1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.4
6 * GDBserver now supports stdio connections.
7 E.g. (gdb) target remote | ssh myhost gdbserver - hello
11 * GDB now handles ambiguous linespecs more consistently; the existing
12 FILE:LINE support has been expanded to other types of linespecs. A
13 breakpoint will now be set on all matching locations in all
14 inferiors, and locations will be added or removed according to
17 * GDB now allows you to skip uninteresting functions and files when
18 stepping with the "skip function" and "skip file" commands.
20 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
21 and "show remote hardware-watchpoint-length-limit". These allows to
22 set or show the maximum length limit (in bytes) of a remote
23 target hardware watchpoint.
25 This allows e.g. to use "unlimited" hardware watchpoints with the
26 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
27 watchpoints are slower than real hardware watchpoints but are
28 significantly faster than gdb software watchpoints.
32 ** The register_pretty_printer function in module gdb.printing now takes
33 an optional `replace' argument. If True, the new printer replaces any
36 ** The "maint set python print-stack on|off" command has been
37 removed. A new command: "set python print-stack
38 none|full|message" has replaced it. Additionally, the default
39 for "print-stack" is now "message", which just prints the error
40 message without the stack trace.
42 ** A prompt substitution hook (prompt_hook) is now available to the
45 ** A new Python module, gdb.prompt has been added to the GDB Python
46 modules library. This module provides functionality for
47 escape sequences in prompts (used by set/show
48 extended-prompt). These escape sequences are replaced by their
51 ** Python commands and convenience-functions located in
52 'data-directory'/python/gdb/command and
53 'data-directory'/python/gdb/function are now automatically loaded
56 ** Blocks now provide four new attributes. global_block and
57 static_block will return the global and static blocks
58 respectively. is_static and is_global are boolean attributes
59 that indicate if the block is one of those two types.
61 ** Symbols now provide the "type" attribute, the type of the symbol.
63 ** The "gdb.breakpoint" function has been deprecated in favor of
66 ** Type objects for struct and union types now allow access to
67 the fields using standard Python dictionary (mapping) methods.
68 For example, "some_type['myfield']" now works, as does
71 ** A new event "gdb.new_objfile" has been added, triggered by loading a
74 ** A new function, "deep_items" has been added to the gdb.types
75 module in the GDB Python modules library. This function returns
76 an iterator over the fields of a struct or union type. Unlike
77 the standard Python "iteritems" method, it will recursively traverse
82 ** "*stopped" events can report several new "reason"s, such as
85 ** Breakpoint changes are now notified using new async records, like
86 "=breakpoint-modified".
88 ** New command -ada-task-info.
90 * libthread-db-search-path now supports two special values: $sdir and $pdir.
91 $sdir specifies the default system locations of shared libraries.
92 $pdir specifies the directory where the libpthread used by the application
95 GDB no longer looks in $sdir and $pdir after it has searched the directories
96 mentioned in libthread-db-search-path. If you want to search those
97 directories, they must be specified in libthread-db-search-path.
98 The default value of libthread-db-search-path on GNU/Linux and Solaris
99 systems is now "$sdir:$pdir".
101 $pdir is not supported by gdbserver, it is currently ignored.
102 $sdir is supported by gdbserver.
104 * New configure option --with-iconv-bin.
105 When using the internationalization support like the one in the GNU C
106 library, GDB will invoke the "iconv" program to get a list of supported
107 character sets. If this program lives in a non-standard location, one can
108 use this option to specify where to find it.
110 * When natively debugging programs on PowerPC BookE processors running
111 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
112 watchpoints, which specify a mask in addition to an address to watch.
113 The mask specifies that some bits of an address (the bits which are
114 reset in the mask) should be ignored when matching the address accessed
115 by the inferior against the watchpoint address. See the "PowerPC Embedded"
116 section in the user manual for more details.
118 * The new option --once causes GDBserver to stop listening for connections once
119 the first connection is made. The listening port used by GDBserver will
120 become available after that.
122 * New commands "info macros" and "alias" have been added.
124 * New function parameters suffix @entry specifies value of function parameter
125 at the time the function got called. Entry values are available only since
131 "!" is now an alias of the "shell" command.
132 Note that no space is needed between "!" and SHELL COMMAND.
136 watch EXPRESSION mask MASK_VALUE
137 The watch command now supports the mask argument which allows creation
138 of masked watchpoints, if the current architecture supports this feature.
140 info auto-load-scripts [REGEXP]
141 This command was formerly named "maintenance print section-scripts".
142 It is now generally useful and is no longer a maintenance-only command.
144 info macro [-all] [--] MACRO
145 The info macro command has new options `-all' and `--'. The first for
146 printing all definitions of a macro. The second for explicitly specifying
147 the end of arguments and the beginning of the macro name in case the macro
148 name starts with a hyphen.
150 collect[/s] EXPRESSIONS
151 The tracepoint collect command now takes an optional modifier "/s"
152 that directs it to dereference pointer-to-character types and
153 collect the bytes of memory up to a zero byte. The behavior is
154 similar to what you see when you use the regular print command on a
155 string. An optional integer following the "/s" sets a bound on the
156 number of bytes that will be collected.
159 The trace start command now interprets any supplied arguments as a
160 note to be recorded with the trace run, with an effect similar to
161 setting the variable trace-notes.
164 The trace stop command now interprets any arguments as a note to be
165 mentioned along with the tstatus report that the trace was stopped
166 with a command. The effect is similar to setting the variable
169 * Tracepoints can now be enabled and disabled at any time after a trace
170 experiment has been started using the standard "enable" and "disable"
171 commands. It is now possible to start a trace experiment with no enabled
172 tracepoints; GDB will display a warning, but will allow the experiment to
173 begin, assuming that tracepoints will be enabled as needed while the trace
176 * Fast tracepoints on 32-bit x86-architectures can now be placed at
177 locations with 4-byte instructions, when they were previously
178 limited to locations with instructions of 5 bytes or longer.
184 Set the GDB prompt, and allow escape sequences to be inserted to
185 display miscellaneous information (see 'help set extended-prompt'
186 for the list of sequences). This prompt (and any information
187 accessed through the escape sequences) is updated every time the
190 set print entry-values (both|compact|default|if-needed|no|only|preferred)
191 show print entry-values
192 Set printing of frame argument values at function entry. In some cases
193 GDB can determine the value of function argument which was passed by the
194 function caller, even if the value was modified inside the called function.
196 set debug entry-values
197 show debug entry-values
198 Control display of debugging info for determining frame argument values at
199 function entry and virtual tail call frames.
201 set basenames-may-differ
202 show basenames-may-differ
203 Set whether a source file may have multiple base names.
204 (A "base name" is the name of a file with the directory part removed.
205 Example: The base name of "/home/user/hello.c" is "hello.c".)
206 If set, GDB will canonicalize file names (e.g., expand symlinks)
207 before comparing them. Canonicalization is an expensive operation,
208 but it allows the same file be known by more than one base name.
209 If not set (the default), all source files are assumed to have just
210 one base name, and gdb will do file name comparisons more efficiently.
216 Set a user name and notes for the current and any future trace runs.
217 This is useful for long-running and/or disconnected traces, to
218 inform others (or yourself) as to who is running the trace, supply
219 contact information, or otherwise explain what is going on.
222 show trace-stop-notes
223 Set a note attached to the trace run, that is displayed when the
224 trace has been stopped by a tstop command. This is useful for
225 instance as an explanation, if you are stopping a trace run that was
226 started by someone else.
232 Dynamically enable a tracepoint in a started trace experiment.
236 Dynamically disable a tracepoint in a started trace experiment.
240 Set the user and notes of the trace run.
244 Query the current status of a tracepoint.
248 Query the minimum length of instruction at which a fast tracepoint may
251 * Dcache size (number of lines) and line-size are now runtime-configurable
252 via "set dcache line" and "set dcache line-size" commands.
256 Texas Instruments TMS320C6x tic6x-*-*
260 Renesas RL78 rl78-*-elf
262 *** Changes in GDB 7.3.1
264 * The build failure for NetBSD and OpenBSD targets have now been fixed.
266 *** Changes in GDB 7.3
268 * GDB has a new command: "thread find [REGEXP]".
269 It finds the thread id whose name, target id, or thread extra info
270 matches the given regular expression.
272 * The "catch syscall" command now works on mips*-linux* targets.
274 * The -data-disassemble MI command now supports modes 2 and 3 for
275 dumping the instruction opcodes.
277 * New command line options
279 -data-directory DIR Specify DIR as the "data-directory".
280 This is mostly for testing purposes.
282 * The "maint set python auto-load on|off" command has been renamed to
283 "set auto-load-scripts on|off".
285 * GDB has a new command: "set directories".
286 It is like the "dir" command except that it replaces the
287 source path list instead of augmenting it.
289 * GDB now understands thread names.
291 On GNU/Linux, "info threads" will display the thread name as set by
292 prctl or pthread_setname_np.
294 There is also a new command, "thread name", which can be used to
295 assign a name internally for GDB to display.
298 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
299 has been integrated into GDB.
303 ** The function gdb.Write now accepts an optional keyword 'stream'.
304 This keyword, when provided, will direct the output to either
305 stdout, stderr, or GDB's logging output.
307 ** Parameters can now be be sub-classed in Python, and in particular
308 you may implement the get_set_doc and get_show_doc functions.
309 This improves how Parameter set/show documentation is processed
310 and allows for more dynamic content.
312 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
313 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
314 have an is_valid method.
316 ** Breakpoints can now be sub-classed in Python, and in particular
317 you may implement a 'stop' function that is executed each time
318 the inferior reaches that breakpoint.
320 ** New function gdb.lookup_global_symbol looks up a global symbol.
322 ** GDB values in Python are now callable if the value represents a
323 function. For example, if 'some_value' represents a function that
324 takes two integer parameters and returns a value, you can call
325 that function like so:
327 result = some_value (10,20)
329 ** Module gdb.types has been added.
330 It contains a collection of utilities for working with gdb.Types objects:
331 get_basic_type, has_field, make_enum_dict.
333 ** Module gdb.printing has been added.
334 It contains utilities for writing and registering pretty-printers.
335 New classes: PrettyPrinter, SubPrettyPrinter,
336 RegexpCollectionPrettyPrinter.
337 New function: register_pretty_printer.
339 ** New commands "info pretty-printers", "enable pretty-printer" and
340 "disable pretty-printer" have been added.
342 ** gdb.parameter("directories") is now available.
344 ** New function gdb.newest_frame returns the newest frame in the
347 ** The gdb.InferiorThread class has a new "name" attribute. This
348 holds the thread's name.
350 ** Python Support for Inferior events.
351 Python scripts can add observers to be notified of events
352 occurring in the process being debugged.
353 The following events are currently supported:
354 - gdb.events.cont Continue event.
355 - gdb.events.exited Inferior exited event.
356 - gdb.events.stop Signal received, and Breakpoint hit events.
360 ** GDB now puts template parameters in scope when debugging in an
361 instantiation. For example, if you have:
363 template<int X> int func (void) { return X; }
365 then if you step into func<5>, "print X" will show "5". This
366 feature requires proper debuginfo support from the compiler; it
367 was added to GCC 4.5.
369 ** The motion commands "next", "finish", "until", and "advance" now
370 work better when exceptions are thrown. In particular, GDB will
371 no longer lose control of the inferior; instead, the GDB will
372 stop the inferior at the point at which the exception is caught.
373 This functionality requires a change in the exception handling
374 code that was introduced in GCC 4.5.
376 * GDB now follows GCC's rules on accessing volatile objects when
377 reading or writing target state during expression evaluation.
378 One notable difference to prior behavior is that "print x = 0"
379 no longer generates a read of x; the value of the assignment is
380 now always taken directly from the value being assigned.
382 * GDB now has some support for using labels in the program's source in
383 linespecs. For instance, you can use "advance label" to continue
384 execution to a label.
386 * GDB now has support for reading and writing a new .gdb_index
387 section. This section holds a fast index of DWARF debugging
388 information and can be used to greatly speed up GDB startup and
389 operation. See the documentation for `save gdb-index' for details.
391 * The "watch" command now accepts an optional "-location" argument.
392 When used, this causes GDB to watch the memory referred to by the
393 expression. Such a watchpoint is never deleted due to it going out
396 * GDB now supports thread debugging of core dumps on GNU/Linux.
398 GDB now activates thread debugging using the libthread_db library
399 when debugging GNU/Linux core dumps, similarly to when debugging
400 live processes. As a result, when debugging a core dump file, GDB
401 is now able to display pthread_t ids of threads. For example, "info
402 threads" shows the same output as when debugging the process when it
403 was live. In earlier releases, you'd see something like this:
406 * 1 LWP 6780 main () at main.c:10
408 While now you see this:
411 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
413 It is also now possible to inspect TLS variables when debugging core
416 When debugging a core dump generated on a machine other than the one
417 used to run GDB, you may need to point GDB at the correct
418 libthread_db library with the "set libthread-db-search-path"
419 command. See the user manual for more details on this command.
421 * When natively debugging programs on PowerPC BookE processors running
422 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
423 which stop execution of the inferior whenever it executes an instruction
424 at any address within the specified range. See the "PowerPC Embedded"
425 section in the user manual for more details.
427 * New features in the GDB remote stub, GDBserver
429 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
430 and i686 LynxOS (version 5.x).
432 ** GDBserver is now supported on Blackfin Linux.
434 * New native configurations
436 ia64 HP-UX ia64-*-hpux*
440 Analog Devices, Inc. Blackfin Processor bfin-*
442 * Ada task switching is now supported on sparc-elf targets when
443 debugging a program using the Ravenscar Profile. For more information,
444 see the "Tasking Support when using the Ravenscar Profile" section
445 in the GDB user manual.
447 * Guile support was removed.
449 * New features in the GNU simulator
451 ** The --map-info flag lists all known core mappings.
453 ** CFI flashes may be simulated via the "cfi" device.
455 *** Changes in GDB 7.2
457 * Shared library support for remote targets by default
459 When GDB is configured for a generic, non-OS specific target, like
460 for example, --target=arm-eabi or one of the many *-*-elf targets,
461 GDB now queries remote stubs for loaded shared libraries using the
462 `qXfer:libraries:read' packet. Previously, shared library support
463 was always disabled for such configurations.
467 ** Argument Dependent Lookup (ADL)
469 In C++ ADL lookup directs function search to the namespaces of its
470 arguments even if the namespace has not been imported.
480 Here the compiler will search for `foo' in the namespace of 'b'
481 and find A::foo. GDB now supports this. This construct is commonly
482 used in the Standard Template Library for operators.
484 ** Improved User Defined Operator Support
486 In addition to member operators, GDB now supports lookup of operators
487 defined in a namespace and imported with a `using' directive, operators
488 defined in the global scope, operators imported implicitly from an
489 anonymous namespace, and the ADL operators mentioned in the previous
491 GDB now also supports proper overload resolution for all the previously
492 mentioned flavors of operators.
494 ** static const class members
496 Printing of static const class members that are initialized in the
497 class definition has been fixed.
499 * Windows Thread Information Block access.
501 On Windows targets, GDB now supports displaying the Windows Thread
502 Information Block (TIB) structure. This structure is visible either
503 by using the new command `info w32 thread-information-block' or, by
504 dereferencing the new convenience variable named `$_tlb', a
505 thread-specific pointer to the TIB. This feature is also supported
506 when remote debugging using GDBserver.
510 Static tracepoints are calls in the user program into a tracing
511 library. One such library is a port of the LTTng kernel tracer to
512 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
513 When debugging with GDBserver, GDB now supports combining the GDB
514 tracepoint machinery with such libraries. For example: the user can
515 use GDB to probe a static tracepoint marker (a call from the user
516 program into the tracing library) with the new "strace" command (see
517 "New commands" below). This creates a "static tracepoint" in the
518 breakpoint list, that can be manipulated with the same feature set
519 as fast and regular tracepoints. E.g., collect registers, local and
520 global variables, collect trace state variables, and define
521 tracepoint conditions. In addition, the user can collect extra
522 static tracepoint marker specific data, by collecting the new
523 $_sdata internal variable. When analyzing the trace buffer, you can
524 inspect $_sdata like any other variable available to GDB. For more
525 information, see the "Tracepoints" chapter in GDB user manual. New
526 remote packets have been defined to support static tracepoints, see
527 the "New remote packets" section below.
529 * Better reconstruction of tracepoints after disconnected tracing
531 GDB will attempt to download the original source form of tracepoint
532 definitions when starting a trace run, and then will upload these
533 upon reconnection to the target, resulting in a more accurate
534 reconstruction of the tracepoints that are in use on the target.
538 You can now exercise direct control over the ways that GDB can
539 affect your program. For instance, you can disallow the setting of
540 breakpoints, so that the program can run continuously (assuming
541 non-stop mode). In addition, the "observer" variable is available
542 to switch all of the different controls; in observer mode, GDB
543 cannot affect the target's behavior at all, which is useful for
544 tasks like diagnosing live systems in the field.
546 * The new convenience variable $_thread holds the number of the
553 Return the address of the Windows Thread Information Block of a given thread.
557 In response to several of the tracepoint packets, the target may now
558 also respond with a number of intermediate `qRelocInsn' request
559 packets before the final result packet, to have GDB handle
560 relocating an instruction to execute at a different address. This
561 is particularly useful for stubs that support fast tracepoints. GDB
562 reports support for this feature in the qSupported packet.
566 List static tracepoint markers in the target program.
570 List static tracepoint markers at a given address in the target
573 qXfer:statictrace:read
575 Read the static trace data collected (by a `collect $_sdata'
576 tracepoint action). The remote stub reports support for this packet
577 to gdb's qSupported query.
581 Send the current settings of GDB's permission flags.
585 Send part of the source (textual) form of a tracepoint definition,
586 which includes location, conditional, and action list.
588 * The source command now accepts a -s option to force searching for the
589 script in the source search path even if the script name specifies
592 * New features in the GDB remote stub, GDBserver
594 - GDBserver now support tracepoints (including fast tracepoints, and
595 static tracepoints). The feature is currently supported by the
596 i386-linux and amd64-linux builds. See the "Tracepoints support
597 in gdbserver" section in the manual for more information.
599 GDBserver JIT compiles the tracepoint's conditional agent
600 expression bytecode into native code whenever possible for low
601 overhead dynamic tracepoints conditionals. For such tracepoints,
602 an expression that examines program state is evaluated when the
603 tracepoint is reached, in order to determine whether to capture
604 trace data. If the condition is simple and false, processing the
605 tracepoint finishes very quickly and no data is gathered.
607 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
608 for static tracepoints support.
610 - GDBserver now supports x86_64 Windows 64-bit debugging.
612 * GDB now sends xmlRegisters= in qSupported packet to indicate that
613 it understands register description.
615 * The --batch flag now disables pagination and queries.
617 * X86 general purpose registers
619 GDB now supports reading/writing byte, word and double-word x86
620 general purpose registers directly. This means you can use, say,
621 $ah or $ax to refer, respectively, to the byte register AH and
622 16-bit word register AX that are actually portions of the 32-bit
623 register EAX or 64-bit register RAX.
625 * The `commands' command now accepts a range of breakpoints to modify.
626 A plain `commands' following a command that creates multiple
627 breakpoints affects all the breakpoints set by that command. This
628 applies to breakpoints set by `rbreak', and also applies when a
629 single `break' command creates multiple breakpoints (e.g.,
630 breakpoints on overloaded c++ functions).
632 * The `rbreak' command now accepts a filename specification as part of
633 its argument, limiting the functions selected by the regex to those
634 in the specified file.
636 * Support for remote debugging Windows and SymbianOS shared libraries
637 from Unix hosts has been improved. Non Windows GDB builds now can
638 understand target reported file names that follow MS-DOS based file
639 system semantics, such as file names that include drive letters and
640 use the backslash character as directory separator. This makes it
641 possible to transparently use the "set sysroot" and "set
642 solib-search-path" on Unix hosts to point as host copies of the
643 target's shared libraries. See the new command "set
644 target-file-system-kind" described below, and the "Commands to
645 specify files" section in the user manual for more information.
649 eval template, expressions...
650 Convert the values of one or more expressions under the control
651 of the string template to a command line, and call it.
653 set target-file-system-kind unix|dos-based|auto
654 show target-file-system-kind
655 Set or show the assumed file system kind for target reported file
658 save breakpoints <filename>
659 Save all current breakpoint definitions to a file suitable for use
660 in a later debugging session. To read the saved breakpoint
661 definitions, use the `source' command.
663 `save tracepoints' is a new alias for `save-tracepoints'. The latter
666 info static-tracepoint-markers
667 Display information about static tracepoint markers in the target.
669 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
670 Define a static tracepoint by probing a marker at the given
671 function, line, address, or marker ID.
675 Enable and disable observer mode.
677 set may-write-registers on|off
678 set may-write-memory on|off
679 set may-insert-breakpoints on|off
680 set may-insert-tracepoints on|off
681 set may-insert-fast-tracepoints on|off
682 set may-interrupt on|off
683 Set individual permissions for GDB effects on the target. Note that
684 some of these settings can have undesirable or surprising
685 consequences, particularly when changed in the middle of a session.
686 For instance, disabling the writing of memory can prevent
687 breakpoints from being inserted, cause single-stepping to fail, or
688 even crash your program, if you disable after breakpoints have been
689 inserted. However, GDB should not crash.
691 set record memory-query on|off
692 show record memory-query
693 Control whether to stop the inferior if memory changes caused
694 by an instruction cannot be recorded.
699 The disassemble command now supports "start,+length" form of two arguments.
703 ** GDB now provides a new directory location, called the python directory,
704 where Python scripts written for GDB can be installed. The location
705 of that directory is <data-directory>/python, where <data-directory>
706 is the GDB data directory. For more details, see section `Scripting
707 GDB using Python' in the manual.
709 ** The GDB Python API now has access to breakpoints, symbols, symbol
710 tables, program spaces, inferiors, threads and frame's code blocks.
711 Additionally, GDB Parameters can now be created from the API, and
712 manipulated via set/show in the CLI.
714 ** New functions gdb.target_charset, gdb.target_wide_charset,
715 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
717 ** New exception gdb.GdbError.
719 ** Pretty-printers are now also looked up in the current program space.
721 ** Pretty-printers can now be individually enabled and disabled.
723 ** GDB now looks for names of Python scripts to auto-load in a
724 special section named `.debug_gdb_scripts', in addition to looking
725 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
727 * Tracepoint actions were unified with breakpoint commands. In particular,
728 there are no longer differences in "info break" output for breakpoints and
729 tracepoints and the "commands" command can be used for both tracepoints and
734 ARM Symbian arm*-*-symbianelf*
736 * D language support.
737 GDB now supports debugging programs written in the D programming
740 * GDB now supports the extended ptrace interface for PowerPC which is
741 available since Linux kernel version 2.6.34. This automatically enables
742 any hardware breakpoints and additional hardware watchpoints available in
743 the processor. The old ptrace interface exposes just one hardware
744 watchpoint and no hardware breakpoints.
746 * GDB is now able to use the Data Value Compare (DVC) register available on
747 embedded PowerPC processors to implement in hardware simple watchpoint
748 conditions of the form:
750 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
752 This works in native GDB running on Linux kernels with the extended ptrace
753 interface mentioned above.
755 *** Changes in GDB 7.1
761 GDB now supports importing of namespaces in C++. This enables the
762 user to inspect variables from imported namespaces. Support for
763 namepace aliasing has also been added. So, if a namespace is
764 aliased in the current scope (e.g. namepace C=A; ) the user can
765 print variables using the alias (e.g. (gdb) print C::x).
769 All known bugs relating to the printing of virtual base class were
770 fixed. It is now possible to call overloaded static methods using a
775 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
776 and reinterpret_cast<> are now handled by the C++ expression parser.
780 Xilinx MicroBlaze microblaze-*-*
785 Xilinx MicroBlaze microblaze
788 * Multi-program debugging.
790 GDB now has support for multi-program (a.k.a. multi-executable or
791 multi-exec) debugging. This allows for debugging multiple inferiors
792 simultaneously each running a different program under the same GDB
793 session. See "Debugging Multiple Inferiors and Programs" in the
794 manual for more information. This implied some user visible changes
795 in the multi-inferior support. For example, "info inferiors" now
796 lists inferiors that are not running yet or that have exited
797 already. See also "New commands" and "New options" below.
799 * New tracing features
801 GDB's tracepoint facility now includes several new features:
803 ** Trace state variables
805 GDB tracepoints now include support for trace state variables, which
806 are variables managed by the target agent during a tracing
807 experiment. They are useful for tracepoints that trigger each
808 other, so for instance one tracepoint can count hits in a variable,
809 and then a second tracepoint has a condition that is true when the
810 count reaches a particular value. Trace state variables share the
811 $-syntax of GDB convenience variables, and can appear in both
812 tracepoint actions and condition expressions. Use the "tvariable"
813 command to create, and "info tvariables" to view; see "Trace State
814 Variables" in the manual for more detail.
818 GDB now includes an option for defining fast tracepoints, which
819 targets may implement more efficiently, such as by installing a jump
820 into the target agent rather than a trap instruction. The resulting
821 speedup can be by two orders of magnitude or more, although the
822 tradeoff is that some program locations on some target architectures
823 might not allow fast tracepoint installation, for instance if the
824 instruction to be replaced is shorter than the jump. To request a
825 fast tracepoint, use the "ftrace" command, with syntax identical to
826 the regular trace command.
828 ** Disconnected tracing
830 It is now possible to detach GDB from the target while it is running
831 a trace experiment, then reconnect later to see how the experiment
832 is going. In addition, a new variable disconnected-tracing lets you
833 tell the target agent whether to continue running a trace if the
834 connection is lost unexpectedly.
838 GDB now has the ability to save the trace buffer into a file, and
839 then use that file as a target, similarly to you can do with
840 corefiles. You can select trace frames, print data that was
841 collected in them, and use tstatus to display the state of the
842 tracing run at the moment that it was saved. To create a trace
843 file, use "tsave <filename>", and to use it, do "target tfile
846 ** Circular trace buffer
848 You can ask the target agent to handle the trace buffer as a
849 circular buffer, discarding the oldest trace frames to make room for
850 newer ones, by setting circular-trace-buffer to on. This feature may
851 not be available for all target agents.
856 The disassemble command, when invoked with two arguments, now requires
857 the arguments to be comma-separated.
860 The info variables command now displays variable definitions. Files
861 which only declare a variable are not shown.
864 The source command is now capable of sourcing Python scripts.
865 This feature is dependent on the debugger being build with Python
868 Related to this enhancement is also the introduction of a new command
869 "set script-extension" (see below).
871 * New commands (for set/show, see "New options" below)
873 record save [<FILENAME>]
874 Save a file (in core file format) containing the process record
875 execution log for replay debugging at a later time.
877 record restore <FILENAME>
878 Restore the process record execution log that was saved at an
879 earlier time, for replay debugging.
881 add-inferior [-copies <N>] [-exec <FILENAME>]
884 clone-inferior [-copies <N>] [ID]
885 Make a new inferior ready to execute the same program another
891 maint info program-spaces
892 List the program spaces loaded into GDB.
894 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
895 show remote interrupt-sequence
896 Allow the user to select one of ^C, a BREAK signal or BREAK-g
897 as the sequence to the remote target in order to interrupt the execution.
898 Ctrl-C is a default. Some system prefers BREAK which is high level of
899 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
900 Magic SysRq g. It is BREAK signal and character 'g'.
902 set remote interrupt-on-connect [on | off]
903 show remote interrupt-on-connect
904 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
905 remote target when gdb connects to it. This is needed when you debug
908 set remotebreak [on | off]
910 Deprecated. Use "set/show remote interrupt-sequence" instead.
912 tvariable $NAME [ = EXP ]
913 Create or modify a trace state variable.
916 List trace state variables and their values.
918 delete tvariable $NAME ...
919 Delete one or more trace state variables.
922 Evaluate the given expressions without collecting anything into the
923 trace buffer. (Valid in tracepoint actions only.)
925 ftrace FN / FILE:LINE / *ADDR
926 Define a fast tracepoint at the given function, line, or address.
928 * New expression syntax
930 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
931 GDB now parses 0b101010 identically with 42.
935 set follow-exec-mode new|same
936 show follow-exec-mode
937 Control whether GDB reuses the same inferior across an exec call or
938 creates a new one. This is useful to be able to restart the old
939 executable after the inferior having done an exec call.
941 set default-collect EXPR, ...
943 Define a list of expressions to be collected at each tracepoint.
944 This is a useful way to ensure essential items are not overlooked,
945 such as registers or a critical global variable.
947 set disconnected-tracing
948 show disconnected-tracing
949 If set to 1, the target is instructed to continue tracing if it
950 loses its connection to GDB. If 0, the target is to stop tracing
953 set circular-trace-buffer
954 show circular-trace-buffer
955 If set to on, the target is instructed to use a circular trace buffer
956 and discard the oldest trace frames instead of stopping the trace due
957 to a full trace buffer. If set to off, the trace stops when the buffer
958 fills up. Some targets may not support this.
960 set script-extension off|soft|strict
961 show script-extension
962 If set to "off", the debugger does not perform any script language
963 recognition, and all sourced files are assumed to be GDB scripts.
964 If set to "soft" (the default), files are sourced according to
965 filename extension, falling back to GDB scripts if the first
967 If set to "strict", files are sourced according to filename extension.
969 set ada trust-PAD-over-XVS on|off
970 show ada trust-PAD-over-XVS
971 If off, activate a workaround against a bug in the debugging information
972 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
973 the GCC sources for more information about the GNAT encoding and
974 PAD types in particular). It is always safe to set this option to
975 off, but this introduces a slight performance penalty. The default
978 * Python API Improvements
980 ** GDB provides the new class gdb.LazyString. This is useful in
981 some pretty-printing cases. The new method gdb.Value.lazy_string
982 provides a simple way to create objects of this type.
984 ** The fields returned by gdb.Type.fields now have an
985 `is_base_class' attribute.
987 ** The new method gdb.Type.range returns the range of an array type.
989 ** The new method gdb.parse_and_eval can be used to parse and
990 evaluate an expression.
995 Define a trace state variable.
998 Get the current value of a trace state variable.
1001 Set desired tracing behavior upon disconnection.
1004 Set the trace buffer to be linear or circular.
1007 Get data about the tracepoints currently in use.
1011 Process record now works correctly with hardware watchpoints.
1013 Multiple bug fixes have been made to the mips-irix port, making it
1014 much more reliable. In particular:
1015 - Debugging threaded applications is now possible again. Previously,
1016 GDB would hang while starting the program, or while waiting for
1017 the program to stop at a breakpoint.
1018 - Attaching to a running process no longer hangs.
1019 - An error occurring while loading a core file has been fixed.
1020 - Changing the value of the PC register now works again. This fixes
1021 problems observed when using the "jump" command, or when calling
1022 a function from GDB, or even when assigning a new value to $pc.
1023 - With the "finish" and "return" commands, the return value for functions
1024 returning a small array is now correctly printed.
1025 - It is now possible to break on shared library code which gets executed
1026 during a shared library init phase (code executed while executing
1027 their .init section). Previously, the breakpoint would have no effect.
1028 - GDB is now able to backtrace through the signal handler for
1029 non-threaded programs.
1031 PIE (Position Independent Executable) programs debugging is now supported.
1032 This includes debugging execution of PIC (Position Independent Code) shared
1033 libraries although for that, it should be possible to run such libraries as an
1036 *** Changes in GDB 7.0
1038 * GDB now has an interface for JIT compilation. Applications that
1039 dynamically generate code can create symbol files in memory and register
1040 them with GDB. For users, the feature should work transparently, and
1041 for JIT developers, the interface is documented in the GDB manual in the
1042 "JIT Compilation Interface" chapter.
1044 * Tracepoints may now be conditional. The syntax is as for
1045 breakpoints; either an "if" clause appended to the "trace" command,
1046 or the "condition" command is available. GDB sends the condition to
1047 the target for evaluation using the same bytecode format as is used
1048 for tracepoint actions.
1050 * The disassemble command now supports: an optional /r modifier, print the
1051 raw instructions in hex as well as in symbolic form, and an optional /m
1052 modifier to print mixed source+assembly.
1054 * Process record and replay
1056 In a architecture environment that supports ``process record and
1057 replay'', ``process record and replay'' target can record a log of
1058 the process execution, and replay it with both forward and reverse
1061 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1062 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1063 set execution-direction {forward|reverse}, for targets that support
1066 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1067 feature is available with a native GDB running on kernel version
1070 * GDB now has support for multi-byte and wide character sets on the
1071 target. Strings whose character type is wchar_t, char16_t, or
1072 char32_t are now correctly printed. GDB supports wide- and unicode-
1073 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1074 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1075 `printf'. This feature requires iconv to work properly; if your
1076 system does not have a working iconv, GDB can use GNU libiconv. See
1077 the installation instructions for more information.
1079 * GDB now supports automatic retrieval of shared library files from
1080 remote targets. To use this feature, specify a system root that begins
1081 with the `remote:' prefix, either via the `set sysroot' command or via
1082 the `--with-sysroot' configure-time option.
1084 * "info sharedlibrary" now takes an optional regex of libraries to show,
1085 and it now reports if a shared library has no debugging information.
1087 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1088 now complete on file names.
1090 * When completing in expressions, gdb will attempt to limit
1091 completions to allowable structure or union fields, where appropriate.
1092 For instance, consider:
1094 # struct example { int f1; double f2; };
1095 # struct example variable;
1098 If the user types TAB at the end of this command line, the available
1099 completions will be "f1" and "f2".
1101 * Inlined functions are now supported. They show up in backtraces, and
1102 the "step", "next", and "finish" commands handle them automatically.
1104 * GDB now supports the token-splicing (##) and stringification (#)
1105 operators when expanding macros. It also supports variable-arity
1108 * GDB now supports inspecting extra signal information, exported by
1109 the new $_siginfo convenience variable. The feature is currently
1110 implemented on linux ARM, i386 and amd64.
1112 * GDB can now display the VFP floating point registers and NEON vector
1113 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1114 can provide these registers (requires Linux 2.6.30 or later). Remote
1115 and simulator targets may also provide them.
1117 * New remote packets
1120 Search memory for a sequence of bytes.
1123 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1124 operation over reliable transport links. Use of this packet is
1125 controlled by the `set remote noack-packet' command.
1128 Kill the process with the specified process ID. Use this in preference
1129 to `k' when multiprocess protocol extensions are supported.
1132 Obtains additional operating system information
1136 Read or write additional signal information.
1138 * Removed remote protocol undocumented extension
1140 An undocumented extension to the remote protocol's `S' stop reply
1141 packet that permited the stub to pass a process id was removed.
1142 Remote servers should use the `T' stop reply packet instead.
1144 * GDB now supports multiple function calling conventions according to the
1145 DWARF-2 DW_AT_calling_convention function attribute.
1147 * The SH target utilizes the aforementioned change to distinguish between gcc
1148 and Renesas calling convention. It also adds the new CLI commands
1149 `set/show sh calling-convention'.
1151 * GDB can now read compressed debug sections, as produced by GNU gold
1152 with the --compress-debug-sections=zlib flag.
1154 * 64-bit core files are now supported on AIX.
1156 * Thread switching is now supported on Tru64.
1158 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1159 which will be allocated using malloc later in program execution.
1161 * The qXfer:libraries:read remote procotol packet now allows passing a
1162 list of section offsets.
1164 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1165 conditions handling signals delivered during attach or thread creation
1166 have also been fixed.
1168 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1169 From the user's standpoint, all unqualified instances of True and False
1170 are treated as the standard definitions, regardless of context.
1172 * GDB now parses C++ symbol and type names more flexibly. For
1175 template<typename T> class C { };
1178 GDB will now correctly handle all of:
1180 ptype C<char const *>
1181 ptype C<char const*>
1182 ptype C<const char *>
1183 ptype C<const char*>
1185 * New features in the GDB remote stub, gdbserver
1187 - The "--wrapper" command-line argument tells gdbserver to use a
1188 wrapper program to launch programs for debugging.
1190 - On PowerPC and S/390 targets, it is now possible to use a single
1191 gdbserver executable to debug both 32-bit and 64-bit programs.
1192 (This requires gdbserver itself to be built as a 64-bit executable.)
1194 - gdbserver uses the new noack protocol mode for TCP connections to
1195 reduce communications latency, if also supported and enabled in GDB.
1197 - Support for the sparc64-linux-gnu target is now included in
1200 - The amd64-linux build of gdbserver now supports debugging both
1201 32-bit and 64-bit programs.
1203 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1204 now support hardware watchpoints, and will use them automatically
1209 GDB now has support for scripting using Python. Whether this is
1210 available is determined at configure time.
1212 New GDB commands can now be written in Python.
1214 * Ada tasking support
1216 Ada tasks can now be inspected in GDB. The following commands have
1220 Print the list of Ada tasks.
1222 Print detailed information about task number N.
1224 Print the task number of the current task.
1226 Switch the context of debugging to task number N.
1228 * Support for user-defined prefixed commands. The "define" command can
1229 add new commands to existing prefixes, e.g. "target".
1231 * Multi-inferior, multi-process debugging.
1233 GDB now has generalized support for multi-inferior debugging. See
1234 "Debugging Multiple Inferiors" in the manual for more information.
1235 Although availability still depends on target support, the command
1236 set is more uniform now. The GNU/Linux specific multi-forks support
1237 has been migrated to this new framework. This implied some user
1238 visible changes; see "New commands" and also "Removed commands"
1241 * Target descriptions can now describe the target OS ABI. See the
1242 "Target Description Format" section in the user manual for more
1245 * Target descriptions can now describe "compatible" architectures
1246 to indicate that the target can execute applications for a different
1247 architecture in addition to those for the main target architecture.
1248 See the "Target Description Format" section in the user manual for
1251 * Multi-architecture debugging.
1253 GDB now includes general supports for debugging applications on
1254 hybrid systems that use more than one single processor architecture
1255 at the same time. Each such hybrid architecture still requires
1256 specific support to be added. The only hybrid architecture supported
1257 in this version of GDB is the Cell Broadband Engine.
1259 * GDB now supports integrated debugging of Cell/B.E. applications that
1260 use both the PPU and SPU architectures. To enable support for hybrid
1261 Cell/B.E. debugging, you need to configure GDB to support both the
1262 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1263 --enable-targets configure option.
1265 * Non-stop mode debugging.
1267 For some targets, GDB now supports an optional mode of operation in
1268 which you can examine stopped threads while other threads continue
1269 to execute freely. This is referred to as non-stop mode, with the
1270 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1271 section in the user manual for more information.
1273 To be able to support remote non-stop debugging, a remote stub needs
1274 to implement the non-stop mode remote protocol extensions, as
1275 described in the "Remote Non-Stop" section of the user manual. The
1276 GDB remote stub, gdbserver, has been adjusted to support these
1277 extensions on linux targets.
1279 * New commands (for set/show, see "New options" below)
1281 catch syscall [NAME(S) | NUMBER(S)]
1282 Catch system calls. Arguments, which should be names of system
1283 calls or their numbers, mean catch only those syscalls. Without
1284 arguments, every syscall will be caught. When the inferior issues
1285 any of the specified syscalls, GDB will stop and announce the system
1286 call, both when it is called and when its call returns. This
1287 feature is currently available with a native GDB running on the
1288 Linux Kernel, under the following architectures: x86, x86_64,
1289 PowerPC and PowerPC64.
1291 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1293 Search memory for a sequence of bytes.
1295 maint set python print-stack
1296 maint show python print-stack
1297 Show a stack trace when an error is encountered in a Python script.
1300 Invoke CODE by passing it to the Python interpreter.
1305 These allow macros to be defined, undefined, and listed
1309 Show operating system information about processes.
1312 List the inferiors currently under GDB's control.
1315 Switch focus to inferior number NUM.
1318 Detach from inferior number NUM.
1321 Kill inferior number NUM.
1325 set spu stop-on-load
1326 show spu stop-on-load
1327 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1329 set spu auto-flush-cache
1330 show spu auto-flush-cache
1331 Control whether to automatically flush the software-managed cache
1332 during Cell/B.E. debugging.
1334 set sh calling-convention
1335 show sh calling-convention
1336 Control the calling convention used when calling SH target functions.
1339 show debug timestamp
1340 Control display of timestamps with GDB debugging output.
1342 set disassemble-next-line
1343 show disassemble-next-line
1344 Control display of disassembled source lines or instructions when
1347 set remote noack-packet
1348 show remote noack-packet
1349 Set/show the use of remote protocol QStartNoAckMode packet. See above
1350 under "New remote packets."
1352 set remote query-attached-packet
1353 show remote query-attached-packet
1354 Control use of remote protocol `qAttached' (query-attached) packet.
1356 set remote read-siginfo-object
1357 show remote read-siginfo-object
1358 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1361 set remote write-siginfo-object
1362 show remote write-siginfo-object
1363 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1366 set remote reverse-continue
1367 show remote reverse-continue
1368 Control use of remote protocol 'bc' (reverse-continue) packet.
1370 set remote reverse-step
1371 show remote reverse-step
1372 Control use of remote protocol 'bs' (reverse-step) packet.
1374 set displaced-stepping
1375 show displaced-stepping
1376 Control displaced stepping mode. Displaced stepping is a way to
1377 single-step over breakpoints without removing them from the debuggee.
1378 Also known as "out-of-line single-stepping".
1381 show debug displaced
1382 Control display of debugging info for displaced stepping.
1384 maint set internal-error
1385 maint show internal-error
1386 Control what GDB does when an internal error is detected.
1388 maint set internal-warning
1389 maint show internal-warning
1390 Control what GDB does when an internal warning is detected.
1395 Use a wrapper program to launch programs for debugging.
1397 set multiple-symbols (all|ask|cancel)
1398 show multiple-symbols
1399 The value of this variable can be changed to adjust the debugger behavior
1400 when an expression or a breakpoint location contains an ambiguous symbol
1401 name (an overloaded function name, for instance).
1403 set breakpoint always-inserted
1404 show breakpoint always-inserted
1405 Keep breakpoints always inserted in the target, as opposed to inserting
1406 them when resuming the target, and removing them when the target stops.
1407 This option can improve debugger performance on slow remote targets.
1409 set arm fallback-mode (arm|thumb|auto)
1410 show arm fallback-mode
1411 set arm force-mode (arm|thumb|auto)
1413 These commands control how ARM GDB determines whether instructions
1414 are ARM or Thumb. The default for both settings is auto, which uses
1415 the current CPSR value for instructions without symbols; previous
1416 versions of GDB behaved as if "set arm fallback-mode arm".
1418 set disable-randomization
1419 show disable-randomization
1420 Standalone programs run with the virtual address space randomization enabled
1421 by default on some platforms. This option keeps the addresses stable across
1422 multiple debugging sessions.
1426 Control whether other threads are stopped or not when some thread hits
1431 Requests that asynchronous execution is enabled in the target, if available.
1432 In this case, it's possible to resume target in the background, and interact
1433 with GDB while the target is running. "show target-async" displays the
1434 current state of asynchronous execution of the target.
1436 set target-wide-charset
1437 show target-wide-charset
1438 The target-wide-charset is the name of the character set that GDB
1439 uses when printing characters whose type is wchar_t.
1441 set tcp auto-retry (on|off)
1443 set tcp connect-timeout
1444 show tcp connect-timeout
1445 These commands allow GDB to retry failed TCP connections to a remote stub
1446 with a specified timeout period; this is useful if the stub is launched
1447 in parallel with GDB but may not be ready to accept connections immediately.
1449 set libthread-db-search-path
1450 show libthread-db-search-path
1451 Control list of directories which GDB will search for appropriate
1454 set schedule-multiple (on|off)
1455 show schedule-multiple
1456 Allow GDB to resume all threads of all processes or only threads of
1457 the current process.
1461 Use more aggressive caching for accesses to the stack. This improves
1462 performance of remote debugging (particularly backtraces) without
1463 affecting correctness.
1465 set interactive-mode (on|off|auto)
1466 show interactive-mode
1467 Control whether GDB runs in interactive mode (on) or not (off).
1468 When in interactive mode, GDB waits for the user to answer all
1469 queries. Otherwise, GDB does not wait and assumes the default
1470 answer. When set to auto (the default), GDB determines which
1471 mode to use based on the stdin settings.
1476 For program forks, this is replaced by the new more generic `info
1477 inferiors' command. To list checkpoints, you can still use the
1478 `info checkpoints' command, which was an alias for the `info forks'
1482 Replaced by the new `inferior' command. To switch between
1483 checkpoints, you can still use the `restart' command, which was an
1484 alias for the `fork' command.
1487 This is removed, since some targets don't have a notion of
1488 processes. To switch between processes, you can still use the
1489 `inferior' command using GDB's own inferior number.
1492 For program forks, this is replaced by the new more generic `kill
1493 inferior' command. To delete a checkpoint, you can still use the
1494 `delete checkpoint' command, which was an alias for the `delete
1498 For program forks, this is replaced by the new more generic `detach
1499 inferior' command. To detach a checkpoint, you can still use the
1500 `detach checkpoint' command, which was an alias for the `detach
1503 * New native configurations
1505 x86/x86_64 Darwin i[34567]86-*-darwin*
1507 x86_64 MinGW x86_64-*-mingw*
1511 Lattice Mico32 lm32-*
1512 x86 DICOS i[34567]86-*-dicos*
1513 x86_64 DICOS x86_64-*-dicos*
1516 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1517 (mingw32ce) debugging.
1523 These commands were actually not implemented on any target.
1525 *** Changes in GDB 6.8
1527 * New native configurations
1529 NetBSD/hppa hppa*-*netbsd*
1530 Xtensa GNU/Linux xtensa*-*-linux*
1534 NetBSD/hppa hppa*-*-netbsd*
1535 Xtensa GNU/Lunux xtensa*-*-linux*
1537 * Change in command line behavior -- corefiles vs. process ids.
1539 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1540 attaching to process NUMBER fails, GDB no longer attempts to open a
1541 core file named NUMBER. Attaching to a program using the -c option
1542 is no longer supported. Instead, use the '-p' or '--pid' options.
1544 * GDB can now be built as a native debugger for debugging Windows x86
1545 (mingw32) Portable Executable (PE) programs.
1547 * Pending breakpoints no longer change their number when their address
1550 * GDB now supports breakpoints with multiple locations,
1551 including breakpoints on C++ constructors, inside C++ templates,
1552 and in inlined functions.
1554 * GDB's ability to debug optimized code has been improved. GDB more
1555 accurately identifies function bodies and lexical blocks that occupy
1556 more than one contiguous range of addresses.
1558 * Target descriptions can now describe registers for PowerPC.
1560 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1561 registers on PowerPC targets.
1563 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1564 targets even when the libthread_db library is not available.
1566 * The GDB remote stub, gdbserver, now supports the new file transfer
1567 commands (remote put, remote get, and remote delete).
1569 * The GDB remote stub, gdbserver, now supports run and attach in
1570 extended-remote mode.
1572 * hppa*64*-*-hpux11* target broken
1573 The debugger is unable to start a program and fails with the following
1574 error: "Error trying to get information about dynamic linker".
1575 The gdb-6.7 release is also affected.
1577 * GDB now supports the --enable-targets= configure option to allow
1578 building a single GDB executable that supports multiple remote
1579 target architectures.
1581 * GDB now supports debugging C and C++ programs which use the
1582 Decimal Floating Point extension. In addition, the PowerPC target
1583 now has a set of pseudo-registers to inspect decimal float values
1584 stored in two consecutive float registers.
1586 * The -break-insert MI command can optionally create pending
1589 * Improved support for debugging Ada
1590 Many improvements to the Ada language support have been made. These
1592 - Better support for Ada2005 interface types
1593 - Improved handling of arrays and slices in general
1594 - Better support for Taft-amendment types
1595 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1597 - Improved command completion in Ada
1600 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1605 set print frame-arguments (all|scalars|none)
1606 show print frame-arguments
1607 The value of this variable can be changed to control which argument
1608 values should be printed by the debugger when displaying a frame.
1613 Transfer files to and from a remote target, and delete remote files.
1620 Transfer files to and from a remote target, and delete remote files.
1622 * New remote packets
1629 Open, close, read, write, and delete files on the remote system.
1632 Attach to an existing process on the remote system, in extended-remote
1636 Run a new process on the remote system, in extended-remote mode.
1638 *** Changes in GDB 6.7
1640 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1641 bfd, libiberty and opcodes, as revealed by static analysis donated by
1642 Coverity, Inc. (http://scan.coverity.com).
1644 * When looking up multiply-defined global symbols, GDB will now prefer the
1645 symbol definition in the current shared library if it was built using the
1646 -Bsymbolic linker option.
1648 * When the Text User Interface (TUI) is not configured, GDB will now
1649 recognize the -tui command-line option and print a message that the TUI
1652 * The GDB remote stub, gdbserver, now has lower overhead for high
1653 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1655 * GDB for MIPS targets now autodetects whether a remote target provides
1656 32-bit or 64-bit register values.
1658 * Support for C++ member pointers has been improved.
1660 * GDB now understands XML target descriptions, which specify the
1661 target's overall architecture. GDB can read a description from
1662 a local file or over the remote serial protocol.
1664 * Vectors of single-byte data use a new integer type which is not
1665 automatically displayed as character or string data.
1667 * The /s format now works with the print command. It displays
1668 arrays of single-byte integers and pointers to single-byte integers
1671 * Target descriptions can now describe target-specific registers,
1672 for architectures which have implemented the support (currently
1673 only ARM, M68K, and MIPS).
1675 * GDB and the GDB remote stub, gdbserver, now support the XScale
1678 * The GDB remote stub, gdbserver, has been updated to support
1679 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1680 has been rewritten to use the standard GDB remote protocol.
1682 * GDB can now step into C++ functions which are called through thunks.
1684 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1686 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1687 layout. It also supports a TextSeg= and DataSeg= response when only
1688 segment base addresses (rather than offsets) are available.
1690 * The /i format now outputs any trailing branch delay slot instructions
1691 immediately following the last instruction within the count specified.
1693 * The GDB remote protocol "T" stop reply packet now supports a
1694 "library" response. Combined with the new "qXfer:libraries:read"
1695 packet, this response allows GDB to debug shared libraries on targets
1696 where the operating system manages the list of loaded libraries (e.g.
1697 Windows and SymbianOS).
1699 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1700 (DLLs) on Windows and Windows CE targets.
1702 * GDB now supports a faster verification that a .debug file matches its binary
1703 according to its build-id signature, if the signature is present.
1709 Enable or disable hardware flow control (RTS/CTS) on the serial port
1710 when debugging using remote targets.
1712 set mem inaccessible-by-default
1713 show mem inaccessible-by-default
1714 If the target supplies a memory map, for instance via the remote
1715 protocol's "qXfer:memory-map:read" packet, setting this variable
1716 prevents GDB from accessing memory outside the memory map. This
1717 is useful for targets with memory mapped registers or which react
1718 badly to accesses of unmapped address space.
1720 set breakpoint auto-hw
1721 show breakpoint auto-hw
1722 If the target supplies a memory map, for instance via the remote
1723 protocol's "qXfer:memory-map:read" packet, setting this variable
1724 lets GDB use hardware breakpoints automatically for memory regions
1725 where it can not use software breakpoints. This covers both the
1726 "break" command and internal breakpoints used for other commands
1727 including "next" and "finish".
1730 catch exception unhandled
1731 Stop the program execution when Ada exceptions are raised.
1734 Stop the program execution when an Ada assertion failed.
1738 Set an alternate system root for target files. This is a more
1739 general version of "set solib-absolute-prefix", which is now
1740 an alias to "set sysroot".
1743 Provide extended SPU facility status information. This set of
1744 commands is available only when debugging the Cell/B.E. SPU
1747 * New native configurations
1749 OpenBSD/sh sh*-*openbsd*
1752 unset tdesc filename
1754 Use the specified local file as an XML target description, and do
1755 not query the target for its built-in description.
1759 OpenBSD/sh sh*-*-openbsd*
1760 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1761 Toshiba Media Processor mep-elf
1763 * New remote packets
1766 Ignore the specified signals; pass them directly to the debugged program
1767 without stopping other threads or reporting them to GDB.
1769 qXfer:features:read:
1770 Read an XML target description from the target, which describes its
1775 Read or write contents of an spufs file on the target system. These
1776 packets are available only on the Cell/B.E. SPU architecture.
1778 qXfer:libraries:read:
1779 Report the loaded shared libraries. Combined with new "T" packet
1780 response, this packet allows GDB to debug shared libraries on
1781 targets where the operating system manages the list of loaded
1782 libraries (e.g. Windows and SymbianOS).
1786 Support for these obsolete configurations has been removed.
1794 i[34567]86-*-lynxos*
1795 i[34567]86-*-netware*
1796 i[34567]86-*-sco3.2v5*
1797 i[34567]86-*-sco3.2v4*
1799 i[34567]86-*-sysv4.2*
1802 i[34567]86-*-unixware2*
1803 i[34567]86-*-unixware*
1812 * Other removed features
1819 Various m68k-only ROM monitors.
1826 Various Renesas ROM monitors and debugging interfaces for SH and
1831 Support for a Macraigor serial interface to on-chip debugging.
1832 GDB does not directly support the newer parallel or USB
1837 A debug information format. The predecessor to DWARF 2 and
1838 DWARF 3, which are still supported.
1840 Support for the HP aCC compiler on HP-UX/PA-RISC
1842 SOM-encapsulated symbolic debugging information, automatic
1843 invocation of pxdb, and the aCC custom C++ ABI. This does not
1844 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1845 with aCC can still be debugged on an assembly level.
1847 MIPS ".pdr" sections
1849 A MIPS-specific format used to describe stack frame layout
1850 in debugging information.
1854 GDB could work with an older version of Guile to debug
1855 the interpreter and Scheme programs running in it.
1857 set mips stack-arg-size
1858 set mips saved-gpreg-size
1860 Use "set mips abi" to control parameter passing for MIPS.
1862 *** Changes in GDB 6.6
1867 Cell Broadband Engine SPU spu-elf
1869 * GDB can now be configured as a cross-debugger targeting native Windows
1870 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1871 running on a Windows system over TCP/IP to debug Windows programs.
1873 * The GDB remote stub, gdbserver, has been updated to support Windows and
1874 Cygwin debugging. Both single-threaded and multi-threaded programs are
1877 * The "set trust-readonly-sections" command works again. This command was
1878 broken in GDB 6.3, 6.4, and 6.5.
1880 * The "load" command now supports writing to flash memory, if the remote
1881 stub provides the required support.
1883 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1884 longer requires symbolic debug information (e.g. DWARF-2).
1889 unset substitute-path
1890 show substitute-path
1891 Manage a list of substitution rules that GDB uses to rewrite the name
1892 of the directories where the sources are located. This can be useful
1893 for instance when the sources were moved to a different location
1894 between compilation and debugging.
1898 Print each CLI command as it is executed. Each command is prefixed with
1899 a number of `+' symbols representing the nesting depth.
1900 The source command now has a `-v' option to enable the same feature.
1904 The ARM Demon monitor support (RDP protocol, "target rdp").
1906 Kernel Object Display, an embedded debugging feature which only worked with
1907 an obsolete version of Cisco IOS.
1909 The 'set download-write-size' and 'show download-write-size' commands.
1911 * New remote packets
1914 Tell a stub about GDB client features, and request remote target features.
1915 The first feature implemented is PacketSize, which allows the target to
1916 specify the size of packets it can handle - to minimize the number of
1917 packets required and improve performance when connected to a remote
1921 Fetch an OS auxilliary vector from the remote stub. This packet is a
1922 more efficient replacement for qPart:auxv:read.
1924 qXfer:memory-map:read:
1925 Fetch a memory map from the remote stub, including information about
1926 RAM, ROM, and flash memory devices.
1931 Erase and program a flash memory device.
1933 * Removed remote packets
1936 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1937 used it, and only gdbserver implemented it.
1939 *** Changes in GDB 6.5
1943 Renesas M32C/M16C m32c-elf
1945 Morpho Technologies ms1 ms1-elf
1949 init-if-undefined Initialize a convenience variable, but
1950 only if it doesn't already have a value.
1952 The following commands are presently only implemented for native GNU/Linux:
1954 checkpoint Save a snapshot of the program state.
1956 restart <n> Return the program state to a
1957 previously saved state.
1959 info checkpoints List currently saved checkpoints.
1961 delete-checkpoint <n> Delete a previously saved checkpoint.
1963 set|show detach-on-fork Tell gdb whether to detach from a newly
1964 forked process, or to keep debugging it.
1966 info forks List forks of the user program that
1967 are available to be debugged.
1969 fork <n> Switch to debugging one of several
1970 forks of the user program that are
1971 available to be debugged.
1973 delete-fork <n> Delete a fork from the list of forks
1974 that are available to be debugged (and
1975 kill the forked process).
1977 detach-fork <n> Delete a fork from the list of forks
1978 that are available to be debugged (and
1979 allow the process to continue).
1983 Morpho Technologies ms2 ms1-elf
1985 * Improved Windows host support
1987 GDB now builds as a cross debugger hosted on i686-mingw32, including
1988 native console support, and remote communications using either
1989 network sockets or serial ports.
1991 * Improved Modula-2 language support
1993 GDB can now print most types in the Modula-2 syntax. This includes:
1994 basic types, set types, record types, enumerated types, range types,
1995 pointer types and ARRAY types. Procedure var parameters are correctly
1996 printed and hexadecimal addresses and character constants are also
1997 written in the Modula-2 syntax. Best results can be obtained by using
1998 GNU Modula-2 together with the -gdwarf-2 command line option.
2002 The ARM rdi-share module.
2004 The Netware NLM debug server.
2006 *** Changes in GDB 6.4
2008 * New native configurations
2010 OpenBSD/arm arm*-*-openbsd*
2011 OpenBSD/mips64 mips64-*-openbsd*
2015 Morpho Technologies ms1 ms1-elf
2017 * New command line options
2019 --batch-silent As for --batch, but totally silent.
2020 --return-child-result The debugger will exist with the same value
2021 the child (debugged) program exited with.
2022 --eval-command COMMAND, -ex COMMAND
2023 Execute a single GDB CLI command. This may be
2024 specified multiple times and in conjunction
2025 with the --command (-x) option.
2027 * Deprecated commands removed
2029 The following commands, that were deprecated in 2000, have been
2033 set|show arm disassembly-flavor set|show arm disassembler
2034 othernames set arm disassembler
2035 set|show remotedebug set|show debug remote
2036 set|show archdebug set|show debug arch
2037 set|show eventdebug set|show debug event
2040 * New BSD user-level threads support
2042 It is now possible to debug programs using the user-level threads
2043 library on OpenBSD and FreeBSD. Currently supported (target)
2046 FreeBSD/amd64 x86_64-*-freebsd*
2047 FreeBSD/i386 i386-*-freebsd*
2048 OpenBSD/i386 i386-*-openbsd*
2050 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2051 are not yet supported.
2053 * New support for Matsushita MN10300 w/sim added
2054 (Work in progress). mn10300-elf.
2056 * REMOVED configurations and files
2058 VxWorks and the XDR protocol *-*-vxworks
2059 Motorola MCORE mcore-*-*
2060 National Semiconductor NS32000 ns32k-*-*
2062 * New "set print array-indexes" command
2064 After turning this setting "on", GDB prints the index of each element
2065 when displaying arrays. The default is "off" to preserve the previous
2068 * VAX floating point support
2070 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2072 * User-defined command support
2074 In addition to using $arg0..$arg9 for argument passing, it is now possible
2075 to use $argc to determine now many arguments have been passed. See the
2076 section on user-defined commands in the user manual for more information.
2078 *** Changes in GDB 6.3:
2080 * New command line option
2082 GDB now accepts -l followed by a number to set the timeout for remote
2085 * GDB works with GCC -feliminate-dwarf2-dups
2087 GDB now supports a more compact representation of DWARF-2 debug
2088 information using DW_FORM_ref_addr references. These are produced
2089 by GCC with the option -feliminate-dwarf2-dups and also by some
2090 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2091 to use -feliminate-dwarf2-dups.
2093 * Internationalization
2095 When supported by the host system, GDB will be built with
2096 internationalization (libintl). The task of marking up the sources is
2097 continued, we're looking forward to our first translation.
2101 Initial support for debugging programs compiled with the GNAT
2102 implementation of the Ada programming language has been integrated
2103 into GDB. In this release, support is limited to expression evaluation.
2105 * New native configurations
2107 GNU/Linux/m32r m32r-*-linux-gnu
2111 GDB's remote protocol now includes support for the 'p' packet. This
2112 packet is used to fetch individual registers from a remote inferior.
2114 * END-OF-LIFE registers[] compatibility module
2116 GDB's internal register infrastructure has been completely rewritten.
2117 The new infrastructure making possible the implementation of key new
2118 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2121 GDB 6.3 will be the last release to include the the registers[]
2122 compatibility module that allowed out-of-date configurations to
2123 continue to work. This change directly impacts the following
2133 powerpc bdm protocol
2135 Unless there is activity to revive these configurations, they will be
2136 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2138 * OBSOLETE configurations and files
2140 Configurations that have been declared obsolete in this release have
2141 been commented out. Unless there is activity to revive these
2142 configurations, the next release of GDB will have their sources
2143 permanently REMOVED.
2152 *** Changes in GDB 6.2.1:
2154 * MIPS `break main; run' gave an heuristic-fence-post warning
2156 When attempting to run even a simple program, a warning about
2157 heuristic-fence-post being hit would be reported. This problem has
2160 * MIPS IRIX 'long double' crashed GDB
2162 When examining a long double variable, GDB would get a segmentation
2163 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2164 IRIX long double values).
2168 A bug in the VAX stack code was causing problems with the "next"
2169 command. This problem has been fixed.
2171 *** Changes in GDB 6.2:
2173 * Fix for ``many threads''
2175 On GNU/Linux systems that use the NPTL threads library, a program
2176 rapidly creating and deleting threads would confuse GDB leading to the
2179 ptrace: No such process.
2180 thread_db_get_info: cannot get thread info: generic error
2182 This problem has been fixed.
2184 * "-async" and "-noasync" options removed.
2186 Support for the broken "-noasync" option has been removed (it caused
2189 * New ``start'' command.
2191 This command runs the program until the begining of the main procedure.
2193 * New BSD Kernel Data Access Library (libkvm) interface
2195 Using ``target kvm'' it is now possible to debug kernel core dumps and
2196 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2197 platforms. Currently supported (native-only) configurations are:
2199 FreeBSD/amd64 x86_64-*-freebsd*
2200 FreeBSD/i386 i?86-*-freebsd*
2201 NetBSD/i386 i?86-*-netbsd*
2202 NetBSD/m68k m68*-*-netbsd*
2203 NetBSD/sparc sparc-*-netbsd*
2204 OpenBSD/amd64 x86_64-*-openbsd*
2205 OpenBSD/i386 i?86-*-openbsd*
2206 OpenBSD/m68k m68*-openbsd*
2207 OpenBSD/sparc sparc-*-openbsd*
2209 * Signal trampoline code overhauled
2211 Many generic problems with GDB's signal handling code have been fixed.
2212 These include: backtraces through non-contiguous stacks; recognition
2213 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2214 call; backtrace through a signal trampoline; step into and out of
2215 signal handlers; and single-stepping in the signal trampoline.
2217 Please note that kernel bugs are a limiting factor here. These
2218 features have been shown to work on an s390 GNU/Linux system that
2219 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2221 * Cygwin support for DWARF 2 added.
2223 * New native configurations
2225 GNU/Linux/hppa hppa*-*-linux*
2226 OpenBSD/hppa hppa*-*-openbsd*
2227 OpenBSD/m68k m68*-*-openbsd*
2228 OpenBSD/m88k m88*-*-openbsd*
2229 OpenBSD/powerpc powerpc-*-openbsd*
2230 NetBSD/vax vax-*-netbsd*
2231 OpenBSD/vax vax-*-openbsd*
2233 * END-OF-LIFE frame compatibility module
2235 GDB's internal frame infrastructure has been completely rewritten.
2236 The new infrastructure making it possible to support key new features
2237 including DWARF 2 Call Frame Information. To aid in the task of
2238 migrating old configurations to this new infrastructure, a
2239 compatibility module, that allowed old configurations to continue to
2240 work, was also included.
2242 GDB 6.2 will be the last release to include this frame compatibility
2243 module. This change directly impacts the following configurations:
2253 Unless there is activity to revive these configurations, they will be
2254 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2256 * REMOVED configurations and files
2258 Sun 3, running SunOS 3 m68*-*-sunos3*
2259 Sun 3, running SunOS 4 m68*-*-sunos4*
2260 Sun 2, running SunOS 3 m68000-*-sunos3*
2261 Sun 2, running SunOS 4 m68000-*-sunos4*
2262 Motorola 680x0 running LynxOS m68*-*-lynxos*
2263 AT&T 3b1/Unix pc m68*-att-*
2264 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2265 decstation mips-dec-* mips-little-*
2266 riscos mips-*-riscos* mips-*-sysv*
2267 sonymips mips-sony-*
2268 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2270 *** Changes in GDB 6.1.1:
2272 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2274 The TUI (Text-mode User Interface) is now built as part of a default
2275 GDB configuration. It is enabled by either selecting the TUI with the
2276 command line option "-i=tui" or by running the separate "gdbtui"
2277 program. For more information on the TUI, see the manual "Debugging
2280 * Pending breakpoint support (also included in GDB 6.1)
2282 Support has been added to allow you to specify breakpoints in shared
2283 libraries that have not yet been loaded. If a breakpoint location
2284 cannot be found, and the "breakpoint pending" option is set to auto,
2285 GDB queries you if you wish to make the breakpoint pending on a future
2286 shared-library load. If and when GDB resolves the breakpoint symbol,
2287 the pending breakpoint is removed as one or more regular breakpoints
2290 Pending breakpoints are very useful for GCJ Java debugging.
2292 * Fixed ISO-C build problems
2294 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2295 non ISO-C code that stopped them being built using a more strict ISO-C
2296 compiler (e.g., IBM's C compiler).
2298 * Fixed build problem on IRIX 5
2300 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2301 wasn't able to compile compile on an IRIX 5 system.
2303 * Added execute permission to gdb/gdbserver/configure
2305 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2306 permission. This bug would cause configure to fail on a number of
2307 systems (Solaris, IRIX). Ref: server/519.
2309 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2311 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2312 has been updated to use constant array sizes.
2314 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2316 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2317 its generated DWARF Call Frame Info. This encoding was causing GDB to
2318 panic, that panic has been fixed. Ref: gdb/1628.
2320 * Fixed a problem when examining parameters in shared library code.
2322 When examining parameters in optimized shared library code generated
2323 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2324 not available''. GDB now correctly displays the variable's value.
2326 *** Changes in GDB 6.1:
2328 * Removed --with-mmalloc
2330 Support for the mmalloc memory manager has been removed, as it
2331 conflicted with the internal gdb byte cache.
2333 * Changes in AMD64 configurations
2335 The AMD64 target now includes the %cs and %ss registers. As a result
2336 the AMD64 remote protocol has changed; this affects the floating-point
2337 and SSE registers. If you rely on those registers for your debugging,
2338 you should upgrade gdbserver on the remote side.
2340 * Revised SPARC target
2342 The SPARC target has been completely revised, incorporating the
2343 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2344 support for LynxOS and SunOS 4 has been dropped. Calling functions
2345 from within GDB on operating systems with a non-executable stack
2346 (Solaris, OpenBSD) now works.
2350 GDB has a new C++ demangler which does a better job on the mangled
2351 names generated by current versions of g++. It also runs faster, so
2352 with this and other changes gdb should now start faster on large C++
2355 * DWARF 2 Location Expressions
2357 GDB support for location expressions has been extended to support function
2358 arguments and frame bases. Older versions of GDB could crash when they
2361 * C++ nested types and namespaces
2363 GDB's support for nested types and namespaces in C++ has been
2364 improved, especially if you use the DWARF 2 debugging format. (This
2365 is the default for recent versions of GCC on most platforms.)
2366 Specifically, if you have a class "Inner" defined within a class or
2367 namespace "Outer", then GDB realizes that the class's name is
2368 "Outer::Inner", not simply "Inner". This should greatly reduce the
2369 frequency of complaints about not finding RTTI symbols. In addition,
2370 if you are stopped at inside of a function defined within a namespace,
2371 GDB modifies its name lookup accordingly.
2373 * New native configurations
2375 NetBSD/amd64 x86_64-*-netbsd*
2376 OpenBSD/amd64 x86_64-*-openbsd*
2377 OpenBSD/alpha alpha*-*-openbsd*
2378 OpenBSD/sparc sparc-*-openbsd*
2379 OpenBSD/sparc64 sparc64-*-openbsd*
2381 * New debugging protocols
2383 M32R with SDI protocol m32r-*-elf*
2385 * "set prompt-escape-char" command deleted.
2387 The command "set prompt-escape-char" has been deleted. This command,
2388 and its very obscure effet on GDB's prompt, was never documented,
2389 tested, nor mentioned in the NEWS file.
2391 * OBSOLETE configurations and files
2393 Configurations that have been declared obsolete in this release have
2394 been commented out. Unless there is activity to revive these
2395 configurations, the next release of GDB will have their sources
2396 permanently REMOVED.
2398 Sun 3, running SunOS 3 m68*-*-sunos3*
2399 Sun 3, running SunOS 4 m68*-*-sunos4*
2400 Sun 2, running SunOS 3 m68000-*-sunos3*
2401 Sun 2, running SunOS 4 m68000-*-sunos4*
2402 Motorola 680x0 running LynxOS m68*-*-lynxos*
2403 AT&T 3b1/Unix pc m68*-att-*
2404 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2405 decstation mips-dec-* mips-little-*
2406 riscos mips-*-riscos* mips-*-sysv*
2407 sonymips mips-sony-*
2408 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2410 * REMOVED configurations and files
2412 SGI Irix-4.x mips-sgi-irix4 or iris4
2413 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2414 Z8000 simulator z8k-zilog-none or z8ksim
2415 Matsushita MN10200 w/simulator mn10200-*-*
2416 H8/500 simulator h8500-hitachi-hms or h8500hms
2417 HP/PA running BSD hppa*-*-bsd*
2418 HP/PA running OSF/1 hppa*-*-osf*
2419 HP/PA Pro target hppa*-*-pro*
2420 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2421 386BSD i[3456]86-*-bsd*
2422 Sequent family i[3456]86-sequent-sysv4*
2423 i[3456]86-sequent-sysv*
2424 i[3456]86-sequent-bsd*
2425 SPARC running LynxOS sparc-*-lynxos*
2426 SPARC running SunOS 4 sparc-*-sunos4*
2427 Tsqware Sparclet sparclet-*-*
2428 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2430 *** Changes in GDB 6.0:
2434 Support for debugging the Objective-C programming language has been
2435 integrated into GDB.
2437 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2439 DWARF 2's Call Frame Information makes available compiler generated
2440 information that more exactly describes the program's run-time stack.
2441 By using this information, GDB is able to provide more robust stack
2444 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2445 have been updated to use a new backtrace mechanism which includes
2446 DWARF 2 CFI support.
2450 GDB's remote protocol has been extended to include support for hosted
2451 file I/O (where the remote target uses GDB's file system). See GDB's
2452 remote protocol documentation for details.
2454 * All targets using the new architecture framework.
2456 All of GDB's targets have been updated to use the new internal
2457 architecture framework. The way is now open for future GDB releases
2458 to include cross-architecture native debugging support (i386 on amd64,
2461 * GNU/Linux's Thread Local Storage (TLS)
2463 GDB now includes support for for the GNU/Linux implementation of
2464 per-thread variables.
2466 * GNU/Linux's Native POSIX Thread Library (NPTL)
2468 GDB's thread code has been updated to work with either the new
2469 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2471 * Separate debug info.
2473 GDB, in conjunction with BINUTILS, now supports a mechanism for
2474 automatically loading debug information from a separate file. Instead
2475 of shipping full debug and non-debug versions of system libraries,
2476 system integrators can now instead ship just the stripped libraries
2477 and optional debug files.
2479 * DWARF 2 Location Expressions
2481 DWARF 2 Location Expressions allow the compiler to more completely
2482 describe the location of variables (even in optimized code) to the
2485 GDB now includes preliminary support for location expressions (support
2486 for DW_OP_piece is still missing).
2490 A number of long standing bugs that caused GDB to die while starting a
2491 Java application have been fixed. GDB's Java support is now
2492 considered "useable".
2494 * GNU/Linux support for fork, vfork, and exec.
2496 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2497 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2500 * GDB supports logging output to a file
2502 There are two new commands, "set logging" and "show logging", which can be
2503 used to capture GDB's output to a file.
2505 * The meaning of "detach" has changed for gdbserver
2507 The "detach" command will now resume the application, as documented. To
2508 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2511 * d10v, m68hc11 `regs' command deprecated
2513 The `info registers' command has been updated so that it displays the
2514 registers using a format identical to the old `regs' command.
2518 A new command, "maint set profile on/off", has been added. This command can
2519 be used to enable or disable profiling while running GDB, to profile a
2520 session or a set of commands. In addition there is a new configure switch,
2521 "--enable-profiling", which will cause GDB to be compiled with profiling
2522 data, for more informative profiling results.
2524 * Default MI syntax changed to "mi2".
2526 The default MI (machine interface) syntax, enabled by the command line
2527 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2528 "mi1", can be enabled by specifying the option "-i=mi1".
2530 Support for the original "mi0" syntax (included in GDB 5.0) has been
2533 Fix for gdb/192: removed extraneous space when displaying frame level.
2534 Fix for gdb/672: update changelist is now output in mi list format.
2535 Fix for gdb/702: a -var-assign that updates the value now shows up
2536 in a subsequent -var-update.
2538 * New native configurations.
2540 FreeBSD/amd64 x86_64-*-freebsd*
2542 * Multi-arched targets.
2544 HP/PA HPUX11 hppa*-*-hpux*
2545 Renesas M32R/D w/simulator m32r-*-elf*
2547 * OBSOLETE configurations and files
2549 Configurations that have been declared obsolete in this release have
2550 been commented out. Unless there is activity to revive these
2551 configurations, the next release of GDB will have their sources
2552 permanently REMOVED.
2554 Z8000 simulator z8k-zilog-none or z8ksim
2555 Matsushita MN10200 w/simulator mn10200-*-*
2556 H8/500 simulator h8500-hitachi-hms or h8500hms
2557 HP/PA running BSD hppa*-*-bsd*
2558 HP/PA running OSF/1 hppa*-*-osf*
2559 HP/PA Pro target hppa*-*-pro*
2560 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2561 Sequent family i[3456]86-sequent-sysv4*
2562 i[3456]86-sequent-sysv*
2563 i[3456]86-sequent-bsd*
2564 Tsqware Sparclet sparclet-*-*
2565 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2567 * REMOVED configurations and files
2570 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2571 IBM AIX PS/2 i[3456]86-*-aix
2572 i386 running Mach 3.0 i[3456]86-*-mach3*
2573 i386 running Mach i[3456]86-*-mach*
2574 i386 running OSF/1 i[3456]86-*osf1mk*
2575 HP/Apollo 68k Family m68*-apollo*-sysv*,
2577 m68*-hp-bsd*, m68*-hp-hpux*
2578 Argonaut Risc Chip (ARC) arc-*-*
2579 Mitsubishi D30V d30v-*-*
2580 Fujitsu FR30 fr30-*-elf*
2581 OS/9000 i[34]86-*-os9k
2582 I960 with MON960 i960-*-coff
2584 * MIPS $fp behavior changed
2586 The convenience variable $fp, for the MIPS, now consistently returns
2587 the address of the current frame's base. Previously, depending on the
2588 context, $fp could refer to either $sp or the current frame's base
2589 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2590 The GNU Source-Level Debugger''.
2592 *** Changes in GDB 5.3:
2594 * GNU/Linux shared library multi-threaded performance improved.
2596 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2597 `/proc', in preference to `ptrace' for memory reads. This may result
2598 in an improvement in the start-up time of multi-threaded, shared
2599 library applications when run under GDB. One GDB user writes: ``loads
2600 shared libs like mad''.
2602 * ``gdbserver'' now supports multi-threaded applications on some targets
2604 Support for debugging multi-threaded applications which use
2605 the GNU/Linux LinuxThreads package has been added for
2606 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2607 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2609 * GDB now supports C/C++ preprocessor macros.
2611 GDB now expands preprocessor macro invocations in C/C++ expressions,
2612 and provides various commands for showing macro definitions and how
2615 The new command `macro expand EXPRESSION' expands any macro
2616 invocations in expression, and shows the result.
2618 The new command `show macro MACRO-NAME' shows the definition of the
2619 macro named MACRO-NAME, and where it was defined.
2621 Most compilers don't include information about macros in the debugging
2622 information by default. In GCC 3.1, for example, you need to compile
2623 your program with the options `-gdwarf-2 -g3'. If the macro
2624 information is present in the executable, GDB will read it.
2626 * Multi-arched targets.
2628 DEC Alpha (partial) alpha*-*-*
2629 DEC VAX (partial) vax-*-*
2631 National Semiconductor NS32000 (partial) ns32k-*-*
2632 Motorola 68000 (partial) m68k-*-*
2633 Motorola MCORE mcore-*-*
2637 Fujitsu FRV architecture added by Red Hat frv*-*-*
2640 * New native configurations
2642 Alpha NetBSD alpha*-*-netbsd*
2643 SH NetBSD sh*-*-netbsdelf*
2644 MIPS NetBSD mips*-*-netbsd*
2645 UltraSPARC NetBSD sparc64-*-netbsd*
2647 * OBSOLETE configurations and files
2649 Configurations that have been declared obsolete in this release have
2650 been commented out. Unless there is activity to revive these
2651 configurations, the next release of GDB will have their sources
2652 permanently REMOVED.
2654 Mitsubishi D30V d30v-*-*
2655 OS/9000 i[34]86-*-os9k
2656 IBM AIX PS/2 i[3456]86-*-aix
2657 Fujitsu FR30 fr30-*-elf*
2658 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2659 Argonaut Risc Chip (ARC) arc-*-*
2660 i386 running Mach 3.0 i[3456]86-*-mach3*
2661 i386 running Mach i[3456]86-*-mach*
2662 i386 running OSF/1 i[3456]86-*osf1mk*
2663 HP/Apollo 68k Family m68*-apollo*-sysv*,
2665 m68*-hp-bsd*, m68*-hp-hpux*
2666 I960 with MON960 i960-*-coff
2668 * OBSOLETE languages
2670 CHILL, a Pascal like language used by telecommunications companies.
2672 * REMOVED configurations and files
2674 AMD 29k family via UDI a29k-amd-udi, udi29k
2675 A29K VxWorks a29k-*-vxworks
2676 AMD 29000 embedded, using EBMON a29k-none-none
2677 AMD 29000 embedded with COFF a29k-none-coff
2678 AMD 29000 embedded with a.out a29k-none-aout
2680 testsuite/gdb.hp/gdb.threads-hp/ directory
2682 * New command "set max-user-call-depth <nnn>"
2684 This command allows the user to limit the call depth of user-defined
2685 commands. The default is 1024.
2687 * Changes in FreeBSD/i386 native debugging.
2689 Support for the "generate-core-file" has been added.
2691 * New commands "dump", "append", and "restore".
2693 These commands allow data to be copied from target memory
2694 to a bfd-format or binary file (dump and append), and back
2695 from a file into memory (restore).
2697 * Improved "next/step" support on multi-processor Alpha Tru64.
2699 The previous single-step mechanism could cause unpredictable problems,
2700 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2701 of a software single-step mechanism prevents this.
2703 *** Changes in GDB 5.2.1:
2711 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2712 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2713 Fix, by Joel Brobecker imported from mainline.
2715 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2716 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2717 Fix, by Fred Fish, imported from mainline.
2719 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2720 Surprisingly enough, it works now.
2721 By Michal Ludvig, imported from mainline.
2723 i386 hardware watchpoint support:
2724 avoid misses on second run for some targets.
2725 By Pierre Muller, imported from mainline.
2727 *** Changes in GDB 5.2:
2729 * New command "set trust-readonly-sections on[off]".
2731 This command is a hint that tells gdb that read-only sections
2732 really are read-only (ie. that their contents will not change).
2733 In this mode, gdb will go to the object file rather than the
2734 target to read memory from read-only sections (such as ".text").
2735 This can be a significant performance improvement on some
2736 (notably embedded) targets.
2738 * New command "generate-core-file" (or "gcore").
2740 This new gdb command allows the user to drop a core file of the child
2741 process state at any time. So far it's been implemented only for
2742 GNU/Linux and Solaris, but should be relatively easily ported to other
2743 hosts. Argument is core file name (defaults to core.<pid>).
2745 * New command line option
2747 GDB now accepts --pid or -p followed by a process id.
2749 * Change in command line behavior -- corefiles vs. process ids.
2751 There is a subtle behavior in the way in which GDB handles
2752 command line arguments. The first non-flag argument is always
2753 a program to debug, but the second non-flag argument may either
2754 be a corefile or a process id. Previously, GDB would attempt to
2755 open the second argument as a corefile, and if that failed, would
2756 issue a superfluous error message and then attempt to attach it as
2757 a process. Now, if the second argument begins with a non-digit,
2758 it will be treated as a corefile. If it begins with a digit,
2759 GDB will attempt to attach it as a process, and if no such process
2760 is found, will then attempt to open it as a corefile.
2762 * Changes in ARM configurations.
2764 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2765 configuration is fully multi-arch.
2767 * New native configurations
2769 ARM NetBSD arm*-*-netbsd*
2770 x86 OpenBSD i[3456]86-*-openbsd*
2771 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2772 Sparc64 running FreeBSD sparc64-*-freebsd*
2776 Sanyo XStormy16 xstormy16-elf
2778 * OBSOLETE configurations and files
2780 Configurations that have been declared obsolete in this release have
2781 been commented out. Unless there is activity to revive these
2782 configurations, the next release of GDB will have their sources
2783 permanently REMOVED.
2785 AMD 29k family via UDI a29k-amd-udi, udi29k
2786 A29K VxWorks a29k-*-vxworks
2787 AMD 29000 embedded, using EBMON a29k-none-none
2788 AMD 29000 embedded with COFF a29k-none-coff
2789 AMD 29000 embedded with a.out a29k-none-aout
2791 testsuite/gdb.hp/gdb.threads-hp/ directory
2793 * REMOVED configurations and files
2795 TI TMS320C80 tic80-*-*
2797 PowerPC Solaris powerpcle-*-solaris*
2798 PowerPC Windows NT powerpcle-*-cygwin32
2799 PowerPC Netware powerpc-*-netware*
2800 Harris/CXUX m88k m88*-harris-cxux*
2801 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2802 ns32k-utek-sysv* ns32k-utek-*
2803 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2804 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2805 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2806 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2807 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2809 * Changes to command line processing
2811 The new `--args' feature can be used to specify command-line arguments
2812 for the inferior from gdb's command line.
2814 * Changes to key bindings
2816 There is a new `operate-and-get-next' function bound to `C-o'.
2818 *** Changes in GDB 5.1.1
2820 Fix compile problem on DJGPP.
2822 Fix a problem with floating-point registers on the i386 being
2825 Fix to stop GDB crashing on .debug_str debug info.
2827 Numerous documentation fixes.
2829 Numerous testsuite fixes.
2831 *** Changes in GDB 5.1:
2833 * New native configurations
2835 Alpha FreeBSD alpha*-*-freebsd*
2836 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2837 MIPS GNU/Linux mips*-*-linux*
2838 MIPS SGI Irix 6.x mips*-sgi-irix6*
2839 ia64 AIX ia64-*-aix*
2840 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2844 Motorola 68HC11 and 68HC12 m68hc11-elf
2846 UltraSparc running GNU/Linux sparc64-*-linux*
2848 * OBSOLETE configurations and files
2850 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2851 Harris/CXUX m88k m88*-harris-cxux*
2852 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2853 ns32k-utek-sysv* ns32k-utek-*
2854 TI TMS320C80 tic80-*-*
2856 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2857 PowerPC Solaris powerpcle-*-solaris*
2858 PowerPC Windows NT powerpcle-*-cygwin32
2859 PowerPC Netware powerpc-*-netware*
2860 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2861 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2862 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2863 Apple Macintosh (MPW) host N/A
2865 stuff.c (Program to stuff files into a specially prepared space in kdb)
2866 kdb-start.c (Main loop for the standalone kernel debugger)
2868 Configurations that have been declared obsolete in this release have
2869 been commented out. Unless there is activity to revive these
2870 configurations, the next release of GDB will have their sources
2871 permanently REMOVED.
2873 * REMOVED configurations and files
2875 Altos 3068 m68*-altos-*
2876 Convex c1-*-*, c2-*-*
2878 ARM RISCix arm-*-* (as host)
2882 * GDB has been converted to ISO C.
2884 GDB's source code has been converted to ISO C. In particular, the
2885 sources are fully protoized, and rely on standard headers being
2890 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2892 * The MI enabled by default.
2894 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2895 revised and enabled by default. Packages which use GDB as a debugging
2896 engine behind a UI or another front end are encouraged to switch to
2897 using the GDB/MI interface, instead of the old annotations interface
2898 which is now deprecated.
2900 * Support for debugging Pascal programs.
2902 GDB now includes support for debugging Pascal programs. The following
2903 main features are supported:
2905 - Pascal-specific data types such as sets;
2907 - automatic recognition of Pascal sources based on file-name
2910 - Pascal-style display of data types, variables, and functions;
2912 - a Pascal expression parser.
2914 However, some important features are not yet supported.
2916 - Pascal string operations are not supported at all;
2918 - there are some problems with boolean types;
2920 - Pascal type hexadecimal constants are not supported
2921 because they conflict with the internal variables format;
2923 - support for Pascal objects and classes is not full yet;
2925 - unlike Pascal, GDB is case-sensitive for symbol names.
2927 * Changes in completion.
2929 Commands such as `shell', `run' and `set args', which pass arguments
2930 to inferior programs, now complete on file names, similar to what
2931 users expect at the shell prompt.
2933 Commands which accept locations, such as `disassemble', `print',
2934 `breakpoint', `until', etc. now complete on filenames as well as
2935 program symbols. Thus, if you type "break foob TAB", and the source
2936 files linked into the programs include `foobar.c', that file name will
2937 be one of the candidates for completion. However, file names are not
2938 considered for completion after you typed a colon that delimits a file
2939 name from a name of a function in that file, as in "break foo.c:bar".
2941 `set demangle-style' completes on available demangling styles.
2943 * New platform-independent commands:
2945 It is now possible to define a post-hook for a command as well as a
2946 hook that runs before the command. For more details, see the
2947 documentation of `hookpost' in the GDB manual.
2949 * Changes in GNU/Linux native debugging.
2951 Support for debugging multi-threaded programs has been completely
2952 revised for all platforms except m68k and sparc. You can now debug as
2953 many threads as your system allows you to have.
2955 Attach/detach is supported for multi-threaded programs.
2957 Support for SSE registers was added for x86. This doesn't work for
2958 multi-threaded programs though.
2960 * Changes in MIPS configurations.
2962 Multi-arch support is enabled for all MIPS configurations.
2964 GDB can now be built as native debugger on SGI Irix 6.x systems for
2965 debugging n32 executables. (Debugging 64-bit executables is not yet
2968 * Unified support for hardware watchpoints in all x86 configurations.
2970 Most (if not all) native x86 configurations support hardware-assisted
2971 breakpoints and watchpoints in a unified manner. This support
2972 implements debug register sharing between watchpoints, which allows to
2973 put a virtually infinite number of watchpoints on the same address,
2974 and also supports watching regions up to 16 bytes with several debug
2977 The new maintenance command `maintenance show-debug-regs' toggles
2978 debugging print-outs in functions that insert, remove, and test
2979 watchpoints and hardware breakpoints.
2981 * Changes in the DJGPP native configuration.
2983 New command ``info dos sysinfo'' displays assorted information about
2984 the CPU, OS, memory, and DPMI server.
2986 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2987 display information about segment descriptors stored in GDT, LDT, and
2990 New commands ``info dos pde'' and ``info dos pte'' display entries
2991 from Page Directory and Page Tables (for now works with CWSDPMI only).
2992 New command ``info dos address-pte'' displays the Page Table entry for
2993 a given linear address.
2995 GDB can now pass command lines longer than 126 characters to the
2996 program being debugged (requires an update to the libdbg.a library
2997 which is part of the DJGPP development kit).
2999 DWARF2 debug info is now supported.
3001 It is now possible to `step' and `next' through calls to `longjmp'.
3003 * Changes in documentation.
3005 All GDB documentation was converted to GFDL, the GNU Free
3006 Documentation License.
3008 Tracepoints-related commands are now fully documented in the GDB
3011 TUI, the Text-mode User Interface, is now documented in the manual.
3013 Tracepoints-related commands are now fully documented in the GDB
3016 The "GDB Internals" manual now has an index. It also includes
3017 documentation of `ui_out' functions, GDB coding standards, x86
3018 hardware watchpoints, and memory region attributes.
3020 * GDB's version number moved to ``version.in''
3022 The Makefile variable VERSION has been replaced by the file
3023 ``version.in''. People creating GDB distributions should update the
3024 contents of this file.
3028 GUD support is now a standard part of the EMACS distribution.
3030 *** Changes in GDB 5.0:
3032 * Improved support for debugging FP programs on x86 targets
3034 Unified and much-improved support for debugging floating-point
3035 programs on all x86 targets. In particular, ``info float'' now
3036 displays the FP registers in the same format on all x86 targets, with
3037 greater level of detail.
3039 * Improvements and bugfixes in hardware-assisted watchpoints
3041 It is now possible to watch array elements, struct members, and
3042 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3043 on x86 targets no longer erroneously trigger when the address is
3046 * Improvements in the native DJGPP version of GDB
3048 The distribution now includes all the scripts and auxiliary files
3049 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3050 machines ``out of the box''.
3052 The DJGPP version can now debug programs that use signals. It is
3053 possible to catch signals that happened in the debuggee, deliver
3054 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3055 would kill the program being debugged.) Programs that hook hardware
3056 interrupts (keyboard, timer, etc.) can also be debugged.
3058 It is now possible to debug DJGPP programs that redirect their
3059 standard handles or switch them to raw (as opposed to cooked) mode, or
3060 even close them. The command ``run < foo > bar'' works as expected,
3061 and ``info terminal'' reports useful information about the debuggee's
3062 terminal, including raw/cooked mode, redirection, etc.
3064 The DJGPP version now uses termios functions for console I/O, which
3065 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3068 DOS-style file names with drive letters are now fully supported by
3071 It is now possible to debug DJGPP programs that switch their working
3072 directory. It is also possible to rerun the debuggee any number of
3073 times without restarting GDB; thus, you can use the same setup,
3074 breakpoints, etc. for many debugging sessions.
3076 * New native configurations
3078 ARM GNU/Linux arm*-*-linux*
3079 PowerPC GNU/Linux powerpc-*-linux*
3083 Motorola MCore mcore-*-*
3084 x86 VxWorks i[3456]86-*-vxworks*
3085 PowerPC VxWorks powerpc-*-vxworks*
3086 TI TMS320C80 tic80-*-*
3088 * OBSOLETE configurations
3090 Altos 3068 m68*-altos-*
3091 Convex c1-*-*, c2-*-*
3093 ARM RISCix arm-*-* (as host)
3096 Configurations that have been declared obsolete will be commented out,
3097 but the code will be left in place. If there is no activity to revive
3098 these configurations before the next release of GDB, the sources will
3099 be permanently REMOVED.
3101 * Gould support removed
3103 Support for the Gould PowerNode and NP1 has been removed.
3105 * New features for SVR4
3107 On SVR4 native platforms (such as Solaris), if you attach to a process
3108 without first loading a symbol file, GDB will now attempt to locate and
3109 load symbols from the running process's executable file.
3111 * Many C++ enhancements
3113 C++ support has been greatly improved. Overload resolution now works properly
3114 in almost all cases. RTTI support is on the way.
3116 * Remote targets can connect to a sub-program
3118 A popen(3) style serial-device has been added. This device starts a
3119 sub-process (such as a stand-alone simulator) and then communicates
3120 with that. The sub-program to run is specified using the syntax
3121 ``|<program> <args>'' vis:
3123 (gdb) set remotedebug 1
3124 (gdb) target extended-remote |mn10300-elf-sim program-args
3126 * MIPS 64 remote protocol
3128 A long standing bug in the mips64 remote protocol where by GDB
3129 expected certain 32 bit registers (ex SR) to be transfered as 32
3130 instead of 64 bits has been fixed.
3132 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3133 added to provide backward compatibility with older versions of GDB.
3135 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3137 The command ``set remotebinarydownload'' command has been replaced by
3138 ``set remote X-packet''. Other commands in ``set remote'' family
3139 include ``set remote P-packet''.
3141 * Breakpoint commands accept ranges.
3143 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3144 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3145 ``tracepoint passcount'' also accepts a range of tracepoints.
3147 * ``apropos'' command added.
3149 The ``apropos'' command searches through command names and
3150 documentation strings, printing out matches, making it much easier to
3151 try to find a command that does what you are looking for.
3155 A new machine oriented interface (MI) has been added to GDB. This
3156 interface is designed for debug environments running GDB as a separate
3157 process. This is part of the long term libGDB project. See the
3158 "GDB/MI" chapter of the GDB manual for further information. It can be
3159 enabled by configuring with:
3161 .../configure --enable-gdbmi
3163 *** Changes in GDB-4.18:
3165 * New native configurations
3167 HP-UX 10.20 hppa*-*-hpux10.20
3168 HP-UX 11.x hppa*-*-hpux11.0*
3169 M68K GNU/Linux m68*-*-linux*
3173 Fujitsu FR30 fr30-*-elf*
3174 Intel StrongARM strongarm-*-*
3175 Mitsubishi D30V d30v-*-*
3177 * OBSOLETE configurations
3179 Gould PowerNode, NP1 np1-*-*, pn-*-*
3181 Configurations that have been declared obsolete will be commented out,
3182 but the code will be left in place. If there is no activity to revive
3183 these configurations before the next release of GDB, the sources will
3184 be permanently REMOVED.
3188 As a compatibility experiment, GDB's source files buildsym.h and
3189 buildsym.c have been converted to pure standard C, no longer
3190 containing any K&R compatibility code. We believe that all systems in
3191 use today either come with a standard C compiler, or have a GCC port
3192 available. If this is not true, please report the affected
3193 configuration to bug-gdb@gnu.org immediately. See the README file for
3194 information about getting a standard C compiler if you don't have one
3199 GDB now uses readline 2.2.
3201 * set extension-language
3203 You can now control the mapping between filename extensions and source
3204 languages by using the `set extension-language' command. For instance,
3205 you can ask GDB to treat .c files as C++ by saying
3206 set extension-language .c c++
3207 The command `info extensions' lists all of the recognized extensions
3208 and their associated languages.
3210 * Setting processor type for PowerPC and RS/6000
3212 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3213 you can use the `set processor' command to specify what variant of the
3214 PowerPC family you are debugging. The command
3218 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3219 following PowerPC and RS6000 variants:
3221 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3222 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3224 403GC IBM PowerPC 403GC
3225 505 Motorola PowerPC 505
3226 860 Motorola PowerPC 860 or 850
3227 601 Motorola PowerPC 601
3228 602 Motorola PowerPC 602
3229 603 Motorola/IBM PowerPC 603 or 603e
3230 604 Motorola PowerPC 604 or 604e
3231 750 Motorola/IBM PowerPC 750 or 750
3233 At the moment, this command just tells GDB what to name the
3234 special-purpose processor registers. Since almost all the affected
3235 registers are inaccessible to user-level programs, this command is
3236 only useful for remote debugging in its present form.
3240 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3241 more extensive support for HP-UX. Added features include shared
3242 library support, kernel threads and hardware watchpoints for 11.00,
3243 support for HP's ANSI C and C++ compilers, and a compatibility mode
3244 for xdb and dbx commands.
3248 HP's donation includes the new concept of catchpoints, which is a
3249 generalization of the old catch command. On HP-UX, it is now possible
3250 to catch exec, fork, and vfork, as well as library loading.
3252 This means that the existing catch command has changed; its first
3253 argument now specifies the type of catch to be set up. See the
3254 output of "help catch" for a list of catchpoint types.
3256 * Debugging across forks
3258 On HP-UX, you can choose which process to debug when a fork() happens
3263 HP has donated a curses-based terminal user interface (TUI). To get
3264 it, build with --enable-tui. Although this can be enabled for any
3265 configuration, at present it only works for native HP debugging.
3267 * GDB remote protocol additions
3269 A new protocol packet 'X' that writes binary data is now available.
3270 Default behavior is to try 'X', then drop back to 'M' if the stub
3271 fails to respond. The settable variable `remotebinarydownload'
3272 allows explicit control over the use of 'X'.
3274 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3275 full 64-bit address. The command
3277 set remoteaddresssize 32
3279 can be used to revert to the old behaviour. For existing remote stubs
3280 the change should not be noticed, as the additional address information
3283 In order to assist in debugging stubs, you may use the maintenance
3284 command `packet' to send any text string to the stub. For instance,
3286 maint packet heythere
3288 sends the packet "$heythere#<checksum>". Note that it is very easy to
3289 disrupt a debugging session by sending the wrong packet at the wrong
3292 The compare-sections command allows you to compare section data on the
3293 target to what is in the executable file without uploading or
3294 downloading, by comparing CRC checksums.
3296 * Tracing can collect general expressions
3298 You may now collect general expressions at tracepoints. This requires
3299 further additions to the target-side stub; see tracepoint.c and
3300 doc/agentexpr.texi for further details.
3302 * mask-address variable for Mips
3304 For Mips targets, you may control the zeroing of the upper 32 bits of
3305 a 64-bit address by entering `set mask-address on'. This is mainly
3306 of interest to users of embedded R4xxx and R5xxx processors.
3308 * Higher serial baud rates
3310 GDB's serial code now allows you to specify baud rates 57600, 115200,
3311 230400, and 460800 baud. (Note that your host system may not be able
3312 to achieve all of these rates.)
3316 The i960 configuration now includes an initial implementation of a
3317 builtin simulator, contributed by Jim Wilson.
3320 *** Changes in GDB-4.17:
3322 * New native configurations
3324 Alpha GNU/Linux alpha*-*-linux*
3325 Unixware 2.x i[3456]86-unixware2*
3326 Irix 6.x mips*-sgi-irix6*
3327 PowerPC GNU/Linux powerpc-*-linux*
3328 PowerPC Solaris powerpcle-*-solaris*
3329 Sparc GNU/Linux sparc-*-linux*
3330 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3334 Argonaut Risc Chip (ARC) arc-*-*
3335 Hitachi H8/300S h8300*-*-*
3336 Matsushita MN10200 w/simulator mn10200-*-*
3337 Matsushita MN10300 w/simulator mn10300-*-*
3338 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3339 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3340 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3341 Mitsubishi D10V w/simulator d10v-*-*
3342 Mitsubishi M32R/D w/simulator m32r-*-elf*
3343 Tsqware Sparclet sparclet-*-*
3344 NEC V850 w/simulator v850-*-*
3346 * New debugging protocols
3348 ARM with RDI protocol arm*-*-*
3349 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3350 DDB and LSI variants of PMON protocol mips*-*-*
3351 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3352 PowerPC with SDS protocol powerpc{,le}-*-eabi
3353 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3357 All configurations can now understand and use the DWARF 2 debugging
3358 format. The choice is automatic, if the symbol file contains DWARF 2
3363 GDB now includes basic Java language support. This support is
3364 only useful with Java compilers that produce native machine code.
3366 * solib-absolute-prefix and solib-search-path
3368 For SunOS and SVR4 shared libraries, you may now set the prefix for
3369 loading absolute shared library symbol files, and the search path for
3370 locating non-absolute shared library symbol files.
3372 * Live range splitting
3374 GDB can now effectively debug code for which GCC has performed live
3375 range splitting as part of its optimization. See gdb/doc/LRS for
3376 more details on the expected format of the stabs information.
3380 GDB's support for the GNU Hurd, including thread debugging, has been
3381 updated to work with current versions of the Hurd.
3385 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3386 instruction set. ARM GDB automatically detects when Thumb
3387 instructions are in use, and adjusts disassembly and backtracing
3392 GDB's MIPS target configurations now handle the MIP16 16-bit
3397 GDB now includes support for overlays; if an executable has been
3398 linked such that multiple sections are based at the same address, GDB
3399 will decide which section to use for symbolic info. You can choose to
3400 control the decision manually, using overlay commands, or implement
3401 additional target-side support and use "overlay load-target" to bring
3402 in the overlay mapping. Do "help overlay" for more detail.
3406 The command "info symbol <address>" displays information about
3407 the symbol at the specified address.
3411 The standard remote protocol now includes an extension that allows
3412 asynchronous collection and display of trace data. This requires
3413 extensive support in the target-side debugging stub. Tracing mode
3414 includes a new interaction mode in GDB and new commands: see the
3415 file tracepoint.c for more details.
3419 Configurations for embedded MIPS now include a simulator contributed
3420 by Cygnus Solutions. The simulator supports the instruction sets
3421 of most MIPS variants.
3425 Sparc configurations may now include the ERC32 simulator contributed
3426 by the European Space Agency. The simulator is not built into
3427 Sparc targets by default; configure with --enable-sim to include it.
3431 For target configurations that may include multiple variants of a
3432 basic architecture (such as MIPS and SH), you may now set the
3433 architecture explicitly. "set arch" sets, "info arch" lists
3434 the possible architectures.
3436 *** Changes in GDB-4.16:
3438 * New native configurations
3440 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3441 M68K NetBSD m68k-*-netbsd*
3442 PowerPC AIX 4.x powerpc-*-aix*
3443 PowerPC MacOS powerpc-*-macos*
3444 PowerPC Windows NT powerpcle-*-cygwin32
3445 RS/6000 AIX 4.x rs6000-*-aix4*
3449 ARM with RDP protocol arm-*-*
3450 I960 with MON960 i960-*-coff
3451 MIPS VxWorks mips*-*-vxworks*
3452 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3453 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3455 Matra Sparclet sparclet-*-*
3459 The powerpc-eabi configuration now includes the PSIM simulator,
3460 contributed by Andrew Cagney, with assistance from Mike Meissner.
3461 PSIM is a very elaborate model of the PowerPC, including not only
3462 basic instruction set execution, but also details of execution unit
3463 performance and I/O hardware. See sim/ppc/README for more details.
3467 GDB now works with Solaris 2.5.
3469 * Windows 95/NT native
3471 GDB will now work as a native debugger on Windows 95 and Windows NT.
3472 To build it from source, you must use the "gnu-win32" environment,
3473 which uses a DLL to emulate enough of Unix to run the GNU tools.
3474 Further information, binaries, and sources are available at
3475 ftp.cygnus.com, under pub/gnu-win32.
3477 * dont-repeat command
3479 If a user-defined command includes the command `dont-repeat', then the
3480 command will not be repeated if the user just types return. This is
3481 useful if the command is time-consuming to run, so that accidental
3482 extra keystrokes don't run the same command many times.
3484 * Send break instead of ^C
3486 The standard remote protocol now includes an option to send a break
3487 rather than a ^C to the target in order to interrupt it. By default,
3488 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3490 * Remote protocol timeout
3492 The standard remote protocol includes a new variable `remotetimeout'
3493 that allows you to set the number of seconds before GDB gives up trying
3494 to read from the target. The default value is 2.
3496 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3498 By default GDB will automatically keep track of objects as they are
3499 loaded and unloaded by the dynamic linker. By using the command `set
3500 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3501 when shared library events occur, thus allowing you to set breakpoints
3502 in shared libraries which are explicitly loaded by the inferior.
3504 Note this feature does not work on hpux8. On hpux9 you must link
3505 /usr/lib/end.o into your program. This feature should work
3506 automatically on hpux10.
3508 * Irix 5.x hardware watchpoint support
3510 Irix 5 configurations now support the use of hardware watchpoints.
3512 * Mips protocol "SYN garbage limit"
3514 When debugging a Mips target using the `target mips' protocol, you
3515 may set the number of characters that GDB will ignore by setting
3516 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3517 every character. The default value is 1050.
3519 * Recording and replaying remote debug sessions
3521 If you set `remotelogfile' to the name of a file, gdb will write to it
3522 a recording of a remote debug session. This recording may then be
3523 replayed back to gdb using "gdbreplay". See gdbserver/README for
3524 details. This is useful when you have a problem with GDB while doing
3525 remote debugging; you can make a recording of the session and send it
3526 to someone else, who can then recreate the problem.
3528 * Speedups for remote debugging
3530 GDB includes speedups for downloading and stepping MIPS systems using
3531 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3532 and more efficient S-record downloading.
3534 * Memory use reductions and statistics collection
3536 GDB now uses less memory and reports statistics about memory usage.
3537 Try the `maint print statistics' command, for example.
3539 *** Changes in GDB-4.15:
3541 * Psymtabs for XCOFF
3543 The symbol reader for AIX GDB now uses partial symbol tables. This
3544 can greatly improve startup time, especially for large executables.
3546 * Remote targets use caching
3548 Remote targets now use a data cache to speed up communication with the
3549 remote side. The data cache could lead to incorrect results because
3550 it doesn't know about volatile variables, thus making it impossible to
3551 debug targets which use memory mapped I/O devices. `set remotecache
3552 off' turns the the data cache off.
3554 * Remote targets may have threads
3556 The standard remote protocol now includes support for multiple threads
3557 in the target system, using new protocol commands 'H' and 'T'. See
3558 gdb/remote.c for details.
3562 If GDB is configured with `--enable-netrom', then it will include
3563 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3564 acts as though it is a bank of ROM on the target board, but you can
3565 write into it over the network. GDB's support consists only of
3566 support for fast loading into the emulated ROM; to debug, you must use
3567 another protocol, such as standard remote protocol. The usual
3568 sequence is something like
3570 target nrom <netrom-hostname>
3572 target remote <netrom-hostname>:1235
3576 GDB now includes support for the Apple Macintosh, as a host only. It
3577 may be run as either an MPW tool or as a standalone application, and
3578 it can debug through the serial port. All the usual GDB commands are
3579 available, but to the target command, you must supply "serial" as the
3580 device type instead of "/dev/ttyXX". See mpw-README in the main
3581 directory for more information on how to build. The MPW configuration
3582 scripts */mpw-config.in support only a few targets, and only the
3583 mips-idt-ecoff target has been tested.
3587 GDB configuration now uses autoconf. This is not user-visible,
3588 but does simplify configuration and building.
3592 GDB now supports hpux10.
3594 *** Changes in GDB-4.14:
3596 * New native configurations
3598 x86 FreeBSD i[345]86-*-freebsd
3599 x86 NetBSD i[345]86-*-netbsd
3600 NS32k NetBSD ns32k-*-netbsd
3601 Sparc NetBSD sparc-*-netbsd
3605 A29K VxWorks a29k-*-vxworks
3606 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3607 CPU32 EST-300 emulator m68*-*-est*
3608 PowerPC ELF powerpc-*-elf
3611 * Alpha OSF/1 support for procfs
3613 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3614 possible to attach to running processes. As the mounting of the /proc
3615 filesystem is optional on the Alpha, GDB automatically determines
3616 the availability of /proc during startup. This can lead to problems
3617 if /proc is unmounted after GDB has been started.
3619 * Arguments to user-defined commands
3621 User commands may accept up to 10 arguments separated by whitespace.
3622 Arguments are accessed within the user command via $arg0..$arg9. A
3625 print $arg0 + $arg1 + $arg2
3627 To execute the command use:
3630 Defines the command "adder" which prints the sum of its three arguments.
3631 Note the arguments are text substitutions, so they may reference variables,
3632 use complex expressions, or even perform inferior function calls.
3634 * New `if' and `while' commands
3636 This makes it possible to write more sophisticated user-defined
3637 commands. Both commands take a single argument, which is the
3638 expression to evaluate, and must be followed by the commands to
3639 execute, one per line, if the expression is nonzero, the list being
3640 terminated by the word `end'. The `if' command list may include an
3641 `else' word, which causes the following commands to be executed only
3642 if the expression is zero.
3644 * Fortran source language mode
3646 GDB now includes partial support for Fortran 77. It will recognize
3647 Fortran programs and can evaluate a subset of Fortran expressions, but
3648 variables and functions may not be handled correctly. GDB will work
3649 with G77, but does not yet know much about symbols emitted by other
3652 * Better HPUX support
3654 Most debugging facilities now work on dynamic executables for HPPAs
3655 running hpux9 or later. You can attach to running dynamically linked
3656 processes, but by default the dynamic libraries will be read-only, so
3657 for instance you won't be able to put breakpoints in them. To change
3658 that behavior do the following before running the program:
3664 This will cause the libraries to be mapped private and read-write.
3665 To revert to the normal behavior, do this:
3671 You cannot set breakpoints or examine data in the library until after
3672 the library is loaded if the function/data symbols do not have
3675 GDB can now also read debug symbols produced by the HP C compiler on
3676 HPPAs (sorry, no C++, Fortran or 68k support).
3678 * Target byte order now dynamically selectable
3680 You can choose which byte order to use with a target system, via the
3681 commands "set endian big" and "set endian little", and you can see the
3682 current setting by using "show endian". You can also give the command
3683 "set endian auto", in which case GDB will use the byte order
3684 associated with the executable. Currently, only embedded MIPS
3685 configurations support dynamic selection of target byte order.
3687 * New DOS host serial code
3689 This version uses DPMI interrupts to handle buffered I/O, so you
3690 no longer need to run asynctsr when debugging boards connected to
3693 *** Changes in GDB-4.13:
3695 * New "complete" command
3697 This lists all the possible completions for the rest of the line, if it
3698 were to be given as a command itself. This is intended for use by emacs.
3700 * Trailing space optional in prompt
3702 "set prompt" no longer adds a space for you after the prompt you set. This
3703 allows you to set a prompt which ends in a space or one that does not.
3705 * Breakpoint hit counts
3707 "info break" now displays a count of the number of times the breakpoint
3708 has been hit. This is especially useful in conjunction with "ignore"; you
3709 can ignore a large number of breakpoint hits, look at the breakpoint info
3710 to see how many times the breakpoint was hit, then run again, ignoring one
3711 less than that number, and this will get you quickly to the last hit of
3714 * Ability to stop printing at NULL character
3716 "set print null-stop" will cause GDB to stop printing the characters of
3717 an array when the first NULL is encountered. This is useful when large
3718 arrays actually contain only short strings.
3720 * Shared library breakpoints
3722 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3723 breakpoints in shared libraries before the executable is run.
3725 * Hardware watchpoints
3727 There is a new hardware breakpoint for the watch command for sparclite
3728 targets. See gdb/sparclite/hw_breakpoint.note.
3730 Hardware watchpoints are also now supported under GNU/Linux.
3734 Annotations have been added. These are for use with graphical interfaces,
3735 and are still experimental. Currently only gdba.el uses these.
3737 * Improved Irix 5 support
3739 GDB now works properly with Irix 5.2.
3741 * Improved HPPA support
3743 GDB now works properly with the latest GCC and GAS.
3745 * New native configurations
3747 Sequent PTX4 i[34]86-sequent-ptx4
3748 HPPA running OSF/1 hppa*-*-osf*
3749 Atari TT running SVR4 m68*-*-sysv4*
3750 RS/6000 LynxOS rs6000-*-lynxos*
3754 OS/9000 i[34]86-*-os9k
3755 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3758 * Hitachi SH7000 and E7000-PC ICE support
3760 There is now support for communicating with the Hitachi E7000-PC ICE.
3761 This is available automatically when GDB is configured for the SH.
3765 As usual, a variety of small fixes and improvements, both generic
3766 and configuration-specific. See the ChangeLog for more detail.
3768 *** Changes in GDB-4.12:
3770 * Irix 5 is now supported
3774 GDB-4.12 on the HPPA has a number of changes which make it unable
3775 to debug the output from the currently released versions of GCC and
3776 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3777 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3778 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3781 *** Changes in GDB-4.11:
3783 * User visible changes:
3787 The "set remotedebug" option is now consistent between the mips remote
3788 target, remote targets using the gdb-specific protocol, UDI (AMD's
3789 debug protocol for the 29k) and the 88k bug monitor. It is now an
3790 integer specifying a debug level (normally 0 or 1, but 2 means more
3791 debugging info for the mips target).
3793 * DEC Alpha native support
3795 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3796 debug info, but GDB works fairly well with the DEC compiler and should
3797 work with a future GCC release. See the README file for a few
3798 Alpha-specific notes.
3800 * Preliminary thread implementation
3802 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3804 * LynxOS native and target support for 386
3806 This release has been hosted on LynxOS 2.2, and also can be configured
3807 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3810 * Improvements in C++ mangling/demangling.
3812 This release has much better g++ debugging, specifically in name
3813 mangling/demangling, virtual function calls, print virtual table,
3814 call methods, ...etc.
3816 *** Changes in GDB-4.10:
3818 * User visible changes:
3820 Remote debugging using the GDB-specific (`target remote') protocol now
3821 supports the `load' command. This is only useful if you have some
3822 other way of getting the stub to the target system, and you can put it
3823 somewhere in memory where it won't get clobbered by the download.
3825 Filename completion now works.
3827 When run under emacs mode, the "info line" command now causes the
3828 arrow to point to the line specified. Also, "info line" prints
3829 addresses in symbolic form (as well as hex).
3831 All vxworks based targets now support a user settable option, called
3832 vxworks-timeout. This option represents the number of seconds gdb
3833 should wait for responses to rpc's. You might want to use this if
3834 your vxworks target is, perhaps, a slow software simulator or happens
3835 to be on the far side of a thin network line.
3839 This release contains support for using a DEC alpha as a GDB host for
3840 cross debugging. Native alpha debugging is not supported yet.
3843 *** Changes in GDB-4.9:
3847 This is the first GDB release which is accompanied by a matching testsuite.
3848 The testsuite requires installation of dejagnu, which should be available
3849 via ftp from most sites that carry GNU software.
3853 'Cfront' style demangling has had its name changed to 'ARM' style, to
3854 emphasize that it was written from the specifications in the C++ Annotated
3855 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3856 disclaimers, it still generated too much confusion with users attempting to
3857 use gdb with AT&T cfront.
3861 GDB now uses a standard remote interface to a simulator library.
3862 So far, the library contains simulators for the Zilog Z8001/2, the
3863 Hitachi H8/300, H8/500 and Super-H.
3865 * New targets supported
3867 H8/300 simulator h8300-hitachi-hms or h8300hms
3868 H8/500 simulator h8500-hitachi-hms or h8500hms
3869 SH simulator sh-hitachi-hms or sh
3870 Z8000 simulator z8k-zilog-none or z8ksim
3871 IDT MIPS board over serial line mips-idt-ecoff
3873 Cross-debugging to GO32 targets is supported. It requires a custom
3874 version of the i386-stub.c module which is integrated with the
3875 GO32 memory extender.
3877 * New remote protocols
3879 MIPS remote debugging protocol.
3881 * New source languages supported
3883 This version includes preliminary support for Chill, a Pascal like language
3884 used by telecommunications companies. Chill support is also being integrated
3885 into the GNU compiler, but we don't know when it will be publically available.
3888 *** Changes in GDB-4.8:
3890 * HP Precision Architecture supported
3892 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3893 version of this support was available as a set of patches from the
3894 University of Utah. GDB does not support debugging of programs
3895 compiled with the HP compiler, because HP will not document their file
3896 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3897 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3899 Many problems in the preliminary version have been fixed.
3901 * Faster and better demangling
3903 We have improved template demangling and fixed numerous bugs in the GNU style
3904 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3905 character types (wchar_t) are now supported. Demangling of each symbol is now
3906 only done once, and is cached when the symbol table for a file is read in.
3907 This results in a small increase in memory usage for C programs, a moderate
3908 increase in memory usage for C++ programs, and a fantastic speedup in
3911 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3912 from the specifications in the Annotated Reference Manual, which AT&T's
3913 compiler does not actually implement.
3915 * G++ multiple inheritance compiler problem
3917 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3918 inheritance lattices was reworked to properly discover ambiguities. We
3919 recently found an example which causes this new algorithm to fail in a
3920 very subtle way, producing bad debug information for those classes.
3921 The file 'gcc.patch' (in this directory) can be applied to gcc to
3922 circumvent the problem. A future GCC release will contain a complete
3925 The previous G++ debug info problem (mentioned below for the gdb-4.7
3926 release) is fixed in gcc version 2.3.2.
3928 * Improved configure script
3930 The `configure' script will now attempt to guess your system type if
3931 you don't supply a host system type. The old scheme of supplying a
3932 host system triplet is preferable over using this. All the magic is
3933 done in the new `config.guess' script. Examine it for details.
3935 We have also brought our configure script much more in line with the FSF's
3936 version. It now supports the --with-xxx options. In particular,
3937 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3938 The resulting GDB will not be able to read arbitrary object file formats --
3939 only the format ``expected'' to be used on the configured target system.
3940 We hope to make this the default in a future release.
3942 * Documentation improvements
3944 There's new internal documentation on how to modify GDB, and how to
3945 produce clean changes to the code. We implore people to read it
3946 before submitting changes.
3948 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3949 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3950 `info' files are also provided. To build `info' files from scratch,
3951 you will need the latest `makeinfo' release, which will be available in
3952 a future texinfo-X.Y release.
3954 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3955 We're not sure exactly which versions have this problem, but it has
3956 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3957 or better. If that isn't possible, there is a patch in
3958 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3959 around this problem.
3963 GDB now supports array constants that can be used in expressions typed in by
3964 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3965 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3968 The new directory `gdb/sparclite' contains a program that demonstrates
3969 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3971 * New native hosts supported
3973 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3974 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3976 * New targets supported
3978 AMD 29k family via UDI a29k-amd-udi or udi29k
3980 * New file formats supported
3982 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3983 HPUX core files, and SCO 3.2v2 core files.
3987 Attaching to processes now works again; thanks for the many bug reports.
3989 We have also stomped on a bunch of core dumps caused by
3990 printf_filtered("%s") problems.
3992 We eliminated a copyright problem on the rpc and ptrace header files
3993 for VxWorks, which was discovered at the last minute during the 4.7
3994 release. You should now be able to build a VxWorks GDB.
3996 You can now interrupt gdb while an attached process is running. This
3997 will cause the attached process to stop, and give control back to GDB.
3999 We fixed problems caused by using too many file descriptors
4000 for reading symbols from object files and libraries. This was
4001 especially a problem for programs that used many (~100) shared
4004 The `step' command now only enters a subroutine if there is line number
4005 information for the subroutine. Otherwise it acts like the `next'
4006 command. Previously, `step' would enter subroutines if there was
4007 any debugging information about the routine. This avoids problems
4008 when using `cc -g1' on MIPS machines.
4010 * Internal improvements
4012 GDB's internal interfaces have been improved to make it easier to support
4013 debugging of multiple languages in the future.
4015 GDB now uses a common structure for symbol information internally.
4016 Minimal symbols (derived from linkage symbols in object files), partial
4017 symbols (from a quick scan of debug information), and full symbols
4018 contain a common subset of information, making it easier to write
4019 shared code that handles any of them.
4021 * New command line options
4023 We now accept --silent as an alias for --quiet.
4027 The memory-mapped-malloc library is now licensed under the GNU Library
4028 General Public License.
4030 *** Changes in GDB-4.7:
4032 * Host/native/target split
4034 GDB has had some major internal surgery to untangle the support for
4035 hosts and remote targets. Now, when you configure GDB for a remote
4036 target, it will no longer load in all of the support for debugging
4037 local programs on the host. When fully completed and tested, this will
4038 ensure that arbitrary host/target combinations are possible.
4040 The primary conceptual shift is to separate the non-portable code in
4041 GDB into three categories. Host specific code is required any time GDB
4042 is compiled on that host, regardless of the target. Target specific
4043 code relates to the peculiarities of the target, but can be compiled on
4044 any host. Native specific code is everything else: it can only be
4045 built when the host and target are the same system. Child process
4046 handling and core file support are two common `native' examples.
4048 GDB's use of /proc for controlling Unix child processes is now cleaner.
4049 It has been split out into a single module under the `target_ops' vector,
4050 plus two native-dependent functions for each system that uses /proc.
4052 * New hosts supported
4054 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4055 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4056 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4058 * New targets supported
4060 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4061 68030 and CPU32 m68030-*-*, m68332-*-*
4063 * New native hosts supported
4065 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4066 (386bsd is not well tested yet)
4067 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4069 * New file formats supported
4071 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4072 supports reading of `a.out.adobe' object files, which are an a.out
4073 format extended with minimal information about multiple sections.
4077 `show copying' is the same as the old `info copying'.
4078 `show warranty' is the same as `info warrantee'.
4079 These were renamed for consistency. The old commands continue to work.
4081 `info handle' is a new alias for `info signals'.
4083 You can now define pre-command hooks, which attach arbitrary command
4084 scripts to any command. The commands in the hook will be executed
4085 prior to the user's command. You can also create a hook which will be
4086 executed whenever the program stops. See gdb.texinfo.
4090 We now deal with Cfront style name mangling, and can even extract type
4091 info from mangled symbols. GDB can automatically figure out which
4092 symbol mangling style your C++ compiler uses.
4094 Calling of methods and virtual functions has been improved as well.
4098 The crash that occured when debugging Sun Ansi-C compiled binaries is
4099 fixed. This was due to mishandling of the extra N_SO stabs output
4102 We also finally got Ultrix 4.2 running in house, and fixed core file
4103 support, with help from a dozen people on the net.
4105 John M. Farrell discovered that the reason that single-stepping was so
4106 slow on all of the Mips based platforms (primarily SGI and DEC) was
4107 that we were trying to demangle and lookup a symbol used for internal
4108 purposes on every instruction that was being stepped through. Changing
4109 the name of that symbol so that it couldn't be mistaken for a C++
4110 mangled symbol sped things up a great deal.
4112 Rich Pixley sped up symbol lookups in general by getting much smarter
4113 about when C++ symbol mangling is necessary. This should make symbol
4114 completion (TAB on the command line) much faster. It's not as fast as
4115 we'd like, but it's significantly faster than gdb-4.6.
4119 A new user controllable variable 'call_scratch_address' can
4120 specify the location of a scratch area to be used when GDB
4121 calls a function in the target. This is necessary because the
4122 usual method of putting the scratch area on the stack does not work
4123 in systems that have separate instruction and data spaces.
4125 We integrated changes to support the 29k UDI (Universal Debugger
4126 Interface), but discovered at the last minute that we didn't have all
4127 of the appropriate copyright paperwork. We are working with AMD to
4128 resolve this, and hope to have it available soon.
4132 We have sped up the remote serial line protocol, especially for targets
4133 with lots of registers. It now supports a new `expedited status' ('T')
4134 message which can be used in place of the existing 'S' status message.
4135 This allows the remote stub to send only the registers that GDB
4136 needs to make a quick decision about single-stepping or conditional
4137 breakpoints, eliminating the need to fetch the entire register set for
4138 each instruction being stepped through.
4140 The GDB remote serial protocol now implements a write-through cache for
4141 registers, only re-reading the registers if the target has run.
4143 There is also a new remote serial stub for SPARC processors. You can
4144 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4145 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4146 processor with a serial port.
4150 Configure.in files have become much easier to read and modify. A new
4151 `table driven' format makes it more obvious what configurations are
4152 supported, and what files each one uses.
4156 There is a new opcodes library which will eventually contain all of the
4157 disassembly routines and opcode tables. At present, it only contains
4158 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4159 disassembler (binutils/objdump) to share these routines.
4161 The libiberty library is now copylefted under the GNU Library General
4162 Public License. This allows more liberal use, and was done so libg++
4163 can use it. This makes no difference to GDB, since the Library License
4164 grants all the rights from the General Public License.
4168 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4169 reference to the stabs symbol info used by the debugger. It is (as far
4170 as we know) the only published document on this fascinating topic. We
4171 encourage you to read it, compare it to the stabs information on your
4172 system, and send improvements on the document in general (to
4173 bug-gdb@prep.ai.mit.edu).
4175 And, of course, many bugs have been fixed.
4178 *** Changes in GDB-4.6:
4180 * Better support for C++ function names
4182 GDB now accepts as input the "demangled form" of C++ overloaded function
4183 names and member function names, and can do command completion on such names
4184 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4185 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4186 Make use of command completion, it is your friend.
4188 GDB also now accepts a variety of C++ mangled symbol formats. They are
4189 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4190 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4191 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4192 for the list of formats.
4194 * G++ symbol mangling problem
4196 Recent versions of gcc have a bug in how they emit debugging information for
4197 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4198 directory) can be applied to gcc to fix the problem. Alternatively, if you
4199 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4200 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4201 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4204 * New 'maintenance' command
4206 All of the commands related to hacking GDB internals have been moved out of
4207 the main command set, and now live behind the 'maintenance' command. This
4208 can also be abbreviated as 'mt'. The following changes were made:
4210 dump-me -> maintenance dump-me
4211 info all-breakpoints -> maintenance info breakpoints
4212 printmsyms -> maintenance print msyms
4213 printobjfiles -> maintenance print objfiles
4214 printpsyms -> maintenance print psymbols
4215 printsyms -> maintenance print symbols
4217 The following commands are new:
4219 maintenance demangle Call internal GDB demangler routine to
4220 demangle a C++ link name and prints the result.
4221 maintenance print type Print a type chain for a given symbol
4223 * Change to .gdbinit file processing
4225 We now read the $HOME/.gdbinit file before processing the argv arguments
4226 (e.g. reading symbol files or core files). This allows global parameters to
4227 be set, which will apply during the symbol reading. The ./.gdbinit is still
4228 read after argv processing.
4230 * New hosts supported
4232 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4234 GNU/Linux support i386-unknown-linux or linux
4236 We are also including code to support the HP/PA running BSD and HPUX. This
4237 is almost guaranteed not to work, as we didn't have time to test or build it
4238 for this release. We are including it so that the more adventurous (or
4239 masochistic) of you can play with it. We also had major problems with the
4240 fact that the compiler that we got from HP doesn't support the -g option.
4243 * New targets supported
4245 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4247 * More smarts about finding #include files
4249 GDB now remembers the compilation directory for all include files, and for
4250 all files from which C is generated (like yacc and lex sources). This
4251 greatly improves GDB's ability to find yacc/lex sources, and include files,
4252 especially if you are debugging your program from a directory different from
4253 the one that contains your sources.
4255 We also fixed a bug which caused difficulty with listing and setting
4256 breakpoints in include files which contain C code. (In the past, you had to
4257 try twice in order to list an include file that you hadn't looked at before.)
4259 * Interesting infernals change
4261 GDB now deals with arbitrary numbers of sections, where the symbols for each
4262 section must be relocated relative to that section's landing place in the
4263 target's address space. This work was needed to support ELF with embedded
4264 stabs used by Solaris-2.0.
4266 * Bug fixes (of course!)
4268 There have been loads of fixes for the following things:
4269 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4270 i960, stabs, DOS(GO32), procfs, etc...
4272 See the ChangeLog for details.
4274 *** Changes in GDB-4.5:
4276 * New machines supported (host and target)
4278 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4280 SGI Irix-4.x mips-sgi-irix4 or iris4
4282 * New malloc package
4284 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4285 Mmalloc is capable of handling mutiple heaps of memory. It is also
4286 capable of saving a heap to a file, and then mapping it back in later.
4287 This can be used to greatly speedup the startup of GDB by using a
4288 pre-parsed symbol table which lives in a mmalloc managed heap. For
4289 more details, please read mmalloc/mmalloc.texi.
4293 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4294 'help info proc' for details.
4296 * MIPS ecoff symbol table format
4298 The code that reads MIPS symbol table format is now supported on all hosts.
4299 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4302 * File name changes for MS-DOS
4304 Many files in the config directories have been renamed to make it easier to
4305 support GDB on MS-DOSe systems (which have very restrictive file name
4306 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4307 environment) is close to working but has some remaining problems. Note
4308 that debugging of DOS programs is not supported, due to limitations
4309 in the ``operating system'', but it can be used to host cross-debugging.
4311 * Cross byte order fixes
4313 Many fixes have been made to support cross debugging of Sparc and MIPS
4314 targets from hosts whose byte order differs.
4316 * New -mapped and -readnow options
4318 If memory-mapped files are available on your system through the 'mmap'
4319 system call, you can use the -mapped option on the `file' or
4320 `symbol-file' commands to cause GDB to write the symbols from your
4321 program into a reusable file. If the program you are debugging is
4322 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4323 Future GDB debugging sessions will notice the presence of this file,
4324 and will quickly map in symbol information from it, rather than reading
4325 the symbol table from the executable program. Using the '-mapped'
4326 option in a GDB `file' or `symbol-file' command has the same effect as
4327 starting GDB with the '-mapped' command-line option.
4329 You can cause GDB to read the entire symbol table immediately by using
4330 the '-readnow' option with any of the commands that load symbol table
4331 information (or on the GDB command line). This makes the command
4332 slower, but makes future operations faster.
4334 The -mapped and -readnow options are typically combined in order to
4335 build a `fred.syms' file that contains complete symbol information.
4336 A simple GDB invocation to do nothing but build a `.syms' file for future
4339 gdb -batch -nx -mapped -readnow programname
4341 The `.syms' file is specific to the host machine on which GDB is run.
4342 It holds an exact image of GDB's internal symbol table. It cannot be
4343 shared across multiple host platforms.
4345 * longjmp() handling
4347 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4348 siglongjmp() without losing control. This feature has not yet been ported to
4349 all systems. It currently works on many 386 platforms, all MIPS-based
4350 platforms (SGI, DECstation, etc), and Sun3/4.
4354 Preliminary work has been put in to support the new Solaris OS from Sun. At
4355 this time, it can control and debug processes, but it is not capable of
4360 As always, many many bug fixes. The major areas were with g++, and mipsread.
4361 People using the MIPS-based platforms should experience fewer mysterious
4362 crashes and trashed symbol tables.
4364 *** Changes in GDB-4.4:
4366 * New machines supported (host and target)
4368 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4370 BSD Reno on Vax vax-dec-bsd
4371 Ultrix on Vax vax-dec-ultrix
4373 * New machines supported (target)
4375 AMD 29000 embedded, using EBMON a29k-none-none
4379 GDB continues to improve its handling of C++. `References' work better.
4380 The demangler has also been improved, and now deals with symbols mangled as
4381 per the Annotated C++ Reference Guide.
4383 GDB also now handles `stabs' symbol information embedded in MIPS
4384 `ecoff' symbol tables. Since the ecoff format was not easily
4385 extensible to handle new languages such as C++, this appeared to be a
4386 good way to put C++ debugging info into MIPS binaries. This option
4387 will be supported in the GNU C compiler, version 2, when it is
4390 * New features for SVR4
4392 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4393 shared libraries. Debugging dynamically linked programs should present
4394 only minor differences from debugging statically linked programs.
4396 The `info proc' command will print out information about any process
4397 on an SVR4 system (including the one you are debugging). At the moment,
4398 it prints the address mappings of the process.
4400 If you bring up GDB on another SVR4 system, please send mail to
4401 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4403 * Better dynamic linking support in SunOS
4405 Reading symbols from shared libraries which contain debugging symbols
4406 now works properly. However, there remain issues such as automatic
4407 skipping of `transfer vector' code during function calls, which
4408 make it harder to debug code in a shared library, than to debug the
4409 same code linked statically.
4413 GDB is now using the latest `getopt' routines from the FSF. This
4414 version accepts the -- prefix for options with long names. GDB will
4415 continue to accept the old forms (-option and +option) as well.
4416 Various single letter abbreviations for options have been explicity
4417 added to the option table so that they won't get overshadowed in the
4418 future by other options that begin with the same letter.
4422 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4423 Many assorted bugs have been handled. Many more remain to be handled.
4424 See the various ChangeLog files (primarily in gdb and bfd) for details.
4427 *** Changes in GDB-4.3:
4429 * New machines supported (host and target)
4431 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4432 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4433 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4435 * Almost SCO Unix support
4437 We had hoped to support:
4438 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4439 (except for core file support), but we discovered very late in the release
4440 that it has problems with process groups that render gdb unusable. Sorry
4441 about that. I encourage people to fix it and post the fixes.
4443 * Preliminary ELF and DWARF support
4445 GDB can read ELF object files on System V Release 4, and can handle
4446 debugging records for C, in DWARF format, in ELF files. This support
4447 is preliminary. If you bring up GDB on another SVR4 system, please
4448 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4453 GDB now uses the latest `readline' library. One user-visible change
4454 is that two tabs will list possible command completions, which previously
4455 required typing M-? (meta-question mark, or ESC ?).
4459 The `stepi' bug that many of you noticed has been squashed.
4460 Many bugs in C++ have been handled. Many more remain to be handled.
4461 See the various ChangeLog files (primarily in gdb and bfd) for details.
4463 * State of the MIPS world (in case you wondered):
4465 GDB can understand the symbol tables emitted by the compilers
4466 supplied by most vendors of MIPS-based machines, including DEC. These
4467 symbol tables are in a format that essentially nobody else uses.
4469 Some versions of gcc come with an assembler post-processor called
4470 mips-tfile. This program is required if you want to do source-level
4471 debugging of gcc-compiled programs. I believe FSF does not ship
4472 mips-tfile with gcc version 1, but it will eventually come with gcc
4475 Debugging of g++ output remains a problem. g++ version 1.xx does not
4476 really support it at all. (If you're lucky, you should be able to get
4477 line numbers and stack traces to work, but no parameters or local
4478 variables.) With some work it should be possible to improve the
4481 When gcc version 2 is released, you will have somewhat better luck.
4482 However, even then you will get confusing results for inheritance and
4485 We will eventually provide full debugging of g++ output on
4486 DECstations. This will probably involve some kind of stabs-in-ecoff
4487 encapulation, but the details have not been worked out yet.
4490 *** Changes in GDB-4.2:
4492 * Improved configuration
4494 Only one copy of `configure' exists now, and it is not self-modifying.
4495 Porting BFD is simpler.
4499 The `step' and `next' commands now only stop at the first instruction
4500 of a source line. This prevents the multiple stops that used to occur
4501 in switch statements, for-loops, etc. `Step' continues to stop if a
4502 function that has debugging information is called within the line.
4506 Lots of small bugs fixed. More remain.
4508 * New host supported (not target)
4510 Intel 386 PC clone running Mach i386-none-mach
4513 *** Changes in GDB-4.1:
4515 * Multiple source language support
4517 GDB now has internal scaffolding to handle several source languages.
4518 It determines the type of each source file from its filename extension,
4519 and will switch expression parsing and number formatting to match the
4520 language of the function in the currently selected stack frame.
4521 You can also specifically set the language to be used, with
4522 `set language c' or `set language modula-2'.
4526 GDB now has preliminary support for the GNU Modula-2 compiler,
4527 currently under development at the State University of New York at
4528 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4529 continue through the fall of 1991 and into 1992.
4531 Other Modula-2 compilers are currently not supported, and attempting to
4532 debug programs compiled with them will likely result in an error as the
4533 symbol table is read. Feel free to work on it, though!
4535 There are hooks in GDB for strict type checking and range checking,
4536 in the `Modula-2 philosophy', but they do not currently work.
4540 GDB can now write to executable and core files (e.g. patch
4541 a variable's value). You must turn this switch on, specify
4542 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4543 by assigning a new value to a variable. Modifications take
4546 * Automatic SunOS shared library reading
4548 When you run your program, GDB automatically determines where its
4549 shared libraries (if any) have been loaded, and reads their symbols.
4550 The `share' command is no longer needed. This also works when
4551 examining core files.
4555 You can specify the number of lines that the `list' command shows.
4558 * New machines supported (host and target)
4560 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4561 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4562 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4564 * New hosts supported (not targets)
4566 IBM RT/PC: romp-ibm-aix or rtpc
4568 * New targets supported (not hosts)
4570 AMD 29000 embedded with COFF a29k-none-coff
4571 AMD 29000 embedded with a.out a29k-none-aout
4572 Ultracomputer remote kernel debug a29k-nyu-kern
4574 * New remote interfaces
4580 *** Changes in GDB-4.0:
4584 Wide output is wrapped at good places to make the output more readable.
4586 Gdb now supports cross-debugging from a host machine of one type to a
4587 target machine of another type. Communication with the target system
4588 is over serial lines. The ``target'' command handles connecting to the
4589 remote system; the ``load'' command will download a program into the
4590 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4591 also supports debugging of realtime processes running under VxWorks,
4592 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4593 stub on the target system.
4595 New CPUs supported include the AMD 29000 and Intel 960.
4597 GDB now reads object files and symbol tables via a ``binary file''
4598 library, which allows a single copy of GDB to debug programs of multiple
4599 object file types such as a.out and coff.
4601 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4602 refcard.dvi and refcard.ps are available to format it).
4605 * Control-Variable user interface simplified
4607 All variables that control the operation of the debugger can be set
4608 by the ``set'' command, and displayed by the ``show'' command.
4610 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4611 ``Show prompt'' produces the response:
4612 Gdb's prompt is new-gdb=>.
4614 What follows are the NEW set commands. The command ``help set'' will
4615 print a complete list of old and new set commands. ``help set FOO''
4616 will give a longer description of the variable FOO. ``show'' will show
4617 all of the variable descriptions and their current settings.
4619 confirm on/off: Enables warning questions for operations that are
4620 hard to recover from, e.g. rerunning the program while
4621 it is already running. Default is ON.
4623 editing on/off: Enables EMACS style command line editing
4624 of input. Previous lines can be recalled with
4625 control-P, the current line can be edited with control-B,
4626 you can search for commands with control-R, etc.
4629 history filename NAME: NAME is where the gdb command history
4630 will be stored. The default is .gdb_history,
4631 or the value of the environment variable
4634 history size N: The size, in commands, of the command history. The
4635 default is 256, or the value of the environment variable
4638 history save on/off: If this value is set to ON, the history file will
4639 be saved after exiting gdb. If set to OFF, the
4640 file will not be saved. The default is OFF.
4642 history expansion on/off: If this value is set to ON, then csh-like
4643 history expansion will be performed on
4644 command line input. The default is OFF.
4646 radix N: Sets the default radix for input and output. It can be set
4647 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4648 in the current radix, so "set radix 10" is always a no-op.
4650 height N: This integer value is the number of lines on a page. Default
4651 is 24, the current `stty rows'' setting, or the ``li#''
4652 setting from the termcap entry matching the environment
4655 width N: This integer value is the number of characters on a line.
4656 Default is 80, the current `stty cols'' setting, or the ``co#''
4657 setting from the termcap entry matching the environment
4660 Note: ``set screensize'' is obsolete. Use ``set height'' and
4661 ``set width'' instead.
4663 print address on/off: Print memory addresses in various command displays,
4664 such as stack traces and structure values. Gdb looks
4665 more ``symbolic'' if you turn this off; it looks more
4666 ``machine level'' with it on. Default is ON.
4668 print array on/off: Prettyprint arrays. New convenient format! Default
4671 print demangle on/off: Print C++ symbols in "source" form if on,
4674 print asm-demangle on/off: Same, for assembler level printouts
4677 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4680 * Support for Epoch Environment.
4682 The epoch environment is a version of Emacs v18 with windowing. One
4683 new command, ``inspect'', is identical to ``print'', except that if you
4684 are running in the epoch environment, the value is printed in its own
4688 * Support for Shared Libraries
4690 GDB can now debug programs and core files that use SunOS shared libraries.
4691 Symbols from a shared library cannot be referenced
4692 before the shared library has been linked with the program (this
4693 happens after you type ``run'' and before the function main() is entered).
4694 At any time after this linking (including when examining core files
4695 from dynamically linked programs), gdb reads the symbols from each
4696 shared library when you type the ``sharedlibrary'' command.
4697 It can be abbreviated ``share''.
4699 sharedlibrary REGEXP: Load shared object library symbols for files
4700 matching a unix regular expression. No argument
4701 indicates to load symbols for all shared libraries.
4703 info sharedlibrary: Status of loaded shared libraries.
4708 A watchpoint stops execution of a program whenever the value of an
4709 expression changes. Checking for this slows down execution
4710 tremendously whenever you are in the scope of the expression, but is
4711 quite useful for catching tough ``bit-spreader'' or pointer misuse
4712 problems. Some machines such as the 386 have hardware for doing this
4713 more quickly, and future versions of gdb will use this hardware.
4715 watch EXP: Set a watchpoint (breakpoint) for an expression.
4717 info watchpoints: Information about your watchpoints.
4719 delete N: Deletes watchpoint number N (same as breakpoints).
4720 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4721 enable N: Re-enables watchpoint number N (same as breakpoints).
4724 * C++ multiple inheritance
4726 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4729 * C++ exception handling
4731 Gdb now supports limited C++ exception handling. Besides the existing
4732 ability to breakpoint on an exception handler, gdb can breakpoint on
4733 the raising of an exception (before the stack is peeled back to the
4736 catch FOO: If there is a FOO exception handler in the dynamic scope,
4737 set a breakpoint to catch exceptions which may be raised there.
4738 Multiple exceptions (``catch foo bar baz'') may be caught.
4740 info catch: Lists all exceptions which may be caught in the
4741 current stack frame.
4744 * Minor command changes
4746 The command ``call func (arg, arg, ...)'' now acts like the print
4747 command, except it does not print or save a value if the function's result
4748 is void. This is similar to dbx usage.
4750 The ``up'' and ``down'' commands now always print the frame they end up
4751 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4752 frames without printing.
4754 * New directory command
4756 'dir' now adds directories to the FRONT of the source search path.
4757 The path starts off empty. Source files that contain debug information
4758 about the directory in which they were compiled can be found even
4759 with an empty path; Sun CC and GCC include this information. If GDB can't
4760 find your source file in the current directory, type "dir .".
4762 * Configuring GDB for compilation
4764 For normal use, type ``./configure host''. See README or gdb.texinfo
4767 GDB now handles cross debugging. If you are remotely debugging between
4768 two different machines, type ``./configure host -target=targ''.
4769 Host is the machine where GDB will run; targ is the machine
4770 where the program that you are debugging will run.