1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.4
8 ** The "maint set python print-stack on|off" is now deleted.
10 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
11 apply "flag enum"-style pretty-printing to any enum.
13 ** gdb.lookup_symbol can now work when there is no current frame.
15 ** gdb.Symbol now has a 'line' attribute, holding the line number in
16 the source at which the symbol was defined.
18 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
19 method 'value'. The former indicates whether the symbol needs a
20 frame in order to compute its value, and the latter computes the
23 * GDBserver now supports stdio connections.
24 E.g. (gdb) target remote | ssh myhost gdbserver - hello
26 * The binary "gdbtui" can no longer be built or installed.
27 Use "gdb -tui" instead.
29 * GDB will now print "flag" enums specially. A flag enum is one where
30 all the enumerator values have no bits in common when pairwise
31 "and"ed. When printing a value whose type is a flag enum, GDB will
32 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
33 (gdb) print (enum E) 3
36 * The filename part of a linespec will now match trailing components
37 of a source file name. For example, "break gcc/expr.c:1000" will
38 now set a breakpoint in build/gcc/expr.c, but not
41 * The "info proc" and "generate-core-file" commands will now also
42 work on remote targets connected to GDBserver on Linux.
44 * The command "info catch" has been removed. It has been disabled
47 * The "catch exception" and "catch assert" commands now accept
48 a condition at the end of the command, much like the "break"
49 command does. For instance:
51 (gdb) catch exception Constraint_Error if Barrier = True
53 Previously, it was possible to add a condition to such catchpoints,
54 but it had to be done as a second step, after the catchpoint had been
55 created, using the "condition" command.
59 ** "catch load" and "catch unload" can be used to stop when a shared
60 library is loaded or unloaded, respectively.
62 ** "enable count" can be used to auto-disable a breakpoint after
67 Renesas RL78 rl78-*-elf
69 * GDBserver supports evaluation of breakpoint conditions. When
70 support is advertised by GDBserver, GDB may be told to send the
71 breakpoint conditions in bytecode form to GDBserver. GDBserver
72 will only report the breakpoint trigger to GDB when its condition
77 set breakpoint condition-evaluation
78 show breakpoint condition-evaluation
79 Controls whether breakpoint conditions are evaluated by GDB ("gdb") or by
81 This option can improve debugger efficiency depending on the speed of the
86 The z0/z1 breakpoint insertion packets have been extended to carry
87 a list of conditional expressions over to the remote stub depending on the
88 condition evaluation mode. The use of this extension can be controlled
89 via the "set remote conditional-breakpoints-packet" command.
91 *** Changes in GDB 7.4
93 * GDB now handles ambiguous linespecs more consistently; the existing
94 FILE:LINE support has been expanded to other types of linespecs. A
95 breakpoint will now be set on all matching locations in all
96 inferiors, and locations will be added or removed according to
99 * GDB now allows you to skip uninteresting functions and files when
100 stepping with the "skip function" and "skip file" commands.
102 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
103 and "show remote hardware-watchpoint-length-limit". These allows to
104 set or show the maximum length limit (in bytes) of a remote
105 target hardware watchpoint.
107 This allows e.g. to use "unlimited" hardware watchpoints with the
108 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
109 watchpoints are slower than real hardware watchpoints but are
110 significantly faster than gdb software watchpoints.
114 ** The register_pretty_printer function in module gdb.printing now takes
115 an optional `replace' argument. If True, the new printer replaces any
118 ** The "maint set python print-stack on|off" command has been
119 deprecated and will be deleted in GDB 7.5.
120 A new command: "set python print-stack none|full|message" has
121 replaced it. Additionally, the default for "print-stack" is
122 now "message", which just prints the error message without
125 ** A prompt substitution hook (prompt_hook) is now available to the
128 ** A new Python module, gdb.prompt has been added to the GDB Python
129 modules library. This module provides functionality for
130 escape sequences in prompts (used by set/show
131 extended-prompt). These escape sequences are replaced by their
134 ** Python commands and convenience-functions located in
135 'data-directory'/python/gdb/command and
136 'data-directory'/python/gdb/function are now automatically loaded
139 ** Blocks now provide four new attributes. global_block and
140 static_block will return the global and static blocks
141 respectively. is_static and is_global are boolean attributes
142 that indicate if the block is one of those two types.
144 ** Symbols now provide the "type" attribute, the type of the symbol.
146 ** The "gdb.breakpoint" function has been deprecated in favor of
149 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
150 of a function. This class is based on the "finish" command
151 available in the CLI.
153 ** Type objects for struct and union types now allow access to
154 the fields using standard Python dictionary (mapping) methods.
155 For example, "some_type['myfield']" now works, as does
158 ** A new event "gdb.new_objfile" has been added, triggered by loading a
161 ** A new function, "deep_items" has been added to the gdb.types
162 module in the GDB Python modules library. This function returns
163 an iterator over the fields of a struct or union type. Unlike
164 the standard Python "iteritems" method, it will recursively traverse
165 any anonymous fields.
169 ** "*stopped" events can report several new "reason"s, such as
172 ** Breakpoint changes are now notified using new async records, like
173 "=breakpoint-modified".
175 ** New command -ada-task-info.
177 * libthread-db-search-path now supports two special values: $sdir and $pdir.
178 $sdir specifies the default system locations of shared libraries.
179 $pdir specifies the directory where the libpthread used by the application
182 GDB no longer looks in $sdir and $pdir after it has searched the directories
183 mentioned in libthread-db-search-path. If you want to search those
184 directories, they must be specified in libthread-db-search-path.
185 The default value of libthread-db-search-path on GNU/Linux and Solaris
186 systems is now "$sdir:$pdir".
188 $pdir is not supported by gdbserver, it is currently ignored.
189 $sdir is supported by gdbserver.
191 * New configure option --with-iconv-bin.
192 When using the internationalization support like the one in the GNU C
193 library, GDB will invoke the "iconv" program to get a list of supported
194 character sets. If this program lives in a non-standard location, one can
195 use this option to specify where to find it.
197 * When natively debugging programs on PowerPC BookE processors running
198 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
199 watchpoints, which specify a mask in addition to an address to watch.
200 The mask specifies that some bits of an address (the bits which are
201 reset in the mask) should be ignored when matching the address accessed
202 by the inferior against the watchpoint address. See the "PowerPC Embedded"
203 section in the user manual for more details.
205 * The new option --once causes GDBserver to stop listening for connections once
206 the first connection is made. The listening port used by GDBserver will
207 become available after that.
209 * New commands "info macros" and "alias" have been added.
211 * New function parameters suffix @entry specifies value of function parameter
212 at the time the function got called. Entry values are available only since
218 "!" is now an alias of the "shell" command.
219 Note that no space is needed between "!" and SHELL COMMAND.
223 watch EXPRESSION mask MASK_VALUE
224 The watch command now supports the mask argument which allows creation
225 of masked watchpoints, if the current architecture supports this feature.
227 info auto-load-scripts [REGEXP]
228 This command was formerly named "maintenance print section-scripts".
229 It is now generally useful and is no longer a maintenance-only command.
231 info macro [-all] [--] MACRO
232 The info macro command has new options `-all' and `--'. The first for
233 printing all definitions of a macro. The second for explicitly specifying
234 the end of arguments and the beginning of the macro name in case the macro
235 name starts with a hyphen.
237 collect[/s] EXPRESSIONS
238 The tracepoint collect command now takes an optional modifier "/s"
239 that directs it to dereference pointer-to-character types and
240 collect the bytes of memory up to a zero byte. The behavior is
241 similar to what you see when you use the regular print command on a
242 string. An optional integer following the "/s" sets a bound on the
243 number of bytes that will be collected.
246 The trace start command now interprets any supplied arguments as a
247 note to be recorded with the trace run, with an effect similar to
248 setting the variable trace-notes.
251 The trace stop command now interprets any arguments as a note to be
252 mentioned along with the tstatus report that the trace was stopped
253 with a command. The effect is similar to setting the variable
256 * Tracepoints can now be enabled and disabled at any time after a trace
257 experiment has been started using the standard "enable" and "disable"
258 commands. It is now possible to start a trace experiment with no enabled
259 tracepoints; GDB will display a warning, but will allow the experiment to
260 begin, assuming that tracepoints will be enabled as needed while the trace
263 * Fast tracepoints on 32-bit x86-architectures can now be placed at
264 locations with 4-byte instructions, when they were previously
265 limited to locations with instructions of 5 bytes or longer.
271 Set the GDB prompt, and allow escape sequences to be inserted to
272 display miscellaneous information (see 'help set extended-prompt'
273 for the list of sequences). This prompt (and any information
274 accessed through the escape sequences) is updated every time the
277 set print entry-values (both|compact|default|if-needed|no|only|preferred)
278 show print entry-values
279 Set printing of frame argument values at function entry. In some cases
280 GDB can determine the value of function argument which was passed by the
281 function caller, even if the value was modified inside the called function.
283 set debug entry-values
284 show debug entry-values
285 Control display of debugging info for determining frame argument values at
286 function entry and virtual tail call frames.
288 set basenames-may-differ
289 show basenames-may-differ
290 Set whether a source file may have multiple base names.
291 (A "base name" is the name of a file with the directory part removed.
292 Example: The base name of "/home/user/hello.c" is "hello.c".)
293 If set, GDB will canonicalize file names (e.g., expand symlinks)
294 before comparing them. Canonicalization is an expensive operation,
295 but it allows the same file be known by more than one base name.
296 If not set (the default), all source files are assumed to have just
297 one base name, and gdb will do file name comparisons more efficiently.
303 Set a user name and notes for the current and any future trace runs.
304 This is useful for long-running and/or disconnected traces, to
305 inform others (or yourself) as to who is running the trace, supply
306 contact information, or otherwise explain what is going on.
309 show trace-stop-notes
310 Set a note attached to the trace run, that is displayed when the
311 trace has been stopped by a tstop command. This is useful for
312 instance as an explanation, if you are stopping a trace run that was
313 started by someone else.
319 Dynamically enable a tracepoint in a started trace experiment.
323 Dynamically disable a tracepoint in a started trace experiment.
327 Set the user and notes of the trace run.
331 Query the current status of a tracepoint.
335 Query the minimum length of instruction at which a fast tracepoint may
338 * Dcache size (number of lines) and line-size are now runtime-configurable
339 via "set dcache line" and "set dcache line-size" commands.
343 Texas Instruments TMS320C6x tic6x-*-*
347 Renesas RL78 rl78-*-elf
349 *** Changes in GDB 7.3.1
351 * The build failure for NetBSD and OpenBSD targets have now been fixed.
353 *** Changes in GDB 7.3
355 * GDB has a new command: "thread find [REGEXP]".
356 It finds the thread id whose name, target id, or thread extra info
357 matches the given regular expression.
359 * The "catch syscall" command now works on mips*-linux* targets.
361 * The -data-disassemble MI command now supports modes 2 and 3 for
362 dumping the instruction opcodes.
364 * New command line options
366 -data-directory DIR Specify DIR as the "data-directory".
367 This is mostly for testing purposes.
369 * The "maint set python auto-load on|off" command has been renamed to
370 "set auto-load-scripts on|off".
372 * GDB has a new command: "set directories".
373 It is like the "dir" command except that it replaces the
374 source path list instead of augmenting it.
376 * GDB now understands thread names.
378 On GNU/Linux, "info threads" will display the thread name as set by
379 prctl or pthread_setname_np.
381 There is also a new command, "thread name", which can be used to
382 assign a name internally for GDB to display.
385 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
386 has been integrated into GDB.
390 ** The function gdb.Write now accepts an optional keyword 'stream'.
391 This keyword, when provided, will direct the output to either
392 stdout, stderr, or GDB's logging output.
394 ** Parameters can now be be sub-classed in Python, and in particular
395 you may implement the get_set_doc and get_show_doc functions.
396 This improves how Parameter set/show documentation is processed
397 and allows for more dynamic content.
399 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
400 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
401 have an is_valid method.
403 ** Breakpoints can now be sub-classed in Python, and in particular
404 you may implement a 'stop' function that is executed each time
405 the inferior reaches that breakpoint.
407 ** New function gdb.lookup_global_symbol looks up a global symbol.
409 ** GDB values in Python are now callable if the value represents a
410 function. For example, if 'some_value' represents a function that
411 takes two integer parameters and returns a value, you can call
412 that function like so:
414 result = some_value (10,20)
416 ** Module gdb.types has been added.
417 It contains a collection of utilities for working with gdb.Types objects:
418 get_basic_type, has_field, make_enum_dict.
420 ** Module gdb.printing has been added.
421 It contains utilities for writing and registering pretty-printers.
422 New classes: PrettyPrinter, SubPrettyPrinter,
423 RegexpCollectionPrettyPrinter.
424 New function: register_pretty_printer.
426 ** New commands "info pretty-printers", "enable pretty-printer" and
427 "disable pretty-printer" have been added.
429 ** gdb.parameter("directories") is now available.
431 ** New function gdb.newest_frame returns the newest frame in the
434 ** The gdb.InferiorThread class has a new "name" attribute. This
435 holds the thread's name.
437 ** Python Support for Inferior events.
438 Python scripts can add observers to be notified of events
439 occurring in the process being debugged.
440 The following events are currently supported:
441 - gdb.events.cont Continue event.
442 - gdb.events.exited Inferior exited event.
443 - gdb.events.stop Signal received, and Breakpoint hit events.
447 ** GDB now puts template parameters in scope when debugging in an
448 instantiation. For example, if you have:
450 template<int X> int func (void) { return X; }
452 then if you step into func<5>, "print X" will show "5". This
453 feature requires proper debuginfo support from the compiler; it
454 was added to GCC 4.5.
456 ** The motion commands "next", "finish", "until", and "advance" now
457 work better when exceptions are thrown. In particular, GDB will
458 no longer lose control of the inferior; instead, the GDB will
459 stop the inferior at the point at which the exception is caught.
460 This functionality requires a change in the exception handling
461 code that was introduced in GCC 4.5.
463 * GDB now follows GCC's rules on accessing volatile objects when
464 reading or writing target state during expression evaluation.
465 One notable difference to prior behavior is that "print x = 0"
466 no longer generates a read of x; the value of the assignment is
467 now always taken directly from the value being assigned.
469 * GDB now has some support for using labels in the program's source in
470 linespecs. For instance, you can use "advance label" to continue
471 execution to a label.
473 * GDB now has support for reading and writing a new .gdb_index
474 section. This section holds a fast index of DWARF debugging
475 information and can be used to greatly speed up GDB startup and
476 operation. See the documentation for `save gdb-index' for details.
478 * The "watch" command now accepts an optional "-location" argument.
479 When used, this causes GDB to watch the memory referred to by the
480 expression. Such a watchpoint is never deleted due to it going out
483 * GDB now supports thread debugging of core dumps on GNU/Linux.
485 GDB now activates thread debugging using the libthread_db library
486 when debugging GNU/Linux core dumps, similarly to when debugging
487 live processes. As a result, when debugging a core dump file, GDB
488 is now able to display pthread_t ids of threads. For example, "info
489 threads" shows the same output as when debugging the process when it
490 was live. In earlier releases, you'd see something like this:
493 * 1 LWP 6780 main () at main.c:10
495 While now you see this:
498 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
500 It is also now possible to inspect TLS variables when debugging core
503 When debugging a core dump generated on a machine other than the one
504 used to run GDB, you may need to point GDB at the correct
505 libthread_db library with the "set libthread-db-search-path"
506 command. See the user manual for more details on this command.
508 * When natively debugging programs on PowerPC BookE processors running
509 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
510 which stop execution of the inferior whenever it executes an instruction
511 at any address within the specified range. See the "PowerPC Embedded"
512 section in the user manual for more details.
514 * New features in the GDB remote stub, GDBserver
516 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
517 and i686 LynxOS (version 5.x).
519 ** GDBserver is now supported on Blackfin Linux.
521 * New native configurations
523 ia64 HP-UX ia64-*-hpux*
527 Analog Devices, Inc. Blackfin Processor bfin-*
529 * Ada task switching is now supported on sparc-elf targets when
530 debugging a program using the Ravenscar Profile. For more information,
531 see the "Tasking Support when using the Ravenscar Profile" section
532 in the GDB user manual.
534 * Guile support was removed.
536 * New features in the GNU simulator
538 ** The --map-info flag lists all known core mappings.
540 ** CFI flashes may be simulated via the "cfi" device.
542 *** Changes in GDB 7.2
544 * Shared library support for remote targets by default
546 When GDB is configured for a generic, non-OS specific target, like
547 for example, --target=arm-eabi or one of the many *-*-elf targets,
548 GDB now queries remote stubs for loaded shared libraries using the
549 `qXfer:libraries:read' packet. Previously, shared library support
550 was always disabled for such configurations.
554 ** Argument Dependent Lookup (ADL)
556 In C++ ADL lookup directs function search to the namespaces of its
557 arguments even if the namespace has not been imported.
567 Here the compiler will search for `foo' in the namespace of 'b'
568 and find A::foo. GDB now supports this. This construct is commonly
569 used in the Standard Template Library for operators.
571 ** Improved User Defined Operator Support
573 In addition to member operators, GDB now supports lookup of operators
574 defined in a namespace and imported with a `using' directive, operators
575 defined in the global scope, operators imported implicitly from an
576 anonymous namespace, and the ADL operators mentioned in the previous
578 GDB now also supports proper overload resolution for all the previously
579 mentioned flavors of operators.
581 ** static const class members
583 Printing of static const class members that are initialized in the
584 class definition has been fixed.
586 * Windows Thread Information Block access.
588 On Windows targets, GDB now supports displaying the Windows Thread
589 Information Block (TIB) structure. This structure is visible either
590 by using the new command `info w32 thread-information-block' or, by
591 dereferencing the new convenience variable named `$_tlb', a
592 thread-specific pointer to the TIB. This feature is also supported
593 when remote debugging using GDBserver.
597 Static tracepoints are calls in the user program into a tracing
598 library. One such library is a port of the LTTng kernel tracer to
599 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
600 When debugging with GDBserver, GDB now supports combining the GDB
601 tracepoint machinery with such libraries. For example: the user can
602 use GDB to probe a static tracepoint marker (a call from the user
603 program into the tracing library) with the new "strace" command (see
604 "New commands" below). This creates a "static tracepoint" in the
605 breakpoint list, that can be manipulated with the same feature set
606 as fast and regular tracepoints. E.g., collect registers, local and
607 global variables, collect trace state variables, and define
608 tracepoint conditions. In addition, the user can collect extra
609 static tracepoint marker specific data, by collecting the new
610 $_sdata internal variable. When analyzing the trace buffer, you can
611 inspect $_sdata like any other variable available to GDB. For more
612 information, see the "Tracepoints" chapter in GDB user manual. New
613 remote packets have been defined to support static tracepoints, see
614 the "New remote packets" section below.
616 * Better reconstruction of tracepoints after disconnected tracing
618 GDB will attempt to download the original source form of tracepoint
619 definitions when starting a trace run, and then will upload these
620 upon reconnection to the target, resulting in a more accurate
621 reconstruction of the tracepoints that are in use on the target.
625 You can now exercise direct control over the ways that GDB can
626 affect your program. For instance, you can disallow the setting of
627 breakpoints, so that the program can run continuously (assuming
628 non-stop mode). In addition, the "observer" variable is available
629 to switch all of the different controls; in observer mode, GDB
630 cannot affect the target's behavior at all, which is useful for
631 tasks like diagnosing live systems in the field.
633 * The new convenience variable $_thread holds the number of the
640 Return the address of the Windows Thread Information Block of a given thread.
644 In response to several of the tracepoint packets, the target may now
645 also respond with a number of intermediate `qRelocInsn' request
646 packets before the final result packet, to have GDB handle
647 relocating an instruction to execute at a different address. This
648 is particularly useful for stubs that support fast tracepoints. GDB
649 reports support for this feature in the qSupported packet.
653 List static tracepoint markers in the target program.
657 List static tracepoint markers at a given address in the target
660 qXfer:statictrace:read
662 Read the static trace data collected (by a `collect $_sdata'
663 tracepoint action). The remote stub reports support for this packet
664 to gdb's qSupported query.
668 Send the current settings of GDB's permission flags.
672 Send part of the source (textual) form of a tracepoint definition,
673 which includes location, conditional, and action list.
675 * The source command now accepts a -s option to force searching for the
676 script in the source search path even if the script name specifies
679 * New features in the GDB remote stub, GDBserver
681 - GDBserver now support tracepoints (including fast tracepoints, and
682 static tracepoints). The feature is currently supported by the
683 i386-linux and amd64-linux builds. See the "Tracepoints support
684 in gdbserver" section in the manual for more information.
686 GDBserver JIT compiles the tracepoint's conditional agent
687 expression bytecode into native code whenever possible for low
688 overhead dynamic tracepoints conditionals. For such tracepoints,
689 an expression that examines program state is evaluated when the
690 tracepoint is reached, in order to determine whether to capture
691 trace data. If the condition is simple and false, processing the
692 tracepoint finishes very quickly and no data is gathered.
694 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
695 for static tracepoints support.
697 - GDBserver now supports x86_64 Windows 64-bit debugging.
699 * GDB now sends xmlRegisters= in qSupported packet to indicate that
700 it understands register description.
702 * The --batch flag now disables pagination and queries.
704 * X86 general purpose registers
706 GDB now supports reading/writing byte, word and double-word x86
707 general purpose registers directly. This means you can use, say,
708 $ah or $ax to refer, respectively, to the byte register AH and
709 16-bit word register AX that are actually portions of the 32-bit
710 register EAX or 64-bit register RAX.
712 * The `commands' command now accepts a range of breakpoints to modify.
713 A plain `commands' following a command that creates multiple
714 breakpoints affects all the breakpoints set by that command. This
715 applies to breakpoints set by `rbreak', and also applies when a
716 single `break' command creates multiple breakpoints (e.g.,
717 breakpoints on overloaded c++ functions).
719 * The `rbreak' command now accepts a filename specification as part of
720 its argument, limiting the functions selected by the regex to those
721 in the specified file.
723 * Support for remote debugging Windows and SymbianOS shared libraries
724 from Unix hosts has been improved. Non Windows GDB builds now can
725 understand target reported file names that follow MS-DOS based file
726 system semantics, such as file names that include drive letters and
727 use the backslash character as directory separator. This makes it
728 possible to transparently use the "set sysroot" and "set
729 solib-search-path" on Unix hosts to point as host copies of the
730 target's shared libraries. See the new command "set
731 target-file-system-kind" described below, and the "Commands to
732 specify files" section in the user manual for more information.
736 eval template, expressions...
737 Convert the values of one or more expressions under the control
738 of the string template to a command line, and call it.
740 set target-file-system-kind unix|dos-based|auto
741 show target-file-system-kind
742 Set or show the assumed file system kind for target reported file
745 save breakpoints <filename>
746 Save all current breakpoint definitions to a file suitable for use
747 in a later debugging session. To read the saved breakpoint
748 definitions, use the `source' command.
750 `save tracepoints' is a new alias for `save-tracepoints'. The latter
753 info static-tracepoint-markers
754 Display information about static tracepoint markers in the target.
756 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
757 Define a static tracepoint by probing a marker at the given
758 function, line, address, or marker ID.
762 Enable and disable observer mode.
764 set may-write-registers on|off
765 set may-write-memory on|off
766 set may-insert-breakpoints on|off
767 set may-insert-tracepoints on|off
768 set may-insert-fast-tracepoints on|off
769 set may-interrupt on|off
770 Set individual permissions for GDB effects on the target. Note that
771 some of these settings can have undesirable or surprising
772 consequences, particularly when changed in the middle of a session.
773 For instance, disabling the writing of memory can prevent
774 breakpoints from being inserted, cause single-stepping to fail, or
775 even crash your program, if you disable after breakpoints have been
776 inserted. However, GDB should not crash.
778 set record memory-query on|off
779 show record memory-query
780 Control whether to stop the inferior if memory changes caused
781 by an instruction cannot be recorded.
786 The disassemble command now supports "start,+length" form of two arguments.
790 ** GDB now provides a new directory location, called the python directory,
791 where Python scripts written for GDB can be installed. The location
792 of that directory is <data-directory>/python, where <data-directory>
793 is the GDB data directory. For more details, see section `Scripting
794 GDB using Python' in the manual.
796 ** The GDB Python API now has access to breakpoints, symbols, symbol
797 tables, program spaces, inferiors, threads and frame's code blocks.
798 Additionally, GDB Parameters can now be created from the API, and
799 manipulated via set/show in the CLI.
801 ** New functions gdb.target_charset, gdb.target_wide_charset,
802 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
804 ** New exception gdb.GdbError.
806 ** Pretty-printers are now also looked up in the current program space.
808 ** Pretty-printers can now be individually enabled and disabled.
810 ** GDB now looks for names of Python scripts to auto-load in a
811 special section named `.debug_gdb_scripts', in addition to looking
812 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
814 * Tracepoint actions were unified with breakpoint commands. In particular,
815 there are no longer differences in "info break" output for breakpoints and
816 tracepoints and the "commands" command can be used for both tracepoints and
821 ARM Symbian arm*-*-symbianelf*
823 * D language support.
824 GDB now supports debugging programs written in the D programming
827 * GDB now supports the extended ptrace interface for PowerPC which is
828 available since Linux kernel version 2.6.34. This automatically enables
829 any hardware breakpoints and additional hardware watchpoints available in
830 the processor. The old ptrace interface exposes just one hardware
831 watchpoint and no hardware breakpoints.
833 * GDB is now able to use the Data Value Compare (DVC) register available on
834 embedded PowerPC processors to implement in hardware simple watchpoint
835 conditions of the form:
837 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
839 This works in native GDB running on Linux kernels with the extended ptrace
840 interface mentioned above.
842 *** Changes in GDB 7.1
848 GDB now supports importing of namespaces in C++. This enables the
849 user to inspect variables from imported namespaces. Support for
850 namepace aliasing has also been added. So, if a namespace is
851 aliased in the current scope (e.g. namepace C=A; ) the user can
852 print variables using the alias (e.g. (gdb) print C::x).
856 All known bugs relating to the printing of virtual base class were
857 fixed. It is now possible to call overloaded static methods using a
862 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
863 and reinterpret_cast<> are now handled by the C++ expression parser.
867 Xilinx MicroBlaze microblaze-*-*
872 Xilinx MicroBlaze microblaze
875 * Multi-program debugging.
877 GDB now has support for multi-program (a.k.a. multi-executable or
878 multi-exec) debugging. This allows for debugging multiple inferiors
879 simultaneously each running a different program under the same GDB
880 session. See "Debugging Multiple Inferiors and Programs" in the
881 manual for more information. This implied some user visible changes
882 in the multi-inferior support. For example, "info inferiors" now
883 lists inferiors that are not running yet or that have exited
884 already. See also "New commands" and "New options" below.
886 * New tracing features
888 GDB's tracepoint facility now includes several new features:
890 ** Trace state variables
892 GDB tracepoints now include support for trace state variables, which
893 are variables managed by the target agent during a tracing
894 experiment. They are useful for tracepoints that trigger each
895 other, so for instance one tracepoint can count hits in a variable,
896 and then a second tracepoint has a condition that is true when the
897 count reaches a particular value. Trace state variables share the
898 $-syntax of GDB convenience variables, and can appear in both
899 tracepoint actions and condition expressions. Use the "tvariable"
900 command to create, and "info tvariables" to view; see "Trace State
901 Variables" in the manual for more detail.
905 GDB now includes an option for defining fast tracepoints, which
906 targets may implement more efficiently, such as by installing a jump
907 into the target agent rather than a trap instruction. The resulting
908 speedup can be by two orders of magnitude or more, although the
909 tradeoff is that some program locations on some target architectures
910 might not allow fast tracepoint installation, for instance if the
911 instruction to be replaced is shorter than the jump. To request a
912 fast tracepoint, use the "ftrace" command, with syntax identical to
913 the regular trace command.
915 ** Disconnected tracing
917 It is now possible to detach GDB from the target while it is running
918 a trace experiment, then reconnect later to see how the experiment
919 is going. In addition, a new variable disconnected-tracing lets you
920 tell the target agent whether to continue running a trace if the
921 connection is lost unexpectedly.
925 GDB now has the ability to save the trace buffer into a file, and
926 then use that file as a target, similarly to you can do with
927 corefiles. You can select trace frames, print data that was
928 collected in them, and use tstatus to display the state of the
929 tracing run at the moment that it was saved. To create a trace
930 file, use "tsave <filename>", and to use it, do "target tfile
933 ** Circular trace buffer
935 You can ask the target agent to handle the trace buffer as a
936 circular buffer, discarding the oldest trace frames to make room for
937 newer ones, by setting circular-trace-buffer to on. This feature may
938 not be available for all target agents.
943 The disassemble command, when invoked with two arguments, now requires
944 the arguments to be comma-separated.
947 The info variables command now displays variable definitions. Files
948 which only declare a variable are not shown.
951 The source command is now capable of sourcing Python scripts.
952 This feature is dependent on the debugger being build with Python
955 Related to this enhancement is also the introduction of a new command
956 "set script-extension" (see below).
958 * New commands (for set/show, see "New options" below)
960 record save [<FILENAME>]
961 Save a file (in core file format) containing the process record
962 execution log for replay debugging at a later time.
964 record restore <FILENAME>
965 Restore the process record execution log that was saved at an
966 earlier time, for replay debugging.
968 add-inferior [-copies <N>] [-exec <FILENAME>]
971 clone-inferior [-copies <N>] [ID]
972 Make a new inferior ready to execute the same program another
978 maint info program-spaces
979 List the program spaces loaded into GDB.
981 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
982 show remote interrupt-sequence
983 Allow the user to select one of ^C, a BREAK signal or BREAK-g
984 as the sequence to the remote target in order to interrupt the execution.
985 Ctrl-C is a default. Some system prefers BREAK which is high level of
986 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
987 Magic SysRq g. It is BREAK signal and character 'g'.
989 set remote interrupt-on-connect [on | off]
990 show remote interrupt-on-connect
991 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
992 remote target when gdb connects to it. This is needed when you debug
995 set remotebreak [on | off]
997 Deprecated. Use "set/show remote interrupt-sequence" instead.
999 tvariable $NAME [ = EXP ]
1000 Create or modify a trace state variable.
1003 List trace state variables and their values.
1005 delete tvariable $NAME ...
1006 Delete one or more trace state variables.
1009 Evaluate the given expressions without collecting anything into the
1010 trace buffer. (Valid in tracepoint actions only.)
1012 ftrace FN / FILE:LINE / *ADDR
1013 Define a fast tracepoint at the given function, line, or address.
1015 * New expression syntax
1017 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1018 GDB now parses 0b101010 identically with 42.
1022 set follow-exec-mode new|same
1023 show follow-exec-mode
1024 Control whether GDB reuses the same inferior across an exec call or
1025 creates a new one. This is useful to be able to restart the old
1026 executable after the inferior having done an exec call.
1028 set default-collect EXPR, ...
1029 show default-collect
1030 Define a list of expressions to be collected at each tracepoint.
1031 This is a useful way to ensure essential items are not overlooked,
1032 such as registers or a critical global variable.
1034 set disconnected-tracing
1035 show disconnected-tracing
1036 If set to 1, the target is instructed to continue tracing if it
1037 loses its connection to GDB. If 0, the target is to stop tracing
1040 set circular-trace-buffer
1041 show circular-trace-buffer
1042 If set to on, the target is instructed to use a circular trace buffer
1043 and discard the oldest trace frames instead of stopping the trace due
1044 to a full trace buffer. If set to off, the trace stops when the buffer
1045 fills up. Some targets may not support this.
1047 set script-extension off|soft|strict
1048 show script-extension
1049 If set to "off", the debugger does not perform any script language
1050 recognition, and all sourced files are assumed to be GDB scripts.
1051 If set to "soft" (the default), files are sourced according to
1052 filename extension, falling back to GDB scripts if the first
1054 If set to "strict", files are sourced according to filename extension.
1056 set ada trust-PAD-over-XVS on|off
1057 show ada trust-PAD-over-XVS
1058 If off, activate a workaround against a bug in the debugging information
1059 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1060 the GCC sources for more information about the GNAT encoding and
1061 PAD types in particular). It is always safe to set this option to
1062 off, but this introduces a slight performance penalty. The default
1065 * Python API Improvements
1067 ** GDB provides the new class gdb.LazyString. This is useful in
1068 some pretty-printing cases. The new method gdb.Value.lazy_string
1069 provides a simple way to create objects of this type.
1071 ** The fields returned by gdb.Type.fields now have an
1072 `is_base_class' attribute.
1074 ** The new method gdb.Type.range returns the range of an array type.
1076 ** The new method gdb.parse_and_eval can be used to parse and
1077 evaluate an expression.
1079 * New remote packets
1082 Define a trace state variable.
1085 Get the current value of a trace state variable.
1088 Set desired tracing behavior upon disconnection.
1091 Set the trace buffer to be linear or circular.
1094 Get data about the tracepoints currently in use.
1098 Process record now works correctly with hardware watchpoints.
1100 Multiple bug fixes have been made to the mips-irix port, making it
1101 much more reliable. In particular:
1102 - Debugging threaded applications is now possible again. Previously,
1103 GDB would hang while starting the program, or while waiting for
1104 the program to stop at a breakpoint.
1105 - Attaching to a running process no longer hangs.
1106 - An error occurring while loading a core file has been fixed.
1107 - Changing the value of the PC register now works again. This fixes
1108 problems observed when using the "jump" command, or when calling
1109 a function from GDB, or even when assigning a new value to $pc.
1110 - With the "finish" and "return" commands, the return value for functions
1111 returning a small array is now correctly printed.
1112 - It is now possible to break on shared library code which gets executed
1113 during a shared library init phase (code executed while executing
1114 their .init section). Previously, the breakpoint would have no effect.
1115 - GDB is now able to backtrace through the signal handler for
1116 non-threaded programs.
1118 PIE (Position Independent Executable) programs debugging is now supported.
1119 This includes debugging execution of PIC (Position Independent Code) shared
1120 libraries although for that, it should be possible to run such libraries as an
1123 *** Changes in GDB 7.0
1125 * GDB now has an interface for JIT compilation. Applications that
1126 dynamically generate code can create symbol files in memory and register
1127 them with GDB. For users, the feature should work transparently, and
1128 for JIT developers, the interface is documented in the GDB manual in the
1129 "JIT Compilation Interface" chapter.
1131 * Tracepoints may now be conditional. The syntax is as for
1132 breakpoints; either an "if" clause appended to the "trace" command,
1133 or the "condition" command is available. GDB sends the condition to
1134 the target for evaluation using the same bytecode format as is used
1135 for tracepoint actions.
1137 * The disassemble command now supports: an optional /r modifier, print the
1138 raw instructions in hex as well as in symbolic form, and an optional /m
1139 modifier to print mixed source+assembly.
1141 * Process record and replay
1143 In a architecture environment that supports ``process record and
1144 replay'', ``process record and replay'' target can record a log of
1145 the process execution, and replay it with both forward and reverse
1148 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1149 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1150 set execution-direction {forward|reverse}, for targets that support
1153 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1154 feature is available with a native GDB running on kernel version
1157 * GDB now has support for multi-byte and wide character sets on the
1158 target. Strings whose character type is wchar_t, char16_t, or
1159 char32_t are now correctly printed. GDB supports wide- and unicode-
1160 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1161 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1162 `printf'. This feature requires iconv to work properly; if your
1163 system does not have a working iconv, GDB can use GNU libiconv. See
1164 the installation instructions for more information.
1166 * GDB now supports automatic retrieval of shared library files from
1167 remote targets. To use this feature, specify a system root that begins
1168 with the `remote:' prefix, either via the `set sysroot' command or via
1169 the `--with-sysroot' configure-time option.
1171 * "info sharedlibrary" now takes an optional regex of libraries to show,
1172 and it now reports if a shared library has no debugging information.
1174 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1175 now complete on file names.
1177 * When completing in expressions, gdb will attempt to limit
1178 completions to allowable structure or union fields, where appropriate.
1179 For instance, consider:
1181 # struct example { int f1; double f2; };
1182 # struct example variable;
1185 If the user types TAB at the end of this command line, the available
1186 completions will be "f1" and "f2".
1188 * Inlined functions are now supported. They show up in backtraces, and
1189 the "step", "next", and "finish" commands handle them automatically.
1191 * GDB now supports the token-splicing (##) and stringification (#)
1192 operators when expanding macros. It also supports variable-arity
1195 * GDB now supports inspecting extra signal information, exported by
1196 the new $_siginfo convenience variable. The feature is currently
1197 implemented on linux ARM, i386 and amd64.
1199 * GDB can now display the VFP floating point registers and NEON vector
1200 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1201 can provide these registers (requires Linux 2.6.30 or later). Remote
1202 and simulator targets may also provide them.
1204 * New remote packets
1207 Search memory for a sequence of bytes.
1210 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1211 operation over reliable transport links. Use of this packet is
1212 controlled by the `set remote noack-packet' command.
1215 Kill the process with the specified process ID. Use this in preference
1216 to `k' when multiprocess protocol extensions are supported.
1219 Obtains additional operating system information
1223 Read or write additional signal information.
1225 * Removed remote protocol undocumented extension
1227 An undocumented extension to the remote protocol's `S' stop reply
1228 packet that permited the stub to pass a process id was removed.
1229 Remote servers should use the `T' stop reply packet instead.
1231 * GDB now supports multiple function calling conventions according to the
1232 DWARF-2 DW_AT_calling_convention function attribute.
1234 * The SH target utilizes the aforementioned change to distinguish between gcc
1235 and Renesas calling convention. It also adds the new CLI commands
1236 `set/show sh calling-convention'.
1238 * GDB can now read compressed debug sections, as produced by GNU gold
1239 with the --compress-debug-sections=zlib flag.
1241 * 64-bit core files are now supported on AIX.
1243 * Thread switching is now supported on Tru64.
1245 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1246 which will be allocated using malloc later in program execution.
1248 * The qXfer:libraries:read remote procotol packet now allows passing a
1249 list of section offsets.
1251 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1252 conditions handling signals delivered during attach or thread creation
1253 have also been fixed.
1255 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1256 From the user's standpoint, all unqualified instances of True and False
1257 are treated as the standard definitions, regardless of context.
1259 * GDB now parses C++ symbol and type names more flexibly. For
1262 template<typename T> class C { };
1265 GDB will now correctly handle all of:
1267 ptype C<char const *>
1268 ptype C<char const*>
1269 ptype C<const char *>
1270 ptype C<const char*>
1272 * New features in the GDB remote stub, gdbserver
1274 - The "--wrapper" command-line argument tells gdbserver to use a
1275 wrapper program to launch programs for debugging.
1277 - On PowerPC and S/390 targets, it is now possible to use a single
1278 gdbserver executable to debug both 32-bit and 64-bit programs.
1279 (This requires gdbserver itself to be built as a 64-bit executable.)
1281 - gdbserver uses the new noack protocol mode for TCP connections to
1282 reduce communications latency, if also supported and enabled in GDB.
1284 - Support for the sparc64-linux-gnu target is now included in
1287 - The amd64-linux build of gdbserver now supports debugging both
1288 32-bit and 64-bit programs.
1290 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1291 now support hardware watchpoints, and will use them automatically
1296 GDB now has support for scripting using Python. Whether this is
1297 available is determined at configure time.
1299 New GDB commands can now be written in Python.
1301 * Ada tasking support
1303 Ada tasks can now be inspected in GDB. The following commands have
1307 Print the list of Ada tasks.
1309 Print detailed information about task number N.
1311 Print the task number of the current task.
1313 Switch the context of debugging to task number N.
1315 * Support for user-defined prefixed commands. The "define" command can
1316 add new commands to existing prefixes, e.g. "target".
1318 * Multi-inferior, multi-process debugging.
1320 GDB now has generalized support for multi-inferior debugging. See
1321 "Debugging Multiple Inferiors" in the manual for more information.
1322 Although availability still depends on target support, the command
1323 set is more uniform now. The GNU/Linux specific multi-forks support
1324 has been migrated to this new framework. This implied some user
1325 visible changes; see "New commands" and also "Removed commands"
1328 * Target descriptions can now describe the target OS ABI. See the
1329 "Target Description Format" section in the user manual for more
1332 * Target descriptions can now describe "compatible" architectures
1333 to indicate that the target can execute applications for a different
1334 architecture in addition to those for the main target architecture.
1335 See the "Target Description Format" section in the user manual for
1338 * Multi-architecture debugging.
1340 GDB now includes general supports for debugging applications on
1341 hybrid systems that use more than one single processor architecture
1342 at the same time. Each such hybrid architecture still requires
1343 specific support to be added. The only hybrid architecture supported
1344 in this version of GDB is the Cell Broadband Engine.
1346 * GDB now supports integrated debugging of Cell/B.E. applications that
1347 use both the PPU and SPU architectures. To enable support for hybrid
1348 Cell/B.E. debugging, you need to configure GDB to support both the
1349 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1350 --enable-targets configure option.
1352 * Non-stop mode debugging.
1354 For some targets, GDB now supports an optional mode of operation in
1355 which you can examine stopped threads while other threads continue
1356 to execute freely. This is referred to as non-stop mode, with the
1357 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1358 section in the user manual for more information.
1360 To be able to support remote non-stop debugging, a remote stub needs
1361 to implement the non-stop mode remote protocol extensions, as
1362 described in the "Remote Non-Stop" section of the user manual. The
1363 GDB remote stub, gdbserver, has been adjusted to support these
1364 extensions on linux targets.
1366 * New commands (for set/show, see "New options" below)
1368 catch syscall [NAME(S) | NUMBER(S)]
1369 Catch system calls. Arguments, which should be names of system
1370 calls or their numbers, mean catch only those syscalls. Without
1371 arguments, every syscall will be caught. When the inferior issues
1372 any of the specified syscalls, GDB will stop and announce the system
1373 call, both when it is called and when its call returns. This
1374 feature is currently available with a native GDB running on the
1375 Linux Kernel, under the following architectures: x86, x86_64,
1376 PowerPC and PowerPC64.
1378 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1380 Search memory for a sequence of bytes.
1382 maint set python print-stack
1383 maint show python print-stack
1384 Show a stack trace when an error is encountered in a Python script.
1387 Invoke CODE by passing it to the Python interpreter.
1392 These allow macros to be defined, undefined, and listed
1396 Show operating system information about processes.
1399 List the inferiors currently under GDB's control.
1402 Switch focus to inferior number NUM.
1405 Detach from inferior number NUM.
1408 Kill inferior number NUM.
1412 set spu stop-on-load
1413 show spu stop-on-load
1414 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1416 set spu auto-flush-cache
1417 show spu auto-flush-cache
1418 Control whether to automatically flush the software-managed cache
1419 during Cell/B.E. debugging.
1421 set sh calling-convention
1422 show sh calling-convention
1423 Control the calling convention used when calling SH target functions.
1426 show debug timestamp
1427 Control display of timestamps with GDB debugging output.
1429 set disassemble-next-line
1430 show disassemble-next-line
1431 Control display of disassembled source lines or instructions when
1434 set remote noack-packet
1435 show remote noack-packet
1436 Set/show the use of remote protocol QStartNoAckMode packet. See above
1437 under "New remote packets."
1439 set remote query-attached-packet
1440 show remote query-attached-packet
1441 Control use of remote protocol `qAttached' (query-attached) packet.
1443 set remote read-siginfo-object
1444 show remote read-siginfo-object
1445 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1448 set remote write-siginfo-object
1449 show remote write-siginfo-object
1450 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1453 set remote reverse-continue
1454 show remote reverse-continue
1455 Control use of remote protocol 'bc' (reverse-continue) packet.
1457 set remote reverse-step
1458 show remote reverse-step
1459 Control use of remote protocol 'bs' (reverse-step) packet.
1461 set displaced-stepping
1462 show displaced-stepping
1463 Control displaced stepping mode. Displaced stepping is a way to
1464 single-step over breakpoints without removing them from the debuggee.
1465 Also known as "out-of-line single-stepping".
1468 show debug displaced
1469 Control display of debugging info for displaced stepping.
1471 maint set internal-error
1472 maint show internal-error
1473 Control what GDB does when an internal error is detected.
1475 maint set internal-warning
1476 maint show internal-warning
1477 Control what GDB does when an internal warning is detected.
1482 Use a wrapper program to launch programs for debugging.
1484 set multiple-symbols (all|ask|cancel)
1485 show multiple-symbols
1486 The value of this variable can be changed to adjust the debugger behavior
1487 when an expression or a breakpoint location contains an ambiguous symbol
1488 name (an overloaded function name, for instance).
1490 set breakpoint always-inserted
1491 show breakpoint always-inserted
1492 Keep breakpoints always inserted in the target, as opposed to inserting
1493 them when resuming the target, and removing them when the target stops.
1494 This option can improve debugger performance on slow remote targets.
1496 set arm fallback-mode (arm|thumb|auto)
1497 show arm fallback-mode
1498 set arm force-mode (arm|thumb|auto)
1500 These commands control how ARM GDB determines whether instructions
1501 are ARM or Thumb. The default for both settings is auto, which uses
1502 the current CPSR value for instructions without symbols; previous
1503 versions of GDB behaved as if "set arm fallback-mode arm".
1505 set disable-randomization
1506 show disable-randomization
1507 Standalone programs run with the virtual address space randomization enabled
1508 by default on some platforms. This option keeps the addresses stable across
1509 multiple debugging sessions.
1513 Control whether other threads are stopped or not when some thread hits
1518 Requests that asynchronous execution is enabled in the target, if available.
1519 In this case, it's possible to resume target in the background, and interact
1520 with GDB while the target is running. "show target-async" displays the
1521 current state of asynchronous execution of the target.
1523 set target-wide-charset
1524 show target-wide-charset
1525 The target-wide-charset is the name of the character set that GDB
1526 uses when printing characters whose type is wchar_t.
1528 set tcp auto-retry (on|off)
1530 set tcp connect-timeout
1531 show tcp connect-timeout
1532 These commands allow GDB to retry failed TCP connections to a remote stub
1533 with a specified timeout period; this is useful if the stub is launched
1534 in parallel with GDB but may not be ready to accept connections immediately.
1536 set libthread-db-search-path
1537 show libthread-db-search-path
1538 Control list of directories which GDB will search for appropriate
1541 set schedule-multiple (on|off)
1542 show schedule-multiple
1543 Allow GDB to resume all threads of all processes or only threads of
1544 the current process.
1548 Use more aggressive caching for accesses to the stack. This improves
1549 performance of remote debugging (particularly backtraces) without
1550 affecting correctness.
1552 set interactive-mode (on|off|auto)
1553 show interactive-mode
1554 Control whether GDB runs in interactive mode (on) or not (off).
1555 When in interactive mode, GDB waits for the user to answer all
1556 queries. Otherwise, GDB does not wait and assumes the default
1557 answer. When set to auto (the default), GDB determines which
1558 mode to use based on the stdin settings.
1563 For program forks, this is replaced by the new more generic `info
1564 inferiors' command. To list checkpoints, you can still use the
1565 `info checkpoints' command, which was an alias for the `info forks'
1569 Replaced by the new `inferior' command. To switch between
1570 checkpoints, you can still use the `restart' command, which was an
1571 alias for the `fork' command.
1574 This is removed, since some targets don't have a notion of
1575 processes. To switch between processes, you can still use the
1576 `inferior' command using GDB's own inferior number.
1579 For program forks, this is replaced by the new more generic `kill
1580 inferior' command. To delete a checkpoint, you can still use the
1581 `delete checkpoint' command, which was an alias for the `delete
1585 For program forks, this is replaced by the new more generic `detach
1586 inferior' command. To detach a checkpoint, you can still use the
1587 `detach checkpoint' command, which was an alias for the `detach
1590 * New native configurations
1592 x86/x86_64 Darwin i[34567]86-*-darwin*
1594 x86_64 MinGW x86_64-*-mingw*
1598 Lattice Mico32 lm32-*
1599 x86 DICOS i[34567]86-*-dicos*
1600 x86_64 DICOS x86_64-*-dicos*
1603 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1604 (mingw32ce) debugging.
1610 These commands were actually not implemented on any target.
1612 *** Changes in GDB 6.8
1614 * New native configurations
1616 NetBSD/hppa hppa*-*netbsd*
1617 Xtensa GNU/Linux xtensa*-*-linux*
1621 NetBSD/hppa hppa*-*-netbsd*
1622 Xtensa GNU/Lunux xtensa*-*-linux*
1624 * Change in command line behavior -- corefiles vs. process ids.
1626 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1627 attaching to process NUMBER fails, GDB no longer attempts to open a
1628 core file named NUMBER. Attaching to a program using the -c option
1629 is no longer supported. Instead, use the '-p' or '--pid' options.
1631 * GDB can now be built as a native debugger for debugging Windows x86
1632 (mingw32) Portable Executable (PE) programs.
1634 * Pending breakpoints no longer change their number when their address
1637 * GDB now supports breakpoints with multiple locations,
1638 including breakpoints on C++ constructors, inside C++ templates,
1639 and in inlined functions.
1641 * GDB's ability to debug optimized code has been improved. GDB more
1642 accurately identifies function bodies and lexical blocks that occupy
1643 more than one contiguous range of addresses.
1645 * Target descriptions can now describe registers for PowerPC.
1647 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1648 registers on PowerPC targets.
1650 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1651 targets even when the libthread_db library is not available.
1653 * The GDB remote stub, gdbserver, now supports the new file transfer
1654 commands (remote put, remote get, and remote delete).
1656 * The GDB remote stub, gdbserver, now supports run and attach in
1657 extended-remote mode.
1659 * hppa*64*-*-hpux11* target broken
1660 The debugger is unable to start a program and fails with the following
1661 error: "Error trying to get information about dynamic linker".
1662 The gdb-6.7 release is also affected.
1664 * GDB now supports the --enable-targets= configure option to allow
1665 building a single GDB executable that supports multiple remote
1666 target architectures.
1668 * GDB now supports debugging C and C++ programs which use the
1669 Decimal Floating Point extension. In addition, the PowerPC target
1670 now has a set of pseudo-registers to inspect decimal float values
1671 stored in two consecutive float registers.
1673 * The -break-insert MI command can optionally create pending
1676 * Improved support for debugging Ada
1677 Many improvements to the Ada language support have been made. These
1679 - Better support for Ada2005 interface types
1680 - Improved handling of arrays and slices in general
1681 - Better support for Taft-amendment types
1682 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1684 - Improved command completion in Ada
1687 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1692 set print frame-arguments (all|scalars|none)
1693 show print frame-arguments
1694 The value of this variable can be changed to control which argument
1695 values should be printed by the debugger when displaying a frame.
1700 Transfer files to and from a remote target, and delete remote files.
1707 Transfer files to and from a remote target, and delete remote files.
1709 * New remote packets
1716 Open, close, read, write, and delete files on the remote system.
1719 Attach to an existing process on the remote system, in extended-remote
1723 Run a new process on the remote system, in extended-remote mode.
1725 *** Changes in GDB 6.7
1727 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1728 bfd, libiberty and opcodes, as revealed by static analysis donated by
1729 Coverity, Inc. (http://scan.coverity.com).
1731 * When looking up multiply-defined global symbols, GDB will now prefer the
1732 symbol definition in the current shared library if it was built using the
1733 -Bsymbolic linker option.
1735 * When the Text User Interface (TUI) is not configured, GDB will now
1736 recognize the -tui command-line option and print a message that the TUI
1739 * The GDB remote stub, gdbserver, now has lower overhead for high
1740 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1742 * GDB for MIPS targets now autodetects whether a remote target provides
1743 32-bit or 64-bit register values.
1745 * Support for C++ member pointers has been improved.
1747 * GDB now understands XML target descriptions, which specify the
1748 target's overall architecture. GDB can read a description from
1749 a local file or over the remote serial protocol.
1751 * Vectors of single-byte data use a new integer type which is not
1752 automatically displayed as character or string data.
1754 * The /s format now works with the print command. It displays
1755 arrays of single-byte integers and pointers to single-byte integers
1758 * Target descriptions can now describe target-specific registers,
1759 for architectures which have implemented the support (currently
1760 only ARM, M68K, and MIPS).
1762 * GDB and the GDB remote stub, gdbserver, now support the XScale
1765 * The GDB remote stub, gdbserver, has been updated to support
1766 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1767 has been rewritten to use the standard GDB remote protocol.
1769 * GDB can now step into C++ functions which are called through thunks.
1771 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1773 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1774 layout. It also supports a TextSeg= and DataSeg= response when only
1775 segment base addresses (rather than offsets) are available.
1777 * The /i format now outputs any trailing branch delay slot instructions
1778 immediately following the last instruction within the count specified.
1780 * The GDB remote protocol "T" stop reply packet now supports a
1781 "library" response. Combined with the new "qXfer:libraries:read"
1782 packet, this response allows GDB to debug shared libraries on targets
1783 where the operating system manages the list of loaded libraries (e.g.
1784 Windows and SymbianOS).
1786 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1787 (DLLs) on Windows and Windows CE targets.
1789 * GDB now supports a faster verification that a .debug file matches its binary
1790 according to its build-id signature, if the signature is present.
1796 Enable or disable hardware flow control (RTS/CTS) on the serial port
1797 when debugging using remote targets.
1799 set mem inaccessible-by-default
1800 show mem inaccessible-by-default
1801 If the target supplies a memory map, for instance via the remote
1802 protocol's "qXfer:memory-map:read" packet, setting this variable
1803 prevents GDB from accessing memory outside the memory map. This
1804 is useful for targets with memory mapped registers or which react
1805 badly to accesses of unmapped address space.
1807 set breakpoint auto-hw
1808 show breakpoint auto-hw
1809 If the target supplies a memory map, for instance via the remote
1810 protocol's "qXfer:memory-map:read" packet, setting this variable
1811 lets GDB use hardware breakpoints automatically for memory regions
1812 where it can not use software breakpoints. This covers both the
1813 "break" command and internal breakpoints used for other commands
1814 including "next" and "finish".
1817 catch exception unhandled
1818 Stop the program execution when Ada exceptions are raised.
1821 Stop the program execution when an Ada assertion failed.
1825 Set an alternate system root for target files. This is a more
1826 general version of "set solib-absolute-prefix", which is now
1827 an alias to "set sysroot".
1830 Provide extended SPU facility status information. This set of
1831 commands is available only when debugging the Cell/B.E. SPU
1834 * New native configurations
1836 OpenBSD/sh sh*-*openbsd*
1839 unset tdesc filename
1841 Use the specified local file as an XML target description, and do
1842 not query the target for its built-in description.
1846 OpenBSD/sh sh*-*-openbsd*
1847 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1848 Toshiba Media Processor mep-elf
1850 * New remote packets
1853 Ignore the specified signals; pass them directly to the debugged program
1854 without stopping other threads or reporting them to GDB.
1856 qXfer:features:read:
1857 Read an XML target description from the target, which describes its
1862 Read or write contents of an spufs file on the target system. These
1863 packets are available only on the Cell/B.E. SPU architecture.
1865 qXfer:libraries:read:
1866 Report the loaded shared libraries. Combined with new "T" packet
1867 response, this packet allows GDB to debug shared libraries on
1868 targets where the operating system manages the list of loaded
1869 libraries (e.g. Windows and SymbianOS).
1873 Support for these obsolete configurations has been removed.
1881 i[34567]86-*-lynxos*
1882 i[34567]86-*-netware*
1883 i[34567]86-*-sco3.2v5*
1884 i[34567]86-*-sco3.2v4*
1886 i[34567]86-*-sysv4.2*
1889 i[34567]86-*-unixware2*
1890 i[34567]86-*-unixware*
1899 * Other removed features
1906 Various m68k-only ROM monitors.
1913 Various Renesas ROM monitors and debugging interfaces for SH and
1918 Support for a Macraigor serial interface to on-chip debugging.
1919 GDB does not directly support the newer parallel or USB
1924 A debug information format. The predecessor to DWARF 2 and
1925 DWARF 3, which are still supported.
1927 Support for the HP aCC compiler on HP-UX/PA-RISC
1929 SOM-encapsulated symbolic debugging information, automatic
1930 invocation of pxdb, and the aCC custom C++ ABI. This does not
1931 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1932 with aCC can still be debugged on an assembly level.
1934 MIPS ".pdr" sections
1936 A MIPS-specific format used to describe stack frame layout
1937 in debugging information.
1941 GDB could work with an older version of Guile to debug
1942 the interpreter and Scheme programs running in it.
1944 set mips stack-arg-size
1945 set mips saved-gpreg-size
1947 Use "set mips abi" to control parameter passing for MIPS.
1949 *** Changes in GDB 6.6
1954 Cell Broadband Engine SPU spu-elf
1956 * GDB can now be configured as a cross-debugger targeting native Windows
1957 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1958 running on a Windows system over TCP/IP to debug Windows programs.
1960 * The GDB remote stub, gdbserver, has been updated to support Windows and
1961 Cygwin debugging. Both single-threaded and multi-threaded programs are
1964 * The "set trust-readonly-sections" command works again. This command was
1965 broken in GDB 6.3, 6.4, and 6.5.
1967 * The "load" command now supports writing to flash memory, if the remote
1968 stub provides the required support.
1970 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1971 longer requires symbolic debug information (e.g. DWARF-2).
1976 unset substitute-path
1977 show substitute-path
1978 Manage a list of substitution rules that GDB uses to rewrite the name
1979 of the directories where the sources are located. This can be useful
1980 for instance when the sources were moved to a different location
1981 between compilation and debugging.
1985 Print each CLI command as it is executed. Each command is prefixed with
1986 a number of `+' symbols representing the nesting depth.
1987 The source command now has a `-v' option to enable the same feature.
1991 The ARM Demon monitor support (RDP protocol, "target rdp").
1993 Kernel Object Display, an embedded debugging feature which only worked with
1994 an obsolete version of Cisco IOS.
1996 The 'set download-write-size' and 'show download-write-size' commands.
1998 * New remote packets
2001 Tell a stub about GDB client features, and request remote target features.
2002 The first feature implemented is PacketSize, which allows the target to
2003 specify the size of packets it can handle - to minimize the number of
2004 packets required and improve performance when connected to a remote
2008 Fetch an OS auxilliary vector from the remote stub. This packet is a
2009 more efficient replacement for qPart:auxv:read.
2011 qXfer:memory-map:read:
2012 Fetch a memory map from the remote stub, including information about
2013 RAM, ROM, and flash memory devices.
2018 Erase and program a flash memory device.
2020 * Removed remote packets
2023 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2024 used it, and only gdbserver implemented it.
2026 *** Changes in GDB 6.5
2030 Renesas M32C/M16C m32c-elf
2032 Morpho Technologies ms1 ms1-elf
2036 init-if-undefined Initialize a convenience variable, but
2037 only if it doesn't already have a value.
2039 The following commands are presently only implemented for native GNU/Linux:
2041 checkpoint Save a snapshot of the program state.
2043 restart <n> Return the program state to a
2044 previously saved state.
2046 info checkpoints List currently saved checkpoints.
2048 delete-checkpoint <n> Delete a previously saved checkpoint.
2050 set|show detach-on-fork Tell gdb whether to detach from a newly
2051 forked process, or to keep debugging it.
2053 info forks List forks of the user program that
2054 are available to be debugged.
2056 fork <n> Switch to debugging one of several
2057 forks of the user program that are
2058 available to be debugged.
2060 delete-fork <n> Delete a fork from the list of forks
2061 that are available to be debugged (and
2062 kill the forked process).
2064 detach-fork <n> Delete a fork from the list of forks
2065 that are available to be debugged (and
2066 allow the process to continue).
2070 Morpho Technologies ms2 ms1-elf
2072 * Improved Windows host support
2074 GDB now builds as a cross debugger hosted on i686-mingw32, including
2075 native console support, and remote communications using either
2076 network sockets or serial ports.
2078 * Improved Modula-2 language support
2080 GDB can now print most types in the Modula-2 syntax. This includes:
2081 basic types, set types, record types, enumerated types, range types,
2082 pointer types and ARRAY types. Procedure var parameters are correctly
2083 printed and hexadecimal addresses and character constants are also
2084 written in the Modula-2 syntax. Best results can be obtained by using
2085 GNU Modula-2 together with the -gdwarf-2 command line option.
2089 The ARM rdi-share module.
2091 The Netware NLM debug server.
2093 *** Changes in GDB 6.4
2095 * New native configurations
2097 OpenBSD/arm arm*-*-openbsd*
2098 OpenBSD/mips64 mips64-*-openbsd*
2102 Morpho Technologies ms1 ms1-elf
2104 * New command line options
2106 --batch-silent As for --batch, but totally silent.
2107 --return-child-result The debugger will exist with the same value
2108 the child (debugged) program exited with.
2109 --eval-command COMMAND, -ex COMMAND
2110 Execute a single GDB CLI command. This may be
2111 specified multiple times and in conjunction
2112 with the --command (-x) option.
2114 * Deprecated commands removed
2116 The following commands, that were deprecated in 2000, have been
2120 set|show arm disassembly-flavor set|show arm disassembler
2121 othernames set arm disassembler
2122 set|show remotedebug set|show debug remote
2123 set|show archdebug set|show debug arch
2124 set|show eventdebug set|show debug event
2127 * New BSD user-level threads support
2129 It is now possible to debug programs using the user-level threads
2130 library on OpenBSD and FreeBSD. Currently supported (target)
2133 FreeBSD/amd64 x86_64-*-freebsd*
2134 FreeBSD/i386 i386-*-freebsd*
2135 OpenBSD/i386 i386-*-openbsd*
2137 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2138 are not yet supported.
2140 * New support for Matsushita MN10300 w/sim added
2141 (Work in progress). mn10300-elf.
2143 * REMOVED configurations and files
2145 VxWorks and the XDR protocol *-*-vxworks
2146 Motorola MCORE mcore-*-*
2147 National Semiconductor NS32000 ns32k-*-*
2149 * New "set print array-indexes" command
2151 After turning this setting "on", GDB prints the index of each element
2152 when displaying arrays. The default is "off" to preserve the previous
2155 * VAX floating point support
2157 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2159 * User-defined command support
2161 In addition to using $arg0..$arg9 for argument passing, it is now possible
2162 to use $argc to determine now many arguments have been passed. See the
2163 section on user-defined commands in the user manual for more information.
2165 *** Changes in GDB 6.3:
2167 * New command line option
2169 GDB now accepts -l followed by a number to set the timeout for remote
2172 * GDB works with GCC -feliminate-dwarf2-dups
2174 GDB now supports a more compact representation of DWARF-2 debug
2175 information using DW_FORM_ref_addr references. These are produced
2176 by GCC with the option -feliminate-dwarf2-dups and also by some
2177 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2178 to use -feliminate-dwarf2-dups.
2180 * Internationalization
2182 When supported by the host system, GDB will be built with
2183 internationalization (libintl). The task of marking up the sources is
2184 continued, we're looking forward to our first translation.
2188 Initial support for debugging programs compiled with the GNAT
2189 implementation of the Ada programming language has been integrated
2190 into GDB. In this release, support is limited to expression evaluation.
2192 * New native configurations
2194 GNU/Linux/m32r m32r-*-linux-gnu
2198 GDB's remote protocol now includes support for the 'p' packet. This
2199 packet is used to fetch individual registers from a remote inferior.
2201 * END-OF-LIFE registers[] compatibility module
2203 GDB's internal register infrastructure has been completely rewritten.
2204 The new infrastructure making possible the implementation of key new
2205 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2208 GDB 6.3 will be the last release to include the the registers[]
2209 compatibility module that allowed out-of-date configurations to
2210 continue to work. This change directly impacts the following
2220 powerpc bdm protocol
2222 Unless there is activity to revive these configurations, they will be
2223 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2225 * OBSOLETE configurations and files
2227 Configurations that have been declared obsolete in this release have
2228 been commented out. Unless there is activity to revive these
2229 configurations, the next release of GDB will have their sources
2230 permanently REMOVED.
2239 *** Changes in GDB 6.2.1:
2241 * MIPS `break main; run' gave an heuristic-fence-post warning
2243 When attempting to run even a simple program, a warning about
2244 heuristic-fence-post being hit would be reported. This problem has
2247 * MIPS IRIX 'long double' crashed GDB
2249 When examining a long double variable, GDB would get a segmentation
2250 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2251 IRIX long double values).
2255 A bug in the VAX stack code was causing problems with the "next"
2256 command. This problem has been fixed.
2258 *** Changes in GDB 6.2:
2260 * Fix for ``many threads''
2262 On GNU/Linux systems that use the NPTL threads library, a program
2263 rapidly creating and deleting threads would confuse GDB leading to the
2266 ptrace: No such process.
2267 thread_db_get_info: cannot get thread info: generic error
2269 This problem has been fixed.
2271 * "-async" and "-noasync" options removed.
2273 Support for the broken "-noasync" option has been removed (it caused
2276 * New ``start'' command.
2278 This command runs the program until the begining of the main procedure.
2280 * New BSD Kernel Data Access Library (libkvm) interface
2282 Using ``target kvm'' it is now possible to debug kernel core dumps and
2283 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2284 platforms. Currently supported (native-only) configurations are:
2286 FreeBSD/amd64 x86_64-*-freebsd*
2287 FreeBSD/i386 i?86-*-freebsd*
2288 NetBSD/i386 i?86-*-netbsd*
2289 NetBSD/m68k m68*-*-netbsd*
2290 NetBSD/sparc sparc-*-netbsd*
2291 OpenBSD/amd64 x86_64-*-openbsd*
2292 OpenBSD/i386 i?86-*-openbsd*
2293 OpenBSD/m68k m68*-openbsd*
2294 OpenBSD/sparc sparc-*-openbsd*
2296 * Signal trampoline code overhauled
2298 Many generic problems with GDB's signal handling code have been fixed.
2299 These include: backtraces through non-contiguous stacks; recognition
2300 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2301 call; backtrace through a signal trampoline; step into and out of
2302 signal handlers; and single-stepping in the signal trampoline.
2304 Please note that kernel bugs are a limiting factor here. These
2305 features have been shown to work on an s390 GNU/Linux system that
2306 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2308 * Cygwin support for DWARF 2 added.
2310 * New native configurations
2312 GNU/Linux/hppa hppa*-*-linux*
2313 OpenBSD/hppa hppa*-*-openbsd*
2314 OpenBSD/m68k m68*-*-openbsd*
2315 OpenBSD/m88k m88*-*-openbsd*
2316 OpenBSD/powerpc powerpc-*-openbsd*
2317 NetBSD/vax vax-*-netbsd*
2318 OpenBSD/vax vax-*-openbsd*
2320 * END-OF-LIFE frame compatibility module
2322 GDB's internal frame infrastructure has been completely rewritten.
2323 The new infrastructure making it possible to support key new features
2324 including DWARF 2 Call Frame Information. To aid in the task of
2325 migrating old configurations to this new infrastructure, a
2326 compatibility module, that allowed old configurations to continue to
2327 work, was also included.
2329 GDB 6.2 will be the last release to include this frame compatibility
2330 module. This change directly impacts the following configurations:
2340 Unless there is activity to revive these configurations, they will be
2341 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2343 * REMOVED configurations and files
2345 Sun 3, running SunOS 3 m68*-*-sunos3*
2346 Sun 3, running SunOS 4 m68*-*-sunos4*
2347 Sun 2, running SunOS 3 m68000-*-sunos3*
2348 Sun 2, running SunOS 4 m68000-*-sunos4*
2349 Motorola 680x0 running LynxOS m68*-*-lynxos*
2350 AT&T 3b1/Unix pc m68*-att-*
2351 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2352 decstation mips-dec-* mips-little-*
2353 riscos mips-*-riscos* mips-*-sysv*
2354 sonymips mips-sony-*
2355 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2357 *** Changes in GDB 6.1.1:
2359 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2361 The TUI (Text-mode User Interface) is now built as part of a default
2362 GDB configuration. It is enabled by either selecting the TUI with the
2363 command line option "-i=tui" or by running the separate "gdbtui"
2364 program. For more information on the TUI, see the manual "Debugging
2367 * Pending breakpoint support (also included in GDB 6.1)
2369 Support has been added to allow you to specify breakpoints in shared
2370 libraries that have not yet been loaded. If a breakpoint location
2371 cannot be found, and the "breakpoint pending" option is set to auto,
2372 GDB queries you if you wish to make the breakpoint pending on a future
2373 shared-library load. If and when GDB resolves the breakpoint symbol,
2374 the pending breakpoint is removed as one or more regular breakpoints
2377 Pending breakpoints are very useful for GCJ Java debugging.
2379 * Fixed ISO-C build problems
2381 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2382 non ISO-C code that stopped them being built using a more strict ISO-C
2383 compiler (e.g., IBM's C compiler).
2385 * Fixed build problem on IRIX 5
2387 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2388 wasn't able to compile compile on an IRIX 5 system.
2390 * Added execute permission to gdb/gdbserver/configure
2392 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2393 permission. This bug would cause configure to fail on a number of
2394 systems (Solaris, IRIX). Ref: server/519.
2396 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2398 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2399 has been updated to use constant array sizes.
2401 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2403 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2404 its generated DWARF Call Frame Info. This encoding was causing GDB to
2405 panic, that panic has been fixed. Ref: gdb/1628.
2407 * Fixed a problem when examining parameters in shared library code.
2409 When examining parameters in optimized shared library code generated
2410 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2411 not available''. GDB now correctly displays the variable's value.
2413 *** Changes in GDB 6.1:
2415 * Removed --with-mmalloc
2417 Support for the mmalloc memory manager has been removed, as it
2418 conflicted with the internal gdb byte cache.
2420 * Changes in AMD64 configurations
2422 The AMD64 target now includes the %cs and %ss registers. As a result
2423 the AMD64 remote protocol has changed; this affects the floating-point
2424 and SSE registers. If you rely on those registers for your debugging,
2425 you should upgrade gdbserver on the remote side.
2427 * Revised SPARC target
2429 The SPARC target has been completely revised, incorporating the
2430 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2431 support for LynxOS and SunOS 4 has been dropped. Calling functions
2432 from within GDB on operating systems with a non-executable stack
2433 (Solaris, OpenBSD) now works.
2437 GDB has a new C++ demangler which does a better job on the mangled
2438 names generated by current versions of g++. It also runs faster, so
2439 with this and other changes gdb should now start faster on large C++
2442 * DWARF 2 Location Expressions
2444 GDB support for location expressions has been extended to support function
2445 arguments and frame bases. Older versions of GDB could crash when they
2448 * C++ nested types and namespaces
2450 GDB's support for nested types and namespaces in C++ has been
2451 improved, especially if you use the DWARF 2 debugging format. (This
2452 is the default for recent versions of GCC on most platforms.)
2453 Specifically, if you have a class "Inner" defined within a class or
2454 namespace "Outer", then GDB realizes that the class's name is
2455 "Outer::Inner", not simply "Inner". This should greatly reduce the
2456 frequency of complaints about not finding RTTI symbols. In addition,
2457 if you are stopped at inside of a function defined within a namespace,
2458 GDB modifies its name lookup accordingly.
2460 * New native configurations
2462 NetBSD/amd64 x86_64-*-netbsd*
2463 OpenBSD/amd64 x86_64-*-openbsd*
2464 OpenBSD/alpha alpha*-*-openbsd*
2465 OpenBSD/sparc sparc-*-openbsd*
2466 OpenBSD/sparc64 sparc64-*-openbsd*
2468 * New debugging protocols
2470 M32R with SDI protocol m32r-*-elf*
2472 * "set prompt-escape-char" command deleted.
2474 The command "set prompt-escape-char" has been deleted. This command,
2475 and its very obscure effet on GDB's prompt, was never documented,
2476 tested, nor mentioned in the NEWS file.
2478 * OBSOLETE configurations and files
2480 Configurations that have been declared obsolete in this release have
2481 been commented out. Unless there is activity to revive these
2482 configurations, the next release of GDB will have their sources
2483 permanently REMOVED.
2485 Sun 3, running SunOS 3 m68*-*-sunos3*
2486 Sun 3, running SunOS 4 m68*-*-sunos4*
2487 Sun 2, running SunOS 3 m68000-*-sunos3*
2488 Sun 2, running SunOS 4 m68000-*-sunos4*
2489 Motorola 680x0 running LynxOS m68*-*-lynxos*
2490 AT&T 3b1/Unix pc m68*-att-*
2491 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2492 decstation mips-dec-* mips-little-*
2493 riscos mips-*-riscos* mips-*-sysv*
2494 sonymips mips-sony-*
2495 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2497 * REMOVED configurations and files
2499 SGI Irix-4.x mips-sgi-irix4 or iris4
2500 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2501 Z8000 simulator z8k-zilog-none or z8ksim
2502 Matsushita MN10200 w/simulator mn10200-*-*
2503 H8/500 simulator h8500-hitachi-hms or h8500hms
2504 HP/PA running BSD hppa*-*-bsd*
2505 HP/PA running OSF/1 hppa*-*-osf*
2506 HP/PA Pro target hppa*-*-pro*
2507 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2508 386BSD i[3456]86-*-bsd*
2509 Sequent family i[3456]86-sequent-sysv4*
2510 i[3456]86-sequent-sysv*
2511 i[3456]86-sequent-bsd*
2512 SPARC running LynxOS sparc-*-lynxos*
2513 SPARC running SunOS 4 sparc-*-sunos4*
2514 Tsqware Sparclet sparclet-*-*
2515 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2517 *** Changes in GDB 6.0:
2521 Support for debugging the Objective-C programming language has been
2522 integrated into GDB.
2524 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2526 DWARF 2's Call Frame Information makes available compiler generated
2527 information that more exactly describes the program's run-time stack.
2528 By using this information, GDB is able to provide more robust stack
2531 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2532 have been updated to use a new backtrace mechanism which includes
2533 DWARF 2 CFI support.
2537 GDB's remote protocol has been extended to include support for hosted
2538 file I/O (where the remote target uses GDB's file system). See GDB's
2539 remote protocol documentation for details.
2541 * All targets using the new architecture framework.
2543 All of GDB's targets have been updated to use the new internal
2544 architecture framework. The way is now open for future GDB releases
2545 to include cross-architecture native debugging support (i386 on amd64,
2548 * GNU/Linux's Thread Local Storage (TLS)
2550 GDB now includes support for for the GNU/Linux implementation of
2551 per-thread variables.
2553 * GNU/Linux's Native POSIX Thread Library (NPTL)
2555 GDB's thread code has been updated to work with either the new
2556 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2558 * Separate debug info.
2560 GDB, in conjunction with BINUTILS, now supports a mechanism for
2561 automatically loading debug information from a separate file. Instead
2562 of shipping full debug and non-debug versions of system libraries,
2563 system integrators can now instead ship just the stripped libraries
2564 and optional debug files.
2566 * DWARF 2 Location Expressions
2568 DWARF 2 Location Expressions allow the compiler to more completely
2569 describe the location of variables (even in optimized code) to the
2572 GDB now includes preliminary support for location expressions (support
2573 for DW_OP_piece is still missing).
2577 A number of long standing bugs that caused GDB to die while starting a
2578 Java application have been fixed. GDB's Java support is now
2579 considered "useable".
2581 * GNU/Linux support for fork, vfork, and exec.
2583 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2584 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2587 * GDB supports logging output to a file
2589 There are two new commands, "set logging" and "show logging", which can be
2590 used to capture GDB's output to a file.
2592 * The meaning of "detach" has changed for gdbserver
2594 The "detach" command will now resume the application, as documented. To
2595 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2598 * d10v, m68hc11 `regs' command deprecated
2600 The `info registers' command has been updated so that it displays the
2601 registers using a format identical to the old `regs' command.
2605 A new command, "maint set profile on/off", has been added. This command can
2606 be used to enable or disable profiling while running GDB, to profile a
2607 session or a set of commands. In addition there is a new configure switch,
2608 "--enable-profiling", which will cause GDB to be compiled with profiling
2609 data, for more informative profiling results.
2611 * Default MI syntax changed to "mi2".
2613 The default MI (machine interface) syntax, enabled by the command line
2614 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2615 "mi1", can be enabled by specifying the option "-i=mi1".
2617 Support for the original "mi0" syntax (included in GDB 5.0) has been
2620 Fix for gdb/192: removed extraneous space when displaying frame level.
2621 Fix for gdb/672: update changelist is now output in mi list format.
2622 Fix for gdb/702: a -var-assign that updates the value now shows up
2623 in a subsequent -var-update.
2625 * New native configurations.
2627 FreeBSD/amd64 x86_64-*-freebsd*
2629 * Multi-arched targets.
2631 HP/PA HPUX11 hppa*-*-hpux*
2632 Renesas M32R/D w/simulator m32r-*-elf*
2634 * OBSOLETE configurations and files
2636 Configurations that have been declared obsolete in this release have
2637 been commented out. Unless there is activity to revive these
2638 configurations, the next release of GDB will have their sources
2639 permanently REMOVED.
2641 Z8000 simulator z8k-zilog-none or z8ksim
2642 Matsushita MN10200 w/simulator mn10200-*-*
2643 H8/500 simulator h8500-hitachi-hms or h8500hms
2644 HP/PA running BSD hppa*-*-bsd*
2645 HP/PA running OSF/1 hppa*-*-osf*
2646 HP/PA Pro target hppa*-*-pro*
2647 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2648 Sequent family i[3456]86-sequent-sysv4*
2649 i[3456]86-sequent-sysv*
2650 i[3456]86-sequent-bsd*
2651 Tsqware Sparclet sparclet-*-*
2652 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2654 * REMOVED configurations and files
2657 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2658 IBM AIX PS/2 i[3456]86-*-aix
2659 i386 running Mach 3.0 i[3456]86-*-mach3*
2660 i386 running Mach i[3456]86-*-mach*
2661 i386 running OSF/1 i[3456]86-*osf1mk*
2662 HP/Apollo 68k Family m68*-apollo*-sysv*,
2664 m68*-hp-bsd*, m68*-hp-hpux*
2665 Argonaut Risc Chip (ARC) arc-*-*
2666 Mitsubishi D30V d30v-*-*
2667 Fujitsu FR30 fr30-*-elf*
2668 OS/9000 i[34]86-*-os9k
2669 I960 with MON960 i960-*-coff
2671 * MIPS $fp behavior changed
2673 The convenience variable $fp, for the MIPS, now consistently returns
2674 the address of the current frame's base. Previously, depending on the
2675 context, $fp could refer to either $sp or the current frame's base
2676 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2677 The GNU Source-Level Debugger''.
2679 *** Changes in GDB 5.3:
2681 * GNU/Linux shared library multi-threaded performance improved.
2683 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2684 `/proc', in preference to `ptrace' for memory reads. This may result
2685 in an improvement in the start-up time of multi-threaded, shared
2686 library applications when run under GDB. One GDB user writes: ``loads
2687 shared libs like mad''.
2689 * ``gdbserver'' now supports multi-threaded applications on some targets
2691 Support for debugging multi-threaded applications which use
2692 the GNU/Linux LinuxThreads package has been added for
2693 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2694 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2696 * GDB now supports C/C++ preprocessor macros.
2698 GDB now expands preprocessor macro invocations in C/C++ expressions,
2699 and provides various commands for showing macro definitions and how
2702 The new command `macro expand EXPRESSION' expands any macro
2703 invocations in expression, and shows the result.
2705 The new command `show macro MACRO-NAME' shows the definition of the
2706 macro named MACRO-NAME, and where it was defined.
2708 Most compilers don't include information about macros in the debugging
2709 information by default. In GCC 3.1, for example, you need to compile
2710 your program with the options `-gdwarf-2 -g3'. If the macro
2711 information is present in the executable, GDB will read it.
2713 * Multi-arched targets.
2715 DEC Alpha (partial) alpha*-*-*
2716 DEC VAX (partial) vax-*-*
2718 National Semiconductor NS32000 (partial) ns32k-*-*
2719 Motorola 68000 (partial) m68k-*-*
2720 Motorola MCORE mcore-*-*
2724 Fujitsu FRV architecture added by Red Hat frv*-*-*
2727 * New native configurations
2729 Alpha NetBSD alpha*-*-netbsd*
2730 SH NetBSD sh*-*-netbsdelf*
2731 MIPS NetBSD mips*-*-netbsd*
2732 UltraSPARC NetBSD sparc64-*-netbsd*
2734 * OBSOLETE configurations and files
2736 Configurations that have been declared obsolete in this release have
2737 been commented out. Unless there is activity to revive these
2738 configurations, the next release of GDB will have their sources
2739 permanently REMOVED.
2741 Mitsubishi D30V d30v-*-*
2742 OS/9000 i[34]86-*-os9k
2743 IBM AIX PS/2 i[3456]86-*-aix
2744 Fujitsu FR30 fr30-*-elf*
2745 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2746 Argonaut Risc Chip (ARC) arc-*-*
2747 i386 running Mach 3.0 i[3456]86-*-mach3*
2748 i386 running Mach i[3456]86-*-mach*
2749 i386 running OSF/1 i[3456]86-*osf1mk*
2750 HP/Apollo 68k Family m68*-apollo*-sysv*,
2752 m68*-hp-bsd*, m68*-hp-hpux*
2753 I960 with MON960 i960-*-coff
2755 * OBSOLETE languages
2757 CHILL, a Pascal like language used by telecommunications companies.
2759 * REMOVED configurations and files
2761 AMD 29k family via UDI a29k-amd-udi, udi29k
2762 A29K VxWorks a29k-*-vxworks
2763 AMD 29000 embedded, using EBMON a29k-none-none
2764 AMD 29000 embedded with COFF a29k-none-coff
2765 AMD 29000 embedded with a.out a29k-none-aout
2767 testsuite/gdb.hp/gdb.threads-hp/ directory
2769 * New command "set max-user-call-depth <nnn>"
2771 This command allows the user to limit the call depth of user-defined
2772 commands. The default is 1024.
2774 * Changes in FreeBSD/i386 native debugging.
2776 Support for the "generate-core-file" has been added.
2778 * New commands "dump", "append", and "restore".
2780 These commands allow data to be copied from target memory
2781 to a bfd-format or binary file (dump and append), and back
2782 from a file into memory (restore).
2784 * Improved "next/step" support on multi-processor Alpha Tru64.
2786 The previous single-step mechanism could cause unpredictable problems,
2787 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2788 of a software single-step mechanism prevents this.
2790 *** Changes in GDB 5.2.1:
2798 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2799 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2800 Fix, by Joel Brobecker imported from mainline.
2802 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2803 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2804 Fix, by Fred Fish, imported from mainline.
2806 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2807 Surprisingly enough, it works now.
2808 By Michal Ludvig, imported from mainline.
2810 i386 hardware watchpoint support:
2811 avoid misses on second run for some targets.
2812 By Pierre Muller, imported from mainline.
2814 *** Changes in GDB 5.2:
2816 * New command "set trust-readonly-sections on[off]".
2818 This command is a hint that tells gdb that read-only sections
2819 really are read-only (ie. that their contents will not change).
2820 In this mode, gdb will go to the object file rather than the
2821 target to read memory from read-only sections (such as ".text").
2822 This can be a significant performance improvement on some
2823 (notably embedded) targets.
2825 * New command "generate-core-file" (or "gcore").
2827 This new gdb command allows the user to drop a core file of the child
2828 process state at any time. So far it's been implemented only for
2829 GNU/Linux and Solaris, but should be relatively easily ported to other
2830 hosts. Argument is core file name (defaults to core.<pid>).
2832 * New command line option
2834 GDB now accepts --pid or -p followed by a process id.
2836 * Change in command line behavior -- corefiles vs. process ids.
2838 There is a subtle behavior in the way in which GDB handles
2839 command line arguments. The first non-flag argument is always
2840 a program to debug, but the second non-flag argument may either
2841 be a corefile or a process id. Previously, GDB would attempt to
2842 open the second argument as a corefile, and if that failed, would
2843 issue a superfluous error message and then attempt to attach it as
2844 a process. Now, if the second argument begins with a non-digit,
2845 it will be treated as a corefile. If it begins with a digit,
2846 GDB will attempt to attach it as a process, and if no such process
2847 is found, will then attempt to open it as a corefile.
2849 * Changes in ARM configurations.
2851 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2852 configuration is fully multi-arch.
2854 * New native configurations
2856 ARM NetBSD arm*-*-netbsd*
2857 x86 OpenBSD i[3456]86-*-openbsd*
2858 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2859 Sparc64 running FreeBSD sparc64-*-freebsd*
2863 Sanyo XStormy16 xstormy16-elf
2865 * OBSOLETE configurations and files
2867 Configurations that have been declared obsolete in this release have
2868 been commented out. Unless there is activity to revive these
2869 configurations, the next release of GDB will have their sources
2870 permanently REMOVED.
2872 AMD 29k family via UDI a29k-amd-udi, udi29k
2873 A29K VxWorks a29k-*-vxworks
2874 AMD 29000 embedded, using EBMON a29k-none-none
2875 AMD 29000 embedded with COFF a29k-none-coff
2876 AMD 29000 embedded with a.out a29k-none-aout
2878 testsuite/gdb.hp/gdb.threads-hp/ directory
2880 * REMOVED configurations and files
2882 TI TMS320C80 tic80-*-*
2884 PowerPC Solaris powerpcle-*-solaris*
2885 PowerPC Windows NT powerpcle-*-cygwin32
2886 PowerPC Netware powerpc-*-netware*
2887 Harris/CXUX m88k m88*-harris-cxux*
2888 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2889 ns32k-utek-sysv* ns32k-utek-*
2890 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2891 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2892 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2893 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2894 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2896 * Changes to command line processing
2898 The new `--args' feature can be used to specify command-line arguments
2899 for the inferior from gdb's command line.
2901 * Changes to key bindings
2903 There is a new `operate-and-get-next' function bound to `C-o'.
2905 *** Changes in GDB 5.1.1
2907 Fix compile problem on DJGPP.
2909 Fix a problem with floating-point registers on the i386 being
2912 Fix to stop GDB crashing on .debug_str debug info.
2914 Numerous documentation fixes.
2916 Numerous testsuite fixes.
2918 *** Changes in GDB 5.1:
2920 * New native configurations
2922 Alpha FreeBSD alpha*-*-freebsd*
2923 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2924 MIPS GNU/Linux mips*-*-linux*
2925 MIPS SGI Irix 6.x mips*-sgi-irix6*
2926 ia64 AIX ia64-*-aix*
2927 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2931 Motorola 68HC11 and 68HC12 m68hc11-elf
2933 UltraSparc running GNU/Linux sparc64-*-linux*
2935 * OBSOLETE configurations and files
2937 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2938 Harris/CXUX m88k m88*-harris-cxux*
2939 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2940 ns32k-utek-sysv* ns32k-utek-*
2941 TI TMS320C80 tic80-*-*
2943 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2944 PowerPC Solaris powerpcle-*-solaris*
2945 PowerPC Windows NT powerpcle-*-cygwin32
2946 PowerPC Netware powerpc-*-netware*
2947 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2948 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2949 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2950 Apple Macintosh (MPW) host N/A
2952 stuff.c (Program to stuff files into a specially prepared space in kdb)
2953 kdb-start.c (Main loop for the standalone kernel debugger)
2955 Configurations that have been declared obsolete in this release have
2956 been commented out. Unless there is activity to revive these
2957 configurations, the next release of GDB will have their sources
2958 permanently REMOVED.
2960 * REMOVED configurations and files
2962 Altos 3068 m68*-altos-*
2963 Convex c1-*-*, c2-*-*
2965 ARM RISCix arm-*-* (as host)
2969 * GDB has been converted to ISO C.
2971 GDB's source code has been converted to ISO C. In particular, the
2972 sources are fully protoized, and rely on standard headers being
2977 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2979 * The MI enabled by default.
2981 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2982 revised and enabled by default. Packages which use GDB as a debugging
2983 engine behind a UI or another front end are encouraged to switch to
2984 using the GDB/MI interface, instead of the old annotations interface
2985 which is now deprecated.
2987 * Support for debugging Pascal programs.
2989 GDB now includes support for debugging Pascal programs. The following
2990 main features are supported:
2992 - Pascal-specific data types such as sets;
2994 - automatic recognition of Pascal sources based on file-name
2997 - Pascal-style display of data types, variables, and functions;
2999 - a Pascal expression parser.
3001 However, some important features are not yet supported.
3003 - Pascal string operations are not supported at all;
3005 - there are some problems with boolean types;
3007 - Pascal type hexadecimal constants are not supported
3008 because they conflict with the internal variables format;
3010 - support for Pascal objects and classes is not full yet;
3012 - unlike Pascal, GDB is case-sensitive for symbol names.
3014 * Changes in completion.
3016 Commands such as `shell', `run' and `set args', which pass arguments
3017 to inferior programs, now complete on file names, similar to what
3018 users expect at the shell prompt.
3020 Commands which accept locations, such as `disassemble', `print',
3021 `breakpoint', `until', etc. now complete on filenames as well as
3022 program symbols. Thus, if you type "break foob TAB", and the source
3023 files linked into the programs include `foobar.c', that file name will
3024 be one of the candidates for completion. However, file names are not
3025 considered for completion after you typed a colon that delimits a file
3026 name from a name of a function in that file, as in "break foo.c:bar".
3028 `set demangle-style' completes on available demangling styles.
3030 * New platform-independent commands:
3032 It is now possible to define a post-hook for a command as well as a
3033 hook that runs before the command. For more details, see the
3034 documentation of `hookpost' in the GDB manual.
3036 * Changes in GNU/Linux native debugging.
3038 Support for debugging multi-threaded programs has been completely
3039 revised for all platforms except m68k and sparc. You can now debug as
3040 many threads as your system allows you to have.
3042 Attach/detach is supported for multi-threaded programs.
3044 Support for SSE registers was added for x86. This doesn't work for
3045 multi-threaded programs though.
3047 * Changes in MIPS configurations.
3049 Multi-arch support is enabled for all MIPS configurations.
3051 GDB can now be built as native debugger on SGI Irix 6.x systems for
3052 debugging n32 executables. (Debugging 64-bit executables is not yet
3055 * Unified support for hardware watchpoints in all x86 configurations.
3057 Most (if not all) native x86 configurations support hardware-assisted
3058 breakpoints and watchpoints in a unified manner. This support
3059 implements debug register sharing between watchpoints, which allows to
3060 put a virtually infinite number of watchpoints on the same address,
3061 and also supports watching regions up to 16 bytes with several debug
3064 The new maintenance command `maintenance show-debug-regs' toggles
3065 debugging print-outs in functions that insert, remove, and test
3066 watchpoints and hardware breakpoints.
3068 * Changes in the DJGPP native configuration.
3070 New command ``info dos sysinfo'' displays assorted information about
3071 the CPU, OS, memory, and DPMI server.
3073 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3074 display information about segment descriptors stored in GDT, LDT, and
3077 New commands ``info dos pde'' and ``info dos pte'' display entries
3078 from Page Directory and Page Tables (for now works with CWSDPMI only).
3079 New command ``info dos address-pte'' displays the Page Table entry for
3080 a given linear address.
3082 GDB can now pass command lines longer than 126 characters to the
3083 program being debugged (requires an update to the libdbg.a library
3084 which is part of the DJGPP development kit).
3086 DWARF2 debug info is now supported.
3088 It is now possible to `step' and `next' through calls to `longjmp'.
3090 * Changes in documentation.
3092 All GDB documentation was converted to GFDL, the GNU Free
3093 Documentation License.
3095 Tracepoints-related commands are now fully documented in the GDB
3098 TUI, the Text-mode User Interface, is now documented in the manual.
3100 Tracepoints-related commands are now fully documented in the GDB
3103 The "GDB Internals" manual now has an index. It also includes
3104 documentation of `ui_out' functions, GDB coding standards, x86
3105 hardware watchpoints, and memory region attributes.
3107 * GDB's version number moved to ``version.in''
3109 The Makefile variable VERSION has been replaced by the file
3110 ``version.in''. People creating GDB distributions should update the
3111 contents of this file.
3115 GUD support is now a standard part of the EMACS distribution.
3117 *** Changes in GDB 5.0:
3119 * Improved support for debugging FP programs on x86 targets
3121 Unified and much-improved support for debugging floating-point
3122 programs on all x86 targets. In particular, ``info float'' now
3123 displays the FP registers in the same format on all x86 targets, with
3124 greater level of detail.
3126 * Improvements and bugfixes in hardware-assisted watchpoints
3128 It is now possible to watch array elements, struct members, and
3129 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3130 on x86 targets no longer erroneously trigger when the address is
3133 * Improvements in the native DJGPP version of GDB
3135 The distribution now includes all the scripts and auxiliary files
3136 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3137 machines ``out of the box''.
3139 The DJGPP version can now debug programs that use signals. It is
3140 possible to catch signals that happened in the debuggee, deliver
3141 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3142 would kill the program being debugged.) Programs that hook hardware
3143 interrupts (keyboard, timer, etc.) can also be debugged.
3145 It is now possible to debug DJGPP programs that redirect their
3146 standard handles or switch them to raw (as opposed to cooked) mode, or
3147 even close them. The command ``run < foo > bar'' works as expected,
3148 and ``info terminal'' reports useful information about the debuggee's
3149 terminal, including raw/cooked mode, redirection, etc.
3151 The DJGPP version now uses termios functions for console I/O, which
3152 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3155 DOS-style file names with drive letters are now fully supported by
3158 It is now possible to debug DJGPP programs that switch their working
3159 directory. It is also possible to rerun the debuggee any number of
3160 times without restarting GDB; thus, you can use the same setup,
3161 breakpoints, etc. for many debugging sessions.
3163 * New native configurations
3165 ARM GNU/Linux arm*-*-linux*
3166 PowerPC GNU/Linux powerpc-*-linux*
3170 Motorola MCore mcore-*-*
3171 x86 VxWorks i[3456]86-*-vxworks*
3172 PowerPC VxWorks powerpc-*-vxworks*
3173 TI TMS320C80 tic80-*-*
3175 * OBSOLETE configurations
3177 Altos 3068 m68*-altos-*
3178 Convex c1-*-*, c2-*-*
3180 ARM RISCix arm-*-* (as host)
3183 Configurations that have been declared obsolete will be commented out,
3184 but the code will be left in place. If there is no activity to revive
3185 these configurations before the next release of GDB, the sources will
3186 be permanently REMOVED.
3188 * Gould support removed
3190 Support for the Gould PowerNode and NP1 has been removed.
3192 * New features for SVR4
3194 On SVR4 native platforms (such as Solaris), if you attach to a process
3195 without first loading a symbol file, GDB will now attempt to locate and
3196 load symbols from the running process's executable file.
3198 * Many C++ enhancements
3200 C++ support has been greatly improved. Overload resolution now works properly
3201 in almost all cases. RTTI support is on the way.
3203 * Remote targets can connect to a sub-program
3205 A popen(3) style serial-device has been added. This device starts a
3206 sub-process (such as a stand-alone simulator) and then communicates
3207 with that. The sub-program to run is specified using the syntax
3208 ``|<program> <args>'' vis:
3210 (gdb) set remotedebug 1
3211 (gdb) target extended-remote |mn10300-elf-sim program-args
3213 * MIPS 64 remote protocol
3215 A long standing bug in the mips64 remote protocol where by GDB
3216 expected certain 32 bit registers (ex SR) to be transfered as 32
3217 instead of 64 bits has been fixed.
3219 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3220 added to provide backward compatibility with older versions of GDB.
3222 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3224 The command ``set remotebinarydownload'' command has been replaced by
3225 ``set remote X-packet''. Other commands in ``set remote'' family
3226 include ``set remote P-packet''.
3228 * Breakpoint commands accept ranges.
3230 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3231 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3232 ``tracepoint passcount'' also accepts a range of tracepoints.
3234 * ``apropos'' command added.
3236 The ``apropos'' command searches through command names and
3237 documentation strings, printing out matches, making it much easier to
3238 try to find a command that does what you are looking for.
3242 A new machine oriented interface (MI) has been added to GDB. This
3243 interface is designed for debug environments running GDB as a separate
3244 process. This is part of the long term libGDB project. See the
3245 "GDB/MI" chapter of the GDB manual for further information. It can be
3246 enabled by configuring with:
3248 .../configure --enable-gdbmi
3250 *** Changes in GDB-4.18:
3252 * New native configurations
3254 HP-UX 10.20 hppa*-*-hpux10.20
3255 HP-UX 11.x hppa*-*-hpux11.0*
3256 M68K GNU/Linux m68*-*-linux*
3260 Fujitsu FR30 fr30-*-elf*
3261 Intel StrongARM strongarm-*-*
3262 Mitsubishi D30V d30v-*-*
3264 * OBSOLETE configurations
3266 Gould PowerNode, NP1 np1-*-*, pn-*-*
3268 Configurations that have been declared obsolete will be commented out,
3269 but the code will be left in place. If there is no activity to revive
3270 these configurations before the next release of GDB, the sources will
3271 be permanently REMOVED.
3275 As a compatibility experiment, GDB's source files buildsym.h and
3276 buildsym.c have been converted to pure standard C, no longer
3277 containing any K&R compatibility code. We believe that all systems in
3278 use today either come with a standard C compiler, or have a GCC port
3279 available. If this is not true, please report the affected
3280 configuration to bug-gdb@gnu.org immediately. See the README file for
3281 information about getting a standard C compiler if you don't have one
3286 GDB now uses readline 2.2.
3288 * set extension-language
3290 You can now control the mapping between filename extensions and source
3291 languages by using the `set extension-language' command. For instance,
3292 you can ask GDB to treat .c files as C++ by saying
3293 set extension-language .c c++
3294 The command `info extensions' lists all of the recognized extensions
3295 and their associated languages.
3297 * Setting processor type for PowerPC and RS/6000
3299 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3300 you can use the `set processor' command to specify what variant of the
3301 PowerPC family you are debugging. The command
3305 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3306 following PowerPC and RS6000 variants:
3308 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3309 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3311 403GC IBM PowerPC 403GC
3312 505 Motorola PowerPC 505
3313 860 Motorola PowerPC 860 or 850
3314 601 Motorola PowerPC 601
3315 602 Motorola PowerPC 602
3316 603 Motorola/IBM PowerPC 603 or 603e
3317 604 Motorola PowerPC 604 or 604e
3318 750 Motorola/IBM PowerPC 750 or 750
3320 At the moment, this command just tells GDB what to name the
3321 special-purpose processor registers. Since almost all the affected
3322 registers are inaccessible to user-level programs, this command is
3323 only useful for remote debugging in its present form.
3327 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3328 more extensive support for HP-UX. Added features include shared
3329 library support, kernel threads and hardware watchpoints for 11.00,
3330 support for HP's ANSI C and C++ compilers, and a compatibility mode
3331 for xdb and dbx commands.
3335 HP's donation includes the new concept of catchpoints, which is a
3336 generalization of the old catch command. On HP-UX, it is now possible
3337 to catch exec, fork, and vfork, as well as library loading.
3339 This means that the existing catch command has changed; its first
3340 argument now specifies the type of catch to be set up. See the
3341 output of "help catch" for a list of catchpoint types.
3343 * Debugging across forks
3345 On HP-UX, you can choose which process to debug when a fork() happens
3350 HP has donated a curses-based terminal user interface (TUI). To get
3351 it, build with --enable-tui. Although this can be enabled for any
3352 configuration, at present it only works for native HP debugging.
3354 * GDB remote protocol additions
3356 A new protocol packet 'X' that writes binary data is now available.
3357 Default behavior is to try 'X', then drop back to 'M' if the stub
3358 fails to respond. The settable variable `remotebinarydownload'
3359 allows explicit control over the use of 'X'.
3361 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3362 full 64-bit address. The command
3364 set remoteaddresssize 32
3366 can be used to revert to the old behaviour. For existing remote stubs
3367 the change should not be noticed, as the additional address information
3370 In order to assist in debugging stubs, you may use the maintenance
3371 command `packet' to send any text string to the stub. For instance,
3373 maint packet heythere
3375 sends the packet "$heythere#<checksum>". Note that it is very easy to
3376 disrupt a debugging session by sending the wrong packet at the wrong
3379 The compare-sections command allows you to compare section data on the
3380 target to what is in the executable file without uploading or
3381 downloading, by comparing CRC checksums.
3383 * Tracing can collect general expressions
3385 You may now collect general expressions at tracepoints. This requires
3386 further additions to the target-side stub; see tracepoint.c and
3387 doc/agentexpr.texi for further details.
3389 * mask-address variable for Mips
3391 For Mips targets, you may control the zeroing of the upper 32 bits of
3392 a 64-bit address by entering `set mask-address on'. This is mainly
3393 of interest to users of embedded R4xxx and R5xxx processors.
3395 * Higher serial baud rates
3397 GDB's serial code now allows you to specify baud rates 57600, 115200,
3398 230400, and 460800 baud. (Note that your host system may not be able
3399 to achieve all of these rates.)
3403 The i960 configuration now includes an initial implementation of a
3404 builtin simulator, contributed by Jim Wilson.
3407 *** Changes in GDB-4.17:
3409 * New native configurations
3411 Alpha GNU/Linux alpha*-*-linux*
3412 Unixware 2.x i[3456]86-unixware2*
3413 Irix 6.x mips*-sgi-irix6*
3414 PowerPC GNU/Linux powerpc-*-linux*
3415 PowerPC Solaris powerpcle-*-solaris*
3416 Sparc GNU/Linux sparc-*-linux*
3417 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3421 Argonaut Risc Chip (ARC) arc-*-*
3422 Hitachi H8/300S h8300*-*-*
3423 Matsushita MN10200 w/simulator mn10200-*-*
3424 Matsushita MN10300 w/simulator mn10300-*-*
3425 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3426 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3427 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3428 Mitsubishi D10V w/simulator d10v-*-*
3429 Mitsubishi M32R/D w/simulator m32r-*-elf*
3430 Tsqware Sparclet sparclet-*-*
3431 NEC V850 w/simulator v850-*-*
3433 * New debugging protocols
3435 ARM with RDI protocol arm*-*-*
3436 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3437 DDB and LSI variants of PMON protocol mips*-*-*
3438 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3439 PowerPC with SDS protocol powerpc{,le}-*-eabi
3440 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3444 All configurations can now understand and use the DWARF 2 debugging
3445 format. The choice is automatic, if the symbol file contains DWARF 2
3450 GDB now includes basic Java language support. This support is
3451 only useful with Java compilers that produce native machine code.
3453 * solib-absolute-prefix and solib-search-path
3455 For SunOS and SVR4 shared libraries, you may now set the prefix for
3456 loading absolute shared library symbol files, and the search path for
3457 locating non-absolute shared library symbol files.
3459 * Live range splitting
3461 GDB can now effectively debug code for which GCC has performed live
3462 range splitting as part of its optimization. See gdb/doc/LRS for
3463 more details on the expected format of the stabs information.
3467 GDB's support for the GNU Hurd, including thread debugging, has been
3468 updated to work with current versions of the Hurd.
3472 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3473 instruction set. ARM GDB automatically detects when Thumb
3474 instructions are in use, and adjusts disassembly and backtracing
3479 GDB's MIPS target configurations now handle the MIP16 16-bit
3484 GDB now includes support for overlays; if an executable has been
3485 linked such that multiple sections are based at the same address, GDB
3486 will decide which section to use for symbolic info. You can choose to
3487 control the decision manually, using overlay commands, or implement
3488 additional target-side support and use "overlay load-target" to bring
3489 in the overlay mapping. Do "help overlay" for more detail.
3493 The command "info symbol <address>" displays information about
3494 the symbol at the specified address.
3498 The standard remote protocol now includes an extension that allows
3499 asynchronous collection and display of trace data. This requires
3500 extensive support in the target-side debugging stub. Tracing mode
3501 includes a new interaction mode in GDB and new commands: see the
3502 file tracepoint.c for more details.
3506 Configurations for embedded MIPS now include a simulator contributed
3507 by Cygnus Solutions. The simulator supports the instruction sets
3508 of most MIPS variants.
3512 Sparc configurations may now include the ERC32 simulator contributed
3513 by the European Space Agency. The simulator is not built into
3514 Sparc targets by default; configure with --enable-sim to include it.
3518 For target configurations that may include multiple variants of a
3519 basic architecture (such as MIPS and SH), you may now set the
3520 architecture explicitly. "set arch" sets, "info arch" lists
3521 the possible architectures.
3523 *** Changes in GDB-4.16:
3525 * New native configurations
3527 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3528 M68K NetBSD m68k-*-netbsd*
3529 PowerPC AIX 4.x powerpc-*-aix*
3530 PowerPC MacOS powerpc-*-macos*
3531 PowerPC Windows NT powerpcle-*-cygwin32
3532 RS/6000 AIX 4.x rs6000-*-aix4*
3536 ARM with RDP protocol arm-*-*
3537 I960 with MON960 i960-*-coff
3538 MIPS VxWorks mips*-*-vxworks*
3539 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3540 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3542 Matra Sparclet sparclet-*-*
3546 The powerpc-eabi configuration now includes the PSIM simulator,
3547 contributed by Andrew Cagney, with assistance from Mike Meissner.
3548 PSIM is a very elaborate model of the PowerPC, including not only
3549 basic instruction set execution, but also details of execution unit
3550 performance and I/O hardware. See sim/ppc/README for more details.
3554 GDB now works with Solaris 2.5.
3556 * Windows 95/NT native
3558 GDB will now work as a native debugger on Windows 95 and Windows NT.
3559 To build it from source, you must use the "gnu-win32" environment,
3560 which uses a DLL to emulate enough of Unix to run the GNU tools.
3561 Further information, binaries, and sources are available at
3562 ftp.cygnus.com, under pub/gnu-win32.
3564 * dont-repeat command
3566 If a user-defined command includes the command `dont-repeat', then the
3567 command will not be repeated if the user just types return. This is
3568 useful if the command is time-consuming to run, so that accidental
3569 extra keystrokes don't run the same command many times.
3571 * Send break instead of ^C
3573 The standard remote protocol now includes an option to send a break
3574 rather than a ^C to the target in order to interrupt it. By default,
3575 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3577 * Remote protocol timeout
3579 The standard remote protocol includes a new variable `remotetimeout'
3580 that allows you to set the number of seconds before GDB gives up trying
3581 to read from the target. The default value is 2.
3583 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3585 By default GDB will automatically keep track of objects as they are
3586 loaded and unloaded by the dynamic linker. By using the command `set
3587 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3588 when shared library events occur, thus allowing you to set breakpoints
3589 in shared libraries which are explicitly loaded by the inferior.
3591 Note this feature does not work on hpux8. On hpux9 you must link
3592 /usr/lib/end.o into your program. This feature should work
3593 automatically on hpux10.
3595 * Irix 5.x hardware watchpoint support
3597 Irix 5 configurations now support the use of hardware watchpoints.
3599 * Mips protocol "SYN garbage limit"
3601 When debugging a Mips target using the `target mips' protocol, you
3602 may set the number of characters that GDB will ignore by setting
3603 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3604 every character. The default value is 1050.
3606 * Recording and replaying remote debug sessions
3608 If you set `remotelogfile' to the name of a file, gdb will write to it
3609 a recording of a remote debug session. This recording may then be
3610 replayed back to gdb using "gdbreplay". See gdbserver/README for
3611 details. This is useful when you have a problem with GDB while doing
3612 remote debugging; you can make a recording of the session and send it
3613 to someone else, who can then recreate the problem.
3615 * Speedups for remote debugging
3617 GDB includes speedups for downloading and stepping MIPS systems using
3618 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3619 and more efficient S-record downloading.
3621 * Memory use reductions and statistics collection
3623 GDB now uses less memory and reports statistics about memory usage.
3624 Try the `maint print statistics' command, for example.
3626 *** Changes in GDB-4.15:
3628 * Psymtabs for XCOFF
3630 The symbol reader for AIX GDB now uses partial symbol tables. This
3631 can greatly improve startup time, especially for large executables.
3633 * Remote targets use caching
3635 Remote targets now use a data cache to speed up communication with the
3636 remote side. The data cache could lead to incorrect results because
3637 it doesn't know about volatile variables, thus making it impossible to
3638 debug targets which use memory mapped I/O devices. `set remotecache
3639 off' turns the the data cache off.
3641 * Remote targets may have threads
3643 The standard remote protocol now includes support for multiple threads
3644 in the target system, using new protocol commands 'H' and 'T'. See
3645 gdb/remote.c for details.
3649 If GDB is configured with `--enable-netrom', then it will include
3650 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3651 acts as though it is a bank of ROM on the target board, but you can
3652 write into it over the network. GDB's support consists only of
3653 support for fast loading into the emulated ROM; to debug, you must use
3654 another protocol, such as standard remote protocol. The usual
3655 sequence is something like
3657 target nrom <netrom-hostname>
3659 target remote <netrom-hostname>:1235
3663 GDB now includes support for the Apple Macintosh, as a host only. It
3664 may be run as either an MPW tool or as a standalone application, and
3665 it can debug through the serial port. All the usual GDB commands are
3666 available, but to the target command, you must supply "serial" as the
3667 device type instead of "/dev/ttyXX". See mpw-README in the main
3668 directory for more information on how to build. The MPW configuration
3669 scripts */mpw-config.in support only a few targets, and only the
3670 mips-idt-ecoff target has been tested.
3674 GDB configuration now uses autoconf. This is not user-visible,
3675 but does simplify configuration and building.
3679 GDB now supports hpux10.
3681 *** Changes in GDB-4.14:
3683 * New native configurations
3685 x86 FreeBSD i[345]86-*-freebsd
3686 x86 NetBSD i[345]86-*-netbsd
3687 NS32k NetBSD ns32k-*-netbsd
3688 Sparc NetBSD sparc-*-netbsd
3692 A29K VxWorks a29k-*-vxworks
3693 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3694 CPU32 EST-300 emulator m68*-*-est*
3695 PowerPC ELF powerpc-*-elf
3698 * Alpha OSF/1 support for procfs
3700 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3701 possible to attach to running processes. As the mounting of the /proc
3702 filesystem is optional on the Alpha, GDB automatically determines
3703 the availability of /proc during startup. This can lead to problems
3704 if /proc is unmounted after GDB has been started.
3706 * Arguments to user-defined commands
3708 User commands may accept up to 10 arguments separated by whitespace.
3709 Arguments are accessed within the user command via $arg0..$arg9. A
3712 print $arg0 + $arg1 + $arg2
3714 To execute the command use:
3717 Defines the command "adder" which prints the sum of its three arguments.
3718 Note the arguments are text substitutions, so they may reference variables,
3719 use complex expressions, or even perform inferior function calls.
3721 * New `if' and `while' commands
3723 This makes it possible to write more sophisticated user-defined
3724 commands. Both commands take a single argument, which is the
3725 expression to evaluate, and must be followed by the commands to
3726 execute, one per line, if the expression is nonzero, the list being
3727 terminated by the word `end'. The `if' command list may include an
3728 `else' word, which causes the following commands to be executed only
3729 if the expression is zero.
3731 * Fortran source language mode
3733 GDB now includes partial support for Fortran 77. It will recognize
3734 Fortran programs and can evaluate a subset of Fortran expressions, but
3735 variables and functions may not be handled correctly. GDB will work
3736 with G77, but does not yet know much about symbols emitted by other
3739 * Better HPUX support
3741 Most debugging facilities now work on dynamic executables for HPPAs
3742 running hpux9 or later. You can attach to running dynamically linked
3743 processes, but by default the dynamic libraries will be read-only, so
3744 for instance you won't be able to put breakpoints in them. To change
3745 that behavior do the following before running the program:
3751 This will cause the libraries to be mapped private and read-write.
3752 To revert to the normal behavior, do this:
3758 You cannot set breakpoints or examine data in the library until after
3759 the library is loaded if the function/data symbols do not have
3762 GDB can now also read debug symbols produced by the HP C compiler on
3763 HPPAs (sorry, no C++, Fortran or 68k support).
3765 * Target byte order now dynamically selectable
3767 You can choose which byte order to use with a target system, via the
3768 commands "set endian big" and "set endian little", and you can see the
3769 current setting by using "show endian". You can also give the command
3770 "set endian auto", in which case GDB will use the byte order
3771 associated with the executable. Currently, only embedded MIPS
3772 configurations support dynamic selection of target byte order.
3774 * New DOS host serial code
3776 This version uses DPMI interrupts to handle buffered I/O, so you
3777 no longer need to run asynctsr when debugging boards connected to
3780 *** Changes in GDB-4.13:
3782 * New "complete" command
3784 This lists all the possible completions for the rest of the line, if it
3785 were to be given as a command itself. This is intended for use by emacs.
3787 * Trailing space optional in prompt
3789 "set prompt" no longer adds a space for you after the prompt you set. This
3790 allows you to set a prompt which ends in a space or one that does not.
3792 * Breakpoint hit counts
3794 "info break" now displays a count of the number of times the breakpoint
3795 has been hit. This is especially useful in conjunction with "ignore"; you
3796 can ignore a large number of breakpoint hits, look at the breakpoint info
3797 to see how many times the breakpoint was hit, then run again, ignoring one
3798 less than that number, and this will get you quickly to the last hit of
3801 * Ability to stop printing at NULL character
3803 "set print null-stop" will cause GDB to stop printing the characters of
3804 an array when the first NULL is encountered. This is useful when large
3805 arrays actually contain only short strings.
3807 * Shared library breakpoints
3809 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3810 breakpoints in shared libraries before the executable is run.
3812 * Hardware watchpoints
3814 There is a new hardware breakpoint for the watch command for sparclite
3815 targets. See gdb/sparclite/hw_breakpoint.note.
3817 Hardware watchpoints are also now supported under GNU/Linux.
3821 Annotations have been added. These are for use with graphical interfaces,
3822 and are still experimental. Currently only gdba.el uses these.
3824 * Improved Irix 5 support
3826 GDB now works properly with Irix 5.2.
3828 * Improved HPPA support
3830 GDB now works properly with the latest GCC and GAS.
3832 * New native configurations
3834 Sequent PTX4 i[34]86-sequent-ptx4
3835 HPPA running OSF/1 hppa*-*-osf*
3836 Atari TT running SVR4 m68*-*-sysv4*
3837 RS/6000 LynxOS rs6000-*-lynxos*
3841 OS/9000 i[34]86-*-os9k
3842 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3845 * Hitachi SH7000 and E7000-PC ICE support
3847 There is now support for communicating with the Hitachi E7000-PC ICE.
3848 This is available automatically when GDB is configured for the SH.
3852 As usual, a variety of small fixes and improvements, both generic
3853 and configuration-specific. See the ChangeLog for more detail.
3855 *** Changes in GDB-4.12:
3857 * Irix 5 is now supported
3861 GDB-4.12 on the HPPA has a number of changes which make it unable
3862 to debug the output from the currently released versions of GCC and
3863 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3864 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3865 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3868 *** Changes in GDB-4.11:
3870 * User visible changes:
3874 The "set remotedebug" option is now consistent between the mips remote
3875 target, remote targets using the gdb-specific protocol, UDI (AMD's
3876 debug protocol for the 29k) and the 88k bug monitor. It is now an
3877 integer specifying a debug level (normally 0 or 1, but 2 means more
3878 debugging info for the mips target).
3880 * DEC Alpha native support
3882 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3883 debug info, but GDB works fairly well with the DEC compiler and should
3884 work with a future GCC release. See the README file for a few
3885 Alpha-specific notes.
3887 * Preliminary thread implementation
3889 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3891 * LynxOS native and target support for 386
3893 This release has been hosted on LynxOS 2.2, and also can be configured
3894 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3897 * Improvements in C++ mangling/demangling.
3899 This release has much better g++ debugging, specifically in name
3900 mangling/demangling, virtual function calls, print virtual table,
3901 call methods, ...etc.
3903 *** Changes in GDB-4.10:
3905 * User visible changes:
3907 Remote debugging using the GDB-specific (`target remote') protocol now
3908 supports the `load' command. This is only useful if you have some
3909 other way of getting the stub to the target system, and you can put it
3910 somewhere in memory where it won't get clobbered by the download.
3912 Filename completion now works.
3914 When run under emacs mode, the "info line" command now causes the
3915 arrow to point to the line specified. Also, "info line" prints
3916 addresses in symbolic form (as well as hex).
3918 All vxworks based targets now support a user settable option, called
3919 vxworks-timeout. This option represents the number of seconds gdb
3920 should wait for responses to rpc's. You might want to use this if
3921 your vxworks target is, perhaps, a slow software simulator or happens
3922 to be on the far side of a thin network line.
3926 This release contains support for using a DEC alpha as a GDB host for
3927 cross debugging. Native alpha debugging is not supported yet.
3930 *** Changes in GDB-4.9:
3934 This is the first GDB release which is accompanied by a matching testsuite.
3935 The testsuite requires installation of dejagnu, which should be available
3936 via ftp from most sites that carry GNU software.
3940 'Cfront' style demangling has had its name changed to 'ARM' style, to
3941 emphasize that it was written from the specifications in the C++ Annotated
3942 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3943 disclaimers, it still generated too much confusion with users attempting to
3944 use gdb with AT&T cfront.
3948 GDB now uses a standard remote interface to a simulator library.
3949 So far, the library contains simulators for the Zilog Z8001/2, the
3950 Hitachi H8/300, H8/500 and Super-H.
3952 * New targets supported
3954 H8/300 simulator h8300-hitachi-hms or h8300hms
3955 H8/500 simulator h8500-hitachi-hms or h8500hms
3956 SH simulator sh-hitachi-hms or sh
3957 Z8000 simulator z8k-zilog-none or z8ksim
3958 IDT MIPS board over serial line mips-idt-ecoff
3960 Cross-debugging to GO32 targets is supported. It requires a custom
3961 version of the i386-stub.c module which is integrated with the
3962 GO32 memory extender.
3964 * New remote protocols
3966 MIPS remote debugging protocol.
3968 * New source languages supported
3970 This version includes preliminary support for Chill, a Pascal like language
3971 used by telecommunications companies. Chill support is also being integrated
3972 into the GNU compiler, but we don't know when it will be publically available.
3975 *** Changes in GDB-4.8:
3977 * HP Precision Architecture supported
3979 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3980 version of this support was available as a set of patches from the
3981 University of Utah. GDB does not support debugging of programs
3982 compiled with the HP compiler, because HP will not document their file
3983 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3984 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3986 Many problems in the preliminary version have been fixed.
3988 * Faster and better demangling
3990 We have improved template demangling and fixed numerous bugs in the GNU style
3991 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3992 character types (wchar_t) are now supported. Demangling of each symbol is now
3993 only done once, and is cached when the symbol table for a file is read in.
3994 This results in a small increase in memory usage for C programs, a moderate
3995 increase in memory usage for C++ programs, and a fantastic speedup in
3998 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3999 from the specifications in the Annotated Reference Manual, which AT&T's
4000 compiler does not actually implement.
4002 * G++ multiple inheritance compiler problem
4004 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4005 inheritance lattices was reworked to properly discover ambiguities. We
4006 recently found an example which causes this new algorithm to fail in a
4007 very subtle way, producing bad debug information for those classes.
4008 The file 'gcc.patch' (in this directory) can be applied to gcc to
4009 circumvent the problem. A future GCC release will contain a complete
4012 The previous G++ debug info problem (mentioned below for the gdb-4.7
4013 release) is fixed in gcc version 2.3.2.
4015 * Improved configure script
4017 The `configure' script will now attempt to guess your system type if
4018 you don't supply a host system type. The old scheme of supplying a
4019 host system triplet is preferable over using this. All the magic is
4020 done in the new `config.guess' script. Examine it for details.
4022 We have also brought our configure script much more in line with the FSF's
4023 version. It now supports the --with-xxx options. In particular,
4024 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4025 The resulting GDB will not be able to read arbitrary object file formats --
4026 only the format ``expected'' to be used on the configured target system.
4027 We hope to make this the default in a future release.
4029 * Documentation improvements
4031 There's new internal documentation on how to modify GDB, and how to
4032 produce clean changes to the code. We implore people to read it
4033 before submitting changes.
4035 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4036 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4037 `info' files are also provided. To build `info' files from scratch,
4038 you will need the latest `makeinfo' release, which will be available in
4039 a future texinfo-X.Y release.
4041 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4042 We're not sure exactly which versions have this problem, but it has
4043 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4044 or better. If that isn't possible, there is a patch in
4045 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4046 around this problem.
4050 GDB now supports array constants that can be used in expressions typed in by
4051 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4052 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4055 The new directory `gdb/sparclite' contains a program that demonstrates
4056 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4058 * New native hosts supported
4060 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4061 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4063 * New targets supported
4065 AMD 29k family via UDI a29k-amd-udi or udi29k
4067 * New file formats supported
4069 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4070 HPUX core files, and SCO 3.2v2 core files.
4074 Attaching to processes now works again; thanks for the many bug reports.
4076 We have also stomped on a bunch of core dumps caused by
4077 printf_filtered("%s") problems.
4079 We eliminated a copyright problem on the rpc and ptrace header files
4080 for VxWorks, which was discovered at the last minute during the 4.7
4081 release. You should now be able to build a VxWorks GDB.
4083 You can now interrupt gdb while an attached process is running. This
4084 will cause the attached process to stop, and give control back to GDB.
4086 We fixed problems caused by using too many file descriptors
4087 for reading symbols from object files and libraries. This was
4088 especially a problem for programs that used many (~100) shared
4091 The `step' command now only enters a subroutine if there is line number
4092 information for the subroutine. Otherwise it acts like the `next'
4093 command. Previously, `step' would enter subroutines if there was
4094 any debugging information about the routine. This avoids problems
4095 when using `cc -g1' on MIPS machines.
4097 * Internal improvements
4099 GDB's internal interfaces have been improved to make it easier to support
4100 debugging of multiple languages in the future.
4102 GDB now uses a common structure for symbol information internally.
4103 Minimal symbols (derived from linkage symbols in object files), partial
4104 symbols (from a quick scan of debug information), and full symbols
4105 contain a common subset of information, making it easier to write
4106 shared code that handles any of them.
4108 * New command line options
4110 We now accept --silent as an alias for --quiet.
4114 The memory-mapped-malloc library is now licensed under the GNU Library
4115 General Public License.
4117 *** Changes in GDB-4.7:
4119 * Host/native/target split
4121 GDB has had some major internal surgery to untangle the support for
4122 hosts and remote targets. Now, when you configure GDB for a remote
4123 target, it will no longer load in all of the support for debugging
4124 local programs on the host. When fully completed and tested, this will
4125 ensure that arbitrary host/target combinations are possible.
4127 The primary conceptual shift is to separate the non-portable code in
4128 GDB into three categories. Host specific code is required any time GDB
4129 is compiled on that host, regardless of the target. Target specific
4130 code relates to the peculiarities of the target, but can be compiled on
4131 any host. Native specific code is everything else: it can only be
4132 built when the host and target are the same system. Child process
4133 handling and core file support are two common `native' examples.
4135 GDB's use of /proc for controlling Unix child processes is now cleaner.
4136 It has been split out into a single module under the `target_ops' vector,
4137 plus two native-dependent functions for each system that uses /proc.
4139 * New hosts supported
4141 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4142 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4143 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4145 * New targets supported
4147 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4148 68030 and CPU32 m68030-*-*, m68332-*-*
4150 * New native hosts supported
4152 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4153 (386bsd is not well tested yet)
4154 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4156 * New file formats supported
4158 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4159 supports reading of `a.out.adobe' object files, which are an a.out
4160 format extended with minimal information about multiple sections.
4164 `show copying' is the same as the old `info copying'.
4165 `show warranty' is the same as `info warrantee'.
4166 These were renamed for consistency. The old commands continue to work.
4168 `info handle' is a new alias for `info signals'.
4170 You can now define pre-command hooks, which attach arbitrary command
4171 scripts to any command. The commands in the hook will be executed
4172 prior to the user's command. You can also create a hook which will be
4173 executed whenever the program stops. See gdb.texinfo.
4177 We now deal with Cfront style name mangling, and can even extract type
4178 info from mangled symbols. GDB can automatically figure out which
4179 symbol mangling style your C++ compiler uses.
4181 Calling of methods and virtual functions has been improved as well.
4185 The crash that occured when debugging Sun Ansi-C compiled binaries is
4186 fixed. This was due to mishandling of the extra N_SO stabs output
4189 We also finally got Ultrix 4.2 running in house, and fixed core file
4190 support, with help from a dozen people on the net.
4192 John M. Farrell discovered that the reason that single-stepping was so
4193 slow on all of the Mips based platforms (primarily SGI and DEC) was
4194 that we were trying to demangle and lookup a symbol used for internal
4195 purposes on every instruction that was being stepped through. Changing
4196 the name of that symbol so that it couldn't be mistaken for a C++
4197 mangled symbol sped things up a great deal.
4199 Rich Pixley sped up symbol lookups in general by getting much smarter
4200 about when C++ symbol mangling is necessary. This should make symbol
4201 completion (TAB on the command line) much faster. It's not as fast as
4202 we'd like, but it's significantly faster than gdb-4.6.
4206 A new user controllable variable 'call_scratch_address' can
4207 specify the location of a scratch area to be used when GDB
4208 calls a function in the target. This is necessary because the
4209 usual method of putting the scratch area on the stack does not work
4210 in systems that have separate instruction and data spaces.
4212 We integrated changes to support the 29k UDI (Universal Debugger
4213 Interface), but discovered at the last minute that we didn't have all
4214 of the appropriate copyright paperwork. We are working with AMD to
4215 resolve this, and hope to have it available soon.
4219 We have sped up the remote serial line protocol, especially for targets
4220 with lots of registers. It now supports a new `expedited status' ('T')
4221 message which can be used in place of the existing 'S' status message.
4222 This allows the remote stub to send only the registers that GDB
4223 needs to make a quick decision about single-stepping or conditional
4224 breakpoints, eliminating the need to fetch the entire register set for
4225 each instruction being stepped through.
4227 The GDB remote serial protocol now implements a write-through cache for
4228 registers, only re-reading the registers if the target has run.
4230 There is also a new remote serial stub for SPARC processors. You can
4231 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4232 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4233 processor with a serial port.
4237 Configure.in files have become much easier to read and modify. A new
4238 `table driven' format makes it more obvious what configurations are
4239 supported, and what files each one uses.
4243 There is a new opcodes library which will eventually contain all of the
4244 disassembly routines and opcode tables. At present, it only contains
4245 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4246 disassembler (binutils/objdump) to share these routines.
4248 The libiberty library is now copylefted under the GNU Library General
4249 Public License. This allows more liberal use, and was done so libg++
4250 can use it. This makes no difference to GDB, since the Library License
4251 grants all the rights from the General Public License.
4255 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4256 reference to the stabs symbol info used by the debugger. It is (as far
4257 as we know) the only published document on this fascinating topic. We
4258 encourage you to read it, compare it to the stabs information on your
4259 system, and send improvements on the document in general (to
4260 bug-gdb@prep.ai.mit.edu).
4262 And, of course, many bugs have been fixed.
4265 *** Changes in GDB-4.6:
4267 * Better support for C++ function names
4269 GDB now accepts as input the "demangled form" of C++ overloaded function
4270 names and member function names, and can do command completion on such names
4271 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4272 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4273 Make use of command completion, it is your friend.
4275 GDB also now accepts a variety of C++ mangled symbol formats. They are
4276 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4277 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4278 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4279 for the list of formats.
4281 * G++ symbol mangling problem
4283 Recent versions of gcc have a bug in how they emit debugging information for
4284 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4285 directory) can be applied to gcc to fix the problem. Alternatively, if you
4286 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4287 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4288 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4291 * New 'maintenance' command
4293 All of the commands related to hacking GDB internals have been moved out of
4294 the main command set, and now live behind the 'maintenance' command. This
4295 can also be abbreviated as 'mt'. The following changes were made:
4297 dump-me -> maintenance dump-me
4298 info all-breakpoints -> maintenance info breakpoints
4299 printmsyms -> maintenance print msyms
4300 printobjfiles -> maintenance print objfiles
4301 printpsyms -> maintenance print psymbols
4302 printsyms -> maintenance print symbols
4304 The following commands are new:
4306 maintenance demangle Call internal GDB demangler routine to
4307 demangle a C++ link name and prints the result.
4308 maintenance print type Print a type chain for a given symbol
4310 * Change to .gdbinit file processing
4312 We now read the $HOME/.gdbinit file before processing the argv arguments
4313 (e.g. reading symbol files or core files). This allows global parameters to
4314 be set, which will apply during the symbol reading. The ./.gdbinit is still
4315 read after argv processing.
4317 * New hosts supported
4319 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4321 GNU/Linux support i386-unknown-linux or linux
4323 We are also including code to support the HP/PA running BSD and HPUX. This
4324 is almost guaranteed not to work, as we didn't have time to test or build it
4325 for this release. We are including it so that the more adventurous (or
4326 masochistic) of you can play with it. We also had major problems with the
4327 fact that the compiler that we got from HP doesn't support the -g option.
4330 * New targets supported
4332 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4334 * More smarts about finding #include files
4336 GDB now remembers the compilation directory for all include files, and for
4337 all files from which C is generated (like yacc and lex sources). This
4338 greatly improves GDB's ability to find yacc/lex sources, and include files,
4339 especially if you are debugging your program from a directory different from
4340 the one that contains your sources.
4342 We also fixed a bug which caused difficulty with listing and setting
4343 breakpoints in include files which contain C code. (In the past, you had to
4344 try twice in order to list an include file that you hadn't looked at before.)
4346 * Interesting infernals change
4348 GDB now deals with arbitrary numbers of sections, where the symbols for each
4349 section must be relocated relative to that section's landing place in the
4350 target's address space. This work was needed to support ELF with embedded
4351 stabs used by Solaris-2.0.
4353 * Bug fixes (of course!)
4355 There have been loads of fixes for the following things:
4356 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4357 i960, stabs, DOS(GO32), procfs, etc...
4359 See the ChangeLog for details.
4361 *** Changes in GDB-4.5:
4363 * New machines supported (host and target)
4365 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4367 SGI Irix-4.x mips-sgi-irix4 or iris4
4369 * New malloc package
4371 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4372 Mmalloc is capable of handling mutiple heaps of memory. It is also
4373 capable of saving a heap to a file, and then mapping it back in later.
4374 This can be used to greatly speedup the startup of GDB by using a
4375 pre-parsed symbol table which lives in a mmalloc managed heap. For
4376 more details, please read mmalloc/mmalloc.texi.
4380 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4381 'help info proc' for details.
4383 * MIPS ecoff symbol table format
4385 The code that reads MIPS symbol table format is now supported on all hosts.
4386 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4389 * File name changes for MS-DOS
4391 Many files in the config directories have been renamed to make it easier to
4392 support GDB on MS-DOSe systems (which have very restrictive file name
4393 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4394 environment) is close to working but has some remaining problems. Note
4395 that debugging of DOS programs is not supported, due to limitations
4396 in the ``operating system'', but it can be used to host cross-debugging.
4398 * Cross byte order fixes
4400 Many fixes have been made to support cross debugging of Sparc and MIPS
4401 targets from hosts whose byte order differs.
4403 * New -mapped and -readnow options
4405 If memory-mapped files are available on your system through the 'mmap'
4406 system call, you can use the -mapped option on the `file' or
4407 `symbol-file' commands to cause GDB to write the symbols from your
4408 program into a reusable file. If the program you are debugging is
4409 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4410 Future GDB debugging sessions will notice the presence of this file,
4411 and will quickly map in symbol information from it, rather than reading
4412 the symbol table from the executable program. Using the '-mapped'
4413 option in a GDB `file' or `symbol-file' command has the same effect as
4414 starting GDB with the '-mapped' command-line option.
4416 You can cause GDB to read the entire symbol table immediately by using
4417 the '-readnow' option with any of the commands that load symbol table
4418 information (or on the GDB command line). This makes the command
4419 slower, but makes future operations faster.
4421 The -mapped and -readnow options are typically combined in order to
4422 build a `fred.syms' file that contains complete symbol information.
4423 A simple GDB invocation to do nothing but build a `.syms' file for future
4426 gdb -batch -nx -mapped -readnow programname
4428 The `.syms' file is specific to the host machine on which GDB is run.
4429 It holds an exact image of GDB's internal symbol table. It cannot be
4430 shared across multiple host platforms.
4432 * longjmp() handling
4434 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4435 siglongjmp() without losing control. This feature has not yet been ported to
4436 all systems. It currently works on many 386 platforms, all MIPS-based
4437 platforms (SGI, DECstation, etc), and Sun3/4.
4441 Preliminary work has been put in to support the new Solaris OS from Sun. At
4442 this time, it can control and debug processes, but it is not capable of
4447 As always, many many bug fixes. The major areas were with g++, and mipsread.
4448 People using the MIPS-based platforms should experience fewer mysterious
4449 crashes and trashed symbol tables.
4451 *** Changes in GDB-4.4:
4453 * New machines supported (host and target)
4455 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4457 BSD Reno on Vax vax-dec-bsd
4458 Ultrix on Vax vax-dec-ultrix
4460 * New machines supported (target)
4462 AMD 29000 embedded, using EBMON a29k-none-none
4466 GDB continues to improve its handling of C++. `References' work better.
4467 The demangler has also been improved, and now deals with symbols mangled as
4468 per the Annotated C++ Reference Guide.
4470 GDB also now handles `stabs' symbol information embedded in MIPS
4471 `ecoff' symbol tables. Since the ecoff format was not easily
4472 extensible to handle new languages such as C++, this appeared to be a
4473 good way to put C++ debugging info into MIPS binaries. This option
4474 will be supported in the GNU C compiler, version 2, when it is
4477 * New features for SVR4
4479 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4480 shared libraries. Debugging dynamically linked programs should present
4481 only minor differences from debugging statically linked programs.
4483 The `info proc' command will print out information about any process
4484 on an SVR4 system (including the one you are debugging). At the moment,
4485 it prints the address mappings of the process.
4487 If you bring up GDB on another SVR4 system, please send mail to
4488 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4490 * Better dynamic linking support in SunOS
4492 Reading symbols from shared libraries which contain debugging symbols
4493 now works properly. However, there remain issues such as automatic
4494 skipping of `transfer vector' code during function calls, which
4495 make it harder to debug code in a shared library, than to debug the
4496 same code linked statically.
4500 GDB is now using the latest `getopt' routines from the FSF. This
4501 version accepts the -- prefix for options with long names. GDB will
4502 continue to accept the old forms (-option and +option) as well.
4503 Various single letter abbreviations for options have been explicity
4504 added to the option table so that they won't get overshadowed in the
4505 future by other options that begin with the same letter.
4509 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4510 Many assorted bugs have been handled. Many more remain to be handled.
4511 See the various ChangeLog files (primarily in gdb and bfd) for details.
4514 *** Changes in GDB-4.3:
4516 * New machines supported (host and target)
4518 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4519 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4520 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4522 * Almost SCO Unix support
4524 We had hoped to support:
4525 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4526 (except for core file support), but we discovered very late in the release
4527 that it has problems with process groups that render gdb unusable. Sorry
4528 about that. I encourage people to fix it and post the fixes.
4530 * Preliminary ELF and DWARF support
4532 GDB can read ELF object files on System V Release 4, and can handle
4533 debugging records for C, in DWARF format, in ELF files. This support
4534 is preliminary. If you bring up GDB on another SVR4 system, please
4535 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4540 GDB now uses the latest `readline' library. One user-visible change
4541 is that two tabs will list possible command completions, which previously
4542 required typing M-? (meta-question mark, or ESC ?).
4546 The `stepi' bug that many of you noticed has been squashed.
4547 Many bugs in C++ have been handled. Many more remain to be handled.
4548 See the various ChangeLog files (primarily in gdb and bfd) for details.
4550 * State of the MIPS world (in case you wondered):
4552 GDB can understand the symbol tables emitted by the compilers
4553 supplied by most vendors of MIPS-based machines, including DEC. These
4554 symbol tables are in a format that essentially nobody else uses.
4556 Some versions of gcc come with an assembler post-processor called
4557 mips-tfile. This program is required if you want to do source-level
4558 debugging of gcc-compiled programs. I believe FSF does not ship
4559 mips-tfile with gcc version 1, but it will eventually come with gcc
4562 Debugging of g++ output remains a problem. g++ version 1.xx does not
4563 really support it at all. (If you're lucky, you should be able to get
4564 line numbers and stack traces to work, but no parameters or local
4565 variables.) With some work it should be possible to improve the
4568 When gcc version 2 is released, you will have somewhat better luck.
4569 However, even then you will get confusing results for inheritance and
4572 We will eventually provide full debugging of g++ output on
4573 DECstations. This will probably involve some kind of stabs-in-ecoff
4574 encapulation, but the details have not been worked out yet.
4577 *** Changes in GDB-4.2:
4579 * Improved configuration
4581 Only one copy of `configure' exists now, and it is not self-modifying.
4582 Porting BFD is simpler.
4586 The `step' and `next' commands now only stop at the first instruction
4587 of a source line. This prevents the multiple stops that used to occur
4588 in switch statements, for-loops, etc. `Step' continues to stop if a
4589 function that has debugging information is called within the line.
4593 Lots of small bugs fixed. More remain.
4595 * New host supported (not target)
4597 Intel 386 PC clone running Mach i386-none-mach
4600 *** Changes in GDB-4.1:
4602 * Multiple source language support
4604 GDB now has internal scaffolding to handle several source languages.
4605 It determines the type of each source file from its filename extension,
4606 and will switch expression parsing and number formatting to match the
4607 language of the function in the currently selected stack frame.
4608 You can also specifically set the language to be used, with
4609 `set language c' or `set language modula-2'.
4613 GDB now has preliminary support for the GNU Modula-2 compiler,
4614 currently under development at the State University of New York at
4615 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4616 continue through the fall of 1991 and into 1992.
4618 Other Modula-2 compilers are currently not supported, and attempting to
4619 debug programs compiled with them will likely result in an error as the
4620 symbol table is read. Feel free to work on it, though!
4622 There are hooks in GDB for strict type checking and range checking,
4623 in the `Modula-2 philosophy', but they do not currently work.
4627 GDB can now write to executable and core files (e.g. patch
4628 a variable's value). You must turn this switch on, specify
4629 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4630 by assigning a new value to a variable. Modifications take
4633 * Automatic SunOS shared library reading
4635 When you run your program, GDB automatically determines where its
4636 shared libraries (if any) have been loaded, and reads their symbols.
4637 The `share' command is no longer needed. This also works when
4638 examining core files.
4642 You can specify the number of lines that the `list' command shows.
4645 * New machines supported (host and target)
4647 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4648 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4649 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4651 * New hosts supported (not targets)
4653 IBM RT/PC: romp-ibm-aix or rtpc
4655 * New targets supported (not hosts)
4657 AMD 29000 embedded with COFF a29k-none-coff
4658 AMD 29000 embedded with a.out a29k-none-aout
4659 Ultracomputer remote kernel debug a29k-nyu-kern
4661 * New remote interfaces
4667 *** Changes in GDB-4.0:
4671 Wide output is wrapped at good places to make the output more readable.
4673 Gdb now supports cross-debugging from a host machine of one type to a
4674 target machine of another type. Communication with the target system
4675 is over serial lines. The ``target'' command handles connecting to the
4676 remote system; the ``load'' command will download a program into the
4677 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4678 also supports debugging of realtime processes running under VxWorks,
4679 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4680 stub on the target system.
4682 New CPUs supported include the AMD 29000 and Intel 960.
4684 GDB now reads object files and symbol tables via a ``binary file''
4685 library, which allows a single copy of GDB to debug programs of multiple
4686 object file types such as a.out and coff.
4688 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4689 refcard.dvi and refcard.ps are available to format it).
4692 * Control-Variable user interface simplified
4694 All variables that control the operation of the debugger can be set
4695 by the ``set'' command, and displayed by the ``show'' command.
4697 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4698 ``Show prompt'' produces the response:
4699 Gdb's prompt is new-gdb=>.
4701 What follows are the NEW set commands. The command ``help set'' will
4702 print a complete list of old and new set commands. ``help set FOO''
4703 will give a longer description of the variable FOO. ``show'' will show
4704 all of the variable descriptions and their current settings.
4706 confirm on/off: Enables warning questions for operations that are
4707 hard to recover from, e.g. rerunning the program while
4708 it is already running. Default is ON.
4710 editing on/off: Enables EMACS style command line editing
4711 of input. Previous lines can be recalled with
4712 control-P, the current line can be edited with control-B,
4713 you can search for commands with control-R, etc.
4716 history filename NAME: NAME is where the gdb command history
4717 will be stored. The default is .gdb_history,
4718 or the value of the environment variable
4721 history size N: The size, in commands, of the command history. The
4722 default is 256, or the value of the environment variable
4725 history save on/off: If this value is set to ON, the history file will
4726 be saved after exiting gdb. If set to OFF, the
4727 file will not be saved. The default is OFF.
4729 history expansion on/off: If this value is set to ON, then csh-like
4730 history expansion will be performed on
4731 command line input. The default is OFF.
4733 radix N: Sets the default radix for input and output. It can be set
4734 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4735 in the current radix, so "set radix 10" is always a no-op.
4737 height N: This integer value is the number of lines on a page. Default
4738 is 24, the current `stty rows'' setting, or the ``li#''
4739 setting from the termcap entry matching the environment
4742 width N: This integer value is the number of characters on a line.
4743 Default is 80, the current `stty cols'' setting, or the ``co#''
4744 setting from the termcap entry matching the environment
4747 Note: ``set screensize'' is obsolete. Use ``set height'' and
4748 ``set width'' instead.
4750 print address on/off: Print memory addresses in various command displays,
4751 such as stack traces and structure values. Gdb looks
4752 more ``symbolic'' if you turn this off; it looks more
4753 ``machine level'' with it on. Default is ON.
4755 print array on/off: Prettyprint arrays. New convenient format! Default
4758 print demangle on/off: Print C++ symbols in "source" form if on,
4761 print asm-demangle on/off: Same, for assembler level printouts
4764 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4767 * Support for Epoch Environment.
4769 The epoch environment is a version of Emacs v18 with windowing. One
4770 new command, ``inspect'', is identical to ``print'', except that if you
4771 are running in the epoch environment, the value is printed in its own
4775 * Support for Shared Libraries
4777 GDB can now debug programs and core files that use SunOS shared libraries.
4778 Symbols from a shared library cannot be referenced
4779 before the shared library has been linked with the program (this
4780 happens after you type ``run'' and before the function main() is entered).
4781 At any time after this linking (including when examining core files
4782 from dynamically linked programs), gdb reads the symbols from each
4783 shared library when you type the ``sharedlibrary'' command.
4784 It can be abbreviated ``share''.
4786 sharedlibrary REGEXP: Load shared object library symbols for files
4787 matching a unix regular expression. No argument
4788 indicates to load symbols for all shared libraries.
4790 info sharedlibrary: Status of loaded shared libraries.
4795 A watchpoint stops execution of a program whenever the value of an
4796 expression changes. Checking for this slows down execution
4797 tremendously whenever you are in the scope of the expression, but is
4798 quite useful for catching tough ``bit-spreader'' or pointer misuse
4799 problems. Some machines such as the 386 have hardware for doing this
4800 more quickly, and future versions of gdb will use this hardware.
4802 watch EXP: Set a watchpoint (breakpoint) for an expression.
4804 info watchpoints: Information about your watchpoints.
4806 delete N: Deletes watchpoint number N (same as breakpoints).
4807 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4808 enable N: Re-enables watchpoint number N (same as breakpoints).
4811 * C++ multiple inheritance
4813 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4816 * C++ exception handling
4818 Gdb now supports limited C++ exception handling. Besides the existing
4819 ability to breakpoint on an exception handler, gdb can breakpoint on
4820 the raising of an exception (before the stack is peeled back to the
4823 catch FOO: If there is a FOO exception handler in the dynamic scope,
4824 set a breakpoint to catch exceptions which may be raised there.
4825 Multiple exceptions (``catch foo bar baz'') may be caught.
4827 info catch: Lists all exceptions which may be caught in the
4828 current stack frame.
4831 * Minor command changes
4833 The command ``call func (arg, arg, ...)'' now acts like the print
4834 command, except it does not print or save a value if the function's result
4835 is void. This is similar to dbx usage.
4837 The ``up'' and ``down'' commands now always print the frame they end up
4838 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4839 frames without printing.
4841 * New directory command
4843 'dir' now adds directories to the FRONT of the source search path.
4844 The path starts off empty. Source files that contain debug information
4845 about the directory in which they were compiled can be found even
4846 with an empty path; Sun CC and GCC include this information. If GDB can't
4847 find your source file in the current directory, type "dir .".
4849 * Configuring GDB for compilation
4851 For normal use, type ``./configure host''. See README or gdb.texinfo
4854 GDB now handles cross debugging. If you are remotely debugging between
4855 two different machines, type ``./configure host -target=targ''.
4856 Host is the machine where GDB will run; targ is the machine
4857 where the program that you are debugging will run.