1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.4
8 ** The "maint set python print-stack on|off" is now deleted.
10 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
11 apply "flag enum"-style pretty-printing to any enum.
13 ** gdb.lookup_symbol can now work when there is no current frame.
15 ** gdb.Symbol now has a 'line' attribute, holding the line number in
16 the source at which the symbol was defined.
18 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
19 method 'value'. The former indicates whether the symbol needs a
20 frame in order to compute its value, and the latter computes the
23 * GDBserver now supports stdio connections.
24 E.g. (gdb) target remote | ssh myhost gdbserver - hello
26 * The binary "gdbtui" can no longer be built or installed.
27 Use "gdb -tui" instead.
29 * GDB will now print "flag" enums specially. A flag enum is one where
30 all the enumerator values have no bits in common when pairwise
31 "and"ed. When printing a value whose type is a flag enum, GDB will
32 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
33 (gdb) print (enum E) 3
36 * The filename part of a linespec will now match trailing components
37 of a source file name. For example, "break gcc/expr.c:1000" will
38 now set a breakpoint in build/gcc/expr.c, but not
41 * The "info proc" and "generate-core-file" commands will now also
42 work on remote targets connected to GDBserver on Linux.
44 * The command "info catch" has been removed. It has been disabled
49 ** "catch load" and "catch unload" can be used to stop when a shared
50 library is loaded or unloaded, respectively.
52 ** "enable count" can be used to auto-disable a breakpoint after
57 Renesas RL78 rl78-*-elf
59 *** Changes in GDB 7.4
61 * GDB now handles ambiguous linespecs more consistently; the existing
62 FILE:LINE support has been expanded to other types of linespecs. A
63 breakpoint will now be set on all matching locations in all
64 inferiors, and locations will be added or removed according to
67 * GDB now allows you to skip uninteresting functions and files when
68 stepping with the "skip function" and "skip file" commands.
70 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
71 and "show remote hardware-watchpoint-length-limit". These allows to
72 set or show the maximum length limit (in bytes) of a remote
73 target hardware watchpoint.
75 This allows e.g. to use "unlimited" hardware watchpoints with the
76 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
77 watchpoints are slower than real hardware watchpoints but are
78 significantly faster than gdb software watchpoints.
82 ** The register_pretty_printer function in module gdb.printing now takes
83 an optional `replace' argument. If True, the new printer replaces any
86 ** The "maint set python print-stack on|off" command has been
87 deprecated and will be deleted in GDB 7.5.
88 A new command: "set python print-stack none|full|message" has
89 replaced it. Additionally, the default for "print-stack" is
90 now "message", which just prints the error message without
93 ** A prompt substitution hook (prompt_hook) is now available to the
96 ** A new Python module, gdb.prompt has been added to the GDB Python
97 modules library. This module provides functionality for
98 escape sequences in prompts (used by set/show
99 extended-prompt). These escape sequences are replaced by their
102 ** Python commands and convenience-functions located in
103 'data-directory'/python/gdb/command and
104 'data-directory'/python/gdb/function are now automatically loaded
107 ** Blocks now provide four new attributes. global_block and
108 static_block will return the global and static blocks
109 respectively. is_static and is_global are boolean attributes
110 that indicate if the block is one of those two types.
112 ** Symbols now provide the "type" attribute, the type of the symbol.
114 ** The "gdb.breakpoint" function has been deprecated in favor of
117 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
118 of a function. This class is based on the "finish" command
119 available in the CLI.
121 ** Type objects for struct and union types now allow access to
122 the fields using standard Python dictionary (mapping) methods.
123 For example, "some_type['myfield']" now works, as does
126 ** A new event "gdb.new_objfile" has been added, triggered by loading a
129 ** A new function, "deep_items" has been added to the gdb.types
130 module in the GDB Python modules library. This function returns
131 an iterator over the fields of a struct or union type. Unlike
132 the standard Python "iteritems" method, it will recursively traverse
133 any anonymous fields.
137 ** "*stopped" events can report several new "reason"s, such as
140 ** Breakpoint changes are now notified using new async records, like
141 "=breakpoint-modified".
143 ** New command -ada-task-info.
145 * libthread-db-search-path now supports two special values: $sdir and $pdir.
146 $sdir specifies the default system locations of shared libraries.
147 $pdir specifies the directory where the libpthread used by the application
150 GDB no longer looks in $sdir and $pdir after it has searched the directories
151 mentioned in libthread-db-search-path. If you want to search those
152 directories, they must be specified in libthread-db-search-path.
153 The default value of libthread-db-search-path on GNU/Linux and Solaris
154 systems is now "$sdir:$pdir".
156 $pdir is not supported by gdbserver, it is currently ignored.
157 $sdir is supported by gdbserver.
159 * New configure option --with-iconv-bin.
160 When using the internationalization support like the one in the GNU C
161 library, GDB will invoke the "iconv" program to get a list of supported
162 character sets. If this program lives in a non-standard location, one can
163 use this option to specify where to find it.
165 * When natively debugging programs on PowerPC BookE processors running
166 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
167 watchpoints, which specify a mask in addition to an address to watch.
168 The mask specifies that some bits of an address (the bits which are
169 reset in the mask) should be ignored when matching the address accessed
170 by the inferior against the watchpoint address. See the "PowerPC Embedded"
171 section in the user manual for more details.
173 * The new option --once causes GDBserver to stop listening for connections once
174 the first connection is made. The listening port used by GDBserver will
175 become available after that.
177 * New commands "info macros" and "alias" have been added.
179 * New function parameters suffix @entry specifies value of function parameter
180 at the time the function got called. Entry values are available only since
186 "!" is now an alias of the "shell" command.
187 Note that no space is needed between "!" and SHELL COMMAND.
191 watch EXPRESSION mask MASK_VALUE
192 The watch command now supports the mask argument which allows creation
193 of masked watchpoints, if the current architecture supports this feature.
195 info auto-load-scripts [REGEXP]
196 This command was formerly named "maintenance print section-scripts".
197 It is now generally useful and is no longer a maintenance-only command.
199 info macro [-all] [--] MACRO
200 The info macro command has new options `-all' and `--'. The first for
201 printing all definitions of a macro. The second for explicitly specifying
202 the end of arguments and the beginning of the macro name in case the macro
203 name starts with a hyphen.
205 collect[/s] EXPRESSIONS
206 The tracepoint collect command now takes an optional modifier "/s"
207 that directs it to dereference pointer-to-character types and
208 collect the bytes of memory up to a zero byte. The behavior is
209 similar to what you see when you use the regular print command on a
210 string. An optional integer following the "/s" sets a bound on the
211 number of bytes that will be collected.
214 The trace start command now interprets any supplied arguments as a
215 note to be recorded with the trace run, with an effect similar to
216 setting the variable trace-notes.
219 The trace stop command now interprets any arguments as a note to be
220 mentioned along with the tstatus report that the trace was stopped
221 with a command. The effect is similar to setting the variable
224 * Tracepoints can now be enabled and disabled at any time after a trace
225 experiment has been started using the standard "enable" and "disable"
226 commands. It is now possible to start a trace experiment with no enabled
227 tracepoints; GDB will display a warning, but will allow the experiment to
228 begin, assuming that tracepoints will be enabled as needed while the trace
231 * Fast tracepoints on 32-bit x86-architectures can now be placed at
232 locations with 4-byte instructions, when they were previously
233 limited to locations with instructions of 5 bytes or longer.
239 Set the GDB prompt, and allow escape sequences to be inserted to
240 display miscellaneous information (see 'help set extended-prompt'
241 for the list of sequences). This prompt (and any information
242 accessed through the escape sequences) is updated every time the
245 set print entry-values (both|compact|default|if-needed|no|only|preferred)
246 show print entry-values
247 Set printing of frame argument values at function entry. In some cases
248 GDB can determine the value of function argument which was passed by the
249 function caller, even if the value was modified inside the called function.
251 set debug entry-values
252 show debug entry-values
253 Control display of debugging info for determining frame argument values at
254 function entry and virtual tail call frames.
256 set basenames-may-differ
257 show basenames-may-differ
258 Set whether a source file may have multiple base names.
259 (A "base name" is the name of a file with the directory part removed.
260 Example: The base name of "/home/user/hello.c" is "hello.c".)
261 If set, GDB will canonicalize file names (e.g., expand symlinks)
262 before comparing them. Canonicalization is an expensive operation,
263 but it allows the same file be known by more than one base name.
264 If not set (the default), all source files are assumed to have just
265 one base name, and gdb will do file name comparisons more efficiently.
271 Set a user name and notes for the current and any future trace runs.
272 This is useful for long-running and/or disconnected traces, to
273 inform others (or yourself) as to who is running the trace, supply
274 contact information, or otherwise explain what is going on.
277 show trace-stop-notes
278 Set a note attached to the trace run, that is displayed when the
279 trace has been stopped by a tstop command. This is useful for
280 instance as an explanation, if you are stopping a trace run that was
281 started by someone else.
287 Dynamically enable a tracepoint in a started trace experiment.
291 Dynamically disable a tracepoint in a started trace experiment.
295 Set the user and notes of the trace run.
299 Query the current status of a tracepoint.
303 Query the minimum length of instruction at which a fast tracepoint may
306 * Dcache size (number of lines) and line-size are now runtime-configurable
307 via "set dcache line" and "set dcache line-size" commands.
311 Texas Instruments TMS320C6x tic6x-*-*
315 Renesas RL78 rl78-*-elf
317 *** Changes in GDB 7.3.1
319 * The build failure for NetBSD and OpenBSD targets have now been fixed.
321 *** Changes in GDB 7.3
323 * GDB has a new command: "thread find [REGEXP]".
324 It finds the thread id whose name, target id, or thread extra info
325 matches the given regular expression.
327 * The "catch syscall" command now works on mips*-linux* targets.
329 * The -data-disassemble MI command now supports modes 2 and 3 for
330 dumping the instruction opcodes.
332 * New command line options
334 -data-directory DIR Specify DIR as the "data-directory".
335 This is mostly for testing purposes.
337 * The "maint set python auto-load on|off" command has been renamed to
338 "set auto-load-scripts on|off".
340 * GDB has a new command: "set directories".
341 It is like the "dir" command except that it replaces the
342 source path list instead of augmenting it.
344 * GDB now understands thread names.
346 On GNU/Linux, "info threads" will display the thread name as set by
347 prctl or pthread_setname_np.
349 There is also a new command, "thread name", which can be used to
350 assign a name internally for GDB to display.
353 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
354 has been integrated into GDB.
358 ** The function gdb.Write now accepts an optional keyword 'stream'.
359 This keyword, when provided, will direct the output to either
360 stdout, stderr, or GDB's logging output.
362 ** Parameters can now be be sub-classed in Python, and in particular
363 you may implement the get_set_doc and get_show_doc functions.
364 This improves how Parameter set/show documentation is processed
365 and allows for more dynamic content.
367 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
368 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
369 have an is_valid method.
371 ** Breakpoints can now be sub-classed in Python, and in particular
372 you may implement a 'stop' function that is executed each time
373 the inferior reaches that breakpoint.
375 ** New function gdb.lookup_global_symbol looks up a global symbol.
377 ** GDB values in Python are now callable if the value represents a
378 function. For example, if 'some_value' represents a function that
379 takes two integer parameters and returns a value, you can call
380 that function like so:
382 result = some_value (10,20)
384 ** Module gdb.types has been added.
385 It contains a collection of utilities for working with gdb.Types objects:
386 get_basic_type, has_field, make_enum_dict.
388 ** Module gdb.printing has been added.
389 It contains utilities for writing and registering pretty-printers.
390 New classes: PrettyPrinter, SubPrettyPrinter,
391 RegexpCollectionPrettyPrinter.
392 New function: register_pretty_printer.
394 ** New commands "info pretty-printers", "enable pretty-printer" and
395 "disable pretty-printer" have been added.
397 ** gdb.parameter("directories") is now available.
399 ** New function gdb.newest_frame returns the newest frame in the
402 ** The gdb.InferiorThread class has a new "name" attribute. This
403 holds the thread's name.
405 ** Python Support for Inferior events.
406 Python scripts can add observers to be notified of events
407 occurring in the process being debugged.
408 The following events are currently supported:
409 - gdb.events.cont Continue event.
410 - gdb.events.exited Inferior exited event.
411 - gdb.events.stop Signal received, and Breakpoint hit events.
415 ** GDB now puts template parameters in scope when debugging in an
416 instantiation. For example, if you have:
418 template<int X> int func (void) { return X; }
420 then if you step into func<5>, "print X" will show "5". This
421 feature requires proper debuginfo support from the compiler; it
422 was added to GCC 4.5.
424 ** The motion commands "next", "finish", "until", and "advance" now
425 work better when exceptions are thrown. In particular, GDB will
426 no longer lose control of the inferior; instead, the GDB will
427 stop the inferior at the point at which the exception is caught.
428 This functionality requires a change in the exception handling
429 code that was introduced in GCC 4.5.
431 * GDB now follows GCC's rules on accessing volatile objects when
432 reading or writing target state during expression evaluation.
433 One notable difference to prior behavior is that "print x = 0"
434 no longer generates a read of x; the value of the assignment is
435 now always taken directly from the value being assigned.
437 * GDB now has some support for using labels in the program's source in
438 linespecs. For instance, you can use "advance label" to continue
439 execution to a label.
441 * GDB now has support for reading and writing a new .gdb_index
442 section. This section holds a fast index of DWARF debugging
443 information and can be used to greatly speed up GDB startup and
444 operation. See the documentation for `save gdb-index' for details.
446 * The "watch" command now accepts an optional "-location" argument.
447 When used, this causes GDB to watch the memory referred to by the
448 expression. Such a watchpoint is never deleted due to it going out
451 * GDB now supports thread debugging of core dumps on GNU/Linux.
453 GDB now activates thread debugging using the libthread_db library
454 when debugging GNU/Linux core dumps, similarly to when debugging
455 live processes. As a result, when debugging a core dump file, GDB
456 is now able to display pthread_t ids of threads. For example, "info
457 threads" shows the same output as when debugging the process when it
458 was live. In earlier releases, you'd see something like this:
461 * 1 LWP 6780 main () at main.c:10
463 While now you see this:
466 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
468 It is also now possible to inspect TLS variables when debugging core
471 When debugging a core dump generated on a machine other than the one
472 used to run GDB, you may need to point GDB at the correct
473 libthread_db library with the "set libthread-db-search-path"
474 command. See the user manual for more details on this command.
476 * When natively debugging programs on PowerPC BookE processors running
477 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
478 which stop execution of the inferior whenever it executes an instruction
479 at any address within the specified range. See the "PowerPC Embedded"
480 section in the user manual for more details.
482 * New features in the GDB remote stub, GDBserver
484 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
485 and i686 LynxOS (version 5.x).
487 ** GDBserver is now supported on Blackfin Linux.
489 * New native configurations
491 ia64 HP-UX ia64-*-hpux*
495 Analog Devices, Inc. Blackfin Processor bfin-*
497 * Ada task switching is now supported on sparc-elf targets when
498 debugging a program using the Ravenscar Profile. For more information,
499 see the "Tasking Support when using the Ravenscar Profile" section
500 in the GDB user manual.
502 * Guile support was removed.
504 * New features in the GNU simulator
506 ** The --map-info flag lists all known core mappings.
508 ** CFI flashes may be simulated via the "cfi" device.
510 *** Changes in GDB 7.2
512 * Shared library support for remote targets by default
514 When GDB is configured for a generic, non-OS specific target, like
515 for example, --target=arm-eabi or one of the many *-*-elf targets,
516 GDB now queries remote stubs for loaded shared libraries using the
517 `qXfer:libraries:read' packet. Previously, shared library support
518 was always disabled for such configurations.
522 ** Argument Dependent Lookup (ADL)
524 In C++ ADL lookup directs function search to the namespaces of its
525 arguments even if the namespace has not been imported.
535 Here the compiler will search for `foo' in the namespace of 'b'
536 and find A::foo. GDB now supports this. This construct is commonly
537 used in the Standard Template Library for operators.
539 ** Improved User Defined Operator Support
541 In addition to member operators, GDB now supports lookup of operators
542 defined in a namespace and imported with a `using' directive, operators
543 defined in the global scope, operators imported implicitly from an
544 anonymous namespace, and the ADL operators mentioned in the previous
546 GDB now also supports proper overload resolution for all the previously
547 mentioned flavors of operators.
549 ** static const class members
551 Printing of static const class members that are initialized in the
552 class definition has been fixed.
554 * Windows Thread Information Block access.
556 On Windows targets, GDB now supports displaying the Windows Thread
557 Information Block (TIB) structure. This structure is visible either
558 by using the new command `info w32 thread-information-block' or, by
559 dereferencing the new convenience variable named `$_tlb', a
560 thread-specific pointer to the TIB. This feature is also supported
561 when remote debugging using GDBserver.
565 Static tracepoints are calls in the user program into a tracing
566 library. One such library is a port of the LTTng kernel tracer to
567 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
568 When debugging with GDBserver, GDB now supports combining the GDB
569 tracepoint machinery with such libraries. For example: the user can
570 use GDB to probe a static tracepoint marker (a call from the user
571 program into the tracing library) with the new "strace" command (see
572 "New commands" below). This creates a "static tracepoint" in the
573 breakpoint list, that can be manipulated with the same feature set
574 as fast and regular tracepoints. E.g., collect registers, local and
575 global variables, collect trace state variables, and define
576 tracepoint conditions. In addition, the user can collect extra
577 static tracepoint marker specific data, by collecting the new
578 $_sdata internal variable. When analyzing the trace buffer, you can
579 inspect $_sdata like any other variable available to GDB. For more
580 information, see the "Tracepoints" chapter in GDB user manual. New
581 remote packets have been defined to support static tracepoints, see
582 the "New remote packets" section below.
584 * Better reconstruction of tracepoints after disconnected tracing
586 GDB will attempt to download the original source form of tracepoint
587 definitions when starting a trace run, and then will upload these
588 upon reconnection to the target, resulting in a more accurate
589 reconstruction of the tracepoints that are in use on the target.
593 You can now exercise direct control over the ways that GDB can
594 affect your program. For instance, you can disallow the setting of
595 breakpoints, so that the program can run continuously (assuming
596 non-stop mode). In addition, the "observer" variable is available
597 to switch all of the different controls; in observer mode, GDB
598 cannot affect the target's behavior at all, which is useful for
599 tasks like diagnosing live systems in the field.
601 * The new convenience variable $_thread holds the number of the
608 Return the address of the Windows Thread Information Block of a given thread.
612 In response to several of the tracepoint packets, the target may now
613 also respond with a number of intermediate `qRelocInsn' request
614 packets before the final result packet, to have GDB handle
615 relocating an instruction to execute at a different address. This
616 is particularly useful for stubs that support fast tracepoints. GDB
617 reports support for this feature in the qSupported packet.
621 List static tracepoint markers in the target program.
625 List static tracepoint markers at a given address in the target
628 qXfer:statictrace:read
630 Read the static trace data collected (by a `collect $_sdata'
631 tracepoint action). The remote stub reports support for this packet
632 to gdb's qSupported query.
636 Send the current settings of GDB's permission flags.
640 Send part of the source (textual) form of a tracepoint definition,
641 which includes location, conditional, and action list.
643 * The source command now accepts a -s option to force searching for the
644 script in the source search path even if the script name specifies
647 * New features in the GDB remote stub, GDBserver
649 - GDBserver now support tracepoints (including fast tracepoints, and
650 static tracepoints). The feature is currently supported by the
651 i386-linux and amd64-linux builds. See the "Tracepoints support
652 in gdbserver" section in the manual for more information.
654 GDBserver JIT compiles the tracepoint's conditional agent
655 expression bytecode into native code whenever possible for low
656 overhead dynamic tracepoints conditionals. For such tracepoints,
657 an expression that examines program state is evaluated when the
658 tracepoint is reached, in order to determine whether to capture
659 trace data. If the condition is simple and false, processing the
660 tracepoint finishes very quickly and no data is gathered.
662 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
663 for static tracepoints support.
665 - GDBserver now supports x86_64 Windows 64-bit debugging.
667 * GDB now sends xmlRegisters= in qSupported packet to indicate that
668 it understands register description.
670 * The --batch flag now disables pagination and queries.
672 * X86 general purpose registers
674 GDB now supports reading/writing byte, word and double-word x86
675 general purpose registers directly. This means you can use, say,
676 $ah or $ax to refer, respectively, to the byte register AH and
677 16-bit word register AX that are actually portions of the 32-bit
678 register EAX or 64-bit register RAX.
680 * The `commands' command now accepts a range of breakpoints to modify.
681 A plain `commands' following a command that creates multiple
682 breakpoints affects all the breakpoints set by that command. This
683 applies to breakpoints set by `rbreak', and also applies when a
684 single `break' command creates multiple breakpoints (e.g.,
685 breakpoints on overloaded c++ functions).
687 * The `rbreak' command now accepts a filename specification as part of
688 its argument, limiting the functions selected by the regex to those
689 in the specified file.
691 * Support for remote debugging Windows and SymbianOS shared libraries
692 from Unix hosts has been improved. Non Windows GDB builds now can
693 understand target reported file names that follow MS-DOS based file
694 system semantics, such as file names that include drive letters and
695 use the backslash character as directory separator. This makes it
696 possible to transparently use the "set sysroot" and "set
697 solib-search-path" on Unix hosts to point as host copies of the
698 target's shared libraries. See the new command "set
699 target-file-system-kind" described below, and the "Commands to
700 specify files" section in the user manual for more information.
704 eval template, expressions...
705 Convert the values of one or more expressions under the control
706 of the string template to a command line, and call it.
708 set target-file-system-kind unix|dos-based|auto
709 show target-file-system-kind
710 Set or show the assumed file system kind for target reported file
713 save breakpoints <filename>
714 Save all current breakpoint definitions to a file suitable for use
715 in a later debugging session. To read the saved breakpoint
716 definitions, use the `source' command.
718 `save tracepoints' is a new alias for `save-tracepoints'. The latter
721 info static-tracepoint-markers
722 Display information about static tracepoint markers in the target.
724 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
725 Define a static tracepoint by probing a marker at the given
726 function, line, address, or marker ID.
730 Enable and disable observer mode.
732 set may-write-registers on|off
733 set may-write-memory on|off
734 set may-insert-breakpoints on|off
735 set may-insert-tracepoints on|off
736 set may-insert-fast-tracepoints on|off
737 set may-interrupt on|off
738 Set individual permissions for GDB effects on the target. Note that
739 some of these settings can have undesirable or surprising
740 consequences, particularly when changed in the middle of a session.
741 For instance, disabling the writing of memory can prevent
742 breakpoints from being inserted, cause single-stepping to fail, or
743 even crash your program, if you disable after breakpoints have been
744 inserted. However, GDB should not crash.
746 set record memory-query on|off
747 show record memory-query
748 Control whether to stop the inferior if memory changes caused
749 by an instruction cannot be recorded.
754 The disassemble command now supports "start,+length" form of two arguments.
758 ** GDB now provides a new directory location, called the python directory,
759 where Python scripts written for GDB can be installed. The location
760 of that directory is <data-directory>/python, where <data-directory>
761 is the GDB data directory. For more details, see section `Scripting
762 GDB using Python' in the manual.
764 ** The GDB Python API now has access to breakpoints, symbols, symbol
765 tables, program spaces, inferiors, threads and frame's code blocks.
766 Additionally, GDB Parameters can now be created from the API, and
767 manipulated via set/show in the CLI.
769 ** New functions gdb.target_charset, gdb.target_wide_charset,
770 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
772 ** New exception gdb.GdbError.
774 ** Pretty-printers are now also looked up in the current program space.
776 ** Pretty-printers can now be individually enabled and disabled.
778 ** GDB now looks for names of Python scripts to auto-load in a
779 special section named `.debug_gdb_scripts', in addition to looking
780 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
782 * Tracepoint actions were unified with breakpoint commands. In particular,
783 there are no longer differences in "info break" output for breakpoints and
784 tracepoints and the "commands" command can be used for both tracepoints and
789 ARM Symbian arm*-*-symbianelf*
791 * D language support.
792 GDB now supports debugging programs written in the D programming
795 * GDB now supports the extended ptrace interface for PowerPC which is
796 available since Linux kernel version 2.6.34. This automatically enables
797 any hardware breakpoints and additional hardware watchpoints available in
798 the processor. The old ptrace interface exposes just one hardware
799 watchpoint and no hardware breakpoints.
801 * GDB is now able to use the Data Value Compare (DVC) register available on
802 embedded PowerPC processors to implement in hardware simple watchpoint
803 conditions of the form:
805 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
807 This works in native GDB running on Linux kernels with the extended ptrace
808 interface mentioned above.
810 *** Changes in GDB 7.1
816 GDB now supports importing of namespaces in C++. This enables the
817 user to inspect variables from imported namespaces. Support for
818 namepace aliasing has also been added. So, if a namespace is
819 aliased in the current scope (e.g. namepace C=A; ) the user can
820 print variables using the alias (e.g. (gdb) print C::x).
824 All known bugs relating to the printing of virtual base class were
825 fixed. It is now possible to call overloaded static methods using a
830 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
831 and reinterpret_cast<> are now handled by the C++ expression parser.
835 Xilinx MicroBlaze microblaze-*-*
840 Xilinx MicroBlaze microblaze
843 * Multi-program debugging.
845 GDB now has support for multi-program (a.k.a. multi-executable or
846 multi-exec) debugging. This allows for debugging multiple inferiors
847 simultaneously each running a different program under the same GDB
848 session. See "Debugging Multiple Inferiors and Programs" in the
849 manual for more information. This implied some user visible changes
850 in the multi-inferior support. For example, "info inferiors" now
851 lists inferiors that are not running yet or that have exited
852 already. See also "New commands" and "New options" below.
854 * New tracing features
856 GDB's tracepoint facility now includes several new features:
858 ** Trace state variables
860 GDB tracepoints now include support for trace state variables, which
861 are variables managed by the target agent during a tracing
862 experiment. They are useful for tracepoints that trigger each
863 other, so for instance one tracepoint can count hits in a variable,
864 and then a second tracepoint has a condition that is true when the
865 count reaches a particular value. Trace state variables share the
866 $-syntax of GDB convenience variables, and can appear in both
867 tracepoint actions and condition expressions. Use the "tvariable"
868 command to create, and "info tvariables" to view; see "Trace State
869 Variables" in the manual for more detail.
873 GDB now includes an option for defining fast tracepoints, which
874 targets may implement more efficiently, such as by installing a jump
875 into the target agent rather than a trap instruction. The resulting
876 speedup can be by two orders of magnitude or more, although the
877 tradeoff is that some program locations on some target architectures
878 might not allow fast tracepoint installation, for instance if the
879 instruction to be replaced is shorter than the jump. To request a
880 fast tracepoint, use the "ftrace" command, with syntax identical to
881 the regular trace command.
883 ** Disconnected tracing
885 It is now possible to detach GDB from the target while it is running
886 a trace experiment, then reconnect later to see how the experiment
887 is going. In addition, a new variable disconnected-tracing lets you
888 tell the target agent whether to continue running a trace if the
889 connection is lost unexpectedly.
893 GDB now has the ability to save the trace buffer into a file, and
894 then use that file as a target, similarly to you can do with
895 corefiles. You can select trace frames, print data that was
896 collected in them, and use tstatus to display the state of the
897 tracing run at the moment that it was saved. To create a trace
898 file, use "tsave <filename>", and to use it, do "target tfile
901 ** Circular trace buffer
903 You can ask the target agent to handle the trace buffer as a
904 circular buffer, discarding the oldest trace frames to make room for
905 newer ones, by setting circular-trace-buffer to on. This feature may
906 not be available for all target agents.
911 The disassemble command, when invoked with two arguments, now requires
912 the arguments to be comma-separated.
915 The info variables command now displays variable definitions. Files
916 which only declare a variable are not shown.
919 The source command is now capable of sourcing Python scripts.
920 This feature is dependent on the debugger being build with Python
923 Related to this enhancement is also the introduction of a new command
924 "set script-extension" (see below).
926 * New commands (for set/show, see "New options" below)
928 record save [<FILENAME>]
929 Save a file (in core file format) containing the process record
930 execution log for replay debugging at a later time.
932 record restore <FILENAME>
933 Restore the process record execution log that was saved at an
934 earlier time, for replay debugging.
936 add-inferior [-copies <N>] [-exec <FILENAME>]
939 clone-inferior [-copies <N>] [ID]
940 Make a new inferior ready to execute the same program another
946 maint info program-spaces
947 List the program spaces loaded into GDB.
949 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
950 show remote interrupt-sequence
951 Allow the user to select one of ^C, a BREAK signal or BREAK-g
952 as the sequence to the remote target in order to interrupt the execution.
953 Ctrl-C is a default. Some system prefers BREAK which is high level of
954 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
955 Magic SysRq g. It is BREAK signal and character 'g'.
957 set remote interrupt-on-connect [on | off]
958 show remote interrupt-on-connect
959 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
960 remote target when gdb connects to it. This is needed when you debug
963 set remotebreak [on | off]
965 Deprecated. Use "set/show remote interrupt-sequence" instead.
967 tvariable $NAME [ = EXP ]
968 Create or modify a trace state variable.
971 List trace state variables and their values.
973 delete tvariable $NAME ...
974 Delete one or more trace state variables.
977 Evaluate the given expressions without collecting anything into the
978 trace buffer. (Valid in tracepoint actions only.)
980 ftrace FN / FILE:LINE / *ADDR
981 Define a fast tracepoint at the given function, line, or address.
983 * New expression syntax
985 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
986 GDB now parses 0b101010 identically with 42.
990 set follow-exec-mode new|same
991 show follow-exec-mode
992 Control whether GDB reuses the same inferior across an exec call or
993 creates a new one. This is useful to be able to restart the old
994 executable after the inferior having done an exec call.
996 set default-collect EXPR, ...
998 Define a list of expressions to be collected at each tracepoint.
999 This is a useful way to ensure essential items are not overlooked,
1000 such as registers or a critical global variable.
1002 set disconnected-tracing
1003 show disconnected-tracing
1004 If set to 1, the target is instructed to continue tracing if it
1005 loses its connection to GDB. If 0, the target is to stop tracing
1008 set circular-trace-buffer
1009 show circular-trace-buffer
1010 If set to on, the target is instructed to use a circular trace buffer
1011 and discard the oldest trace frames instead of stopping the trace due
1012 to a full trace buffer. If set to off, the trace stops when the buffer
1013 fills up. Some targets may not support this.
1015 set script-extension off|soft|strict
1016 show script-extension
1017 If set to "off", the debugger does not perform any script language
1018 recognition, and all sourced files are assumed to be GDB scripts.
1019 If set to "soft" (the default), files are sourced according to
1020 filename extension, falling back to GDB scripts if the first
1022 If set to "strict", files are sourced according to filename extension.
1024 set ada trust-PAD-over-XVS on|off
1025 show ada trust-PAD-over-XVS
1026 If off, activate a workaround against a bug in the debugging information
1027 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1028 the GCC sources for more information about the GNAT encoding and
1029 PAD types in particular). It is always safe to set this option to
1030 off, but this introduces a slight performance penalty. The default
1033 * Python API Improvements
1035 ** GDB provides the new class gdb.LazyString. This is useful in
1036 some pretty-printing cases. The new method gdb.Value.lazy_string
1037 provides a simple way to create objects of this type.
1039 ** The fields returned by gdb.Type.fields now have an
1040 `is_base_class' attribute.
1042 ** The new method gdb.Type.range returns the range of an array type.
1044 ** The new method gdb.parse_and_eval can be used to parse and
1045 evaluate an expression.
1047 * New remote packets
1050 Define a trace state variable.
1053 Get the current value of a trace state variable.
1056 Set desired tracing behavior upon disconnection.
1059 Set the trace buffer to be linear or circular.
1062 Get data about the tracepoints currently in use.
1066 Process record now works correctly with hardware watchpoints.
1068 Multiple bug fixes have been made to the mips-irix port, making it
1069 much more reliable. In particular:
1070 - Debugging threaded applications is now possible again. Previously,
1071 GDB would hang while starting the program, or while waiting for
1072 the program to stop at a breakpoint.
1073 - Attaching to a running process no longer hangs.
1074 - An error occurring while loading a core file has been fixed.
1075 - Changing the value of the PC register now works again. This fixes
1076 problems observed when using the "jump" command, or when calling
1077 a function from GDB, or even when assigning a new value to $pc.
1078 - With the "finish" and "return" commands, the return value for functions
1079 returning a small array is now correctly printed.
1080 - It is now possible to break on shared library code which gets executed
1081 during a shared library init phase (code executed while executing
1082 their .init section). Previously, the breakpoint would have no effect.
1083 - GDB is now able to backtrace through the signal handler for
1084 non-threaded programs.
1086 PIE (Position Independent Executable) programs debugging is now supported.
1087 This includes debugging execution of PIC (Position Independent Code) shared
1088 libraries although for that, it should be possible to run such libraries as an
1091 *** Changes in GDB 7.0
1093 * GDB now has an interface for JIT compilation. Applications that
1094 dynamically generate code can create symbol files in memory and register
1095 them with GDB. For users, the feature should work transparently, and
1096 for JIT developers, the interface is documented in the GDB manual in the
1097 "JIT Compilation Interface" chapter.
1099 * Tracepoints may now be conditional. The syntax is as for
1100 breakpoints; either an "if" clause appended to the "trace" command,
1101 or the "condition" command is available. GDB sends the condition to
1102 the target for evaluation using the same bytecode format as is used
1103 for tracepoint actions.
1105 * The disassemble command now supports: an optional /r modifier, print the
1106 raw instructions in hex as well as in symbolic form, and an optional /m
1107 modifier to print mixed source+assembly.
1109 * Process record and replay
1111 In a architecture environment that supports ``process record and
1112 replay'', ``process record and replay'' target can record a log of
1113 the process execution, and replay it with both forward and reverse
1116 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1117 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1118 set execution-direction {forward|reverse}, for targets that support
1121 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1122 feature is available with a native GDB running on kernel version
1125 * GDB now has support for multi-byte and wide character sets on the
1126 target. Strings whose character type is wchar_t, char16_t, or
1127 char32_t are now correctly printed. GDB supports wide- and unicode-
1128 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1129 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1130 `printf'. This feature requires iconv to work properly; if your
1131 system does not have a working iconv, GDB can use GNU libiconv. See
1132 the installation instructions for more information.
1134 * GDB now supports automatic retrieval of shared library files from
1135 remote targets. To use this feature, specify a system root that begins
1136 with the `remote:' prefix, either via the `set sysroot' command or via
1137 the `--with-sysroot' configure-time option.
1139 * "info sharedlibrary" now takes an optional regex of libraries to show,
1140 and it now reports if a shared library has no debugging information.
1142 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1143 now complete on file names.
1145 * When completing in expressions, gdb will attempt to limit
1146 completions to allowable structure or union fields, where appropriate.
1147 For instance, consider:
1149 # struct example { int f1; double f2; };
1150 # struct example variable;
1153 If the user types TAB at the end of this command line, the available
1154 completions will be "f1" and "f2".
1156 * Inlined functions are now supported. They show up in backtraces, and
1157 the "step", "next", and "finish" commands handle them automatically.
1159 * GDB now supports the token-splicing (##) and stringification (#)
1160 operators when expanding macros. It also supports variable-arity
1163 * GDB now supports inspecting extra signal information, exported by
1164 the new $_siginfo convenience variable. The feature is currently
1165 implemented on linux ARM, i386 and amd64.
1167 * GDB can now display the VFP floating point registers and NEON vector
1168 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1169 can provide these registers (requires Linux 2.6.30 or later). Remote
1170 and simulator targets may also provide them.
1172 * New remote packets
1175 Search memory for a sequence of bytes.
1178 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1179 operation over reliable transport links. Use of this packet is
1180 controlled by the `set remote noack-packet' command.
1183 Kill the process with the specified process ID. Use this in preference
1184 to `k' when multiprocess protocol extensions are supported.
1187 Obtains additional operating system information
1191 Read or write additional signal information.
1193 * Removed remote protocol undocumented extension
1195 An undocumented extension to the remote protocol's `S' stop reply
1196 packet that permited the stub to pass a process id was removed.
1197 Remote servers should use the `T' stop reply packet instead.
1199 * GDB now supports multiple function calling conventions according to the
1200 DWARF-2 DW_AT_calling_convention function attribute.
1202 * The SH target utilizes the aforementioned change to distinguish between gcc
1203 and Renesas calling convention. It also adds the new CLI commands
1204 `set/show sh calling-convention'.
1206 * GDB can now read compressed debug sections, as produced by GNU gold
1207 with the --compress-debug-sections=zlib flag.
1209 * 64-bit core files are now supported on AIX.
1211 * Thread switching is now supported on Tru64.
1213 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1214 which will be allocated using malloc later in program execution.
1216 * The qXfer:libraries:read remote procotol packet now allows passing a
1217 list of section offsets.
1219 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1220 conditions handling signals delivered during attach or thread creation
1221 have also been fixed.
1223 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1224 From the user's standpoint, all unqualified instances of True and False
1225 are treated as the standard definitions, regardless of context.
1227 * GDB now parses C++ symbol and type names more flexibly. For
1230 template<typename T> class C { };
1233 GDB will now correctly handle all of:
1235 ptype C<char const *>
1236 ptype C<char const*>
1237 ptype C<const char *>
1238 ptype C<const char*>
1240 * New features in the GDB remote stub, gdbserver
1242 - The "--wrapper" command-line argument tells gdbserver to use a
1243 wrapper program to launch programs for debugging.
1245 - On PowerPC and S/390 targets, it is now possible to use a single
1246 gdbserver executable to debug both 32-bit and 64-bit programs.
1247 (This requires gdbserver itself to be built as a 64-bit executable.)
1249 - gdbserver uses the new noack protocol mode for TCP connections to
1250 reduce communications latency, if also supported and enabled in GDB.
1252 - Support for the sparc64-linux-gnu target is now included in
1255 - The amd64-linux build of gdbserver now supports debugging both
1256 32-bit and 64-bit programs.
1258 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1259 now support hardware watchpoints, and will use them automatically
1264 GDB now has support for scripting using Python. Whether this is
1265 available is determined at configure time.
1267 New GDB commands can now be written in Python.
1269 * Ada tasking support
1271 Ada tasks can now be inspected in GDB. The following commands have
1275 Print the list of Ada tasks.
1277 Print detailed information about task number N.
1279 Print the task number of the current task.
1281 Switch the context of debugging to task number N.
1283 * Support for user-defined prefixed commands. The "define" command can
1284 add new commands to existing prefixes, e.g. "target".
1286 * Multi-inferior, multi-process debugging.
1288 GDB now has generalized support for multi-inferior debugging. See
1289 "Debugging Multiple Inferiors" in the manual for more information.
1290 Although availability still depends on target support, the command
1291 set is more uniform now. The GNU/Linux specific multi-forks support
1292 has been migrated to this new framework. This implied some user
1293 visible changes; see "New commands" and also "Removed commands"
1296 * Target descriptions can now describe the target OS ABI. See the
1297 "Target Description Format" section in the user manual for more
1300 * Target descriptions can now describe "compatible" architectures
1301 to indicate that the target can execute applications for a different
1302 architecture in addition to those for the main target architecture.
1303 See the "Target Description Format" section in the user manual for
1306 * Multi-architecture debugging.
1308 GDB now includes general supports for debugging applications on
1309 hybrid systems that use more than one single processor architecture
1310 at the same time. Each such hybrid architecture still requires
1311 specific support to be added. The only hybrid architecture supported
1312 in this version of GDB is the Cell Broadband Engine.
1314 * GDB now supports integrated debugging of Cell/B.E. applications that
1315 use both the PPU and SPU architectures. To enable support for hybrid
1316 Cell/B.E. debugging, you need to configure GDB to support both the
1317 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1318 --enable-targets configure option.
1320 * Non-stop mode debugging.
1322 For some targets, GDB now supports an optional mode of operation in
1323 which you can examine stopped threads while other threads continue
1324 to execute freely. This is referred to as non-stop mode, with the
1325 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1326 section in the user manual for more information.
1328 To be able to support remote non-stop debugging, a remote stub needs
1329 to implement the non-stop mode remote protocol extensions, as
1330 described in the "Remote Non-Stop" section of the user manual. The
1331 GDB remote stub, gdbserver, has been adjusted to support these
1332 extensions on linux targets.
1334 * New commands (for set/show, see "New options" below)
1336 catch syscall [NAME(S) | NUMBER(S)]
1337 Catch system calls. Arguments, which should be names of system
1338 calls or their numbers, mean catch only those syscalls. Without
1339 arguments, every syscall will be caught. When the inferior issues
1340 any of the specified syscalls, GDB will stop and announce the system
1341 call, both when it is called and when its call returns. This
1342 feature is currently available with a native GDB running on the
1343 Linux Kernel, under the following architectures: x86, x86_64,
1344 PowerPC and PowerPC64.
1346 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1348 Search memory for a sequence of bytes.
1350 maint set python print-stack
1351 maint show python print-stack
1352 Show a stack trace when an error is encountered in a Python script.
1355 Invoke CODE by passing it to the Python interpreter.
1360 These allow macros to be defined, undefined, and listed
1364 Show operating system information about processes.
1367 List the inferiors currently under GDB's control.
1370 Switch focus to inferior number NUM.
1373 Detach from inferior number NUM.
1376 Kill inferior number NUM.
1380 set spu stop-on-load
1381 show spu stop-on-load
1382 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1384 set spu auto-flush-cache
1385 show spu auto-flush-cache
1386 Control whether to automatically flush the software-managed cache
1387 during Cell/B.E. debugging.
1389 set sh calling-convention
1390 show sh calling-convention
1391 Control the calling convention used when calling SH target functions.
1394 show debug timestamp
1395 Control display of timestamps with GDB debugging output.
1397 set disassemble-next-line
1398 show disassemble-next-line
1399 Control display of disassembled source lines or instructions when
1402 set remote noack-packet
1403 show remote noack-packet
1404 Set/show the use of remote protocol QStartNoAckMode packet. See above
1405 under "New remote packets."
1407 set remote query-attached-packet
1408 show remote query-attached-packet
1409 Control use of remote protocol `qAttached' (query-attached) packet.
1411 set remote read-siginfo-object
1412 show remote read-siginfo-object
1413 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1416 set remote write-siginfo-object
1417 show remote write-siginfo-object
1418 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1421 set remote reverse-continue
1422 show remote reverse-continue
1423 Control use of remote protocol 'bc' (reverse-continue) packet.
1425 set remote reverse-step
1426 show remote reverse-step
1427 Control use of remote protocol 'bs' (reverse-step) packet.
1429 set displaced-stepping
1430 show displaced-stepping
1431 Control displaced stepping mode. Displaced stepping is a way to
1432 single-step over breakpoints without removing them from the debuggee.
1433 Also known as "out-of-line single-stepping".
1436 show debug displaced
1437 Control display of debugging info for displaced stepping.
1439 maint set internal-error
1440 maint show internal-error
1441 Control what GDB does when an internal error is detected.
1443 maint set internal-warning
1444 maint show internal-warning
1445 Control what GDB does when an internal warning is detected.
1450 Use a wrapper program to launch programs for debugging.
1452 set multiple-symbols (all|ask|cancel)
1453 show multiple-symbols
1454 The value of this variable can be changed to adjust the debugger behavior
1455 when an expression or a breakpoint location contains an ambiguous symbol
1456 name (an overloaded function name, for instance).
1458 set breakpoint always-inserted
1459 show breakpoint always-inserted
1460 Keep breakpoints always inserted in the target, as opposed to inserting
1461 them when resuming the target, and removing them when the target stops.
1462 This option can improve debugger performance on slow remote targets.
1464 set arm fallback-mode (arm|thumb|auto)
1465 show arm fallback-mode
1466 set arm force-mode (arm|thumb|auto)
1468 These commands control how ARM GDB determines whether instructions
1469 are ARM or Thumb. The default for both settings is auto, which uses
1470 the current CPSR value for instructions without symbols; previous
1471 versions of GDB behaved as if "set arm fallback-mode arm".
1473 set disable-randomization
1474 show disable-randomization
1475 Standalone programs run with the virtual address space randomization enabled
1476 by default on some platforms. This option keeps the addresses stable across
1477 multiple debugging sessions.
1481 Control whether other threads are stopped or not when some thread hits
1486 Requests that asynchronous execution is enabled in the target, if available.
1487 In this case, it's possible to resume target in the background, and interact
1488 with GDB while the target is running. "show target-async" displays the
1489 current state of asynchronous execution of the target.
1491 set target-wide-charset
1492 show target-wide-charset
1493 The target-wide-charset is the name of the character set that GDB
1494 uses when printing characters whose type is wchar_t.
1496 set tcp auto-retry (on|off)
1498 set tcp connect-timeout
1499 show tcp connect-timeout
1500 These commands allow GDB to retry failed TCP connections to a remote stub
1501 with a specified timeout period; this is useful if the stub is launched
1502 in parallel with GDB but may not be ready to accept connections immediately.
1504 set libthread-db-search-path
1505 show libthread-db-search-path
1506 Control list of directories which GDB will search for appropriate
1509 set schedule-multiple (on|off)
1510 show schedule-multiple
1511 Allow GDB to resume all threads of all processes or only threads of
1512 the current process.
1516 Use more aggressive caching for accesses to the stack. This improves
1517 performance of remote debugging (particularly backtraces) without
1518 affecting correctness.
1520 set interactive-mode (on|off|auto)
1521 show interactive-mode
1522 Control whether GDB runs in interactive mode (on) or not (off).
1523 When in interactive mode, GDB waits for the user to answer all
1524 queries. Otherwise, GDB does not wait and assumes the default
1525 answer. When set to auto (the default), GDB determines which
1526 mode to use based on the stdin settings.
1531 For program forks, this is replaced by the new more generic `info
1532 inferiors' command. To list checkpoints, you can still use the
1533 `info checkpoints' command, which was an alias for the `info forks'
1537 Replaced by the new `inferior' command. To switch between
1538 checkpoints, you can still use the `restart' command, which was an
1539 alias for the `fork' command.
1542 This is removed, since some targets don't have a notion of
1543 processes. To switch between processes, you can still use the
1544 `inferior' command using GDB's own inferior number.
1547 For program forks, this is replaced by the new more generic `kill
1548 inferior' command. To delete a checkpoint, you can still use the
1549 `delete checkpoint' command, which was an alias for the `delete
1553 For program forks, this is replaced by the new more generic `detach
1554 inferior' command. To detach a checkpoint, you can still use the
1555 `detach checkpoint' command, which was an alias for the `detach
1558 * New native configurations
1560 x86/x86_64 Darwin i[34567]86-*-darwin*
1562 x86_64 MinGW x86_64-*-mingw*
1566 Lattice Mico32 lm32-*
1567 x86 DICOS i[34567]86-*-dicos*
1568 x86_64 DICOS x86_64-*-dicos*
1571 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1572 (mingw32ce) debugging.
1578 These commands were actually not implemented on any target.
1580 *** Changes in GDB 6.8
1582 * New native configurations
1584 NetBSD/hppa hppa*-*netbsd*
1585 Xtensa GNU/Linux xtensa*-*-linux*
1589 NetBSD/hppa hppa*-*-netbsd*
1590 Xtensa GNU/Lunux xtensa*-*-linux*
1592 * Change in command line behavior -- corefiles vs. process ids.
1594 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1595 attaching to process NUMBER fails, GDB no longer attempts to open a
1596 core file named NUMBER. Attaching to a program using the -c option
1597 is no longer supported. Instead, use the '-p' or '--pid' options.
1599 * GDB can now be built as a native debugger for debugging Windows x86
1600 (mingw32) Portable Executable (PE) programs.
1602 * Pending breakpoints no longer change their number when their address
1605 * GDB now supports breakpoints with multiple locations,
1606 including breakpoints on C++ constructors, inside C++ templates,
1607 and in inlined functions.
1609 * GDB's ability to debug optimized code has been improved. GDB more
1610 accurately identifies function bodies and lexical blocks that occupy
1611 more than one contiguous range of addresses.
1613 * Target descriptions can now describe registers for PowerPC.
1615 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1616 registers on PowerPC targets.
1618 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1619 targets even when the libthread_db library is not available.
1621 * The GDB remote stub, gdbserver, now supports the new file transfer
1622 commands (remote put, remote get, and remote delete).
1624 * The GDB remote stub, gdbserver, now supports run and attach in
1625 extended-remote mode.
1627 * hppa*64*-*-hpux11* target broken
1628 The debugger is unable to start a program and fails with the following
1629 error: "Error trying to get information about dynamic linker".
1630 The gdb-6.7 release is also affected.
1632 * GDB now supports the --enable-targets= configure option to allow
1633 building a single GDB executable that supports multiple remote
1634 target architectures.
1636 * GDB now supports debugging C and C++ programs which use the
1637 Decimal Floating Point extension. In addition, the PowerPC target
1638 now has a set of pseudo-registers to inspect decimal float values
1639 stored in two consecutive float registers.
1641 * The -break-insert MI command can optionally create pending
1644 * Improved support for debugging Ada
1645 Many improvements to the Ada language support have been made. These
1647 - Better support for Ada2005 interface types
1648 - Improved handling of arrays and slices in general
1649 - Better support for Taft-amendment types
1650 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1652 - Improved command completion in Ada
1655 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1660 set print frame-arguments (all|scalars|none)
1661 show print frame-arguments
1662 The value of this variable can be changed to control which argument
1663 values should be printed by the debugger when displaying a frame.
1668 Transfer files to and from a remote target, and delete remote files.
1675 Transfer files to and from a remote target, and delete remote files.
1677 * New remote packets
1684 Open, close, read, write, and delete files on the remote system.
1687 Attach to an existing process on the remote system, in extended-remote
1691 Run a new process on the remote system, in extended-remote mode.
1693 *** Changes in GDB 6.7
1695 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1696 bfd, libiberty and opcodes, as revealed by static analysis donated by
1697 Coverity, Inc. (http://scan.coverity.com).
1699 * When looking up multiply-defined global symbols, GDB will now prefer the
1700 symbol definition in the current shared library if it was built using the
1701 -Bsymbolic linker option.
1703 * When the Text User Interface (TUI) is not configured, GDB will now
1704 recognize the -tui command-line option and print a message that the TUI
1707 * The GDB remote stub, gdbserver, now has lower overhead for high
1708 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1710 * GDB for MIPS targets now autodetects whether a remote target provides
1711 32-bit or 64-bit register values.
1713 * Support for C++ member pointers has been improved.
1715 * GDB now understands XML target descriptions, which specify the
1716 target's overall architecture. GDB can read a description from
1717 a local file or over the remote serial protocol.
1719 * Vectors of single-byte data use a new integer type which is not
1720 automatically displayed as character or string data.
1722 * The /s format now works with the print command. It displays
1723 arrays of single-byte integers and pointers to single-byte integers
1726 * Target descriptions can now describe target-specific registers,
1727 for architectures which have implemented the support (currently
1728 only ARM, M68K, and MIPS).
1730 * GDB and the GDB remote stub, gdbserver, now support the XScale
1733 * The GDB remote stub, gdbserver, has been updated to support
1734 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1735 has been rewritten to use the standard GDB remote protocol.
1737 * GDB can now step into C++ functions which are called through thunks.
1739 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1741 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1742 layout. It also supports a TextSeg= and DataSeg= response when only
1743 segment base addresses (rather than offsets) are available.
1745 * The /i format now outputs any trailing branch delay slot instructions
1746 immediately following the last instruction within the count specified.
1748 * The GDB remote protocol "T" stop reply packet now supports a
1749 "library" response. Combined with the new "qXfer:libraries:read"
1750 packet, this response allows GDB to debug shared libraries on targets
1751 where the operating system manages the list of loaded libraries (e.g.
1752 Windows and SymbianOS).
1754 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1755 (DLLs) on Windows and Windows CE targets.
1757 * GDB now supports a faster verification that a .debug file matches its binary
1758 according to its build-id signature, if the signature is present.
1764 Enable or disable hardware flow control (RTS/CTS) on the serial port
1765 when debugging using remote targets.
1767 set mem inaccessible-by-default
1768 show mem inaccessible-by-default
1769 If the target supplies a memory map, for instance via the remote
1770 protocol's "qXfer:memory-map:read" packet, setting this variable
1771 prevents GDB from accessing memory outside the memory map. This
1772 is useful for targets with memory mapped registers or which react
1773 badly to accesses of unmapped address space.
1775 set breakpoint auto-hw
1776 show breakpoint auto-hw
1777 If the target supplies a memory map, for instance via the remote
1778 protocol's "qXfer:memory-map:read" packet, setting this variable
1779 lets GDB use hardware breakpoints automatically for memory regions
1780 where it can not use software breakpoints. This covers both the
1781 "break" command and internal breakpoints used for other commands
1782 including "next" and "finish".
1785 catch exception unhandled
1786 Stop the program execution when Ada exceptions are raised.
1789 Stop the program execution when an Ada assertion failed.
1793 Set an alternate system root for target files. This is a more
1794 general version of "set solib-absolute-prefix", which is now
1795 an alias to "set sysroot".
1798 Provide extended SPU facility status information. This set of
1799 commands is available only when debugging the Cell/B.E. SPU
1802 * New native configurations
1804 OpenBSD/sh sh*-*openbsd*
1807 unset tdesc filename
1809 Use the specified local file as an XML target description, and do
1810 not query the target for its built-in description.
1814 OpenBSD/sh sh*-*-openbsd*
1815 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1816 Toshiba Media Processor mep-elf
1818 * New remote packets
1821 Ignore the specified signals; pass them directly to the debugged program
1822 without stopping other threads or reporting them to GDB.
1824 qXfer:features:read:
1825 Read an XML target description from the target, which describes its
1830 Read or write contents of an spufs file on the target system. These
1831 packets are available only on the Cell/B.E. SPU architecture.
1833 qXfer:libraries:read:
1834 Report the loaded shared libraries. Combined with new "T" packet
1835 response, this packet allows GDB to debug shared libraries on
1836 targets where the operating system manages the list of loaded
1837 libraries (e.g. Windows and SymbianOS).
1841 Support for these obsolete configurations has been removed.
1849 i[34567]86-*-lynxos*
1850 i[34567]86-*-netware*
1851 i[34567]86-*-sco3.2v5*
1852 i[34567]86-*-sco3.2v4*
1854 i[34567]86-*-sysv4.2*
1857 i[34567]86-*-unixware2*
1858 i[34567]86-*-unixware*
1867 * Other removed features
1874 Various m68k-only ROM monitors.
1881 Various Renesas ROM monitors and debugging interfaces for SH and
1886 Support for a Macraigor serial interface to on-chip debugging.
1887 GDB does not directly support the newer parallel or USB
1892 A debug information format. The predecessor to DWARF 2 and
1893 DWARF 3, which are still supported.
1895 Support for the HP aCC compiler on HP-UX/PA-RISC
1897 SOM-encapsulated symbolic debugging information, automatic
1898 invocation of pxdb, and the aCC custom C++ ABI. This does not
1899 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1900 with aCC can still be debugged on an assembly level.
1902 MIPS ".pdr" sections
1904 A MIPS-specific format used to describe stack frame layout
1905 in debugging information.
1909 GDB could work with an older version of Guile to debug
1910 the interpreter and Scheme programs running in it.
1912 set mips stack-arg-size
1913 set mips saved-gpreg-size
1915 Use "set mips abi" to control parameter passing for MIPS.
1917 *** Changes in GDB 6.6
1922 Cell Broadband Engine SPU spu-elf
1924 * GDB can now be configured as a cross-debugger targeting native Windows
1925 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1926 running on a Windows system over TCP/IP to debug Windows programs.
1928 * The GDB remote stub, gdbserver, has been updated to support Windows and
1929 Cygwin debugging. Both single-threaded and multi-threaded programs are
1932 * The "set trust-readonly-sections" command works again. This command was
1933 broken in GDB 6.3, 6.4, and 6.5.
1935 * The "load" command now supports writing to flash memory, if the remote
1936 stub provides the required support.
1938 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1939 longer requires symbolic debug information (e.g. DWARF-2).
1944 unset substitute-path
1945 show substitute-path
1946 Manage a list of substitution rules that GDB uses to rewrite the name
1947 of the directories where the sources are located. This can be useful
1948 for instance when the sources were moved to a different location
1949 between compilation and debugging.
1953 Print each CLI command as it is executed. Each command is prefixed with
1954 a number of `+' symbols representing the nesting depth.
1955 The source command now has a `-v' option to enable the same feature.
1959 The ARM Demon monitor support (RDP protocol, "target rdp").
1961 Kernel Object Display, an embedded debugging feature which only worked with
1962 an obsolete version of Cisco IOS.
1964 The 'set download-write-size' and 'show download-write-size' commands.
1966 * New remote packets
1969 Tell a stub about GDB client features, and request remote target features.
1970 The first feature implemented is PacketSize, which allows the target to
1971 specify the size of packets it can handle - to minimize the number of
1972 packets required and improve performance when connected to a remote
1976 Fetch an OS auxilliary vector from the remote stub. This packet is a
1977 more efficient replacement for qPart:auxv:read.
1979 qXfer:memory-map:read:
1980 Fetch a memory map from the remote stub, including information about
1981 RAM, ROM, and flash memory devices.
1986 Erase and program a flash memory device.
1988 * Removed remote packets
1991 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1992 used it, and only gdbserver implemented it.
1994 *** Changes in GDB 6.5
1998 Renesas M32C/M16C m32c-elf
2000 Morpho Technologies ms1 ms1-elf
2004 init-if-undefined Initialize a convenience variable, but
2005 only if it doesn't already have a value.
2007 The following commands are presently only implemented for native GNU/Linux:
2009 checkpoint Save a snapshot of the program state.
2011 restart <n> Return the program state to a
2012 previously saved state.
2014 info checkpoints List currently saved checkpoints.
2016 delete-checkpoint <n> Delete a previously saved checkpoint.
2018 set|show detach-on-fork Tell gdb whether to detach from a newly
2019 forked process, or to keep debugging it.
2021 info forks List forks of the user program that
2022 are available to be debugged.
2024 fork <n> Switch to debugging one of several
2025 forks of the user program that are
2026 available to be debugged.
2028 delete-fork <n> Delete a fork from the list of forks
2029 that are available to be debugged (and
2030 kill the forked process).
2032 detach-fork <n> Delete a fork from the list of forks
2033 that are available to be debugged (and
2034 allow the process to continue).
2038 Morpho Technologies ms2 ms1-elf
2040 * Improved Windows host support
2042 GDB now builds as a cross debugger hosted on i686-mingw32, including
2043 native console support, and remote communications using either
2044 network sockets or serial ports.
2046 * Improved Modula-2 language support
2048 GDB can now print most types in the Modula-2 syntax. This includes:
2049 basic types, set types, record types, enumerated types, range types,
2050 pointer types and ARRAY types. Procedure var parameters are correctly
2051 printed and hexadecimal addresses and character constants are also
2052 written in the Modula-2 syntax. Best results can be obtained by using
2053 GNU Modula-2 together with the -gdwarf-2 command line option.
2057 The ARM rdi-share module.
2059 The Netware NLM debug server.
2061 *** Changes in GDB 6.4
2063 * New native configurations
2065 OpenBSD/arm arm*-*-openbsd*
2066 OpenBSD/mips64 mips64-*-openbsd*
2070 Morpho Technologies ms1 ms1-elf
2072 * New command line options
2074 --batch-silent As for --batch, but totally silent.
2075 --return-child-result The debugger will exist with the same value
2076 the child (debugged) program exited with.
2077 --eval-command COMMAND, -ex COMMAND
2078 Execute a single GDB CLI command. This may be
2079 specified multiple times and in conjunction
2080 with the --command (-x) option.
2082 * Deprecated commands removed
2084 The following commands, that were deprecated in 2000, have been
2088 set|show arm disassembly-flavor set|show arm disassembler
2089 othernames set arm disassembler
2090 set|show remotedebug set|show debug remote
2091 set|show archdebug set|show debug arch
2092 set|show eventdebug set|show debug event
2095 * New BSD user-level threads support
2097 It is now possible to debug programs using the user-level threads
2098 library on OpenBSD and FreeBSD. Currently supported (target)
2101 FreeBSD/amd64 x86_64-*-freebsd*
2102 FreeBSD/i386 i386-*-freebsd*
2103 OpenBSD/i386 i386-*-openbsd*
2105 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2106 are not yet supported.
2108 * New support for Matsushita MN10300 w/sim added
2109 (Work in progress). mn10300-elf.
2111 * REMOVED configurations and files
2113 VxWorks and the XDR protocol *-*-vxworks
2114 Motorola MCORE mcore-*-*
2115 National Semiconductor NS32000 ns32k-*-*
2117 * New "set print array-indexes" command
2119 After turning this setting "on", GDB prints the index of each element
2120 when displaying arrays. The default is "off" to preserve the previous
2123 * VAX floating point support
2125 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2127 * User-defined command support
2129 In addition to using $arg0..$arg9 for argument passing, it is now possible
2130 to use $argc to determine now many arguments have been passed. See the
2131 section on user-defined commands in the user manual for more information.
2133 *** Changes in GDB 6.3:
2135 * New command line option
2137 GDB now accepts -l followed by a number to set the timeout for remote
2140 * GDB works with GCC -feliminate-dwarf2-dups
2142 GDB now supports a more compact representation of DWARF-2 debug
2143 information using DW_FORM_ref_addr references. These are produced
2144 by GCC with the option -feliminate-dwarf2-dups and also by some
2145 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2146 to use -feliminate-dwarf2-dups.
2148 * Internationalization
2150 When supported by the host system, GDB will be built with
2151 internationalization (libintl). The task of marking up the sources is
2152 continued, we're looking forward to our first translation.
2156 Initial support for debugging programs compiled with the GNAT
2157 implementation of the Ada programming language has been integrated
2158 into GDB. In this release, support is limited to expression evaluation.
2160 * New native configurations
2162 GNU/Linux/m32r m32r-*-linux-gnu
2166 GDB's remote protocol now includes support for the 'p' packet. This
2167 packet is used to fetch individual registers from a remote inferior.
2169 * END-OF-LIFE registers[] compatibility module
2171 GDB's internal register infrastructure has been completely rewritten.
2172 The new infrastructure making possible the implementation of key new
2173 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2176 GDB 6.3 will be the last release to include the the registers[]
2177 compatibility module that allowed out-of-date configurations to
2178 continue to work. This change directly impacts the following
2188 powerpc bdm protocol
2190 Unless there is activity to revive these configurations, they will be
2191 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2193 * OBSOLETE configurations and files
2195 Configurations that have been declared obsolete in this release have
2196 been commented out. Unless there is activity to revive these
2197 configurations, the next release of GDB will have their sources
2198 permanently REMOVED.
2207 *** Changes in GDB 6.2.1:
2209 * MIPS `break main; run' gave an heuristic-fence-post warning
2211 When attempting to run even a simple program, a warning about
2212 heuristic-fence-post being hit would be reported. This problem has
2215 * MIPS IRIX 'long double' crashed GDB
2217 When examining a long double variable, GDB would get a segmentation
2218 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2219 IRIX long double values).
2223 A bug in the VAX stack code was causing problems with the "next"
2224 command. This problem has been fixed.
2226 *** Changes in GDB 6.2:
2228 * Fix for ``many threads''
2230 On GNU/Linux systems that use the NPTL threads library, a program
2231 rapidly creating and deleting threads would confuse GDB leading to the
2234 ptrace: No such process.
2235 thread_db_get_info: cannot get thread info: generic error
2237 This problem has been fixed.
2239 * "-async" and "-noasync" options removed.
2241 Support for the broken "-noasync" option has been removed (it caused
2244 * New ``start'' command.
2246 This command runs the program until the begining of the main procedure.
2248 * New BSD Kernel Data Access Library (libkvm) interface
2250 Using ``target kvm'' it is now possible to debug kernel core dumps and
2251 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2252 platforms. Currently supported (native-only) configurations are:
2254 FreeBSD/amd64 x86_64-*-freebsd*
2255 FreeBSD/i386 i?86-*-freebsd*
2256 NetBSD/i386 i?86-*-netbsd*
2257 NetBSD/m68k m68*-*-netbsd*
2258 NetBSD/sparc sparc-*-netbsd*
2259 OpenBSD/amd64 x86_64-*-openbsd*
2260 OpenBSD/i386 i?86-*-openbsd*
2261 OpenBSD/m68k m68*-openbsd*
2262 OpenBSD/sparc sparc-*-openbsd*
2264 * Signal trampoline code overhauled
2266 Many generic problems with GDB's signal handling code have been fixed.
2267 These include: backtraces through non-contiguous stacks; recognition
2268 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2269 call; backtrace through a signal trampoline; step into and out of
2270 signal handlers; and single-stepping in the signal trampoline.
2272 Please note that kernel bugs are a limiting factor here. These
2273 features have been shown to work on an s390 GNU/Linux system that
2274 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2276 * Cygwin support for DWARF 2 added.
2278 * New native configurations
2280 GNU/Linux/hppa hppa*-*-linux*
2281 OpenBSD/hppa hppa*-*-openbsd*
2282 OpenBSD/m68k m68*-*-openbsd*
2283 OpenBSD/m88k m88*-*-openbsd*
2284 OpenBSD/powerpc powerpc-*-openbsd*
2285 NetBSD/vax vax-*-netbsd*
2286 OpenBSD/vax vax-*-openbsd*
2288 * END-OF-LIFE frame compatibility module
2290 GDB's internal frame infrastructure has been completely rewritten.
2291 The new infrastructure making it possible to support key new features
2292 including DWARF 2 Call Frame Information. To aid in the task of
2293 migrating old configurations to this new infrastructure, a
2294 compatibility module, that allowed old configurations to continue to
2295 work, was also included.
2297 GDB 6.2 will be the last release to include this frame compatibility
2298 module. This change directly impacts the following configurations:
2308 Unless there is activity to revive these configurations, they will be
2309 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2311 * REMOVED configurations and files
2313 Sun 3, running SunOS 3 m68*-*-sunos3*
2314 Sun 3, running SunOS 4 m68*-*-sunos4*
2315 Sun 2, running SunOS 3 m68000-*-sunos3*
2316 Sun 2, running SunOS 4 m68000-*-sunos4*
2317 Motorola 680x0 running LynxOS m68*-*-lynxos*
2318 AT&T 3b1/Unix pc m68*-att-*
2319 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2320 decstation mips-dec-* mips-little-*
2321 riscos mips-*-riscos* mips-*-sysv*
2322 sonymips mips-sony-*
2323 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2325 *** Changes in GDB 6.1.1:
2327 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2329 The TUI (Text-mode User Interface) is now built as part of a default
2330 GDB configuration. It is enabled by either selecting the TUI with the
2331 command line option "-i=tui" or by running the separate "gdbtui"
2332 program. For more information on the TUI, see the manual "Debugging
2335 * Pending breakpoint support (also included in GDB 6.1)
2337 Support has been added to allow you to specify breakpoints in shared
2338 libraries that have not yet been loaded. If a breakpoint location
2339 cannot be found, and the "breakpoint pending" option is set to auto,
2340 GDB queries you if you wish to make the breakpoint pending on a future
2341 shared-library load. If and when GDB resolves the breakpoint symbol,
2342 the pending breakpoint is removed as one or more regular breakpoints
2345 Pending breakpoints are very useful for GCJ Java debugging.
2347 * Fixed ISO-C build problems
2349 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2350 non ISO-C code that stopped them being built using a more strict ISO-C
2351 compiler (e.g., IBM's C compiler).
2353 * Fixed build problem on IRIX 5
2355 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2356 wasn't able to compile compile on an IRIX 5 system.
2358 * Added execute permission to gdb/gdbserver/configure
2360 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2361 permission. This bug would cause configure to fail on a number of
2362 systems (Solaris, IRIX). Ref: server/519.
2364 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2366 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2367 has been updated to use constant array sizes.
2369 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2371 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2372 its generated DWARF Call Frame Info. This encoding was causing GDB to
2373 panic, that panic has been fixed. Ref: gdb/1628.
2375 * Fixed a problem when examining parameters in shared library code.
2377 When examining parameters in optimized shared library code generated
2378 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2379 not available''. GDB now correctly displays the variable's value.
2381 *** Changes in GDB 6.1:
2383 * Removed --with-mmalloc
2385 Support for the mmalloc memory manager has been removed, as it
2386 conflicted with the internal gdb byte cache.
2388 * Changes in AMD64 configurations
2390 The AMD64 target now includes the %cs and %ss registers. As a result
2391 the AMD64 remote protocol has changed; this affects the floating-point
2392 and SSE registers. If you rely on those registers for your debugging,
2393 you should upgrade gdbserver on the remote side.
2395 * Revised SPARC target
2397 The SPARC target has been completely revised, incorporating the
2398 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2399 support for LynxOS and SunOS 4 has been dropped. Calling functions
2400 from within GDB on operating systems with a non-executable stack
2401 (Solaris, OpenBSD) now works.
2405 GDB has a new C++ demangler which does a better job on the mangled
2406 names generated by current versions of g++. It also runs faster, so
2407 with this and other changes gdb should now start faster on large C++
2410 * DWARF 2 Location Expressions
2412 GDB support for location expressions has been extended to support function
2413 arguments and frame bases. Older versions of GDB could crash when they
2416 * C++ nested types and namespaces
2418 GDB's support for nested types and namespaces in C++ has been
2419 improved, especially if you use the DWARF 2 debugging format. (This
2420 is the default for recent versions of GCC on most platforms.)
2421 Specifically, if you have a class "Inner" defined within a class or
2422 namespace "Outer", then GDB realizes that the class's name is
2423 "Outer::Inner", not simply "Inner". This should greatly reduce the
2424 frequency of complaints about not finding RTTI symbols. In addition,
2425 if you are stopped at inside of a function defined within a namespace,
2426 GDB modifies its name lookup accordingly.
2428 * New native configurations
2430 NetBSD/amd64 x86_64-*-netbsd*
2431 OpenBSD/amd64 x86_64-*-openbsd*
2432 OpenBSD/alpha alpha*-*-openbsd*
2433 OpenBSD/sparc sparc-*-openbsd*
2434 OpenBSD/sparc64 sparc64-*-openbsd*
2436 * New debugging protocols
2438 M32R with SDI protocol m32r-*-elf*
2440 * "set prompt-escape-char" command deleted.
2442 The command "set prompt-escape-char" has been deleted. This command,
2443 and its very obscure effet on GDB's prompt, was never documented,
2444 tested, nor mentioned in the NEWS file.
2446 * OBSOLETE configurations and files
2448 Configurations that have been declared obsolete in this release have
2449 been commented out. Unless there is activity to revive these
2450 configurations, the next release of GDB will have their sources
2451 permanently REMOVED.
2453 Sun 3, running SunOS 3 m68*-*-sunos3*
2454 Sun 3, running SunOS 4 m68*-*-sunos4*
2455 Sun 2, running SunOS 3 m68000-*-sunos3*
2456 Sun 2, running SunOS 4 m68000-*-sunos4*
2457 Motorola 680x0 running LynxOS m68*-*-lynxos*
2458 AT&T 3b1/Unix pc m68*-att-*
2459 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2460 decstation mips-dec-* mips-little-*
2461 riscos mips-*-riscos* mips-*-sysv*
2462 sonymips mips-sony-*
2463 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2465 * REMOVED configurations and files
2467 SGI Irix-4.x mips-sgi-irix4 or iris4
2468 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2469 Z8000 simulator z8k-zilog-none or z8ksim
2470 Matsushita MN10200 w/simulator mn10200-*-*
2471 H8/500 simulator h8500-hitachi-hms or h8500hms
2472 HP/PA running BSD hppa*-*-bsd*
2473 HP/PA running OSF/1 hppa*-*-osf*
2474 HP/PA Pro target hppa*-*-pro*
2475 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2476 386BSD i[3456]86-*-bsd*
2477 Sequent family i[3456]86-sequent-sysv4*
2478 i[3456]86-sequent-sysv*
2479 i[3456]86-sequent-bsd*
2480 SPARC running LynxOS sparc-*-lynxos*
2481 SPARC running SunOS 4 sparc-*-sunos4*
2482 Tsqware Sparclet sparclet-*-*
2483 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2485 *** Changes in GDB 6.0:
2489 Support for debugging the Objective-C programming language has been
2490 integrated into GDB.
2492 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2494 DWARF 2's Call Frame Information makes available compiler generated
2495 information that more exactly describes the program's run-time stack.
2496 By using this information, GDB is able to provide more robust stack
2499 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2500 have been updated to use a new backtrace mechanism which includes
2501 DWARF 2 CFI support.
2505 GDB's remote protocol has been extended to include support for hosted
2506 file I/O (where the remote target uses GDB's file system). See GDB's
2507 remote protocol documentation for details.
2509 * All targets using the new architecture framework.
2511 All of GDB's targets have been updated to use the new internal
2512 architecture framework. The way is now open for future GDB releases
2513 to include cross-architecture native debugging support (i386 on amd64,
2516 * GNU/Linux's Thread Local Storage (TLS)
2518 GDB now includes support for for the GNU/Linux implementation of
2519 per-thread variables.
2521 * GNU/Linux's Native POSIX Thread Library (NPTL)
2523 GDB's thread code has been updated to work with either the new
2524 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2526 * Separate debug info.
2528 GDB, in conjunction with BINUTILS, now supports a mechanism for
2529 automatically loading debug information from a separate file. Instead
2530 of shipping full debug and non-debug versions of system libraries,
2531 system integrators can now instead ship just the stripped libraries
2532 and optional debug files.
2534 * DWARF 2 Location Expressions
2536 DWARF 2 Location Expressions allow the compiler to more completely
2537 describe the location of variables (even in optimized code) to the
2540 GDB now includes preliminary support for location expressions (support
2541 for DW_OP_piece is still missing).
2545 A number of long standing bugs that caused GDB to die while starting a
2546 Java application have been fixed. GDB's Java support is now
2547 considered "useable".
2549 * GNU/Linux support for fork, vfork, and exec.
2551 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2552 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2555 * GDB supports logging output to a file
2557 There are two new commands, "set logging" and "show logging", which can be
2558 used to capture GDB's output to a file.
2560 * The meaning of "detach" has changed for gdbserver
2562 The "detach" command will now resume the application, as documented. To
2563 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2566 * d10v, m68hc11 `regs' command deprecated
2568 The `info registers' command has been updated so that it displays the
2569 registers using a format identical to the old `regs' command.
2573 A new command, "maint set profile on/off", has been added. This command can
2574 be used to enable or disable profiling while running GDB, to profile a
2575 session or a set of commands. In addition there is a new configure switch,
2576 "--enable-profiling", which will cause GDB to be compiled with profiling
2577 data, for more informative profiling results.
2579 * Default MI syntax changed to "mi2".
2581 The default MI (machine interface) syntax, enabled by the command line
2582 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2583 "mi1", can be enabled by specifying the option "-i=mi1".
2585 Support for the original "mi0" syntax (included in GDB 5.0) has been
2588 Fix for gdb/192: removed extraneous space when displaying frame level.
2589 Fix for gdb/672: update changelist is now output in mi list format.
2590 Fix for gdb/702: a -var-assign that updates the value now shows up
2591 in a subsequent -var-update.
2593 * New native configurations.
2595 FreeBSD/amd64 x86_64-*-freebsd*
2597 * Multi-arched targets.
2599 HP/PA HPUX11 hppa*-*-hpux*
2600 Renesas M32R/D w/simulator m32r-*-elf*
2602 * OBSOLETE configurations and files
2604 Configurations that have been declared obsolete in this release have
2605 been commented out. Unless there is activity to revive these
2606 configurations, the next release of GDB will have their sources
2607 permanently REMOVED.
2609 Z8000 simulator z8k-zilog-none or z8ksim
2610 Matsushita MN10200 w/simulator mn10200-*-*
2611 H8/500 simulator h8500-hitachi-hms or h8500hms
2612 HP/PA running BSD hppa*-*-bsd*
2613 HP/PA running OSF/1 hppa*-*-osf*
2614 HP/PA Pro target hppa*-*-pro*
2615 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2616 Sequent family i[3456]86-sequent-sysv4*
2617 i[3456]86-sequent-sysv*
2618 i[3456]86-sequent-bsd*
2619 Tsqware Sparclet sparclet-*-*
2620 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2622 * REMOVED configurations and files
2625 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2626 IBM AIX PS/2 i[3456]86-*-aix
2627 i386 running Mach 3.0 i[3456]86-*-mach3*
2628 i386 running Mach i[3456]86-*-mach*
2629 i386 running OSF/1 i[3456]86-*osf1mk*
2630 HP/Apollo 68k Family m68*-apollo*-sysv*,
2632 m68*-hp-bsd*, m68*-hp-hpux*
2633 Argonaut Risc Chip (ARC) arc-*-*
2634 Mitsubishi D30V d30v-*-*
2635 Fujitsu FR30 fr30-*-elf*
2636 OS/9000 i[34]86-*-os9k
2637 I960 with MON960 i960-*-coff
2639 * MIPS $fp behavior changed
2641 The convenience variable $fp, for the MIPS, now consistently returns
2642 the address of the current frame's base. Previously, depending on the
2643 context, $fp could refer to either $sp or the current frame's base
2644 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2645 The GNU Source-Level Debugger''.
2647 *** Changes in GDB 5.3:
2649 * GNU/Linux shared library multi-threaded performance improved.
2651 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2652 `/proc', in preference to `ptrace' for memory reads. This may result
2653 in an improvement in the start-up time of multi-threaded, shared
2654 library applications when run under GDB. One GDB user writes: ``loads
2655 shared libs like mad''.
2657 * ``gdbserver'' now supports multi-threaded applications on some targets
2659 Support for debugging multi-threaded applications which use
2660 the GNU/Linux LinuxThreads package has been added for
2661 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2662 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2664 * GDB now supports C/C++ preprocessor macros.
2666 GDB now expands preprocessor macro invocations in C/C++ expressions,
2667 and provides various commands for showing macro definitions and how
2670 The new command `macro expand EXPRESSION' expands any macro
2671 invocations in expression, and shows the result.
2673 The new command `show macro MACRO-NAME' shows the definition of the
2674 macro named MACRO-NAME, and where it was defined.
2676 Most compilers don't include information about macros in the debugging
2677 information by default. In GCC 3.1, for example, you need to compile
2678 your program with the options `-gdwarf-2 -g3'. If the macro
2679 information is present in the executable, GDB will read it.
2681 * Multi-arched targets.
2683 DEC Alpha (partial) alpha*-*-*
2684 DEC VAX (partial) vax-*-*
2686 National Semiconductor NS32000 (partial) ns32k-*-*
2687 Motorola 68000 (partial) m68k-*-*
2688 Motorola MCORE mcore-*-*
2692 Fujitsu FRV architecture added by Red Hat frv*-*-*
2695 * New native configurations
2697 Alpha NetBSD alpha*-*-netbsd*
2698 SH NetBSD sh*-*-netbsdelf*
2699 MIPS NetBSD mips*-*-netbsd*
2700 UltraSPARC NetBSD sparc64-*-netbsd*
2702 * OBSOLETE configurations and files
2704 Configurations that have been declared obsolete in this release have
2705 been commented out. Unless there is activity to revive these
2706 configurations, the next release of GDB will have their sources
2707 permanently REMOVED.
2709 Mitsubishi D30V d30v-*-*
2710 OS/9000 i[34]86-*-os9k
2711 IBM AIX PS/2 i[3456]86-*-aix
2712 Fujitsu FR30 fr30-*-elf*
2713 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2714 Argonaut Risc Chip (ARC) arc-*-*
2715 i386 running Mach 3.0 i[3456]86-*-mach3*
2716 i386 running Mach i[3456]86-*-mach*
2717 i386 running OSF/1 i[3456]86-*osf1mk*
2718 HP/Apollo 68k Family m68*-apollo*-sysv*,
2720 m68*-hp-bsd*, m68*-hp-hpux*
2721 I960 with MON960 i960-*-coff
2723 * OBSOLETE languages
2725 CHILL, a Pascal like language used by telecommunications companies.
2727 * REMOVED configurations and files
2729 AMD 29k family via UDI a29k-amd-udi, udi29k
2730 A29K VxWorks a29k-*-vxworks
2731 AMD 29000 embedded, using EBMON a29k-none-none
2732 AMD 29000 embedded with COFF a29k-none-coff
2733 AMD 29000 embedded with a.out a29k-none-aout
2735 testsuite/gdb.hp/gdb.threads-hp/ directory
2737 * New command "set max-user-call-depth <nnn>"
2739 This command allows the user to limit the call depth of user-defined
2740 commands. The default is 1024.
2742 * Changes in FreeBSD/i386 native debugging.
2744 Support for the "generate-core-file" has been added.
2746 * New commands "dump", "append", and "restore".
2748 These commands allow data to be copied from target memory
2749 to a bfd-format or binary file (dump and append), and back
2750 from a file into memory (restore).
2752 * Improved "next/step" support on multi-processor Alpha Tru64.
2754 The previous single-step mechanism could cause unpredictable problems,
2755 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2756 of a software single-step mechanism prevents this.
2758 *** Changes in GDB 5.2.1:
2766 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2767 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2768 Fix, by Joel Brobecker imported from mainline.
2770 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2771 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2772 Fix, by Fred Fish, imported from mainline.
2774 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2775 Surprisingly enough, it works now.
2776 By Michal Ludvig, imported from mainline.
2778 i386 hardware watchpoint support:
2779 avoid misses on second run for some targets.
2780 By Pierre Muller, imported from mainline.
2782 *** Changes in GDB 5.2:
2784 * New command "set trust-readonly-sections on[off]".
2786 This command is a hint that tells gdb that read-only sections
2787 really are read-only (ie. that their contents will not change).
2788 In this mode, gdb will go to the object file rather than the
2789 target to read memory from read-only sections (such as ".text").
2790 This can be a significant performance improvement on some
2791 (notably embedded) targets.
2793 * New command "generate-core-file" (or "gcore").
2795 This new gdb command allows the user to drop a core file of the child
2796 process state at any time. So far it's been implemented only for
2797 GNU/Linux and Solaris, but should be relatively easily ported to other
2798 hosts. Argument is core file name (defaults to core.<pid>).
2800 * New command line option
2802 GDB now accepts --pid or -p followed by a process id.
2804 * Change in command line behavior -- corefiles vs. process ids.
2806 There is a subtle behavior in the way in which GDB handles
2807 command line arguments. The first non-flag argument is always
2808 a program to debug, but the second non-flag argument may either
2809 be a corefile or a process id. Previously, GDB would attempt to
2810 open the second argument as a corefile, and if that failed, would
2811 issue a superfluous error message and then attempt to attach it as
2812 a process. Now, if the second argument begins with a non-digit,
2813 it will be treated as a corefile. If it begins with a digit,
2814 GDB will attempt to attach it as a process, and if no such process
2815 is found, will then attempt to open it as a corefile.
2817 * Changes in ARM configurations.
2819 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2820 configuration is fully multi-arch.
2822 * New native configurations
2824 ARM NetBSD arm*-*-netbsd*
2825 x86 OpenBSD i[3456]86-*-openbsd*
2826 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2827 Sparc64 running FreeBSD sparc64-*-freebsd*
2831 Sanyo XStormy16 xstormy16-elf
2833 * OBSOLETE configurations and files
2835 Configurations that have been declared obsolete in this release have
2836 been commented out. Unless there is activity to revive these
2837 configurations, the next release of GDB will have their sources
2838 permanently REMOVED.
2840 AMD 29k family via UDI a29k-amd-udi, udi29k
2841 A29K VxWorks a29k-*-vxworks
2842 AMD 29000 embedded, using EBMON a29k-none-none
2843 AMD 29000 embedded with COFF a29k-none-coff
2844 AMD 29000 embedded with a.out a29k-none-aout
2846 testsuite/gdb.hp/gdb.threads-hp/ directory
2848 * REMOVED configurations and files
2850 TI TMS320C80 tic80-*-*
2852 PowerPC Solaris powerpcle-*-solaris*
2853 PowerPC Windows NT powerpcle-*-cygwin32
2854 PowerPC Netware powerpc-*-netware*
2855 Harris/CXUX m88k m88*-harris-cxux*
2856 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2857 ns32k-utek-sysv* ns32k-utek-*
2858 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2859 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2860 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2861 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2862 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2864 * Changes to command line processing
2866 The new `--args' feature can be used to specify command-line arguments
2867 for the inferior from gdb's command line.
2869 * Changes to key bindings
2871 There is a new `operate-and-get-next' function bound to `C-o'.
2873 *** Changes in GDB 5.1.1
2875 Fix compile problem on DJGPP.
2877 Fix a problem with floating-point registers on the i386 being
2880 Fix to stop GDB crashing on .debug_str debug info.
2882 Numerous documentation fixes.
2884 Numerous testsuite fixes.
2886 *** Changes in GDB 5.1:
2888 * New native configurations
2890 Alpha FreeBSD alpha*-*-freebsd*
2891 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2892 MIPS GNU/Linux mips*-*-linux*
2893 MIPS SGI Irix 6.x mips*-sgi-irix6*
2894 ia64 AIX ia64-*-aix*
2895 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2899 Motorola 68HC11 and 68HC12 m68hc11-elf
2901 UltraSparc running GNU/Linux sparc64-*-linux*
2903 * OBSOLETE configurations and files
2905 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2906 Harris/CXUX m88k m88*-harris-cxux*
2907 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2908 ns32k-utek-sysv* ns32k-utek-*
2909 TI TMS320C80 tic80-*-*
2911 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2912 PowerPC Solaris powerpcle-*-solaris*
2913 PowerPC Windows NT powerpcle-*-cygwin32
2914 PowerPC Netware powerpc-*-netware*
2915 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2916 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2917 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2918 Apple Macintosh (MPW) host N/A
2920 stuff.c (Program to stuff files into a specially prepared space in kdb)
2921 kdb-start.c (Main loop for the standalone kernel debugger)
2923 Configurations that have been declared obsolete in this release have
2924 been commented out. Unless there is activity to revive these
2925 configurations, the next release of GDB will have their sources
2926 permanently REMOVED.
2928 * REMOVED configurations and files
2930 Altos 3068 m68*-altos-*
2931 Convex c1-*-*, c2-*-*
2933 ARM RISCix arm-*-* (as host)
2937 * GDB has been converted to ISO C.
2939 GDB's source code has been converted to ISO C. In particular, the
2940 sources are fully protoized, and rely on standard headers being
2945 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2947 * The MI enabled by default.
2949 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2950 revised and enabled by default. Packages which use GDB as a debugging
2951 engine behind a UI or another front end are encouraged to switch to
2952 using the GDB/MI interface, instead of the old annotations interface
2953 which is now deprecated.
2955 * Support for debugging Pascal programs.
2957 GDB now includes support for debugging Pascal programs. The following
2958 main features are supported:
2960 - Pascal-specific data types such as sets;
2962 - automatic recognition of Pascal sources based on file-name
2965 - Pascal-style display of data types, variables, and functions;
2967 - a Pascal expression parser.
2969 However, some important features are not yet supported.
2971 - Pascal string operations are not supported at all;
2973 - there are some problems with boolean types;
2975 - Pascal type hexadecimal constants are not supported
2976 because they conflict with the internal variables format;
2978 - support for Pascal objects and classes is not full yet;
2980 - unlike Pascal, GDB is case-sensitive for symbol names.
2982 * Changes in completion.
2984 Commands such as `shell', `run' and `set args', which pass arguments
2985 to inferior programs, now complete on file names, similar to what
2986 users expect at the shell prompt.
2988 Commands which accept locations, such as `disassemble', `print',
2989 `breakpoint', `until', etc. now complete on filenames as well as
2990 program symbols. Thus, if you type "break foob TAB", and the source
2991 files linked into the programs include `foobar.c', that file name will
2992 be one of the candidates for completion. However, file names are not
2993 considered for completion after you typed a colon that delimits a file
2994 name from a name of a function in that file, as in "break foo.c:bar".
2996 `set demangle-style' completes on available demangling styles.
2998 * New platform-independent commands:
3000 It is now possible to define a post-hook for a command as well as a
3001 hook that runs before the command. For more details, see the
3002 documentation of `hookpost' in the GDB manual.
3004 * Changes in GNU/Linux native debugging.
3006 Support for debugging multi-threaded programs has been completely
3007 revised for all platforms except m68k and sparc. You can now debug as
3008 many threads as your system allows you to have.
3010 Attach/detach is supported for multi-threaded programs.
3012 Support for SSE registers was added for x86. This doesn't work for
3013 multi-threaded programs though.
3015 * Changes in MIPS configurations.
3017 Multi-arch support is enabled for all MIPS configurations.
3019 GDB can now be built as native debugger on SGI Irix 6.x systems for
3020 debugging n32 executables. (Debugging 64-bit executables is not yet
3023 * Unified support for hardware watchpoints in all x86 configurations.
3025 Most (if not all) native x86 configurations support hardware-assisted
3026 breakpoints and watchpoints in a unified manner. This support
3027 implements debug register sharing between watchpoints, which allows to
3028 put a virtually infinite number of watchpoints on the same address,
3029 and also supports watching regions up to 16 bytes with several debug
3032 The new maintenance command `maintenance show-debug-regs' toggles
3033 debugging print-outs in functions that insert, remove, and test
3034 watchpoints and hardware breakpoints.
3036 * Changes in the DJGPP native configuration.
3038 New command ``info dos sysinfo'' displays assorted information about
3039 the CPU, OS, memory, and DPMI server.
3041 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3042 display information about segment descriptors stored in GDT, LDT, and
3045 New commands ``info dos pde'' and ``info dos pte'' display entries
3046 from Page Directory and Page Tables (for now works with CWSDPMI only).
3047 New command ``info dos address-pte'' displays the Page Table entry for
3048 a given linear address.
3050 GDB can now pass command lines longer than 126 characters to the
3051 program being debugged (requires an update to the libdbg.a library
3052 which is part of the DJGPP development kit).
3054 DWARF2 debug info is now supported.
3056 It is now possible to `step' and `next' through calls to `longjmp'.
3058 * Changes in documentation.
3060 All GDB documentation was converted to GFDL, the GNU Free
3061 Documentation License.
3063 Tracepoints-related commands are now fully documented in the GDB
3066 TUI, the Text-mode User Interface, is now documented in the manual.
3068 Tracepoints-related commands are now fully documented in the GDB
3071 The "GDB Internals" manual now has an index. It also includes
3072 documentation of `ui_out' functions, GDB coding standards, x86
3073 hardware watchpoints, and memory region attributes.
3075 * GDB's version number moved to ``version.in''
3077 The Makefile variable VERSION has been replaced by the file
3078 ``version.in''. People creating GDB distributions should update the
3079 contents of this file.
3083 GUD support is now a standard part of the EMACS distribution.
3085 *** Changes in GDB 5.0:
3087 * Improved support for debugging FP programs on x86 targets
3089 Unified and much-improved support for debugging floating-point
3090 programs on all x86 targets. In particular, ``info float'' now
3091 displays the FP registers in the same format on all x86 targets, with
3092 greater level of detail.
3094 * Improvements and bugfixes in hardware-assisted watchpoints
3096 It is now possible to watch array elements, struct members, and
3097 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3098 on x86 targets no longer erroneously trigger when the address is
3101 * Improvements in the native DJGPP version of GDB
3103 The distribution now includes all the scripts and auxiliary files
3104 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3105 machines ``out of the box''.
3107 The DJGPP version can now debug programs that use signals. It is
3108 possible to catch signals that happened in the debuggee, deliver
3109 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3110 would kill the program being debugged.) Programs that hook hardware
3111 interrupts (keyboard, timer, etc.) can also be debugged.
3113 It is now possible to debug DJGPP programs that redirect their
3114 standard handles or switch them to raw (as opposed to cooked) mode, or
3115 even close them. The command ``run < foo > bar'' works as expected,
3116 and ``info terminal'' reports useful information about the debuggee's
3117 terminal, including raw/cooked mode, redirection, etc.
3119 The DJGPP version now uses termios functions for console I/O, which
3120 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3123 DOS-style file names with drive letters are now fully supported by
3126 It is now possible to debug DJGPP programs that switch their working
3127 directory. It is also possible to rerun the debuggee any number of
3128 times without restarting GDB; thus, you can use the same setup,
3129 breakpoints, etc. for many debugging sessions.
3131 * New native configurations
3133 ARM GNU/Linux arm*-*-linux*
3134 PowerPC GNU/Linux powerpc-*-linux*
3138 Motorola MCore mcore-*-*
3139 x86 VxWorks i[3456]86-*-vxworks*
3140 PowerPC VxWorks powerpc-*-vxworks*
3141 TI TMS320C80 tic80-*-*
3143 * OBSOLETE configurations
3145 Altos 3068 m68*-altos-*
3146 Convex c1-*-*, c2-*-*
3148 ARM RISCix arm-*-* (as host)
3151 Configurations that have been declared obsolete will be commented out,
3152 but the code will be left in place. If there is no activity to revive
3153 these configurations before the next release of GDB, the sources will
3154 be permanently REMOVED.
3156 * Gould support removed
3158 Support for the Gould PowerNode and NP1 has been removed.
3160 * New features for SVR4
3162 On SVR4 native platforms (such as Solaris), if you attach to a process
3163 without first loading a symbol file, GDB will now attempt to locate and
3164 load symbols from the running process's executable file.
3166 * Many C++ enhancements
3168 C++ support has been greatly improved. Overload resolution now works properly
3169 in almost all cases. RTTI support is on the way.
3171 * Remote targets can connect to a sub-program
3173 A popen(3) style serial-device has been added. This device starts a
3174 sub-process (such as a stand-alone simulator) and then communicates
3175 with that. The sub-program to run is specified using the syntax
3176 ``|<program> <args>'' vis:
3178 (gdb) set remotedebug 1
3179 (gdb) target extended-remote |mn10300-elf-sim program-args
3181 * MIPS 64 remote protocol
3183 A long standing bug in the mips64 remote protocol where by GDB
3184 expected certain 32 bit registers (ex SR) to be transfered as 32
3185 instead of 64 bits has been fixed.
3187 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3188 added to provide backward compatibility with older versions of GDB.
3190 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3192 The command ``set remotebinarydownload'' command has been replaced by
3193 ``set remote X-packet''. Other commands in ``set remote'' family
3194 include ``set remote P-packet''.
3196 * Breakpoint commands accept ranges.
3198 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3199 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3200 ``tracepoint passcount'' also accepts a range of tracepoints.
3202 * ``apropos'' command added.
3204 The ``apropos'' command searches through command names and
3205 documentation strings, printing out matches, making it much easier to
3206 try to find a command that does what you are looking for.
3210 A new machine oriented interface (MI) has been added to GDB. This
3211 interface is designed for debug environments running GDB as a separate
3212 process. This is part of the long term libGDB project. See the
3213 "GDB/MI" chapter of the GDB manual for further information. It can be
3214 enabled by configuring with:
3216 .../configure --enable-gdbmi
3218 *** Changes in GDB-4.18:
3220 * New native configurations
3222 HP-UX 10.20 hppa*-*-hpux10.20
3223 HP-UX 11.x hppa*-*-hpux11.0*
3224 M68K GNU/Linux m68*-*-linux*
3228 Fujitsu FR30 fr30-*-elf*
3229 Intel StrongARM strongarm-*-*
3230 Mitsubishi D30V d30v-*-*
3232 * OBSOLETE configurations
3234 Gould PowerNode, NP1 np1-*-*, pn-*-*
3236 Configurations that have been declared obsolete will be commented out,
3237 but the code will be left in place. If there is no activity to revive
3238 these configurations before the next release of GDB, the sources will
3239 be permanently REMOVED.
3243 As a compatibility experiment, GDB's source files buildsym.h and
3244 buildsym.c have been converted to pure standard C, no longer
3245 containing any K&R compatibility code. We believe that all systems in
3246 use today either come with a standard C compiler, or have a GCC port
3247 available. If this is not true, please report the affected
3248 configuration to bug-gdb@gnu.org immediately. See the README file for
3249 information about getting a standard C compiler if you don't have one
3254 GDB now uses readline 2.2.
3256 * set extension-language
3258 You can now control the mapping between filename extensions and source
3259 languages by using the `set extension-language' command. For instance,
3260 you can ask GDB to treat .c files as C++ by saying
3261 set extension-language .c c++
3262 The command `info extensions' lists all of the recognized extensions
3263 and their associated languages.
3265 * Setting processor type for PowerPC and RS/6000
3267 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3268 you can use the `set processor' command to specify what variant of the
3269 PowerPC family you are debugging. The command
3273 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3274 following PowerPC and RS6000 variants:
3276 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3277 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3279 403GC IBM PowerPC 403GC
3280 505 Motorola PowerPC 505
3281 860 Motorola PowerPC 860 or 850
3282 601 Motorola PowerPC 601
3283 602 Motorola PowerPC 602
3284 603 Motorola/IBM PowerPC 603 or 603e
3285 604 Motorola PowerPC 604 or 604e
3286 750 Motorola/IBM PowerPC 750 or 750
3288 At the moment, this command just tells GDB what to name the
3289 special-purpose processor registers. Since almost all the affected
3290 registers are inaccessible to user-level programs, this command is
3291 only useful for remote debugging in its present form.
3295 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3296 more extensive support for HP-UX. Added features include shared
3297 library support, kernel threads and hardware watchpoints for 11.00,
3298 support for HP's ANSI C and C++ compilers, and a compatibility mode
3299 for xdb and dbx commands.
3303 HP's donation includes the new concept of catchpoints, which is a
3304 generalization of the old catch command. On HP-UX, it is now possible
3305 to catch exec, fork, and vfork, as well as library loading.
3307 This means that the existing catch command has changed; its first
3308 argument now specifies the type of catch to be set up. See the
3309 output of "help catch" for a list of catchpoint types.
3311 * Debugging across forks
3313 On HP-UX, you can choose which process to debug when a fork() happens
3318 HP has donated a curses-based terminal user interface (TUI). To get
3319 it, build with --enable-tui. Although this can be enabled for any
3320 configuration, at present it only works for native HP debugging.
3322 * GDB remote protocol additions
3324 A new protocol packet 'X' that writes binary data is now available.
3325 Default behavior is to try 'X', then drop back to 'M' if the stub
3326 fails to respond. The settable variable `remotebinarydownload'
3327 allows explicit control over the use of 'X'.
3329 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3330 full 64-bit address. The command
3332 set remoteaddresssize 32
3334 can be used to revert to the old behaviour. For existing remote stubs
3335 the change should not be noticed, as the additional address information
3338 In order to assist in debugging stubs, you may use the maintenance
3339 command `packet' to send any text string to the stub. For instance,
3341 maint packet heythere
3343 sends the packet "$heythere#<checksum>". Note that it is very easy to
3344 disrupt a debugging session by sending the wrong packet at the wrong
3347 The compare-sections command allows you to compare section data on the
3348 target to what is in the executable file without uploading or
3349 downloading, by comparing CRC checksums.
3351 * Tracing can collect general expressions
3353 You may now collect general expressions at tracepoints. This requires
3354 further additions to the target-side stub; see tracepoint.c and
3355 doc/agentexpr.texi for further details.
3357 * mask-address variable for Mips
3359 For Mips targets, you may control the zeroing of the upper 32 bits of
3360 a 64-bit address by entering `set mask-address on'. This is mainly
3361 of interest to users of embedded R4xxx and R5xxx processors.
3363 * Higher serial baud rates
3365 GDB's serial code now allows you to specify baud rates 57600, 115200,
3366 230400, and 460800 baud. (Note that your host system may not be able
3367 to achieve all of these rates.)
3371 The i960 configuration now includes an initial implementation of a
3372 builtin simulator, contributed by Jim Wilson.
3375 *** Changes in GDB-4.17:
3377 * New native configurations
3379 Alpha GNU/Linux alpha*-*-linux*
3380 Unixware 2.x i[3456]86-unixware2*
3381 Irix 6.x mips*-sgi-irix6*
3382 PowerPC GNU/Linux powerpc-*-linux*
3383 PowerPC Solaris powerpcle-*-solaris*
3384 Sparc GNU/Linux sparc-*-linux*
3385 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3389 Argonaut Risc Chip (ARC) arc-*-*
3390 Hitachi H8/300S h8300*-*-*
3391 Matsushita MN10200 w/simulator mn10200-*-*
3392 Matsushita MN10300 w/simulator mn10300-*-*
3393 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3394 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3395 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3396 Mitsubishi D10V w/simulator d10v-*-*
3397 Mitsubishi M32R/D w/simulator m32r-*-elf*
3398 Tsqware Sparclet sparclet-*-*
3399 NEC V850 w/simulator v850-*-*
3401 * New debugging protocols
3403 ARM with RDI protocol arm*-*-*
3404 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3405 DDB and LSI variants of PMON protocol mips*-*-*
3406 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3407 PowerPC with SDS protocol powerpc{,le}-*-eabi
3408 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3412 All configurations can now understand and use the DWARF 2 debugging
3413 format. The choice is automatic, if the symbol file contains DWARF 2
3418 GDB now includes basic Java language support. This support is
3419 only useful with Java compilers that produce native machine code.
3421 * solib-absolute-prefix and solib-search-path
3423 For SunOS and SVR4 shared libraries, you may now set the prefix for
3424 loading absolute shared library symbol files, and the search path for
3425 locating non-absolute shared library symbol files.
3427 * Live range splitting
3429 GDB can now effectively debug code for which GCC has performed live
3430 range splitting as part of its optimization. See gdb/doc/LRS for
3431 more details on the expected format of the stabs information.
3435 GDB's support for the GNU Hurd, including thread debugging, has been
3436 updated to work with current versions of the Hurd.
3440 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3441 instruction set. ARM GDB automatically detects when Thumb
3442 instructions are in use, and adjusts disassembly and backtracing
3447 GDB's MIPS target configurations now handle the MIP16 16-bit
3452 GDB now includes support for overlays; if an executable has been
3453 linked such that multiple sections are based at the same address, GDB
3454 will decide which section to use for symbolic info. You can choose to
3455 control the decision manually, using overlay commands, or implement
3456 additional target-side support and use "overlay load-target" to bring
3457 in the overlay mapping. Do "help overlay" for more detail.
3461 The command "info symbol <address>" displays information about
3462 the symbol at the specified address.
3466 The standard remote protocol now includes an extension that allows
3467 asynchronous collection and display of trace data. This requires
3468 extensive support in the target-side debugging stub. Tracing mode
3469 includes a new interaction mode in GDB and new commands: see the
3470 file tracepoint.c for more details.
3474 Configurations for embedded MIPS now include a simulator contributed
3475 by Cygnus Solutions. The simulator supports the instruction sets
3476 of most MIPS variants.
3480 Sparc configurations may now include the ERC32 simulator contributed
3481 by the European Space Agency. The simulator is not built into
3482 Sparc targets by default; configure with --enable-sim to include it.
3486 For target configurations that may include multiple variants of a
3487 basic architecture (such as MIPS and SH), you may now set the
3488 architecture explicitly. "set arch" sets, "info arch" lists
3489 the possible architectures.
3491 *** Changes in GDB-4.16:
3493 * New native configurations
3495 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3496 M68K NetBSD m68k-*-netbsd*
3497 PowerPC AIX 4.x powerpc-*-aix*
3498 PowerPC MacOS powerpc-*-macos*
3499 PowerPC Windows NT powerpcle-*-cygwin32
3500 RS/6000 AIX 4.x rs6000-*-aix4*
3504 ARM with RDP protocol arm-*-*
3505 I960 with MON960 i960-*-coff
3506 MIPS VxWorks mips*-*-vxworks*
3507 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3508 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3510 Matra Sparclet sparclet-*-*
3514 The powerpc-eabi configuration now includes the PSIM simulator,
3515 contributed by Andrew Cagney, with assistance from Mike Meissner.
3516 PSIM is a very elaborate model of the PowerPC, including not only
3517 basic instruction set execution, but also details of execution unit
3518 performance and I/O hardware. See sim/ppc/README for more details.
3522 GDB now works with Solaris 2.5.
3524 * Windows 95/NT native
3526 GDB will now work as a native debugger on Windows 95 and Windows NT.
3527 To build it from source, you must use the "gnu-win32" environment,
3528 which uses a DLL to emulate enough of Unix to run the GNU tools.
3529 Further information, binaries, and sources are available at
3530 ftp.cygnus.com, under pub/gnu-win32.
3532 * dont-repeat command
3534 If a user-defined command includes the command `dont-repeat', then the
3535 command will not be repeated if the user just types return. This is
3536 useful if the command is time-consuming to run, so that accidental
3537 extra keystrokes don't run the same command many times.
3539 * Send break instead of ^C
3541 The standard remote protocol now includes an option to send a break
3542 rather than a ^C to the target in order to interrupt it. By default,
3543 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3545 * Remote protocol timeout
3547 The standard remote protocol includes a new variable `remotetimeout'
3548 that allows you to set the number of seconds before GDB gives up trying
3549 to read from the target. The default value is 2.
3551 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3553 By default GDB will automatically keep track of objects as they are
3554 loaded and unloaded by the dynamic linker. By using the command `set
3555 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3556 when shared library events occur, thus allowing you to set breakpoints
3557 in shared libraries which are explicitly loaded by the inferior.
3559 Note this feature does not work on hpux8. On hpux9 you must link
3560 /usr/lib/end.o into your program. This feature should work
3561 automatically on hpux10.
3563 * Irix 5.x hardware watchpoint support
3565 Irix 5 configurations now support the use of hardware watchpoints.
3567 * Mips protocol "SYN garbage limit"
3569 When debugging a Mips target using the `target mips' protocol, you
3570 may set the number of characters that GDB will ignore by setting
3571 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3572 every character. The default value is 1050.
3574 * Recording and replaying remote debug sessions
3576 If you set `remotelogfile' to the name of a file, gdb will write to it
3577 a recording of a remote debug session. This recording may then be
3578 replayed back to gdb using "gdbreplay". See gdbserver/README for
3579 details. This is useful when you have a problem with GDB while doing
3580 remote debugging; you can make a recording of the session and send it
3581 to someone else, who can then recreate the problem.
3583 * Speedups for remote debugging
3585 GDB includes speedups for downloading and stepping MIPS systems using
3586 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3587 and more efficient S-record downloading.
3589 * Memory use reductions and statistics collection
3591 GDB now uses less memory and reports statistics about memory usage.
3592 Try the `maint print statistics' command, for example.
3594 *** Changes in GDB-4.15:
3596 * Psymtabs for XCOFF
3598 The symbol reader for AIX GDB now uses partial symbol tables. This
3599 can greatly improve startup time, especially for large executables.
3601 * Remote targets use caching
3603 Remote targets now use a data cache to speed up communication with the
3604 remote side. The data cache could lead to incorrect results because
3605 it doesn't know about volatile variables, thus making it impossible to
3606 debug targets which use memory mapped I/O devices. `set remotecache
3607 off' turns the the data cache off.
3609 * Remote targets may have threads
3611 The standard remote protocol now includes support for multiple threads
3612 in the target system, using new protocol commands 'H' and 'T'. See
3613 gdb/remote.c for details.
3617 If GDB is configured with `--enable-netrom', then it will include
3618 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3619 acts as though it is a bank of ROM on the target board, but you can
3620 write into it over the network. GDB's support consists only of
3621 support for fast loading into the emulated ROM; to debug, you must use
3622 another protocol, such as standard remote protocol. The usual
3623 sequence is something like
3625 target nrom <netrom-hostname>
3627 target remote <netrom-hostname>:1235
3631 GDB now includes support for the Apple Macintosh, as a host only. It
3632 may be run as either an MPW tool or as a standalone application, and
3633 it can debug through the serial port. All the usual GDB commands are
3634 available, but to the target command, you must supply "serial" as the
3635 device type instead of "/dev/ttyXX". See mpw-README in the main
3636 directory for more information on how to build. The MPW configuration
3637 scripts */mpw-config.in support only a few targets, and only the
3638 mips-idt-ecoff target has been tested.
3642 GDB configuration now uses autoconf. This is not user-visible,
3643 but does simplify configuration and building.
3647 GDB now supports hpux10.
3649 *** Changes in GDB-4.14:
3651 * New native configurations
3653 x86 FreeBSD i[345]86-*-freebsd
3654 x86 NetBSD i[345]86-*-netbsd
3655 NS32k NetBSD ns32k-*-netbsd
3656 Sparc NetBSD sparc-*-netbsd
3660 A29K VxWorks a29k-*-vxworks
3661 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3662 CPU32 EST-300 emulator m68*-*-est*
3663 PowerPC ELF powerpc-*-elf
3666 * Alpha OSF/1 support for procfs
3668 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3669 possible to attach to running processes. As the mounting of the /proc
3670 filesystem is optional on the Alpha, GDB automatically determines
3671 the availability of /proc during startup. This can lead to problems
3672 if /proc is unmounted after GDB has been started.
3674 * Arguments to user-defined commands
3676 User commands may accept up to 10 arguments separated by whitespace.
3677 Arguments are accessed within the user command via $arg0..$arg9. A
3680 print $arg0 + $arg1 + $arg2
3682 To execute the command use:
3685 Defines the command "adder" which prints the sum of its three arguments.
3686 Note the arguments are text substitutions, so they may reference variables,
3687 use complex expressions, or even perform inferior function calls.
3689 * New `if' and `while' commands
3691 This makes it possible to write more sophisticated user-defined
3692 commands. Both commands take a single argument, which is the
3693 expression to evaluate, and must be followed by the commands to
3694 execute, one per line, if the expression is nonzero, the list being
3695 terminated by the word `end'. The `if' command list may include an
3696 `else' word, which causes the following commands to be executed only
3697 if the expression is zero.
3699 * Fortran source language mode
3701 GDB now includes partial support for Fortran 77. It will recognize
3702 Fortran programs and can evaluate a subset of Fortran expressions, but
3703 variables and functions may not be handled correctly. GDB will work
3704 with G77, but does not yet know much about symbols emitted by other
3707 * Better HPUX support
3709 Most debugging facilities now work on dynamic executables for HPPAs
3710 running hpux9 or later. You can attach to running dynamically linked
3711 processes, but by default the dynamic libraries will be read-only, so
3712 for instance you won't be able to put breakpoints in them. To change
3713 that behavior do the following before running the program:
3719 This will cause the libraries to be mapped private and read-write.
3720 To revert to the normal behavior, do this:
3726 You cannot set breakpoints or examine data in the library until after
3727 the library is loaded if the function/data symbols do not have
3730 GDB can now also read debug symbols produced by the HP C compiler on
3731 HPPAs (sorry, no C++, Fortran or 68k support).
3733 * Target byte order now dynamically selectable
3735 You can choose which byte order to use with a target system, via the
3736 commands "set endian big" and "set endian little", and you can see the
3737 current setting by using "show endian". You can also give the command
3738 "set endian auto", in which case GDB will use the byte order
3739 associated with the executable. Currently, only embedded MIPS
3740 configurations support dynamic selection of target byte order.
3742 * New DOS host serial code
3744 This version uses DPMI interrupts to handle buffered I/O, so you
3745 no longer need to run asynctsr when debugging boards connected to
3748 *** Changes in GDB-4.13:
3750 * New "complete" command
3752 This lists all the possible completions for the rest of the line, if it
3753 were to be given as a command itself. This is intended for use by emacs.
3755 * Trailing space optional in prompt
3757 "set prompt" no longer adds a space for you after the prompt you set. This
3758 allows you to set a prompt which ends in a space or one that does not.
3760 * Breakpoint hit counts
3762 "info break" now displays a count of the number of times the breakpoint
3763 has been hit. This is especially useful in conjunction with "ignore"; you
3764 can ignore a large number of breakpoint hits, look at the breakpoint info
3765 to see how many times the breakpoint was hit, then run again, ignoring one
3766 less than that number, and this will get you quickly to the last hit of
3769 * Ability to stop printing at NULL character
3771 "set print null-stop" will cause GDB to stop printing the characters of
3772 an array when the first NULL is encountered. This is useful when large
3773 arrays actually contain only short strings.
3775 * Shared library breakpoints
3777 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3778 breakpoints in shared libraries before the executable is run.
3780 * Hardware watchpoints
3782 There is a new hardware breakpoint for the watch command for sparclite
3783 targets. See gdb/sparclite/hw_breakpoint.note.
3785 Hardware watchpoints are also now supported under GNU/Linux.
3789 Annotations have been added. These are for use with graphical interfaces,
3790 and are still experimental. Currently only gdba.el uses these.
3792 * Improved Irix 5 support
3794 GDB now works properly with Irix 5.2.
3796 * Improved HPPA support
3798 GDB now works properly with the latest GCC and GAS.
3800 * New native configurations
3802 Sequent PTX4 i[34]86-sequent-ptx4
3803 HPPA running OSF/1 hppa*-*-osf*
3804 Atari TT running SVR4 m68*-*-sysv4*
3805 RS/6000 LynxOS rs6000-*-lynxos*
3809 OS/9000 i[34]86-*-os9k
3810 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3813 * Hitachi SH7000 and E7000-PC ICE support
3815 There is now support for communicating with the Hitachi E7000-PC ICE.
3816 This is available automatically when GDB is configured for the SH.
3820 As usual, a variety of small fixes and improvements, both generic
3821 and configuration-specific. See the ChangeLog for more detail.
3823 *** Changes in GDB-4.12:
3825 * Irix 5 is now supported
3829 GDB-4.12 on the HPPA has a number of changes which make it unable
3830 to debug the output from the currently released versions of GCC and
3831 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3832 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3833 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3836 *** Changes in GDB-4.11:
3838 * User visible changes:
3842 The "set remotedebug" option is now consistent between the mips remote
3843 target, remote targets using the gdb-specific protocol, UDI (AMD's
3844 debug protocol for the 29k) and the 88k bug monitor. It is now an
3845 integer specifying a debug level (normally 0 or 1, but 2 means more
3846 debugging info for the mips target).
3848 * DEC Alpha native support
3850 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3851 debug info, but GDB works fairly well with the DEC compiler and should
3852 work with a future GCC release. See the README file for a few
3853 Alpha-specific notes.
3855 * Preliminary thread implementation
3857 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3859 * LynxOS native and target support for 386
3861 This release has been hosted on LynxOS 2.2, and also can be configured
3862 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3865 * Improvements in C++ mangling/demangling.
3867 This release has much better g++ debugging, specifically in name
3868 mangling/demangling, virtual function calls, print virtual table,
3869 call methods, ...etc.
3871 *** Changes in GDB-4.10:
3873 * User visible changes:
3875 Remote debugging using the GDB-specific (`target remote') protocol now
3876 supports the `load' command. This is only useful if you have some
3877 other way of getting the stub to the target system, and you can put it
3878 somewhere in memory where it won't get clobbered by the download.
3880 Filename completion now works.
3882 When run under emacs mode, the "info line" command now causes the
3883 arrow to point to the line specified. Also, "info line" prints
3884 addresses in symbolic form (as well as hex).
3886 All vxworks based targets now support a user settable option, called
3887 vxworks-timeout. This option represents the number of seconds gdb
3888 should wait for responses to rpc's. You might want to use this if
3889 your vxworks target is, perhaps, a slow software simulator or happens
3890 to be on the far side of a thin network line.
3894 This release contains support for using a DEC alpha as a GDB host for
3895 cross debugging. Native alpha debugging is not supported yet.
3898 *** Changes in GDB-4.9:
3902 This is the first GDB release which is accompanied by a matching testsuite.
3903 The testsuite requires installation of dejagnu, which should be available
3904 via ftp from most sites that carry GNU software.
3908 'Cfront' style demangling has had its name changed to 'ARM' style, to
3909 emphasize that it was written from the specifications in the C++ Annotated
3910 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3911 disclaimers, it still generated too much confusion with users attempting to
3912 use gdb with AT&T cfront.
3916 GDB now uses a standard remote interface to a simulator library.
3917 So far, the library contains simulators for the Zilog Z8001/2, the
3918 Hitachi H8/300, H8/500 and Super-H.
3920 * New targets supported
3922 H8/300 simulator h8300-hitachi-hms or h8300hms
3923 H8/500 simulator h8500-hitachi-hms or h8500hms
3924 SH simulator sh-hitachi-hms or sh
3925 Z8000 simulator z8k-zilog-none or z8ksim
3926 IDT MIPS board over serial line mips-idt-ecoff
3928 Cross-debugging to GO32 targets is supported. It requires a custom
3929 version of the i386-stub.c module which is integrated with the
3930 GO32 memory extender.
3932 * New remote protocols
3934 MIPS remote debugging protocol.
3936 * New source languages supported
3938 This version includes preliminary support for Chill, a Pascal like language
3939 used by telecommunications companies. Chill support is also being integrated
3940 into the GNU compiler, but we don't know when it will be publically available.
3943 *** Changes in GDB-4.8:
3945 * HP Precision Architecture supported
3947 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3948 version of this support was available as a set of patches from the
3949 University of Utah. GDB does not support debugging of programs
3950 compiled with the HP compiler, because HP will not document their file
3951 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3952 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3954 Many problems in the preliminary version have been fixed.
3956 * Faster and better demangling
3958 We have improved template demangling and fixed numerous bugs in the GNU style
3959 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3960 character types (wchar_t) are now supported. Demangling of each symbol is now
3961 only done once, and is cached when the symbol table for a file is read in.
3962 This results in a small increase in memory usage for C programs, a moderate
3963 increase in memory usage for C++ programs, and a fantastic speedup in
3966 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3967 from the specifications in the Annotated Reference Manual, which AT&T's
3968 compiler does not actually implement.
3970 * G++ multiple inheritance compiler problem
3972 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3973 inheritance lattices was reworked to properly discover ambiguities. We
3974 recently found an example which causes this new algorithm to fail in a
3975 very subtle way, producing bad debug information for those classes.
3976 The file 'gcc.patch' (in this directory) can be applied to gcc to
3977 circumvent the problem. A future GCC release will contain a complete
3980 The previous G++ debug info problem (mentioned below for the gdb-4.7
3981 release) is fixed in gcc version 2.3.2.
3983 * Improved configure script
3985 The `configure' script will now attempt to guess your system type if
3986 you don't supply a host system type. The old scheme of supplying a
3987 host system triplet is preferable over using this. All the magic is
3988 done in the new `config.guess' script. Examine it for details.
3990 We have also brought our configure script much more in line with the FSF's
3991 version. It now supports the --with-xxx options. In particular,
3992 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3993 The resulting GDB will not be able to read arbitrary object file formats --
3994 only the format ``expected'' to be used on the configured target system.
3995 We hope to make this the default in a future release.
3997 * Documentation improvements
3999 There's new internal documentation on how to modify GDB, and how to
4000 produce clean changes to the code. We implore people to read it
4001 before submitting changes.
4003 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4004 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4005 `info' files are also provided. To build `info' files from scratch,
4006 you will need the latest `makeinfo' release, which will be available in
4007 a future texinfo-X.Y release.
4009 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4010 We're not sure exactly which versions have this problem, but it has
4011 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4012 or better. If that isn't possible, there is a patch in
4013 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4014 around this problem.
4018 GDB now supports array constants that can be used in expressions typed in by
4019 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4020 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4023 The new directory `gdb/sparclite' contains a program that demonstrates
4024 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4026 * New native hosts supported
4028 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4029 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4031 * New targets supported
4033 AMD 29k family via UDI a29k-amd-udi or udi29k
4035 * New file formats supported
4037 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4038 HPUX core files, and SCO 3.2v2 core files.
4042 Attaching to processes now works again; thanks for the many bug reports.
4044 We have also stomped on a bunch of core dumps caused by
4045 printf_filtered("%s") problems.
4047 We eliminated a copyright problem on the rpc and ptrace header files
4048 for VxWorks, which was discovered at the last minute during the 4.7
4049 release. You should now be able to build a VxWorks GDB.
4051 You can now interrupt gdb while an attached process is running. This
4052 will cause the attached process to stop, and give control back to GDB.
4054 We fixed problems caused by using too many file descriptors
4055 for reading symbols from object files and libraries. This was
4056 especially a problem for programs that used many (~100) shared
4059 The `step' command now only enters a subroutine if there is line number
4060 information for the subroutine. Otherwise it acts like the `next'
4061 command. Previously, `step' would enter subroutines if there was
4062 any debugging information about the routine. This avoids problems
4063 when using `cc -g1' on MIPS machines.
4065 * Internal improvements
4067 GDB's internal interfaces have been improved to make it easier to support
4068 debugging of multiple languages in the future.
4070 GDB now uses a common structure for symbol information internally.
4071 Minimal symbols (derived from linkage symbols in object files), partial
4072 symbols (from a quick scan of debug information), and full symbols
4073 contain a common subset of information, making it easier to write
4074 shared code that handles any of them.
4076 * New command line options
4078 We now accept --silent as an alias for --quiet.
4082 The memory-mapped-malloc library is now licensed under the GNU Library
4083 General Public License.
4085 *** Changes in GDB-4.7:
4087 * Host/native/target split
4089 GDB has had some major internal surgery to untangle the support for
4090 hosts and remote targets. Now, when you configure GDB for a remote
4091 target, it will no longer load in all of the support for debugging
4092 local programs on the host. When fully completed and tested, this will
4093 ensure that arbitrary host/target combinations are possible.
4095 The primary conceptual shift is to separate the non-portable code in
4096 GDB into three categories. Host specific code is required any time GDB
4097 is compiled on that host, regardless of the target. Target specific
4098 code relates to the peculiarities of the target, but can be compiled on
4099 any host. Native specific code is everything else: it can only be
4100 built when the host and target are the same system. Child process
4101 handling and core file support are two common `native' examples.
4103 GDB's use of /proc for controlling Unix child processes is now cleaner.
4104 It has been split out into a single module under the `target_ops' vector,
4105 plus two native-dependent functions for each system that uses /proc.
4107 * New hosts supported
4109 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4110 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4111 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4113 * New targets supported
4115 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4116 68030 and CPU32 m68030-*-*, m68332-*-*
4118 * New native hosts supported
4120 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4121 (386bsd is not well tested yet)
4122 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4124 * New file formats supported
4126 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4127 supports reading of `a.out.adobe' object files, which are an a.out
4128 format extended with minimal information about multiple sections.
4132 `show copying' is the same as the old `info copying'.
4133 `show warranty' is the same as `info warrantee'.
4134 These were renamed for consistency. The old commands continue to work.
4136 `info handle' is a new alias for `info signals'.
4138 You can now define pre-command hooks, which attach arbitrary command
4139 scripts to any command. The commands in the hook will be executed
4140 prior to the user's command. You can also create a hook which will be
4141 executed whenever the program stops. See gdb.texinfo.
4145 We now deal with Cfront style name mangling, and can even extract type
4146 info from mangled symbols. GDB can automatically figure out which
4147 symbol mangling style your C++ compiler uses.
4149 Calling of methods and virtual functions has been improved as well.
4153 The crash that occured when debugging Sun Ansi-C compiled binaries is
4154 fixed. This was due to mishandling of the extra N_SO stabs output
4157 We also finally got Ultrix 4.2 running in house, and fixed core file
4158 support, with help from a dozen people on the net.
4160 John M. Farrell discovered that the reason that single-stepping was so
4161 slow on all of the Mips based platforms (primarily SGI and DEC) was
4162 that we were trying to demangle and lookup a symbol used for internal
4163 purposes on every instruction that was being stepped through. Changing
4164 the name of that symbol so that it couldn't be mistaken for a C++
4165 mangled symbol sped things up a great deal.
4167 Rich Pixley sped up symbol lookups in general by getting much smarter
4168 about when C++ symbol mangling is necessary. This should make symbol
4169 completion (TAB on the command line) much faster. It's not as fast as
4170 we'd like, but it's significantly faster than gdb-4.6.
4174 A new user controllable variable 'call_scratch_address' can
4175 specify the location of a scratch area to be used when GDB
4176 calls a function in the target. This is necessary because the
4177 usual method of putting the scratch area on the stack does not work
4178 in systems that have separate instruction and data spaces.
4180 We integrated changes to support the 29k UDI (Universal Debugger
4181 Interface), but discovered at the last minute that we didn't have all
4182 of the appropriate copyright paperwork. We are working with AMD to
4183 resolve this, and hope to have it available soon.
4187 We have sped up the remote serial line protocol, especially for targets
4188 with lots of registers. It now supports a new `expedited status' ('T')
4189 message which can be used in place of the existing 'S' status message.
4190 This allows the remote stub to send only the registers that GDB
4191 needs to make a quick decision about single-stepping or conditional
4192 breakpoints, eliminating the need to fetch the entire register set for
4193 each instruction being stepped through.
4195 The GDB remote serial protocol now implements a write-through cache for
4196 registers, only re-reading the registers if the target has run.
4198 There is also a new remote serial stub for SPARC processors. You can
4199 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4200 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4201 processor with a serial port.
4205 Configure.in files have become much easier to read and modify. A new
4206 `table driven' format makes it more obvious what configurations are
4207 supported, and what files each one uses.
4211 There is a new opcodes library which will eventually contain all of the
4212 disassembly routines and opcode tables. At present, it only contains
4213 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4214 disassembler (binutils/objdump) to share these routines.
4216 The libiberty library is now copylefted under the GNU Library General
4217 Public License. This allows more liberal use, and was done so libg++
4218 can use it. This makes no difference to GDB, since the Library License
4219 grants all the rights from the General Public License.
4223 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4224 reference to the stabs symbol info used by the debugger. It is (as far
4225 as we know) the only published document on this fascinating topic. We
4226 encourage you to read it, compare it to the stabs information on your
4227 system, and send improvements on the document in general (to
4228 bug-gdb@prep.ai.mit.edu).
4230 And, of course, many bugs have been fixed.
4233 *** Changes in GDB-4.6:
4235 * Better support for C++ function names
4237 GDB now accepts as input the "demangled form" of C++ overloaded function
4238 names and member function names, and can do command completion on such names
4239 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4240 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4241 Make use of command completion, it is your friend.
4243 GDB also now accepts a variety of C++ mangled symbol formats. They are
4244 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4245 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4246 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4247 for the list of formats.
4249 * G++ symbol mangling problem
4251 Recent versions of gcc have a bug in how they emit debugging information for
4252 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4253 directory) can be applied to gcc to fix the problem. Alternatively, if you
4254 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4255 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4256 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4259 * New 'maintenance' command
4261 All of the commands related to hacking GDB internals have been moved out of
4262 the main command set, and now live behind the 'maintenance' command. This
4263 can also be abbreviated as 'mt'. The following changes were made:
4265 dump-me -> maintenance dump-me
4266 info all-breakpoints -> maintenance info breakpoints
4267 printmsyms -> maintenance print msyms
4268 printobjfiles -> maintenance print objfiles
4269 printpsyms -> maintenance print psymbols
4270 printsyms -> maintenance print symbols
4272 The following commands are new:
4274 maintenance demangle Call internal GDB demangler routine to
4275 demangle a C++ link name and prints the result.
4276 maintenance print type Print a type chain for a given symbol
4278 * Change to .gdbinit file processing
4280 We now read the $HOME/.gdbinit file before processing the argv arguments
4281 (e.g. reading symbol files or core files). This allows global parameters to
4282 be set, which will apply during the symbol reading. The ./.gdbinit is still
4283 read after argv processing.
4285 * New hosts supported
4287 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4289 GNU/Linux support i386-unknown-linux or linux
4291 We are also including code to support the HP/PA running BSD and HPUX. This
4292 is almost guaranteed not to work, as we didn't have time to test or build it
4293 for this release. We are including it so that the more adventurous (or
4294 masochistic) of you can play with it. We also had major problems with the
4295 fact that the compiler that we got from HP doesn't support the -g option.
4298 * New targets supported
4300 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4302 * More smarts about finding #include files
4304 GDB now remembers the compilation directory for all include files, and for
4305 all files from which C is generated (like yacc and lex sources). This
4306 greatly improves GDB's ability to find yacc/lex sources, and include files,
4307 especially if you are debugging your program from a directory different from
4308 the one that contains your sources.
4310 We also fixed a bug which caused difficulty with listing and setting
4311 breakpoints in include files which contain C code. (In the past, you had to
4312 try twice in order to list an include file that you hadn't looked at before.)
4314 * Interesting infernals change
4316 GDB now deals with arbitrary numbers of sections, where the symbols for each
4317 section must be relocated relative to that section's landing place in the
4318 target's address space. This work was needed to support ELF with embedded
4319 stabs used by Solaris-2.0.
4321 * Bug fixes (of course!)
4323 There have been loads of fixes for the following things:
4324 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4325 i960, stabs, DOS(GO32), procfs, etc...
4327 See the ChangeLog for details.
4329 *** Changes in GDB-4.5:
4331 * New machines supported (host and target)
4333 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4335 SGI Irix-4.x mips-sgi-irix4 or iris4
4337 * New malloc package
4339 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4340 Mmalloc is capable of handling mutiple heaps of memory. It is also
4341 capable of saving a heap to a file, and then mapping it back in later.
4342 This can be used to greatly speedup the startup of GDB by using a
4343 pre-parsed symbol table which lives in a mmalloc managed heap. For
4344 more details, please read mmalloc/mmalloc.texi.
4348 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4349 'help info proc' for details.
4351 * MIPS ecoff symbol table format
4353 The code that reads MIPS symbol table format is now supported on all hosts.
4354 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4357 * File name changes for MS-DOS
4359 Many files in the config directories have been renamed to make it easier to
4360 support GDB on MS-DOSe systems (which have very restrictive file name
4361 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4362 environment) is close to working but has some remaining problems. Note
4363 that debugging of DOS programs is not supported, due to limitations
4364 in the ``operating system'', but it can be used to host cross-debugging.
4366 * Cross byte order fixes
4368 Many fixes have been made to support cross debugging of Sparc and MIPS
4369 targets from hosts whose byte order differs.
4371 * New -mapped and -readnow options
4373 If memory-mapped files are available on your system through the 'mmap'
4374 system call, you can use the -mapped option on the `file' or
4375 `symbol-file' commands to cause GDB to write the symbols from your
4376 program into a reusable file. If the program you are debugging is
4377 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4378 Future GDB debugging sessions will notice the presence of this file,
4379 and will quickly map in symbol information from it, rather than reading
4380 the symbol table from the executable program. Using the '-mapped'
4381 option in a GDB `file' or `symbol-file' command has the same effect as
4382 starting GDB with the '-mapped' command-line option.
4384 You can cause GDB to read the entire symbol table immediately by using
4385 the '-readnow' option with any of the commands that load symbol table
4386 information (or on the GDB command line). This makes the command
4387 slower, but makes future operations faster.
4389 The -mapped and -readnow options are typically combined in order to
4390 build a `fred.syms' file that contains complete symbol information.
4391 A simple GDB invocation to do nothing but build a `.syms' file for future
4394 gdb -batch -nx -mapped -readnow programname
4396 The `.syms' file is specific to the host machine on which GDB is run.
4397 It holds an exact image of GDB's internal symbol table. It cannot be
4398 shared across multiple host platforms.
4400 * longjmp() handling
4402 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4403 siglongjmp() without losing control. This feature has not yet been ported to
4404 all systems. It currently works on many 386 platforms, all MIPS-based
4405 platforms (SGI, DECstation, etc), and Sun3/4.
4409 Preliminary work has been put in to support the new Solaris OS from Sun. At
4410 this time, it can control and debug processes, but it is not capable of
4415 As always, many many bug fixes. The major areas were with g++, and mipsread.
4416 People using the MIPS-based platforms should experience fewer mysterious
4417 crashes and trashed symbol tables.
4419 *** Changes in GDB-4.4:
4421 * New machines supported (host and target)
4423 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4425 BSD Reno on Vax vax-dec-bsd
4426 Ultrix on Vax vax-dec-ultrix
4428 * New machines supported (target)
4430 AMD 29000 embedded, using EBMON a29k-none-none
4434 GDB continues to improve its handling of C++. `References' work better.
4435 The demangler has also been improved, and now deals with symbols mangled as
4436 per the Annotated C++ Reference Guide.
4438 GDB also now handles `stabs' symbol information embedded in MIPS
4439 `ecoff' symbol tables. Since the ecoff format was not easily
4440 extensible to handle new languages such as C++, this appeared to be a
4441 good way to put C++ debugging info into MIPS binaries. This option
4442 will be supported in the GNU C compiler, version 2, when it is
4445 * New features for SVR4
4447 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4448 shared libraries. Debugging dynamically linked programs should present
4449 only minor differences from debugging statically linked programs.
4451 The `info proc' command will print out information about any process
4452 on an SVR4 system (including the one you are debugging). At the moment,
4453 it prints the address mappings of the process.
4455 If you bring up GDB on another SVR4 system, please send mail to
4456 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4458 * Better dynamic linking support in SunOS
4460 Reading symbols from shared libraries which contain debugging symbols
4461 now works properly. However, there remain issues such as automatic
4462 skipping of `transfer vector' code during function calls, which
4463 make it harder to debug code in a shared library, than to debug the
4464 same code linked statically.
4468 GDB is now using the latest `getopt' routines from the FSF. This
4469 version accepts the -- prefix for options with long names. GDB will
4470 continue to accept the old forms (-option and +option) as well.
4471 Various single letter abbreviations for options have been explicity
4472 added to the option table so that they won't get overshadowed in the
4473 future by other options that begin with the same letter.
4477 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4478 Many assorted bugs have been handled. Many more remain to be handled.
4479 See the various ChangeLog files (primarily in gdb and bfd) for details.
4482 *** Changes in GDB-4.3:
4484 * New machines supported (host and target)
4486 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4487 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4488 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4490 * Almost SCO Unix support
4492 We had hoped to support:
4493 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4494 (except for core file support), but we discovered very late in the release
4495 that it has problems with process groups that render gdb unusable. Sorry
4496 about that. I encourage people to fix it and post the fixes.
4498 * Preliminary ELF and DWARF support
4500 GDB can read ELF object files on System V Release 4, and can handle
4501 debugging records for C, in DWARF format, in ELF files. This support
4502 is preliminary. If you bring up GDB on another SVR4 system, please
4503 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4508 GDB now uses the latest `readline' library. One user-visible change
4509 is that two tabs will list possible command completions, which previously
4510 required typing M-? (meta-question mark, or ESC ?).
4514 The `stepi' bug that many of you noticed has been squashed.
4515 Many bugs in C++ have been handled. Many more remain to be handled.
4516 See the various ChangeLog files (primarily in gdb and bfd) for details.
4518 * State of the MIPS world (in case you wondered):
4520 GDB can understand the symbol tables emitted by the compilers
4521 supplied by most vendors of MIPS-based machines, including DEC. These
4522 symbol tables are in a format that essentially nobody else uses.
4524 Some versions of gcc come with an assembler post-processor called
4525 mips-tfile. This program is required if you want to do source-level
4526 debugging of gcc-compiled programs. I believe FSF does not ship
4527 mips-tfile with gcc version 1, but it will eventually come with gcc
4530 Debugging of g++ output remains a problem. g++ version 1.xx does not
4531 really support it at all. (If you're lucky, you should be able to get
4532 line numbers and stack traces to work, but no parameters or local
4533 variables.) With some work it should be possible to improve the
4536 When gcc version 2 is released, you will have somewhat better luck.
4537 However, even then you will get confusing results for inheritance and
4540 We will eventually provide full debugging of g++ output on
4541 DECstations. This will probably involve some kind of stabs-in-ecoff
4542 encapulation, but the details have not been worked out yet.
4545 *** Changes in GDB-4.2:
4547 * Improved configuration
4549 Only one copy of `configure' exists now, and it is not self-modifying.
4550 Porting BFD is simpler.
4554 The `step' and `next' commands now only stop at the first instruction
4555 of a source line. This prevents the multiple stops that used to occur
4556 in switch statements, for-loops, etc. `Step' continues to stop if a
4557 function that has debugging information is called within the line.
4561 Lots of small bugs fixed. More remain.
4563 * New host supported (not target)
4565 Intel 386 PC clone running Mach i386-none-mach
4568 *** Changes in GDB-4.1:
4570 * Multiple source language support
4572 GDB now has internal scaffolding to handle several source languages.
4573 It determines the type of each source file from its filename extension,
4574 and will switch expression parsing and number formatting to match the
4575 language of the function in the currently selected stack frame.
4576 You can also specifically set the language to be used, with
4577 `set language c' or `set language modula-2'.
4581 GDB now has preliminary support for the GNU Modula-2 compiler,
4582 currently under development at the State University of New York at
4583 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4584 continue through the fall of 1991 and into 1992.
4586 Other Modula-2 compilers are currently not supported, and attempting to
4587 debug programs compiled with them will likely result in an error as the
4588 symbol table is read. Feel free to work on it, though!
4590 There are hooks in GDB for strict type checking and range checking,
4591 in the `Modula-2 philosophy', but they do not currently work.
4595 GDB can now write to executable and core files (e.g. patch
4596 a variable's value). You must turn this switch on, specify
4597 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4598 by assigning a new value to a variable. Modifications take
4601 * Automatic SunOS shared library reading
4603 When you run your program, GDB automatically determines where its
4604 shared libraries (if any) have been loaded, and reads their symbols.
4605 The `share' command is no longer needed. This also works when
4606 examining core files.
4610 You can specify the number of lines that the `list' command shows.
4613 * New machines supported (host and target)
4615 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4616 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4617 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4619 * New hosts supported (not targets)
4621 IBM RT/PC: romp-ibm-aix or rtpc
4623 * New targets supported (not hosts)
4625 AMD 29000 embedded with COFF a29k-none-coff
4626 AMD 29000 embedded with a.out a29k-none-aout
4627 Ultracomputer remote kernel debug a29k-nyu-kern
4629 * New remote interfaces
4635 *** Changes in GDB-4.0:
4639 Wide output is wrapped at good places to make the output more readable.
4641 Gdb now supports cross-debugging from a host machine of one type to a
4642 target machine of another type. Communication with the target system
4643 is over serial lines. The ``target'' command handles connecting to the
4644 remote system; the ``load'' command will download a program into the
4645 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4646 also supports debugging of realtime processes running under VxWorks,
4647 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4648 stub on the target system.
4650 New CPUs supported include the AMD 29000 and Intel 960.
4652 GDB now reads object files and symbol tables via a ``binary file''
4653 library, which allows a single copy of GDB to debug programs of multiple
4654 object file types such as a.out and coff.
4656 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4657 refcard.dvi and refcard.ps are available to format it).
4660 * Control-Variable user interface simplified
4662 All variables that control the operation of the debugger can be set
4663 by the ``set'' command, and displayed by the ``show'' command.
4665 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4666 ``Show prompt'' produces the response:
4667 Gdb's prompt is new-gdb=>.
4669 What follows are the NEW set commands. The command ``help set'' will
4670 print a complete list of old and new set commands. ``help set FOO''
4671 will give a longer description of the variable FOO. ``show'' will show
4672 all of the variable descriptions and their current settings.
4674 confirm on/off: Enables warning questions for operations that are
4675 hard to recover from, e.g. rerunning the program while
4676 it is already running. Default is ON.
4678 editing on/off: Enables EMACS style command line editing
4679 of input. Previous lines can be recalled with
4680 control-P, the current line can be edited with control-B,
4681 you can search for commands with control-R, etc.
4684 history filename NAME: NAME is where the gdb command history
4685 will be stored. The default is .gdb_history,
4686 or the value of the environment variable
4689 history size N: The size, in commands, of the command history. The
4690 default is 256, or the value of the environment variable
4693 history save on/off: If this value is set to ON, the history file will
4694 be saved after exiting gdb. If set to OFF, the
4695 file will not be saved. The default is OFF.
4697 history expansion on/off: If this value is set to ON, then csh-like
4698 history expansion will be performed on
4699 command line input. The default is OFF.
4701 radix N: Sets the default radix for input and output. It can be set
4702 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4703 in the current radix, so "set radix 10" is always a no-op.
4705 height N: This integer value is the number of lines on a page. Default
4706 is 24, the current `stty rows'' setting, or the ``li#''
4707 setting from the termcap entry matching the environment
4710 width N: This integer value is the number of characters on a line.
4711 Default is 80, the current `stty cols'' setting, or the ``co#''
4712 setting from the termcap entry matching the environment
4715 Note: ``set screensize'' is obsolete. Use ``set height'' and
4716 ``set width'' instead.
4718 print address on/off: Print memory addresses in various command displays,
4719 such as stack traces and structure values. Gdb looks
4720 more ``symbolic'' if you turn this off; it looks more
4721 ``machine level'' with it on. Default is ON.
4723 print array on/off: Prettyprint arrays. New convenient format! Default
4726 print demangle on/off: Print C++ symbols in "source" form if on,
4729 print asm-demangle on/off: Same, for assembler level printouts
4732 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4735 * Support for Epoch Environment.
4737 The epoch environment is a version of Emacs v18 with windowing. One
4738 new command, ``inspect'', is identical to ``print'', except that if you
4739 are running in the epoch environment, the value is printed in its own
4743 * Support for Shared Libraries
4745 GDB can now debug programs and core files that use SunOS shared libraries.
4746 Symbols from a shared library cannot be referenced
4747 before the shared library has been linked with the program (this
4748 happens after you type ``run'' and before the function main() is entered).
4749 At any time after this linking (including when examining core files
4750 from dynamically linked programs), gdb reads the symbols from each
4751 shared library when you type the ``sharedlibrary'' command.
4752 It can be abbreviated ``share''.
4754 sharedlibrary REGEXP: Load shared object library symbols for files
4755 matching a unix regular expression. No argument
4756 indicates to load symbols for all shared libraries.
4758 info sharedlibrary: Status of loaded shared libraries.
4763 A watchpoint stops execution of a program whenever the value of an
4764 expression changes. Checking for this slows down execution
4765 tremendously whenever you are in the scope of the expression, but is
4766 quite useful for catching tough ``bit-spreader'' or pointer misuse
4767 problems. Some machines such as the 386 have hardware for doing this
4768 more quickly, and future versions of gdb will use this hardware.
4770 watch EXP: Set a watchpoint (breakpoint) for an expression.
4772 info watchpoints: Information about your watchpoints.
4774 delete N: Deletes watchpoint number N (same as breakpoints).
4775 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4776 enable N: Re-enables watchpoint number N (same as breakpoints).
4779 * C++ multiple inheritance
4781 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4784 * C++ exception handling
4786 Gdb now supports limited C++ exception handling. Besides the existing
4787 ability to breakpoint on an exception handler, gdb can breakpoint on
4788 the raising of an exception (before the stack is peeled back to the
4791 catch FOO: If there is a FOO exception handler in the dynamic scope,
4792 set a breakpoint to catch exceptions which may be raised there.
4793 Multiple exceptions (``catch foo bar baz'') may be caught.
4795 info catch: Lists all exceptions which may be caught in the
4796 current stack frame.
4799 * Minor command changes
4801 The command ``call func (arg, arg, ...)'' now acts like the print
4802 command, except it does not print or save a value if the function's result
4803 is void. This is similar to dbx usage.
4805 The ``up'' and ``down'' commands now always print the frame they end up
4806 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4807 frames without printing.
4809 * New directory command
4811 'dir' now adds directories to the FRONT of the source search path.
4812 The path starts off empty. Source files that contain debug information
4813 about the directory in which they were compiled can be found even
4814 with an empty path; Sun CC and GCC include this information. If GDB can't
4815 find your source file in the current directory, type "dir .".
4817 * Configuring GDB for compilation
4819 For normal use, type ``./configure host''. See README or gdb.texinfo
4822 GDB now handles cross debugging. If you are remotely debugging between
4823 two different machines, type ``./configure host -target=targ''.
4824 Host is the machine where GDB will run; targ is the machine
4825 where the program that you are debugging will run.