1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.3.1
6 * GDB now allows you to skip uninteresting functions and files when
7 stepping with the "skip function" and "skip file" commands.
9 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
10 and "show remote hardware-watchpoint-length-limit". These allows to
11 set or show the maximum length limit (in bytes) of a remote
12 target hardware watchpoint.
14 This allows e.g. to use "unlimited" hardware watchpoints with the
15 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
16 watchpoints are slower than real hardware watchpoints but are
17 significantly faster than gdb software watchpoints.
21 ** The register_pretty_printer function in module gdb.printing now takes
22 an optional `replace' argument. If True, the new printer replaces any
25 ** The "maint set python print-stack on|off" command has been
26 deprecated, and a new command: "set python print-stack on|off" has
27 replaced it. Additionally, the default for "print-stack" is now
30 ** A prompt substitution hook (prompt_hook) is now available to the
33 ** A new Python module, gdb.prompt has been added to the GDB Python
34 modules library. This module provides functionality for
35 escape sequences in prompts (used by set/show
36 extended-prompt). These escape sequences are replaced by their
39 ** Python commands and convenience-functions located in
40 'data-directory'/python/gdb/command and
41 'data-directory'/python/gdb/function are now automatically loaded
44 ** Blocks now provide four new attributes. global_block and
45 static_block will return the global and static blocks
46 respectively. is_static and is_global are boolean attributes
47 that indicate if the block is one of those two types.
49 ** Symbols now provide the "type" attribute, the type of the symbol.
51 ** The "gdb.breakpoint" function has been deprecated in favor of
54 ** Type objects for struct and union types now allow access to
55 the fields using standard Python dictionary (mapping) methods.
56 For example, "some_type['myfield']" now works, as does
59 ** A new event "gdb.new_objfile" has been added, triggered by loading a
62 ** A new function, "deep_items" has been added to the gdb.types
63 module in the GDB Python modules library. This function returns
64 an iterator over the fields of a struct or union type. Unlike
65 the standard Python "iteritems" method, it will recursively traverse
68 * libthread-db-search-path now supports two special values: $sdir and $pdir.
69 $sdir specifies the default system locations of shared libraries.
70 $pdir specifies the directory where the libpthread used by the application
73 GDB no longer looks in $sdir and $pdir after it has searched the directories
74 mentioned in libthread-db-search-path. If you want to search those
75 directories, they must be specified in libthread-db-search-path.
76 The default value of libthread-db-search-path on GNU/Linux and Solaris
77 systems is now "$sdir:$pdir".
79 $pdir is not supported by gdbserver, it is currently ignored.
80 $sdir is supported by gdbserver.
82 * New configure option --with-iconv-bin.
83 When using the internationalization support like the one in the GNU C
84 library, GDB will invoke the "iconv" program to get a list of supported
85 character sets. If this program lives in a non-standard location, one can
86 use this option to specify where to find it.
88 * When natively debugging programs on PowerPC BookE processors running
89 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
90 watchpoints, which specify a mask in addition to an address to watch.
91 The mask specifies that some bits of an address (the bits which are
92 reset in the mask) should be ignored when matching the address accessed
93 by the inferior against the watchpoint address. See the "PowerPC Embedded"
94 section in the user manual for more details.
96 * The new option --once causes GDBserver to stop listening for connections once
97 the first connection is made. The listening port used by GDBserver will
98 become available after that.
100 * New commands "info macros" and "alias" have been added.
102 * New function parameters suffix @entry specifies value of function parameter
103 at the time the function got called. Entry values are available only since
108 watch EXPRESSION mask MASK_VALUE
109 The watch command now supports the mask argument which allows creation
110 of masked watchpoints, if the current architecture supports this feature.
112 info auto-load-scripts [REGEXP]
113 This command was formerly named "maintenance print section-scripts".
114 It is now generally useful and is no longer a maintenance-only command.
116 info macro [-all] [--] MACRO
117 The info macro command has new options `-all' and `--'. The first for
118 printing all definitions of a macro. The second for explicitly specifying
119 the end of arguments and the beginning of the macro name in case the macro
120 name starts with a hyphen.
122 collect[/s] EXPRESSIONS
123 The tracepoint collect command now takes an optional modifier "/s"
124 that directs it to dereference pointer-to-character types and
125 collect the bytes of memory up to a zero byte. The behavior is
126 similar to what you see when you use the regular print command on a
127 string. An optional integer following the "/s" sets a bound on the
128 number of bytes that will be collected.
130 * Tracepoints can now be enabled and disabled at any time after a trace
131 experiment has been started using the standard "enable" and "disable"
132 commands. It is now possible to start a trace experiment with no enabled
133 tracepoints; GDB will display a warning, but will allow the experiment to
134 begin, assuming that tracepoints will be enabled as needed while the trace
137 * Fast tracepoints on 32-bit x86-architectures can now be placed at
138 locations with 4-byte instructions, when they were previously
139 limited to locations with instructions of 5 bytes or longer.
145 Set the GDB prompt, and allow escape sequences to be inserted to
146 display miscellaneous information (see 'help set extended-prompt'
147 for the list of sequences). This prompt (and any information
148 accessed through the escape sequences) is updated every time the
151 set print entry-values (both|compact|default|if-needed|no|only|preferred)
152 show print entry-values
153 Set printing of frame argument values at function entry. In some cases
154 GDB can determine the value of function argument which was passed by the
155 function caller, even if the value was modified inside the called function.
157 set debug entry-values
158 show debug entry-values
159 Control display of debugging info for determining frame argument values at
160 function entry and virtual tail call frames.
166 Dynamically enable a tracepoint in a started trace experiment.
170 Dynamically disable a tracepoint in a started trace experiment.
174 Query the minimum length of instruction at which a fast tracepoint may
177 * Dcache size (number of lines) and line-size are now runtime-configurable
178 via "set dcache line" and "set dcache line-size" commands.
182 Texas Instruments TMS320C6x tic6x-*-*
184 *** Changes in GDB 7.3.1
186 * The build failure for NetBSD and OpenBSD targets have now been fixed.
188 *** Changes in GDB 7.3
190 * GDB has a new command: "thread find [REGEXP]".
191 It finds the thread id whose name, target id, or thread extra info
192 matches the given regular expression.
194 * The "catch syscall" command now works on mips*-linux* targets.
196 * The -data-disassemble MI command now supports modes 2 and 3 for
197 dumping the instruction opcodes.
199 * New command line options
201 -data-directory DIR Specify DIR as the "data-directory".
202 This is mostly for testing purposes.
204 * The "maint set python auto-load on|off" command has been renamed to
205 "set auto-load-scripts on|off".
207 * GDB has a new command: "set directories".
208 It is like the "dir" command except that it replaces the
209 source path list instead of augmenting it.
211 * GDB now understands thread names.
213 On GNU/Linux, "info threads" will display the thread name as set by
214 prctl or pthread_setname_np.
216 There is also a new command, "thread name", which can be used to
217 assign a name internally for GDB to display.
220 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
221 has been integrated into GDB.
225 ** The function gdb.Write now accepts an optional keyword 'stream'.
226 This keyword, when provided, will direct the output to either
227 stdout, stderr, or GDB's logging output.
229 ** Parameters can now be be sub-classed in Python, and in particular
230 you may implement the get_set_doc and get_show_doc functions.
231 This improves how Parameter set/show documentation is processed
232 and allows for more dynamic content.
234 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
235 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
236 have an is_valid method.
238 ** Breakpoints can now be sub-classed in Python, and in particular
239 you may implement a 'stop' function that is executed each time
240 the inferior reaches that breakpoint.
242 ** New function gdb.lookup_global_symbol looks up a global symbol.
244 ** GDB values in Python are now callable if the value represents a
245 function. For example, if 'some_value' represents a function that
246 takes two integer parameters and returns a value, you can call
247 that function like so:
249 result = some_value (10,20)
251 ** Module gdb.types has been added.
252 It contains a collection of utilities for working with gdb.Types objects:
253 get_basic_type, has_field, make_enum_dict.
255 ** Module gdb.printing has been added.
256 It contains utilities for writing and registering pretty-printers.
257 New classes: PrettyPrinter, SubPrettyPrinter,
258 RegexpCollectionPrettyPrinter.
259 New function: register_pretty_printer.
261 ** New commands "info pretty-printers", "enable pretty-printer" and
262 "disable pretty-printer" have been added.
264 ** gdb.parameter("directories") is now available.
266 ** New function gdb.newest_frame returns the newest frame in the
269 ** The gdb.InferiorThread class has a new "name" attribute. This
270 holds the thread's name.
272 ** Python Support for Inferior events.
273 Python scripts can add observers to be notified of events
274 occurring in the process being debugged.
275 The following events are currently supported:
276 - gdb.events.cont Continue event.
277 - gdb.events.exited Inferior exited event.
278 - gdb.events.stop Signal received, and Breakpoint hit events.
282 ** GDB now puts template parameters in scope when debugging in an
283 instantiation. For example, if you have:
285 template<int X> int func (void) { return X; }
287 then if you step into func<5>, "print X" will show "5". This
288 feature requires proper debuginfo support from the compiler; it
289 was added to GCC 4.5.
291 ** The motion commands "next", "finish", "until", and "advance" now
292 work better when exceptions are thrown. In particular, GDB will
293 no longer lose control of the inferior; instead, the GDB will
294 stop the inferior at the point at which the exception is caught.
295 This functionality requires a change in the exception handling
296 code that was introduced in GCC 4.5.
298 * GDB now follows GCC's rules on accessing volatile objects when
299 reading or writing target state during expression evaluation.
300 One notable difference to prior behavior is that "print x = 0"
301 no longer generates a read of x; the value of the assignment is
302 now always taken directly from the value being assigned.
304 * GDB now has some support for using labels in the program's source in
305 linespecs. For instance, you can use "advance label" to continue
306 execution to a label.
308 * GDB now has support for reading and writing a new .gdb_index
309 section. This section holds a fast index of DWARF debugging
310 information and can be used to greatly speed up GDB startup and
311 operation. See the documentation for `save gdb-index' for details.
313 * The "watch" command now accepts an optional "-location" argument.
314 When used, this causes GDB to watch the memory referred to by the
315 expression. Such a watchpoint is never deleted due to it going out
318 * GDB now supports thread debugging of core dumps on GNU/Linux.
320 GDB now activates thread debugging using the libthread_db library
321 when debugging GNU/Linux core dumps, similarly to when debugging
322 live processes. As a result, when debugging a core dump file, GDB
323 is now able to display pthread_t ids of threads. For example, "info
324 threads" shows the same output as when debugging the process when it
325 was live. In earlier releases, you'd see something like this:
328 * 1 LWP 6780 main () at main.c:10
330 While now you see this:
333 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
335 It is also now possible to inspect TLS variables when debugging core
338 When debugging a core dump generated on a machine other than the one
339 used to run GDB, you may need to point GDB at the correct
340 libthread_db library with the "set libthread-db-search-path"
341 command. See the user manual for more details on this command.
343 * When natively debugging programs on PowerPC BookE processors running
344 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
345 which stop execution of the inferior whenever it executes an instruction
346 at any address within the specified range. See the "PowerPC Embedded"
347 section in the user manual for more details.
349 * New features in the GDB remote stub, GDBserver
351 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
352 and i686 LynxOS (version 5.x).
354 ** GDBserver is now supported on Blackfin Linux.
356 * New native configurations
358 ia64 HP-UX ia64-*-hpux*
362 Analog Devices, Inc. Blackfin Processor bfin-*
364 * Ada task switching is now supported on sparc-elf targets when
365 debugging a program using the Ravenscar Profile. For more information,
366 see the "Tasking Support when using the Ravenscar Profile" section
367 in the GDB user manual.
369 * Guile support was removed.
371 * New features in the GNU simulator
373 ** The --map-info flag lists all known core mappings.
375 ** CFI flashes may be simulated via the "cfi" device.
377 *** Changes in GDB 7.2
379 * Shared library support for remote targets by default
381 When GDB is configured for a generic, non-OS specific target, like
382 for example, --target=arm-eabi or one of the many *-*-elf targets,
383 GDB now queries remote stubs for loaded shared libraries using the
384 `qXfer:libraries:read' packet. Previously, shared library support
385 was always disabled for such configurations.
389 ** Argument Dependent Lookup (ADL)
391 In C++ ADL lookup directs function search to the namespaces of its
392 arguments even if the namespace has not been imported.
402 Here the compiler will search for `foo' in the namespace of 'b'
403 and find A::foo. GDB now supports this. This construct is commonly
404 used in the Standard Template Library for operators.
406 ** Improved User Defined Operator Support
408 In addition to member operators, GDB now supports lookup of operators
409 defined in a namespace and imported with a `using' directive, operators
410 defined in the global scope, operators imported implicitly from an
411 anonymous namespace, and the ADL operators mentioned in the previous
413 GDB now also supports proper overload resolution for all the previously
414 mentioned flavors of operators.
416 ** static const class members
418 Printing of static const class members that are initialized in the
419 class definition has been fixed.
421 * Windows Thread Information Block access.
423 On Windows targets, GDB now supports displaying the Windows Thread
424 Information Block (TIB) structure. This structure is visible either
425 by using the new command `info w32 thread-information-block' or, by
426 dereferencing the new convenience variable named `$_tlb', a
427 thread-specific pointer to the TIB. This feature is also supported
428 when remote debugging using GDBserver.
432 Static tracepoints are calls in the user program into a tracing
433 library. One such library is a port of the LTTng kernel tracer to
434 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
435 When debugging with GDBserver, GDB now supports combining the GDB
436 tracepoint machinery with such libraries. For example: the user can
437 use GDB to probe a static tracepoint marker (a call from the user
438 program into the tracing library) with the new "strace" command (see
439 "New commands" below). This creates a "static tracepoint" in the
440 breakpoint list, that can be manipulated with the same feature set
441 as fast and regular tracepoints. E.g., collect registers, local and
442 global variables, collect trace state variables, and define
443 tracepoint conditions. In addition, the user can collect extra
444 static tracepoint marker specific data, by collecting the new
445 $_sdata internal variable. When analyzing the trace buffer, you can
446 inspect $_sdata like any other variable available to GDB. For more
447 information, see the "Tracepoints" chapter in GDB user manual. New
448 remote packets have been defined to support static tracepoints, see
449 the "New remote packets" section below.
451 * Better reconstruction of tracepoints after disconnected tracing
453 GDB will attempt to download the original source form of tracepoint
454 definitions when starting a trace run, and then will upload these
455 upon reconnection to the target, resulting in a more accurate
456 reconstruction of the tracepoints that are in use on the target.
460 You can now exercise direct control over the ways that GDB can
461 affect your program. For instance, you can disallow the setting of
462 breakpoints, so that the program can run continuously (assuming
463 non-stop mode). In addition, the "observer" variable is available
464 to switch all of the different controls; in observer mode, GDB
465 cannot affect the target's behavior at all, which is useful for
466 tasks like diagnosing live systems in the field.
468 * The new convenience variable $_thread holds the number of the
475 Return the address of the Windows Thread Information Block of a given thread.
479 In response to several of the tracepoint packets, the target may now
480 also respond with a number of intermediate `qRelocInsn' request
481 packets before the final result packet, to have GDB handle
482 relocating an instruction to execute at a different address. This
483 is particularly useful for stubs that support fast tracepoints. GDB
484 reports support for this feature in the qSupported packet.
488 List static tracepoint markers in the target program.
492 List static tracepoint markers at a given address in the target
495 qXfer:statictrace:read
497 Read the static trace data collected (by a `collect $_sdata'
498 tracepoint action). The remote stub reports support for this packet
499 to gdb's qSupported query.
503 Send the current settings of GDB's permission flags.
507 Send part of the source (textual) form of a tracepoint definition,
508 which includes location, conditional, and action list.
510 * The source command now accepts a -s option to force searching for the
511 script in the source search path even if the script name specifies
514 * New features in the GDB remote stub, GDBserver
516 - GDBserver now support tracepoints (including fast tracepoints, and
517 static tracepoints). The feature is currently supported by the
518 i386-linux and amd64-linux builds. See the "Tracepoints support
519 in gdbserver" section in the manual for more information.
521 GDBserver JIT compiles the tracepoint's conditional agent
522 expression bytecode into native code whenever possible for low
523 overhead dynamic tracepoints conditionals. For such tracepoints,
524 an expression that examines program state is evaluated when the
525 tracepoint is reached, in order to determine whether to capture
526 trace data. If the condition is simple and false, processing the
527 tracepoint finishes very quickly and no data is gathered.
529 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
530 for static tracepoints support.
532 - GDBserver now supports x86_64 Windows 64-bit debugging.
534 * GDB now sends xmlRegisters= in qSupported packet to indicate that
535 it understands register description.
537 * The --batch flag now disables pagination and queries.
539 * X86 general purpose registers
541 GDB now supports reading/writing byte, word and double-word x86
542 general purpose registers directly. This means you can use, say,
543 $ah or $ax to refer, respectively, to the byte register AH and
544 16-bit word register AX that are actually portions of the 32-bit
545 register EAX or 64-bit register RAX.
547 * The `commands' command now accepts a range of breakpoints to modify.
548 A plain `commands' following a command that creates multiple
549 breakpoints affects all the breakpoints set by that command. This
550 applies to breakpoints set by `rbreak', and also applies when a
551 single `break' command creates multiple breakpoints (e.g.,
552 breakpoints on overloaded c++ functions).
554 * The `rbreak' command now accepts a filename specification as part of
555 its argument, limiting the functions selected by the regex to those
556 in the specified file.
558 * Support for remote debugging Windows and SymbianOS shared libraries
559 from Unix hosts has been improved. Non Windows GDB builds now can
560 understand target reported file names that follow MS-DOS based file
561 system semantics, such as file names that include drive letters and
562 use the backslash character as directory separator. This makes it
563 possible to transparently use the "set sysroot" and "set
564 solib-search-path" on Unix hosts to point as host copies of the
565 target's shared libraries. See the new command "set
566 target-file-system-kind" described below, and the "Commands to
567 specify files" section in the user manual for more information.
571 eval template, expressions...
572 Convert the values of one or more expressions under the control
573 of the string template to a command line, and call it.
575 set target-file-system-kind unix|dos-based|auto
576 show target-file-system-kind
577 Set or show the assumed file system kind for target reported file
580 save breakpoints <filename>
581 Save all current breakpoint definitions to a file suitable for use
582 in a later debugging session. To read the saved breakpoint
583 definitions, use the `source' command.
585 `save tracepoints' is a new alias for `save-tracepoints'. The latter
588 info static-tracepoint-markers
589 Display information about static tracepoint markers in the target.
591 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
592 Define a static tracepoint by probing a marker at the given
593 function, line, address, or marker ID.
597 Enable and disable observer mode.
599 set may-write-registers on|off
600 set may-write-memory on|off
601 set may-insert-breakpoints on|off
602 set may-insert-tracepoints on|off
603 set may-insert-fast-tracepoints on|off
604 set may-interrupt on|off
605 Set individual permissions for GDB effects on the target. Note that
606 some of these settings can have undesirable or surprising
607 consequences, particularly when changed in the middle of a session.
608 For instance, disabling the writing of memory can prevent
609 breakpoints from being inserted, cause single-stepping to fail, or
610 even crash your program, if you disable after breakpoints have been
611 inserted. However, GDB should not crash.
613 set record memory-query on|off
614 show record memory-query
615 Control whether to stop the inferior if memory changes caused
616 by an instruction cannot be recorded.
621 The disassemble command now supports "start,+length" form of two arguments.
625 ** GDB now provides a new directory location, called the python directory,
626 where Python scripts written for GDB can be installed. The location
627 of that directory is <data-directory>/python, where <data-directory>
628 is the GDB data directory. For more details, see section `Scripting
629 GDB using Python' in the manual.
631 ** The GDB Python API now has access to breakpoints, symbols, symbol
632 tables, program spaces, inferiors, threads and frame's code blocks.
633 Additionally, GDB Parameters can now be created from the API, and
634 manipulated via set/show in the CLI.
636 ** New functions gdb.target_charset, gdb.target_wide_charset,
637 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
639 ** New exception gdb.GdbError.
641 ** Pretty-printers are now also looked up in the current program space.
643 ** Pretty-printers can now be individually enabled and disabled.
645 ** GDB now looks for names of Python scripts to auto-load in a
646 special section named `.debug_gdb_scripts', in addition to looking
647 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
649 * Tracepoint actions were unified with breakpoint commands. In particular,
650 there are no longer differences in "info break" output for breakpoints and
651 tracepoints and the "commands" command can be used for both tracepoints and
656 ARM Symbian arm*-*-symbianelf*
658 * D language support.
659 GDB now supports debugging programs written in the D programming
662 * GDB now supports the extended ptrace interface for PowerPC which is
663 available since Linux kernel version 2.6.34. This automatically enables
664 any hardware breakpoints and additional hardware watchpoints available in
665 the processor. The old ptrace interface exposes just one hardware
666 watchpoint and no hardware breakpoints.
668 * GDB is now able to use the Data Value Compare (DVC) register available on
669 embedded PowerPC processors to implement in hardware simple watchpoint
670 conditions of the form:
672 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
674 This works in native GDB running on Linux kernels with the extended ptrace
675 interface mentioned above.
677 *** Changes in GDB 7.1
683 GDB now supports importing of namespaces in C++. This enables the
684 user to inspect variables from imported namespaces. Support for
685 namepace aliasing has also been added. So, if a namespace is
686 aliased in the current scope (e.g. namepace C=A; ) the user can
687 print variables using the alias (e.g. (gdb) print C::x).
691 All known bugs relating to the printing of virtual base class were
692 fixed. It is now possible to call overloaded static methods using a
697 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
698 and reinterpret_cast<> are now handled by the C++ expression parser.
702 Xilinx MicroBlaze microblaze-*-*
707 Xilinx MicroBlaze microblaze
710 * Multi-program debugging.
712 GDB now has support for multi-program (a.k.a. multi-executable or
713 multi-exec) debugging. This allows for debugging multiple inferiors
714 simultaneously each running a different program under the same GDB
715 session. See "Debugging Multiple Inferiors and Programs" in the
716 manual for more information. This implied some user visible changes
717 in the multi-inferior support. For example, "info inferiors" now
718 lists inferiors that are not running yet or that have exited
719 already. See also "New commands" and "New options" below.
721 * New tracing features
723 GDB's tracepoint facility now includes several new features:
725 ** Trace state variables
727 GDB tracepoints now include support for trace state variables, which
728 are variables managed by the target agent during a tracing
729 experiment. They are useful for tracepoints that trigger each
730 other, so for instance one tracepoint can count hits in a variable,
731 and then a second tracepoint has a condition that is true when the
732 count reaches a particular value. Trace state variables share the
733 $-syntax of GDB convenience variables, and can appear in both
734 tracepoint actions and condition expressions. Use the "tvariable"
735 command to create, and "info tvariables" to view; see "Trace State
736 Variables" in the manual for more detail.
740 GDB now includes an option for defining fast tracepoints, which
741 targets may implement more efficiently, such as by installing a jump
742 into the target agent rather than a trap instruction. The resulting
743 speedup can be by two orders of magnitude or more, although the
744 tradeoff is that some program locations on some target architectures
745 might not allow fast tracepoint installation, for instance if the
746 instruction to be replaced is shorter than the jump. To request a
747 fast tracepoint, use the "ftrace" command, with syntax identical to
748 the regular trace command.
750 ** Disconnected tracing
752 It is now possible to detach GDB from the target while it is running
753 a trace experiment, then reconnect later to see how the experiment
754 is going. In addition, a new variable disconnected-tracing lets you
755 tell the target agent whether to continue running a trace if the
756 connection is lost unexpectedly.
760 GDB now has the ability to save the trace buffer into a file, and
761 then use that file as a target, similarly to you can do with
762 corefiles. You can select trace frames, print data that was
763 collected in them, and use tstatus to display the state of the
764 tracing run at the moment that it was saved. To create a trace
765 file, use "tsave <filename>", and to use it, do "target tfile
768 ** Circular trace buffer
770 You can ask the target agent to handle the trace buffer as a
771 circular buffer, discarding the oldest trace frames to make room for
772 newer ones, by setting circular-trace-buffer to on. This feature may
773 not be available for all target agents.
778 The disassemble command, when invoked with two arguments, now requires
779 the arguments to be comma-separated.
782 The info variables command now displays variable definitions. Files
783 which only declare a variable are not shown.
786 The source command is now capable of sourcing Python scripts.
787 This feature is dependent on the debugger being build with Python
790 Related to this enhancement is also the introduction of a new command
791 "set script-extension" (see below).
793 * New commands (for set/show, see "New options" below)
795 record save [<FILENAME>]
796 Save a file (in core file format) containing the process record
797 execution log for replay debugging at a later time.
799 record restore <FILENAME>
800 Restore the process record execution log that was saved at an
801 earlier time, for replay debugging.
803 add-inferior [-copies <N>] [-exec <FILENAME>]
806 clone-inferior [-copies <N>] [ID]
807 Make a new inferior ready to execute the same program another
813 maint info program-spaces
814 List the program spaces loaded into GDB.
816 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
817 show remote interrupt-sequence
818 Allow the user to select one of ^C, a BREAK signal or BREAK-g
819 as the sequence to the remote target in order to interrupt the execution.
820 Ctrl-C is a default. Some system prefers BREAK which is high level of
821 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
822 Magic SysRq g. It is BREAK signal and character 'g'.
824 set remote interrupt-on-connect [on | off]
825 show remote interrupt-on-connect
826 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
827 remote target when gdb connects to it. This is needed when you debug
830 set remotebreak [on | off]
832 Deprecated. Use "set/show remote interrupt-sequence" instead.
834 tvariable $NAME [ = EXP ]
835 Create or modify a trace state variable.
838 List trace state variables and their values.
840 delete tvariable $NAME ...
841 Delete one or more trace state variables.
844 Evaluate the given expressions without collecting anything into the
845 trace buffer. (Valid in tracepoint actions only.)
847 ftrace FN / FILE:LINE / *ADDR
848 Define a fast tracepoint at the given function, line, or address.
850 * New expression syntax
852 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
853 GDB now parses 0b101010 identically with 42.
857 set follow-exec-mode new|same
858 show follow-exec-mode
859 Control whether GDB reuses the same inferior across an exec call or
860 creates a new one. This is useful to be able to restart the old
861 executable after the inferior having done an exec call.
863 set default-collect EXPR, ...
865 Define a list of expressions to be collected at each tracepoint.
866 This is a useful way to ensure essential items are not overlooked,
867 such as registers or a critical global variable.
869 set disconnected-tracing
870 show disconnected-tracing
871 If set to 1, the target is instructed to continue tracing if it
872 loses its connection to GDB. If 0, the target is to stop tracing
875 set circular-trace-buffer
876 show circular-trace-buffer
877 If set to on, the target is instructed to use a circular trace buffer
878 and discard the oldest trace frames instead of stopping the trace due
879 to a full trace buffer. If set to off, the trace stops when the buffer
880 fills up. Some targets may not support this.
882 set script-extension off|soft|strict
883 show script-extension
884 If set to "off", the debugger does not perform any script language
885 recognition, and all sourced files are assumed to be GDB scripts.
886 If set to "soft" (the default), files are sourced according to
887 filename extension, falling back to GDB scripts if the first
889 If set to "strict", files are sourced according to filename extension.
891 set ada trust-PAD-over-XVS on|off
892 show ada trust-PAD-over-XVS
893 If off, activate a workaround against a bug in the debugging information
894 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
895 the GCC sources for more information about the GNAT encoding and
896 PAD types in particular). It is always safe to set this option to
897 off, but this introduces a slight performance penalty. The default
900 * Python API Improvements
902 ** GDB provides the new class gdb.LazyString. This is useful in
903 some pretty-printing cases. The new method gdb.Value.lazy_string
904 provides a simple way to create objects of this type.
906 ** The fields returned by gdb.Type.fields now have an
907 `is_base_class' attribute.
909 ** The new method gdb.Type.range returns the range of an array type.
911 ** The new method gdb.parse_and_eval can be used to parse and
912 evaluate an expression.
917 Define a trace state variable.
920 Get the current value of a trace state variable.
923 Set desired tracing behavior upon disconnection.
926 Set the trace buffer to be linear or circular.
929 Get data about the tracepoints currently in use.
933 Process record now works correctly with hardware watchpoints.
935 Multiple bug fixes have been made to the mips-irix port, making it
936 much more reliable. In particular:
937 - Debugging threaded applications is now possible again. Previously,
938 GDB would hang while starting the program, or while waiting for
939 the program to stop at a breakpoint.
940 - Attaching to a running process no longer hangs.
941 - An error occurring while loading a core file has been fixed.
942 - Changing the value of the PC register now works again. This fixes
943 problems observed when using the "jump" command, or when calling
944 a function from GDB, or even when assigning a new value to $pc.
945 - With the "finish" and "return" commands, the return value for functions
946 returning a small array is now correctly printed.
947 - It is now possible to break on shared library code which gets executed
948 during a shared library init phase (code executed while executing
949 their .init section). Previously, the breakpoint would have no effect.
950 - GDB is now able to backtrace through the signal handler for
951 non-threaded programs.
953 PIE (Position Independent Executable) programs debugging is now supported.
954 This includes debugging execution of PIC (Position Independent Code) shared
955 libraries although for that, it should be possible to run such libraries as an
958 *** Changes in GDB 7.0
960 * GDB now has an interface for JIT compilation. Applications that
961 dynamically generate code can create symbol files in memory and register
962 them with GDB. For users, the feature should work transparently, and
963 for JIT developers, the interface is documented in the GDB manual in the
964 "JIT Compilation Interface" chapter.
966 * Tracepoints may now be conditional. The syntax is as for
967 breakpoints; either an "if" clause appended to the "trace" command,
968 or the "condition" command is available. GDB sends the condition to
969 the target for evaluation using the same bytecode format as is used
970 for tracepoint actions.
972 * The disassemble command now supports: an optional /r modifier, print the
973 raw instructions in hex as well as in symbolic form, and an optional /m
974 modifier to print mixed source+assembly.
976 * Process record and replay
978 In a architecture environment that supports ``process record and
979 replay'', ``process record and replay'' target can record a log of
980 the process execution, and replay it with both forward and reverse
983 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
984 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
985 set execution-direction {forward|reverse}, for targets that support
988 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
989 feature is available with a native GDB running on kernel version
992 * GDB now has support for multi-byte and wide character sets on the
993 target. Strings whose character type is wchar_t, char16_t, or
994 char32_t are now correctly printed. GDB supports wide- and unicode-
995 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
996 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
997 `printf'. This feature requires iconv to work properly; if your
998 system does not have a working iconv, GDB can use GNU libiconv. See
999 the installation instructions for more information.
1001 * GDB now supports automatic retrieval of shared library files from
1002 remote targets. To use this feature, specify a system root that begins
1003 with the `remote:' prefix, either via the `set sysroot' command or via
1004 the `--with-sysroot' configure-time option.
1006 * "info sharedlibrary" now takes an optional regex of libraries to show,
1007 and it now reports if a shared library has no debugging information.
1009 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1010 now complete on file names.
1012 * When completing in expressions, gdb will attempt to limit
1013 completions to allowable structure or union fields, where appropriate.
1014 For instance, consider:
1016 # struct example { int f1; double f2; };
1017 # struct example variable;
1020 If the user types TAB at the end of this command line, the available
1021 completions will be "f1" and "f2".
1023 * Inlined functions are now supported. They show up in backtraces, and
1024 the "step", "next", and "finish" commands handle them automatically.
1026 * GDB now supports the token-splicing (##) and stringification (#)
1027 operators when expanding macros. It also supports variable-arity
1030 * GDB now supports inspecting extra signal information, exported by
1031 the new $_siginfo convenience variable. The feature is currently
1032 implemented on linux ARM, i386 and amd64.
1034 * GDB can now display the VFP floating point registers and NEON vector
1035 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1036 can provide these registers (requires Linux 2.6.30 or later). Remote
1037 and simulator targets may also provide them.
1039 * New remote packets
1042 Search memory for a sequence of bytes.
1045 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1046 operation over reliable transport links. Use of this packet is
1047 controlled by the `set remote noack-packet' command.
1050 Kill the process with the specified process ID. Use this in preference
1051 to `k' when multiprocess protocol extensions are supported.
1054 Obtains additional operating system information
1058 Read or write additional signal information.
1060 * Removed remote protocol undocumented extension
1062 An undocumented extension to the remote protocol's `S' stop reply
1063 packet that permited the stub to pass a process id was removed.
1064 Remote servers should use the `T' stop reply packet instead.
1066 * GDB now supports multiple function calling conventions according to the
1067 DWARF-2 DW_AT_calling_convention function attribute.
1069 * The SH target utilizes the aforementioned change to distinguish between gcc
1070 and Renesas calling convention. It also adds the new CLI commands
1071 `set/show sh calling-convention'.
1073 * GDB can now read compressed debug sections, as produced by GNU gold
1074 with the --compress-debug-sections=zlib flag.
1076 * 64-bit core files are now supported on AIX.
1078 * Thread switching is now supported on Tru64.
1080 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1081 which will be allocated using malloc later in program execution.
1083 * The qXfer:libraries:read remote procotol packet now allows passing a
1084 list of section offsets.
1086 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1087 conditions handling signals delivered during attach or thread creation
1088 have also been fixed.
1090 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1091 From the user's standpoint, all unqualified instances of True and False
1092 are treated as the standard definitions, regardless of context.
1094 * GDB now parses C++ symbol and type names more flexibly. For
1097 template<typename T> class C { };
1100 GDB will now correctly handle all of:
1102 ptype C<char const *>
1103 ptype C<char const*>
1104 ptype C<const char *>
1105 ptype C<const char*>
1107 * New features in the GDB remote stub, gdbserver
1109 - The "--wrapper" command-line argument tells gdbserver to use a
1110 wrapper program to launch programs for debugging.
1112 - On PowerPC and S/390 targets, it is now possible to use a single
1113 gdbserver executable to debug both 32-bit and 64-bit programs.
1114 (This requires gdbserver itself to be built as a 64-bit executable.)
1116 - gdbserver uses the new noack protocol mode for TCP connections to
1117 reduce communications latency, if also supported and enabled in GDB.
1119 - Support for the sparc64-linux-gnu target is now included in
1122 - The amd64-linux build of gdbserver now supports debugging both
1123 32-bit and 64-bit programs.
1125 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1126 now support hardware watchpoints, and will use them automatically
1131 GDB now has support for scripting using Python. Whether this is
1132 available is determined at configure time.
1134 New GDB commands can now be written in Python.
1136 * Ada tasking support
1138 Ada tasks can now be inspected in GDB. The following commands have
1142 Print the list of Ada tasks.
1144 Print detailed information about task number N.
1146 Print the task number of the current task.
1148 Switch the context of debugging to task number N.
1150 * Support for user-defined prefixed commands. The "define" command can
1151 add new commands to existing prefixes, e.g. "target".
1153 * Multi-inferior, multi-process debugging.
1155 GDB now has generalized support for multi-inferior debugging. See
1156 "Debugging Multiple Inferiors" in the manual for more information.
1157 Although availability still depends on target support, the command
1158 set is more uniform now. The GNU/Linux specific multi-forks support
1159 has been migrated to this new framework. This implied some user
1160 visible changes; see "New commands" and also "Removed commands"
1163 * Target descriptions can now describe the target OS ABI. See the
1164 "Target Description Format" section in the user manual for more
1167 * Target descriptions can now describe "compatible" architectures
1168 to indicate that the target can execute applications for a different
1169 architecture in addition to those for the main target architecture.
1170 See the "Target Description Format" section in the user manual for
1173 * Multi-architecture debugging.
1175 GDB now includes general supports for debugging applications on
1176 hybrid systems that use more than one single processor architecture
1177 at the same time. Each such hybrid architecture still requires
1178 specific support to be added. The only hybrid architecture supported
1179 in this version of GDB is the Cell Broadband Engine.
1181 * GDB now supports integrated debugging of Cell/B.E. applications that
1182 use both the PPU and SPU architectures. To enable support for hybrid
1183 Cell/B.E. debugging, you need to configure GDB to support both the
1184 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1185 --enable-targets configure option.
1187 * Non-stop mode debugging.
1189 For some targets, GDB now supports an optional mode of operation in
1190 which you can examine stopped threads while other threads continue
1191 to execute freely. This is referred to as non-stop mode, with the
1192 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1193 section in the user manual for more information.
1195 To be able to support remote non-stop debugging, a remote stub needs
1196 to implement the non-stop mode remote protocol extensions, as
1197 described in the "Remote Non-Stop" section of the user manual. The
1198 GDB remote stub, gdbserver, has been adjusted to support these
1199 extensions on linux targets.
1201 * New commands (for set/show, see "New options" below)
1203 catch syscall [NAME(S) | NUMBER(S)]
1204 Catch system calls. Arguments, which should be names of system
1205 calls or their numbers, mean catch only those syscalls. Without
1206 arguments, every syscall will be caught. When the inferior issues
1207 any of the specified syscalls, GDB will stop and announce the system
1208 call, both when it is called and when its call returns. This
1209 feature is currently available with a native GDB running on the
1210 Linux Kernel, under the following architectures: x86, x86_64,
1211 PowerPC and PowerPC64.
1213 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1215 Search memory for a sequence of bytes.
1217 maint set python print-stack
1218 maint show python print-stack
1219 Show a stack trace when an error is encountered in a Python script.
1222 Invoke CODE by passing it to the Python interpreter.
1227 These allow macros to be defined, undefined, and listed
1231 Show operating system information about processes.
1234 List the inferiors currently under GDB's control.
1237 Switch focus to inferior number NUM.
1240 Detach from inferior number NUM.
1243 Kill inferior number NUM.
1247 set spu stop-on-load
1248 show spu stop-on-load
1249 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1251 set spu auto-flush-cache
1252 show spu auto-flush-cache
1253 Control whether to automatically flush the software-managed cache
1254 during Cell/B.E. debugging.
1256 set sh calling-convention
1257 show sh calling-convention
1258 Control the calling convention used when calling SH target functions.
1261 show debug timestamp
1262 Control display of timestamps with GDB debugging output.
1264 set disassemble-next-line
1265 show disassemble-next-line
1266 Control display of disassembled source lines or instructions when
1269 set remote noack-packet
1270 show remote noack-packet
1271 Set/show the use of remote protocol QStartNoAckMode packet. See above
1272 under "New remote packets."
1274 set remote query-attached-packet
1275 show remote query-attached-packet
1276 Control use of remote protocol `qAttached' (query-attached) packet.
1278 set remote read-siginfo-object
1279 show remote read-siginfo-object
1280 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1283 set remote write-siginfo-object
1284 show remote write-siginfo-object
1285 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1288 set remote reverse-continue
1289 show remote reverse-continue
1290 Control use of remote protocol 'bc' (reverse-continue) packet.
1292 set remote reverse-step
1293 show remote reverse-step
1294 Control use of remote protocol 'bs' (reverse-step) packet.
1296 set displaced-stepping
1297 show displaced-stepping
1298 Control displaced stepping mode. Displaced stepping is a way to
1299 single-step over breakpoints without removing them from the debuggee.
1300 Also known as "out-of-line single-stepping".
1303 show debug displaced
1304 Control display of debugging info for displaced stepping.
1306 maint set internal-error
1307 maint show internal-error
1308 Control what GDB does when an internal error is detected.
1310 maint set internal-warning
1311 maint show internal-warning
1312 Control what GDB does when an internal warning is detected.
1317 Use a wrapper program to launch programs for debugging.
1319 set multiple-symbols (all|ask|cancel)
1320 show multiple-symbols
1321 The value of this variable can be changed to adjust the debugger behavior
1322 when an expression or a breakpoint location contains an ambiguous symbol
1323 name (an overloaded function name, for instance).
1325 set breakpoint always-inserted
1326 show breakpoint always-inserted
1327 Keep breakpoints always inserted in the target, as opposed to inserting
1328 them when resuming the target, and removing them when the target stops.
1329 This option can improve debugger performance on slow remote targets.
1331 set arm fallback-mode (arm|thumb|auto)
1332 show arm fallback-mode
1333 set arm force-mode (arm|thumb|auto)
1335 These commands control how ARM GDB determines whether instructions
1336 are ARM or Thumb. The default for both settings is auto, which uses
1337 the current CPSR value for instructions without symbols; previous
1338 versions of GDB behaved as if "set arm fallback-mode arm".
1340 set disable-randomization
1341 show disable-randomization
1342 Standalone programs run with the virtual address space randomization enabled
1343 by default on some platforms. This option keeps the addresses stable across
1344 multiple debugging sessions.
1348 Control whether other threads are stopped or not when some thread hits
1353 Requests that asynchronous execution is enabled in the target, if available.
1354 In this case, it's possible to resume target in the background, and interact
1355 with GDB while the target is running. "show target-async" displays the
1356 current state of asynchronous execution of the target.
1358 set target-wide-charset
1359 show target-wide-charset
1360 The target-wide-charset is the name of the character set that GDB
1361 uses when printing characters whose type is wchar_t.
1363 set tcp auto-retry (on|off)
1365 set tcp connect-timeout
1366 show tcp connect-timeout
1367 These commands allow GDB to retry failed TCP connections to a remote stub
1368 with a specified timeout period; this is useful if the stub is launched
1369 in parallel with GDB but may not be ready to accept connections immediately.
1371 set libthread-db-search-path
1372 show libthread-db-search-path
1373 Control list of directories which GDB will search for appropriate
1376 set schedule-multiple (on|off)
1377 show schedule-multiple
1378 Allow GDB to resume all threads of all processes or only threads of
1379 the current process.
1383 Use more aggressive caching for accesses to the stack. This improves
1384 performance of remote debugging (particularly backtraces) without
1385 affecting correctness.
1387 set interactive-mode (on|off|auto)
1388 show interactive-mode
1389 Control whether GDB runs in interactive mode (on) or not (off).
1390 When in interactive mode, GDB waits for the user to answer all
1391 queries. Otherwise, GDB does not wait and assumes the default
1392 answer. When set to auto (the default), GDB determines which
1393 mode to use based on the stdin settings.
1398 For program forks, this is replaced by the new more generic `info
1399 inferiors' command. To list checkpoints, you can still use the
1400 `info checkpoints' command, which was an alias for the `info forks'
1404 Replaced by the new `inferior' command. To switch between
1405 checkpoints, you can still use the `restart' command, which was an
1406 alias for the `fork' command.
1409 This is removed, since some targets don't have a notion of
1410 processes. To switch between processes, you can still use the
1411 `inferior' command using GDB's own inferior number.
1414 For program forks, this is replaced by the new more generic `kill
1415 inferior' command. To delete a checkpoint, you can still use the
1416 `delete checkpoint' command, which was an alias for the `delete
1420 For program forks, this is replaced by the new more generic `detach
1421 inferior' command. To detach a checkpoint, you can still use the
1422 `detach checkpoint' command, which was an alias for the `detach
1425 * New native configurations
1427 x86/x86_64 Darwin i[34567]86-*-darwin*
1429 x86_64 MinGW x86_64-*-mingw*
1433 Lattice Mico32 lm32-*
1434 x86 DICOS i[34567]86-*-dicos*
1435 x86_64 DICOS x86_64-*-dicos*
1438 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1439 (mingw32ce) debugging.
1445 These commands were actually not implemented on any target.
1447 *** Changes in GDB 6.8
1449 * New native configurations
1451 NetBSD/hppa hppa*-*netbsd*
1452 Xtensa GNU/Linux xtensa*-*-linux*
1456 NetBSD/hppa hppa*-*-netbsd*
1457 Xtensa GNU/Lunux xtensa*-*-linux*
1459 * Change in command line behavior -- corefiles vs. process ids.
1461 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1462 attaching to process NUMBER fails, GDB no longer attempts to open a
1463 core file named NUMBER. Attaching to a program using the -c option
1464 is no longer supported. Instead, use the '-p' or '--pid' options.
1466 * GDB can now be built as a native debugger for debugging Windows x86
1467 (mingw32) Portable Executable (PE) programs.
1469 * Pending breakpoints no longer change their number when their address
1472 * GDB now supports breakpoints with multiple locations,
1473 including breakpoints on C++ constructors, inside C++ templates,
1474 and in inlined functions.
1476 * GDB's ability to debug optimized code has been improved. GDB more
1477 accurately identifies function bodies and lexical blocks that occupy
1478 more than one contiguous range of addresses.
1480 * Target descriptions can now describe registers for PowerPC.
1482 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1483 registers on PowerPC targets.
1485 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1486 targets even when the libthread_db library is not available.
1488 * The GDB remote stub, gdbserver, now supports the new file transfer
1489 commands (remote put, remote get, and remote delete).
1491 * The GDB remote stub, gdbserver, now supports run and attach in
1492 extended-remote mode.
1494 * hppa*64*-*-hpux11* target broken
1495 The debugger is unable to start a program and fails with the following
1496 error: "Error trying to get information about dynamic linker".
1497 The gdb-6.7 release is also affected.
1499 * GDB now supports the --enable-targets= configure option to allow
1500 building a single GDB executable that supports multiple remote
1501 target architectures.
1503 * GDB now supports debugging C and C++ programs which use the
1504 Decimal Floating Point extension. In addition, the PowerPC target
1505 now has a set of pseudo-registers to inspect decimal float values
1506 stored in two consecutive float registers.
1508 * The -break-insert MI command can optionally create pending
1511 * Improved support for debugging Ada
1512 Many improvements to the Ada language support have been made. These
1514 - Better support for Ada2005 interface types
1515 - Improved handling of arrays and slices in general
1516 - Better support for Taft-amendment types
1517 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1519 - Improved command completion in Ada
1522 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1527 set print frame-arguments (all|scalars|none)
1528 show print frame-arguments
1529 The value of this variable can be changed to control which argument
1530 values should be printed by the debugger when displaying a frame.
1535 Transfer files to and from a remote target, and delete remote files.
1542 Transfer files to and from a remote target, and delete remote files.
1544 * New remote packets
1551 Open, close, read, write, and delete files on the remote system.
1554 Attach to an existing process on the remote system, in extended-remote
1558 Run a new process on the remote system, in extended-remote mode.
1560 *** Changes in GDB 6.7
1562 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1563 bfd, libiberty and opcodes, as revealed by static analysis donated by
1564 Coverity, Inc. (http://scan.coverity.com).
1566 * When looking up multiply-defined global symbols, GDB will now prefer the
1567 symbol definition in the current shared library if it was built using the
1568 -Bsymbolic linker option.
1570 * When the Text User Interface (TUI) is not configured, GDB will now
1571 recognize the -tui command-line option and print a message that the TUI
1574 * The GDB remote stub, gdbserver, now has lower overhead for high
1575 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1577 * GDB for MIPS targets now autodetects whether a remote target provides
1578 32-bit or 64-bit register values.
1580 * Support for C++ member pointers has been improved.
1582 * GDB now understands XML target descriptions, which specify the
1583 target's overall architecture. GDB can read a description from
1584 a local file or over the remote serial protocol.
1586 * Vectors of single-byte data use a new integer type which is not
1587 automatically displayed as character or string data.
1589 * The /s format now works with the print command. It displays
1590 arrays of single-byte integers and pointers to single-byte integers
1593 * Target descriptions can now describe target-specific registers,
1594 for architectures which have implemented the support (currently
1595 only ARM, M68K, and MIPS).
1597 * GDB and the GDB remote stub, gdbserver, now support the XScale
1600 * The GDB remote stub, gdbserver, has been updated to support
1601 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1602 has been rewritten to use the standard GDB remote protocol.
1604 * GDB can now step into C++ functions which are called through thunks.
1606 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1608 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1609 layout. It also supports a TextSeg= and DataSeg= response when only
1610 segment base addresses (rather than offsets) are available.
1612 * The /i format now outputs any trailing branch delay slot instructions
1613 immediately following the last instruction within the count specified.
1615 * The GDB remote protocol "T" stop reply packet now supports a
1616 "library" response. Combined with the new "qXfer:libraries:read"
1617 packet, this response allows GDB to debug shared libraries on targets
1618 where the operating system manages the list of loaded libraries (e.g.
1619 Windows and SymbianOS).
1621 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1622 (DLLs) on Windows and Windows CE targets.
1624 * GDB now supports a faster verification that a .debug file matches its binary
1625 according to its build-id signature, if the signature is present.
1631 Enable or disable hardware flow control (RTS/CTS) on the serial port
1632 when debugging using remote targets.
1634 set mem inaccessible-by-default
1635 show mem inaccessible-by-default
1636 If the target supplies a memory map, for instance via the remote
1637 protocol's "qXfer:memory-map:read" packet, setting this variable
1638 prevents GDB from accessing memory outside the memory map. This
1639 is useful for targets with memory mapped registers or which react
1640 badly to accesses of unmapped address space.
1642 set breakpoint auto-hw
1643 show breakpoint auto-hw
1644 If the target supplies a memory map, for instance via the remote
1645 protocol's "qXfer:memory-map:read" packet, setting this variable
1646 lets GDB use hardware breakpoints automatically for memory regions
1647 where it can not use software breakpoints. This covers both the
1648 "break" command and internal breakpoints used for other commands
1649 including "next" and "finish".
1652 catch exception unhandled
1653 Stop the program execution when Ada exceptions are raised.
1656 Stop the program execution when an Ada assertion failed.
1660 Set an alternate system root for target files. This is a more
1661 general version of "set solib-absolute-prefix", which is now
1662 an alias to "set sysroot".
1665 Provide extended SPU facility status information. This set of
1666 commands is available only when debugging the Cell/B.E. SPU
1669 * New native configurations
1671 OpenBSD/sh sh*-*openbsd*
1674 unset tdesc filename
1676 Use the specified local file as an XML target description, and do
1677 not query the target for its built-in description.
1681 OpenBSD/sh sh*-*-openbsd*
1682 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1683 Toshiba Media Processor mep-elf
1685 * New remote packets
1688 Ignore the specified signals; pass them directly to the debugged program
1689 without stopping other threads or reporting them to GDB.
1691 qXfer:features:read:
1692 Read an XML target description from the target, which describes its
1697 Read or write contents of an spufs file on the target system. These
1698 packets are available only on the Cell/B.E. SPU architecture.
1700 qXfer:libraries:read:
1701 Report the loaded shared libraries. Combined with new "T" packet
1702 response, this packet allows GDB to debug shared libraries on
1703 targets where the operating system manages the list of loaded
1704 libraries (e.g. Windows and SymbianOS).
1708 Support for these obsolete configurations has been removed.
1716 i[34567]86-*-lynxos*
1717 i[34567]86-*-netware*
1718 i[34567]86-*-sco3.2v5*
1719 i[34567]86-*-sco3.2v4*
1721 i[34567]86-*-sysv4.2*
1724 i[34567]86-*-unixware2*
1725 i[34567]86-*-unixware*
1734 * Other removed features
1741 Various m68k-only ROM monitors.
1748 Various Renesas ROM monitors and debugging interfaces for SH and
1753 Support for a Macraigor serial interface to on-chip debugging.
1754 GDB does not directly support the newer parallel or USB
1759 A debug information format. The predecessor to DWARF 2 and
1760 DWARF 3, which are still supported.
1762 Support for the HP aCC compiler on HP-UX/PA-RISC
1764 SOM-encapsulated symbolic debugging information, automatic
1765 invocation of pxdb, and the aCC custom C++ ABI. This does not
1766 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1767 with aCC can still be debugged on an assembly level.
1769 MIPS ".pdr" sections
1771 A MIPS-specific format used to describe stack frame layout
1772 in debugging information.
1776 GDB could work with an older version of Guile to debug
1777 the interpreter and Scheme programs running in it.
1779 set mips stack-arg-size
1780 set mips saved-gpreg-size
1782 Use "set mips abi" to control parameter passing for MIPS.
1784 *** Changes in GDB 6.6
1789 Cell Broadband Engine SPU spu-elf
1791 * GDB can now be configured as a cross-debugger targeting native Windows
1792 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1793 running on a Windows system over TCP/IP to debug Windows programs.
1795 * The GDB remote stub, gdbserver, has been updated to support Windows and
1796 Cygwin debugging. Both single-threaded and multi-threaded programs are
1799 * The "set trust-readonly-sections" command works again. This command was
1800 broken in GDB 6.3, 6.4, and 6.5.
1802 * The "load" command now supports writing to flash memory, if the remote
1803 stub provides the required support.
1805 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1806 longer requires symbolic debug information (e.g. DWARF-2).
1811 unset substitute-path
1812 show substitute-path
1813 Manage a list of substitution rules that GDB uses to rewrite the name
1814 of the directories where the sources are located. This can be useful
1815 for instance when the sources were moved to a different location
1816 between compilation and debugging.
1820 Print each CLI command as it is executed. Each command is prefixed with
1821 a number of `+' symbols representing the nesting depth.
1822 The source command now has a `-v' option to enable the same feature.
1826 The ARM Demon monitor support (RDP protocol, "target rdp").
1828 Kernel Object Display, an embedded debugging feature which only worked with
1829 an obsolete version of Cisco IOS.
1831 The 'set download-write-size' and 'show download-write-size' commands.
1833 * New remote packets
1836 Tell a stub about GDB client features, and request remote target features.
1837 The first feature implemented is PacketSize, which allows the target to
1838 specify the size of packets it can handle - to minimize the number of
1839 packets required and improve performance when connected to a remote
1843 Fetch an OS auxilliary vector from the remote stub. This packet is a
1844 more efficient replacement for qPart:auxv:read.
1846 qXfer:memory-map:read:
1847 Fetch a memory map from the remote stub, including information about
1848 RAM, ROM, and flash memory devices.
1853 Erase and program a flash memory device.
1855 * Removed remote packets
1858 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1859 used it, and only gdbserver implemented it.
1861 *** Changes in GDB 6.5
1865 Renesas M32C/M16C m32c-elf
1867 Morpho Technologies ms1 ms1-elf
1871 init-if-undefined Initialize a convenience variable, but
1872 only if it doesn't already have a value.
1874 The following commands are presently only implemented for native GNU/Linux:
1876 checkpoint Save a snapshot of the program state.
1878 restart <n> Return the program state to a
1879 previously saved state.
1881 info checkpoints List currently saved checkpoints.
1883 delete-checkpoint <n> Delete a previously saved checkpoint.
1885 set|show detach-on-fork Tell gdb whether to detach from a newly
1886 forked process, or to keep debugging it.
1888 info forks List forks of the user program that
1889 are available to be debugged.
1891 fork <n> Switch to debugging one of several
1892 forks of the user program that are
1893 available to be debugged.
1895 delete-fork <n> Delete a fork from the list of forks
1896 that are available to be debugged (and
1897 kill the forked process).
1899 detach-fork <n> Delete a fork from the list of forks
1900 that are available to be debugged (and
1901 allow the process to continue).
1905 Morpho Technologies ms2 ms1-elf
1907 * Improved Windows host support
1909 GDB now builds as a cross debugger hosted on i686-mingw32, including
1910 native console support, and remote communications using either
1911 network sockets or serial ports.
1913 * Improved Modula-2 language support
1915 GDB can now print most types in the Modula-2 syntax. This includes:
1916 basic types, set types, record types, enumerated types, range types,
1917 pointer types and ARRAY types. Procedure var parameters are correctly
1918 printed and hexadecimal addresses and character constants are also
1919 written in the Modula-2 syntax. Best results can be obtained by using
1920 GNU Modula-2 together with the -gdwarf-2 command line option.
1924 The ARM rdi-share module.
1926 The Netware NLM debug server.
1928 *** Changes in GDB 6.4
1930 * New native configurations
1932 OpenBSD/arm arm*-*-openbsd*
1933 OpenBSD/mips64 mips64-*-openbsd*
1937 Morpho Technologies ms1 ms1-elf
1939 * New command line options
1941 --batch-silent As for --batch, but totally silent.
1942 --return-child-result The debugger will exist with the same value
1943 the child (debugged) program exited with.
1944 --eval-command COMMAND, -ex COMMAND
1945 Execute a single GDB CLI command. This may be
1946 specified multiple times and in conjunction
1947 with the --command (-x) option.
1949 * Deprecated commands removed
1951 The following commands, that were deprecated in 2000, have been
1955 set|show arm disassembly-flavor set|show arm disassembler
1956 othernames set arm disassembler
1957 set|show remotedebug set|show debug remote
1958 set|show archdebug set|show debug arch
1959 set|show eventdebug set|show debug event
1962 * New BSD user-level threads support
1964 It is now possible to debug programs using the user-level threads
1965 library on OpenBSD and FreeBSD. Currently supported (target)
1968 FreeBSD/amd64 x86_64-*-freebsd*
1969 FreeBSD/i386 i386-*-freebsd*
1970 OpenBSD/i386 i386-*-openbsd*
1972 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1973 are not yet supported.
1975 * New support for Matsushita MN10300 w/sim added
1976 (Work in progress). mn10300-elf.
1978 * REMOVED configurations and files
1980 VxWorks and the XDR protocol *-*-vxworks
1981 Motorola MCORE mcore-*-*
1982 National Semiconductor NS32000 ns32k-*-*
1984 * New "set print array-indexes" command
1986 After turning this setting "on", GDB prints the index of each element
1987 when displaying arrays. The default is "off" to preserve the previous
1990 * VAX floating point support
1992 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1994 * User-defined command support
1996 In addition to using $arg0..$arg9 for argument passing, it is now possible
1997 to use $argc to determine now many arguments have been passed. See the
1998 section on user-defined commands in the user manual for more information.
2000 *** Changes in GDB 6.3:
2002 * New command line option
2004 GDB now accepts -l followed by a number to set the timeout for remote
2007 * GDB works with GCC -feliminate-dwarf2-dups
2009 GDB now supports a more compact representation of DWARF-2 debug
2010 information using DW_FORM_ref_addr references. These are produced
2011 by GCC with the option -feliminate-dwarf2-dups and also by some
2012 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2013 to use -feliminate-dwarf2-dups.
2015 * Internationalization
2017 When supported by the host system, GDB will be built with
2018 internationalization (libintl). The task of marking up the sources is
2019 continued, we're looking forward to our first translation.
2023 Initial support for debugging programs compiled with the GNAT
2024 implementation of the Ada programming language has been integrated
2025 into GDB. In this release, support is limited to expression evaluation.
2027 * New native configurations
2029 GNU/Linux/m32r m32r-*-linux-gnu
2033 GDB's remote protocol now includes support for the 'p' packet. This
2034 packet is used to fetch individual registers from a remote inferior.
2036 * END-OF-LIFE registers[] compatibility module
2038 GDB's internal register infrastructure has been completely rewritten.
2039 The new infrastructure making possible the implementation of key new
2040 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2043 GDB 6.3 will be the last release to include the the registers[]
2044 compatibility module that allowed out-of-date configurations to
2045 continue to work. This change directly impacts the following
2055 powerpc bdm protocol
2057 Unless there is activity to revive these configurations, they will be
2058 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2060 * OBSOLETE configurations and files
2062 Configurations that have been declared obsolete in this release have
2063 been commented out. Unless there is activity to revive these
2064 configurations, the next release of GDB will have their sources
2065 permanently REMOVED.
2074 *** Changes in GDB 6.2.1:
2076 * MIPS `break main; run' gave an heuristic-fence-post warning
2078 When attempting to run even a simple program, a warning about
2079 heuristic-fence-post being hit would be reported. This problem has
2082 * MIPS IRIX 'long double' crashed GDB
2084 When examining a long double variable, GDB would get a segmentation
2085 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2086 IRIX long double values).
2090 A bug in the VAX stack code was causing problems with the "next"
2091 command. This problem has been fixed.
2093 *** Changes in GDB 6.2:
2095 * Fix for ``many threads''
2097 On GNU/Linux systems that use the NPTL threads library, a program
2098 rapidly creating and deleting threads would confuse GDB leading to the
2101 ptrace: No such process.
2102 thread_db_get_info: cannot get thread info: generic error
2104 This problem has been fixed.
2106 * "-async" and "-noasync" options removed.
2108 Support for the broken "-noasync" option has been removed (it caused
2111 * New ``start'' command.
2113 This command runs the program until the begining of the main procedure.
2115 * New BSD Kernel Data Access Library (libkvm) interface
2117 Using ``target kvm'' it is now possible to debug kernel core dumps and
2118 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2119 platforms. Currently supported (native-only) configurations are:
2121 FreeBSD/amd64 x86_64-*-freebsd*
2122 FreeBSD/i386 i?86-*-freebsd*
2123 NetBSD/i386 i?86-*-netbsd*
2124 NetBSD/m68k m68*-*-netbsd*
2125 NetBSD/sparc sparc-*-netbsd*
2126 OpenBSD/amd64 x86_64-*-openbsd*
2127 OpenBSD/i386 i?86-*-openbsd*
2128 OpenBSD/m68k m68*-openbsd*
2129 OpenBSD/sparc sparc-*-openbsd*
2131 * Signal trampoline code overhauled
2133 Many generic problems with GDB's signal handling code have been fixed.
2134 These include: backtraces through non-contiguous stacks; recognition
2135 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2136 call; backtrace through a signal trampoline; step into and out of
2137 signal handlers; and single-stepping in the signal trampoline.
2139 Please note that kernel bugs are a limiting factor here. These
2140 features have been shown to work on an s390 GNU/Linux system that
2141 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2143 * Cygwin support for DWARF 2 added.
2145 * New native configurations
2147 GNU/Linux/hppa hppa*-*-linux*
2148 OpenBSD/hppa hppa*-*-openbsd*
2149 OpenBSD/m68k m68*-*-openbsd*
2150 OpenBSD/m88k m88*-*-openbsd*
2151 OpenBSD/powerpc powerpc-*-openbsd*
2152 NetBSD/vax vax-*-netbsd*
2153 OpenBSD/vax vax-*-openbsd*
2155 * END-OF-LIFE frame compatibility module
2157 GDB's internal frame infrastructure has been completely rewritten.
2158 The new infrastructure making it possible to support key new features
2159 including DWARF 2 Call Frame Information. To aid in the task of
2160 migrating old configurations to this new infrastructure, a
2161 compatibility module, that allowed old configurations to continue to
2162 work, was also included.
2164 GDB 6.2 will be the last release to include this frame compatibility
2165 module. This change directly impacts the following configurations:
2175 Unless there is activity to revive these configurations, they will be
2176 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2178 * REMOVED configurations and files
2180 Sun 3, running SunOS 3 m68*-*-sunos3*
2181 Sun 3, running SunOS 4 m68*-*-sunos4*
2182 Sun 2, running SunOS 3 m68000-*-sunos3*
2183 Sun 2, running SunOS 4 m68000-*-sunos4*
2184 Motorola 680x0 running LynxOS m68*-*-lynxos*
2185 AT&T 3b1/Unix pc m68*-att-*
2186 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2187 decstation mips-dec-* mips-little-*
2188 riscos mips-*-riscos* mips-*-sysv*
2189 sonymips mips-sony-*
2190 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2192 *** Changes in GDB 6.1.1:
2194 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2196 The TUI (Text-mode User Interface) is now built as part of a default
2197 GDB configuration. It is enabled by either selecting the TUI with the
2198 command line option "-i=tui" or by running the separate "gdbtui"
2199 program. For more information on the TUI, see the manual "Debugging
2202 * Pending breakpoint support (also included in GDB 6.1)
2204 Support has been added to allow you to specify breakpoints in shared
2205 libraries that have not yet been loaded. If a breakpoint location
2206 cannot be found, and the "breakpoint pending" option is set to auto,
2207 GDB queries you if you wish to make the breakpoint pending on a future
2208 shared-library load. If and when GDB resolves the breakpoint symbol,
2209 the pending breakpoint is removed as one or more regular breakpoints
2212 Pending breakpoints are very useful for GCJ Java debugging.
2214 * Fixed ISO-C build problems
2216 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2217 non ISO-C code that stopped them being built using a more strict ISO-C
2218 compiler (e.g., IBM's C compiler).
2220 * Fixed build problem on IRIX 5
2222 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2223 wasn't able to compile compile on an IRIX 5 system.
2225 * Added execute permission to gdb/gdbserver/configure
2227 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2228 permission. This bug would cause configure to fail on a number of
2229 systems (Solaris, IRIX). Ref: server/519.
2231 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2233 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2234 has been updated to use constant array sizes.
2236 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2238 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2239 its generated DWARF Call Frame Info. This encoding was causing GDB to
2240 panic, that panic has been fixed. Ref: gdb/1628.
2242 * Fixed a problem when examining parameters in shared library code.
2244 When examining parameters in optimized shared library code generated
2245 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2246 not available''. GDB now correctly displays the variable's value.
2248 *** Changes in GDB 6.1:
2250 * Removed --with-mmalloc
2252 Support for the mmalloc memory manager has been removed, as it
2253 conflicted with the internal gdb byte cache.
2255 * Changes in AMD64 configurations
2257 The AMD64 target now includes the %cs and %ss registers. As a result
2258 the AMD64 remote protocol has changed; this affects the floating-point
2259 and SSE registers. If you rely on those registers for your debugging,
2260 you should upgrade gdbserver on the remote side.
2262 * Revised SPARC target
2264 The SPARC target has been completely revised, incorporating the
2265 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2266 support for LynxOS and SunOS 4 has been dropped. Calling functions
2267 from within GDB on operating systems with a non-executable stack
2268 (Solaris, OpenBSD) now works.
2272 GDB has a new C++ demangler which does a better job on the mangled
2273 names generated by current versions of g++. It also runs faster, so
2274 with this and other changes gdb should now start faster on large C++
2277 * DWARF 2 Location Expressions
2279 GDB support for location expressions has been extended to support function
2280 arguments and frame bases. Older versions of GDB could crash when they
2283 * C++ nested types and namespaces
2285 GDB's support for nested types and namespaces in C++ has been
2286 improved, especially if you use the DWARF 2 debugging format. (This
2287 is the default for recent versions of GCC on most platforms.)
2288 Specifically, if you have a class "Inner" defined within a class or
2289 namespace "Outer", then GDB realizes that the class's name is
2290 "Outer::Inner", not simply "Inner". This should greatly reduce the
2291 frequency of complaints about not finding RTTI symbols. In addition,
2292 if you are stopped at inside of a function defined within a namespace,
2293 GDB modifies its name lookup accordingly.
2295 * New native configurations
2297 NetBSD/amd64 x86_64-*-netbsd*
2298 OpenBSD/amd64 x86_64-*-openbsd*
2299 OpenBSD/alpha alpha*-*-openbsd*
2300 OpenBSD/sparc sparc-*-openbsd*
2301 OpenBSD/sparc64 sparc64-*-openbsd*
2303 * New debugging protocols
2305 M32R with SDI protocol m32r-*-elf*
2307 * "set prompt-escape-char" command deleted.
2309 The command "set prompt-escape-char" has been deleted. This command,
2310 and its very obscure effet on GDB's prompt, was never documented,
2311 tested, nor mentioned in the NEWS file.
2313 * OBSOLETE configurations and files
2315 Configurations that have been declared obsolete in this release have
2316 been commented out. Unless there is activity to revive these
2317 configurations, the next release of GDB will have their sources
2318 permanently REMOVED.
2320 Sun 3, running SunOS 3 m68*-*-sunos3*
2321 Sun 3, running SunOS 4 m68*-*-sunos4*
2322 Sun 2, running SunOS 3 m68000-*-sunos3*
2323 Sun 2, running SunOS 4 m68000-*-sunos4*
2324 Motorola 680x0 running LynxOS m68*-*-lynxos*
2325 AT&T 3b1/Unix pc m68*-att-*
2326 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2327 decstation mips-dec-* mips-little-*
2328 riscos mips-*-riscos* mips-*-sysv*
2329 sonymips mips-sony-*
2330 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2332 * REMOVED configurations and files
2334 SGI Irix-4.x mips-sgi-irix4 or iris4
2335 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2336 Z8000 simulator z8k-zilog-none or z8ksim
2337 Matsushita MN10200 w/simulator mn10200-*-*
2338 H8/500 simulator h8500-hitachi-hms or h8500hms
2339 HP/PA running BSD hppa*-*-bsd*
2340 HP/PA running OSF/1 hppa*-*-osf*
2341 HP/PA Pro target hppa*-*-pro*
2342 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2343 386BSD i[3456]86-*-bsd*
2344 Sequent family i[3456]86-sequent-sysv4*
2345 i[3456]86-sequent-sysv*
2346 i[3456]86-sequent-bsd*
2347 SPARC running LynxOS sparc-*-lynxos*
2348 SPARC running SunOS 4 sparc-*-sunos4*
2349 Tsqware Sparclet sparclet-*-*
2350 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2352 *** Changes in GDB 6.0:
2356 Support for debugging the Objective-C programming language has been
2357 integrated into GDB.
2359 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2361 DWARF 2's Call Frame Information makes available compiler generated
2362 information that more exactly describes the program's run-time stack.
2363 By using this information, GDB is able to provide more robust stack
2366 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2367 have been updated to use a new backtrace mechanism which includes
2368 DWARF 2 CFI support.
2372 GDB's remote protocol has been extended to include support for hosted
2373 file I/O (where the remote target uses GDB's file system). See GDB's
2374 remote protocol documentation for details.
2376 * All targets using the new architecture framework.
2378 All of GDB's targets have been updated to use the new internal
2379 architecture framework. The way is now open for future GDB releases
2380 to include cross-architecture native debugging support (i386 on amd64,
2383 * GNU/Linux's Thread Local Storage (TLS)
2385 GDB now includes support for for the GNU/Linux implementation of
2386 per-thread variables.
2388 * GNU/Linux's Native POSIX Thread Library (NPTL)
2390 GDB's thread code has been updated to work with either the new
2391 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2393 * Separate debug info.
2395 GDB, in conjunction with BINUTILS, now supports a mechanism for
2396 automatically loading debug information from a separate file. Instead
2397 of shipping full debug and non-debug versions of system libraries,
2398 system integrators can now instead ship just the stripped libraries
2399 and optional debug files.
2401 * DWARF 2 Location Expressions
2403 DWARF 2 Location Expressions allow the compiler to more completely
2404 describe the location of variables (even in optimized code) to the
2407 GDB now includes preliminary support for location expressions (support
2408 for DW_OP_piece is still missing).
2412 A number of long standing bugs that caused GDB to die while starting a
2413 Java application have been fixed. GDB's Java support is now
2414 considered "useable".
2416 * GNU/Linux support for fork, vfork, and exec.
2418 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2419 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2422 * GDB supports logging output to a file
2424 There are two new commands, "set logging" and "show logging", which can be
2425 used to capture GDB's output to a file.
2427 * The meaning of "detach" has changed for gdbserver
2429 The "detach" command will now resume the application, as documented. To
2430 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2433 * d10v, m68hc11 `regs' command deprecated
2435 The `info registers' command has been updated so that it displays the
2436 registers using a format identical to the old `regs' command.
2440 A new command, "maint set profile on/off", has been added. This command can
2441 be used to enable or disable profiling while running GDB, to profile a
2442 session or a set of commands. In addition there is a new configure switch,
2443 "--enable-profiling", which will cause GDB to be compiled with profiling
2444 data, for more informative profiling results.
2446 * Default MI syntax changed to "mi2".
2448 The default MI (machine interface) syntax, enabled by the command line
2449 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2450 "mi1", can be enabled by specifying the option "-i=mi1".
2452 Support for the original "mi0" syntax (included in GDB 5.0) has been
2455 Fix for gdb/192: removed extraneous space when displaying frame level.
2456 Fix for gdb/672: update changelist is now output in mi list format.
2457 Fix for gdb/702: a -var-assign that updates the value now shows up
2458 in a subsequent -var-update.
2460 * New native configurations.
2462 FreeBSD/amd64 x86_64-*-freebsd*
2464 * Multi-arched targets.
2466 HP/PA HPUX11 hppa*-*-hpux*
2467 Renesas M32R/D w/simulator m32r-*-elf*
2469 * OBSOLETE configurations and files
2471 Configurations that have been declared obsolete in this release have
2472 been commented out. Unless there is activity to revive these
2473 configurations, the next release of GDB will have their sources
2474 permanently REMOVED.
2476 Z8000 simulator z8k-zilog-none or z8ksim
2477 Matsushita MN10200 w/simulator mn10200-*-*
2478 H8/500 simulator h8500-hitachi-hms or h8500hms
2479 HP/PA running BSD hppa*-*-bsd*
2480 HP/PA running OSF/1 hppa*-*-osf*
2481 HP/PA Pro target hppa*-*-pro*
2482 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2483 Sequent family i[3456]86-sequent-sysv4*
2484 i[3456]86-sequent-sysv*
2485 i[3456]86-sequent-bsd*
2486 Tsqware Sparclet sparclet-*-*
2487 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2489 * REMOVED configurations and files
2492 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2493 IBM AIX PS/2 i[3456]86-*-aix
2494 i386 running Mach 3.0 i[3456]86-*-mach3*
2495 i386 running Mach i[3456]86-*-mach*
2496 i386 running OSF/1 i[3456]86-*osf1mk*
2497 HP/Apollo 68k Family m68*-apollo*-sysv*,
2499 m68*-hp-bsd*, m68*-hp-hpux*
2500 Argonaut Risc Chip (ARC) arc-*-*
2501 Mitsubishi D30V d30v-*-*
2502 Fujitsu FR30 fr30-*-elf*
2503 OS/9000 i[34]86-*-os9k
2504 I960 with MON960 i960-*-coff
2506 * MIPS $fp behavior changed
2508 The convenience variable $fp, for the MIPS, now consistently returns
2509 the address of the current frame's base. Previously, depending on the
2510 context, $fp could refer to either $sp or the current frame's base
2511 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2512 The GNU Source-Level Debugger''.
2514 *** Changes in GDB 5.3:
2516 * GNU/Linux shared library multi-threaded performance improved.
2518 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2519 `/proc', in preference to `ptrace' for memory reads. This may result
2520 in an improvement in the start-up time of multi-threaded, shared
2521 library applications when run under GDB. One GDB user writes: ``loads
2522 shared libs like mad''.
2524 * ``gdbserver'' now supports multi-threaded applications on some targets
2526 Support for debugging multi-threaded applications which use
2527 the GNU/Linux LinuxThreads package has been added for
2528 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2529 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2531 * GDB now supports C/C++ preprocessor macros.
2533 GDB now expands preprocessor macro invocations in C/C++ expressions,
2534 and provides various commands for showing macro definitions and how
2537 The new command `macro expand EXPRESSION' expands any macro
2538 invocations in expression, and shows the result.
2540 The new command `show macro MACRO-NAME' shows the definition of the
2541 macro named MACRO-NAME, and where it was defined.
2543 Most compilers don't include information about macros in the debugging
2544 information by default. In GCC 3.1, for example, you need to compile
2545 your program with the options `-gdwarf-2 -g3'. If the macro
2546 information is present in the executable, GDB will read it.
2548 * Multi-arched targets.
2550 DEC Alpha (partial) alpha*-*-*
2551 DEC VAX (partial) vax-*-*
2553 National Semiconductor NS32000 (partial) ns32k-*-*
2554 Motorola 68000 (partial) m68k-*-*
2555 Motorola MCORE mcore-*-*
2559 Fujitsu FRV architecture added by Red Hat frv*-*-*
2562 * New native configurations
2564 Alpha NetBSD alpha*-*-netbsd*
2565 SH NetBSD sh*-*-netbsdelf*
2566 MIPS NetBSD mips*-*-netbsd*
2567 UltraSPARC NetBSD sparc64-*-netbsd*
2569 * OBSOLETE configurations and files
2571 Configurations that have been declared obsolete in this release have
2572 been commented out. Unless there is activity to revive these
2573 configurations, the next release of GDB will have their sources
2574 permanently REMOVED.
2576 Mitsubishi D30V d30v-*-*
2577 OS/9000 i[34]86-*-os9k
2578 IBM AIX PS/2 i[3456]86-*-aix
2579 Fujitsu FR30 fr30-*-elf*
2580 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2581 Argonaut Risc Chip (ARC) arc-*-*
2582 i386 running Mach 3.0 i[3456]86-*-mach3*
2583 i386 running Mach i[3456]86-*-mach*
2584 i386 running OSF/1 i[3456]86-*osf1mk*
2585 HP/Apollo 68k Family m68*-apollo*-sysv*,
2587 m68*-hp-bsd*, m68*-hp-hpux*
2588 I960 with MON960 i960-*-coff
2590 * OBSOLETE languages
2592 CHILL, a Pascal like language used by telecommunications companies.
2594 * REMOVED configurations and files
2596 AMD 29k family via UDI a29k-amd-udi, udi29k
2597 A29K VxWorks a29k-*-vxworks
2598 AMD 29000 embedded, using EBMON a29k-none-none
2599 AMD 29000 embedded with COFF a29k-none-coff
2600 AMD 29000 embedded with a.out a29k-none-aout
2602 testsuite/gdb.hp/gdb.threads-hp/ directory
2604 * New command "set max-user-call-depth <nnn>"
2606 This command allows the user to limit the call depth of user-defined
2607 commands. The default is 1024.
2609 * Changes in FreeBSD/i386 native debugging.
2611 Support for the "generate-core-file" has been added.
2613 * New commands "dump", "append", and "restore".
2615 These commands allow data to be copied from target memory
2616 to a bfd-format or binary file (dump and append), and back
2617 from a file into memory (restore).
2619 * Improved "next/step" support on multi-processor Alpha Tru64.
2621 The previous single-step mechanism could cause unpredictable problems,
2622 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2623 of a software single-step mechanism prevents this.
2625 *** Changes in GDB 5.2.1:
2633 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2634 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2635 Fix, by Joel Brobecker imported from mainline.
2637 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2638 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2639 Fix, by Fred Fish, imported from mainline.
2641 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2642 Surprisingly enough, it works now.
2643 By Michal Ludvig, imported from mainline.
2645 i386 hardware watchpoint support:
2646 avoid misses on second run for some targets.
2647 By Pierre Muller, imported from mainline.
2649 *** Changes in GDB 5.2:
2651 * New command "set trust-readonly-sections on[off]".
2653 This command is a hint that tells gdb that read-only sections
2654 really are read-only (ie. that their contents will not change).
2655 In this mode, gdb will go to the object file rather than the
2656 target to read memory from read-only sections (such as ".text").
2657 This can be a significant performance improvement on some
2658 (notably embedded) targets.
2660 * New command "generate-core-file" (or "gcore").
2662 This new gdb command allows the user to drop a core file of the child
2663 process state at any time. So far it's been implemented only for
2664 GNU/Linux and Solaris, but should be relatively easily ported to other
2665 hosts. Argument is core file name (defaults to core.<pid>).
2667 * New command line option
2669 GDB now accepts --pid or -p followed by a process id.
2671 * Change in command line behavior -- corefiles vs. process ids.
2673 There is a subtle behavior in the way in which GDB handles
2674 command line arguments. The first non-flag argument is always
2675 a program to debug, but the second non-flag argument may either
2676 be a corefile or a process id. Previously, GDB would attempt to
2677 open the second argument as a corefile, and if that failed, would
2678 issue a superfluous error message and then attempt to attach it as
2679 a process. Now, if the second argument begins with a non-digit,
2680 it will be treated as a corefile. If it begins with a digit,
2681 GDB will attempt to attach it as a process, and if no such process
2682 is found, will then attempt to open it as a corefile.
2684 * Changes in ARM configurations.
2686 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2687 configuration is fully multi-arch.
2689 * New native configurations
2691 ARM NetBSD arm*-*-netbsd*
2692 x86 OpenBSD i[3456]86-*-openbsd*
2693 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2694 Sparc64 running FreeBSD sparc64-*-freebsd*
2698 Sanyo XStormy16 xstormy16-elf
2700 * OBSOLETE configurations and files
2702 Configurations that have been declared obsolete in this release have
2703 been commented out. Unless there is activity to revive these
2704 configurations, the next release of GDB will have their sources
2705 permanently REMOVED.
2707 AMD 29k family via UDI a29k-amd-udi, udi29k
2708 A29K VxWorks a29k-*-vxworks
2709 AMD 29000 embedded, using EBMON a29k-none-none
2710 AMD 29000 embedded with COFF a29k-none-coff
2711 AMD 29000 embedded with a.out a29k-none-aout
2713 testsuite/gdb.hp/gdb.threads-hp/ directory
2715 * REMOVED configurations and files
2717 TI TMS320C80 tic80-*-*
2719 PowerPC Solaris powerpcle-*-solaris*
2720 PowerPC Windows NT powerpcle-*-cygwin32
2721 PowerPC Netware powerpc-*-netware*
2722 Harris/CXUX m88k m88*-harris-cxux*
2723 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2724 ns32k-utek-sysv* ns32k-utek-*
2725 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2726 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2727 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2728 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2729 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2731 * Changes to command line processing
2733 The new `--args' feature can be used to specify command-line arguments
2734 for the inferior from gdb's command line.
2736 * Changes to key bindings
2738 There is a new `operate-and-get-next' function bound to `C-o'.
2740 *** Changes in GDB 5.1.1
2742 Fix compile problem on DJGPP.
2744 Fix a problem with floating-point registers on the i386 being
2747 Fix to stop GDB crashing on .debug_str debug info.
2749 Numerous documentation fixes.
2751 Numerous testsuite fixes.
2753 *** Changes in GDB 5.1:
2755 * New native configurations
2757 Alpha FreeBSD alpha*-*-freebsd*
2758 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2759 MIPS GNU/Linux mips*-*-linux*
2760 MIPS SGI Irix 6.x mips*-sgi-irix6*
2761 ia64 AIX ia64-*-aix*
2762 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2766 Motorola 68HC11 and 68HC12 m68hc11-elf
2768 UltraSparc running GNU/Linux sparc64-*-linux*
2770 * OBSOLETE configurations and files
2772 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2773 Harris/CXUX m88k m88*-harris-cxux*
2774 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2775 ns32k-utek-sysv* ns32k-utek-*
2776 TI TMS320C80 tic80-*-*
2778 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2779 PowerPC Solaris powerpcle-*-solaris*
2780 PowerPC Windows NT powerpcle-*-cygwin32
2781 PowerPC Netware powerpc-*-netware*
2782 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2783 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2784 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2785 Apple Macintosh (MPW) host N/A
2787 stuff.c (Program to stuff files into a specially prepared space in kdb)
2788 kdb-start.c (Main loop for the standalone kernel debugger)
2790 Configurations that have been declared obsolete in this release have
2791 been commented out. Unless there is activity to revive these
2792 configurations, the next release of GDB will have their sources
2793 permanently REMOVED.
2795 * REMOVED configurations and files
2797 Altos 3068 m68*-altos-*
2798 Convex c1-*-*, c2-*-*
2800 ARM RISCix arm-*-* (as host)
2804 * GDB has been converted to ISO C.
2806 GDB's source code has been converted to ISO C. In particular, the
2807 sources are fully protoized, and rely on standard headers being
2812 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2814 * The MI enabled by default.
2816 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2817 revised and enabled by default. Packages which use GDB as a debugging
2818 engine behind a UI or another front end are encouraged to switch to
2819 using the GDB/MI interface, instead of the old annotations interface
2820 which is now deprecated.
2822 * Support for debugging Pascal programs.
2824 GDB now includes support for debugging Pascal programs. The following
2825 main features are supported:
2827 - Pascal-specific data types such as sets;
2829 - automatic recognition of Pascal sources based on file-name
2832 - Pascal-style display of data types, variables, and functions;
2834 - a Pascal expression parser.
2836 However, some important features are not yet supported.
2838 - Pascal string operations are not supported at all;
2840 - there are some problems with boolean types;
2842 - Pascal type hexadecimal constants are not supported
2843 because they conflict with the internal variables format;
2845 - support for Pascal objects and classes is not full yet;
2847 - unlike Pascal, GDB is case-sensitive for symbol names.
2849 * Changes in completion.
2851 Commands such as `shell', `run' and `set args', which pass arguments
2852 to inferior programs, now complete on file names, similar to what
2853 users expect at the shell prompt.
2855 Commands which accept locations, such as `disassemble', `print',
2856 `breakpoint', `until', etc. now complete on filenames as well as
2857 program symbols. Thus, if you type "break foob TAB", and the source
2858 files linked into the programs include `foobar.c', that file name will
2859 be one of the candidates for completion. However, file names are not
2860 considered for completion after you typed a colon that delimits a file
2861 name from a name of a function in that file, as in "break foo.c:bar".
2863 `set demangle-style' completes on available demangling styles.
2865 * New platform-independent commands:
2867 It is now possible to define a post-hook for a command as well as a
2868 hook that runs before the command. For more details, see the
2869 documentation of `hookpost' in the GDB manual.
2871 * Changes in GNU/Linux native debugging.
2873 Support for debugging multi-threaded programs has been completely
2874 revised for all platforms except m68k and sparc. You can now debug as
2875 many threads as your system allows you to have.
2877 Attach/detach is supported for multi-threaded programs.
2879 Support for SSE registers was added for x86. This doesn't work for
2880 multi-threaded programs though.
2882 * Changes in MIPS configurations.
2884 Multi-arch support is enabled for all MIPS configurations.
2886 GDB can now be built as native debugger on SGI Irix 6.x systems for
2887 debugging n32 executables. (Debugging 64-bit executables is not yet
2890 * Unified support for hardware watchpoints in all x86 configurations.
2892 Most (if not all) native x86 configurations support hardware-assisted
2893 breakpoints and watchpoints in a unified manner. This support
2894 implements debug register sharing between watchpoints, which allows to
2895 put a virtually infinite number of watchpoints on the same address,
2896 and also supports watching regions up to 16 bytes with several debug
2899 The new maintenance command `maintenance show-debug-regs' toggles
2900 debugging print-outs in functions that insert, remove, and test
2901 watchpoints and hardware breakpoints.
2903 * Changes in the DJGPP native configuration.
2905 New command ``info dos sysinfo'' displays assorted information about
2906 the CPU, OS, memory, and DPMI server.
2908 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2909 display information about segment descriptors stored in GDT, LDT, and
2912 New commands ``info dos pde'' and ``info dos pte'' display entries
2913 from Page Directory and Page Tables (for now works with CWSDPMI only).
2914 New command ``info dos address-pte'' displays the Page Table entry for
2915 a given linear address.
2917 GDB can now pass command lines longer than 126 characters to the
2918 program being debugged (requires an update to the libdbg.a library
2919 which is part of the DJGPP development kit).
2921 DWARF2 debug info is now supported.
2923 It is now possible to `step' and `next' through calls to `longjmp'.
2925 * Changes in documentation.
2927 All GDB documentation was converted to GFDL, the GNU Free
2928 Documentation License.
2930 Tracepoints-related commands are now fully documented in the GDB
2933 TUI, the Text-mode User Interface, is now documented in the manual.
2935 Tracepoints-related commands are now fully documented in the GDB
2938 The "GDB Internals" manual now has an index. It also includes
2939 documentation of `ui_out' functions, GDB coding standards, x86
2940 hardware watchpoints, and memory region attributes.
2942 * GDB's version number moved to ``version.in''
2944 The Makefile variable VERSION has been replaced by the file
2945 ``version.in''. People creating GDB distributions should update the
2946 contents of this file.
2950 GUD support is now a standard part of the EMACS distribution.
2952 *** Changes in GDB 5.0:
2954 * Improved support for debugging FP programs on x86 targets
2956 Unified and much-improved support for debugging floating-point
2957 programs on all x86 targets. In particular, ``info float'' now
2958 displays the FP registers in the same format on all x86 targets, with
2959 greater level of detail.
2961 * Improvements and bugfixes in hardware-assisted watchpoints
2963 It is now possible to watch array elements, struct members, and
2964 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2965 on x86 targets no longer erroneously trigger when the address is
2968 * Improvements in the native DJGPP version of GDB
2970 The distribution now includes all the scripts and auxiliary files
2971 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2972 machines ``out of the box''.
2974 The DJGPP version can now debug programs that use signals. It is
2975 possible to catch signals that happened in the debuggee, deliver
2976 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2977 would kill the program being debugged.) Programs that hook hardware
2978 interrupts (keyboard, timer, etc.) can also be debugged.
2980 It is now possible to debug DJGPP programs that redirect their
2981 standard handles or switch them to raw (as opposed to cooked) mode, or
2982 even close them. The command ``run < foo > bar'' works as expected,
2983 and ``info terminal'' reports useful information about the debuggee's
2984 terminal, including raw/cooked mode, redirection, etc.
2986 The DJGPP version now uses termios functions for console I/O, which
2987 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2990 DOS-style file names with drive letters are now fully supported by
2993 It is now possible to debug DJGPP programs that switch their working
2994 directory. It is also possible to rerun the debuggee any number of
2995 times without restarting GDB; thus, you can use the same setup,
2996 breakpoints, etc. for many debugging sessions.
2998 * New native configurations
3000 ARM GNU/Linux arm*-*-linux*
3001 PowerPC GNU/Linux powerpc-*-linux*
3005 Motorola MCore mcore-*-*
3006 x86 VxWorks i[3456]86-*-vxworks*
3007 PowerPC VxWorks powerpc-*-vxworks*
3008 TI TMS320C80 tic80-*-*
3010 * OBSOLETE configurations
3012 Altos 3068 m68*-altos-*
3013 Convex c1-*-*, c2-*-*
3015 ARM RISCix arm-*-* (as host)
3018 Configurations that have been declared obsolete will be commented out,
3019 but the code will be left in place. If there is no activity to revive
3020 these configurations before the next release of GDB, the sources will
3021 be permanently REMOVED.
3023 * Gould support removed
3025 Support for the Gould PowerNode and NP1 has been removed.
3027 * New features for SVR4
3029 On SVR4 native platforms (such as Solaris), if you attach to a process
3030 without first loading a symbol file, GDB will now attempt to locate and
3031 load symbols from the running process's executable file.
3033 * Many C++ enhancements
3035 C++ support has been greatly improved. Overload resolution now works properly
3036 in almost all cases. RTTI support is on the way.
3038 * Remote targets can connect to a sub-program
3040 A popen(3) style serial-device has been added. This device starts a
3041 sub-process (such as a stand-alone simulator) and then communicates
3042 with that. The sub-program to run is specified using the syntax
3043 ``|<program> <args>'' vis:
3045 (gdb) set remotedebug 1
3046 (gdb) target extended-remote |mn10300-elf-sim program-args
3048 * MIPS 64 remote protocol
3050 A long standing bug in the mips64 remote protocol where by GDB
3051 expected certain 32 bit registers (ex SR) to be transfered as 32
3052 instead of 64 bits has been fixed.
3054 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3055 added to provide backward compatibility with older versions of GDB.
3057 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3059 The command ``set remotebinarydownload'' command has been replaced by
3060 ``set remote X-packet''. Other commands in ``set remote'' family
3061 include ``set remote P-packet''.
3063 * Breakpoint commands accept ranges.
3065 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3066 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3067 ``tracepoint passcount'' also accepts a range of tracepoints.
3069 * ``apropos'' command added.
3071 The ``apropos'' command searches through command names and
3072 documentation strings, printing out matches, making it much easier to
3073 try to find a command that does what you are looking for.
3077 A new machine oriented interface (MI) has been added to GDB. This
3078 interface is designed for debug environments running GDB as a separate
3079 process. This is part of the long term libGDB project. See the
3080 "GDB/MI" chapter of the GDB manual for further information. It can be
3081 enabled by configuring with:
3083 .../configure --enable-gdbmi
3085 *** Changes in GDB-4.18:
3087 * New native configurations
3089 HP-UX 10.20 hppa*-*-hpux10.20
3090 HP-UX 11.x hppa*-*-hpux11.0*
3091 M68K GNU/Linux m68*-*-linux*
3095 Fujitsu FR30 fr30-*-elf*
3096 Intel StrongARM strongarm-*-*
3097 Mitsubishi D30V d30v-*-*
3099 * OBSOLETE configurations
3101 Gould PowerNode, NP1 np1-*-*, pn-*-*
3103 Configurations that have been declared obsolete will be commented out,
3104 but the code will be left in place. If there is no activity to revive
3105 these configurations before the next release of GDB, the sources will
3106 be permanently REMOVED.
3110 As a compatibility experiment, GDB's source files buildsym.h and
3111 buildsym.c have been converted to pure standard C, no longer
3112 containing any K&R compatibility code. We believe that all systems in
3113 use today either come with a standard C compiler, or have a GCC port
3114 available. If this is not true, please report the affected
3115 configuration to bug-gdb@gnu.org immediately. See the README file for
3116 information about getting a standard C compiler if you don't have one
3121 GDB now uses readline 2.2.
3123 * set extension-language
3125 You can now control the mapping between filename extensions and source
3126 languages by using the `set extension-language' command. For instance,
3127 you can ask GDB to treat .c files as C++ by saying
3128 set extension-language .c c++
3129 The command `info extensions' lists all of the recognized extensions
3130 and their associated languages.
3132 * Setting processor type for PowerPC and RS/6000
3134 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3135 you can use the `set processor' command to specify what variant of the
3136 PowerPC family you are debugging. The command
3140 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3141 following PowerPC and RS6000 variants:
3143 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3144 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3146 403GC IBM PowerPC 403GC
3147 505 Motorola PowerPC 505
3148 860 Motorola PowerPC 860 or 850
3149 601 Motorola PowerPC 601
3150 602 Motorola PowerPC 602
3151 603 Motorola/IBM PowerPC 603 or 603e
3152 604 Motorola PowerPC 604 or 604e
3153 750 Motorola/IBM PowerPC 750 or 750
3155 At the moment, this command just tells GDB what to name the
3156 special-purpose processor registers. Since almost all the affected
3157 registers are inaccessible to user-level programs, this command is
3158 only useful for remote debugging in its present form.
3162 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3163 more extensive support for HP-UX. Added features include shared
3164 library support, kernel threads and hardware watchpoints for 11.00,
3165 support for HP's ANSI C and C++ compilers, and a compatibility mode
3166 for xdb and dbx commands.
3170 HP's donation includes the new concept of catchpoints, which is a
3171 generalization of the old catch command. On HP-UX, it is now possible
3172 to catch exec, fork, and vfork, as well as library loading.
3174 This means that the existing catch command has changed; its first
3175 argument now specifies the type of catch to be set up. See the
3176 output of "help catch" for a list of catchpoint types.
3178 * Debugging across forks
3180 On HP-UX, you can choose which process to debug when a fork() happens
3185 HP has donated a curses-based terminal user interface (TUI). To get
3186 it, build with --enable-tui. Although this can be enabled for any
3187 configuration, at present it only works for native HP debugging.
3189 * GDB remote protocol additions
3191 A new protocol packet 'X' that writes binary data is now available.
3192 Default behavior is to try 'X', then drop back to 'M' if the stub
3193 fails to respond. The settable variable `remotebinarydownload'
3194 allows explicit control over the use of 'X'.
3196 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3197 full 64-bit address. The command
3199 set remoteaddresssize 32
3201 can be used to revert to the old behaviour. For existing remote stubs
3202 the change should not be noticed, as the additional address information
3205 In order to assist in debugging stubs, you may use the maintenance
3206 command `packet' to send any text string to the stub. For instance,
3208 maint packet heythere
3210 sends the packet "$heythere#<checksum>". Note that it is very easy to
3211 disrupt a debugging session by sending the wrong packet at the wrong
3214 The compare-sections command allows you to compare section data on the
3215 target to what is in the executable file without uploading or
3216 downloading, by comparing CRC checksums.
3218 * Tracing can collect general expressions
3220 You may now collect general expressions at tracepoints. This requires
3221 further additions to the target-side stub; see tracepoint.c and
3222 doc/agentexpr.texi for further details.
3224 * mask-address variable for Mips
3226 For Mips targets, you may control the zeroing of the upper 32 bits of
3227 a 64-bit address by entering `set mask-address on'. This is mainly
3228 of interest to users of embedded R4xxx and R5xxx processors.
3230 * Higher serial baud rates
3232 GDB's serial code now allows you to specify baud rates 57600, 115200,
3233 230400, and 460800 baud. (Note that your host system may not be able
3234 to achieve all of these rates.)
3238 The i960 configuration now includes an initial implementation of a
3239 builtin simulator, contributed by Jim Wilson.
3242 *** Changes in GDB-4.17:
3244 * New native configurations
3246 Alpha GNU/Linux alpha*-*-linux*
3247 Unixware 2.x i[3456]86-unixware2*
3248 Irix 6.x mips*-sgi-irix6*
3249 PowerPC GNU/Linux powerpc-*-linux*
3250 PowerPC Solaris powerpcle-*-solaris*
3251 Sparc GNU/Linux sparc-*-linux*
3252 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3256 Argonaut Risc Chip (ARC) arc-*-*
3257 Hitachi H8/300S h8300*-*-*
3258 Matsushita MN10200 w/simulator mn10200-*-*
3259 Matsushita MN10300 w/simulator mn10300-*-*
3260 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3261 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3262 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3263 Mitsubishi D10V w/simulator d10v-*-*
3264 Mitsubishi M32R/D w/simulator m32r-*-elf*
3265 Tsqware Sparclet sparclet-*-*
3266 NEC V850 w/simulator v850-*-*
3268 * New debugging protocols
3270 ARM with RDI protocol arm*-*-*
3271 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3272 DDB and LSI variants of PMON protocol mips*-*-*
3273 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3274 PowerPC with SDS protocol powerpc{,le}-*-eabi
3275 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3279 All configurations can now understand and use the DWARF 2 debugging
3280 format. The choice is automatic, if the symbol file contains DWARF 2
3285 GDB now includes basic Java language support. This support is
3286 only useful with Java compilers that produce native machine code.
3288 * solib-absolute-prefix and solib-search-path
3290 For SunOS and SVR4 shared libraries, you may now set the prefix for
3291 loading absolute shared library symbol files, and the search path for
3292 locating non-absolute shared library symbol files.
3294 * Live range splitting
3296 GDB can now effectively debug code for which GCC has performed live
3297 range splitting as part of its optimization. See gdb/doc/LRS for
3298 more details on the expected format of the stabs information.
3302 GDB's support for the GNU Hurd, including thread debugging, has been
3303 updated to work with current versions of the Hurd.
3307 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3308 instruction set. ARM GDB automatically detects when Thumb
3309 instructions are in use, and adjusts disassembly and backtracing
3314 GDB's MIPS target configurations now handle the MIP16 16-bit
3319 GDB now includes support for overlays; if an executable has been
3320 linked such that multiple sections are based at the same address, GDB
3321 will decide which section to use for symbolic info. You can choose to
3322 control the decision manually, using overlay commands, or implement
3323 additional target-side support and use "overlay load-target" to bring
3324 in the overlay mapping. Do "help overlay" for more detail.
3328 The command "info symbol <address>" displays information about
3329 the symbol at the specified address.
3333 The standard remote protocol now includes an extension that allows
3334 asynchronous collection and display of trace data. This requires
3335 extensive support in the target-side debugging stub. Tracing mode
3336 includes a new interaction mode in GDB and new commands: see the
3337 file tracepoint.c for more details.
3341 Configurations for embedded MIPS now include a simulator contributed
3342 by Cygnus Solutions. The simulator supports the instruction sets
3343 of most MIPS variants.
3347 Sparc configurations may now include the ERC32 simulator contributed
3348 by the European Space Agency. The simulator is not built into
3349 Sparc targets by default; configure with --enable-sim to include it.
3353 For target configurations that may include multiple variants of a
3354 basic architecture (such as MIPS and SH), you may now set the
3355 architecture explicitly. "set arch" sets, "info arch" lists
3356 the possible architectures.
3358 *** Changes in GDB-4.16:
3360 * New native configurations
3362 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3363 M68K NetBSD m68k-*-netbsd*
3364 PowerPC AIX 4.x powerpc-*-aix*
3365 PowerPC MacOS powerpc-*-macos*
3366 PowerPC Windows NT powerpcle-*-cygwin32
3367 RS/6000 AIX 4.x rs6000-*-aix4*
3371 ARM with RDP protocol arm-*-*
3372 I960 with MON960 i960-*-coff
3373 MIPS VxWorks mips*-*-vxworks*
3374 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3375 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3377 Matra Sparclet sparclet-*-*
3381 The powerpc-eabi configuration now includes the PSIM simulator,
3382 contributed by Andrew Cagney, with assistance from Mike Meissner.
3383 PSIM is a very elaborate model of the PowerPC, including not only
3384 basic instruction set execution, but also details of execution unit
3385 performance and I/O hardware. See sim/ppc/README for more details.
3389 GDB now works with Solaris 2.5.
3391 * Windows 95/NT native
3393 GDB will now work as a native debugger on Windows 95 and Windows NT.
3394 To build it from source, you must use the "gnu-win32" environment,
3395 which uses a DLL to emulate enough of Unix to run the GNU tools.
3396 Further information, binaries, and sources are available at
3397 ftp.cygnus.com, under pub/gnu-win32.
3399 * dont-repeat command
3401 If a user-defined command includes the command `dont-repeat', then the
3402 command will not be repeated if the user just types return. This is
3403 useful if the command is time-consuming to run, so that accidental
3404 extra keystrokes don't run the same command many times.
3406 * Send break instead of ^C
3408 The standard remote protocol now includes an option to send a break
3409 rather than a ^C to the target in order to interrupt it. By default,
3410 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3412 * Remote protocol timeout
3414 The standard remote protocol includes a new variable `remotetimeout'
3415 that allows you to set the number of seconds before GDB gives up trying
3416 to read from the target. The default value is 2.
3418 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3420 By default GDB will automatically keep track of objects as they are
3421 loaded and unloaded by the dynamic linker. By using the command `set
3422 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3423 when shared library events occur, thus allowing you to set breakpoints
3424 in shared libraries which are explicitly loaded by the inferior.
3426 Note this feature does not work on hpux8. On hpux9 you must link
3427 /usr/lib/end.o into your program. This feature should work
3428 automatically on hpux10.
3430 * Irix 5.x hardware watchpoint support
3432 Irix 5 configurations now support the use of hardware watchpoints.
3434 * Mips protocol "SYN garbage limit"
3436 When debugging a Mips target using the `target mips' protocol, you
3437 may set the number of characters that GDB will ignore by setting
3438 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3439 every character. The default value is 1050.
3441 * Recording and replaying remote debug sessions
3443 If you set `remotelogfile' to the name of a file, gdb will write to it
3444 a recording of a remote debug session. This recording may then be
3445 replayed back to gdb using "gdbreplay". See gdbserver/README for
3446 details. This is useful when you have a problem with GDB while doing
3447 remote debugging; you can make a recording of the session and send it
3448 to someone else, who can then recreate the problem.
3450 * Speedups for remote debugging
3452 GDB includes speedups for downloading and stepping MIPS systems using
3453 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3454 and more efficient S-record downloading.
3456 * Memory use reductions and statistics collection
3458 GDB now uses less memory and reports statistics about memory usage.
3459 Try the `maint print statistics' command, for example.
3461 *** Changes in GDB-4.15:
3463 * Psymtabs for XCOFF
3465 The symbol reader for AIX GDB now uses partial symbol tables. This
3466 can greatly improve startup time, especially for large executables.
3468 * Remote targets use caching
3470 Remote targets now use a data cache to speed up communication with the
3471 remote side. The data cache could lead to incorrect results because
3472 it doesn't know about volatile variables, thus making it impossible to
3473 debug targets which use memory mapped I/O devices. `set remotecache
3474 off' turns the the data cache off.
3476 * Remote targets may have threads
3478 The standard remote protocol now includes support for multiple threads
3479 in the target system, using new protocol commands 'H' and 'T'. See
3480 gdb/remote.c for details.
3484 If GDB is configured with `--enable-netrom', then it will include
3485 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3486 acts as though it is a bank of ROM on the target board, but you can
3487 write into it over the network. GDB's support consists only of
3488 support for fast loading into the emulated ROM; to debug, you must use
3489 another protocol, such as standard remote protocol. The usual
3490 sequence is something like
3492 target nrom <netrom-hostname>
3494 target remote <netrom-hostname>:1235
3498 GDB now includes support for the Apple Macintosh, as a host only. It
3499 may be run as either an MPW tool or as a standalone application, and
3500 it can debug through the serial port. All the usual GDB commands are
3501 available, but to the target command, you must supply "serial" as the
3502 device type instead of "/dev/ttyXX". See mpw-README in the main
3503 directory for more information on how to build. The MPW configuration
3504 scripts */mpw-config.in support only a few targets, and only the
3505 mips-idt-ecoff target has been tested.
3509 GDB configuration now uses autoconf. This is not user-visible,
3510 but does simplify configuration and building.
3514 GDB now supports hpux10.
3516 *** Changes in GDB-4.14:
3518 * New native configurations
3520 x86 FreeBSD i[345]86-*-freebsd
3521 x86 NetBSD i[345]86-*-netbsd
3522 NS32k NetBSD ns32k-*-netbsd
3523 Sparc NetBSD sparc-*-netbsd
3527 A29K VxWorks a29k-*-vxworks
3528 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3529 CPU32 EST-300 emulator m68*-*-est*
3530 PowerPC ELF powerpc-*-elf
3533 * Alpha OSF/1 support for procfs
3535 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3536 possible to attach to running processes. As the mounting of the /proc
3537 filesystem is optional on the Alpha, GDB automatically determines
3538 the availability of /proc during startup. This can lead to problems
3539 if /proc is unmounted after GDB has been started.
3541 * Arguments to user-defined commands
3543 User commands may accept up to 10 arguments separated by whitespace.
3544 Arguments are accessed within the user command via $arg0..$arg9. A
3547 print $arg0 + $arg1 + $arg2
3549 To execute the command use:
3552 Defines the command "adder" which prints the sum of its three arguments.
3553 Note the arguments are text substitutions, so they may reference variables,
3554 use complex expressions, or even perform inferior function calls.
3556 * New `if' and `while' commands
3558 This makes it possible to write more sophisticated user-defined
3559 commands. Both commands take a single argument, which is the
3560 expression to evaluate, and must be followed by the commands to
3561 execute, one per line, if the expression is nonzero, the list being
3562 terminated by the word `end'. The `if' command list may include an
3563 `else' word, which causes the following commands to be executed only
3564 if the expression is zero.
3566 * Fortran source language mode
3568 GDB now includes partial support for Fortran 77. It will recognize
3569 Fortran programs and can evaluate a subset of Fortran expressions, but
3570 variables and functions may not be handled correctly. GDB will work
3571 with G77, but does not yet know much about symbols emitted by other
3574 * Better HPUX support
3576 Most debugging facilities now work on dynamic executables for HPPAs
3577 running hpux9 or later. You can attach to running dynamically linked
3578 processes, but by default the dynamic libraries will be read-only, so
3579 for instance you won't be able to put breakpoints in them. To change
3580 that behavior do the following before running the program:
3586 This will cause the libraries to be mapped private and read-write.
3587 To revert to the normal behavior, do this:
3593 You cannot set breakpoints or examine data in the library until after
3594 the library is loaded if the function/data symbols do not have
3597 GDB can now also read debug symbols produced by the HP C compiler on
3598 HPPAs (sorry, no C++, Fortran or 68k support).
3600 * Target byte order now dynamically selectable
3602 You can choose which byte order to use with a target system, via the
3603 commands "set endian big" and "set endian little", and you can see the
3604 current setting by using "show endian". You can also give the command
3605 "set endian auto", in which case GDB will use the byte order
3606 associated with the executable. Currently, only embedded MIPS
3607 configurations support dynamic selection of target byte order.
3609 * New DOS host serial code
3611 This version uses DPMI interrupts to handle buffered I/O, so you
3612 no longer need to run asynctsr when debugging boards connected to
3615 *** Changes in GDB-4.13:
3617 * New "complete" command
3619 This lists all the possible completions for the rest of the line, if it
3620 were to be given as a command itself. This is intended for use by emacs.
3622 * Trailing space optional in prompt
3624 "set prompt" no longer adds a space for you after the prompt you set. This
3625 allows you to set a prompt which ends in a space or one that does not.
3627 * Breakpoint hit counts
3629 "info break" now displays a count of the number of times the breakpoint
3630 has been hit. This is especially useful in conjunction with "ignore"; you
3631 can ignore a large number of breakpoint hits, look at the breakpoint info
3632 to see how many times the breakpoint was hit, then run again, ignoring one
3633 less than that number, and this will get you quickly to the last hit of
3636 * Ability to stop printing at NULL character
3638 "set print null-stop" will cause GDB to stop printing the characters of
3639 an array when the first NULL is encountered. This is useful when large
3640 arrays actually contain only short strings.
3642 * Shared library breakpoints
3644 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3645 breakpoints in shared libraries before the executable is run.
3647 * Hardware watchpoints
3649 There is a new hardware breakpoint for the watch command for sparclite
3650 targets. See gdb/sparclite/hw_breakpoint.note.
3652 Hardware watchpoints are also now supported under GNU/Linux.
3656 Annotations have been added. These are for use with graphical interfaces,
3657 and are still experimental. Currently only gdba.el uses these.
3659 * Improved Irix 5 support
3661 GDB now works properly with Irix 5.2.
3663 * Improved HPPA support
3665 GDB now works properly with the latest GCC and GAS.
3667 * New native configurations
3669 Sequent PTX4 i[34]86-sequent-ptx4
3670 HPPA running OSF/1 hppa*-*-osf*
3671 Atari TT running SVR4 m68*-*-sysv4*
3672 RS/6000 LynxOS rs6000-*-lynxos*
3676 OS/9000 i[34]86-*-os9k
3677 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3680 * Hitachi SH7000 and E7000-PC ICE support
3682 There is now support for communicating with the Hitachi E7000-PC ICE.
3683 This is available automatically when GDB is configured for the SH.
3687 As usual, a variety of small fixes and improvements, both generic
3688 and configuration-specific. See the ChangeLog for more detail.
3690 *** Changes in GDB-4.12:
3692 * Irix 5 is now supported
3696 GDB-4.12 on the HPPA has a number of changes which make it unable
3697 to debug the output from the currently released versions of GCC and
3698 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3699 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3700 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3703 *** Changes in GDB-4.11:
3705 * User visible changes:
3709 The "set remotedebug" option is now consistent between the mips remote
3710 target, remote targets using the gdb-specific protocol, UDI (AMD's
3711 debug protocol for the 29k) and the 88k bug monitor. It is now an
3712 integer specifying a debug level (normally 0 or 1, but 2 means more
3713 debugging info for the mips target).
3715 * DEC Alpha native support
3717 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3718 debug info, but GDB works fairly well with the DEC compiler and should
3719 work with a future GCC release. See the README file for a few
3720 Alpha-specific notes.
3722 * Preliminary thread implementation
3724 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3726 * LynxOS native and target support for 386
3728 This release has been hosted on LynxOS 2.2, and also can be configured
3729 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3732 * Improvements in C++ mangling/demangling.
3734 This release has much better g++ debugging, specifically in name
3735 mangling/demangling, virtual function calls, print virtual table,
3736 call methods, ...etc.
3738 *** Changes in GDB-4.10:
3740 * User visible changes:
3742 Remote debugging using the GDB-specific (`target remote') protocol now
3743 supports the `load' command. This is only useful if you have some
3744 other way of getting the stub to the target system, and you can put it
3745 somewhere in memory where it won't get clobbered by the download.
3747 Filename completion now works.
3749 When run under emacs mode, the "info line" command now causes the
3750 arrow to point to the line specified. Also, "info line" prints
3751 addresses in symbolic form (as well as hex).
3753 All vxworks based targets now support a user settable option, called
3754 vxworks-timeout. This option represents the number of seconds gdb
3755 should wait for responses to rpc's. You might want to use this if
3756 your vxworks target is, perhaps, a slow software simulator or happens
3757 to be on the far side of a thin network line.
3761 This release contains support for using a DEC alpha as a GDB host for
3762 cross debugging. Native alpha debugging is not supported yet.
3765 *** Changes in GDB-4.9:
3769 This is the first GDB release which is accompanied by a matching testsuite.
3770 The testsuite requires installation of dejagnu, which should be available
3771 via ftp from most sites that carry GNU software.
3775 'Cfront' style demangling has had its name changed to 'ARM' style, to
3776 emphasize that it was written from the specifications in the C++ Annotated
3777 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3778 disclaimers, it still generated too much confusion with users attempting to
3779 use gdb with AT&T cfront.
3783 GDB now uses a standard remote interface to a simulator library.
3784 So far, the library contains simulators for the Zilog Z8001/2, the
3785 Hitachi H8/300, H8/500 and Super-H.
3787 * New targets supported
3789 H8/300 simulator h8300-hitachi-hms or h8300hms
3790 H8/500 simulator h8500-hitachi-hms or h8500hms
3791 SH simulator sh-hitachi-hms or sh
3792 Z8000 simulator z8k-zilog-none or z8ksim
3793 IDT MIPS board over serial line mips-idt-ecoff
3795 Cross-debugging to GO32 targets is supported. It requires a custom
3796 version of the i386-stub.c module which is integrated with the
3797 GO32 memory extender.
3799 * New remote protocols
3801 MIPS remote debugging protocol.
3803 * New source languages supported
3805 This version includes preliminary support for Chill, a Pascal like language
3806 used by telecommunications companies. Chill support is also being integrated
3807 into the GNU compiler, but we don't know when it will be publically available.
3810 *** Changes in GDB-4.8:
3812 * HP Precision Architecture supported
3814 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3815 version of this support was available as a set of patches from the
3816 University of Utah. GDB does not support debugging of programs
3817 compiled with the HP compiler, because HP will not document their file
3818 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3819 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3821 Many problems in the preliminary version have been fixed.
3823 * Faster and better demangling
3825 We have improved template demangling and fixed numerous bugs in the GNU style
3826 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3827 character types (wchar_t) are now supported. Demangling of each symbol is now
3828 only done once, and is cached when the symbol table for a file is read in.
3829 This results in a small increase in memory usage for C programs, a moderate
3830 increase in memory usage for C++ programs, and a fantastic speedup in
3833 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3834 from the specifications in the Annotated Reference Manual, which AT&T's
3835 compiler does not actually implement.
3837 * G++ multiple inheritance compiler problem
3839 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3840 inheritance lattices was reworked to properly discover ambiguities. We
3841 recently found an example which causes this new algorithm to fail in a
3842 very subtle way, producing bad debug information for those classes.
3843 The file 'gcc.patch' (in this directory) can be applied to gcc to
3844 circumvent the problem. A future GCC release will contain a complete
3847 The previous G++ debug info problem (mentioned below for the gdb-4.7
3848 release) is fixed in gcc version 2.3.2.
3850 * Improved configure script
3852 The `configure' script will now attempt to guess your system type if
3853 you don't supply a host system type. The old scheme of supplying a
3854 host system triplet is preferable over using this. All the magic is
3855 done in the new `config.guess' script. Examine it for details.
3857 We have also brought our configure script much more in line with the FSF's
3858 version. It now supports the --with-xxx options. In particular,
3859 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3860 The resulting GDB will not be able to read arbitrary object file formats --
3861 only the format ``expected'' to be used on the configured target system.
3862 We hope to make this the default in a future release.
3864 * Documentation improvements
3866 There's new internal documentation on how to modify GDB, and how to
3867 produce clean changes to the code. We implore people to read it
3868 before submitting changes.
3870 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3871 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3872 `info' files are also provided. To build `info' files from scratch,
3873 you will need the latest `makeinfo' release, which will be available in
3874 a future texinfo-X.Y release.
3876 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3877 We're not sure exactly which versions have this problem, but it has
3878 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3879 or better. If that isn't possible, there is a patch in
3880 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3881 around this problem.
3885 GDB now supports array constants that can be used in expressions typed in by
3886 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3887 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3890 The new directory `gdb/sparclite' contains a program that demonstrates
3891 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3893 * New native hosts supported
3895 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3896 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3898 * New targets supported
3900 AMD 29k family via UDI a29k-amd-udi or udi29k
3902 * New file formats supported
3904 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3905 HPUX core files, and SCO 3.2v2 core files.
3909 Attaching to processes now works again; thanks for the many bug reports.
3911 We have also stomped on a bunch of core dumps caused by
3912 printf_filtered("%s") problems.
3914 We eliminated a copyright problem on the rpc and ptrace header files
3915 for VxWorks, which was discovered at the last minute during the 4.7
3916 release. You should now be able to build a VxWorks GDB.
3918 You can now interrupt gdb while an attached process is running. This
3919 will cause the attached process to stop, and give control back to GDB.
3921 We fixed problems caused by using too many file descriptors
3922 for reading symbols from object files and libraries. This was
3923 especially a problem for programs that used many (~100) shared
3926 The `step' command now only enters a subroutine if there is line number
3927 information for the subroutine. Otherwise it acts like the `next'
3928 command. Previously, `step' would enter subroutines if there was
3929 any debugging information about the routine. This avoids problems
3930 when using `cc -g1' on MIPS machines.
3932 * Internal improvements
3934 GDB's internal interfaces have been improved to make it easier to support
3935 debugging of multiple languages in the future.
3937 GDB now uses a common structure for symbol information internally.
3938 Minimal symbols (derived from linkage symbols in object files), partial
3939 symbols (from a quick scan of debug information), and full symbols
3940 contain a common subset of information, making it easier to write
3941 shared code that handles any of them.
3943 * New command line options
3945 We now accept --silent as an alias for --quiet.
3949 The memory-mapped-malloc library is now licensed under the GNU Library
3950 General Public License.
3952 *** Changes in GDB-4.7:
3954 * Host/native/target split
3956 GDB has had some major internal surgery to untangle the support for
3957 hosts and remote targets. Now, when you configure GDB for a remote
3958 target, it will no longer load in all of the support for debugging
3959 local programs on the host. When fully completed and tested, this will
3960 ensure that arbitrary host/target combinations are possible.
3962 The primary conceptual shift is to separate the non-portable code in
3963 GDB into three categories. Host specific code is required any time GDB
3964 is compiled on that host, regardless of the target. Target specific
3965 code relates to the peculiarities of the target, but can be compiled on
3966 any host. Native specific code is everything else: it can only be
3967 built when the host and target are the same system. Child process
3968 handling and core file support are two common `native' examples.
3970 GDB's use of /proc for controlling Unix child processes is now cleaner.
3971 It has been split out into a single module under the `target_ops' vector,
3972 plus two native-dependent functions for each system that uses /proc.
3974 * New hosts supported
3976 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3977 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3978 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3980 * New targets supported
3982 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3983 68030 and CPU32 m68030-*-*, m68332-*-*
3985 * New native hosts supported
3987 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3988 (386bsd is not well tested yet)
3989 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3991 * New file formats supported
3993 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3994 supports reading of `a.out.adobe' object files, which are an a.out
3995 format extended with minimal information about multiple sections.
3999 `show copying' is the same as the old `info copying'.
4000 `show warranty' is the same as `info warrantee'.
4001 These were renamed for consistency. The old commands continue to work.
4003 `info handle' is a new alias for `info signals'.
4005 You can now define pre-command hooks, which attach arbitrary command
4006 scripts to any command. The commands in the hook will be executed
4007 prior to the user's command. You can also create a hook which will be
4008 executed whenever the program stops. See gdb.texinfo.
4012 We now deal with Cfront style name mangling, and can even extract type
4013 info from mangled symbols. GDB can automatically figure out which
4014 symbol mangling style your C++ compiler uses.
4016 Calling of methods and virtual functions has been improved as well.
4020 The crash that occured when debugging Sun Ansi-C compiled binaries is
4021 fixed. This was due to mishandling of the extra N_SO stabs output
4024 We also finally got Ultrix 4.2 running in house, and fixed core file
4025 support, with help from a dozen people on the net.
4027 John M. Farrell discovered that the reason that single-stepping was so
4028 slow on all of the Mips based platforms (primarily SGI and DEC) was
4029 that we were trying to demangle and lookup a symbol used for internal
4030 purposes on every instruction that was being stepped through. Changing
4031 the name of that symbol so that it couldn't be mistaken for a C++
4032 mangled symbol sped things up a great deal.
4034 Rich Pixley sped up symbol lookups in general by getting much smarter
4035 about when C++ symbol mangling is necessary. This should make symbol
4036 completion (TAB on the command line) much faster. It's not as fast as
4037 we'd like, but it's significantly faster than gdb-4.6.
4041 A new user controllable variable 'call_scratch_address' can
4042 specify the location of a scratch area to be used when GDB
4043 calls a function in the target. This is necessary because the
4044 usual method of putting the scratch area on the stack does not work
4045 in systems that have separate instruction and data spaces.
4047 We integrated changes to support the 29k UDI (Universal Debugger
4048 Interface), but discovered at the last minute that we didn't have all
4049 of the appropriate copyright paperwork. We are working with AMD to
4050 resolve this, and hope to have it available soon.
4054 We have sped up the remote serial line protocol, especially for targets
4055 with lots of registers. It now supports a new `expedited status' ('T')
4056 message which can be used in place of the existing 'S' status message.
4057 This allows the remote stub to send only the registers that GDB
4058 needs to make a quick decision about single-stepping or conditional
4059 breakpoints, eliminating the need to fetch the entire register set for
4060 each instruction being stepped through.
4062 The GDB remote serial protocol now implements a write-through cache for
4063 registers, only re-reading the registers if the target has run.
4065 There is also a new remote serial stub for SPARC processors. You can
4066 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4067 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4068 processor with a serial port.
4072 Configure.in files have become much easier to read and modify. A new
4073 `table driven' format makes it more obvious what configurations are
4074 supported, and what files each one uses.
4078 There is a new opcodes library which will eventually contain all of the
4079 disassembly routines and opcode tables. At present, it only contains
4080 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4081 disassembler (binutils/objdump) to share these routines.
4083 The libiberty library is now copylefted under the GNU Library General
4084 Public License. This allows more liberal use, and was done so libg++
4085 can use it. This makes no difference to GDB, since the Library License
4086 grants all the rights from the General Public License.
4090 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4091 reference to the stabs symbol info used by the debugger. It is (as far
4092 as we know) the only published document on this fascinating topic. We
4093 encourage you to read it, compare it to the stabs information on your
4094 system, and send improvements on the document in general (to
4095 bug-gdb@prep.ai.mit.edu).
4097 And, of course, many bugs have been fixed.
4100 *** Changes in GDB-4.6:
4102 * Better support for C++ function names
4104 GDB now accepts as input the "demangled form" of C++ overloaded function
4105 names and member function names, and can do command completion on such names
4106 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4107 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4108 Make use of command completion, it is your friend.
4110 GDB also now accepts a variety of C++ mangled symbol formats. They are
4111 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4112 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4113 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4114 for the list of formats.
4116 * G++ symbol mangling problem
4118 Recent versions of gcc have a bug in how they emit debugging information for
4119 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4120 directory) can be applied to gcc to fix the problem. Alternatively, if you
4121 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4122 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4123 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4126 * New 'maintenance' command
4128 All of the commands related to hacking GDB internals have been moved out of
4129 the main command set, and now live behind the 'maintenance' command. This
4130 can also be abbreviated as 'mt'. The following changes were made:
4132 dump-me -> maintenance dump-me
4133 info all-breakpoints -> maintenance info breakpoints
4134 printmsyms -> maintenance print msyms
4135 printobjfiles -> maintenance print objfiles
4136 printpsyms -> maintenance print psymbols
4137 printsyms -> maintenance print symbols
4139 The following commands are new:
4141 maintenance demangle Call internal GDB demangler routine to
4142 demangle a C++ link name and prints the result.
4143 maintenance print type Print a type chain for a given symbol
4145 * Change to .gdbinit file processing
4147 We now read the $HOME/.gdbinit file before processing the argv arguments
4148 (e.g. reading symbol files or core files). This allows global parameters to
4149 be set, which will apply during the symbol reading. The ./.gdbinit is still
4150 read after argv processing.
4152 * New hosts supported
4154 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4156 GNU/Linux support i386-unknown-linux or linux
4158 We are also including code to support the HP/PA running BSD and HPUX. This
4159 is almost guaranteed not to work, as we didn't have time to test or build it
4160 for this release. We are including it so that the more adventurous (or
4161 masochistic) of you can play with it. We also had major problems with the
4162 fact that the compiler that we got from HP doesn't support the -g option.
4165 * New targets supported
4167 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4169 * More smarts about finding #include files
4171 GDB now remembers the compilation directory for all include files, and for
4172 all files from which C is generated (like yacc and lex sources). This
4173 greatly improves GDB's ability to find yacc/lex sources, and include files,
4174 especially if you are debugging your program from a directory different from
4175 the one that contains your sources.
4177 We also fixed a bug which caused difficulty with listing and setting
4178 breakpoints in include files which contain C code. (In the past, you had to
4179 try twice in order to list an include file that you hadn't looked at before.)
4181 * Interesting infernals change
4183 GDB now deals with arbitrary numbers of sections, where the symbols for each
4184 section must be relocated relative to that section's landing place in the
4185 target's address space. This work was needed to support ELF with embedded
4186 stabs used by Solaris-2.0.
4188 * Bug fixes (of course!)
4190 There have been loads of fixes for the following things:
4191 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4192 i960, stabs, DOS(GO32), procfs, etc...
4194 See the ChangeLog for details.
4196 *** Changes in GDB-4.5:
4198 * New machines supported (host and target)
4200 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4202 SGI Irix-4.x mips-sgi-irix4 or iris4
4204 * New malloc package
4206 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4207 Mmalloc is capable of handling mutiple heaps of memory. It is also
4208 capable of saving a heap to a file, and then mapping it back in later.
4209 This can be used to greatly speedup the startup of GDB by using a
4210 pre-parsed symbol table which lives in a mmalloc managed heap. For
4211 more details, please read mmalloc/mmalloc.texi.
4215 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4216 'help info proc' for details.
4218 * MIPS ecoff symbol table format
4220 The code that reads MIPS symbol table format is now supported on all hosts.
4221 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4224 * File name changes for MS-DOS
4226 Many files in the config directories have been renamed to make it easier to
4227 support GDB on MS-DOSe systems (which have very restrictive file name
4228 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4229 environment) is close to working but has some remaining problems. Note
4230 that debugging of DOS programs is not supported, due to limitations
4231 in the ``operating system'', but it can be used to host cross-debugging.
4233 * Cross byte order fixes
4235 Many fixes have been made to support cross debugging of Sparc and MIPS
4236 targets from hosts whose byte order differs.
4238 * New -mapped and -readnow options
4240 If memory-mapped files are available on your system through the 'mmap'
4241 system call, you can use the -mapped option on the `file' or
4242 `symbol-file' commands to cause GDB to write the symbols from your
4243 program into a reusable file. If the program you are debugging is
4244 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4245 Future GDB debugging sessions will notice the presence of this file,
4246 and will quickly map in symbol information from it, rather than reading
4247 the symbol table from the executable program. Using the '-mapped'
4248 option in a GDB `file' or `symbol-file' command has the same effect as
4249 starting GDB with the '-mapped' command-line option.
4251 You can cause GDB to read the entire symbol table immediately by using
4252 the '-readnow' option with any of the commands that load symbol table
4253 information (or on the GDB command line). This makes the command
4254 slower, but makes future operations faster.
4256 The -mapped and -readnow options are typically combined in order to
4257 build a `fred.syms' file that contains complete symbol information.
4258 A simple GDB invocation to do nothing but build a `.syms' file for future
4261 gdb -batch -nx -mapped -readnow programname
4263 The `.syms' file is specific to the host machine on which GDB is run.
4264 It holds an exact image of GDB's internal symbol table. It cannot be
4265 shared across multiple host platforms.
4267 * longjmp() handling
4269 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4270 siglongjmp() without losing control. This feature has not yet been ported to
4271 all systems. It currently works on many 386 platforms, all MIPS-based
4272 platforms (SGI, DECstation, etc), and Sun3/4.
4276 Preliminary work has been put in to support the new Solaris OS from Sun. At
4277 this time, it can control and debug processes, but it is not capable of
4282 As always, many many bug fixes. The major areas were with g++, and mipsread.
4283 People using the MIPS-based platforms should experience fewer mysterious
4284 crashes and trashed symbol tables.
4286 *** Changes in GDB-4.4:
4288 * New machines supported (host and target)
4290 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4292 BSD Reno on Vax vax-dec-bsd
4293 Ultrix on Vax vax-dec-ultrix
4295 * New machines supported (target)
4297 AMD 29000 embedded, using EBMON a29k-none-none
4301 GDB continues to improve its handling of C++. `References' work better.
4302 The demangler has also been improved, and now deals with symbols mangled as
4303 per the Annotated C++ Reference Guide.
4305 GDB also now handles `stabs' symbol information embedded in MIPS
4306 `ecoff' symbol tables. Since the ecoff format was not easily
4307 extensible to handle new languages such as C++, this appeared to be a
4308 good way to put C++ debugging info into MIPS binaries. This option
4309 will be supported in the GNU C compiler, version 2, when it is
4312 * New features for SVR4
4314 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4315 shared libraries. Debugging dynamically linked programs should present
4316 only minor differences from debugging statically linked programs.
4318 The `info proc' command will print out information about any process
4319 on an SVR4 system (including the one you are debugging). At the moment,
4320 it prints the address mappings of the process.
4322 If you bring up GDB on another SVR4 system, please send mail to
4323 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4325 * Better dynamic linking support in SunOS
4327 Reading symbols from shared libraries which contain debugging symbols
4328 now works properly. However, there remain issues such as automatic
4329 skipping of `transfer vector' code during function calls, which
4330 make it harder to debug code in a shared library, than to debug the
4331 same code linked statically.
4335 GDB is now using the latest `getopt' routines from the FSF. This
4336 version accepts the -- prefix for options with long names. GDB will
4337 continue to accept the old forms (-option and +option) as well.
4338 Various single letter abbreviations for options have been explicity
4339 added to the option table so that they won't get overshadowed in the
4340 future by other options that begin with the same letter.
4344 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4345 Many assorted bugs have been handled. Many more remain to be handled.
4346 See the various ChangeLog files (primarily in gdb and bfd) for details.
4349 *** Changes in GDB-4.3:
4351 * New machines supported (host and target)
4353 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4354 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4355 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4357 * Almost SCO Unix support
4359 We had hoped to support:
4360 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4361 (except for core file support), but we discovered very late in the release
4362 that it has problems with process groups that render gdb unusable. Sorry
4363 about that. I encourage people to fix it and post the fixes.
4365 * Preliminary ELF and DWARF support
4367 GDB can read ELF object files on System V Release 4, and can handle
4368 debugging records for C, in DWARF format, in ELF files. This support
4369 is preliminary. If you bring up GDB on another SVR4 system, please
4370 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4375 GDB now uses the latest `readline' library. One user-visible change
4376 is that two tabs will list possible command completions, which previously
4377 required typing M-? (meta-question mark, or ESC ?).
4381 The `stepi' bug that many of you noticed has been squashed.
4382 Many bugs in C++ have been handled. Many more remain to be handled.
4383 See the various ChangeLog files (primarily in gdb and bfd) for details.
4385 * State of the MIPS world (in case you wondered):
4387 GDB can understand the symbol tables emitted by the compilers
4388 supplied by most vendors of MIPS-based machines, including DEC. These
4389 symbol tables are in a format that essentially nobody else uses.
4391 Some versions of gcc come with an assembler post-processor called
4392 mips-tfile. This program is required if you want to do source-level
4393 debugging of gcc-compiled programs. I believe FSF does not ship
4394 mips-tfile with gcc version 1, but it will eventually come with gcc
4397 Debugging of g++ output remains a problem. g++ version 1.xx does not
4398 really support it at all. (If you're lucky, you should be able to get
4399 line numbers and stack traces to work, but no parameters or local
4400 variables.) With some work it should be possible to improve the
4403 When gcc version 2 is released, you will have somewhat better luck.
4404 However, even then you will get confusing results for inheritance and
4407 We will eventually provide full debugging of g++ output on
4408 DECstations. This will probably involve some kind of stabs-in-ecoff
4409 encapulation, but the details have not been worked out yet.
4412 *** Changes in GDB-4.2:
4414 * Improved configuration
4416 Only one copy of `configure' exists now, and it is not self-modifying.
4417 Porting BFD is simpler.
4421 The `step' and `next' commands now only stop at the first instruction
4422 of a source line. This prevents the multiple stops that used to occur
4423 in switch statements, for-loops, etc. `Step' continues to stop if a
4424 function that has debugging information is called within the line.
4428 Lots of small bugs fixed. More remain.
4430 * New host supported (not target)
4432 Intel 386 PC clone running Mach i386-none-mach
4435 *** Changes in GDB-4.1:
4437 * Multiple source language support
4439 GDB now has internal scaffolding to handle several source languages.
4440 It determines the type of each source file from its filename extension,
4441 and will switch expression parsing and number formatting to match the
4442 language of the function in the currently selected stack frame.
4443 You can also specifically set the language to be used, with
4444 `set language c' or `set language modula-2'.
4448 GDB now has preliminary support for the GNU Modula-2 compiler,
4449 currently under development at the State University of New York at
4450 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4451 continue through the fall of 1991 and into 1992.
4453 Other Modula-2 compilers are currently not supported, and attempting to
4454 debug programs compiled with them will likely result in an error as the
4455 symbol table is read. Feel free to work on it, though!
4457 There are hooks in GDB for strict type checking and range checking,
4458 in the `Modula-2 philosophy', but they do not currently work.
4462 GDB can now write to executable and core files (e.g. patch
4463 a variable's value). You must turn this switch on, specify
4464 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4465 by assigning a new value to a variable. Modifications take
4468 * Automatic SunOS shared library reading
4470 When you run your program, GDB automatically determines where its
4471 shared libraries (if any) have been loaded, and reads their symbols.
4472 The `share' command is no longer needed. This also works when
4473 examining core files.
4477 You can specify the number of lines that the `list' command shows.
4480 * New machines supported (host and target)
4482 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4483 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4484 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4486 * New hosts supported (not targets)
4488 IBM RT/PC: romp-ibm-aix or rtpc
4490 * New targets supported (not hosts)
4492 AMD 29000 embedded with COFF a29k-none-coff
4493 AMD 29000 embedded with a.out a29k-none-aout
4494 Ultracomputer remote kernel debug a29k-nyu-kern
4496 * New remote interfaces
4502 *** Changes in GDB-4.0:
4506 Wide output is wrapped at good places to make the output more readable.
4508 Gdb now supports cross-debugging from a host machine of one type to a
4509 target machine of another type. Communication with the target system
4510 is over serial lines. The ``target'' command handles connecting to the
4511 remote system; the ``load'' command will download a program into the
4512 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4513 also supports debugging of realtime processes running under VxWorks,
4514 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4515 stub on the target system.
4517 New CPUs supported include the AMD 29000 and Intel 960.
4519 GDB now reads object files and symbol tables via a ``binary file''
4520 library, which allows a single copy of GDB to debug programs of multiple
4521 object file types such as a.out and coff.
4523 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4524 refcard.dvi and refcard.ps are available to format it).
4527 * Control-Variable user interface simplified
4529 All variables that control the operation of the debugger can be set
4530 by the ``set'' command, and displayed by the ``show'' command.
4532 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4533 ``Show prompt'' produces the response:
4534 Gdb's prompt is new-gdb=>.
4536 What follows are the NEW set commands. The command ``help set'' will
4537 print a complete list of old and new set commands. ``help set FOO''
4538 will give a longer description of the variable FOO. ``show'' will show
4539 all of the variable descriptions and their current settings.
4541 confirm on/off: Enables warning questions for operations that are
4542 hard to recover from, e.g. rerunning the program while
4543 it is already running. Default is ON.
4545 editing on/off: Enables EMACS style command line editing
4546 of input. Previous lines can be recalled with
4547 control-P, the current line can be edited with control-B,
4548 you can search for commands with control-R, etc.
4551 history filename NAME: NAME is where the gdb command history
4552 will be stored. The default is .gdb_history,
4553 or the value of the environment variable
4556 history size N: The size, in commands, of the command history. The
4557 default is 256, or the value of the environment variable
4560 history save on/off: If this value is set to ON, the history file will
4561 be saved after exiting gdb. If set to OFF, the
4562 file will not be saved. The default is OFF.
4564 history expansion on/off: If this value is set to ON, then csh-like
4565 history expansion will be performed on
4566 command line input. The default is OFF.
4568 radix N: Sets the default radix for input and output. It can be set
4569 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4570 in the current radix, so "set radix 10" is always a no-op.
4572 height N: This integer value is the number of lines on a page. Default
4573 is 24, the current `stty rows'' setting, or the ``li#''
4574 setting from the termcap entry matching the environment
4577 width N: This integer value is the number of characters on a line.
4578 Default is 80, the current `stty cols'' setting, or the ``co#''
4579 setting from the termcap entry matching the environment
4582 Note: ``set screensize'' is obsolete. Use ``set height'' and
4583 ``set width'' instead.
4585 print address on/off: Print memory addresses in various command displays,
4586 such as stack traces and structure values. Gdb looks
4587 more ``symbolic'' if you turn this off; it looks more
4588 ``machine level'' with it on. Default is ON.
4590 print array on/off: Prettyprint arrays. New convenient format! Default
4593 print demangle on/off: Print C++ symbols in "source" form if on,
4596 print asm-demangle on/off: Same, for assembler level printouts
4599 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4602 * Support for Epoch Environment.
4604 The epoch environment is a version of Emacs v18 with windowing. One
4605 new command, ``inspect'', is identical to ``print'', except that if you
4606 are running in the epoch environment, the value is printed in its own
4610 * Support for Shared Libraries
4612 GDB can now debug programs and core files that use SunOS shared libraries.
4613 Symbols from a shared library cannot be referenced
4614 before the shared library has been linked with the program (this
4615 happens after you type ``run'' and before the function main() is entered).
4616 At any time after this linking (including when examining core files
4617 from dynamically linked programs), gdb reads the symbols from each
4618 shared library when you type the ``sharedlibrary'' command.
4619 It can be abbreviated ``share''.
4621 sharedlibrary REGEXP: Load shared object library symbols for files
4622 matching a unix regular expression. No argument
4623 indicates to load symbols for all shared libraries.
4625 info sharedlibrary: Status of loaded shared libraries.
4630 A watchpoint stops execution of a program whenever the value of an
4631 expression changes. Checking for this slows down execution
4632 tremendously whenever you are in the scope of the expression, but is
4633 quite useful for catching tough ``bit-spreader'' or pointer misuse
4634 problems. Some machines such as the 386 have hardware for doing this
4635 more quickly, and future versions of gdb will use this hardware.
4637 watch EXP: Set a watchpoint (breakpoint) for an expression.
4639 info watchpoints: Information about your watchpoints.
4641 delete N: Deletes watchpoint number N (same as breakpoints).
4642 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4643 enable N: Re-enables watchpoint number N (same as breakpoints).
4646 * C++ multiple inheritance
4648 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4651 * C++ exception handling
4653 Gdb now supports limited C++ exception handling. Besides the existing
4654 ability to breakpoint on an exception handler, gdb can breakpoint on
4655 the raising of an exception (before the stack is peeled back to the
4658 catch FOO: If there is a FOO exception handler in the dynamic scope,
4659 set a breakpoint to catch exceptions which may be raised there.
4660 Multiple exceptions (``catch foo bar baz'') may be caught.
4662 info catch: Lists all exceptions which may be caught in the
4663 current stack frame.
4666 * Minor command changes
4668 The command ``call func (arg, arg, ...)'' now acts like the print
4669 command, except it does not print or save a value if the function's result
4670 is void. This is similar to dbx usage.
4672 The ``up'' and ``down'' commands now always print the frame they end up
4673 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4674 frames without printing.
4676 * New directory command
4678 'dir' now adds directories to the FRONT of the source search path.
4679 The path starts off empty. Source files that contain debug information
4680 about the directory in which they were compiled can be found even
4681 with an empty path; Sun CC and GCC include this information. If GDB can't
4682 find your source file in the current directory, type "dir .".
4684 * Configuring GDB for compilation
4686 For normal use, type ``./configure host''. See README or gdb.texinfo
4689 GDB now handles cross debugging. If you are remotely debugging between
4690 two different machines, type ``./configure host -target=targ''.
4691 Host is the machine where GDB will run; targ is the machine
4692 where the program that you are debugging will run.