now supports the mask argument which allows creation
135 of masked watchpoints, if the current architecture supports this feature.
137 info auto-load-scripts [REGEXP]
138 This command was formerly named "maintenance print section-scripts".
139 It is now generally useful and is no longer a maintenance-only command.
141 info macro [-all] [--] MACRO
142 The info macro command has new options `-all' and `--'. The first for
143 printing all definitions of a macro. The second for explicitly specifying
144 the end of arguments and the beginning of the macro name in case the macro
145 name starts with a hyphen.
147 collect[/s] EXPRESSIONS
148 The tracepoint collect command now takes an optional modifier "/s"
149 that directs it to dereference pointer-to-character types and
150 collect the bytes of memory up to a zero byte. The behavior is
151 similar to what you see when you use the regular print command on a
152 string. An optional integer following the "/s" sets a bound on the
153 number of bytes that will be collected.
156 The trace start command now interprets any supplied arguments as a
157 note to be recorded with the trace run, with an effect similar to
158 setting the variable trace-notes.
161 The trace stop command now interprets any arguments as a note to be
162 mentioned along with the tstatus report that the trace was stopped
163 with a command. The effect is similar to setting the variable
166 * Tracepoints can now be enabled and disabled at any time after a trace
167 experiment has been started using the standard "enable" and "disable"
168 commands. It is now possible to start a trace experiment with no enabled
169 tracepoints; GDB will display a warning, but will allow the experiment to
170 begin, assuming that tracepoints will be enabled as needed while the trace
173 * Fast tracepoints on 32-bit x86-architectures can now be placed at
174 locations with 4-byte instructions, when they were previously
175 limited to locations with instructions of 5 bytes or longer.
181 Set the GDB prompt, and allow escape sequences to be inserted to
182 display miscellaneous information (see 'help set extended-prompt'
183 for the list of sequences). This prompt (and any information
184 accessed through the escape sequences) is updated every time the
187 set print entry-values (both|compact|default|if-needed|no|only|preferred)
188 show print entry-values
189 Set printing of frame argument values at function entry. In some cases
190 GDB can determine the value of function argument which was passed by the
191 function caller, even if the value was modified inside the called function.
193 set debug entry-values
194 show debug entry-values
195 Control display of debugging info for determining frame argument values at
196 function entry and virtual tail call frames.
198 set basenames-may-differ
199 show basenames-may-differ
200 Set whether a source file may have multiple base names.
201 (A "base name" is the name of a file with the directory part removed.
202 Example: The base name of "/home/user/hello.c" is "hello.c".)
203 If set, GDB will canonicalize file names (e.g., expand symlinks)
204 before comparing them. Canonicalization is an expensive operation,
205 but it allows the same file be known by more than one base name.
206 If not set (the default), all source files are assumed to have just
207 one base name, and gdb will do file name comparisons more efficiently.
213 Set a user name and notes for the current and any future trace runs.
214 This is useful for long-running and/or disconnected traces, to
215 inform others (or yourself) as to who is running the trace, supply
216 contact information, or otherwise explain what is going on.
219 show trace-stop-notes
220 Set a note attached to the trace run, that is displayed when the
221 trace has been stopped by a tstop command. This is useful for
222 instance as an explanation, if you are stopping a trace run that was
223 started by someone else.
229 Dynamically enable a tracepoint in a started trace experiment.
233 Dynamically disable a tracepoint in a started trace experiment.
237 Set the user and notes of the trace run.
241 Query the current status of a tracepoint.
245 Query the minimum length of instruction at which a fast tracepoint may
248 * Dcache size (number of lines) and line-size are now runtime-configurable
249 via "set dcache line" and "set dcache line-size" commands.
253 Texas Instruments TMS320C6x tic6x-*-*
257 Renesas RL78 rl78-*-elf
259 *** Changes in GDB 7.3.1
261 * The build failure for NetBSD and OpenBSD targets have now been fixed.
263 *** Changes in GDB 7.3
265 * GDB has a new command: "thread find [REGEXP]".
266 It finds the thread id whose name, target id, or thread extra info
267 matches the given regular expression.
269 * The "catch syscall" command now works on mips*-linux* targets.
271 * The -data-disassemble MI command now supports modes 2 and 3 for
272 dumping the instruction opcodes.
274 * New command line options
276 -data-directory DIR Specify DIR as the "data-directory".
277 This is mostly for testing purposes.
279 * The "maint set python auto-load on|off" command has been renamed to
280 "set auto-load-scripts on|off".
282 * GDB has a new command: "set directories".
283 It is like the "dir" command except that it replaces the
284 source path list instead of augmenting it.
286 * GDB now understands thread names.
288 On GNU/Linux, "info threads" will display the thread name as set by
289 prctl or pthread_setname_np.
291 There is also a new command, "thread name", which can be used to
292 assign a name internally for GDB to display.
295 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
296 has been integrated into GDB.
300 ** The function gdb.Write now accepts an optional keyword 'stream'.
301 This keyword, when provided, will direct the output to either
302 stdout, stderr, or GDB's logging output.
304 ** Parameters can now be be sub-classed in Python, and in particular
305 you may implement the get_set_doc and get_show_doc functions.
306 This improves how Parameter set/show documentation is processed
307 and allows for more dynamic content.
309 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
310 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
311 have an is_valid method.
313 ** Breakpoints can now be sub-classed in Python, and in particular
314 you may implement a 'stop' function that is executed each time
315 the inferior reaches that breakpoint.
317 ** New function gdb.lookup_global_symbol looks up a global symbol.
319 ** GDB values in Python are now callable if the value represents a
320 function. For example, if 'some_value' represents a function that
321 takes two integer parameters and returns a value, you can call
322 that function like so:
324 result = some_value (10,20)
326 ** Module gdb.types has been added.
327 It contains a collection of utilities for working with gdb.Types objects:
328 get_basic_type, has_field, make_enum_dict.
330 ** Module gdb.printing has been added.
331 It contains utilities for writing and registering pretty-printers.
332 New classes: PrettyPrinter, SubPrettyPrinter,
333 RegexpCollectionPrettyPrinter.
334 New function: register_pretty_printer.
336 ** New commands "info pretty-printers", "enable pretty-printer" and
337 "disable pretty-printer" have been added.
339 ** gdb.parameter("directories") is now available.
341 ** New function gdb.newest_frame returns the newest frame in the
344 ** The gdb.InferiorThread class has a new "name" attribute. This
345 holds the thread's name.
347 ** Python Support for Inferior events.
348 Python scripts can add observers to be notified of events
349 occurring in the process being debugged.
350 The following events are currently supported:
351 - gdb.events.cont Continue event.
352 - gdb.events.exited Inferior exited event.
353 - gdb.events.stop Signal received, and Breakpoint hit events.
357 ** GDB now puts template parameters in scope when debugging in an
358 instantiation. For example, if you have:
360 template<int X> int func (void) { return X; }
362 then if you step into func<5>, "print X" will show "5". This
363 feature requires proper debuginfo support from the compiler; it
364 was added to GCC 4.5.
366 ** The motion commands "next", "finish", "until", and "advance" now
367 work better when exceptions are thrown. In particular, GDB will
368 no longer lose control of the inferior; instead, the GDB will
369 stop the inferior at the point at which the exception is caught.
370 This functionality requires a change in the exception handling
371 code that was introduced in GCC 4.5.
373 * GDB now follows GCC's rules on accessing volatile objects when
374 reading or writing target state during expression evaluation.
375 One notable difference to prior behavior is that "print x = 0"
376 no longer generates a read of x; the value of the assignment is
377 now always taken directly from the value being assigned.
379 * GDB now has some support for using labels in the program's source in
380 linespecs. For instance, you can use "advance label" to continue
381 execution to a label.
383 * GDB now has support for reading and writing a new .gdb_index
384 section. This section holds a fast index of DWARF debugging
385 information and can be used to greatly speed up GDB startup and
386 operation. See the documentation for `save gdb-index' for details.
388 * The "watch" command now accepts an optional "-location" argument.
389 When used, this causes GDB to watch the memory referred to by the
390 expression. Such a watchpoint is never deleted due to it going out
393 * GDB now supports thread debugging of core dumps on GNU/Linux.
395 GDB now activates thread debugging using the libthread_db library
396 when debugging GNU/Linux core dumps, similarly to when debugging
397 live processes. As a result, when debugging a core dump file, GDB
398 is now able to display pthread_t ids of threads. For example, "info
399 threads" shows the same output as when debugging the process when it
400 was live. In earlier releases, you'd see something like this:
403 * 1 LWP 6780 main () at main.c:10
405 While now you see this:
408 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
410 It is also now possible to inspect TLS variables when debugging core
413 When debugging a core dump generated on a machine other than the one
414 used to run GDB, you may need to point GDB at the correct
415 libthread_db library with the "set libthread-db-search-path"
416 command. See the user manual for more details on this command.
418 * When natively debugging programs on PowerPC BookE processors running
419 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
420 which stop execution of the inferior whenever it executes an instruction
421 at any address within the specified range. See the "PowerPC Embedded"
422 section in the user manual for more details.
424 * New features in the GDB remote stub, GDBserver
426 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
427 and i686 LynxOS (version 5.x).
429 ** GDBserver is now supported on Blackfin Linux.
431 * New native configurations
433 ia64 HP-UX ia64-*-hpux*
437 Analog Devices, Inc. Blackfin Processor bfin-*
439 * Ada task switching is now supported on sparc-elf targets when
440 debugging a program using the Ravenscar Profile. For more information,
441 see the "Tasking Support when using the Ravenscar Profile" section
442 in the GDB user manual.
444 * Guile support was removed.
446 * New features in the GNU simulator
448 ** The --map-info flag lists all known core mappings.
450 ** CFI flashes may be simulated via the "cfi" device.
452 *** Changes in GDB 7.2
454 * Shared library support for remote targets by default
456 When GDB is configured for a generic, non-OS specific target, like
457 for example, --target=arm-eabi or one of the many *-*-elf targets,
458 GDB now queries remote stubs for loaded shared libraries using the
459 `qXfer:libraries:read' packet. Previously, shared library support
460 was always disabled for such configurations.
464 ** Argument Dependent Lookup (ADL)
466 In C++ ADL lookup directs function search to the namespaces of its
467 arguments even if the namespace has not been imported.
477 Here the compiler will search for `foo' in the namespace of 'b'
478 and find A::foo. GDB now supports this. This construct is commonly
479 used in the Standard Template Library for operators.
481 ** Improved User Defined Operator Support
483 In addition to member operators, GDB now supports lookup of operators
484 defined in a namespace and imported with a `using' directive, operators
485 defined in the global scope, operators imported implicitly from an
486 anonymous namespace, and the ADL operators mentioned in the previous
488 GDB now also supports proper overload resolution for all the previously
489 mentioned flavors of operators.
491 ** static const class members
493 Printing of static const class members that are initialized in the
494 class definition has been fixed.
496 * Windows Thread Information Block access.
498 On Windows targets, GDB now supports displaying the Windows Thread
499 Information Block (TIB) structure. This structure is visible either
500 by using the new command `info w32 thread-information-block' or, by
501 dereferencing the new convenience variable named `$_tlb', a
502 thread-specific pointer to the TIB. This feature is also supported
503 when remote debugging using GDBserver.
507 Static tracepoints are calls in the user program into a tracing
508 library. One such library is a port of the LTTng kernel tracer to
509 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
510 When debugging with GDBserver, GDB now supports combining the GDB
511 tracepoint machinery with such libraries. For example: the user can
512 use GDB to probe a static tracepoint marker (a call from the user
513 program into the tracing library) with the new "strace" command (see
514 "New commands" below). This creates a "static tracepoint" in the
515 breakpoint list, that can be manipulated with the same feature set
516 as fast and regular tracepoints. E.g., collect registers, local and
517 global variables, collect trace state variables, and define
518 tracepoint conditions. In addition, the user can collect extra
519 static tracepoint marker specific data, by collecting the new
520 $_sdata internal variable. When analyzing the trace buffer, you can
521 inspect $_sdata like any other variable available to GDB. For more
522 information, see the "Tracepoints" chapter in GDB user manual. New
523 remote packets have been defined to support static tracepoints, see
524 the "New remote packets" section below.
526 * Better reconstruction of tracepoints after disconnected tracing
528 GDB will attempt to download the original source form of tracepoint
529 definitions when starting a trace run, and then will upload these
530 upon reconnection to the target, resulting in a more accurate
531 reconstruction of the tracepoints that are in use on the target.
535 You can now exercise direct control over the ways that GDB can
536 affect your program. For instance, you can disallow the setting of
537 breakpoints, so that the program can run continuously (assuming
538 non-stop mode). In addition, the "observer" variable is available
539 to switch all of the different controls; in observer mode, GDB
540 cannot affect the target's behavior at all, which is useful for
541 tasks like diagnosing live systems in the field.
543 * The new convenience variable $_thread holds the number of the
550 Return the address of the Windows Thread Information Block of a given thread.
554 In response to several of the tracepoint packets, the target may now
555 also respond with a number of intermediate `qRelocInsn' request
556 packets before the final result packet, to have GDB handle
557 relocating an instruction to execute at a different address. This
558 is particularly useful for stubs that support fast tracepoints. GDB
559 reports support for this feature in the qSupported packet.
563 List static tracepoint markers in the target program.
567 List static tracepoint markers at a given address in the target
570 qXfer:statictrace:read
572 Read the static trace data collected (by a `collect $_sdata'
573 tracepoint action). The remote stub reports support for this packet
574 to gdb's qSupported query.
578 Send the current settings of GDB's permission flags.
582 Send part of the source (textual) form of a tracepoint definition,
583 which includes location, conditional, and action list.
585 * The source command now accepts a -s option to force searching for the
586 script in the source search path even if the script name specifies
589 * New features in the GDB remote stub, GDBserver
591 - GDBserver now support tracepoints (including fast tracepoints, and
592 static tracepoints). The feature is currently supported by the
593 i386-linux and amd64-linux builds. See the "Tracepoints support
594 in gdbserver" section in the manual for more information.
596 GDBserver JIT compiles the tracepoint's conditional agent
597 expression bytecode into native code whenever possible for low
598 overhead dynamic tracepoints conditionals. For such tracepoints,
599 an expression that examines program state is evaluated when the
600 tracepoint is reached, in order to determine whether to capture
601 trace data. If the condition is simple and false, processing the
602 tracepoint finishes very quickly and no data is gathered.
604 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
605 for static tracepoints support.
607 - GDBserver now supports x86_64 Windows 64-bit debugging.
609 * GDB now sends xmlRegisters= in qSupported packet to indicate that
610 it understands register description.
612 * The --batch flag now disables pagination and queries.
614 * X86 general purpose registers
616 GDB now supports reading/writing byte, word and double-word x86
617 general purpose registers directly. This means you can use, say,
618 $ah or $ax to refer, respectively, to the byte register AH and
619 16-bit word register AX that are actually portions of the 32-bit
620 register EAX or 64-bit register RAX.
622 * The `commands' command now accepts a range of breakpoints to modify.
623 A plain `commands' following a command that creates multiple
624 breakpoints affects all the breakpoints set by that command. This
625 applies to breakpoints set by `rbreak', and also applies when a
626 single `break' command creates multiple breakpoints (e.g.,
627 breakpoints on overloaded c++ functions).
629 * The `rbreak' command now accepts a filename specification as part of
630 its argument, limiting the functions selected by the regex to those
631 in the specified file.
633 * Support for remote debugging Windows and SymbianOS shared libraries
634 from Unix hosts has been improved. Non Windows GDB builds now can
635 understand target reported file names that follow MS-DOS based file
636 system semantics, such as file names that include drive letters and
637 use the backslash character as directory separator. This makes it
638 possible to transparently use the "set sysroot" and "set
639 solib-search-path" on Unix hosts to point as host copies of the
640 target's shared libraries. See the new command "set
641 target-file-system-kind" described below, and the "Commands to
642 specify files" section in the user manual for more information.
646 eval template, expressions...
647 Convert the values of one or more expressions under the control
648 of the string template to a command line, and call it.
650 set target-file-system-kind unix|dos-based|auto
651 show target-file-system-kind
652 Set or show the assumed file system kind for target reported file
655 save breakpoints <filename>
656 Save all current breakpoint definitions to a file suitable for use
657 in a later debugging session. To read the saved breakpoint
658 definitions, use the `source' command.
660 `save tracepoints' is a new alias for `save-tracepoints'. The latter
663 info static-tracepoint-markers
664 Display information about static tracepoint markers in the target.
666 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
667 Define a static tracepoint by probing a marker at the given
668 function, line, address, or marker ID.
672 Enable and disable observer mode.
674 set may-write-registers on|off
675 set may-write-memory on|off
676 set may-insert-breakpoints on|off
677 set may-insert-tracepoints on|off
678 set may-insert-fast-tracepoints on|off
679 set may-interrupt on|off
680 Set individual permissions for GDB effects on the target. Note that
681 some of these settings can have undesirable or surprising
682 consequences, particularly when changed in the middle of a session.
683 For instance, disabling the writing of memory can prevent
684 breakpoints from being inserted, cause single-stepping to fail, or
685 even crash your program, if you disable after breakpoints have been
686 inserted. However, GDB should not crash.
688 set record memory-query on|off
689 show record memory-query
690 Control whether to stop the inferior if memory changes caused
691 by an instruction cannot be recorded.
696 The disassemble command now supports "start,+length" form of two arguments.
700 ** GDB now provides a new directory location, called the python directory,
701 where Python scripts written for GDB can be installed. The location
702 of that directory is <data-directory>/python, where <data-directory>
703 is the GDB data directory. For more details, see section `Scripting
704 GDB using Python' in the manual.
706 ** The GDB Python API now has access to breakpoints, symbols, symbol
707 tables, program spaces, inferiors, threads and frame's code blocks.
708 Additionally, GDB Parameters can now be created from the API, and
709 manipulated via set/show in the CLI.
711 ** New functions gdb.target_charset, gdb.target_wide_charset,
712 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
714 ** New exception gdb.GdbError.
716 ** Pretty-printers are now also looked up in the current program space.
718 ** Pretty-printers can now be individually enabled and disabled.
720 ** GDB now looks for names of Python scripts to auto-load in a
721 special section named `.debug_gdb_scripts', in addition to looking
722 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
724 * Tracepoint actions were unified with breakpoint commands. In particular,
725 there are no longer differences in "info break" output for breakpoints and
726 tracepoints and the "commands" command can be used for both tracepoints and
731 ARM Symbian arm*-*-symbianelf*
733 * D language support.
734 GDB now supports debugging programs written in the D programming
737 * GDB now supports the extended ptrace interface for PowerPC which is
738 available since Linux kernel version 2.6.34. This automatically enables
739 any hardware breakpoints and additional hardware watchpoints available in
740 the processor. The old ptrace interface exposes just one hardware
741 watchpoint and no hardware breakpoints.
743 * GDB is now able to use the Data Value Compare (DVC) register available on
744 embedded PowerPC processors to implement in hardware simple watchpoint
745 conditions of the form:
747 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
749 This works in native GDB running on Linux kernels with the extended ptrace
750 interface mentioned above.
752 *** Changes in GDB 7.1
758 GDB now supports importing of namespaces in C++. This enables the
759 user to inspect variables from imported namespaces. Support for
760 namepace aliasing has also been added. So, if a namespace is
761 aliased in the current scope (e.g. namepace C=A; ) the user can
762 print variables using the alias (e.g. (gdb) print C::x).
766 All known bugs relating to the printing of virtual base class were
767 fixed. It is now possible to call overloaded static methods using a
772 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
773 and reinterpret_cast<> are now handled by the C++ expression parser.
777 Xilinx MicroBlaze microblaze-*-*
782 Xilinx MicroBlaze microblaze
785 * Multi-program debugging.
787 GDB now has support for multi-program (a.k.a. multi-executable or
788 multi-exec) debugging. This allows for debugging multiple inferiors
789 simultaneously each running a different program under the same GDB
790 session. See "Debugging Multiple Inferiors and Programs" in the
791 manual for more information. This implied some user visible changes
792 in the multi-inferior support. For example, "info inferiors" now
793 lists inferiors that are not running yet or that have exited
794 already. See also "New commands" and "New options" below.
796 * New tracing features
798 GDB's tracepoint facility now includes several new features:
800 ** Trace state variables
802 GDB tracepoints now include support for trace state variables, which
803 are variables managed by the target agent during a tracing
804 experiment. They are useful for tracepoints that trigger each
805 other, so for instance one tracepoint can count hits in a variable,
806 and then a second tracepoint has a condition that is true when the
807 count reaches a particular value. Trace state variables share the
808 $-syntax of GDB convenience variables, and can appear in both
809 tracepoint actions and condition expressions. Use the "tvariable"
810 command to create, and "info tvariables" to view; see "Trace State
811 Variables" in the manual for more detail.
815 GDB now includes an option for defining fast tracepoints, which
816 targets may implement more efficiently, such as by installing a jump
817 into the target agent rather than a trap instruction. The resulting
818 speedup can be by two orders of magnitude or more, although the
819 tradeoff is that some program locations on some target architectures
820 might not allow fast tracepoint installation, for instance if the
821 instruction to be replaced is shorter than the jump. To request a
822 fast tracepoint, use the "ftrace" command, with syntax identical to
823 the regular trace command.
825 ** Disconnected tracing
827 It is now possible to detach GDB from the target while it is running
828 a trace experiment, then reconnect later to see how the experiment
829 is going. In addition, a new variable disconnected-tracing lets you
830 tell the target agent whether to continue running a trace if the
831 connection is lost unexpectedly.
835 GDB now has the ability to save the trace buffer into a file, and
836 then use that file as a target, similarly to you can do with
837 corefiles. You can select trace frames, print data that was
838 collected in them, and use tstatus to display the state of the
839 tracing run at the moment that it was saved. To create a trace
840 file, use "tsave <filename>", and to use it, do "target tfile
843 ** Circular trace buffer
845 You can ask the target agent to handle the trace buffer as a
846 circular buffer, discarding the oldest trace frames to make room for
847 newer ones, by setting circular-trace-buffer to on. This feature may
848 not be available for all target agents.
853 The disassemble command, when invoked with two arguments, now requires
854 the arguments to be comma-separated.
857 The info variables command now displays variable definitions. Files
858 which only declare a variable are not shown.
861 The source command is now capable of sourcing Python scripts.
862 This feature is dependent on the debugger being build with Python
865 Related to this enhancement is also the introduction of a new command
866 "set script-extension" (see below).
868 * New commands (for set/show, see "New options" below)
870 record save [<FILENAME>]
871 Save a file (in core file format) containing the process record
872 execution log for replay debugging at a later time.
874 record restore <FILENAME>
875 Restore the process record execution log that was saved at an
876 earlier time, for replay debugging.
878 add-inferior [-copies <N>] [-exec <FILENAME>]
881 clone-inferior [-copies <N>] [ID]
882 Make a new inferior ready to execute the same program another
888 maint info program-spaces
889 List the program spaces loaded into GDB.
891 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
892 show remote interrupt-sequence
893 Allow the user to select one of ^C, a BREAK signal or BREAK-g
894 as the sequence to the remote target in order to interrupt the execution.
895 Ctrl-C is a default. Some system prefers BREAK which is high level of
896 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
897 Magic SysRq g. It is BREAK signal and character 'g'.
899 set remote interrupt-on-connect [on | off]
900 show remote interrupt-on-connect
901 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
902 remote target when gdb connects to it. This is needed when you debug
905 set remotebreak [on | off]
907 Deprecated. Use "set/show remote interrupt-sequence" instead.
909 tvariable $NAME [ = EXP ]
910 Create or modify a trace state variable.
913 List trace state variables and their values.
915 delete tvariable $NAME ...
916 Delete one or more trace state variables.
919 Evaluate the given expressions without collecting anything into the
920 trace buffer. (Valid in tracepoint actions only.)
922 ftrace FN / FILE:LINE / *ADDR
923 Define a fast tracepoint at the given function, line, or address.
925 * New expression syntax
927 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
928 GDB now parses 0b101010 identically with 42.
932 set follow-exec-mode new|same
933 show follow-exec-mode
934 Control whether GDB reuses the same inferior across an exec call or
935 creates a new one. This is useful to be able to restart the old
936 executable after the inferior having done an exec call.
938 set default-collect EXPR, ...
940 Define a list of expressions to be collected at each tracepoint.
941 This is a useful way to ensure essential items are not overlooked,
942 such as registers or a critical global variable.
944 set disconnected-tracing
945 show disconnected-tracing
946 If set to 1, the target is instructed to continue tracing if it
947 loses its connection to GDB. If 0, the target is to stop tracing
950 set circular-trace-buffer
951 show circular-trace-buffer
952 If set to on, the target is instructed to use a circular trace buffer
953 and discard the oldest trace frames instead of stopping the trace due
954 to a full trace buffer. If set to off, the trace stops when the buffer
955 fills up. Some targets may not support this.
957 set script-extension off|soft|strict
958 show script-extension
959 If set to "off", the debugger does not perform any script language
960 recognition, and all sourced files are assumed to be GDB scripts.
961 If set to "soft" (the default), files are sourced according to
962 filename extension, falling back to GDB scripts if the first
964 If set to "strict", files are sourced according to filename extension.
966 set ada trust-PAD-over-XVS on|off
967 show ada trust-PAD-over-XVS
968 If off, activate a workaround against a bug in the debugging information
969 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
970 the GCC sources for more information about the GNAT encoding and
971 PAD types in particular). It is always safe to set this option to
972 off, but this introduces a slight performance penalty. The default
975 * Python API Improvements
977 ** GDB provides the new class gdb.LazyString. This is useful in
978 some pretty-printing cases. The new method gdb.Value.lazy_string
979 provides a simple way to create objects of this type.
981 ** The fields returned by gdb.Type.fields now have an
982 `is_base_class' attribute.
984 ** The new method gdb.Type.range returns the range of an array type.
986 ** The new method gdb.parse_and_eval can be used to parse and
987 evaluate an expression.
992 Define a trace state variable.
995 Get the current value of a trace state variable.
998 Set desired tracing behavior upon disconnection.
1001 Set the trace buffer to be linear or circular.
1004 Get data about the tracepoints currently in use.
1008 Process record now works correctly with hardware watchpoints.
1010 Multiple bug fixes have been made to the mips-irix port, making it
1011 much more reliable. In particular:
1012 - Debugging threaded applications is now possible again. Previously,
1013 GDB would hang while starting the program, or while waiting for
1014 the program to stop at a breakpoint.
1015 - Attaching to a running process no longer hangs.
1016 - An error occurring while loading a core file has been fixed.
1017 - Changing the value of the PC register now works again. This fixes
1018 problems observed when using the "jump" command, or when calling
1019 a function from GDB, or even when assigning a new value to $pc.
1020 - With the "finish" and "return" commands, the return value for functions
1021 returning a small array is now correctly printed.
1022 - It is now possible to break on shared library code which gets executed
1023 during a shared library init phase (code executed while executing
1024 their .init section). Previously, the breakpoint would have no effect.
1025 - GDB is now able to backtrace through the signal handler for
1026 non-threaded programs.
1028 PIE (Position Independent Executable) programs debugging is now supported.
1029 This includes debugging execution of PIC (Position Independent Code) shared
1030 libraries although for that, it should be possible to run such libraries as an
1033 *** Changes in GDB 7.0
1035 * GDB now has an interface for JIT compilation. Applications that
1036 dynamically generate code can create symbol files in memory and register
1037 them with GDB. For users, the feature should work transparently, and
1038 for JIT developers, the interface is documented in the GDB manual in the
1039 "JIT Compilation Interface" chapter.
1041 * Tracepoints may now be conditional. The syntax is as for
1042 breakpoints; either an "if" clause appended to the "trace" command,
1043 or the "condition" command is available. GDB sends the condition to
1044 the target for evaluation using the same bytecode format as is used
1045 for tracepoint actions.
1047 * The disassemble command now supports: an optional /r modifier, print the
1048 raw instructions in hex as well as in symbolic form, and an optional /m
1049 modifier to print mixed source+assembly.
1051 * Process record and replay
1053 In a architecture environment that supports ``process record and
1054 replay'', ``process record and replay'' target can record a log of
1055 the process execution, and replay it with both forward and reverse
1058 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1059 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1060 set execution-direction {forward|reverse}, for targets that support
1063 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1064 feature is available with a native GDB running on kernel version
1067 * GDB now has support for multi-byte and wide character sets on the
1068 target. Strings whose character type is wchar_t, char16_t, or
1069 char32_t are now correctly printed. GDB supports wide- and unicode-
1070 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1071 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1072 `printf'. This feature requires iconv to work properly; if your
1073 system does not have a working iconv, GDB can use GNU libiconv. See
1074 the installation instructions for more information.
1076 * GDB now supports automatic retrieval of shared library files from
1077 remote targets. To use this feature, specify a system root that begins
1078 with the `remote:' prefix, either via the `set sysroot' command or via
1079 the `--with-sysroot' configure-time option.
1081 * "info sharedlibrary" now takes an optional regex of libraries to show,
1082 and it now reports if a shared library has no debugging information.
1084 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1085 now complete on file names.
1087 * When completing in expressions, gdb will attempt to limit
1088 completions to allowable structure or union fields, where appropriate.
1089 For instance, consider:
1091 # struct example { int f1; double f2; };
1092 # struct example variable;
1095 If the user types TAB at the end of this command line, the available
1096 completions will be "f1" and "f2".
1098 * Inlined functions are now supported. They show up in backtraces, and
1099 the "step", "next", and "finish" commands handle them automatically.
1101 * GDB now supports the token-splicing (##) and stringification (#)
1102 operators when expanding macros. It also supports variable-arity
1105 * GDB now supports inspecting extra signal information, exported by
1106 the new $_siginfo convenience variable. The feature is currently
1107 implemented on linux ARM, i386 and amd64.
1109 * GDB can now display the VFP floating point registers and NEON vector
1110 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1111 can provide these registers (requires Linux 2.6.30 or later). Remote
1112 and simulator targets may also provide them.
1114 * New remote packets
1117 Search memory for a sequence of bytes.
1120 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1121 operation over reliable transport links. Use of this packet is
1122 controlled by the `set remote noack-packet' command.
1125 Kill the process with the specified process ID. Use this in preference
1126 to `k' when multiprocess protocol extensions are supported.
1129 Obtains additional operating system information
1133 Read or write additional signal information.
1135 * Removed remote protocol undocumented extension
1137 An undocumented extension to the remote protocol's `S' stop reply
1138 packet that permited the stub to pass a process id was removed.
1139 Remote servers should use the `T' stop reply packet instead.
1141 * GDB now supports multiple function calling conventions according to the
1142 DWARF-2 DW_AT_calling_convention function attribute.
1144 * The SH target utilizes the aforementioned change to distinguish between gcc
1145 and Renesas calling convention. It also adds the new CLI commands
1146 `set/show sh calling-convention'.
1148 * GDB can now read compressed debug sections, as produced by GNU gold
1149 with the --compress-debug-sections=zlib flag.
1151 * 64-bit core files are now supported on AIX.
1153 * Thread switching is now supported on Tru64.
1155 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1156 which will be allocated using malloc later in program execution.
1158 * The qXfer:libraries:read remote procotol packet now allows passing a
1159 list of section offsets.
1161 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1162 conditions handling signals delivered during attach or thread creation
1163 have also been fixed.
1165 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1166 From the user's standpoint, all unqualified instances of True and False
1167 are treated as the standard definitions, regardless of context.
1169 * GDB now parses C++ symbol and type names more flexibly. For
1172 template<typename T> class C { };
1175 GDB will now correctly handle all of:
1177 ptype C<char const *>
1178 ptype C<char const*>
1179 ptype C<const char *>
1180 ptype C<const char*>
1182 * New features in the GDB remote stub, gdbserver
1184 - The "--wrapper" command-line argument tells gdbserver to use a
1185 wrapper program to launch programs for debugging.
1187 - On PowerPC and S/390 targets, it is now possible to use a single
1188 gdbserver executable to debug both 32-bit and 64-bit programs.
1189 (This requires gdbserver itself to be built as a 64-bit executable.)
1191 - gdbserver uses the new noack protocol mode for TCP connections to
1192 reduce communications latency, if also supported and enabled in GDB.
1194 - Support for the sparc64-linux-gnu target is now included in
1197 - The amd64-linux build of gdbserver now supports debugging both
1198 32-bit and 64-bit programs.
1200 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1201 now support hardware watchpoints, and will use them automatically
1206 GDB now has support for scripting using Python. Whether this is
1207 available is determined at configure time.
1209 New GDB commands can now be written in Python.
1211 * Ada tasking support
1213 Ada tasks can now be inspected in GDB. The following commands have
1217 Print the list of Ada tasks.
1219 Print detailed information about task number N.
1221 Print the task number of the current task.
1223 Switch the context of debugging to task number N.
1225 * Support for user-defined prefixed commands. The "define" command can
1226 add new commands to existing prefixes, e.g. "target".
1228 * Multi-inferior, multi-process debugging.
1230 GDB now has generalized support for multi-inferior debugging. See
1231 "Debugging Multiple Inferiors" in the manual for more information.
1232 Although availability still depends on target support, the command
1233 set is more uniform now. The GNU/Linux specific multi-forks support
1234 has been migrated to this new framework. This implied some user
1235 visible changes; see "New commands" and also "Removed commands"
1238 * Target descriptions can now describe the target OS ABI. See the
1239 "Target Description Format" section in the user manual for more
1242 * Target descriptions can now describe "compatible" architectures
1243 to indicate that the target can execute applications for a different
1244 architecture in addition to those for the main target architecture.
1245 See the "Target Description Format" section in the user manual for
1248 * Multi-architecture debugging.
1250 GDB now includes general supports for debugging applications on
1251 hybrid systems that use more than one single processor architecture
1252 at the same time. Each such hybrid architecture still requires
1253 specific support to be added. The only hybrid architecture supported
1254 in this version of GDB is the Cell Broadband Engine.
1256 * GDB now supports integrated debugging of Cell/B.E. applications that
1257 use both the PPU and SPU architectures. To enable support for hybrid
1258 Cell/B.E. debugging, you need to configure GDB to support both the
1259 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1260 --enable-targets configure option.
1262 * Non-stop mode debugging.
1264 For some targets, GDB now supports an optional mode of operation in
1265 which you can examine stopped threads while other threads continue
1266 to execute freely. This is referred to as non-stop mode, with the
1267 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1268 section in the user manual for more information.
1270 To be able to support remote non-stop debugging, a remote stub needs
1271 to implement the non-stop mode remote protocol extensions, as
1272 described in the "Remote Non-Stop" section of the user manual. The
1273 GDB remote stub, gdbserver, has been adjusted to support these
1274 extensions on linux targets.
1276 * New commands (for set/show, see "New options" below)
1278 catch syscall [NAME(S) | NUMBER(S)]
1279 Catch system calls. Arguments, which should be names of system
1280 calls or their numbers, mean catch only those syscalls. Without
1281 arguments, every syscall will be caught. When the inferior issues
1282 any of the specified syscalls, GDB will stop and announce the system
1283 call, both when it is called and when its call returns. This
1284 feature is currently available with a native GDB running on the
1285 Linux Kernel, under the following architectures: x86, x86_64,
1286 PowerPC and PowerPC64.
1288 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1290 Search memory for a sequence of bytes.
1292 maint set python print-stack
1293 maint show python print-stack
1294 Show a stack trace when an error is encountered in a Python script.
1297 Invoke CODE by passing it to the Python interpreter.
1302 These allow macros to be defined, undefined, and listed
1306 Show operating system information about processes.
1309 List the inferiors currently under GDB's control.
1312 Switch focus to inferior number NUM.
1315 Detach from inferior number NUM.
1318 Kill inferior number NUM.
1322 set spu stop-on-load
1323 show spu stop-on-load
1324 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1326 set spu auto-flush-cache
1327 show spu auto-flush-cache
1328 Control whether to automatically flush the software-managed cache
1329 during Cell/B.E. debugging.
1331 set sh calling-convention
1332 show sh calling-convention
1333 Control the calling convention used when calling SH target functions.
1336 show debug timestamp
1337 Control display of timestamps with GDB debugging output.
1339 set disassemble-next-line
1340 show disassemble-next-line
1341 Control display of disassembled source lines or instructions when
1344 set remote noack-packet
1345 show remote noack-packet
1346 Set/show the use of remote protocol QStartNoAckMode packet. See above
1347 under "New remote packets."
1349 set remote query-attached-packet
1350 show remote query-attached-packet
1351 Control use of remote protocol `qAttached' (query-attached) packet.
1353 set remote read-siginfo-object
1354 show remote read-siginfo-object
1355 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1358 set remote write-siginfo-object
1359 show remote write-siginfo-object
1360 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1363 set remote reverse-continue
1364 show remote reverse-continue
1365 Control use of remote protocol 'bc' (reverse-continue) packet.
1367 set remote reverse-step
1368 show remote reverse-step
1369 Control use of remote protocol 'bs' (reverse-step) packet.
1371 set displaced-stepping
1372 show displaced-stepping
1373 Control displaced stepping mode. Displaced stepping is a way to
1374 single-step over breakpoints without removing them from the debuggee.
1375 Also known as "out-of-line single-stepping".
1378 show debug displaced
1379 Control display of debugging info for displaced stepping.
1381 maint set internal-error
1382 maint show internal-error
1383 Control what GDB does when an internal error is detected.
1385 maint set internal-warning
1386 maint show internal-warning
1387 Control what GDB does when an internal warning is detected.
1392 Use a wrapper program to launch programs for debugging.
1394 set multiple-symbols (all|ask|cancel)
1395 show multiple-symbols
1396 The value of this variable can be changed to adjust the debugger behavior
1397 when an expression or a breakpoint location contains an ambiguous symbol
1398 name (an overloaded function name, for instance).
1400 set breakpoint always-inserted
1401 show breakpoint always-inserted
1402 Keep breakpoints always inserted in the target, as opposed to inserting
1403 them when resuming the target, and removing them when the target stops.
1404 This option can improve debugger performance on slow remote targets.
1406 set arm fallback-mode (arm|thumb|auto)
1407 show arm fallback-mode
1408 set arm force-mode (arm|thumb|auto)
1410 These commands control how ARM GDB determines whether instructions
1411 are ARM or Thumb. The default for both settings is auto, which uses
1412 the current CPSR value for instructions without symbols; previous
1413 versions of GDB behaved as if "set arm fallback-mode arm".
1415 set disable-randomization
1416 show disable-randomization
1417 Standalone programs run with the virtual address space randomization enabled
1418 by default on some platforms. This option keeps the addresses stable across
1419 multiple debugging sessions.
1423 Control whether other threads are stopped or not when some thread hits
1428 Requests that asynchronous execution is enabled in the target, if available.
1429 In this case, it's possible to resume target in the background, and interact
1430 with GDB while the target is running. "show target-async" displays the
1431 current state of asynchronous execution of the target.
1433 set target-wide-charset
1434 show target-wide-charset
1435 The target-wide-charset is the name of the character set that GDB
1436 uses when printing characters whose type is wchar_t.
1438 set tcp auto-retry (on|off)
1440 set tcp connect-timeout
1441 show tcp connect-timeout
1442 These commands allow GDB to retry failed TCP connections to a remote stub
1443 with a specified timeout period; this is useful if the stub is launched
1444 in parallel with GDB but may not be ready to accept connections immediately.
1446 set libthread-db-search-path
1447 show libthread-db-search-path
1448 Control list of directories which GDB will search for appropriate
1451 set schedule-multiple (on|off)
1452 show schedule-multiple
1453 Allow GDB to resume all threads of all processes or only threads of
1454 the current process.
1458 Use more aggressive caching for accesses to the stack. This improves
1459 performance of remote debugging (particularly backtraces) without
1460 affecting correctness.
1462 set interactive-mode (on|off|auto)
1463 show interactive-mode
1464 Control whether GDB runs in interactive mode (on) or not (off).
1465 When in interactive mode, GDB waits for the user to answer all
1466 queries. Otherwise, GDB does not wait and assumes the default
1467 answer. When set to auto (the default), GDB determines which
1468 mode to use based on the stdin settings.
1473 For program forks, this is replaced by the new more generic `info
1474 inferiors' command. To list checkpoints, you can still use the
1475 `info checkpoints' command, which was an alias for the `info forks'
1479 Replaced by the new `inferior' command. To switch between
1480 checkpoints, you can still use the `restart' command, which was an
1481 alias for the `fork' command.
1484 This is removed, since some targets don't have a notion of
1485 processes. To switch between processes, you can still use the
1486 `inferior' command using GDB's own inferior number.
1489 For program forks, this is replaced by the new more generic `kill
1490 inferior' command. To delete a checkpoint, you can still use the
1491 `delete checkpoint' command, which was an alias for the `delete
1495 For program forks, this is replaced by the new more generic `detach
1496 inferior' command. To detach a checkpoint, you can still use the
1497 `detach checkpoint' command, which was an alias for the `detach
1500 * New native configurations
1502 x86/x86_64 Darwin i[34567]86-*-darwin*
1504 x86_64 MinGW x86_64-*-mingw*
1508 Lattice Mico32 lm32-*
1509 x86 DICOS i[34567]86-*-dicos*
1510 x86_64 DICOS x86_64-*-dicos*
1513 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1514 (mingw32ce) debugging.
1520 These commands were actually not implemented on any target.
1522 *** Changes in GDB 6.8
1524 * New native configurations
1526 NetBSD/hppa hppa*-*netbsd*
1527 Xtensa GNU/Linux xtensa*-*-linux*
1531 NetBSD/hppa hppa*-*-netbsd*
1532 Xtensa GNU/Lunux xtensa*-*-linux*
1534 * Change in command line behavior -- corefiles vs. process ids.
1536 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1537 attaching to process NUMBER fails, GDB no longer attempts to open a
1538 core file named NUMBER. Attaching to a program using the -c option
1539 is no longer supported. Instead, use the '-p' or '--pid' options.
1541 * GDB can now be built as a native debugger for debugging Windows x86
1542 (mingw32) Portable Executable (PE) programs.
1544 * Pending breakpoints no longer change their number when their address
1547 * GDB now supports breakpoints with multiple locations,
1548 including breakpoints on C++ constructors, inside C++ templates,
1549 and in inlined functions.
1551 * GDB's ability to debug optimized code has been improved. GDB more
1552 accurately identifies function bodies and lexical blocks that occupy
1553 more than one contiguous range of addresses.
1555 * Target descriptions can now describe registers for PowerPC.
1557 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1558 registers on PowerPC targets.
1560 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1561 targets even when the libthread_db library is not available.
1563 * The GDB remote stub, gdbserver, now supports the new file transfer
1564 commands (remote put, remote get, and remote delete).
1566 * The GDB remote stub, gdbserver, now supports run and attach in
1567 extended-remote mode.
1569 * hppa*64*-*-hpux11* target broken
1570 The debugger is unable to start a program and fails with the following
1571 error: "Error trying to get information about dynamic linker".
1572 The gdb-6.7 release is also affected.
1574 * GDB now supports the --enable-targets= configure option to allow
1575 building a single GDB executable that supports multiple remote
1576 target architectures.
1578 * GDB now supports debugging C and C++ programs which use the
1579 Decimal Floating Point extension. In addition, the PowerPC target
1580 now has a set of pseudo-registers to inspect decimal float values
1581 stored in two consecutive float registers.
1583 * The -break-insert MI command can optionally create pending
1586 * Improved support for debugging Ada
1587 Many improvements to the Ada language support have been made. These
1589 - Better support for Ada2005 interface types
1590 - Improved handling of arrays and slices in general
1591 - Better support for Taft-amendment types
1592 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1594 - Improved command completion in Ada
1597 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1602 set print frame-arguments (all|scalars|none)
1603 show print frame-arguments
1604 The value of this variable can be changed to control which argument
1605 values should be printed by the debugger when displaying a frame.
1610 Transfer files to and from a remote target, and delete remote files.
1617 Transfer files to and from a remote target, and delete remote files.
1619 * New remote packets
1626 Open, close, read, write, and delete files on the remote system.
1629 Attach to an existing process on the remote system, in extended-remote
1633 Run a new process on the remote system, in extended-remote mode.
1635 *** Changes in GDB 6.7
1637 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1638 bfd, libiberty and opcodes, as revealed by static analysis donated by
1639 Coverity, Inc. (http://scan.coverity.com).
1641 * When looking up multiply-defined global symbols, GDB will now prefer the
1642 symbol definition in the current shared library if it was built using the
1643 -Bsymbolic linker option.
1645 * When the Text User Interface (TUI) is not configured, GDB will now
1646 recognize the -tui command-line option and print a message that the TUI
1649 * The GDB remote stub, gdbserver, now has lower overhead for high
1650 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1652 * GDB for MIPS targets now autodetects whether a remote target provides
1653 32-bit or 64-bit register values.
1655 * Support for C++ member pointers has been improved.
1657 * GDB now understands XML target descriptions, which specify the
1658 target's overall architecture. GDB can read a description from
1659 a local file or over the remote serial protocol.
1661 * Vectors of single-byte data use a new integer type which is not
1662 automatically displayed as character or string data.
1664 * The /s format now works with the print command. It displays
1665 arrays of single-byte integers and pointers to single-byte integers
1668 * Target descriptions can now describe target-specific registers,
1669 for architectures which have implemented the support (currently
1670 only ARM, M68K, and MIPS).
1672 * GDB and the GDB remote stub, gdbserver, now support the XScale
1675 * The GDB remote stub, gdbserver, has been updated to support
1676 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1677 has been rewritten to use the standard GDB remote protocol.
1679 * GDB can now step into C++ functions which are called through thunks.
1681 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1683 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1684 layout. It also supports a TextSeg= and DataSeg= response when only
1685 segment base addresses (rather than offsets) are available.
1687 * The /i format now outputs any trailing branch delay slot instructions
1688 immediately following the last instruction within the count specified.
1690 * The GDB remote protocol "T" stop reply packet now supports a
1691 "library" response. Combined with the new "qXfer:libraries:read"
1692 packet, this response allows GDB to debug shared libraries on targets
1693 where the operating system manages the list of loaded libraries (e.g.
1694 Windows and SymbianOS).
1696 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1697 (DLLs) on Windows and Windows CE targets.
1699 * GDB now supports a faster verification that a .debug file matches its binary
1700 according to its build-id signature, if the signature is present.
1706 Enable or disable hardware flow control (RTS/CTS) on the serial port
1707 when debugging using remote targets.
1709 set mem inaccessible-by-default
1710 show mem inaccessible-by-default
1711 If the target supplies a memory map, for instance via the remote
1712 protocol's "qXfer:memory-map:read" packet, setting this variable
1713 prevents GDB from accessing memory outside the memory map. This
1714 is useful for targets with memory mapped registers or which react
1715 badly to accesses of unmapped address space.
1717 set breakpoint auto-hw
1718 show breakpoint auto-hw
1719 If the target supplies a memory map, for instance via the remote
1720 protocol's "qXfer:memory-map:read" packet, setting this variable
1721 lets GDB use hardware breakpoints automatically for memory regions
1722 where it can not use software breakpoints. This covers both the
1723 "break" command and internal breakpoints used for other commands
1724 including "next" and "finish".
1727 catch exception unhandled
1728 Stop the program execution when Ada exceptions are raised.
1731 Stop the program execution when an Ada assertion failed.
1735 Set an alternate system root for target files. This is a more
1736 general version of "set solib-absolute-prefix", which is now
1737 an alias to "set sysroot".
1740 Provide extended SPU facility status information. This set of
1741 commands is available only when debugging the Cell/B.E. SPU
1744 * New native configurations
1746 OpenBSD/sh sh*-*openbsd*
1749 unset tdesc filename
1751 Use the specified local file as an XML target description, and do
1752 not query the target for its built-in description.
1756 OpenBSD/sh sh*-*-openbsd*
1757 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1758 Toshiba Media Processor mep-elf
1760 * New remote packets
1763 Ignore the specified signals; pass them directly to the debugged program
1764 without stopping other threads or reporting them to GDB.
1766 qXfer:features:read:
1767 Read an XML target description from the target, which describes its
1772 Read or write contents of an spufs file on the target system. These
1773 packets are available only on the Cell/B.E. SPU architecture.
1775 qXfer:libraries:read:
1776 Report the loaded shared libraries. Combined with new "T" packet
1777 response, this packet allows GDB to debug shared libraries on
1778 targets where the operating system manages the list of loaded
1779 libraries (e.g. Windows and SymbianOS).
1783 Support for these obsolete configurations has been removed.
1791 i[34567]86-*-lynxos*
1792 i[34567]86-*-netware*
1793 i[34567]86-*-sco3.2v5*
1794 i[34567]86-*-sco3.2v4*
1796 i[34567]86-*-sysv4.2*
1799 i[34567]86-*-unixware2*
1800 i[34567]86-*-unixware*
1809 * Other removed features
1816 Various m68k-only ROM monitors.
1823 Various Renesas ROM monitors and debugging interfaces for SH and
1828 Support for a Macraigor serial interface to on-chip debugging.
1829 GDB does not directly support the newer parallel or USB
1834 A debug information format. The predecessor to DWARF 2 and
1835 DWARF 3, which are still supported.
1837 Support for the HP aCC compiler on HP-UX/PA-RISC
1839 SOM-encapsulated symbolic debugging information, automatic
1840 invocation of pxdb, and the aCC custom C++ ABI. This does not
1841 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1842 with aCC can still be debugged on an assembly level.
1844 MIPS ".pdr" sections
1846 A MIPS-specific format used to describe stack frame layout
1847 in debugging information.
1851 GDB could work with an older version of Guile to debug
1852 the interpreter and Scheme programs running in it.
1854 set mips stack-arg-size
1855 set mips saved-gpreg-size
1857 Use "set mips abi" to control parameter passing for MIPS.
1859 *** Changes in GDB 6.6
1864 Cell Broadband Engine SPU spu-elf
1866 * GDB can now be configured as a cross-debugger targeting native Windows
1867 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1868 running on a Windows system over TCP/IP to debug Windows programs.
1870 * The GDB remote stub, gdbserver, has been updated to support Windows and
1871 Cygwin debugging. Both single-threaded and multi-threaded programs are
1874 * The "set trust-readonly-sections" command works again. This command was
1875 broken in GDB 6.3, 6.4, and 6.5.
1877 * The "load" command now supports writing to flash memory, if the remote
1878 stub provides the required support.
1880 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1881 longer requires symbolic debug information (e.g. DWARF-2).
1886 unset substitute-path
1887 show substitute-path
1888 Manage a list of substitution rules that GDB uses to rewrite the name
1889 of the directories where the sources are located. This can be useful
1890 for instance when the sources were moved to a different location
1891 between compilation and debugging.
1895 Print each CLI command as it is executed. Each command is prefixed with
1896 a number of `+' symbols representing the nesting depth.
1897 The source command now has a `-v' option to enable the same feature.
1901 The ARM Demon monitor support (RDP protocol, "target rdp").
1903 Kernel Object Display, an embedded debugging feature which only worked with
1904 an obsolete version of Cisco IOS.
1906 The 'set download-write-size' and 'show download-write-size' commands.
1908 * New remote packets
1911 Tell a stub about GDB client features, and request remote target features.
1912 The first feature implemented is PacketSize, which allows the target to
1913 specify the size of packets it can handle - to minimize the number of
1914 packets required and improve performance when connected to a remote
1918 Fetch an OS auxilliary vector from the remote stub. This packet is a
1919 more efficient replacement for qPart:auxv:read.
1921 qXfer:memory-map:read:
1922 Fetch a memory map from the remote stub, including information about
1923 RAM, ROM, and flash memory devices.
1928 Erase and program a flash memory device.
1930 * Removed remote packets
1933 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1934 used it, and only gdbserver implemented it.
1936 *** Changes in GDB 6.5
1940 Renesas M32C/M16C m32c-elf
1942 Morpho Technologies ms1 ms1-elf
1946 init-if-undefined Initialize a convenience variable, but
1947 only if it doesn't already have a value.
1949 The following commands are presently only implemented for native GNU/Linux:
1951 checkpoint Save a snapshot of the program state.
1953 restart <n> Return the program state to a
1954 previously saved state.
1956 info checkpoints List currently saved checkpoints.
1958 delete-checkpoint <n> Delete a previously saved checkpoint.
1960 set|show detach-on-fork Tell gdb whether to detach from a newly
1961 forked process, or to keep debugging it.
1963 info forks List forks of the user program that
1964 are available to be debugged.
1966 fork <n> Switch to debugging one of several
1967 forks of the user program that are
1968 available to be debugged.
1970 delete-fork <n> Delete a fork from the list of forks
1971 that are available to be debugged (and
1972 kill the forked process).
1974 detach-fork <n> Delete a fork from the list of forks
1975 that are available to be debugged (and
1976 allow the process to continue).
1980 Morpho Technologies ms2 ms1-elf
1982 * Improved Windows host support
1984 GDB now builds as a cross debugger hosted on i686-mingw32, including
1985 native console support, and remote communications using either
1986 network sockets or serial ports.
1988 * Improved Modula-2 language support
1990 GDB can now print most types in the Modula-2 syntax. This includes:
1991 basic types, set types, record types, enumerated types, range types,
1992 pointer types and ARRAY types. Procedure var parameters are correctly
1993 printed and hexadecimal addresses and character constants are also
1994 written in the Modula-2 syntax. Best results can be obtained by using
1995 GNU Modula-2 together with the -gdwarf-2 command line option.
1999 The ARM rdi-share module.
2001 The Netware NLM debug server.
2003 *** Changes in GDB 6.4
2005 * New native configurations
2007 OpenBSD/arm arm*-*-openbsd*
2008 OpenBSD/mips64 mips64-*-openbsd*
2012 Morpho Technologies ms1 ms1-elf
2014 * New command line options
2016 --batch-silent As for --batch, but totally silent.
2017 --return-child-result The debugger will exist with the same value
2018 the child (debugged) program exited with.
2019 --eval-command COMMAND, -ex COMMAND
2020 Execute a single GDB CLI command. This may be
2021 specified multiple times and in conjunction
2022 with the --command (-x) option.
2024 * Deprecated commands removed
2026 The following commands, that were deprecated in 2000, have been
2030 set|show arm disassembly-flavor set|show arm disassembler
2031 othernames set arm disassembler
2032 set|show remotedebug set|show debug remote
2033 set|show archdebug set|show debug arch
2034 set|show eventdebug set|show debug event
2037 * New BSD user-level threads support
2039 It is now possible to debug programs using the user-level threads
2040 library on OpenBSD and FreeBSD. Currently supported (target)
2043 FreeBSD/amd64 x86_64-*-freebsd*
2044 FreeBSD/i386 i386-*-freebsd*
2045 OpenBSD/i386 i386-*-openbsd*
2047 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2048 are not yet supported.
2050 * New support for Matsushita MN10300 w/sim added
2051 (Work in progress). mn10300-elf.
2053 * REMOVED configurations and files
2055 VxWorks and the XDR protocol *-*-vxworks
2056 Motorola MCORE mcore-*-*
2057 National Semiconductor NS32000 ns32k-*-*
2059 * New "set print array-indexes" command
2061 After turning this setting "on", GDB prints the index of each element
2062 when displaying arrays. The default is "off" to preserve the previous
2065 * VAX floating point support
2067 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2069 * User-defined command support
2071 In addition to using $arg0..$arg9 for argument passing, it is now possible
2072 to use $argc to determine now many arguments have been passed. See the
2073 section on user-defined commands in the user manual for more information.
2075 *** Changes in GDB 6.3:
2077 * New command line option
2079 GDB now accepts -l followed by a number to set the timeout for remote
2082 * GDB works with GCC -feliminate-dwarf2-dups
2084 GDB now supports a more compact representation of DWARF-2 debug
2085 information using DW_FORM_ref_addr references. These are produced
2086 by GCC with the option -feliminate-dwarf2-dups and also by some
2087 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2088 to use -feliminate-dwarf2-dups.
2090 * Internationalization
2092 When supported by the host system, GDB will be built with
2093 internationalization (libintl). The task of marking up the sources is
2094 continued, we're looking forward to our first translation.
2098 Initial support for debugging programs compiled with the GNAT
2099 implementation of the Ada programming language has been integrated
2100 into GDB. In this release, support is limited to expression evaluation.
2102 * New native configurations
2104 GNU/Linux/m32r m32r-*-linux-gnu
2108 GDB's remote protocol now includes support for the 'p' packet. This
2109 packet is used to fetch individual registers from a remote inferior.
2111 * END-OF-LIFE registers[] compatibility module
2113 GDB's internal register infrastructure has been completely rewritten.
2114 The new infrastructure making possible the implementation of key new
2115 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2118 GDB 6.3 will be the last release to include the the registers[]
2119 compatibility module that allowed out-of-date configurations to
2120 continue to work. This change directly impacts the following
2130 powerpc bdm protocol
2132 Unless there is activity to revive these configurations, they will be
2133 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2135 * OBSOLETE configurations and files
2137 Configurations that have been declared obsolete in this release have
2138 been commented out. Unless there is activity to revive these
2139 configurations, the next release of GDB will have their sources
2140 permanently REMOVED.
2149 *** Changes in GDB 6.2.1:
2151 * MIPS `break main; run' gave an heuristic-fence-post warning
2153 When attempting to run even a simple program, a warning about
2154 heuristic-fence-post being hit would be reported. This problem has
2157 * MIPS IRIX 'long double' crashed GDB
2159 When examining a long double variable, GDB would get a segmentation
2160 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2161 IRIX long double values).
2165 A bug in the VAX stack code was causing problems with the "next"
2166 command. This problem has been fixed.
2168 *** Changes in GDB 6.2:
2170 * Fix for ``many threads''
2172 On GNU/Linux systems that use the NPTL threads library, a program
2173 rapidly creating and deleting threads would confuse GDB leading to the
2176 ptrace: No such process.
2177 thread_db_get_info: cannot get thread info: generic error
2179 This problem has been fixed.
2181 * "-async" and "-noasync" options removed.
2183 Support for the broken "-noasync" option has been removed (it caused
2186 * New ``start'' command.
2188 This command runs the program until the begining of the main procedure.
2190 * New BSD Kernel Data Access Library (libkvm) interface
2192 Using ``target kvm'' it is now possible to debug kernel core dumps and
2193 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2194 platforms. Currently supported (native-only) configurations are:
2196 FreeBSD/amd64 x86_64-*-freebsd*
2197 FreeBSD/i386 i?86-*-freebsd*
2198 NetBSD/i386 i?86-*-netbsd*
2199 NetBSD/m68k m68*-*-netbsd*
2200 NetBSD/sparc sparc-*-netbsd*
2201 OpenBSD/amd64 x86_64-*-openbsd*
2202 OpenBSD/i386 i?86-*-openbsd*
2203 OpenBSD/m68k m68*-openbsd*
2204 OpenBSD/sparc sparc-*-openbsd*
2206 * Signal trampoline code overhauled
2208 Many generic problems with GDB's signal handling code have been fixed.
2209 These include: backtraces through non-contiguous stacks; recognition
2210 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2211 call; backtrace through a signal trampoline; step into and out of
2212 signal handlers; and single-stepping in the signal trampoline.
2214 Please note that kernel bugs are a limiting factor here. These
2215 features have been shown to work on an s390 GNU/Linux system that
2216 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2218 * Cygwin support for DWARF 2 added.
2220 * New native configurations
2222 GNU/Linux/hppa hppa*-*-linux*
2223 OpenBSD/hppa hppa*-*-openbsd*
2224 OpenBSD/m68k m68*-*-openbsd*
2225 OpenBSD/m88k m88*-*-openbsd*
2226 OpenBSD/powerpc powerpc-*-openbsd*
2227 NetBSD/vax vax-*-netbsd*
2228 OpenBSD/vax vax-*-openbsd*
2230 * END-OF-LIFE frame compatibility module
2232 GDB's internal frame infrastructure has been completely rewritten.
2233 The new infrastructure making it possible to support key new features
2234 including DWARF 2 Call Frame Information. To aid in the task of
2235 migrating old configurations to this new infrastructure, a
2236 compatibility module, that allowed old configurations to continue to
2237 work, was also included.
2239 GDB 6.2 will be the last release to include this frame compatibility
2240 module. This change directly impacts the following configurations:
2250 Unless there is activity to revive these configurations, they will be
2251 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2253 * REMOVED configurations and files
2255 Sun 3, running SunOS 3 m68*-*-sunos3*
2256 Sun 3, running SunOS 4 m68*-*-sunos4*
2257 Sun 2, running SunOS 3 m68000-*-sunos3*
2258 Sun 2, running SunOS 4 m68000-*-sunos4*
2259 Motorola 680x0 running LynxOS m68*-*-lynxos*
2260 AT&T 3b1/Unix pc m68*-att-*
2261 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2262 decstation mips-dec-* mips-little-*
2263 riscos mips-*-riscos* mips-*-sysv*
2264 sonymips mips-sony-*
2265 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2267 *** Changes in GDB 6.1.1:
2269 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2271 The TUI (Text-mode User Interface) is now built as part of a default
2272 GDB configuration. It is enabled by either selecting the TUI with the
2273 command line option "-i=tui" or by running the separate "gdbtui"
2274 program. For more information on the TUI, see the manual "Debugging
2277 * Pending breakpoint support (also included in GDB 6.1)
2279 Support has been added to allow you to specify breakpoints in shared
2280 libraries that have not yet been loaded. If a breakpoint location
2281 cannot be found, and the "breakpoint pending" option is set to auto,
2282 GDB queries you if you wish to make the breakpoint pending on a future
2283 shared-library load. If and when GDB resolves the breakpoint symbol,
2284 the pending breakpoint is removed as one or more regular breakpoints
2287 Pending breakpoints are very useful for GCJ Java debugging.
2289 * Fixed ISO-C build problems
2291 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2292 non ISO-C code that stopped them being built using a more strict ISO-C
2293 compiler (e.g., IBM's C compiler).
2295 * Fixed build problem on IRIX 5
2297 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2298 wasn't able to compile compile on an IRIX 5 system.
2300 * Added execute permission to gdb/gdbserver/configure
2302 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2303 permission. This bug would cause configure to fail on a number of
2304 systems (Solaris, IRIX). Ref: server/519.
2306 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2308 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2309 has been updated to use constant array sizes.
2311 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2313 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2314 its generated DWARF Call Frame Info. This encoding was causing GDB to
2315 panic, that panic has been fixed. Ref: gdb/1628.
2317 * Fixed a problem when examining parameters in shared library code.
2319 When examining parameters in optimized shared library code generated
2320 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2321 not available''. GDB now correctly displays the variable's value.
2323 *** Changes in GDB 6.1:
2325 * Removed --with-mmalloc
2327 Support for the mmalloc memory manager has been removed, as it
2328 conflicted with the internal gdb byte cache.
2330 * Changes in AMD64 configurations
2332 The AMD64 target now includes the %cs and %ss registers. As a result
2333 the AMD64 remote protocol has changed; this affects the floating-point
2334 and SSE registers. If you rely on those registers for your debugging,
2335 you should upgrade gdbserver on the remote side.
2337 * Revised SPARC target
2339 The SPARC target has been completely revised, incorporating the
2340 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2341 support for LynxOS and SunOS 4 has been dropped. Calling functions
2342 from within GDB on operating systems with a non-executable stack
2343 (Solaris, OpenBSD) now works.
2347 GDB has a new C++ demangler which does a better job on the mangled
2348 names generated by current versions of g++. It also runs faster, so
2349 with this and other changes gdb should now start faster on large C++
2352 * DWARF 2 Location Expressions
2354 GDB support for location expressions has been extended to support function
2355 arguments and frame bases. Older versions of GDB could crash when they
2358 * C++ nested types and namespaces
2360 GDB's support for nested types and namespaces in C++ has been
2361 improved, especially if you use the DWARF 2 debugging format. (This
2362 is the default for recent versions of GCC on most platforms.)
2363 Specifically, if you have a class "Inner" defined within a class or
2364 namespace "Outer", then GDB realizes that the class's name is
2365 "Outer::Inner", not simply "Inner". This should greatly reduce the
2366 frequency of complaints about not finding RTTI symbols. In addition,
2367 if you are stopped at inside of a function defined within a namespace,
2368 GDB modifies its name lookup accordingly.
2370 * New native configurations
2372 NetBSD/amd64 x86_64-*-netbsd*
2373 OpenBSD/amd64 x86_64-*-openbsd*
2374 OpenBSD/alpha alpha*-*-openbsd*
2375 OpenBSD/sparc sparc-*-openbsd*
2376 OpenBSD/sparc64 sparc64-*-openbsd*
2378 * New debugging protocols
2380 M32R with SDI protocol m32r-*-elf*
2382 * "set prompt-escape-char" command deleted.
2384 The command "set prompt-escape-char" has been deleted. This command,
2385 and its very obscure effet on GDB's prompt, was never documented,
2386 tested, nor mentioned in the NEWS file.
2388 * OBSOLETE configurations and files
2390 Configurations that have been declared obsolete in this release have
2391 been commented out. Unless there is activity to revive these
2392 configurations, the next release of GDB will have their sources
2393 permanently REMOVED.
2395 Sun 3, running SunOS 3 m68*-*-sunos3*
2396 Sun 3, running SunOS 4 m68*-*-sunos4*
2397 Sun 2, running SunOS 3 m68000-*-sunos3*
2398 Sun 2, running SunOS 4 m68000-*-sunos4*
2399 Motorola 680x0 running LynxOS m68*-*-lynxos*
2400 AT&T 3b1/Unix pc m68*-att-*
2401 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2402 decstation mips-dec-* mips-little-*
2403 riscos mips-*-riscos* mips-*-sysv*
2404 sonymips mips-sony-*
2405 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2407 * REMOVED configurations and files
2409 SGI Irix-4.x mips-sgi-irix4 or iris4
2410 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2411 Z8000 simulator z8k-zilog-none or z8ksim
2412 Matsushita MN10200 w/simulator mn10200-*-*
2413 H8/500 simulator h8500-hitachi-hms or h8500hms
2414 HP/PA running BSD hppa*-*-bsd*
2415 HP/PA running OSF/1 hppa*-*-osf*
2416 HP/PA Pro target hppa*-*-pro*
2417 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2418 386BSD i[3456]86-*-bsd*
2419 Sequent family i[3456]86-sequent-sysv4*
2420 i[3456]86-sequent-sysv*
2421 i[3456]86-sequent-bsd*
2422 SPARC running LynxOS sparc-*-lynxos*
2423 SPARC running SunOS 4 sparc-*-sunos4*
2424 Tsqware Sparclet sparclet-*-*
2425 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2427 *** Changes in GDB 6.0:
2431 Support for debugging the Objective-C programming language has been
2432 integrated into GDB.
2434 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2436 DWARF 2's Call Frame Information makes available compiler generated
2437 information that more exactly describes the program's run-time stack.
2438 By using this information, GDB is able to provide more robust stack
2441 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2442 have been updated to use a new backtrace mechanism which includes
2443 DWARF 2 CFI support.
2447 GDB's remote protocol has been extended to include support for hosted
2448 file I/O (where the remote target uses GDB's file system). See GDB's
2449 remote protocol documentation for details.
2451 * All targets using the new architecture framework.
2453 All of GDB's targets have been updated to use the new internal
2454 architecture framework. The way is now open for future GDB releases
2455 to include cross-architecture native debugging support (i386 on amd64,
2458 * GNU/Linux's Thread Local Storage (TLS)
2460 GDB now includes support for for the GNU/Linux implementation of
2461 per-thread variables.
2463 * GNU/Linux's Native POSIX Thread Library (NPTL)
2465 GDB's thread code has been updated to work with either the new
2466 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2468 * Separate debug info.
2470 GDB, in conjunction with BINUTILS, now supports a mechanism for
2471 automatically loading debug information from a separate file. Instead
2472 of shipping full debug and non-debug versions of system libraries,
2473 system integrators can now instead ship just the stripped libraries
2474 and optional debug files.
2476 * DWARF 2 Location Expressions
2478 DWARF 2 Location Expressions allow the compiler to more completely
2479 describe the location of variables (even in optimized code) to the
2482 GDB now includes preliminary support for location expressions (support
2483 for DW_OP_piece is still missing).
2487 A number of long standing bugs that caused GDB to die while starting a
2488 Java application have been fixed. GDB's Java support is now
2489 considered "useable".
2491 * GNU/Linux support for fork, vfork, and exec.
2493 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2494 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2497 * GDB supports logging output to a file
2499 There are two new commands, "set logging" and "show logging", which can be
2500 used to capture GDB's output to a file.
2502 * The meaning of "detach" has changed for gdbserver
2504 The "detach" command will now resume the application, as documented. To
2505 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2508 * d10v, m68hc11 `regs' command deprecated
2510 The `info registers' command has been updated so that it displays the
2511 registers using a format identical to the old `regs' command.
2515 A new command, "maint set profile on/off", has been added. This command can
2516 be used to enable or disable profiling while running GDB, to profile a
2517 session or a set of commands. In addition there is a new configure switch,
2518 "--enable-profiling", which will cause GDB to be compiled with profiling
2519 data, for more informative profiling results.
2521 * Default MI syntax changed to "mi2".
2523 The default MI (machine interface) syntax, enabled by the command line
2524 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2525 "mi1", can be enabled by specifying the option "-i=mi1".
2527 Support for the original "mi0" syntax (included in GDB 5.0) has been
2530 Fix for gdb/192: removed extraneous space when displaying frame level.
2531 Fix for gdb/672: update changelist is now output in mi list format.
2532 Fix for gdb/702: a -var-assign that updates the value now shows up
2533 in a subsequent -var-update.
2535 * New native configurations.
2537 FreeBSD/amd64 x86_64-*-freebsd*
2539 * Multi-arched targets.
2541 HP/PA HPUX11 hppa*-*-hpux*
2542 Renesas M32R/D w/simulator m32r-*-elf*
2544 * OBSOLETE configurations and files
2546 Configurations that have been declared obsolete in this release have
2547 been commented out. Unless there is activity to revive these
2548 configurations, the next release of GDB will have their sources
2549 permanently REMOVED.
2551 Z8000 simulator z8k-zilog-none or z8ksim
2552 Matsushita MN10200 w/simulator mn10200-*-*
2553 H8/500 simulator h8500-hitachi-hms or h8500hms
2554 HP/PA running BSD hppa*-*-bsd*
2555 HP/PA running OSF/1 hppa*-*-osf*
2556 HP/PA Pro target hppa*-*-pro*
2557 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2558 Sequent family i[3456]86-sequent-sysv4*
2559 i[3456]86-sequent-sysv*
2560 i[3456]86-sequent-bsd*
2561 Tsqware Sparclet sparclet-*-*
2562 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2564 * REMOVED configurations and files
2567 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2568 IBM AIX PS/2 i[3456]86-*-aix
2569 i386 running Mach 3.0 i[3456]86-*-mach3*
2570 i386 running Mach i[3456]86-*-mach*
2571 i386 running OSF/1 i[3456]86-*osf1mk*
2572 HP/Apollo 68k Family m68*-apollo*-sysv*,
2574 m68*-hp-bsd*, m68*-hp-hpux*
2575 Argonaut Risc Chip (ARC) arc-*-*
2576 Mitsubishi D30V d30v-*-*
2577 Fujitsu FR30 fr30-*-elf*
2578 OS/9000 i[34]86-*-os9k
2579 I960 with MON960 i960-*-coff
2581 * MIPS $fp behavior changed
2583 The convenience variable $fp, for the MIPS, now consistently returns
2584 the address of the current frame's base. Previously, depending on the
2585 context, $fp could refer to either $sp or the current frame's base
2586 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2587 The GNU Source-Level Debugger''.
2589 *** Changes in GDB 5.3:
2591 * GNU/Linux shared library multi-threaded performance improved.
2593 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2594 `/proc', in preference to `ptrace' for memory reads. This may result
2595 in an improvement in the start-up time of multi-threaded, shared
2596 library applications when run under GDB. One GDB user writes: ``loads
2597 shared libs like mad''.
2599 * ``gdbserver'' now supports multi-threaded applications on some targets
2601 Support for debugging multi-threaded applications which use
2602 the GNU/Linux LinuxThreads package has been added for
2603 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2604 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2606 * GDB now supports C/C++ preprocessor macros.
2608 GDB now expands preprocessor macro invocations in C/C++ expressions,
2609 and provides various commands for showing macro definitions and how
2612 The new command `macro expand EXPRESSION' expands any macro
2613 invocations in expression, and shows the result.
2615 The new command `show macro MACRO-NAME' shows the definition of the
2616 macro named MACRO-NAME, and where it was defined.
2618 Most compilers don't include information about macros in the debugging
2619 information by default. In GCC 3.1, for example, you need to compile
2620 your program with the options `-gdwarf-2 -g3'. If the macro
2621 information is present in the executable, GDB will read it.
2623 * Multi-arched targets.
2625 DEC Alpha (partial) alpha*-*-*
2626 DEC VAX (partial) vax-*-*
2628 National Semiconductor NS32000 (partial) ns32k-*-*
2629 Motorola 68000 (partial) m68k-*-*
2630 Motorola MCORE mcore-*-*
2634 Fujitsu FRV architecture added by Red Hat frv*-*-*
2637 * New native configurations
2639 Alpha NetBSD alpha*-*-netbsd*
2640 SH NetBSD sh*-*-netbsdelf*
2641 MIPS NetBSD mips*-*-netbsd*
2642 UltraSPARC NetBSD sparc64-*-netbsd*
2644 * OBSOLETE configurations and files
2646 Configurations that have been declared obsolete in this release have
2647 been commented out. Unless there is activity to revive these
2648 configurations, the next release of GDB will have their sources
2649 permanently REMOVED.
2651 Mitsubishi D30V d30v-*-*
2652 OS/9000 i[34]86-*-os9k
2653 IBM AIX PS/2 i[3456]86-*-aix
2654 Fujitsu FR30 fr30-*-elf*
2655 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2656 Argonaut Risc Chip (ARC) arc-*-*
2657 i386 running Mach 3.0 i[3456]86-*-mach3*
2658 i386 running Mach i[3456]86-*-mach*
2659 i386 running OSF/1 i[3456]86-*osf1mk*
2660 HP/Apollo 68k Family m68*-apollo*-sysv*,
2662 m68*-hp-bsd*, m68*-hp-hpux*
2663 I960 with MON960 i960-*-coff
2665 * OBSOLETE languages
2667 CHILL, a Pascal like language used by telecommunications companies.
2669 * REMOVED configurations and files
2671 AMD 29k family via UDI a29k-amd-udi, udi29k
2672 A29K VxWorks a29k-*-vxworks
2673 AMD 29000 embedded, using EBMON a29k-none-none
2674 AMD 29000 embedded with COFF a29k-none-coff
2675 AMD 29000 embedded with a.out a29k-none-aout
2677 testsuite/gdb.hp/gdb.threads-hp/ directory
2679 * New command "set max-user-call-depth <nnn>"
2681 This command allows the user to limit the call depth of user-defined
2682 commands. The default is 1024.
2684 * Changes in FreeBSD/i386 native debugging.
2686 Support for the "generate-core-file" has been added.
2688 * New commands "dump", "append", and "restore".
2690 These commands allow data to be copied from target memory
2691 to a bfd-format or binary file (dump and append), and back
2692 from a file into memory (restore).
2694 * Improved "next/step" support on multi-processor Alpha Tru64.
2696 The previous single-step mechanism could cause unpredictable problems,
2697 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2698 of a software single-step mechanism prevents this.
2700 *** Changes in GDB 5.2.1:
2708 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2709 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2710 Fix, by Joel Brobecker imported from mainline.
2712 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2713 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2714 Fix, by Fred Fish, imported from mainline.
2716 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2717 Surprisingly enough, it works now.
2718 By Michal Ludvig, imported from mainline.
2720 i386 hardware watchpoint support:
2721 avoid misses on second run for some targets.
2722 By Pierre Muller, imported from mainline.
2724 *** Changes in GDB 5.2:
2726 * New command "set trust-readonly-sections on[off]".
2728 This command is a hint that tells gdb that read-only sections
2729 really are read-only (ie. that their contents will not change).
2730 In this mode, gdb will go to the object file rather than the
2731 target to read memory from read-only sections (such as ".text").
2732 This can be a significant performance improvement on some
2733 (notably embedded) targets.
2735 * New command "generate-core-file" (or "gcore").
2737 This new gdb command allows the user to drop a core file of the child
2738 process state at any time. So far it's been implemented only for
2739 GNU/Linux and Solaris, but should be relatively easily ported to other
2740 hosts. Argument is core file name (defaults to core.<pid>).
2742 * New command line option
2744 GDB now accepts --pid or -p followed by a process id.
2746 * Change in command line behavior -- corefiles vs. process ids.
2748 There is a subtle behavior in the way in which GDB handles
2749 command line arguments. The first non-flag argument is always
2750 a program to debug, but the second non-flag argument may either
2751 be a corefile or a process id. Previously, GDB would attempt to
2752 open the second argument as a corefile, and if that failed, would
2753 issue a superfluous error message and then attempt to attach it as
2754 a process. Now, if the second argument begins with a non-digit,
2755 it will be treated as a corefile. If it begins with a digit,
2756 GDB will attempt to attach it as a process, and if no such process
2757 is found, will then attempt to open it as a corefile.
2759 * Changes in ARM configurations.
2761 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2762 configuration is fully multi-arch.
2764 * New native configurations
2766 ARM NetBSD arm*-*-netbsd*
2767 x86 OpenBSD i[3456]86-*-openbsd*
2768 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2769 Sparc64 running FreeBSD sparc64-*-freebsd*
2773 Sanyo XStormy16 xstormy16-elf
2775 * OBSOLETE configurations and files
2777 Configurations that have been declared obsolete in this release have
2778 been commented out. Unless there is activity to revive these
2779 configurations, the next release of GDB will have their sources
2780 permanently REMOVED.
2782 AMD 29k family via UDI a29k-amd-udi, udi29k
2783 A29K VxWorks a29k-*-vxworks
2784 AMD 29000 embedded, using EBMON a29k-none-none
2785 AMD 29000 embedded with COFF a29k-none-coff
2786 AMD 29000 embedded with a.out a29k-none-aout
2788 testsuite/gdb.hp/gdb.threads-hp/ directory
2790 * REMOVED configurations and files
2792 TI TMS320C80 tic80-*-*
2794 PowerPC Solaris powerpcle-*-solaris*
2795 PowerPC Windows NT powerpcle-*-cygwin32
2796 PowerPC Netware powerpc-*-netware*
2797 Harris/CXUX m88k m88*-harris-cxux*
2798 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2799 ns32k-utek-sysv* ns32k-utek-*
2800 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2801 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2802 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2803 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2804 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2806 * Changes to command line processing
2808 The new `--args' feature can be used to specify command-line arguments
2809 for the inferior from gdb's command line.
2811 * Changes to key bindings
2813 There is a new `operate-and-get-next' function bound to `C-o'.
2815 *** Changes in GDB 5.1.1
2817 Fix compile problem on DJGPP.
2819 Fix a problem with floating-point registers on the i386 being
2822 Fix to stop GDB crashing on .debug_str debug info.
2824 Numerous documentation fixes.
2826 Numerous testsuite fixes.
2828 *** Changes in GDB 5.1:
2830 * New native configurations
2832 Alpha FreeBSD alpha*-*-freebsd*
2833 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2834 MIPS GNU/Linux mips*-*-linux*
2835 MIPS SGI Irix 6.x mips*-sgi-irix6*
2836 ia64 AIX ia64-*-aix*
2837 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2841 Motorola 68HC11 and 68HC12 m68hc11-elf
2843 UltraSparc running GNU/Linux sparc64-*-linux*
2845 * OBSOLETE configurations and files
2847 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2848 Harris/CXUX m88k m88*-harris-cxux*
2849 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2850 ns32k-utek-sysv* ns32k-utek-*
2851 TI TMS320C80 tic80-*-*
2853 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2854 PowerPC Solaris powerpcle-*-solaris*
2855 PowerPC Windows NT powerpcle-*-cygwin32
2856 PowerPC Netware powerpc-*-netware*
2857 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2858 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2859 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2860 Apple Macintosh (MPW) host N/A
2862 stuff.c (Program to stuff files into a specially prepared space in kdb)
2863 kdb-start.c (Main loop for the standalone kernel debugger)
2865 Configurations that have been declared obsolete in this release have
2866 been commented out. Unless there is activity to revive these
2867 configurations, the next release of GDB will have their sources
2868 permanently REMOVED.
2870 * REMOVED configurations and files
2872 Altos 3068 m68*-altos-*
2873 Convex c1-*-*, c2-*-*
2875 ARM RISCix arm-*-* (as host)
2879 * GDB has been converted to ISO C.
2881 GDB's source code has been converted to ISO C. In particular, the
2882 sources are fully protoized, and rely on standard headers being
2887 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2889 * The MI enabled by default.
2891 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2892 revised and enabled by default. Packages which use GDB as a debugging
2893 engine behind a UI or another front end are encouraged to switch to
2894 using the GDB/MI interface, instead of the old annotations interface
2895 which is now deprecated.
2897 * Support for debugging Pascal programs.
2899 GDB now includes support for debugging Pascal programs. The following
2900 main features are supported:
2902 - Pascal-specific data types such as sets;
2904 - automatic recognition of Pascal sources based on file-name
2907 - Pascal-style display of data types, variables, and functions;
2909 - a Pascal expression parser.
2911 However, some important features are not yet supported.
2913 - Pascal string operations are not supported at all;
2915 - there are some problems with boolean types;
2917 - Pascal type hexadecimal constants are not supported
2918 because they conflict with the internal variables format;
2920 - support for Pascal objects and classes is not full yet;
2922 - unlike Pascal, GDB is case-sensitive for symbol names.
2924 * Changes in completion.
2926 Commands such as `shell', `run' and `set args', which pass arguments
2927 to inferior programs, now complete on file names, similar to what
2928 users expect at the shell prompt.
2930 Commands which accept locations, such as `disassemble', `print',
2931 `breakpoint', `until', etc. now complete on filenames as well as
2932 program symbols. Thus, if you type "break foob TAB", and the source
2933 files linked into the programs include `foobar.c', that file name will
2934 be one of the candidates for completion. However, file names are not
2935 considered for completion after you typed a colon that delimits a file
2936 name from a name of a function in that file, as in "break foo.c:bar".
2938 `set demangle-style' completes on available demangling styles.
2940 * New platform-independent commands:
2942 It is now possible to define a post-hook for a command as well as a
2943 hook that runs before the command. For more details, see the
2944 documentation of `hookpost' in the GDB manual.
2946 * Changes in GNU/Linux native debugging.
2948 Support for debugging multi-threaded programs has been completely
2949 revised for all platforms except m68k and sparc. You can now debug as
2950 many threads as your system allows you to have.
2952 Attach/detach is supported for multi-threaded programs.
2954 Support for SSE registers was added for x86. This doesn't work for
2955 multi-threaded programs though.
2957 * Changes in MIPS configurations.
2959 Multi-arch support is enabled for all MIPS configurations.
2961 GDB can now be built as native debugger on SGI Irix 6.x systems for
2962 debugging n32 executables. (Debugging 64-bit executables is not yet
2965 * Unified support for hardware watchpoints in all x86 configurations.
2967 Most (if not all) native x86 configurations support hardware-assisted
2968 breakpoints and watchpoints in a unified manner. This support
2969 implements debug register sharing between watchpoints, which allows to
2970 put a virtually infinite number of watchpoints on the same address,
2971 and also supports watching regions up to 16 bytes with several debug
2974 The new maintenance command `maintenance show-debug-regs' toggles
2975 debugging print-outs in functions that insert, remove, and test
2976 watchpoints and hardware breakpoints.
2978 * Changes in the DJGPP native configuration.
2980 New command ``info dos sysinfo'' displays assorted information about
2981 the CPU, OS, memory, and DPMI server.
2983 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2984 display information about segment descriptors stored in GDT, LDT, and
2987 New commands ``info dos pde'' and ``info dos pte'' display entries
2988 from Page Directory and Page Tables (for now works with CWSDPMI only).
2989 New command ``info dos address-pte'' displays the Page Table entry for
2990 a given linear address.
2992 GDB can now pass command lines longer than 126 characters to the
2993 program being debugged (requires an update to the libdbg.a library
2994 which is part of the DJGPP development kit).
2996 DWARF2 debug info is now supported.
2998 It is now possible to `step' and `next' through calls to `longjmp'.
3000 * Changes in documentation.
3002 All GDB documentation was converted to GFDL, the GNU Free
3003 Documentation License.
3005 Tracepoints-related commands are now fully documented in the GDB
3008 TUI, the Text-mode User Interface, is now documented in the manual.
3010 Tracepoints-related commands are now fully documented in the GDB
3013 The "GDB Internals" manual now has an index. It also includes
3014 documentation of `ui_out' functions, GDB coding standards, x86
3015 hardware watchpoints, and memory region attributes.
3017 * GDB's version number moved to ``version.in''
3019 The Makefile variable VERSION has been replaced by the file
3020 ``version.in''. People creating GDB distributions should update the
3021 contents of this file.
3025 GUD support is now a standard part of the EMACS distribution.
3027 *** Changes in GDB 5.0:
3029 * Improved support for debugging FP programs on x86 targets
3031 Unified and much-improved support for debugging floating-point
3032 programs on all x86 targets. In particular, ``info float'' now
3033 displays the FP registers in the same format on all x86 targets, with
3034 greater level of detail.
3036 * Improvements and bugfixes in hardware-assisted watchpoints
3038 It is now possible to watch array elements, struct members, and
3039 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3040 on x86 targets no longer erroneously trigger when the address is
3043 * Improvements in the native DJGPP version of GDB
3045 The distribution now includes all the scripts and auxiliary files
3046 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3047 machines ``out of the box''.
3049 The DJGPP version can now debug programs that use signals. It is
3050 possible to catch signals that happened in the debuggee, deliver
3051 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3052 would kill the program being debugged.) Programs that hook hardware
3053 interrupts (keyboard, timer, etc.) can also be debugged.
3055 It is now possible to debug DJGPP programs that redirect their
3056 standard handles or switch them to raw (as opposed to cooked) mode, or
3057 even close them. The command ``run < foo > bar'' works as expected,
3058 and ``info terminal'' reports useful information about the debuggee's
3059 terminal, including raw/cooked mode, redirection, etc.
3061 The DJGPP version now uses termios functions for console I/O, which
3062 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3065 DOS-style file names with drive letters are now fully supported by
3068 It is now possible to debug DJGPP programs that switch their working
3069 directory. It is also possible to rerun the debuggee any number of
3070 times without restarting GDB; thus, you can use the same setup,
3071 breakpoints, etc. for many debugging sessions.
3073 * New native configurations
3075 ARM GNU/Linux arm*-*-linux*
3076 PowerPC GNU/Linux powerpc-*-linux*
3080 Motorola MCore mcore-*-*
3081 x86 VxWorks i[3456]86-*-vxworks*
3082 PowerPC VxWorks powerpc-*-vxworks*
3083 TI TMS320C80 tic80-*-*
3085 * OBSOLETE configurations
3087 Altos 3068 m68*-altos-*
3088 Convex c1-*-*, c2-*-*
3090 ARM RISCix arm-*-* (as host)
3093 Configurations that have been declared obsolete will be commented out,
3094 but the code will be left in place. If there is no activity to revive
3095 these configurations before the next release of GDB, the sources will
3096 be permanently REMOVED.
3098 * Gould support removed
3100 Support for the Gould PowerNode and NP1 has been removed.
3102 * New features for SVR4
3104 On SVR4 native platforms (such as Solaris), if you attach to a process
3105 without first loading a symbol file, GDB will now attempt to locate and
3106 load symbols from the running process's executable file.
3108 * Many C++ enhancements
3110 C++ support has been greatly improved. Overload resolution now works properly
3111 in almost all cases. RTTI support is on the way.
3113 * Remote targets can connect to a sub-program
3115 A popen(3) style serial-device has been added. This device starts a
3116 sub-process (such as a stand-alone simulator) and then communicates
3117 with that. The sub-program to run is specified using the syntax
3118 ``|<program> <args>'' vis:
3120 (gdb) set remotedebug 1
3121 (gdb) target extended-remote |mn10300-elf-sim program-args
3123 * MIPS 64 remote protocol
3125 A long standing bug in the mips64 remote protocol where by GDB
3126 expected certain 32 bit registers (ex SR) to be transfered as 32
3127 instead of 64 bits has been fixed.
3129 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3130 added to provide backward compatibility with older versions of GDB.
3132 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3134 The command ``set remotebinarydownload'' command has been replaced by
3135 ``set remote X-packet''. Other commands in ``set remote'' family
3136 include ``set remote P-packet''.
3138 * Breakpoint commands accept ranges.
3140 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3141 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3142 ``tracepoint passcount'' also accepts a range of tracepoints.
3144 * ``apropos'' command added.
3146 The ``apropos'' command searches through command names and
3147 documentation strings, printing out matches, making it much easier to
3148 try to find a command that does what you are looking for.
3152 A new machine oriented interface (MI) has been added to GDB. This
3153 interface is designed for debug environments running GDB as a separate
3154 process. This is part of the long term libGDB project. See the
3155 "GDB/MI" chapter of the GDB manual for further information. It can be
3156 enabled by configuring with:
3158 .../configure --enable-gdbmi
3160 *** Changes in GDB-4.18:
3162 * New native configurations
3164 HP-UX 10.20 hppa*-*-hpux10.20
3165 HP-UX 11.x hppa*-*-hpux11.0*
3166 M68K GNU/Linux m68*-*-linux*
3170 Fujitsu FR30 fr30-*-elf*
3171 Intel StrongARM strongarm-*-*
3172 Mitsubishi D30V d30v-*-*
3174 * OBSOLETE configurations
3176 Gould PowerNode, NP1 np1-*-*, pn-*-*
3178 Configurations that have been declared obsolete will be commented out,
3179 but the code will be left in place. If there is no activity to revive
3180 these configurations before the next release of GDB, the sources will
3181 be permanently REMOVED.
3185 As a compatibility experiment, GDB's source files buildsym.h and
3186 buildsym.c have been converted to pure standard C, no longer
3187 containing any K&R compatibility code. We believe that all systems in
3188 use today either come with a standard C compiler, or have a GCC port
3189 available. If this is not true, please report the affected
3190 configuration to bug-gdb@gnu.org immediately. See the README file for
3191 information about getting a standard C compiler if you don't have one
3196 GDB now uses readline 2.2.
3198 * set extension-language
3200 You can now control the mapping between filename extensions and source
3201 languages by using the `set extension-language' command. For instance,
3202 you can ask GDB to treat .c files as C++ by saying
3203 set extension-language .c c++
3204 The command `info extensions' lists all of the recognized extensions
3205 and their associated languages.
3207 * Setting processor type for PowerPC and RS/6000
3209 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3210 you can use the `set processor' command to specify what variant of the
3211 PowerPC family you are debugging. The command
3215 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3216 following PowerPC and RS6000 variants:
3218 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3219 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3221 403GC IBM PowerPC 403GC
3222 505 Motorola PowerPC 505
3223 860 Motorola PowerPC 860 or 850
3224 601 Motorola PowerPC 601
3225 602 Motorola PowerPC 602
3226 603 Motorola/IBM PowerPC 603 or 603e
3227 604 Motorola PowerPC 604 or 604e
3228 750 Motorola/IBM PowerPC 750 or 750
3230 At the moment, this command just tells GDB what to name the
3231 special-purpose processor registers. Since almost all the affected
3232 registers are inaccessible to user-level programs, this command is
3233 only useful for remote debugging in its present form.
3237 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3238 more extensive support for HP-UX. Added features include shared
3239 library support, kernel threads and hardware watchpoints for 11.00,
3240 support for HP's ANSI C and C++ compilers, and a compatibility mode
3241 for xdb and dbx commands.
3245 HP's donation includes the new concept of catchpoints, which is a
3246 generalization of the old catch command. On HP-UX, it is now possible
3247 to catch exec, fork, and vfork, as well as library loading.
3249 This means that the existing catch command has changed; its first
3250 argument now specifies the type of catch to be set up. See the
3251 output of "help catch" for a list of catchpoint types.
3253 * Debugging across forks
3255 On HP-UX, you can choose which process to debug when a fork() happens
3260 HP has donated a curses-based terminal user interface (TUI). To get
3261 it, build with --enable-tui. Although this can be enabled for any
3262 configuration, at present it only works for native HP debugging.
3264 * GDB remote protocol additions
3266 A new protocol packet 'X' that writes binary data is now available.
3267 Default behavior is to try 'X', then drop back to 'M' if the stub
3268 fails to respond. The settable variable `remotebinarydownload'
3269 allows explicit control over the use of 'X'.
3271 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3272 full 64-bit address. The command
3274 set remoteaddresssize 32
3276 can be used to revert to the old behaviour. For existing remote stubs
3277 the change should not be noticed, as the additional address information
3280 In order to assist in debugging stubs, you may use the maintenance
3281 command `packet' to send any text string to the stub. For instance,
3283 maint packet heythere
3285 sends the packet "$heythere#<checksum>". Note that it is very easy to
3286 disrupt a debugging session by sending the wrong packet at the wrong
3289 The compare-sections command allows you to compare section data on the
3290 target to what is in the executable file without uploading or
3291 downloading, by comparing CRC checksums.
3293 * Tracing can collect general expressions
3295 You may now collect general expressions at tracepoints. This requires
3296 further additions to the target-side stub; see tracepoint.c and
3297 doc/agentexpr.texi for further details.
3299 * mask-address variable for Mips
3301 For Mips targets, you may control the zeroing of the upper 32 bits of
3302 a 64-bit address by entering `set mask-address on'. This is mainly
3303 of interest to users of embedded R4xxx and R5xxx processors.
3305 * Higher serial baud rates
3307 GDB's serial code now allows you to specify baud rates 57600, 115200,
3308 230400, and 460800 baud. (Note that your host system may not be able
3309 to achieve all of these rates.)
3313 The i960 configuration now includes an initial implementation of a
3314 builtin simulator, contributed by Jim Wilson.
3317 *** Changes in GDB-4.17:
3319 * New native configurations
3321 Alpha GNU/Linux alpha*-*-linux*
3322 Unixware 2.x i[3456]86-unixware2*
3323 Irix 6.x mips*-sgi-irix6*
3324 PowerPC GNU/Linux powerpc-*-linux*
3325 PowerPC Solaris powerpcle-*-solaris*
3326 Sparc GNU/Linux sparc-*-linux*
3327 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3331 Argonaut Risc Chip (ARC) arc-*-*
3332 Hitachi H8/300S h8300*-*-*
3333 Matsushita MN10200 w/simulator mn10200-*-*
3334 Matsushita MN10300 w/simulator mn10300-*-*
3335 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3336 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3337 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3338 Mitsubishi D10V w/simulator d10v-*-*
3339 Mitsubishi M32R/D w/simulator m32r-*-elf*
3340 Tsqware Sparclet sparclet-*-*
3341 NEC V850 w/simulator v850-*-*
3343 * New debugging protocols
3345 ARM with RDI protocol arm*-*-*
3346 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3347 DDB and LSI variants of PMON protocol mips*-*-*
3348 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3349 PowerPC with SDS protocol powerpc{,le}-*-eabi
3350 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3354 All configurations can now understand and use the DWARF 2 debugging
3355 format. The choice is automatic, if the symbol file contains DWARF 2
3360 GDB now includes basic Java language support. This support is
3361 only useful with Java compilers that produce native machine code.
3363 * solib-absolute-prefix and solib-search-path
3365 For SunOS and SVR4 shared libraries, you may now set the prefix for
3366 loading absolute shared library symbol files, and the search path for
3367 locating non-absolute shared library symbol files.
3369 * Live range splitting
3371 GDB can now effectively debug code for which GCC has performed live
3372 range splitting as part of its optimization. See gdb/doc/LRS for
3373 more details on the expected format of the stabs information.
3377 GDB's support for the GNU Hurd, including thread debugging, has been
3378 updated to work with current versions of the Hurd.
3382 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3383 instruction set. ARM GDB automatically detects when Thumb
3384 instructions are in use, and adjusts disassembly and backtracing
3389 GDB's MIPS target configurations now handle the MIP16 16-bit
3394 GDB now includes support for overlays; if an executable has been
3395 linked such that multiple sections are based at the same address, GDB
3396 will decide which section to use for symbolic info. You can choose to
3397 control the decision manually, using overlay commands, or implement
3398 additional target-side support and use "overlay load-target" to bring
3399 in the overlay mapping. Do "help overlay" for more detail.
3403 The command "info symbol <address>" displays information about
3404 the symbol at the specified address.
3408 The standard remote protocol now includes an extension that allows
3409 asynchronous collection and display of trace data. This requires
3410 extensive support in the target-side debugging stub. Tracing mode
3411 includes a new interaction mode in GDB and new commands: see the
3412 file tracepoint.c for more details.
3416 Configurations for embedded MIPS now include a simulator contributed
3417 by Cygnus Solutions. The simulator supports the instruction sets
3418 of most MIPS variants.
3422 Sparc configurations may now include the ERC32 simulator contributed
3423 by the European Space Agency. The simulator is not built into
3424 Sparc targets by default; configure with --enable-sim to include it.
3428 For target configurations that may include multiple variants of a
3429 basic architecture (such as MIPS and SH), you may now set the
3430 architecture explicitly. "set arch" sets, "info arch" lists
3431 the possible architectures.
3433 *** Changes in GDB-4.16:
3435 * New native configurations
3437 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3438 M68K NetBSD m68k-*-netbsd*
3439 PowerPC AIX 4.x powerpc-*-aix*
3440 PowerPC MacOS powerpc-*-macos*
3441 PowerPC Windows NT powerpcle-*-cygwin32
3442 RS/6000 AIX 4.x rs6000-*-aix4*
3446 ARM with RDP protocol arm-*-*
3447 I960 with MON960 i960-*-coff
3448 MIPS VxWorks mips*-*-vxworks*
3449 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3450 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3452 Matra Sparclet sparclet-*-*
3456 The powerpc-eabi configuration now includes the PSIM simulator,
3457 contributed by Andrew Cagney, with assistance from Mike Meissner.
3458 PSIM is a very elaborate model of the PowerPC, including not only
3459 basic instruction set execution, but also details of execution unit
3460 performance and I/O hardware. See sim/ppc/README for more details.
3464 GDB now works with Solaris 2.5.
3466 * Windows 95/NT native
3468 GDB will now work as a native debugger on Windows 95 and Windows NT.
3469 To build it from source, you must use the "gnu-win32" environment,
3470 which uses a DLL to emulate enough of Unix to run the GNU tools.
3471 Further information, binaries, and sources are available at
3472 ftp.cygnus.com, under pub/gnu-win32.
3474 * dont-repeat command
3476 If a user-defined command includes the command `dont-repeat', then the
3477 command will not be repeated if the user just types return. This is
3478 useful if the command is time-consuming to run, so that accidental
3479 extra keystrokes don't run the same command many times.
3481 * Send break instead of ^C
3483 The standard remote protocol now includes an option to send a break
3484 rather than a ^C to the target in order to interrupt it. By default,
3485 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3487 * Remote protocol timeout
3489 The standard remote protocol includes a new variable `remotetimeout'
3490 that allows you to set the number of seconds before GDB gives up trying
3491 to read from the target. The default value is 2.
3493 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3495 By default GDB will automatically keep track of objects as they are
3496 loaded and unloaded by the dynamic linker. By using the command `set
3497 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3498 when shared library events occur, thus allowing you to set breakpoints
3499 in shared libraries which are explicitly loaded by the inferior.
3501 Note this feature does not work on hpux8. On hpux9 you must link
3502 /usr/lib/end.o into your program. This feature should work
3503 automatically on hpux10.
3505 * Irix 5.x hardware watchpoint support
3507 Irix 5 configurations now support the use of hardware watchpoints.
3509 * Mips protocol "SYN garbage limit"
3511 When debugging a Mips target using the `target mips' protocol, you
3512 may set the number of characters that GDB will ignore by setting
3513 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3514 every character. The default value is 1050.
3516 * Recording and replaying remote debug sessions
3518 If you set `remotelogfile' to the name of a file, gdb will write to it
3519 a recording of a remote debug session. This recording may then be
3520 replayed back to gdb using "gdbreplay". See gdbserver/README for
3521 details. This is useful when you have a problem with GDB while doing
3522 remote debugging; you can make a recording of the session and send it
3523 to someone else, who can then recreate the problem.
3525 * Speedups for remote debugging
3527 GDB includes speedups for downloading and stepping MIPS systems using
3528 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3529 and more efficient S-record downloading.
3531 * Memory use reductions and statistics collection
3533 GDB now uses less memory and reports statistics about memory usage.
3534 Try the `maint print statistics' command, for example.
3536 *** Changes in GDB-4.15:
3538 * Psymtabs for XCOFF
3540 The symbol reader for AIX GDB now uses partial symbol tables. This
3541 can greatly improve startup time, especially for large executables.
3543 * Remote targets use caching
3545 Remote targets now use a data cache to speed up communication with the
3546 remote side. The data cache could lead to incorrect results because
3547 it doesn't know about volatile variables, thus making it impossible to
3548 debug targets which use memory mapped I/O devices. `set remotecache
3549 off' turns the the data cache off.
3551 * Remote targets may have threads
3553 The standard remote protocol now includes support for multiple threads
3554 in the target system, using new protocol commands 'H' and 'T'. See
3555 gdb/remote.c for details.
3559 If GDB is configured with `--enable-netrom', then it will include
3560 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3561 acts as though it is a bank of ROM on the target board, but you can
3562 write into it over the network. GDB's support consists only of
3563 support for fast loading into the emulated ROM; to debug, you must use
3564 another protocol, such as standard remote protocol. The usual
3565 sequence is something like
3567 target nrom <netrom-hostname>
3569 target remote <netrom-hostname>:1235
3573 GDB now includes support for the Apple Macintosh, as a host only. It
3574 may be run as either an MPW tool or as a standalone application, and
3575 it can debug through the serial port. All the usual GDB commands are
3576 available, but to the target command, you must supply "serial" as the
3577 device type instead of "/dev/ttyXX". See mpw-README in the main
3578 directory for more information on how to build. The MPW configuration
3579 scripts */mpw-config.in support only a few targets, and only the
3580 mips-idt-ecoff target has been tested.
3584 GDB configuration now uses autoconf. This is not user-visible,
3585 but does simplify configuration and building.
3589 GDB now supports hpux10.
3591 *** Changes in GDB-4.14:
3593 * New native configurations
3595 x86 FreeBSD i[345]86-*-freebsd
3596 x86 NetBSD i[345]86-*-netbsd
3597 NS32k NetBSD ns32k-*-netbsd
3598 Sparc NetBSD sparc-*-netbsd
3602 A29K VxWorks a29k-*-vxworks
3603 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3604 CPU32 EST-300 emulator m68*-*-est*
3605 PowerPC ELF powerpc-*-elf
3608 * Alpha OSF/1 support for procfs
3610 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3611 possible to attach to running processes. As the mounting of the /proc
3612 filesystem is optional on the Alpha, GDB automatically determines
3613 the availability of /proc during startup. This can lead to problems
3614 if /proc is unmounted after GDB has been started.
3616 * Arguments to user-defined commands
3618 User commands may accept up to 10 arguments separated by whitespace.
3619 Arguments are accessed within the user command via $arg0..$arg9. A
3622 print $arg0 + $arg1 + $arg2
3624 To execute the command use:
3627 Defines the command "adder" which prints the sum of its three arguments.
3628 Note the arguments are text substitutions, so they may reference variables,
3629 use complex expressions, or even perform inferior function calls.
3631 * New `if' and `while' commands
3633 This makes it possible to write more sophisticated user-defined
3634 commands. Both commands take a single argument, which is the
3635 expression to evaluate, and must be followed by the commands to
3636 execute, one per line, if the expression is nonzero, the list being
3637 terminated by the word `end'. The `if' command list may include an
3638 `else' word, which causes the following commands to be executed only
3639 if the expression is zero.
3641 * Fortran source language mode
3643 GDB now includes partial support for Fortran 77. It will recognize
3644 Fortran programs and can evaluate a subset of Fortran expressions, but
3645 variables and functions may not be handled correctly. GDB will work
3646 with G77, but does not yet know much about symbols emitted by other
3649 * Better HPUX support
3651 Most debugging facilities now work on dynamic executables for HPPAs
3652 running hpux9 or later. You can attach to running dynamically linked
3653 processes, but by default the dynamic libraries will be read-only, so
3654 for instance you won't be able to put breakpoints in them. To change
3655 that behavior do the following before running the program:
3661 This will cause the libraries to be mapped private and read-write.
3662 To revert to the normal behavior, do this:
3668 You cannot set breakpoints or examine data in the library until after
3669 the library is loaded if the function/data symbols do not have
3672 GDB can now also read debug symbols produced by the HP C compiler on
3673 HPPAs (sorry, no C++, Fortran or 68k support).
3675 * Target byte order now dynamically selectable
3677 You can choose which byte order to use with a target system, via the
3678 commands "set endian big" and "set endian little", and you can see the
3679 current setting by using "show endian". You can also give the command
3680 "set endian auto", in which case GDB will use the byte order
3681 associated with the executable. Currently, only embedded MIPS
3682 configurations support dynamic selection of target byte order.
3684 * New DOS host serial code
3686 This version uses DPMI interrupts to handle buffered I/O, so you
3687 no longer need to run asynctsr when debugging boards connected to
3690 *** Changes in GDB-4.13:
3692 * New "complete" command
3694 This lists all the possible completions for the rest of the line, if it
3695 were to be given as a command itself. This is intended for use by emacs.
3697 * Trailing space optional in prompt
3699 "set prompt" no longer adds a space for you after the prompt you set. This
3700 allows you to set a prompt which ends in a space or one that does not.
3702 * Breakpoint hit counts
3704 "info break" now displays a count of the number of times the breakpoint
3705 has been hit. This is especially useful in conjunction with "ignore"; you
3706 can ignore a large number of breakpoint hits, look at the breakpoint info
3707 to see how many times the breakpoint was hit, then run again, ignoring one
3708 less than that number, and this will get you quickly to the last hit of
3711 * Ability to stop printing at NULL character
3713 "set print null-stop" will cause GDB to stop printing the characters of
3714 an array when the first NULL is encountered. This is useful when large
3715 arrays actually contain only short strings.
3717 * Shared library breakpoints
3719 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3720 breakpoints in shared libraries before the executable is run.
3722 * Hardware watchpoints
3724 There is a new hardware breakpoint for the watch command for sparclite
3725 targets. See gdb/sparclite/hw_breakpoint.note.
3727 Hardware watchpoints are also now supported under GNU/Linux.
3731 Annotations have been added. These are for use with graphical interfaces,
3732 and are still experimental. Currently only gdba.el uses these.
3734 * Improved Irix 5 support
3736 GDB now works properly with Irix 5.2.
3738 * Improved HPPA support
3740 GDB now works properly with the latest GCC and GAS.
3742 * New native configurations
3744 Sequent PTX4 i[34]86-sequent-ptx4
3745 HPPA running OSF/1 hppa*-*-osf*
3746 Atari TT running SVR4 m68*-*-sysv4*
3747 RS/6000 LynxOS rs6000-*-lynxos*
3751 OS/9000 i[34]86-*-os9k
3752 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3755 * Hitachi SH7000 and E7000-PC ICE support
3757 There is now support for communicating with the Hitachi E7000-PC ICE.
3758 This is available automatically when GDB is configured for the SH.
3762 As usual, a variety of small fixes and improvements, both generic
3763 and configuration-specific. See the ChangeLog for more detail.
3765 *** Changes in GDB-4.12:
3767 * Irix 5 is now supported
3771 GDB-4.12 on the HPPA has a number of changes which make it unable
3772 to debug the output from the currently released versions of GCC and
3773 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3774 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3775 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3778 *** Changes in GDB-4.11:
3780 * User visible changes:
3784 The "set remotedebug" option is now consistent between the mips remote
3785 target, remote targets using the gdb-specific protocol, UDI (AMD's
3786 debug protocol for the 29k) and the 88k bug monitor. It is now an
3787 integer specifying a debug level (normally 0 or 1, but 2 means more
3788 debugging info for the mips target).
3790 * DEC Alpha native support
3792 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3793 debug info, but GDB works fairly well with the DEC compiler and should
3794 work with a future GCC release. See the README file for a few
3795 Alpha-specific notes.
3797 * Preliminary thread implementation
3799 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3801 * LynxOS native and target support for 386
3803 This release has been hosted on LynxOS 2.2, and also can be configured
3804 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3807 * Improvements in C++ mangling/demangling.
3809 This release has much better g++ debugging, specifically in name
3810 mangling/demangling, virtual function calls, print virtual table,
3811 call methods, ...etc.
3813 *** Changes in GDB-4.10:
3815 * User visible changes:
3817 Remote debugging using the GDB-specific (`target remote') protocol now
3818 supports the `load' command. This is only useful if you have some
3819 other way of getting the stub to the target system, and you can put it
3820 somewhere in memory where it won't get clobbered by the download.
3822 Filename completion now works.
3824 When run under emacs mode, the "info line" command now causes the
3825 arrow to point to the line specified. Also, "info line" prints
3826 addresses in symbolic form (as well as hex).
3828 All vxworks based targets now support a user settable option, called
3829 vxworks-timeout. This option represents the number of seconds gdb
3830 should wait for responses to rpc's. You might want to use this if
3831 your vxworks target is, perhaps, a slow software simulator or happens
3832 to be on the far side of a thin network line.
3836 This release contains support for using a DEC alpha as a GDB host for
3837 cross debugging. Native alpha debugging is not supported yet.
3840 *** Changes in GDB-4.9:
3844 This is the first GDB release which is accompanied by a matching testsuite.
3845 The testsuite requires installation of dejagnu, which should be available
3846 via ftp from most sites that carry GNU software.
3850 'Cfront' style demangling has had its name changed to 'ARM' style, to
3851 emphasize that it was written from the specifications in the C++ Annotated
3852 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3853 disclaimers, it still generated too much confusion with users attempting to
3854 use gdb with AT&T cfront.
3858 GDB now uses a standard remote interface to a simulator library.
3859 So far, the library contains simulators for the Zilog Z8001/2, the
3860 Hitachi H8/300, H8/500 and Super-H.
3862 * New targets supported
3864 H8/300 simulator h8300-hitachi-hms or h8300hms
3865 H8/500 simulator h8500-hitachi-hms or h8500hms
3866 SH simulator sh-hitachi-hms or sh
3867 Z8000 simulator z8k-zilog-none or z8ksim
3868 IDT MIPS board over serial line mips-idt-ecoff
3870 Cross-debugging to GO32 targets is supported. It requires a custom
3871 version of the i386-stub.c module which is integrated with the
3872 GO32 memory extender.
3874 * New remote protocols
3876 MIPS remote debugging protocol.
3878 * New source languages supported
3880 This version includes preliminary support for Chill, a Pascal like language
3881 used by telecommunications companies. Chill support is also being integrated
3882 into the GNU compiler, but we don't know when it will be publically available.
3885 *** Changes in GDB-4.8:
3887 * HP Precision Architecture supported
3889 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3890 version of this support was available as a set of patches from the
3891 University of Utah. GDB does not support debugging of programs
3892 compiled with the HP compiler, because HP will not document their file
3893 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3894 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3896 Many problems in the preliminary version have been fixed.
3898 * Faster and better demangling
3900 We have improved template demangling and fixed numerous bugs in the GNU style
3901 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3902 character types (wchar_t) are now supported. Demangling of each symbol is now
3903 only done once, and is cached when the symbol table for a file is read in.
3904 This results in a small increase in memory usage for C programs, a moderate
3905 increase in memory usage for C++ programs, and a fantastic speedup in
3908 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3909 from the specifications in the Annotated Reference Manual, which AT&T's
3910 compiler does not actually implement.
3912 * G++ multiple inheritance compiler problem
3914 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3915 inheritance lattices was reworked to properly discover ambiguities. We
3916 recently found an example which causes this new algorithm to fail in a
3917 very subtle way, producing bad debug information for those classes.
3918 The file 'gcc.patch' (in this directory) can be applied to gcc to
3919 circumvent the problem. A future GCC release will contain a complete
3922 The previous G++ debug info problem (mentioned below for the gdb-4.7
3923 release) is fixed in gcc version 2.3.2.
3925 * Improved configure script
3927 The `configure' script will now attempt to guess your system type if
3928 you don't supply a host system type. The old scheme of supplying a
3929 host system triplet is preferable over using this. All the magic is
3930 done in the new `config.guess' script. Examine it for details.
3932 We have also brought our configure script much more in line with the FSF's
3933 version. It now supports the --with-xxx options. In particular,
3934 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3935 The resulting GDB will not be able to read arbitrary object file formats --
3936 only the format ``expected'' to be used on the configured target system.
3937 We hope to make this the default in a future release.
3939 * Documentation improvements
3941 There's new internal documentation on how to modify GDB, and how to
3942 produce clean changes to the code. We implore people to read it
3943 before submitting changes.
3945 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3946 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3947 `info' files are also provided. To build `info' files from scratch,
3948 you will need the latest `makeinfo' release, which will be available in
3949 a future texinfo-X.Y release.
3951 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3952 We're not sure exactly which versions have this problem, but it has
3953 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3954 or better. If that isn't possible, there is a patch in
3955 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3956 around this problem.
3960 GDB now supports array constants that can be used in expressions typed in by
3961 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3962 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3965 The new directory `gdb/sparclite' contains a program that demonstrates
3966 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3968 * New native hosts supported
3970 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3971 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3973 * New targets supported
3975 AMD 29k family via UDI a29k-amd-udi or udi29k
3977 * New file formats supported
3979 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3980 HPUX core files, and SCO 3.2v2 core files.
3984 Attaching to processes now works again; thanks for the many bug reports.
3986 We have also stomped on a bunch of core dumps caused by
3987 printf_filtered("%s") problems.
3989 We eliminated a copyright problem on the rpc and ptrace header files
3990 for VxWorks, which was discovered at the last minute during the 4.7
3991 release. You should now be able to build a VxWorks GDB.
3993 You can now interrupt gdb while an attached process is running. This
3994 will cause the attached process to stop, and give control back to GDB.
3996 We fixed problems caused by using too many file descriptors
3997 for reading symbols from object files and libraries. This was
3998 especially a problem for programs that used many (~100) shared
4001 The `step' command now only enters a subroutine if there is line number
4002 information for the subroutine. Otherwise it acts like the `next'
4003 command. Previously, `step' would enter subroutines if there was
4004 any debugging information about the routine. This avoids problems
4005 when using `cc -g1' on MIPS machines.
4007 * Internal improvements
4009 GDB's internal interfaces have been improved to make it easier to support
4010 debugging of multiple languages in the future.
4012 GDB now uses a common structure for symbol information internally.
4013 Minimal symbols (derived from linkage symbols in object files), partial
4014 symbols (from a quick scan of debug information), and full symbols
4015 contain a common subset of information, making it easier to write
4016 shared code that handles any of them.
4018 * New command line options
4020 We now accept --silent as an alias for --quiet.
4024 The memory-mapped-malloc library is now licensed under the GNU Library
4025 General Public License.
4027 *** Changes in GDB-4.7:
4029 * Host/native/target split
4031 GDB has had some major internal surgery to untangle the support for
4032 hosts and remote targets. Now, when you configure GDB for a remote
4033 target, it will no longer load in all of the support for debugging
4034 local programs on the host. When fully completed and tested, this will
4035 ensure that arbitrary host/target combinations are possible.
4037 The primary conceptual shift is to separate the non-portable code in
4038 GDB into three categories. Host specific code is required any time GDB
4039 is compiled on that host, regardless of the target. Target specific
4040 code relates to the peculiarities of the target, but can be compiled on
4041 any host. Native specific code is everything else: it can only be
4042 built when the host and target are the same system. Child process
4043 handling and core file support are two common `native' examples.
4045 GDB's use of /proc for controlling Unix child processes is now cleaner.
4046 It has been split out into a single module under the `target_ops' vector,
4047 plus two native-dependent functions for each system that uses /proc.
4049 * New hosts supported
4051 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4052 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4053 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4055 * New targets supported
4057 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4058 68030 and CPU32 m68030-*-*, m68332-*-*
4060 * New native hosts supported
4062 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4063 (386bsd is not well tested yet)
4064 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4066 * New file formats supported
4068 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4069 supports reading of `a.out.adobe' object files, which are an a.out
4070 format extended with minimal information about multiple sections.
4074 `show copying' is the same as the old `info copying'.
4075 `show warranty' is the same as `info warrantee'.
4076 These were renamed for consistency. The old commands continue to work.
4078 `info handle' is a new alias for `info signals'.
4080 You can now define pre-command hooks, which attach arbitrary command
4081 scripts to any command. The commands in the hook will be executed
4082 prior to the user's command. You can also create a hook which will be
4083 executed whenever the program stops. See gdb.texinfo.
4087 We now deal with Cfront style name mangling, and can even extract type
4088 info from mangled symbols. GDB can automatically figure out which
4089 symbol mangling style your C++ compiler uses.
4091 Calling of methods and virtual functions has been improved as well.
4095 The crash that occured when debugging Sun Ansi-C compiled binaries is
4096 fixed. This was due to mishandling of the extra N_SO stabs output
4099 We also finally got Ultrix 4.2 running in house, and fixed core file
4100 support, with help from a dozen people on the net.
4102 John M. Farrell discovered that the reason that single-stepping was so
4103 slow on all of the Mips based platforms (primarily SGI and DEC) was
4104 that we were trying to demangle and lookup a symbol used for internal
4105 purposes on every instruction that was being stepped through. Changing
4106 the name of that symbol so that it couldn't be mistaken for a C++
4107 mangled symbol sped things up a great deal.
4109 Rich Pixley sped up symbol lookups in general by getting much smarter
4110 about when C++ symbol mangling is necessary. This should make symbol
4111 completion (TAB on the command line) much faster. It's not as fast as
4112 we'd like, but it's significantly faster than gdb-4.6.
4116 A new user controllable variable 'call_scratch_address' can
4117 specify the location of a scratch area to be used when GDB
4118 calls a function in the target. This is necessary because the
4119 usual method of putting the scratch area on the stack does not work
4120 in systems that have separate instruction and data spaces.
4122 We integrated changes to support the 29k UDI (Universal Debugger
4123 Interface), but discovered at the last minute that we didn't have all
4124 of the appropriate copyright paperwork. We are working with AMD to
4125 resolve this, and hope to have it available soon.
4129 We have sped up the remote serial line protocol, especially for targets
4130 with lots of registers. It now supports a new `expedited status' ('T')
4131 message which can be used in place of the existing 'S' status message.
4132 This allows the remote stub to send only the registers that GDB
4133 needs to make a quick decision about single-stepping or conditional
4134 breakpoints, eliminating the need to fetch the entire register set for
4135 each instruction being stepped through.
4137 The GDB remote serial protocol now implements a write-through cache for
4138 registers, only re-reading the registers if the target has run.
4140 There is also a new remote serial stub for SPARC processors. You can
4141 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4142 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4143 processor with a serial port.
4147 Configure.in files have become much easier to read and modify. A new
4148 `table driven' format makes it more obvious what configurations are
4149 supported, and what files each one uses.
4153 There is a new opcodes library which will eventually contain all of the
4154 disassembly routines and opcode tables. At present, it only contains
4155 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4156 disassembler (binutils/objdump) to share these routines.
4158 The libiberty library is now copylefted under the GNU Library General
4159 Public License. This allows more liberal use, and was done so libg++
4160 can use it. This makes no difference to GDB, since the Library License
4161 grants all the rights from the General Public License.
4165 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4166 reference to the stabs symbol info used by the debugger. It is (as far
4167 as we know) the only published document on this fascinating topic. We
4168 encourage you to read it, compare it to the stabs information on your
4169 system, and send improvements on the document in general (to
4170 bug-gdb@prep.ai.mit.edu).
4172 And, of course, many bugs have been fixed.
4175 *** Changes in GDB-4.6:
4177 * Better support for C++ function names
4179 GDB now accepts as input the "demangled form" of C++ overloaded function
4180 names and member function names, and can do command completion on such names
4181 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4182 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4183 Make use of command completion, it is your friend.
4185 GDB also now accepts a variety of C++ mangled symbol formats. They are
4186 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4187 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4188 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4189 for the list of formats.
4191 * G++ symbol mangling problem
4193 Recent versions of gcc have a bug in how they emit debugging information for
4194 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4195 directory) can be applied to gcc to fix the problem. Alternatively, if you
4196 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4197 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4198 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4201 * New 'maintenance' command
4203 All of the commands related to hacking GDB internals have been moved out of
4204 the main command set, and now live behind the 'maintenance' command. This
4205 can also be abbreviated as 'mt'. The following changes were made:
4207 dump-me -> maintenance dump-me
4208 info all-breakpoints -> maintenance info breakpoints
4209 printmsyms -> maintenance print msyms
4210 printobjfiles -> maintenance print objfiles
4211 printpsyms -> maintenance print psymbols
4212 printsyms -> maintenance print symbols
4214 The following commands are new:
4216 maintenance demangle Call internal GDB demangler routine to
4217 demangle a C++ link name and prints the result.
4218 maintenance print type Print a type chain for a given symbol
4220 * Change to .gdbinit file processing
4222 We now read the $HOME/.gdbinit file before processing the argv arguments
4223 (e.g. reading symbol files or core files). This allows global parameters to
4224 be set, which will apply during the symbol reading. The ./.gdbinit is still
4225 read after argv processing.
4227 * New hosts supported
4229 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4231 GNU/Linux support i386-unknown-linux or linux
4233 We are also including code to support the HP/PA running BSD and HPUX. This
4234 is almost guaranteed not to work, as we didn't have time to test or build it
4235 for this release. We are including it so that the more adventurous (or
4236 masochistic) of you can play with it. We also had major problems with the
4237 fact that the compiler that we got from HP doesn't support the -g option.
4240 * New targets supported
4242 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4244 * More smarts about finding #include files
4246 GDB now remembers the compilation directory for all include files, and for
4247 all files from which C is generated (like yacc and lex sources). This
4248 greatly improves GDB's ability to find yacc/lex sources, and include files,
4249 especially if you are debugging your program from a directory different from
4250 the one that contains your sources.
4252 We also fixed a bug which caused difficulty with listing and setting
4253 breakpoints in include files which contain C code. (In the past, you had to
4254 try twice in order to list an include file that you hadn't looked at before.)
4256 * Interesting infernals change
4258 GDB now deals with arbitrary numbers of sections, where the symbols for each
4259 section must be relocated relative to that section's landing place in the
4260 target's address space. This work was needed to support ELF with embedded
4261 stabs used by Solaris-2.0.
4263 * Bug fixes (of course!)
4265 There have been loads of fixes for the following things:
4266 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4267 i960, stabs, DOS(GO32), procfs, etc...
4269 See the ChangeLog for details.
4271 *** Changes in GDB-4.5:
4273 * New machines supported (host and target)
4275 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4277 SGI Irix-4.x mips-sgi-irix4 or iris4
4279 * New malloc package
4281 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4282 Mmalloc is capable of handling mutiple heaps of memory. It is also
4283 capable of saving a heap to a file, and then mapping it back in later.
4284 This can be used to greatly speedup the startup of GDB by using a
4285 pre-parsed symbol table which lives in a mmalloc managed heap. For
4286 more details, please read mmalloc/mmalloc.texi.
4290 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4291 'help info proc' for details.
4293 * MIPS ecoff symbol table format
4295 The code that reads MIPS symbol table format is now supported on all hosts.
4296 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4299 * File name changes for MS-DOS
4301 Many files in the config directories have been renamed to make it easier to
4302 support GDB on MS-DOSe systems (which have very restrictive file name
4303 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4304 environment) is close to working but has some remaining problems. Note
4305 that debugging of DOS programs is not supported, due to limitations
4306 in the ``operating system'', but it can be used to host cross-debugging.
4308 * Cross byte order fixes
4310 Many fixes have been made to support cross debugging of Sparc and MIPS
4311 targets from hosts whose byte order differs.
4313 * New -mapped and -readnow options
4315 If memory-mapped files are available on your system through the 'mmap'
4316 system call, you can use the -mapped option on the `file' or
4317 `symbol-file' commands to cause GDB to write the symbols from your
4318 program into a reusable file. If the program you are debugging is
4319 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4320 Future GDB debugging sessions will notice the presence of this file,
4321 and will quickly map in symbol information from it, rather than reading
4322 the symbol table from the executable program. Using the '-mapped'
4323 option in a GDB `file' or `symbol-file' command has the same effect as
4324 starting GDB with the '-mapped' command-line option.
4326 You can cause GDB to read the entire symbol table immediately by using
4327 the '-readnow' option with any of the commands that load symbol table
4328 information (or on the GDB command line). This makes the command
4329 slower, but makes future operations faster.
4331 The -mapped and -readnow options are typically combined in order to
4332 build a `fred.syms' file that contains complete symbol information.
4333 A simple GDB invocation to do nothing but build a `.syms' file for future
4336 gdb -batch -nx -mapped -readnow programname
4338 The `.syms' file is specific to the host machine on which GDB is run.
4339 It holds an exact image of GDB's internal symbol table. It cannot be
4340 shared across multiple host platforms.
4342 * longjmp() handling
4344 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4345 siglongjmp() without losing control. This feature has not yet been ported to
4346 all systems. It currently works on many 386 platforms, all MIPS-based
4347 platforms (SGI, DECstation, etc), and Sun3/4.
4351 Preliminary work has been put in to support the new Solaris OS from Sun. At
4352 this time, it can control and debug processes, but it is not capable of
4357 As always, many many bug fixes. The major areas were with g++, and mipsread.
4358 People using the MIPS-based platforms should experience fewer mysterious
4359 crashes and trashed symbol tables.
4361 *** Changes in GDB-4.4:
4363 * New machines supported (host and target)
4365 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4367 BSD Reno on Vax vax-dec-bsd
4368 Ultrix on Vax vax-dec-ultrix
4370 * New machines supported (target)
4372 AMD 29000 embedded, using EBMON a29k-none-none
4376 GDB continues to improve its handling of C++. `References' work better.
4377 The demangler has also been improved, and now deals with symbols mangled as
4378 per the Annotated C++ Reference Guide.
4380 GDB also now handles `stabs' symbol information embedded in MIPS
4381 `ecoff' symbol tables. Since the ecoff format was not easily
4382 extensible to handle new languages such as C++, this appeared to be a
4383 good way to put C++ debugging info into MIPS binaries. This option
4384 will be supported in the GNU C compiler, version 2, when it is
4387 * New features for SVR4
4389 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4390 shared libraries. Debugging dynamically linked programs should present
4391 only minor differences from debugging statically linked programs.
4393 The `info proc' command will print out information about any process
4394 on an SVR4 system (including the one you are debugging). At the moment,
4395 it prints the address mappings of the process.
4397 If you bring up GDB on another SVR4 system, please send mail to
4398 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4400 * Better dynamic linking support in SunOS
4402 Reading symbols from shared libraries which contain debugging symbols
4403 now works properly. However, there remain issues such as automatic
4404 skipping of `transfer vector' code during function calls, which
4405 make it harder to debug code in a shared library, than to debug the
4406 same code linked statically.
4410 GDB is now using the latest `getopt' routines from the FSF. This
4411 version accepts the -- prefix for options with long names. GDB will
4412 continue to accept the old forms (-option and +option) as well.
4413 Various single letter abbreviations for options have been explicity
4414 added to the option table so that they won't get overshadowed in the
4415 future by other options that begin with the same letter.
4419 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4420 Many assorted bugs have been handled. Many more remain to be handled.
4421 See the various ChangeLog files (primarily in gdb and bfd) for details.
4424 *** Changes in GDB-4.3:
4426 * New machines supported (host and target)
4428 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4429 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4430 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4432 * Almost SCO Unix support
4434 We had hoped to support:
4435 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4436 (except for core file support), but we discovered very late in the release
4437 that it has problems with process groups that render gdb unusable. Sorry
4438 about that. I encourage people to fix it and post the fixes.
4440 * Preliminary ELF and DWARF support
4442 GDB can read ELF object files on System V Release 4, and can handle
4443 debugging records for C, in DWARF format, in ELF files. This support
4444 is preliminary. If you bring up GDB on another SVR4 system, please
4445 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4450 GDB now uses the latest `readline' library. One user-visible change
4451 is that two tabs will list possible command completions, which previously
4452 required typing M-? (meta-question mark, or ESC ?).
4456 The `stepi' bug that many of you noticed has been squashed.
4457 Many bugs in C++ have been handled. Many more remain to be handled.
4458 See the various ChangeLog files (primarily in gdb and bfd) for details.
4460 * State of the MIPS world (in case you wondered):
4462 GDB can understand the symbol tables emitted by the compilers
4463 supplied by most vendors of MIPS-based machines, including DEC. These
4464 symbol tables are in a format that essentially nobody else uses.
4466 Some versions of gcc come with an assembler post-processor called
4467 mips-tfile. This program is required if you want to do source-level
4468 debugging of gcc-compiled programs. I believe FSF does not ship
4469 mips-tfile with gcc version 1, but it will eventually come with gcc
4472 Debugging of g++ output remains a problem. g++ version 1.xx does not
4473 really support it at all. (If you're lucky, you should be able to get
4474 line numbers and stack traces to work, but no parameters or local
4475 variables.) With some work it should be possible to improve the
4478 When gcc version 2 is released, you will have somewhat better luck.
4479 However, even then you will get confusing results for inheritance and
4482 We will eventually provide full debugging of g++ output on
4483 DECstations. This will probably involve some kind of stabs-in-ecoff
4484 encapulation, but the details have not been worked out yet.
4487 *** Changes in GDB-4.2:
4489 * Improved configuration
4491 Only one copy of `configure' exists now, and it is not self-modifying.
4492 Porting BFD is simpler.
4496 The `step' and `next' commands now only stop at the first instruction
4497 of a source line. This prevents the multiple stops that used to occur
4498 in switch statements, for-loops, etc. `Step' continues to stop if a
4499 function that has debugging information is called within the line.
4503 Lots of small bugs fixed. More remain.
4505 * New host supported (not target)
4507 Intel 386 PC clone running Mach i386-none-mach
4510 *** Changes in GDB-4.1:
4512 * Multiple source language support
4514 GDB now has internal scaffolding to handle several source languages.
4515 It determines the type of each source file from its filename extension,
4516 and will switch expression parsing and number formatting to match the
4517 language of the function in the currently selected stack frame.
4518 You can also specifically set the language to be used, with
4519 `set language c' or `set language modula-2'.
4523 GDB now has preliminary support for the GNU Modula-2 compiler,
4524 currently under development at the State University of New York at
4525 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4526 continue through the fall of 1991 and into 1992.
4528 Other Modula-2 compilers are currently not supported, and attempting to
4529 debug programs compiled with them will likely result in an error as the
4530 symbol table is read. Feel free to work on it, though!
4532 There are hooks in GDB for strict type checking and range checking,
4533 in the `Modula-2 philosophy', but they do not currently work.
4537 GDB can now write to executable and core files (e.g. patch
4538 a variable's value). You must turn this switch on, specify
4539 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4540 by assigning a new value to a variable. Modifications take
4543 * Automatic SunOS shared library reading
4545 When you run your program, GDB automatically determines where its
4546 shared libraries (if any) have been loaded, and reads their symbols.
4547 The `share' command is no longer needed. This also works when
4548 examining core files.
4552 You can specify the number of lines that the `list' command shows.
4555 * New machines supported (host and target)
4557 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4558 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4559 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4561 * New hosts supported (not targets)
4563 IBM RT/PC: romp-ibm-aix or rtpc
4565 * New targets supported (not hosts)
4567 AMD 29000 embedded with COFF a29k-none-coff
4568 AMD 29000 embedded with a.out a29k-none-aout
4569 Ultracomputer remote kernel debug a29k-nyu-kern
4571 * New remote interfaces
4577 *** Changes in GDB-4.0:
4581 Wide output is wrapped at good places to make the output more readable.
4583 Gdb now supports cross-debugging from a host machine of one type to a
4584 target machine of another type. Communication with the target system
4585 is over serial lines. The ``target'' command handles connecting to the
4586 remote system; the ``load'' command will download a program into the
4587 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4588 also supports debugging of realtime processes running under VxWorks,
4589 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4590 stub on the target system.
4592 New CPUs supported include the AMD 29000 and Intel 960.
4594 GDB now reads object files and symbol tables via a ``binary file''
4595 library, which allows a single copy of GDB to debug programs of multiple
4596 object file types such as a.out and coff.
4598 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4599 refcard.dvi and refcard.ps are available to format it).
4602 * Control-Variable user interface simplified
4604 All variables that control the operation of the debugger can be set
4605 by the ``set'' command, and displayed by the ``show'' command.
4607 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4608 ``Show prompt'' produces the response:
4609 Gdb's prompt is new-gdb=>.
4611 What follows are the NEW set commands. The command ``help set'' will
4612 print a complete list of old and new set commands. ``help set FOO''
4613 will give a longer description of the variable FOO. ``show'' will show
4614 all of the variable descriptions and their current settings.
4616 confirm on/off: Enables warning questions for operations that are
4617 hard to recover from, e.g. rerunning the program while
4618 it is already running. Default is ON.
4620 editing on/off: Enables EMACS style command line editing
4621 of input. Previous lines can be recalled with
4622 control-P, the current line can be edited with control-B,
4623 you can search for commands with control-R, etc.
4626 history filename NAME: NAME is where the gdb command history
4627 will be stored. The default is .gdb_history,
4628 or the value of the environment variable
4631 history size N: The size, in commands, of the command history. The
4632 default is 256, or the value of the environment variable
4635 history save on/off: If this value is set to ON, the history file will
4636 be saved after exiting gdb. If set to OFF, the
4637 file will not be saved. The default is OFF.
4639 history expansion on/off: If this value is set to ON, then csh-like
4640 history expansion will be performed on
4641 command line input. The default is OFF.
4643 radix N: Sets the default radix for input and output. It can be set
4644 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4645 in the current radix, so "set radix 10" is always a no-op.
4647 height N: This integer value is the number of lines on a page. Default
4648 is 24, the current `stty rows'' setting, or the ``li#''
4649 setting from the termcap entry matching the environment
4652 width N: This integer value is the number of characters on a line.
4653 Default is 80, the current `stty cols'' setting, or the ``co#''
4654 setting from the termcap entry matching the environment
4657 Note: ``set screensize'' is obsolete. Use ``set height'' and
4658 ``set width'' instead.
4660 print address on/off: Print memory addresses in various command displays,
4661 such as stack traces and structure values. Gdb looks
4662 more ``symbolic'' if you turn this off; it looks more
4663 ``machine level'' with it on. Default is ON.
4665 print array on/off: Prettyprint arrays. New convenient format! Default
4668 print demangle on/off: Print C++ symbols in "source" form if on,
4671 print asm-demangle on/off: Same, for assembler level printouts
4674 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4677 * Support for Epoch Environment.
4679 The epoch environment is a version of Emacs v18 with windowing. One
4680 new command, ``inspect'', is identical to ``print'', except that if you
4681 are running in the epoch environment, the value is printed in its own
4685 * Support for Shared Libraries
4687 GDB can now debug programs and core files that use SunOS shared libraries.
4688 Symbols from a shared library cannot be referenced
4689 before the shared library has been linked with the program (this
4690 happens after you type ``run'' and before the function main() is entered).
4691 At any time after this linking (including when examining core files
4692 from dynamically linked programs), gdb reads the symbols from each
4693 shared library when you type the ``sharedlibrary'' command.
4694 It can be abbreviated ``share''.
4696 sharedlibrary REGEXP: Load shared object library symbols for files
4697 matching a unix regular expression. No argument
4698 indicates to load symbols for all shared libraries.
4700 info sharedlibrary: Status of loaded shared libraries.
4705 A watchpoint stops execution of a program whenever the value of an
4706 expression changes. Checking for this slows down execution
4707 tremendously whenever you are in the scope of the expression, but is
4708 quite useful for catching tough ``bit-spreader'' or pointer misuse
4709 problems. Some machines such as the 386 have hardware for doing this
4710 more quickly, and future versions of gdb will use this hardware.
4712 watch EXP: Set a watchpoint (breakpoint) for an expression.
4714 info watchpoints: Information about your watchpoints.
4716 delete N: Deletes watchpoint number N (same as breakpoints).
4717 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4718 enable N: Re-enables watchpoint number N (same as breakpoints).
4721 * C++ multiple inheritance
4723 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4726 * C++ exception handling
4728 Gdb now supports limited C++ exception handling. Besides the existing
4729 ability to breakpoint on an exception handler, gdb can breakpoint on
4730 the raising of an exception (before the stack is peeled back to the
4733 catch FOO: If there is a FOO exception handler in the dynamic scope,
4734 set a breakpoint to catch exceptions which may be raised there.
4735 Multiple exceptions (``catch foo bar baz'') may be caught.
4737 info catch: Lists all exceptions which may be caught in the
4738 current stack frame.
4741 * Minor command changes
4743 The command ``call func (arg, arg, ...)'' now acts like the print
4744 command, except it does not print or save a value if the function's result
4745 is void. This is similar to dbx usage.
4747 The ``up'' and ``down'' commands now always print the frame they end up
4748 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4749 frames without printing.
4751 * New directory command
4753 'dir' now adds directories to the FRONT of the source search path.
4754 The path starts off empty. Source files that contain debug information
4755 about the directory in which they were compiled can be found even
4756 with an empty path; Sun CC and GCC include this information. If GDB can't
4757 find your source file in the current directory, type "dir .".
4759 * Configuring GDB for compilation
4761 For normal use, type ``./configure host''. See README or gdb.texinfo
4764 GDB now handles cross debugging. If you are remotely debugging between
4765 two different machines, type ``./configure host -target=targ''.
4766 Host is the machine where GDB will run; targ is the machine
4767 where the program that you are debugging will run.