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 * GDBserver now supports stdio connections.
11 E.g. (gdb) target remote | ssh myhost gdbserver - hello
13 * The binary "gdbtui" can no longer be built or installed.
14 Use "gdb -tui" instead.
16 * GDB will now print "flag" enums specially. A flag enum is one where
17 all the enumerator values have no bits in common when pairwise
18 "and"ed. When printing a value whose type is a flag enum, GDB will
19 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
20 (gdb) print (enum E) 3
25 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
26 apply "flag enum"-style pretty-printing to any enum.
28 * The filename part of a linespec will now match trailing components
29 of a source file name. For example, "break gcc/expr.c:1000" will
30 now set a breakpoint in build/gcc/expr.c, but not
33 *** Changes in GDB 7.4
35 * GDB now handles ambiguous linespecs more consistently; the existing
36 FILE:LINE support has been expanded to other types of linespecs. A
37 breakpoint will now be set on all matching locations in all
38 inferiors, and locations will be added or removed according to
41 * GDB now allows you to skip uninteresting functions and files when
42 stepping with the "skip function" and "skip file" commands.
44 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
45 and "show remote hardware-watchpoint-length-limit". These allows to
46 set or show the maximum length limit (in bytes) of a remote
47 target hardware watchpoint.
49 This allows e.g. to use "unlimited" hardware watchpoints with the
50 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
51 watchpoints are slower than real hardware watchpoints but are
52 significantly faster than gdb software watchpoints.
56 ** The register_pretty_printer function in module gdb.printing now takes
57 an optional `replace' argument. If True, the new printer replaces any
60 ** The "maint set python print-stack on|off" command has been
61 deprecated and will be deleted in GDB 7.5.
62 A new command: "set python print-stack none|full|message" has
63 replaced it. Additionally, the default for "print-stack" is
64 now "message", which just prints the error message without
67 ** A prompt substitution hook (prompt_hook) is now available to the
70 ** A new Python module, gdb.prompt has been added to the GDB Python
71 modules library. This module provides functionality for
72 escape sequences in prompts (used by set/show
73 extended-prompt). These escape sequences are replaced by their
76 ** Python commands and convenience-functions located in
77 'data-directory'/python/gdb/command and
78 'data-directory'/python/gdb/function are now automatically loaded
81 ** Blocks now provide four new attributes. global_block and
82 static_block will return the global and static blocks
83 respectively. is_static and is_global are boolean attributes
84 that indicate if the block is one of those two types.
86 ** Symbols now provide the "type" attribute, the type of the symbol.
88 ** The "gdb.breakpoint" function has been deprecated in favor of
91 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
92 of a function. This class is based on the "finish" command
95 ** Type objects for struct and union types now allow access to
96 the fields using standard Python dictionary (mapping) methods.
97 For example, "some_type['myfield']" now works, as does
100 ** A new event "gdb.new_objfile" has been added, triggered by loading a
103 ** A new function, "deep_items" has been added to the gdb.types
104 module in the GDB Python modules library. This function returns
105 an iterator over the fields of a struct or union type. Unlike
106 the standard Python "iteritems" method, it will recursively traverse
107 any anonymous fields.
111 ** "*stopped" events can report several new "reason"s, such as
114 ** Breakpoint changes are now notified using new async records, like
115 "=breakpoint-modified".
117 ** New command -ada-task-info.
119 * libthread-db-search-path now supports two special values: $sdir and $pdir.
120 $sdir specifies the default system locations of shared libraries.
121 $pdir specifies the directory where the libpthread used by the application
124 GDB no longer looks in $sdir and $pdir after it has searched the directories
125 mentioned in libthread-db-search-path. If you want to search those
126 directories, they must be specified in libthread-db-search-path.
127 The default value of libthread-db-search-path on GNU/Linux and Solaris
128 systems is now "$sdir:$pdir".
130 $pdir is not supported by gdbserver, it is currently ignored.
131 $sdir is supported by gdbserver.
133 * New configure option --with-iconv-bin.
134 When using the internationalization support like the one in the GNU C
135 library, GDB will invoke the "iconv" program to get a list of supported
136 character sets. If this program lives in a non-standard location, one can
137 use this option to specify where to find it.
139 * When natively debugging programs on PowerPC BookE processors running
140 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
141 watchpoints, which specify a mask in addition to an address to watch.
142 The mask specifies that some bits of an address (the bits which are
143 reset in the mask) should be ignored when matching the address accessed
144 by the inferior against the watchpoint address. See the "PowerPC Embedded"
145 section in the user manual for more details.
147 * The new option --once causes GDBserver to stop listening for connections once
148 the first connection is made. The listening port used by GDBserver will
149 become available after that.
151 * New commands "info macros" and "alias" have been added.
153 * New function parameters suffix @entry specifies value of function parameter
154 at the time the function got called. Entry values are available only since
160 "!" is now an alias of the "shell" command.
161 Note that no space is needed between "!" and SHELL COMMAND.
165 watch EXPRESSION mask MASK_VALUE
166 The watch command now supports the mask argument which allows creation
167 of masked watchpoints, if the current architecture supports this feature.
169 info auto-load-scripts [REGEXP]
170 This command was formerly named "maintenance print section-scripts".
171 It is now generally useful and is no longer a maintenance-only command.
173 info macro [-all] [--] MACRO
174 The info macro command has new options `-all' and `--'. The first for
175 printing all definitions of a macro. The second for explicitly specifying
176 the end of arguments and the beginning of the macro name in case the macro
177 name starts with a hyphen.
179 collect[/s] EXPRESSIONS
180 The tracepoint collect command now takes an optional modifier "/s"
181 that directs it to dereference pointer-to-character types and
182 collect the bytes of memory up to a zero byte. The behavior is
183 similar to what you see when you use the regular print command on a
184 string. An optional integer following the "/s" sets a bound on the
185 number of bytes that will be collected.
188 The trace start command now interprets any supplied arguments as a
189 note to be recorded with the trace run, with an effect similar to
190 setting the variable trace-notes.
193 The trace stop command now interprets any arguments as a note to be
194 mentioned along with the tstatus report that the trace was stopped
195 with a command. The effect is similar to setting the variable
198 * Tracepoints can now be enabled and disabled at any time after a trace
199 experiment has been started using the standard "enable" and "disable"
200 commands. It is now possible to start a trace experiment with no enabled
201 tracepoints; GDB will display a warning, but will allow the experiment to
202 begin, assuming that tracepoints will be enabled as needed while the trace
205 * Fast tracepoints on 32-bit x86-architectures can now be placed at
206 locations with 4-byte instructions, when they were previously
207 limited to locations with instructions of 5 bytes or longer.
213 Set the GDB prompt, and allow escape sequences to be inserted to
214 display miscellaneous information (see 'help set extended-prompt'
215 for the list of sequences). This prompt (and any information
216 accessed through the escape sequences) is updated every time the
219 set print entry-values (both|compact|default|if-needed|no|only|preferred)
220 show print entry-values
221 Set printing of frame argument values at function entry. In some cases
222 GDB can determine the value of function argument which was passed by the
223 function caller, even if the value was modified inside the called function.
225 set debug entry-values
226 show debug entry-values
227 Control display of debugging info for determining frame argument values at
228 function entry and virtual tail call frames.
230 set basenames-may-differ
231 show basenames-may-differ
232 Set whether a source file may have multiple base names.
233 (A "base name" is the name of a file with the directory part removed.
234 Example: The base name of "/home/user/hello.c" is "hello.c".)
235 If set, GDB will canonicalize file names (e.g., expand symlinks)
236 before comparing them. Canonicalization is an expensive operation,
237 but it allows the same file be known by more than one base name.
238 If not set (the default), all source files are assumed to have just
239 one base name, and gdb will do file name comparisons more efficiently.
245 Set a user name and notes for the current and any future trace runs.
246 This is useful for long-running and/or disconnected traces, to
247 inform others (or yourself) as to who is running the trace, supply
248 contact information, or otherwise explain what is going on.
251 show trace-stop-notes
252 Set a note attached to the trace run, that is displayed when the
253 trace has been stopped by a tstop command. This is useful for
254 instance as an explanation, if you are stopping a trace run that was
255 started by someone else.
261 Dynamically enable a tracepoint in a started trace experiment.
265 Dynamically disable a tracepoint in a started trace experiment.
269 Set the user and notes of the trace run.
273 Query the current status of a tracepoint.
277 Query the minimum length of instruction at which a fast tracepoint may
280 * Dcache size (number of lines) and line-size are now runtime-configurable
281 via "set dcache line" and "set dcache line-size" commands.
285 Texas Instruments TMS320C6x tic6x-*-*
289 Renesas RL78 rl78-*-elf
291 *** Changes in GDB 7.3.1
293 * The build failure for NetBSD and OpenBSD targets have now been fixed.
295 *** Changes in GDB 7.3
297 * GDB has a new command: "thread find [REGEXP]".
298 It finds the thread id whose name, target id, or thread extra info
299 matches the given regular expression.
301 * The "catch syscall" command now works on mips*-linux* targets.
303 * The -data-disassemble MI command now supports modes 2 and 3 for
304 dumping the instruction opcodes.
306 * New command line options
308 -data-directory DIR Specify DIR as the "data-directory".
309 This is mostly for testing purposes.
311 * The "maint set python auto-load on|off" command has been renamed to
312 "set auto-load-scripts on|off".
314 * GDB has a new command: "set directories".
315 It is like the "dir" command except that it replaces the
316 source path list instead of augmenting it.
318 * GDB now understands thread names.
320 On GNU/Linux, "info threads" will display the thread name as set by
321 prctl or pthread_setname_np.
323 There is also a new command, "thread name", which can be used to
324 assign a name internally for GDB to display.
327 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
328 has been integrated into GDB.
332 ** The function gdb.Write now accepts an optional keyword 'stream'.
333 This keyword, when provided, will direct the output to either
334 stdout, stderr, or GDB's logging output.
336 ** Parameters can now be be sub-classed in Python, and in particular
337 you may implement the get_set_doc and get_show_doc functions.
338 This improves how Parameter set/show documentation is processed
339 and allows for more dynamic content.
341 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
342 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
343 have an is_valid method.
345 ** Breakpoints can now be sub-classed in Python, and in particular
346 you may implement a 'stop' function that is executed each time
347 the inferior reaches that breakpoint.
349 ** New function gdb.lookup_global_symbol looks up a global symbol.
351 ** GDB values in Python are now callable if the value represents a
352 function. For example, if 'some_value' represents a function that
353 takes two integer parameters and returns a value, you can call
354 that function like so:
356 result = some_value (10,20)
358 ** Module gdb.types has been added.
359 It contains a collection of utilities for working with gdb.Types objects:
360 get_basic_type, has_field, make_enum_dict.
362 ** Module gdb.printing has been added.
363 It contains utilities for writing and registering pretty-printers.
364 New classes: PrettyPrinter, SubPrettyPrinter,
365 RegexpCollectionPrettyPrinter.
366 New function: register_pretty_printer.
368 ** New commands "info pretty-printers", "enable pretty-printer" and
369 "disable pretty-printer" have been added.
371 ** gdb.parameter("directories") is now available.
373 ** New function gdb.newest_frame returns the newest frame in the
376 ** The gdb.InferiorThread class has a new "name" attribute. This
377 holds the thread's name.
379 ** Python Support for Inferior events.
380 Python scripts can add observers to be notified of events
381 occurring in the process being debugged.
382 The following events are currently supported:
383 - gdb.events.cont Continue event.
384 - gdb.events.exited Inferior exited event.
385 - gdb.events.stop Signal received, and Breakpoint hit events.
389 ** GDB now puts template parameters in scope when debugging in an
390 instantiation. For example, if you have:
392 template<int X> int func (void) { return X; }
394 then if you step into func<5>, "print X" will show "5". This
395 feature requires proper debuginfo support from the compiler; it
396 was added to GCC 4.5.
398 ** The motion commands "next", "finish", "until", and "advance" now
399 work better when exceptions are thrown. In particular, GDB will
400 no longer lose control of the inferior; instead, the GDB will
401 stop the inferior at the point at which the exception is caught.
402 This functionality requires a change in the exception handling
403 code that was introduced in GCC 4.5.
405 * GDB now follows GCC's rules on accessing volatile objects when
406 reading or writing target state during expression evaluation.
407 One notable difference to prior behavior is that "print x = 0"
408 no longer generates a read of x; the value of the assignment is
409 now always taken directly from the value being assigned.
411 * GDB now has some support for using labels in the program's source in
412 linespecs. For instance, you can use "advance label" to continue
413 execution to a label.
415 * GDB now has support for reading and writing a new .gdb_index
416 section. This section holds a fast index of DWARF debugging
417 information and can be used to greatly speed up GDB startup and
418 operation. See the documentation for `save gdb-index' for details.
420 * The "watch" command now accepts an optional "-location" argument.
421 When used, this causes GDB to watch the memory referred to by the
422 expression. Such a watchpoint is never deleted due to it going out
425 * GDB now supports thread debugging of core dumps on GNU/Linux.
427 GDB now activates thread debugging using the libthread_db library
428 when debugging GNU/Linux core dumps, similarly to when debugging
429 live processes. As a result, when debugging a core dump file, GDB
430 is now able to display pthread_t ids of threads. For example, "info
431 threads" shows the same output as when debugging the process when it
432 was live. In earlier releases, you'd see something like this:
435 * 1 LWP 6780 main () at main.c:10
437 While now you see this:
440 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
442 It is also now possible to inspect TLS variables when debugging core
445 When debugging a core dump generated on a machine other than the one
446 used to run GDB, you may need to point GDB at the correct
447 libthread_db library with the "set libthread-db-search-path"
448 command. See the user manual for more details on this command.
450 * When natively debugging programs on PowerPC BookE processors running
451 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
452 which stop execution of the inferior whenever it executes an instruction
453 at any address within the specified range. See the "PowerPC Embedded"
454 section in the user manual for more details.
456 * New features in the GDB remote stub, GDBserver
458 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
459 and i686 LynxOS (version 5.x).
461 ** GDBserver is now supported on Blackfin Linux.
463 * New native configurations
465 ia64 HP-UX ia64-*-hpux*
469 Analog Devices, Inc. Blackfin Processor bfin-*
471 * Ada task switching is now supported on sparc-elf targets when
472 debugging a program using the Ravenscar Profile. For more information,
473 see the "Tasking Support when using the Ravenscar Profile" section
474 in the GDB user manual.
476 * Guile support was removed.
478 * New features in the GNU simulator
480 ** The --map-info flag lists all known core mappings.
482 ** CFI flashes may be simulated via the "cfi" device.
484 *** Changes in GDB 7.2
486 * Shared library support for remote targets by default
488 When GDB is configured for a generic, non-OS specific target, like
489 for example, --target=arm-eabi or one of the many *-*-elf targets,
490 GDB now queries remote stubs for loaded shared libraries using the
491 `qXfer:libraries:read' packet. Previously, shared library support
492 was always disabled for such configurations.
496 ** Argument Dependent Lookup (ADL)
498 In C++ ADL lookup directs function search to the namespaces of its
499 arguments even if the namespace has not been imported.
509 Here the compiler will search for `foo' in the namespace of 'b'
510 and find A::foo. GDB now supports this. This construct is commonly
511 used in the Standard Template Library for operators.
513 ** Improved User Defined Operator Support
515 In addition to member operators, GDB now supports lookup of operators
516 defined in a namespace and imported with a `using' directive, operators
517 defined in the global scope, operators imported implicitly from an
518 anonymous namespace, and the ADL operators mentioned in the previous
520 GDB now also supports proper overload resolution for all the previously
521 mentioned flavors of operators.
523 ** static const class members
525 Printing of static const class members that are initialized in the
526 class definition has been fixed.
528 * Windows Thread Information Block access.
530 On Windows targets, GDB now supports displaying the Windows Thread
531 Information Block (TIB) structure. This structure is visible either
532 by using the new command `info w32 thread-information-block' or, by
533 dereferencing the new convenience variable named `$_tlb', a
534 thread-specific pointer to the TIB. This feature is also supported
535 when remote debugging using GDBserver.
539 Static tracepoints are calls in the user program into a tracing
540 library. One such library is a port of the LTTng kernel tracer to
541 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
542 When debugging with GDBserver, GDB now supports combining the GDB
543 tracepoint machinery with such libraries. For example: the user can
544 use GDB to probe a static tracepoint marker (a call from the user
545 program into the tracing library) with the new "strace" command (see
546 "New commands" below). This creates a "static tracepoint" in the
547 breakpoint list, that can be manipulated with the same feature set
548 as fast and regular tracepoints. E.g., collect registers, local and
549 global variables, collect trace state variables, and define
550 tracepoint conditions. In addition, the user can collect extra
551 static tracepoint marker specific data, by collecting the new
552 $_sdata internal variable. When analyzing the trace buffer, you can
553 inspect $_sdata like any other variable available to GDB. For more
554 information, see the "Tracepoints" chapter in GDB user manual. New
555 remote packets have been defined to support static tracepoints, see
556 the "New remote packets" section below.
558 * Better reconstruction of tracepoints after disconnected tracing
560 GDB will attempt to download the original source form of tracepoint
561 definitions when starting a trace run, and then will upload these
562 upon reconnection to the target, resulting in a more accurate
563 reconstruction of the tracepoints that are in use on the target.
567 You can now exercise direct control over the ways that GDB can
568 affect your program. For instance, you can disallow the setting of
569 breakpoints, so that the program can run continuously (assuming
570 non-stop mode). In addition, the "observer" variable is available
571 to switch all of the different controls; in observer mode, GDB
572 cannot affect the target's behavior at all, which is useful for
573 tasks like diagnosing live systems in the field.
575 * The new convenience variable $_thread holds the number of the
582 Return the address of the Windows Thread Information Block of a given thread.
586 In response to several of the tracepoint packets, the target may now
587 also respond with a number of intermediate `qRelocInsn' request
588 packets before the final result packet, to have GDB handle
589 relocating an instruction to execute at a different address. This
590 is particularly useful for stubs that support fast tracepoints. GDB
591 reports support for this feature in the qSupported packet.
595 List static tracepoint markers in the target program.
599 List static tracepoint markers at a given address in the target
602 qXfer:statictrace:read
604 Read the static trace data collected (by a `collect $_sdata'
605 tracepoint action). The remote stub reports support for this packet
606 to gdb's qSupported query.
610 Send the current settings of GDB's permission flags.
614 Send part of the source (textual) form of a tracepoint definition,
615 which includes location, conditional, and action list.
617 * The source command now accepts a -s option to force searching for the
618 script in the source search path even if the script name specifies
621 * New features in the GDB remote stub, GDBserver
623 - GDBserver now support tracepoints (including fast tracepoints, and
624 static tracepoints). The feature is currently supported by the
625 i386-linux and amd64-linux builds. See the "Tracepoints support
626 in gdbserver" section in the manual for more information.
628 GDBserver JIT compiles the tracepoint's conditional agent
629 expression bytecode into native code whenever possible for low
630 overhead dynamic tracepoints conditionals. For such tracepoints,
631 an expression that examines program state is evaluated when the
632 tracepoint is reached, in order to determine whether to capture
633 trace data. If the condition is simple and false, processing the
634 tracepoint finishes very quickly and no data is gathered.
636 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
637 for static tracepoints support.
639 - GDBserver now supports x86_64 Windows 64-bit debugging.
641 * GDB now sends xmlRegisters= in qSupported packet to indicate that
642 it understands register description.
644 * The --batch flag now disables pagination and queries.
646 * X86 general purpose registers
648 GDB now supports reading/writing byte, word and double-word x86
649 general purpose registers directly. This means you can use, say,
650 $ah or $ax to refer, respectively, to the byte register AH and
651 16-bit word register AX that are actually portions of the 32-bit
652 register EAX or 64-bit register RAX.
654 * The `commands' command now accepts a range of breakpoints to modify.
655 A plain `commands' following a command that creates multiple
656 breakpoints affects all the breakpoints set by that command. This
657 applies to breakpoints set by `rbreak', and also applies when a
658 single `break' command creates multiple breakpoints (e.g.,
659 breakpoints on overloaded c++ functions).
661 * The `rbreak' command now accepts a filename specification as part of
662 its argument, limiting the functions selected by the regex to those
663 in the specified file.
665 * Support for remote debugging Windows and SymbianOS shared libraries
666 from Unix hosts has been improved. Non Windows GDB builds now can
667 understand target reported file names that follow MS-DOS based file
668 system semantics, such as file names that include drive letters and
669 use the backslash character as directory separator. This makes it
670 possible to transparently use the "set sysroot" and "set
671 solib-search-path" on Unix hosts to point as host copies of the
672 target's shared libraries. See the new command "set
673 target-file-system-kind" described below, and the "Commands to
674 specify files" section in the user manual for more information.
678 eval template, expressions...
679 Convert the values of one or more expressions under the control
680 of the string template to a command line, and call it.
682 set target-file-system-kind unix|dos-based|auto
683 show target-file-system-kind
684 Set or show the assumed file system kind for target reported file
687 save breakpoints <filename>
688 Save all current breakpoint definitions to a file suitable for use
689 in a later debugging session. To read the saved breakpoint
690 definitions, use the `source' command.
692 `save tracepoints' is a new alias for `save-tracepoints'. The latter
695 info static-tracepoint-markers
696 Display information about static tracepoint markers in the target.
698 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
699 Define a static tracepoint by probing a marker at the given
700 function, line, address, or marker ID.
704 Enable and disable observer mode.
706 set may-write-registers on|off
707 set may-write-memory on|off
708 set may-insert-breakpoints on|off
709 set may-insert-tracepoints on|off
710 set may-insert-fast-tracepoints on|off
711 set may-interrupt on|off
712 Set individual permissions for GDB effects on the target. Note that
713 some of these settings can have undesirable or surprising
714 consequences, particularly when changed in the middle of a session.
715 For instance, disabling the writing of memory can prevent
716 breakpoints from being inserted, cause single-stepping to fail, or
717 even crash your program, if you disable after breakpoints have been
718 inserted. However, GDB should not crash.
720 set record memory-query on|off
721 show record memory-query
722 Control whether to stop the inferior if memory changes caused
723 by an instruction cannot be recorded.
728 The disassemble command now supports "start,+length" form of two arguments.
732 ** GDB now provides a new directory location, called the python directory,
733 where Python scripts written for GDB can be installed. The location
734 of that directory is <data-directory>/python, where <data-directory>
735 is the GDB data directory. For more details, see section `Scripting
736 GDB using Python' in the manual.
738 ** The GDB Python API now has access to breakpoints, symbols, symbol
739 tables, program spaces, inferiors, threads and frame's code blocks.
740 Additionally, GDB Parameters can now be created from the API, and
741 manipulated via set/show in the CLI.
743 ** New functions gdb.target_charset, gdb.target_wide_charset,
744 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
746 ** New exception gdb.GdbError.
748 ** Pretty-printers are now also looked up in the current program space.
750 ** Pretty-printers can now be individually enabled and disabled.
752 ** GDB now looks for names of Python scripts to auto-load in a
753 special section named `.debug_gdb_scripts', in addition to looking
754 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
756 * Tracepoint actions were unified with breakpoint commands. In particular,
757 there are no longer differences in "info break" output for breakpoints and
758 tracepoints and the "commands" command can be used for both tracepoints and
763 ARM Symbian arm*-*-symbianelf*
765 * D language support.
766 GDB now supports debugging programs written in the D programming
769 * GDB now supports the extended ptrace interface for PowerPC which is
770 available since Linux kernel version 2.6.34. This automatically enables
771 any hardware breakpoints and additional hardware watchpoints available in
772 the processor. The old ptrace interface exposes just one hardware
773 watchpoint and no hardware breakpoints.
775 * GDB is now able to use the Data Value Compare (DVC) register available on
776 embedded PowerPC processors to implement in hardware simple watchpoint
777 conditions of the form:
779 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
781 This works in native GDB running on Linux kernels with the extended ptrace
782 interface mentioned above.
784 *** Changes in GDB 7.1
790 GDB now supports importing of namespaces in C++. This enables the
791 user to inspect variables from imported namespaces. Support for
792 namepace aliasing has also been added. So, if a namespace is
793 aliased in the current scope (e.g. namepace C=A; ) the user can
794 print variables using the alias (e.g. (gdb) print C::x).
798 All known bugs relating to the printing of virtual base class were
799 fixed. It is now possible to call overloaded static methods using a
804 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
805 and reinterpret_cast<> are now handled by the C++ expression parser.
809 Xilinx MicroBlaze microblaze-*-*
814 Xilinx MicroBlaze microblaze
817 * Multi-program debugging.
819 GDB now has support for multi-program (a.k.a. multi-executable or
820 multi-exec) debugging. This allows for debugging multiple inferiors
821 simultaneously each running a different program under the same GDB
822 session. See "Debugging Multiple Inferiors and Programs" in the
823 manual for more information. This implied some user visible changes
824 in the multi-inferior support. For example, "info inferiors" now
825 lists inferiors that are not running yet or that have exited
826 already. See also "New commands" and "New options" below.
828 * New tracing features
830 GDB's tracepoint facility now includes several new features:
832 ** Trace state variables
834 GDB tracepoints now include support for trace state variables, which
835 are variables managed by the target agent during a tracing
836 experiment. They are useful for tracepoints that trigger each
837 other, so for instance one tracepoint can count hits in a variable,
838 and then a second tracepoint has a condition that is true when the
839 count reaches a particular value. Trace state variables share the
840 $-syntax of GDB convenience variables, and can appear in both
841 tracepoint actions and condition expressions. Use the "tvariable"
842 command to create, and "info tvariables" to view; see "Trace State
843 Variables" in the manual for more detail.
847 GDB now includes an option for defining fast tracepoints, which
848 targets may implement more efficiently, such as by installing a jump
849 into the target agent rather than a trap instruction. The resulting
850 speedup can be by two orders of magnitude or more, although the
851 tradeoff is that some program locations on some target architectures
852 might not allow fast tracepoint installation, for instance if the
853 instruction to be replaced is shorter than the jump. To request a
854 fast tracepoint, use the "ftrace" command, with syntax identical to
855 the regular trace command.
857 ** Disconnected tracing
859 It is now possible to detach GDB from the target while it is running
860 a trace experiment, then reconnect later to see how the experiment
861 is going. In addition, a new variable disconnected-tracing lets you
862 tell the target agent whether to continue running a trace if the
863 connection is lost unexpectedly.
867 GDB now has the ability to save the trace buffer into a file, and
868 then use that file as a target, similarly to you can do with
869 corefiles. You can select trace frames, print data that was
870 collected in them, and use tstatus to display the state of the
871 tracing run at the moment that it was saved. To create a trace
872 file, use "tsave <filename>", and to use it, do "target tfile
875 ** Circular trace buffer
877 You can ask the target agent to handle the trace buffer as a
878 circular buffer, discarding the oldest trace frames to make room for
879 newer ones, by setting circular-trace-buffer to on. This feature may
880 not be available for all target agents.
885 The disassemble command, when invoked with two arguments, now requires
886 the arguments to be comma-separated.
889 The info variables command now displays variable definitions. Files
890 which only declare a variable are not shown.
893 The source command is now capable of sourcing Python scripts.
894 This feature is dependent on the debugger being build with Python
897 Related to this enhancement is also the introduction of a new command
898 "set script-extension" (see below).
900 * New commands (for set/show, see "New options" below)
902 record save [<FILENAME>]
903 Save a file (in core file format) containing the process record
904 execution log for replay debugging at a later time.
906 record restore <FILENAME>
907 Restore the process record execution log that was saved at an
908 earlier time, for replay debugging.
910 add-inferior [-copies <N>] [-exec <FILENAME>]
913 clone-inferior [-copies <N>] [ID]
914 Make a new inferior ready to execute the same program another
920 maint info program-spaces
921 List the program spaces loaded into GDB.
923 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
924 show remote interrupt-sequence
925 Allow the user to select one of ^C, a BREAK signal or BREAK-g
926 as the sequence to the remote target in order to interrupt the execution.
927 Ctrl-C is a default. Some system prefers BREAK which is high level of
928 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
929 Magic SysRq g. It is BREAK signal and character 'g'.
931 set remote interrupt-on-connect [on | off]
932 show remote interrupt-on-connect
933 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
934 remote target when gdb connects to it. This is needed when you debug
937 set remotebreak [on | off]
939 Deprecated. Use "set/show remote interrupt-sequence" instead.
941 tvariable $NAME [ = EXP ]
942 Create or modify a trace state variable.
945 List trace state variables and their values.
947 delete tvariable $NAME ...
948 Delete one or more trace state variables.
951 Evaluate the given expressions without collecting anything into the
952 trace buffer. (Valid in tracepoint actions only.)
954 ftrace FN / FILE:LINE / *ADDR
955 Define a fast tracepoint at the given function, line, or address.
957 * New expression syntax
959 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
960 GDB now parses 0b101010 identically with 42.
964 set follow-exec-mode new|same
965 show follow-exec-mode
966 Control whether GDB reuses the same inferior across an exec call or
967 creates a new one. This is useful to be able to restart the old
968 executable after the inferior having done an exec call.
970 set default-collect EXPR, ...
972 Define a list of expressions to be collected at each tracepoint.
973 This is a useful way to ensure essential items are not overlooked,
974 such as registers or a critical global variable.
976 set disconnected-tracing
977 show disconnected-tracing
978 If set to 1, the target is instructed to continue tracing if it
979 loses its connection to GDB. If 0, the target is to stop tracing
982 set circular-trace-buffer
983 show circular-trace-buffer
984 If set to on, the target is instructed to use a circular trace buffer
985 and discard the oldest trace frames instead of stopping the trace due
986 to a full trace buffer. If set to off, the trace stops when the buffer
987 fills up. Some targets may not support this.
989 set script-extension off|soft|strict
990 show script-extension
991 If set to "off", the debugger does not perform any script language
992 recognition, and all sourced files are assumed to be GDB scripts.
993 If set to "soft" (the default), files are sourced according to
994 filename extension, falling back to GDB scripts if the first
996 If set to "strict", files are sourced according to filename extension.
998 set ada trust-PAD-over-XVS on|off
999 show ada trust-PAD-over-XVS
1000 If off, activate a workaround against a bug in the debugging information
1001 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1002 the GCC sources for more information about the GNAT encoding and
1003 PAD types in particular). It is always safe to set this option to
1004 off, but this introduces a slight performance penalty. The default
1007 * Python API Improvements
1009 ** GDB provides the new class gdb.LazyString. This is useful in
1010 some pretty-printing cases. The new method gdb.Value.lazy_string
1011 provides a simple way to create objects of this type.
1013 ** The fields returned by gdb.Type.fields now have an
1014 `is_base_class' attribute.
1016 ** The new method gdb.Type.range returns the range of an array type.
1018 ** The new method gdb.parse_and_eval can be used to parse and
1019 evaluate an expression.
1021 * New remote packets
1024 Define a trace state variable.
1027 Get the current value of a trace state variable.
1030 Set desired tracing behavior upon disconnection.
1033 Set the trace buffer to be linear or circular.
1036 Get data about the tracepoints currently in use.
1040 Process record now works correctly with hardware watchpoints.
1042 Multiple bug fixes have been made to the mips-irix port, making it
1043 much more reliable. In particular:
1044 - Debugging threaded applications is now possible again. Previously,
1045 GDB would hang while starting the program, or while waiting for
1046 the program to stop at a breakpoint.
1047 - Attaching to a running process no longer hangs.
1048 - An error occurring while loading a core file has been fixed.
1049 - Changing the value of the PC register now works again. This fixes
1050 problems observed when using the "jump" command, or when calling
1051 a function from GDB, or even when assigning a new value to $pc.
1052 - With the "finish" and "return" commands, the return value for functions
1053 returning a small array is now correctly printed.
1054 - It is now possible to break on shared library code which gets executed
1055 during a shared library init phase (code executed while executing
1056 their .init section). Previously, the breakpoint would have no effect.
1057 - GDB is now able to backtrace through the signal handler for
1058 non-threaded programs.
1060 PIE (Position Independent Executable) programs debugging is now supported.
1061 This includes debugging execution of PIC (Position Independent Code) shared
1062 libraries although for that, it should be possible to run such libraries as an
1065 *** Changes in GDB 7.0
1067 * GDB now has an interface for JIT compilation. Applications that
1068 dynamically generate code can create symbol files in memory and register
1069 them with GDB. For users, the feature should work transparently, and
1070 for JIT developers, the interface is documented in the GDB manual in the
1071 "JIT Compilation Interface" chapter.
1073 * Tracepoints may now be conditional. The syntax is as for
1074 breakpoints; either an "if" clause appended to the "trace" command,
1075 or the "condition" command is available. GDB sends the condition to
1076 the target for evaluation using the same bytecode format as is used
1077 for tracepoint actions.
1079 * The disassemble command now supports: an optional /r modifier, print the
1080 raw instructions in hex as well as in symbolic form, and an optional /m
1081 modifier to print mixed source+assembly.
1083 * Process record and replay
1085 In a architecture environment that supports ``process record and
1086 replay'', ``process record and replay'' target can record a log of
1087 the process execution, and replay it with both forward and reverse
1090 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1091 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1092 set execution-direction {forward|reverse}, for targets that support
1095 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1096 feature is available with a native GDB running on kernel version
1099 * GDB now has support for multi-byte and wide character sets on the
1100 target. Strings whose character type is wchar_t, char16_t, or
1101 char32_t are now correctly printed. GDB supports wide- and unicode-
1102 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1103 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1104 `printf'. This feature requires iconv to work properly; if your
1105 system does not have a working iconv, GDB can use GNU libiconv. See
1106 the installation instructions for more information.
1108 * GDB now supports automatic retrieval of shared library files from
1109 remote targets. To use this feature, specify a system root that begins
1110 with the `remote:' prefix, either via the `set sysroot' command or via
1111 the `--with-sysroot' configure-time option.
1113 * "info sharedlibrary" now takes an optional regex of libraries to show,
1114 and it now reports if a shared library has no debugging information.
1116 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1117 now complete on file names.
1119 * When completing in expressions, gdb will attempt to limit
1120 completions to allowable structure or union fields, where appropriate.
1121 For instance, consider:
1123 # struct example { int f1; double f2; };
1124 # struct example variable;
1127 If the user types TAB at the end of this command line, the available
1128 completions will be "f1" and "f2".
1130 * Inlined functions are now supported. They show up in backtraces, and
1131 the "step", "next", and "finish" commands handle them automatically.
1133 * GDB now supports the token-splicing (##) and stringification (#)
1134 operators when expanding macros. It also supports variable-arity
1137 * GDB now supports inspecting extra signal information, exported by
1138 the new $_siginfo convenience variable. The feature is currently
1139 implemented on linux ARM, i386 and amd64.
1141 * GDB can now display the VFP floating point registers and NEON vector
1142 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1143 can provide these registers (requires Linux 2.6.30 or later). Remote
1144 and simulator targets may also provide them.
1146 * New remote packets
1149 Search memory for a sequence of bytes.
1152 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1153 operation over reliable transport links. Use of this packet is
1154 controlled by the `set remote noack-packet' command.
1157 Kill the process with the specified process ID. Use this in preference
1158 to `k' when multiprocess protocol extensions are supported.
1161 Obtains additional operating system information
1165 Read or write additional signal information.
1167 * Removed remote protocol undocumented extension
1169 An undocumented extension to the remote protocol's `S' stop reply
1170 packet that permited the stub to pass a process id was removed.
1171 Remote servers should use the `T' stop reply packet instead.
1173 * GDB now supports multiple function calling conventions according to the
1174 DWARF-2 DW_AT_calling_convention function attribute.
1176 * The SH target utilizes the aforementioned change to distinguish between gcc
1177 and Renesas calling convention. It also adds the new CLI commands
1178 `set/show sh calling-convention'.
1180 * GDB can now read compressed debug sections, as produced by GNU gold
1181 with the --compress-debug-sections=zlib flag.
1183 * 64-bit core files are now supported on AIX.
1185 * Thread switching is now supported on Tru64.
1187 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1188 which will be allocated using malloc later in program execution.
1190 * The qXfer:libraries:read remote procotol packet now allows passing a
1191 list of section offsets.
1193 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1194 conditions handling signals delivered during attach or thread creation
1195 have also been fixed.
1197 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1198 From the user's standpoint, all unqualified instances of True and False
1199 are treated as the standard definitions, regardless of context.
1201 * GDB now parses C++ symbol and type names more flexibly. For
1204 template<typename T> class C { };
1207 GDB will now correctly handle all of:
1209 ptype C<char const *>
1210 ptype C<char const*>
1211 ptype C<const char *>
1212 ptype C<const char*>
1214 * New features in the GDB remote stub, gdbserver
1216 - The "--wrapper" command-line argument tells gdbserver to use a
1217 wrapper program to launch programs for debugging.
1219 - On PowerPC and S/390 targets, it is now possible to use a single
1220 gdbserver executable to debug both 32-bit and 64-bit programs.
1221 (This requires gdbserver itself to be built as a 64-bit executable.)
1223 - gdbserver uses the new noack protocol mode for TCP connections to
1224 reduce communications latency, if also supported and enabled in GDB.
1226 - Support for the sparc64-linux-gnu target is now included in
1229 - The amd64-linux build of gdbserver now supports debugging both
1230 32-bit and 64-bit programs.
1232 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1233 now support hardware watchpoints, and will use them automatically
1238 GDB now has support for scripting using Python. Whether this is
1239 available is determined at configure time.
1241 New GDB commands can now be written in Python.
1243 * Ada tasking support
1245 Ada tasks can now be inspected in GDB. The following commands have
1249 Print the list of Ada tasks.
1251 Print detailed information about task number N.
1253 Print the task number of the current task.
1255 Switch the context of debugging to task number N.
1257 * Support for user-defined prefixed commands. The "define" command can
1258 add new commands to existing prefixes, e.g. "target".
1260 * Multi-inferior, multi-process debugging.
1262 GDB now has generalized support for multi-inferior debugging. See
1263 "Debugging Multiple Inferiors" in the manual for more information.
1264 Although availability still depends on target support, the command
1265 set is more uniform now. The GNU/Linux specific multi-forks support
1266 has been migrated to this new framework. This implied some user
1267 visible changes; see "New commands" and also "Removed commands"
1270 * Target descriptions can now describe the target OS ABI. See the
1271 "Target Description Format" section in the user manual for more
1274 * Target descriptions can now describe "compatible" architectures
1275 to indicate that the target can execute applications for a different
1276 architecture in addition to those for the main target architecture.
1277 See the "Target Description Format" section in the user manual for
1280 * Multi-architecture debugging.
1282 GDB now includes general supports for debugging applications on
1283 hybrid systems that use more than one single processor architecture
1284 at the same time. Each such hybrid architecture still requires
1285 specific support to be added. The only hybrid architecture supported
1286 in this version of GDB is the Cell Broadband Engine.
1288 * GDB now supports integrated debugging of Cell/B.E. applications that
1289 use both the PPU and SPU architectures. To enable support for hybrid
1290 Cell/B.E. debugging, you need to configure GDB to support both the
1291 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1292 --enable-targets configure option.
1294 * Non-stop mode debugging.
1296 For some targets, GDB now supports an optional mode of operation in
1297 which you can examine stopped threads while other threads continue
1298 to execute freely. This is referred to as non-stop mode, with the
1299 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1300 section in the user manual for more information.
1302 To be able to support remote non-stop debugging, a remote stub needs
1303 to implement the non-stop mode remote protocol extensions, as
1304 described in the "Remote Non-Stop" section of the user manual. The
1305 GDB remote stub, gdbserver, has been adjusted to support these
1306 extensions on linux targets.
1308 * New commands (for set/show, see "New options" below)
1310 catch syscall [NAME(S) | NUMBER(S)]
1311 Catch system calls. Arguments, which should be names of system
1312 calls or their numbers, mean catch only those syscalls. Without
1313 arguments, every syscall will be caught. When the inferior issues
1314 any of the specified syscalls, GDB will stop and announce the system
1315 call, both when it is called and when its call returns. This
1316 feature is currently available with a native GDB running on the
1317 Linux Kernel, under the following architectures: x86, x86_64,
1318 PowerPC and PowerPC64.
1320 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1322 Search memory for a sequence of bytes.
1324 maint set python print-stack
1325 maint show python print-stack
1326 Show a stack trace when an error is encountered in a Python script.
1329 Invoke CODE by passing it to the Python interpreter.
1334 These allow macros to be defined, undefined, and listed
1338 Show operating system information about processes.
1341 List the inferiors currently under GDB's control.
1344 Switch focus to inferior number NUM.
1347 Detach from inferior number NUM.
1350 Kill inferior number NUM.
1354 set spu stop-on-load
1355 show spu stop-on-load
1356 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1358 set spu auto-flush-cache
1359 show spu auto-flush-cache
1360 Control whether to automatically flush the software-managed cache
1361 during Cell/B.E. debugging.
1363 set sh calling-convention
1364 show sh calling-convention
1365 Control the calling convention used when calling SH target functions.
1368 show debug timestamp
1369 Control display of timestamps with GDB debugging output.
1371 set disassemble-next-line
1372 show disassemble-next-line
1373 Control display of disassembled source lines or instructions when
1376 set remote noack-packet
1377 show remote noack-packet
1378 Set/show the use of remote protocol QStartNoAckMode packet. See above
1379 under "New remote packets."
1381 set remote query-attached-packet
1382 show remote query-attached-packet
1383 Control use of remote protocol `qAttached' (query-attached) packet.
1385 set remote read-siginfo-object
1386 show remote read-siginfo-object
1387 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1390 set remote write-siginfo-object
1391 show remote write-siginfo-object
1392 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1395 set remote reverse-continue
1396 show remote reverse-continue
1397 Control use of remote protocol 'bc' (reverse-continue) packet.
1399 set remote reverse-step
1400 show remote reverse-step
1401 Control use of remote protocol 'bs' (reverse-step) packet.
1403 set displaced-stepping
1404 show displaced-stepping
1405 Control displaced stepping mode. Displaced stepping is a way to
1406 single-step over breakpoints without removing them from the debuggee.
1407 Also known as "out-of-line single-stepping".
1410 show debug displaced
1411 Control display of debugging info for displaced stepping.
1413 maint set internal-error
1414 maint show internal-error
1415 Control what GDB does when an internal error is detected.
1417 maint set internal-warning
1418 maint show internal-warning
1419 Control what GDB does when an internal warning is detected.
1424 Use a wrapper program to launch programs for debugging.
1426 set multiple-symbols (all|ask|cancel)
1427 show multiple-symbols
1428 The value of this variable can be changed to adjust the debugger behavior
1429 when an expression or a breakpoint location contains an ambiguous symbol
1430 name (an overloaded function name, for instance).
1432 set breakpoint always-inserted
1433 show breakpoint always-inserted
1434 Keep breakpoints always inserted in the target, as opposed to inserting
1435 them when resuming the target, and removing them when the target stops.
1436 This option can improve debugger performance on slow remote targets.
1438 set arm fallback-mode (arm|thumb|auto)
1439 show arm fallback-mode
1440 set arm force-mode (arm|thumb|auto)
1442 These commands control how ARM GDB determines whether instructions
1443 are ARM or Thumb. The default for both settings is auto, which uses
1444 the current CPSR value for instructions without symbols; previous
1445 versions of GDB behaved as if "set arm fallback-mode arm".
1447 set disable-randomization
1448 show disable-randomization
1449 Standalone programs run with the virtual address space randomization enabled
1450 by default on some platforms. This option keeps the addresses stable across
1451 multiple debugging sessions.
1455 Control whether other threads are stopped or not when some thread hits
1460 Requests that asynchronous execution is enabled in the target, if available.
1461 In this case, it's possible to resume target in the background, and interact
1462 with GDB while the target is running. "show target-async" displays the
1463 current state of asynchronous execution of the target.
1465 set target-wide-charset
1466 show target-wide-charset
1467 The target-wide-charset is the name of the character set that GDB
1468 uses when printing characters whose type is wchar_t.
1470 set tcp auto-retry (on|off)
1472 set tcp connect-timeout
1473 show tcp connect-timeout
1474 These commands allow GDB to retry failed TCP connections to a remote stub
1475 with a specified timeout period; this is useful if the stub is launched
1476 in parallel with GDB but may not be ready to accept connections immediately.
1478 set libthread-db-search-path
1479 show libthread-db-search-path
1480 Control list of directories which GDB will search for appropriate
1483 set schedule-multiple (on|off)
1484 show schedule-multiple
1485 Allow GDB to resume all threads of all processes or only threads of
1486 the current process.
1490 Use more aggressive caching for accesses to the stack. This improves
1491 performance of remote debugging (particularly backtraces) without
1492 affecting correctness.
1494 set interactive-mode (on|off|auto)
1495 show interactive-mode
1496 Control whether GDB runs in interactive mode (on) or not (off).
1497 When in interactive mode, GDB waits for the user to answer all
1498 queries. Otherwise, GDB does not wait and assumes the default
1499 answer. When set to auto (the default), GDB determines which
1500 mode to use based on the stdin settings.
1505 For program forks, this is replaced by the new more generic `info
1506 inferiors' command. To list checkpoints, you can still use the
1507 `info checkpoints' command, which was an alias for the `info forks'
1511 Replaced by the new `inferior' command. To switch between
1512 checkpoints, you can still use the `restart' command, which was an
1513 alias for the `fork' command.
1516 This is removed, since some targets don't have a notion of
1517 processes. To switch between processes, you can still use the
1518 `inferior' command using GDB's own inferior number.
1521 For program forks, this is replaced by the new more generic `kill
1522 inferior' command. To delete a checkpoint, you can still use the
1523 `delete checkpoint' command, which was an alias for the `delete
1527 For program forks, this is replaced by the new more generic `detach
1528 inferior' command. To detach a checkpoint, you can still use the
1529 `detach checkpoint' command, which was an alias for the `detach
1532 * New native configurations
1534 x86/x86_64 Darwin i[34567]86-*-darwin*
1536 x86_64 MinGW x86_64-*-mingw*
1540 Lattice Mico32 lm32-*
1541 x86 DICOS i[34567]86-*-dicos*
1542 x86_64 DICOS x86_64-*-dicos*
1545 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1546 (mingw32ce) debugging.
1552 These commands were actually not implemented on any target.
1554 *** Changes in GDB 6.8
1556 * New native configurations
1558 NetBSD/hppa hppa*-*netbsd*
1559 Xtensa GNU/Linux xtensa*-*-linux*
1563 NetBSD/hppa hppa*-*-netbsd*
1564 Xtensa GNU/Lunux xtensa*-*-linux*
1566 * Change in command line behavior -- corefiles vs. process ids.
1568 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1569 attaching to process NUMBER fails, GDB no longer attempts to open a
1570 core file named NUMBER. Attaching to a program using the -c option
1571 is no longer supported. Instead, use the '-p' or '--pid' options.
1573 * GDB can now be built as a native debugger for debugging Windows x86
1574 (mingw32) Portable Executable (PE) programs.
1576 * Pending breakpoints no longer change their number when their address
1579 * GDB now supports breakpoints with multiple locations,
1580 including breakpoints on C++ constructors, inside C++ templates,
1581 and in inlined functions.
1583 * GDB's ability to debug optimized code has been improved. GDB more
1584 accurately identifies function bodies and lexical blocks that occupy
1585 more than one contiguous range of addresses.
1587 * Target descriptions can now describe registers for PowerPC.
1589 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1590 registers on PowerPC targets.
1592 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1593 targets even when the libthread_db library is not available.
1595 * The GDB remote stub, gdbserver, now supports the new file transfer
1596 commands (remote put, remote get, and remote delete).
1598 * The GDB remote stub, gdbserver, now supports run and attach in
1599 extended-remote mode.
1601 * hppa*64*-*-hpux11* target broken
1602 The debugger is unable to start a program and fails with the following
1603 error: "Error trying to get information about dynamic linker".
1604 The gdb-6.7 release is also affected.
1606 * GDB now supports the --enable-targets= configure option to allow
1607 building a single GDB executable that supports multiple remote
1608 target architectures.
1610 * GDB now supports debugging C and C++ programs which use the
1611 Decimal Floating Point extension. In addition, the PowerPC target
1612 now has a set of pseudo-registers to inspect decimal float values
1613 stored in two consecutive float registers.
1615 * The -break-insert MI command can optionally create pending
1618 * Improved support for debugging Ada
1619 Many improvements to the Ada language support have been made. These
1621 - Better support for Ada2005 interface types
1622 - Improved handling of arrays and slices in general
1623 - Better support for Taft-amendment types
1624 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1626 - Improved command completion in Ada
1629 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1634 set print frame-arguments (all|scalars|none)
1635 show print frame-arguments
1636 The value of this variable can be changed to control which argument
1637 values should be printed by the debugger when displaying a frame.
1642 Transfer files to and from a remote target, and delete remote files.
1649 Transfer files to and from a remote target, and delete remote files.
1651 * New remote packets
1658 Open, close, read, write, and delete files on the remote system.
1661 Attach to an existing process on the remote system, in extended-remote
1665 Run a new process on the remote system, in extended-remote mode.
1667 *** Changes in GDB 6.7
1669 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1670 bfd, libiberty and opcodes, as revealed by static analysis donated by
1671 Coverity, Inc. (http://scan.coverity.com).
1673 * When looking up multiply-defined global symbols, GDB will now prefer the
1674 symbol definition in the current shared library if it was built using the
1675 -Bsymbolic linker option.
1677 * When the Text User Interface (TUI) is not configured, GDB will now
1678 recognize the -tui command-line option and print a message that the TUI
1681 * The GDB remote stub, gdbserver, now has lower overhead for high
1682 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1684 * GDB for MIPS targets now autodetects whether a remote target provides
1685 32-bit or 64-bit register values.
1687 * Support for C++ member pointers has been improved.
1689 * GDB now understands XML target descriptions, which specify the
1690 target's overall architecture. GDB can read a description from
1691 a local file or over the remote serial protocol.
1693 * Vectors of single-byte data use a new integer type which is not
1694 automatically displayed as character or string data.
1696 * The /s format now works with the print command. It displays
1697 arrays of single-byte integers and pointers to single-byte integers
1700 * Target descriptions can now describe target-specific registers,
1701 for architectures which have implemented the support (currently
1702 only ARM, M68K, and MIPS).
1704 * GDB and the GDB remote stub, gdbserver, now support the XScale
1707 * The GDB remote stub, gdbserver, has been updated to support
1708 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1709 has been rewritten to use the standard GDB remote protocol.
1711 * GDB can now step into C++ functions which are called through thunks.
1713 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1715 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1716 layout. It also supports a TextSeg= and DataSeg= response when only
1717 segment base addresses (rather than offsets) are available.
1719 * The /i format now outputs any trailing branch delay slot instructions
1720 immediately following the last instruction within the count specified.
1722 * The GDB remote protocol "T" stop reply packet now supports a
1723 "library" response. Combined with the new "qXfer:libraries:read"
1724 packet, this response allows GDB to debug shared libraries on targets
1725 where the operating system manages the list of loaded libraries (e.g.
1726 Windows and SymbianOS).
1728 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1729 (DLLs) on Windows and Windows CE targets.
1731 * GDB now supports a faster verification that a .debug file matches its binary
1732 according to its build-id signature, if the signature is present.
1738 Enable or disable hardware flow control (RTS/CTS) on the serial port
1739 when debugging using remote targets.
1741 set mem inaccessible-by-default
1742 show mem inaccessible-by-default
1743 If the target supplies a memory map, for instance via the remote
1744 protocol's "qXfer:memory-map:read" packet, setting this variable
1745 prevents GDB from accessing memory outside the memory map. This
1746 is useful for targets with memory mapped registers or which react
1747 badly to accesses of unmapped address space.
1749 set breakpoint auto-hw
1750 show breakpoint auto-hw
1751 If the target supplies a memory map, for instance via the remote
1752 protocol's "qXfer:memory-map:read" packet, setting this variable
1753 lets GDB use hardware breakpoints automatically for memory regions
1754 where it can not use software breakpoints. This covers both the
1755 "break" command and internal breakpoints used for other commands
1756 including "next" and "finish".
1759 catch exception unhandled
1760 Stop the program execution when Ada exceptions are raised.
1763 Stop the program execution when an Ada assertion failed.
1767 Set an alternate system root for target files. This is a more
1768 general version of "set solib-absolute-prefix", which is now
1769 an alias to "set sysroot".
1772 Provide extended SPU facility status information. This set of
1773 commands is available only when debugging the Cell/B.E. SPU
1776 * New native configurations
1778 OpenBSD/sh sh*-*openbsd*
1781 unset tdesc filename
1783 Use the specified local file as an XML target description, and do
1784 not query the target for its built-in description.
1788 OpenBSD/sh sh*-*-openbsd*
1789 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1790 Toshiba Media Processor mep-elf
1792 * New remote packets
1795 Ignore the specified signals; pass them directly to the debugged program
1796 without stopping other threads or reporting them to GDB.
1798 qXfer:features:read:
1799 Read an XML target description from the target, which describes its
1804 Read or write contents of an spufs file on the target system. These
1805 packets are available only on the Cell/B.E. SPU architecture.
1807 qXfer:libraries:read:
1808 Report the loaded shared libraries. Combined with new "T" packet
1809 response, this packet allows GDB to debug shared libraries on
1810 targets where the operating system manages the list of loaded
1811 libraries (e.g. Windows and SymbianOS).
1815 Support for these obsolete configurations has been removed.
1823 i[34567]86-*-lynxos*
1824 i[34567]86-*-netware*
1825 i[34567]86-*-sco3.2v5*
1826 i[34567]86-*-sco3.2v4*
1828 i[34567]86-*-sysv4.2*
1831 i[34567]86-*-unixware2*
1832 i[34567]86-*-unixware*
1841 * Other removed features
1848 Various m68k-only ROM monitors.
1855 Various Renesas ROM monitors and debugging interfaces for SH and
1860 Support for a Macraigor serial interface to on-chip debugging.
1861 GDB does not directly support the newer parallel or USB
1866 A debug information format. The predecessor to DWARF 2 and
1867 DWARF 3, which are still supported.
1869 Support for the HP aCC compiler on HP-UX/PA-RISC
1871 SOM-encapsulated symbolic debugging information, automatic
1872 invocation of pxdb, and the aCC custom C++ ABI. This does not
1873 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1874 with aCC can still be debugged on an assembly level.
1876 MIPS ".pdr" sections
1878 A MIPS-specific format used to describe stack frame layout
1879 in debugging information.
1883 GDB could work with an older version of Guile to debug
1884 the interpreter and Scheme programs running in it.
1886 set mips stack-arg-size
1887 set mips saved-gpreg-size
1889 Use "set mips abi" to control parameter passing for MIPS.
1891 *** Changes in GDB 6.6
1896 Cell Broadband Engine SPU spu-elf
1898 * GDB can now be configured as a cross-debugger targeting native Windows
1899 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1900 running on a Windows system over TCP/IP to debug Windows programs.
1902 * The GDB remote stub, gdbserver, has been updated to support Windows and
1903 Cygwin debugging. Both single-threaded and multi-threaded programs are
1906 * The "set trust-readonly-sections" command works again. This command was
1907 broken in GDB 6.3, 6.4, and 6.5.
1909 * The "load" command now supports writing to flash memory, if the remote
1910 stub provides the required support.
1912 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1913 longer requires symbolic debug information (e.g. DWARF-2).
1918 unset substitute-path
1919 show substitute-path
1920 Manage a list of substitution rules that GDB uses to rewrite the name
1921 of the directories where the sources are located. This can be useful
1922 for instance when the sources were moved to a different location
1923 between compilation and debugging.
1927 Print each CLI command as it is executed. Each command is prefixed with
1928 a number of `+' symbols representing the nesting depth.
1929 The source command now has a `-v' option to enable the same feature.
1933 The ARM Demon monitor support (RDP protocol, "target rdp").
1935 Kernel Object Display, an embedded debugging feature which only worked with
1936 an obsolete version of Cisco IOS.
1938 The 'set download-write-size' and 'show download-write-size' commands.
1940 * New remote packets
1943 Tell a stub about GDB client features, and request remote target features.
1944 The first feature implemented is PacketSize, which allows the target to
1945 specify the size of packets it can handle - to minimize the number of
1946 packets required and improve performance when connected to a remote
1950 Fetch an OS auxilliary vector from the remote stub. This packet is a
1951 more efficient replacement for qPart:auxv:read.
1953 qXfer:memory-map:read:
1954 Fetch a memory map from the remote stub, including information about
1955 RAM, ROM, and flash memory devices.
1960 Erase and program a flash memory device.
1962 * Removed remote packets
1965 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1966 used it, and only gdbserver implemented it.
1968 *** Changes in GDB 6.5
1972 Renesas M32C/M16C m32c-elf
1974 Morpho Technologies ms1 ms1-elf
1978 init-if-undefined Initialize a convenience variable, but
1979 only if it doesn't already have a value.
1981 The following commands are presently only implemented for native GNU/Linux:
1983 checkpoint Save a snapshot of the program state.
1985 restart <n> Return the program state to a
1986 previously saved state.
1988 info checkpoints List currently saved checkpoints.
1990 delete-checkpoint <n> Delete a previously saved checkpoint.
1992 set|show detach-on-fork Tell gdb whether to detach from a newly
1993 forked process, or to keep debugging it.
1995 info forks List forks of the user program that
1996 are available to be debugged.
1998 fork <n> Switch to debugging one of several
1999 forks of the user program that are
2000 available to be debugged.
2002 delete-fork <n> Delete a fork from the list of forks
2003 that are available to be debugged (and
2004 kill the forked process).
2006 detach-fork <n> Delete a fork from the list of forks
2007 that are available to be debugged (and
2008 allow the process to continue).
2012 Morpho Technologies ms2 ms1-elf
2014 * Improved Windows host support
2016 GDB now builds as a cross debugger hosted on i686-mingw32, including
2017 native console support, and remote communications using either
2018 network sockets or serial ports.
2020 * Improved Modula-2 language support
2022 GDB can now print most types in the Modula-2 syntax. This includes:
2023 basic types, set types, record types, enumerated types, range types,
2024 pointer types and ARRAY types. Procedure var parameters are correctly
2025 printed and hexadecimal addresses and character constants are also
2026 written in the Modula-2 syntax. Best results can be obtained by using
2027 GNU Modula-2 together with the -gdwarf-2 command line option.
2031 The ARM rdi-share module.
2033 The Netware NLM debug server.
2035 *** Changes in GDB 6.4
2037 * New native configurations
2039 OpenBSD/arm arm*-*-openbsd*
2040 OpenBSD/mips64 mips64-*-openbsd*
2044 Morpho Technologies ms1 ms1-elf
2046 * New command line options
2048 --batch-silent As for --batch, but totally silent.
2049 --return-child-result The debugger will exist with the same value
2050 the child (debugged) program exited with.
2051 --eval-command COMMAND, -ex COMMAND
2052 Execute a single GDB CLI command. This may be
2053 specified multiple times and in conjunction
2054 with the --command (-x) option.
2056 * Deprecated commands removed
2058 The following commands, that were deprecated in 2000, have been
2062 set|show arm disassembly-flavor set|show arm disassembler
2063 othernames set arm disassembler
2064 set|show remotedebug set|show debug remote
2065 set|show archdebug set|show debug arch
2066 set|show eventdebug set|show debug event
2069 * New BSD user-level threads support
2071 It is now possible to debug programs using the user-level threads
2072 library on OpenBSD and FreeBSD. Currently supported (target)
2075 FreeBSD/amd64 x86_64-*-freebsd*
2076 FreeBSD/i386 i386-*-freebsd*
2077 OpenBSD/i386 i386-*-openbsd*
2079 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2080 are not yet supported.
2082 * New support for Matsushita MN10300 w/sim added
2083 (Work in progress). mn10300-elf.
2085 * REMOVED configurations and files
2087 VxWorks and the XDR protocol *-*-vxworks
2088 Motorola MCORE mcore-*-*
2089 National Semiconductor NS32000 ns32k-*-*
2091 * New "set print array-indexes" command
2093 After turning this setting "on", GDB prints the index of each element
2094 when displaying arrays. The default is "off" to preserve the previous
2097 * VAX floating point support
2099 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2101 * User-defined command support
2103 In addition to using $arg0..$arg9 for argument passing, it is now possible
2104 to use $argc to determine now many arguments have been passed. See the
2105 section on user-defined commands in the user manual for more information.
2107 *** Changes in GDB 6.3:
2109 * New command line option
2111 GDB now accepts -l followed by a number to set the timeout for remote
2114 * GDB works with GCC -feliminate-dwarf2-dups
2116 GDB now supports a more compact representation of DWARF-2 debug
2117 information using DW_FORM_ref_addr references. These are produced
2118 by GCC with the option -feliminate-dwarf2-dups and also by some
2119 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2120 to use -feliminate-dwarf2-dups.
2122 * Internationalization
2124 When supported by the host system, GDB will be built with
2125 internationalization (libintl). The task of marking up the sources is
2126 continued, we're looking forward to our first translation.
2130 Initial support for debugging programs compiled with the GNAT
2131 implementation of the Ada programming language has been integrated
2132 into GDB. In this release, support is limited to expression evaluation.
2134 * New native configurations
2136 GNU/Linux/m32r m32r-*-linux-gnu
2140 GDB's remote protocol now includes support for the 'p' packet. This
2141 packet is used to fetch individual registers from a remote inferior.
2143 * END-OF-LIFE registers[] compatibility module
2145 GDB's internal register infrastructure has been completely rewritten.
2146 The new infrastructure making possible the implementation of key new
2147 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2150 GDB 6.3 will be the last release to include the the registers[]
2151 compatibility module that allowed out-of-date configurations to
2152 continue to work. This change directly impacts the following
2162 powerpc bdm protocol
2164 Unless there is activity to revive these configurations, they will be
2165 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2167 * OBSOLETE configurations and files
2169 Configurations that have been declared obsolete in this release have
2170 been commented out. Unless there is activity to revive these
2171 configurations, the next release of GDB will have their sources
2172 permanently REMOVED.
2181 *** Changes in GDB 6.2.1:
2183 * MIPS `break main; run' gave an heuristic-fence-post warning
2185 When attempting to run even a simple program, a warning about
2186 heuristic-fence-post being hit would be reported. This problem has
2189 * MIPS IRIX 'long double' crashed GDB
2191 When examining a long double variable, GDB would get a segmentation
2192 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2193 IRIX long double values).
2197 A bug in the VAX stack code was causing problems with the "next"
2198 command. This problem has been fixed.
2200 *** Changes in GDB 6.2:
2202 * Fix for ``many threads''
2204 On GNU/Linux systems that use the NPTL threads library, a program
2205 rapidly creating and deleting threads would confuse GDB leading to the
2208 ptrace: No such process.
2209 thread_db_get_info: cannot get thread info: generic error
2211 This problem has been fixed.
2213 * "-async" and "-noasync" options removed.
2215 Support for the broken "-noasync" option has been removed (it caused
2218 * New ``start'' command.
2220 This command runs the program until the begining of the main procedure.
2222 * New BSD Kernel Data Access Library (libkvm) interface
2224 Using ``target kvm'' it is now possible to debug kernel core dumps and
2225 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2226 platforms. Currently supported (native-only) configurations are:
2228 FreeBSD/amd64 x86_64-*-freebsd*
2229 FreeBSD/i386 i?86-*-freebsd*
2230 NetBSD/i386 i?86-*-netbsd*
2231 NetBSD/m68k m68*-*-netbsd*
2232 NetBSD/sparc sparc-*-netbsd*
2233 OpenBSD/amd64 x86_64-*-openbsd*
2234 OpenBSD/i386 i?86-*-openbsd*
2235 OpenBSD/m68k m68*-openbsd*
2236 OpenBSD/sparc sparc-*-openbsd*
2238 * Signal trampoline code overhauled
2240 Many generic problems with GDB's signal handling code have been fixed.
2241 These include: backtraces through non-contiguous stacks; recognition
2242 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2243 call; backtrace through a signal trampoline; step into and out of
2244 signal handlers; and single-stepping in the signal trampoline.
2246 Please note that kernel bugs are a limiting factor here. These
2247 features have been shown to work on an s390 GNU/Linux system that
2248 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2250 * Cygwin support for DWARF 2 added.
2252 * New native configurations
2254 GNU/Linux/hppa hppa*-*-linux*
2255 OpenBSD/hppa hppa*-*-openbsd*
2256 OpenBSD/m68k m68*-*-openbsd*
2257 OpenBSD/m88k m88*-*-openbsd*
2258 OpenBSD/powerpc powerpc-*-openbsd*
2259 NetBSD/vax vax-*-netbsd*
2260 OpenBSD/vax vax-*-openbsd*
2262 * END-OF-LIFE frame compatibility module
2264 GDB's internal frame infrastructure has been completely rewritten.
2265 The new infrastructure making it possible to support key new features
2266 including DWARF 2 Call Frame Information. To aid in the task of
2267 migrating old configurations to this new infrastructure, a
2268 compatibility module, that allowed old configurations to continue to
2269 work, was also included.
2271 GDB 6.2 will be the last release to include this frame compatibility
2272 module. This change directly impacts the following configurations:
2282 Unless there is activity to revive these configurations, they will be
2283 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2285 * REMOVED configurations and files
2287 Sun 3, running SunOS 3 m68*-*-sunos3*
2288 Sun 3, running SunOS 4 m68*-*-sunos4*
2289 Sun 2, running SunOS 3 m68000-*-sunos3*
2290 Sun 2, running SunOS 4 m68000-*-sunos4*
2291 Motorola 680x0 running LynxOS m68*-*-lynxos*
2292 AT&T 3b1/Unix pc m68*-att-*
2293 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2294 decstation mips-dec-* mips-little-*
2295 riscos mips-*-riscos* mips-*-sysv*
2296 sonymips mips-sony-*
2297 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2299 *** Changes in GDB 6.1.1:
2301 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2303 The TUI (Text-mode User Interface) is now built as part of a default
2304 GDB configuration. It is enabled by either selecting the TUI with the
2305 command line option "-i=tui" or by running the separate "gdbtui"
2306 program. For more information on the TUI, see the manual "Debugging
2309 * Pending breakpoint support (also included in GDB 6.1)
2311 Support has been added to allow you to specify breakpoints in shared
2312 libraries that have not yet been loaded. If a breakpoint location
2313 cannot be found, and the "breakpoint pending" option is set to auto,
2314 GDB queries you if you wish to make the breakpoint pending on a future
2315 shared-library load. If and when GDB resolves the breakpoint symbol,
2316 the pending breakpoint is removed as one or more regular breakpoints
2319 Pending breakpoints are very useful for GCJ Java debugging.
2321 * Fixed ISO-C build problems
2323 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2324 non ISO-C code that stopped them being built using a more strict ISO-C
2325 compiler (e.g., IBM's C compiler).
2327 * Fixed build problem on IRIX 5
2329 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2330 wasn't able to compile compile on an IRIX 5 system.
2332 * Added execute permission to gdb/gdbserver/configure
2334 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2335 permission. This bug would cause configure to fail on a number of
2336 systems (Solaris, IRIX). Ref: server/519.
2338 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2340 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2341 has been updated to use constant array sizes.
2343 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2345 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2346 its generated DWARF Call Frame Info. This encoding was causing GDB to
2347 panic, that panic has been fixed. Ref: gdb/1628.
2349 * Fixed a problem when examining parameters in shared library code.
2351 When examining parameters in optimized shared library code generated
2352 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2353 not available''. GDB now correctly displays the variable's value.
2355 *** Changes in GDB 6.1:
2357 * Removed --with-mmalloc
2359 Support for the mmalloc memory manager has been removed, as it
2360 conflicted with the internal gdb byte cache.
2362 * Changes in AMD64 configurations
2364 The AMD64 target now includes the %cs and %ss registers. As a result
2365 the AMD64 remote protocol has changed; this affects the floating-point
2366 and SSE registers. If you rely on those registers for your debugging,
2367 you should upgrade gdbserver on the remote side.
2369 * Revised SPARC target
2371 The SPARC target has been completely revised, incorporating the
2372 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2373 support for LynxOS and SunOS 4 has been dropped. Calling functions
2374 from within GDB on operating systems with a non-executable stack
2375 (Solaris, OpenBSD) now works.
2379 GDB has a new C++ demangler which does a better job on the mangled
2380 names generated by current versions of g++. It also runs faster, so
2381 with this and other changes gdb should now start faster on large C++
2384 * DWARF 2 Location Expressions
2386 GDB support for location expressions has been extended to support function
2387 arguments and frame bases. Older versions of GDB could crash when they
2390 * C++ nested types and namespaces
2392 GDB's support for nested types and namespaces in C++ has been
2393 improved, especially if you use the DWARF 2 debugging format. (This
2394 is the default for recent versions of GCC on most platforms.)
2395 Specifically, if you have a class "Inner" defined within a class or
2396 namespace "Outer", then GDB realizes that the class's name is
2397 "Outer::Inner", not simply "Inner". This should greatly reduce the
2398 frequency of complaints about not finding RTTI symbols. In addition,
2399 if you are stopped at inside of a function defined within a namespace,
2400 GDB modifies its name lookup accordingly.
2402 * New native configurations
2404 NetBSD/amd64 x86_64-*-netbsd*
2405 OpenBSD/amd64 x86_64-*-openbsd*
2406 OpenBSD/alpha alpha*-*-openbsd*
2407 OpenBSD/sparc sparc-*-openbsd*
2408 OpenBSD/sparc64 sparc64-*-openbsd*
2410 * New debugging protocols
2412 M32R with SDI protocol m32r-*-elf*
2414 * "set prompt-escape-char" command deleted.
2416 The command "set prompt-escape-char" has been deleted. This command,
2417 and its very obscure effet on GDB's prompt, was never documented,
2418 tested, nor mentioned in the NEWS file.
2420 * OBSOLETE configurations and files
2422 Configurations that have been declared obsolete in this release have
2423 been commented out. Unless there is activity to revive these
2424 configurations, the next release of GDB will have their sources
2425 permanently REMOVED.
2427 Sun 3, running SunOS 3 m68*-*-sunos3*
2428 Sun 3, running SunOS 4 m68*-*-sunos4*
2429 Sun 2, running SunOS 3 m68000-*-sunos3*
2430 Sun 2, running SunOS 4 m68000-*-sunos4*
2431 Motorola 680x0 running LynxOS m68*-*-lynxos*
2432 AT&T 3b1/Unix pc m68*-att-*
2433 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2434 decstation mips-dec-* mips-little-*
2435 riscos mips-*-riscos* mips-*-sysv*
2436 sonymips mips-sony-*
2437 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2439 * REMOVED configurations and files
2441 SGI Irix-4.x mips-sgi-irix4 or iris4
2442 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2443 Z8000 simulator z8k-zilog-none or z8ksim
2444 Matsushita MN10200 w/simulator mn10200-*-*
2445 H8/500 simulator h8500-hitachi-hms or h8500hms
2446 HP/PA running BSD hppa*-*-bsd*
2447 HP/PA running OSF/1 hppa*-*-osf*
2448 HP/PA Pro target hppa*-*-pro*
2449 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2450 386BSD i[3456]86-*-bsd*
2451 Sequent family i[3456]86-sequent-sysv4*
2452 i[3456]86-sequent-sysv*
2453 i[3456]86-sequent-bsd*
2454 SPARC running LynxOS sparc-*-lynxos*
2455 SPARC running SunOS 4 sparc-*-sunos4*
2456 Tsqware Sparclet sparclet-*-*
2457 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2459 *** Changes in GDB 6.0:
2463 Support for debugging the Objective-C programming language has been
2464 integrated into GDB.
2466 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2468 DWARF 2's Call Frame Information makes available compiler generated
2469 information that more exactly describes the program's run-time stack.
2470 By using this information, GDB is able to provide more robust stack
2473 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2474 have been updated to use a new backtrace mechanism which includes
2475 DWARF 2 CFI support.
2479 GDB's remote protocol has been extended to include support for hosted
2480 file I/O (where the remote target uses GDB's file system). See GDB's
2481 remote protocol documentation for details.
2483 * All targets using the new architecture framework.
2485 All of GDB's targets have been updated to use the new internal
2486 architecture framework. The way is now open for future GDB releases
2487 to include cross-architecture native debugging support (i386 on amd64,
2490 * GNU/Linux's Thread Local Storage (TLS)
2492 GDB now includes support for for the GNU/Linux implementation of
2493 per-thread variables.
2495 * GNU/Linux's Native POSIX Thread Library (NPTL)
2497 GDB's thread code has been updated to work with either the new
2498 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2500 * Separate debug info.
2502 GDB, in conjunction with BINUTILS, now supports a mechanism for
2503 automatically loading debug information from a separate file. Instead
2504 of shipping full debug and non-debug versions of system libraries,
2505 system integrators can now instead ship just the stripped libraries
2506 and optional debug files.
2508 * DWARF 2 Location Expressions
2510 DWARF 2 Location Expressions allow the compiler to more completely
2511 describe the location of variables (even in optimized code) to the
2514 GDB now includes preliminary support for location expressions (support
2515 for DW_OP_piece is still missing).
2519 A number of long standing bugs that caused GDB to die while starting a
2520 Java application have been fixed. GDB's Java support is now
2521 considered "useable".
2523 * GNU/Linux support for fork, vfork, and exec.
2525 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2526 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2529 * GDB supports logging output to a file
2531 There are two new commands, "set logging" and "show logging", which can be
2532 used to capture GDB's output to a file.
2534 * The meaning of "detach" has changed for gdbserver
2536 The "detach" command will now resume the application, as documented. To
2537 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2540 * d10v, m68hc11 `regs' command deprecated
2542 The `info registers' command has been updated so that it displays the
2543 registers using a format identical to the old `regs' command.
2547 A new command, "maint set profile on/off", has been added. This command can
2548 be used to enable or disable profiling while running GDB, to profile a
2549 session or a set of commands. In addition there is a new configure switch,
2550 "--enable-profiling", which will cause GDB to be compiled with profiling
2551 data, for more informative profiling results.
2553 * Default MI syntax changed to "mi2".
2555 The default MI (machine interface) syntax, enabled by the command line
2556 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2557 "mi1", can be enabled by specifying the option "-i=mi1".
2559 Support for the original "mi0" syntax (included in GDB 5.0) has been
2562 Fix for gdb/192: removed extraneous space when displaying frame level.
2563 Fix for gdb/672: update changelist is now output in mi list format.
2564 Fix for gdb/702: a -var-assign that updates the value now shows up
2565 in a subsequent -var-update.
2567 * New native configurations.
2569 FreeBSD/amd64 x86_64-*-freebsd*
2571 * Multi-arched targets.
2573 HP/PA HPUX11 hppa*-*-hpux*
2574 Renesas M32R/D w/simulator m32r-*-elf*
2576 * OBSOLETE configurations and files
2578 Configurations that have been declared obsolete in this release have
2579 been commented out. Unless there is activity to revive these
2580 configurations, the next release of GDB will have their sources
2581 permanently REMOVED.
2583 Z8000 simulator z8k-zilog-none or z8ksim
2584 Matsushita MN10200 w/simulator mn10200-*-*
2585 H8/500 simulator h8500-hitachi-hms or h8500hms
2586 HP/PA running BSD hppa*-*-bsd*
2587 HP/PA running OSF/1 hppa*-*-osf*
2588 HP/PA Pro target hppa*-*-pro*
2589 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2590 Sequent family i[3456]86-sequent-sysv4*
2591 i[3456]86-sequent-sysv*
2592 i[3456]86-sequent-bsd*
2593 Tsqware Sparclet sparclet-*-*
2594 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2596 * REMOVED configurations and files
2599 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2600 IBM AIX PS/2 i[3456]86-*-aix
2601 i386 running Mach 3.0 i[3456]86-*-mach3*
2602 i386 running Mach i[3456]86-*-mach*
2603 i386 running OSF/1 i[3456]86-*osf1mk*
2604 HP/Apollo 68k Family m68*-apollo*-sysv*,
2606 m68*-hp-bsd*, m68*-hp-hpux*
2607 Argonaut Risc Chip (ARC) arc-*-*
2608 Mitsubishi D30V d30v-*-*
2609 Fujitsu FR30 fr30-*-elf*
2610 OS/9000 i[34]86-*-os9k
2611 I960 with MON960 i960-*-coff
2613 * MIPS $fp behavior changed
2615 The convenience variable $fp, for the MIPS, now consistently returns
2616 the address of the current frame's base. Previously, depending on the
2617 context, $fp could refer to either $sp or the current frame's base
2618 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2619 The GNU Source-Level Debugger''.
2621 *** Changes in GDB 5.3:
2623 * GNU/Linux shared library multi-threaded performance improved.
2625 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2626 `/proc', in preference to `ptrace' for memory reads. This may result
2627 in an improvement in the start-up time of multi-threaded, shared
2628 library applications when run under GDB. One GDB user writes: ``loads
2629 shared libs like mad''.
2631 * ``gdbserver'' now supports multi-threaded applications on some targets
2633 Support for debugging multi-threaded applications which use
2634 the GNU/Linux LinuxThreads package has been added for
2635 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2636 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2638 * GDB now supports C/C++ preprocessor macros.
2640 GDB now expands preprocessor macro invocations in C/C++ expressions,
2641 and provides various commands for showing macro definitions and how
2644 The new command `macro expand EXPRESSION' expands any macro
2645 invocations in expression, and shows the result.
2647 The new command `show macro MACRO-NAME' shows the definition of the
2648 macro named MACRO-NAME, and where it was defined.
2650 Most compilers don't include information about macros in the debugging
2651 information by default. In GCC 3.1, for example, you need to compile
2652 your program with the options `-gdwarf-2 -g3'. If the macro
2653 information is present in the executable, GDB will read it.
2655 * Multi-arched targets.
2657 DEC Alpha (partial) alpha*-*-*
2658 DEC VAX (partial) vax-*-*
2660 National Semiconductor NS32000 (partial) ns32k-*-*
2661 Motorola 68000 (partial) m68k-*-*
2662 Motorola MCORE mcore-*-*
2666 Fujitsu FRV architecture added by Red Hat frv*-*-*
2669 * New native configurations
2671 Alpha NetBSD alpha*-*-netbsd*
2672 SH NetBSD sh*-*-netbsdelf*
2673 MIPS NetBSD mips*-*-netbsd*
2674 UltraSPARC NetBSD sparc64-*-netbsd*
2676 * OBSOLETE configurations and files
2678 Configurations that have been declared obsolete in this release have
2679 been commented out. Unless there is activity to revive these
2680 configurations, the next release of GDB will have their sources
2681 permanently REMOVED.
2683 Mitsubishi D30V d30v-*-*
2684 OS/9000 i[34]86-*-os9k
2685 IBM AIX PS/2 i[3456]86-*-aix
2686 Fujitsu FR30 fr30-*-elf*
2687 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2688 Argonaut Risc Chip (ARC) arc-*-*
2689 i386 running Mach 3.0 i[3456]86-*-mach3*
2690 i386 running Mach i[3456]86-*-mach*
2691 i386 running OSF/1 i[3456]86-*osf1mk*
2692 HP/Apollo 68k Family m68*-apollo*-sysv*,
2694 m68*-hp-bsd*, m68*-hp-hpux*
2695 I960 with MON960 i960-*-coff
2697 * OBSOLETE languages
2699 CHILL, a Pascal like language used by telecommunications companies.
2701 * REMOVED configurations and files
2703 AMD 29k family via UDI a29k-amd-udi, udi29k
2704 A29K VxWorks a29k-*-vxworks
2705 AMD 29000 embedded, using EBMON a29k-none-none
2706 AMD 29000 embedded with COFF a29k-none-coff
2707 AMD 29000 embedded with a.out a29k-none-aout
2709 testsuite/gdb.hp/gdb.threads-hp/ directory
2711 * New command "set max-user-call-depth <nnn>"
2713 This command allows the user to limit the call depth of user-defined
2714 commands. The default is 1024.
2716 * Changes in FreeBSD/i386 native debugging.
2718 Support for the "generate-core-file" has been added.
2720 * New commands "dump", "append", and "restore".
2722 These commands allow data to be copied from target memory
2723 to a bfd-format or binary file (dump and append), and back
2724 from a file into memory (restore).
2726 * Improved "next/step" support on multi-processor Alpha Tru64.
2728 The previous single-step mechanism could cause unpredictable problems,
2729 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2730 of a software single-step mechanism prevents this.
2732 *** Changes in GDB 5.2.1:
2740 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2741 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2742 Fix, by Joel Brobecker imported from mainline.
2744 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2745 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2746 Fix, by Fred Fish, imported from mainline.
2748 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2749 Surprisingly enough, it works now.
2750 By Michal Ludvig, imported from mainline.
2752 i386 hardware watchpoint support:
2753 avoid misses on second run for some targets.
2754 By Pierre Muller, imported from mainline.
2756 *** Changes in GDB 5.2:
2758 * New command "set trust-readonly-sections on[off]".
2760 This command is a hint that tells gdb that read-only sections
2761 really are read-only (ie. that their contents will not change).
2762 In this mode, gdb will go to the object file rather than the
2763 target to read memory from read-only sections (such as ".text").
2764 This can be a significant performance improvement on some
2765 (notably embedded) targets.
2767 * New command "generate-core-file" (or "gcore").
2769 This new gdb command allows the user to drop a core file of the child
2770 process state at any time. So far it's been implemented only for
2771 GNU/Linux and Solaris, but should be relatively easily ported to other
2772 hosts. Argument is core file name (defaults to core.<pid>).
2774 * New command line option
2776 GDB now accepts --pid or -p followed by a process id.
2778 * Change in command line behavior -- corefiles vs. process ids.
2780 There is a subtle behavior in the way in which GDB handles
2781 command line arguments. The first non-flag argument is always
2782 a program to debug, but the second non-flag argument may either
2783 be a corefile or a process id. Previously, GDB would attempt to
2784 open the second argument as a corefile, and if that failed, would
2785 issue a superfluous error message and then attempt to attach it as
2786 a process. Now, if the second argument begins with a non-digit,
2787 it will be treated as a corefile. If it begins with a digit,
2788 GDB will attempt to attach it as a process, and if no such process
2789 is found, will then attempt to open it as a corefile.
2791 * Changes in ARM configurations.
2793 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2794 configuration is fully multi-arch.
2796 * New native configurations
2798 ARM NetBSD arm*-*-netbsd*
2799 x86 OpenBSD i[3456]86-*-openbsd*
2800 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2801 Sparc64 running FreeBSD sparc64-*-freebsd*
2805 Sanyo XStormy16 xstormy16-elf
2807 * OBSOLETE configurations and files
2809 Configurations that have been declared obsolete in this release have
2810 been commented out. Unless there is activity to revive these
2811 configurations, the next release of GDB will have their sources
2812 permanently REMOVED.
2814 AMD 29k family via UDI a29k-amd-udi, udi29k
2815 A29K VxWorks a29k-*-vxworks
2816 AMD 29000 embedded, using EBMON a29k-none-none
2817 AMD 29000 embedded with COFF a29k-none-coff
2818 AMD 29000 embedded with a.out a29k-none-aout
2820 testsuite/gdb.hp/gdb.threads-hp/ directory
2822 * REMOVED configurations and files
2824 TI TMS320C80 tic80-*-*
2826 PowerPC Solaris powerpcle-*-solaris*
2827 PowerPC Windows NT powerpcle-*-cygwin32
2828 PowerPC Netware powerpc-*-netware*
2829 Harris/CXUX m88k m88*-harris-cxux*
2830 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2831 ns32k-utek-sysv* ns32k-utek-*
2832 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2833 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2834 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2835 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2836 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2838 * Changes to command line processing
2840 The new `--args' feature can be used to specify command-line arguments
2841 for the inferior from gdb's command line.
2843 * Changes to key bindings
2845 There is a new `operate-and-get-next' function bound to `C-o'.
2847 *** Changes in GDB 5.1.1
2849 Fix compile problem on DJGPP.
2851 Fix a problem with floating-point registers on the i386 being
2854 Fix to stop GDB crashing on .debug_str debug info.
2856 Numerous documentation fixes.
2858 Numerous testsuite fixes.
2860 *** Changes in GDB 5.1:
2862 * New native configurations
2864 Alpha FreeBSD alpha*-*-freebsd*
2865 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2866 MIPS GNU/Linux mips*-*-linux*
2867 MIPS SGI Irix 6.x mips*-sgi-irix6*
2868 ia64 AIX ia64-*-aix*
2869 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2873 Motorola 68HC11 and 68HC12 m68hc11-elf
2875 UltraSparc running GNU/Linux sparc64-*-linux*
2877 * OBSOLETE configurations and files
2879 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2880 Harris/CXUX m88k m88*-harris-cxux*
2881 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2882 ns32k-utek-sysv* ns32k-utek-*
2883 TI TMS320C80 tic80-*-*
2885 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2886 PowerPC Solaris powerpcle-*-solaris*
2887 PowerPC Windows NT powerpcle-*-cygwin32
2888 PowerPC Netware powerpc-*-netware*
2889 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2890 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2891 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2892 Apple Macintosh (MPW) host N/A
2894 stuff.c (Program to stuff files into a specially prepared space in kdb)
2895 kdb-start.c (Main loop for the standalone kernel debugger)
2897 Configurations that have been declared obsolete in this release have
2898 been commented out. Unless there is activity to revive these
2899 configurations, the next release of GDB will have their sources
2900 permanently REMOVED.
2902 * REMOVED configurations and files
2904 Altos 3068 m68*-altos-*
2905 Convex c1-*-*, c2-*-*
2907 ARM RISCix arm-*-* (as host)
2911 * GDB has been converted to ISO C.
2913 GDB's source code has been converted to ISO C. In particular, the
2914 sources are fully protoized, and rely on standard headers being
2919 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2921 * The MI enabled by default.
2923 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2924 revised and enabled by default. Packages which use GDB as a debugging
2925 engine behind a UI or another front end are encouraged to switch to
2926 using the GDB/MI interface, instead of the old annotations interface
2927 which is now deprecated.
2929 * Support for debugging Pascal programs.
2931 GDB now includes support for debugging Pascal programs. The following
2932 main features are supported:
2934 - Pascal-specific data types such as sets;
2936 - automatic recognition of Pascal sources based on file-name
2939 - Pascal-style display of data types, variables, and functions;
2941 - a Pascal expression parser.
2943 However, some important features are not yet supported.
2945 - Pascal string operations are not supported at all;
2947 - there are some problems with boolean types;
2949 - Pascal type hexadecimal constants are not supported
2950 because they conflict with the internal variables format;
2952 - support for Pascal objects and classes is not full yet;
2954 - unlike Pascal, GDB is case-sensitive for symbol names.
2956 * Changes in completion.
2958 Commands such as `shell', `run' and `set args', which pass arguments
2959 to inferior programs, now complete on file names, similar to what
2960 users expect at the shell prompt.
2962 Commands which accept locations, such as `disassemble', `print',
2963 `breakpoint', `until', etc. now complete on filenames as well as
2964 program symbols. Thus, if you type "break foob TAB", and the source
2965 files linked into the programs include `foobar.c', that file name will
2966 be one of the candidates for completion. However, file names are not
2967 considered for completion after you typed a colon that delimits a file
2968 name from a name of a function in that file, as in "break foo.c:bar".
2970 `set demangle-style' completes on available demangling styles.
2972 * New platform-independent commands:
2974 It is now possible to define a post-hook for a command as well as a
2975 hook that runs before the command. For more details, see the
2976 documentation of `hookpost' in the GDB manual.
2978 * Changes in GNU/Linux native debugging.
2980 Support for debugging multi-threaded programs has been completely
2981 revised for all platforms except m68k and sparc. You can now debug as
2982 many threads as your system allows you to have.
2984 Attach/detach is supported for multi-threaded programs.
2986 Support for SSE registers was added for x86. This doesn't work for
2987 multi-threaded programs though.
2989 * Changes in MIPS configurations.
2991 Multi-arch support is enabled for all MIPS configurations.
2993 GDB can now be built as native debugger on SGI Irix 6.x systems for
2994 debugging n32 executables. (Debugging 64-bit executables is not yet
2997 * Unified support for hardware watchpoints in all x86 configurations.
2999 Most (if not all) native x86 configurations support hardware-assisted
3000 breakpoints and watchpoints in a unified manner. This support
3001 implements debug register sharing between watchpoints, which allows to
3002 put a virtually infinite number of watchpoints on the same address,
3003 and also supports watching regions up to 16 bytes with several debug
3006 The new maintenance command `maintenance show-debug-regs' toggles
3007 debugging print-outs in functions that insert, remove, and test
3008 watchpoints and hardware breakpoints.
3010 * Changes in the DJGPP native configuration.
3012 New command ``info dos sysinfo'' displays assorted information about
3013 the CPU, OS, memory, and DPMI server.
3015 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3016 display information about segment descriptors stored in GDT, LDT, and
3019 New commands ``info dos pde'' and ``info dos pte'' display entries
3020 from Page Directory and Page Tables (for now works with CWSDPMI only).
3021 New command ``info dos address-pte'' displays the Page Table entry for
3022 a given linear address.
3024 GDB can now pass command lines longer than 126 characters to the
3025 program being debugged (requires an update to the libdbg.a library
3026 which is part of the DJGPP development kit).
3028 DWARF2 debug info is now supported.
3030 It is now possible to `step' and `next' through calls to `longjmp'.
3032 * Changes in documentation.
3034 All GDB documentation was converted to GFDL, the GNU Free
3035 Documentation License.
3037 Tracepoints-related commands are now fully documented in the GDB
3040 TUI, the Text-mode User Interface, is now documented in the manual.
3042 Tracepoints-related commands are now fully documented in the GDB
3045 The "GDB Internals" manual now has an index. It also includes
3046 documentation of `ui_out' functions, GDB coding standards, x86
3047 hardware watchpoints, and memory region attributes.
3049 * GDB's version number moved to ``version.in''
3051 The Makefile variable VERSION has been replaced by the file
3052 ``version.in''. People creating GDB distributions should update the
3053 contents of this file.
3057 GUD support is now a standard part of the EMACS distribution.
3059 *** Changes in GDB 5.0:
3061 * Improved support for debugging FP programs on x86 targets
3063 Unified and much-improved support for debugging floating-point
3064 programs on all x86 targets. In particular, ``info float'' now
3065 displays the FP registers in the same format on all x86 targets, with
3066 greater level of detail.
3068 * Improvements and bugfixes in hardware-assisted watchpoints
3070 It is now possible to watch array elements, struct members, and
3071 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3072 on x86 targets no longer erroneously trigger when the address is
3075 * Improvements in the native DJGPP version of GDB
3077 The distribution now includes all the scripts and auxiliary files
3078 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3079 machines ``out of the box''.
3081 The DJGPP version can now debug programs that use signals. It is
3082 possible to catch signals that happened in the debuggee, deliver
3083 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3084 would kill the program being debugged.) Programs that hook hardware
3085 interrupts (keyboard, timer, etc.) can also be debugged.
3087 It is now possible to debug DJGPP programs that redirect their
3088 standard handles or switch them to raw (as opposed to cooked) mode, or
3089 even close them. The command ``run < foo > bar'' works as expected,
3090 and ``info terminal'' reports useful information about the debuggee's
3091 terminal, including raw/cooked mode, redirection, etc.
3093 The DJGPP version now uses termios functions for console I/O, which
3094 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3097 DOS-style file names with drive letters are now fully supported by
3100 It is now possible to debug DJGPP programs that switch their working
3101 directory. It is also possible to rerun the debuggee any number of
3102 times without restarting GDB; thus, you can use the same setup,
3103 breakpoints, etc. for many debugging sessions.
3105 * New native configurations
3107 ARM GNU/Linux arm*-*-linux*
3108 PowerPC GNU/Linux powerpc-*-linux*
3112 Motorola MCore mcore-*-*
3113 x86 VxWorks i[3456]86-*-vxworks*
3114 PowerPC VxWorks powerpc-*-vxworks*
3115 TI TMS320C80 tic80-*-*
3117 * OBSOLETE configurations
3119 Altos 3068 m68*-altos-*
3120 Convex c1-*-*, c2-*-*
3122 ARM RISCix arm-*-* (as host)
3125 Configurations that have been declared obsolete will be commented out,
3126 but the code will be left in place. If there is no activity to revive
3127 these configurations before the next release of GDB, the sources will
3128 be permanently REMOVED.
3130 * Gould support removed
3132 Support for the Gould PowerNode and NP1 has been removed.
3134 * New features for SVR4
3136 On SVR4 native platforms (such as Solaris), if you attach to a process
3137 without first loading a symbol file, GDB will now attempt to locate and
3138 load symbols from the running process's executable file.
3140 * Many C++ enhancements
3142 C++ support has been greatly improved. Overload resolution now works properly
3143 in almost all cases. RTTI support is on the way.
3145 * Remote targets can connect to a sub-program
3147 A popen(3) style serial-device has been added. This device starts a
3148 sub-process (such as a stand-alone simulator) and then communicates
3149 with that. The sub-program to run is specified using the syntax
3150 ``|<program> <args>'' vis:
3152 (gdb) set remotedebug 1
3153 (gdb) target extended-remote |mn10300-elf-sim program-args
3155 * MIPS 64 remote protocol
3157 A long standing bug in the mips64 remote protocol where by GDB
3158 expected certain 32 bit registers (ex SR) to be transfered as 32
3159 instead of 64 bits has been fixed.
3161 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3162 added to provide backward compatibility with older versions of GDB.
3164 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3166 The command ``set remotebinarydownload'' command has been replaced by
3167 ``set remote X-packet''. Other commands in ``set remote'' family
3168 include ``set remote P-packet''.
3170 * Breakpoint commands accept ranges.
3172 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3173 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3174 ``tracepoint passcount'' also accepts a range of tracepoints.
3176 * ``apropos'' command added.
3178 The ``apropos'' command searches through command names and
3179 documentation strings, printing out matches, making it much easier to
3180 try to find a command that does what you are looking for.
3184 A new machine oriented interface (MI) has been added to GDB. This
3185 interface is designed for debug environments running GDB as a separate
3186 process. This is part of the long term libGDB project. See the
3187 "GDB/MI" chapter of the GDB manual for further information. It can be
3188 enabled by configuring with:
3190 .../configure --enable-gdbmi
3192 *** Changes in GDB-4.18:
3194 * New native configurations
3196 HP-UX 10.20 hppa*-*-hpux10.20
3197 HP-UX 11.x hppa*-*-hpux11.0*
3198 M68K GNU/Linux m68*-*-linux*
3202 Fujitsu FR30 fr30-*-elf*
3203 Intel StrongARM strongarm-*-*
3204 Mitsubishi D30V d30v-*-*
3206 * OBSOLETE configurations
3208 Gould PowerNode, NP1 np1-*-*, pn-*-*
3210 Configurations that have been declared obsolete will be commented out,
3211 but the code will be left in place. If there is no activity to revive
3212 these configurations before the next release of GDB, the sources will
3213 be permanently REMOVED.
3217 As a compatibility experiment, GDB's source files buildsym.h and
3218 buildsym.c have been converted to pure standard C, no longer
3219 containing any K&R compatibility code. We believe that all systems in
3220 use today either come with a standard C compiler, or have a GCC port
3221 available. If this is not true, please report the affected
3222 configuration to bug-gdb@gnu.org immediately. See the README file for
3223 information about getting a standard C compiler if you don't have one
3228 GDB now uses readline 2.2.
3230 * set extension-language
3232 You can now control the mapping between filename extensions and source
3233 languages by using the `set extension-language' command. For instance,
3234 you can ask GDB to treat .c files as C++ by saying
3235 set extension-language .c c++
3236 The command `info extensions' lists all of the recognized extensions
3237 and their associated languages.
3239 * Setting processor type for PowerPC and RS/6000
3241 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3242 you can use the `set processor' command to specify what variant of the
3243 PowerPC family you are debugging. The command
3247 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3248 following PowerPC and RS6000 variants:
3250 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3251 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3253 403GC IBM PowerPC 403GC
3254 505 Motorola PowerPC 505
3255 860 Motorola PowerPC 860 or 850
3256 601 Motorola PowerPC 601
3257 602 Motorola PowerPC 602
3258 603 Motorola/IBM PowerPC 603 or 603e
3259 604 Motorola PowerPC 604 or 604e
3260 750 Motorola/IBM PowerPC 750 or 750
3262 At the moment, this command just tells GDB what to name the
3263 special-purpose processor registers. Since almost all the affected
3264 registers are inaccessible to user-level programs, this command is
3265 only useful for remote debugging in its present form.
3269 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3270 more extensive support for HP-UX. Added features include shared
3271 library support, kernel threads and hardware watchpoints for 11.00,
3272 support for HP's ANSI C and C++ compilers, and a compatibility mode
3273 for xdb and dbx commands.
3277 HP's donation includes the new concept of catchpoints, which is a
3278 generalization of the old catch command. On HP-UX, it is now possible
3279 to catch exec, fork, and vfork, as well as library loading.
3281 This means that the existing catch command has changed; its first
3282 argument now specifies the type of catch to be set up. See the
3283 output of "help catch" for a list of catchpoint types.
3285 * Debugging across forks
3287 On HP-UX, you can choose which process to debug when a fork() happens
3292 HP has donated a curses-based terminal user interface (TUI). To get
3293 it, build with --enable-tui. Although this can be enabled for any
3294 configuration, at present it only works for native HP debugging.
3296 * GDB remote protocol additions
3298 A new protocol packet 'X' that writes binary data is now available.
3299 Default behavior is to try 'X', then drop back to 'M' if the stub
3300 fails to respond. The settable variable `remotebinarydownload'
3301 allows explicit control over the use of 'X'.
3303 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3304 full 64-bit address. The command
3306 set remoteaddresssize 32
3308 can be used to revert to the old behaviour. For existing remote stubs
3309 the change should not be noticed, as the additional address information
3312 In order to assist in debugging stubs, you may use the maintenance
3313 command `packet' to send any text string to the stub. For instance,
3315 maint packet heythere
3317 sends the packet "$heythere#<checksum>". Note that it is very easy to
3318 disrupt a debugging session by sending the wrong packet at the wrong
3321 The compare-sections command allows you to compare section data on the
3322 target to what is in the executable file without uploading or
3323 downloading, by comparing CRC checksums.
3325 * Tracing can collect general expressions
3327 You may now collect general expressions at tracepoints. This requires
3328 further additions to the target-side stub; see tracepoint.c and
3329 doc/agentexpr.texi for further details.
3331 * mask-address variable for Mips
3333 For Mips targets, you may control the zeroing of the upper 32 bits of
3334 a 64-bit address by entering `set mask-address on'. This is mainly
3335 of interest to users of embedded R4xxx and R5xxx processors.
3337 * Higher serial baud rates
3339 GDB's serial code now allows you to specify baud rates 57600, 115200,
3340 230400, and 460800 baud. (Note that your host system may not be able
3341 to achieve all of these rates.)
3345 The i960 configuration now includes an initial implementation of a
3346 builtin simulator, contributed by Jim Wilson.
3349 *** Changes in GDB-4.17:
3351 * New native configurations
3353 Alpha GNU/Linux alpha*-*-linux*
3354 Unixware 2.x i[3456]86-unixware2*
3355 Irix 6.x mips*-sgi-irix6*
3356 PowerPC GNU/Linux powerpc-*-linux*
3357 PowerPC Solaris powerpcle-*-solaris*
3358 Sparc GNU/Linux sparc-*-linux*
3359 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3363 Argonaut Risc Chip (ARC) arc-*-*
3364 Hitachi H8/300S h8300*-*-*
3365 Matsushita MN10200 w/simulator mn10200-*-*
3366 Matsushita MN10300 w/simulator mn10300-*-*
3367 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3368 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3369 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3370 Mitsubishi D10V w/simulator d10v-*-*
3371 Mitsubishi M32R/D w/simulator m32r-*-elf*
3372 Tsqware Sparclet sparclet-*-*
3373 NEC V850 w/simulator v850-*-*
3375 * New debugging protocols
3377 ARM with RDI protocol arm*-*-*
3378 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3379 DDB and LSI variants of PMON protocol mips*-*-*
3380 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3381 PowerPC with SDS protocol powerpc{,le}-*-eabi
3382 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3386 All configurations can now understand and use the DWARF 2 debugging
3387 format. The choice is automatic, if the symbol file contains DWARF 2
3392 GDB now includes basic Java language support. This support is
3393 only useful with Java compilers that produce native machine code.
3395 * solib-absolute-prefix and solib-search-path
3397 For SunOS and SVR4 shared libraries, you may now set the prefix for
3398 loading absolute shared library symbol files, and the search path for
3399 locating non-absolute shared library symbol files.
3401 * Live range splitting
3403 GDB can now effectively debug code for which GCC has performed live
3404 range splitting as part of its optimization. See gdb/doc/LRS for
3405 more details on the expected format of the stabs information.
3409 GDB's support for the GNU Hurd, including thread debugging, has been
3410 updated to work with current versions of the Hurd.
3414 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3415 instruction set. ARM GDB automatically detects when Thumb
3416 instructions are in use, and adjusts disassembly and backtracing
3421 GDB's MIPS target configurations now handle the MIP16 16-bit
3426 GDB now includes support for overlays; if an executable has been
3427 linked such that multiple sections are based at the same address, GDB
3428 will decide which section to use for symbolic info. You can choose to
3429 control the decision manually, using overlay commands, or implement
3430 additional target-side support and use "overlay load-target" to bring
3431 in the overlay mapping. Do "help overlay" for more detail.
3435 The command "info symbol <address>" displays information about
3436 the symbol at the specified address.
3440 The standard remote protocol now includes an extension that allows
3441 asynchronous collection and display of trace data. This requires
3442 extensive support in the target-side debugging stub. Tracing mode
3443 includes a new interaction mode in GDB and new commands: see the
3444 file tracepoint.c for more details.
3448 Configurations for embedded MIPS now include a simulator contributed
3449 by Cygnus Solutions. The simulator supports the instruction sets
3450 of most MIPS variants.
3454 Sparc configurations may now include the ERC32 simulator contributed
3455 by the European Space Agency. The simulator is not built into
3456 Sparc targets by default; configure with --enable-sim to include it.
3460 For target configurations that may include multiple variants of a
3461 basic architecture (such as MIPS and SH), you may now set the
3462 architecture explicitly. "set arch" sets, "info arch" lists
3463 the possible architectures.
3465 *** Changes in GDB-4.16:
3467 * New native configurations
3469 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3470 M68K NetBSD m68k-*-netbsd*
3471 PowerPC AIX 4.x powerpc-*-aix*
3472 PowerPC MacOS powerpc-*-macos*
3473 PowerPC Windows NT powerpcle-*-cygwin32
3474 RS/6000 AIX 4.x rs6000-*-aix4*
3478 ARM with RDP protocol arm-*-*
3479 I960 with MON960 i960-*-coff
3480 MIPS VxWorks mips*-*-vxworks*
3481 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3482 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3484 Matra Sparclet sparclet-*-*
3488 The powerpc-eabi configuration now includes the PSIM simulator,
3489 contributed by Andrew Cagney, with assistance from Mike Meissner.
3490 PSIM is a very elaborate model of the PowerPC, including not only
3491 basic instruction set execution, but also details of execution unit
3492 performance and I/O hardware. See sim/ppc/README for more details.
3496 GDB now works with Solaris 2.5.
3498 * Windows 95/NT native
3500 GDB will now work as a native debugger on Windows 95 and Windows NT.
3501 To build it from source, you must use the "gnu-win32" environment,
3502 which uses a DLL to emulate enough of Unix to run the GNU tools.
3503 Further information, binaries, and sources are available at
3504 ftp.cygnus.com, under pub/gnu-win32.
3506 * dont-repeat command
3508 If a user-defined command includes the command `dont-repeat', then the
3509 command will not be repeated if the user just types return. This is
3510 useful if the command is time-consuming to run, so that accidental
3511 extra keystrokes don't run the same command many times.
3513 * Send break instead of ^C
3515 The standard remote protocol now includes an option to send a break
3516 rather than a ^C to the target in order to interrupt it. By default,
3517 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3519 * Remote protocol timeout
3521 The standard remote protocol includes a new variable `remotetimeout'
3522 that allows you to set the number of seconds before GDB gives up trying
3523 to read from the target. The default value is 2.
3525 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3527 By default GDB will automatically keep track of objects as they are
3528 loaded and unloaded by the dynamic linker. By using the command `set
3529 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3530 when shared library events occur, thus allowing you to set breakpoints
3531 in shared libraries which are explicitly loaded by the inferior.
3533 Note this feature does not work on hpux8. On hpux9 you must link
3534 /usr/lib/end.o into your program. This feature should work
3535 automatically on hpux10.
3537 * Irix 5.x hardware watchpoint support
3539 Irix 5 configurations now support the use of hardware watchpoints.
3541 * Mips protocol "SYN garbage limit"
3543 When debugging a Mips target using the `target mips' protocol, you
3544 may set the number of characters that GDB will ignore by setting
3545 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3546 every character. The default value is 1050.
3548 * Recording and replaying remote debug sessions
3550 If you set `remotelogfile' to the name of a file, gdb will write to it
3551 a recording of a remote debug session. This recording may then be
3552 replayed back to gdb using "gdbreplay". See gdbserver/README for
3553 details. This is useful when you have a problem with GDB while doing
3554 remote debugging; you can make a recording of the session and send it
3555 to someone else, who can then recreate the problem.
3557 * Speedups for remote debugging
3559 GDB includes speedups for downloading and stepping MIPS systems using
3560 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3561 and more efficient S-record downloading.
3563 * Memory use reductions and statistics collection
3565 GDB now uses less memory and reports statistics about memory usage.
3566 Try the `maint print statistics' command, for example.
3568 *** Changes in GDB-4.15:
3570 * Psymtabs for XCOFF
3572 The symbol reader for AIX GDB now uses partial symbol tables. This
3573 can greatly improve startup time, especially for large executables.
3575 * Remote targets use caching
3577 Remote targets now use a data cache to speed up communication with the
3578 remote side. The data cache could lead to incorrect results because
3579 it doesn't know about volatile variables, thus making it impossible to
3580 debug targets which use memory mapped I/O devices. `set remotecache
3581 off' turns the the data cache off.
3583 * Remote targets may have threads
3585 The standard remote protocol now includes support for multiple threads
3586 in the target system, using new protocol commands 'H' and 'T'. See
3587 gdb/remote.c for details.
3591 If GDB is configured with `--enable-netrom', then it will include
3592 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3593 acts as though it is a bank of ROM on the target board, but you can
3594 write into it over the network. GDB's support consists only of
3595 support for fast loading into the emulated ROM; to debug, you must use
3596 another protocol, such as standard remote protocol. The usual
3597 sequence is something like
3599 target nrom <netrom-hostname>
3601 target remote <netrom-hostname>:1235
3605 GDB now includes support for the Apple Macintosh, as a host only. It
3606 may be run as either an MPW tool or as a standalone application, and
3607 it can debug through the serial port. All the usual GDB commands are
3608 available, but to the target command, you must supply "serial" as the
3609 device type instead of "/dev/ttyXX". See mpw-README in the main
3610 directory for more information on how to build. The MPW configuration
3611 scripts */mpw-config.in support only a few targets, and only the
3612 mips-idt-ecoff target has been tested.
3616 GDB configuration now uses autoconf. This is not user-visible,
3617 but does simplify configuration and building.
3621 GDB now supports hpux10.
3623 *** Changes in GDB-4.14:
3625 * New native configurations
3627 x86 FreeBSD i[345]86-*-freebsd
3628 x86 NetBSD i[345]86-*-netbsd
3629 NS32k NetBSD ns32k-*-netbsd
3630 Sparc NetBSD sparc-*-netbsd
3634 A29K VxWorks a29k-*-vxworks
3635 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3636 CPU32 EST-300 emulator m68*-*-est*
3637 PowerPC ELF powerpc-*-elf
3640 * Alpha OSF/1 support for procfs
3642 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3643 possible to attach to running processes. As the mounting of the /proc
3644 filesystem is optional on the Alpha, GDB automatically determines
3645 the availability of /proc during startup. This can lead to problems
3646 if /proc is unmounted after GDB has been started.
3648 * Arguments to user-defined commands
3650 User commands may accept up to 10 arguments separated by whitespace.
3651 Arguments are accessed within the user command via $arg0..$arg9. A
3654 print $arg0 + $arg1 + $arg2
3656 To execute the command use:
3659 Defines the command "adder" which prints the sum of its three arguments.
3660 Note the arguments are text substitutions, so they may reference variables,
3661 use complex expressions, or even perform inferior function calls.
3663 * New `if' and `while' commands
3665 This makes it possible to write more sophisticated user-defined
3666 commands. Both commands take a single argument, which is the
3667 expression to evaluate, and must be followed by the commands to
3668 execute, one per line, if the expression is nonzero, the list being
3669 terminated by the word `end'. The `if' command list may include an
3670 `else' word, which causes the following commands to be executed only
3671 if the expression is zero.
3673 * Fortran source language mode
3675 GDB now includes partial support for Fortran 77. It will recognize
3676 Fortran programs and can evaluate a subset of Fortran expressions, but
3677 variables and functions may not be handled correctly. GDB will work
3678 with G77, but does not yet know much about symbols emitted by other
3681 * Better HPUX support
3683 Most debugging facilities now work on dynamic executables for HPPAs
3684 running hpux9 or later. You can attach to running dynamically linked
3685 processes, but by default the dynamic libraries will be read-only, so
3686 for instance you won't be able to put breakpoints in them. To change
3687 that behavior do the following before running the program:
3693 This will cause the libraries to be mapped private and read-write.
3694 To revert to the normal behavior, do this:
3700 You cannot set breakpoints or examine data in the library until after
3701 the library is loaded if the function/data symbols do not have
3704 GDB can now also read debug symbols produced by the HP C compiler on
3705 HPPAs (sorry, no C++, Fortran or 68k support).
3707 * Target byte order now dynamically selectable
3709 You can choose which byte order to use with a target system, via the
3710 commands "set endian big" and "set endian little", and you can see the
3711 current setting by using "show endian". You can also give the command
3712 "set endian auto", in which case GDB will use the byte order
3713 associated with the executable. Currently, only embedded MIPS
3714 configurations support dynamic selection of target byte order.
3716 * New DOS host serial code
3718 This version uses DPMI interrupts to handle buffered I/O, so you
3719 no longer need to run asynctsr when debugging boards connected to
3722 *** Changes in GDB-4.13:
3724 * New "complete" command
3726 This lists all the possible completions for the rest of the line, if it
3727 were to be given as a command itself. This is intended for use by emacs.
3729 * Trailing space optional in prompt
3731 "set prompt" no longer adds a space for you after the prompt you set. This
3732 allows you to set a prompt which ends in a space or one that does not.
3734 * Breakpoint hit counts
3736 "info break" now displays a count of the number of times the breakpoint
3737 has been hit. This is especially useful in conjunction with "ignore"; you
3738 can ignore a large number of breakpoint hits, look at the breakpoint info
3739 to see how many times the breakpoint was hit, then run again, ignoring one
3740 less than that number, and this will get you quickly to the last hit of
3743 * Ability to stop printing at NULL character
3745 "set print null-stop" will cause GDB to stop printing the characters of
3746 an array when the first NULL is encountered. This is useful when large
3747 arrays actually contain only short strings.
3749 * Shared library breakpoints
3751 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3752 breakpoints in shared libraries before the executable is run.
3754 * Hardware watchpoints
3756 There is a new hardware breakpoint for the watch command for sparclite
3757 targets. See gdb/sparclite/hw_breakpoint.note.
3759 Hardware watchpoints are also now supported under GNU/Linux.
3763 Annotations have been added. These are for use with graphical interfaces,
3764 and are still experimental. Currently only gdba.el uses these.
3766 * Improved Irix 5 support
3768 GDB now works properly with Irix 5.2.
3770 * Improved HPPA support
3772 GDB now works properly with the latest GCC and GAS.
3774 * New native configurations
3776 Sequent PTX4 i[34]86-sequent-ptx4
3777 HPPA running OSF/1 hppa*-*-osf*
3778 Atari TT running SVR4 m68*-*-sysv4*
3779 RS/6000 LynxOS rs6000-*-lynxos*
3783 OS/9000 i[34]86-*-os9k
3784 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3787 * Hitachi SH7000 and E7000-PC ICE support
3789 There is now support for communicating with the Hitachi E7000-PC ICE.
3790 This is available automatically when GDB is configured for the SH.
3794 As usual, a variety of small fixes and improvements, both generic
3795 and configuration-specific. See the ChangeLog for more detail.
3797 *** Changes in GDB-4.12:
3799 * Irix 5 is now supported
3803 GDB-4.12 on the HPPA has a number of changes which make it unable
3804 to debug the output from the currently released versions of GCC and
3805 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3806 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3807 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3810 *** Changes in GDB-4.11:
3812 * User visible changes:
3816 The "set remotedebug" option is now consistent between the mips remote
3817 target, remote targets using the gdb-specific protocol, UDI (AMD's
3818 debug protocol for the 29k) and the 88k bug monitor. It is now an
3819 integer specifying a debug level (normally 0 or 1, but 2 means more
3820 debugging info for the mips target).
3822 * DEC Alpha native support
3824 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3825 debug info, but GDB works fairly well with the DEC compiler and should
3826 work with a future GCC release. See the README file for a few
3827 Alpha-specific notes.
3829 * Preliminary thread implementation
3831 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3833 * LynxOS native and target support for 386
3835 This release has been hosted on LynxOS 2.2, and also can be configured
3836 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3839 * Improvements in C++ mangling/demangling.
3841 This release has much better g++ debugging, specifically in name
3842 mangling/demangling, virtual function calls, print virtual table,
3843 call methods, ...etc.
3845 *** Changes in GDB-4.10:
3847 * User visible changes:
3849 Remote debugging using the GDB-specific (`target remote') protocol now
3850 supports the `load' command. This is only useful if you have some
3851 other way of getting the stub to the target system, and you can put it
3852 somewhere in memory where it won't get clobbered by the download.
3854 Filename completion now works.
3856 When run under emacs mode, the "info line" command now causes the
3857 arrow to point to the line specified. Also, "info line" prints
3858 addresses in symbolic form (as well as hex).
3860 All vxworks based targets now support a user settable option, called
3861 vxworks-timeout. This option represents the number of seconds gdb
3862 should wait for responses to rpc's. You might want to use this if
3863 your vxworks target is, perhaps, a slow software simulator or happens
3864 to be on the far side of a thin network line.
3868 This release contains support for using a DEC alpha as a GDB host for
3869 cross debugging. Native alpha debugging is not supported yet.
3872 *** Changes in GDB-4.9:
3876 This is the first GDB release which is accompanied by a matching testsuite.
3877 The testsuite requires installation of dejagnu, which should be available
3878 via ftp from most sites that carry GNU software.
3882 'Cfront' style demangling has had its name changed to 'ARM' style, to
3883 emphasize that it was written from the specifications in the C++ Annotated
3884 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3885 disclaimers, it still generated too much confusion with users attempting to
3886 use gdb with AT&T cfront.
3890 GDB now uses a standard remote interface to a simulator library.
3891 So far, the library contains simulators for the Zilog Z8001/2, the
3892 Hitachi H8/300, H8/500 and Super-H.
3894 * New targets supported
3896 H8/300 simulator h8300-hitachi-hms or h8300hms
3897 H8/500 simulator h8500-hitachi-hms or h8500hms
3898 SH simulator sh-hitachi-hms or sh
3899 Z8000 simulator z8k-zilog-none or z8ksim
3900 IDT MIPS board over serial line mips-idt-ecoff
3902 Cross-debugging to GO32 targets is supported. It requires a custom
3903 version of the i386-stub.c module which is integrated with the
3904 GO32 memory extender.
3906 * New remote protocols
3908 MIPS remote debugging protocol.
3910 * New source languages supported
3912 This version includes preliminary support for Chill, a Pascal like language
3913 used by telecommunications companies. Chill support is also being integrated
3914 into the GNU compiler, but we don't know when it will be publically available.
3917 *** Changes in GDB-4.8:
3919 * HP Precision Architecture supported
3921 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3922 version of this support was available as a set of patches from the
3923 University of Utah. GDB does not support debugging of programs
3924 compiled with the HP compiler, because HP will not document their file
3925 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3926 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3928 Many problems in the preliminary version have been fixed.
3930 * Faster and better demangling
3932 We have improved template demangling and fixed numerous bugs in the GNU style
3933 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3934 character types (wchar_t) are now supported. Demangling of each symbol is now
3935 only done once, and is cached when the symbol table for a file is read in.
3936 This results in a small increase in memory usage for C programs, a moderate
3937 increase in memory usage for C++ programs, and a fantastic speedup in
3940 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3941 from the specifications in the Annotated Reference Manual, which AT&T's
3942 compiler does not actually implement.
3944 * G++ multiple inheritance compiler problem
3946 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3947 inheritance lattices was reworked to properly discover ambiguities. We
3948 recently found an example which causes this new algorithm to fail in a
3949 very subtle way, producing bad debug information for those classes.
3950 The file 'gcc.patch' (in this directory) can be applied to gcc to
3951 circumvent the problem. A future GCC release will contain a complete
3954 The previous G++ debug info problem (mentioned below for the gdb-4.7
3955 release) is fixed in gcc version 2.3.2.
3957 * Improved configure script
3959 The `configure' script will now attempt to guess your system type if
3960 you don't supply a host system type. The old scheme of supplying a
3961 host system triplet is preferable over using this. All the magic is
3962 done in the new `config.guess' script. Examine it for details.
3964 We have also brought our configure script much more in line with the FSF's
3965 version. It now supports the --with-xxx options. In particular,
3966 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3967 The resulting GDB will not be able to read arbitrary object file formats --
3968 only the format ``expected'' to be used on the configured target system.
3969 We hope to make this the default in a future release.
3971 * Documentation improvements
3973 There's new internal documentation on how to modify GDB, and how to
3974 produce clean changes to the code. We implore people to read it
3975 before submitting changes.
3977 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3978 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3979 `info' files are also provided. To build `info' files from scratch,
3980 you will need the latest `makeinfo' release, which will be available in
3981 a future texinfo-X.Y release.
3983 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3984 We're not sure exactly which versions have this problem, but it has
3985 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3986 or better. If that isn't possible, there is a patch in
3987 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3988 around this problem.
3992 GDB now supports array constants that can be used in expressions typed in by
3993 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3994 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3997 The new directory `gdb/sparclite' contains a program that demonstrates
3998 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4000 * New native hosts supported
4002 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4003 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4005 * New targets supported
4007 AMD 29k family via UDI a29k-amd-udi or udi29k
4009 * New file formats supported
4011 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4012 HPUX core files, and SCO 3.2v2 core files.
4016 Attaching to processes now works again; thanks for the many bug reports.
4018 We have also stomped on a bunch of core dumps caused by
4019 printf_filtered("%s") problems.
4021 We eliminated a copyright problem on the rpc and ptrace header files
4022 for VxWorks, which was discovered at the last minute during the 4.7
4023 release. You should now be able to build a VxWorks GDB.
4025 You can now interrupt gdb while an attached process is running. This
4026 will cause the attached process to stop, and give control back to GDB.
4028 We fixed problems caused by using too many file descriptors
4029 for reading symbols from object files and libraries. This was
4030 especially a problem for programs that used many (~100) shared
4033 The `step' command now only enters a subroutine if there is line number
4034 information for the subroutine. Otherwise it acts like the `next'
4035 command. Previously, `step' would enter subroutines if there was
4036 any debugging information about the routine. This avoids problems
4037 when using `cc -g1' on MIPS machines.
4039 * Internal improvements
4041 GDB's internal interfaces have been improved to make it easier to support
4042 debugging of multiple languages in the future.
4044 GDB now uses a common structure for symbol information internally.
4045 Minimal symbols (derived from linkage symbols in object files), partial
4046 symbols (from a quick scan of debug information), and full symbols
4047 contain a common subset of information, making it easier to write
4048 shared code that handles any of them.
4050 * New command line options
4052 We now accept --silent as an alias for --quiet.
4056 The memory-mapped-malloc library is now licensed under the GNU Library
4057 General Public License.
4059 *** Changes in GDB-4.7:
4061 * Host/native/target split
4063 GDB has had some major internal surgery to untangle the support for
4064 hosts and remote targets. Now, when you configure GDB for a remote
4065 target, it will no longer load in all of the support for debugging
4066 local programs on the host. When fully completed and tested, this will
4067 ensure that arbitrary host/target combinations are possible.
4069 The primary conceptual shift is to separate the non-portable code in
4070 GDB into three categories. Host specific code is required any time GDB
4071 is compiled on that host, regardless of the target. Target specific
4072 code relates to the peculiarities of the target, but can be compiled on
4073 any host. Native specific code is everything else: it can only be
4074 built when the host and target are the same system. Child process
4075 handling and core file support are two common `native' examples.
4077 GDB's use of /proc for controlling Unix child processes is now cleaner.
4078 It has been split out into a single module under the `target_ops' vector,
4079 plus two native-dependent functions for each system that uses /proc.
4081 * New hosts supported
4083 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4084 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4085 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4087 * New targets supported
4089 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4090 68030 and CPU32 m68030-*-*, m68332-*-*
4092 * New native hosts supported
4094 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4095 (386bsd is not well tested yet)
4096 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4098 * New file formats supported
4100 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4101 supports reading of `a.out.adobe' object files, which are an a.out
4102 format extended with minimal information about multiple sections.
4106 `show copying' is the same as the old `info copying'.
4107 `show warranty' is the same as `info warrantee'.
4108 These were renamed for consistency. The old commands continue to work.
4110 `info handle' is a new alias for `info signals'.
4112 You can now define pre-command hooks, which attach arbitrary command
4113 scripts to any command. The commands in the hook will be executed
4114 prior to the user's command. You can also create a hook which will be
4115 executed whenever the program stops. See gdb.texinfo.
4119 We now deal with Cfront style name mangling, and can even extract type
4120 info from mangled symbols. GDB can automatically figure out which
4121 symbol mangling style your C++ compiler uses.
4123 Calling of methods and virtual functions has been improved as well.
4127 The crash that occured when debugging Sun Ansi-C compiled binaries is
4128 fixed. This was due to mishandling of the extra N_SO stabs output
4131 We also finally got Ultrix 4.2 running in house, and fixed core file
4132 support, with help from a dozen people on the net.
4134 John M. Farrell discovered that the reason that single-stepping was so
4135 slow on all of the Mips based platforms (primarily SGI and DEC) was
4136 that we were trying to demangle and lookup a symbol used for internal
4137 purposes on every instruction that was being stepped through. Changing
4138 the name of that symbol so that it couldn't be mistaken for a C++
4139 mangled symbol sped things up a great deal.
4141 Rich Pixley sped up symbol lookups in general by getting much smarter
4142 about when C++ symbol mangling is necessary. This should make symbol
4143 completion (TAB on the command line) much faster. It's not as fast as
4144 we'd like, but it's significantly faster than gdb-4.6.
4148 A new user controllable variable 'call_scratch_address' can
4149 specify the location of a scratch area to be used when GDB
4150 calls a function in the target. This is necessary because the
4151 usual method of putting the scratch area on the stack does not work
4152 in systems that have separate instruction and data spaces.
4154 We integrated changes to support the 29k UDI (Universal Debugger
4155 Interface), but discovered at the last minute that we didn't have all
4156 of the appropriate copyright paperwork. We are working with AMD to
4157 resolve this, and hope to have it available soon.
4161 We have sped up the remote serial line protocol, especially for targets
4162 with lots of registers. It now supports a new `expedited status' ('T')
4163 message which can be used in place of the existing 'S' status message.
4164 This allows the remote stub to send only the registers that GDB
4165 needs to make a quick decision about single-stepping or conditional
4166 breakpoints, eliminating the need to fetch the entire register set for
4167 each instruction being stepped through.
4169 The GDB remote serial protocol now implements a write-through cache for
4170 registers, only re-reading the registers if the target has run.
4172 There is also a new remote serial stub for SPARC processors. You can
4173 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4174 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4175 processor with a serial port.
4179 Configure.in files have become much easier to read and modify. A new
4180 `table driven' format makes it more obvious what configurations are
4181 supported, and what files each one uses.
4185 There is a new opcodes library which will eventually contain all of the
4186 disassembly routines and opcode tables. At present, it only contains
4187 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4188 disassembler (binutils/objdump) to share these routines.
4190 The libiberty library is now copylefted under the GNU Library General
4191 Public License. This allows more liberal use, and was done so libg++
4192 can use it. This makes no difference to GDB, since the Library License
4193 grants all the rights from the General Public License.
4197 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4198 reference to the stabs symbol info used by the debugger. It is (as far
4199 as we know) the only published document on this fascinating topic. We
4200 encourage you to read it, compare it to the stabs information on your
4201 system, and send improvements on the document in general (to
4202 bug-gdb@prep.ai.mit.edu).
4204 And, of course, many bugs have been fixed.
4207 *** Changes in GDB-4.6:
4209 * Better support for C++ function names
4211 GDB now accepts as input the "demangled form" of C++ overloaded function
4212 names and member function names, and can do command completion on such names
4213 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4214 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4215 Make use of command completion, it is your friend.
4217 GDB also now accepts a variety of C++ mangled symbol formats. They are
4218 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4219 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4220 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4221 for the list of formats.
4223 * G++ symbol mangling problem
4225 Recent versions of gcc have a bug in how they emit debugging information for
4226 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4227 directory) can be applied to gcc to fix the problem. Alternatively, if you
4228 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4229 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4230 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4233 * New 'maintenance' command
4235 All of the commands related to hacking GDB internals have been moved out of
4236 the main command set, and now live behind the 'maintenance' command. This
4237 can also be abbreviated as 'mt'. The following changes were made:
4239 dump-me -> maintenance dump-me
4240 info all-breakpoints -> maintenance info breakpoints
4241 printmsyms -> maintenance print msyms
4242 printobjfiles -> maintenance print objfiles
4243 printpsyms -> maintenance print psymbols
4244 printsyms -> maintenance print symbols
4246 The following commands are new:
4248 maintenance demangle Call internal GDB demangler routine to
4249 demangle a C++ link name and prints the result.
4250 maintenance print type Print a type chain for a given symbol
4252 * Change to .gdbinit file processing
4254 We now read the $HOME/.gdbinit file before processing the argv arguments
4255 (e.g. reading symbol files or core files). This allows global parameters to
4256 be set, which will apply during the symbol reading. The ./.gdbinit is still
4257 read after argv processing.
4259 * New hosts supported
4261 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4263 GNU/Linux support i386-unknown-linux or linux
4265 We are also including code to support the HP/PA running BSD and HPUX. This
4266 is almost guaranteed not to work, as we didn't have time to test or build it
4267 for this release. We are including it so that the more adventurous (or
4268 masochistic) of you can play with it. We also had major problems with the
4269 fact that the compiler that we got from HP doesn't support the -g option.
4272 * New targets supported
4274 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4276 * More smarts about finding #include files
4278 GDB now remembers the compilation directory for all include files, and for
4279 all files from which C is generated (like yacc and lex sources). This
4280 greatly improves GDB's ability to find yacc/lex sources, and include files,
4281 especially if you are debugging your program from a directory different from
4282 the one that contains your sources.
4284 We also fixed a bug which caused difficulty with listing and setting
4285 breakpoints in include files which contain C code. (In the past, you had to
4286 try twice in order to list an include file that you hadn't looked at before.)
4288 * Interesting infernals change
4290 GDB now deals with arbitrary numbers of sections, where the symbols for each
4291 section must be relocated relative to that section's landing place in the
4292 target's address space. This work was needed to support ELF with embedded
4293 stabs used by Solaris-2.0.
4295 * Bug fixes (of course!)
4297 There have been loads of fixes for the following things:
4298 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4299 i960, stabs, DOS(GO32), procfs, etc...
4301 See the ChangeLog for details.
4303 *** Changes in GDB-4.5:
4305 * New machines supported (host and target)
4307 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4309 SGI Irix-4.x mips-sgi-irix4 or iris4
4311 * New malloc package
4313 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4314 Mmalloc is capable of handling mutiple heaps of memory. It is also
4315 capable of saving a heap to a file, and then mapping it back in later.
4316 This can be used to greatly speedup the startup of GDB by using a
4317 pre-parsed symbol table which lives in a mmalloc managed heap. For
4318 more details, please read mmalloc/mmalloc.texi.
4322 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4323 'help info proc' for details.
4325 * MIPS ecoff symbol table format
4327 The code that reads MIPS symbol table format is now supported on all hosts.
4328 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4331 * File name changes for MS-DOS
4333 Many files in the config directories have been renamed to make it easier to
4334 support GDB on MS-DOSe systems (which have very restrictive file name
4335 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4336 environment) is close to working but has some remaining problems. Note
4337 that debugging of DOS programs is not supported, due to limitations
4338 in the ``operating system'', but it can be used to host cross-debugging.
4340 * Cross byte order fixes
4342 Many fixes have been made to support cross debugging of Sparc and MIPS
4343 targets from hosts whose byte order differs.
4345 * New -mapped and -readnow options
4347 If memory-mapped files are available on your system through the 'mmap'
4348 system call, you can use the -mapped option on the `file' or
4349 `symbol-file' commands to cause GDB to write the symbols from your
4350 program into a reusable file. If the program you are debugging is
4351 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4352 Future GDB debugging sessions will notice the presence of this file,
4353 and will quickly map in symbol information from it, rather than reading
4354 the symbol table from the executable program. Using the '-mapped'
4355 option in a GDB `file' or `symbol-file' command has the same effect as
4356 starting GDB with the '-mapped' command-line option.
4358 You can cause GDB to read the entire symbol table immediately by using
4359 the '-readnow' option with any of the commands that load symbol table
4360 information (or on the GDB command line). This makes the command
4361 slower, but makes future operations faster.
4363 The -mapped and -readnow options are typically combined in order to
4364 build a `fred.syms' file that contains complete symbol information.
4365 A simple GDB invocation to do nothing but build a `.syms' file for future
4368 gdb -batch -nx -mapped -readnow programname
4370 The `.syms' file is specific to the host machine on which GDB is run.
4371 It holds an exact image of GDB's internal symbol table. It cannot be
4372 shared across multiple host platforms.
4374 * longjmp() handling
4376 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4377 siglongjmp() without losing control. This feature has not yet been ported to
4378 all systems. It currently works on many 386 platforms, all MIPS-based
4379 platforms (SGI, DECstation, etc), and Sun3/4.
4383 Preliminary work has been put in to support the new Solaris OS from Sun. At
4384 this time, it can control and debug processes, but it is not capable of
4389 As always, many many bug fixes. The major areas were with g++, and mipsread.
4390 People using the MIPS-based platforms should experience fewer mysterious
4391 crashes and trashed symbol tables.
4393 *** Changes in GDB-4.4:
4395 * New machines supported (host and target)
4397 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4399 BSD Reno on Vax vax-dec-bsd
4400 Ultrix on Vax vax-dec-ultrix
4402 * New machines supported (target)
4404 AMD 29000 embedded, using EBMON a29k-none-none
4408 GDB continues to improve its handling of C++. `References' work better.
4409 The demangler has also been improved, and now deals with symbols mangled as
4410 per the Annotated C++ Reference Guide.
4412 GDB also now handles `stabs' symbol information embedded in MIPS
4413 `ecoff' symbol tables. Since the ecoff format was not easily
4414 extensible to handle new languages such as C++, this appeared to be a
4415 good way to put C++ debugging info into MIPS binaries. This option
4416 will be supported in the GNU C compiler, version 2, when it is
4419 * New features for SVR4
4421 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4422 shared libraries. Debugging dynamically linked programs should present
4423 only minor differences from debugging statically linked programs.
4425 The `info proc' command will print out information about any process
4426 on an SVR4 system (including the one you are debugging). At the moment,
4427 it prints the address mappings of the process.
4429 If you bring up GDB on another SVR4 system, please send mail to
4430 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4432 * Better dynamic linking support in SunOS
4434 Reading symbols from shared libraries which contain debugging symbols
4435 now works properly. However, there remain issues such as automatic
4436 skipping of `transfer vector' code during function calls, which
4437 make it harder to debug code in a shared library, than to debug the
4438 same code linked statically.
4442 GDB is now using the latest `getopt' routines from the FSF. This
4443 version accepts the -- prefix for options with long names. GDB will
4444 continue to accept the old forms (-option and +option) as well.
4445 Various single letter abbreviations for options have been explicity
4446 added to the option table so that they won't get overshadowed in the
4447 future by other options that begin with the same letter.
4451 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4452 Many assorted bugs have been handled. Many more remain to be handled.
4453 See the various ChangeLog files (primarily in gdb and bfd) for details.
4456 *** Changes in GDB-4.3:
4458 * New machines supported (host and target)
4460 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4461 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4462 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4464 * Almost SCO Unix support
4466 We had hoped to support:
4467 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4468 (except for core file support), but we discovered very late in the release
4469 that it has problems with process groups that render gdb unusable. Sorry
4470 about that. I encourage people to fix it and post the fixes.
4472 * Preliminary ELF and DWARF support
4474 GDB can read ELF object files on System V Release 4, and can handle
4475 debugging records for C, in DWARF format, in ELF files. This support
4476 is preliminary. If you bring up GDB on another SVR4 system, please
4477 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4482 GDB now uses the latest `readline' library. One user-visible change
4483 is that two tabs will list possible command completions, which previously
4484 required typing M-? (meta-question mark, or ESC ?).
4488 The `stepi' bug that many of you noticed has been squashed.
4489 Many bugs in C++ have been handled. Many more remain to be handled.
4490 See the various ChangeLog files (primarily in gdb and bfd) for details.
4492 * State of the MIPS world (in case you wondered):
4494 GDB can understand the symbol tables emitted by the compilers
4495 supplied by most vendors of MIPS-based machines, including DEC. These
4496 symbol tables are in a format that essentially nobody else uses.
4498 Some versions of gcc come with an assembler post-processor called
4499 mips-tfile. This program is required if you want to do source-level
4500 debugging of gcc-compiled programs. I believe FSF does not ship
4501 mips-tfile with gcc version 1, but it will eventually come with gcc
4504 Debugging of g++ output remains a problem. g++ version 1.xx does not
4505 really support it at all. (If you're lucky, you should be able to get
4506 line numbers and stack traces to work, but no parameters or local
4507 variables.) With some work it should be possible to improve the
4510 When gcc version 2 is released, you will have somewhat better luck.
4511 However, even then you will get confusing results for inheritance and
4514 We will eventually provide full debugging of g++ output on
4515 DECstations. This will probably involve some kind of stabs-in-ecoff
4516 encapulation, but the details have not been worked out yet.
4519 *** Changes in GDB-4.2:
4521 * Improved configuration
4523 Only one copy of `configure' exists now, and it is not self-modifying.
4524 Porting BFD is simpler.
4528 The `step' and `next' commands now only stop at the first instruction
4529 of a source line. This prevents the multiple stops that used to occur
4530 in switch statements, for-loops, etc. `Step' continues to stop if a
4531 function that has debugging information is called within the line.
4535 Lots of small bugs fixed. More remain.
4537 * New host supported (not target)
4539 Intel 386 PC clone running Mach i386-none-mach
4542 *** Changes in GDB-4.1:
4544 * Multiple source language support
4546 GDB now has internal scaffolding to handle several source languages.
4547 It determines the type of each source file from its filename extension,
4548 and will switch expression parsing and number formatting to match the
4549 language of the function in the currently selected stack frame.
4550 You can also specifically set the language to be used, with
4551 `set language c' or `set language modula-2'.
4555 GDB now has preliminary support for the GNU Modula-2 compiler,
4556 currently under development at the State University of New York at
4557 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4558 continue through the fall of 1991 and into 1992.
4560 Other Modula-2 compilers are currently not supported, and attempting to
4561 debug programs compiled with them will likely result in an error as the
4562 symbol table is read. Feel free to work on it, though!
4564 There are hooks in GDB for strict type checking and range checking,
4565 in the `Modula-2 philosophy', but they do not currently work.
4569 GDB can now write to executable and core files (e.g. patch
4570 a variable's value). You must turn this switch on, specify
4571 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4572 by assigning a new value to a variable. Modifications take
4575 * Automatic SunOS shared library reading
4577 When you run your program, GDB automatically determines where its
4578 shared libraries (if any) have been loaded, and reads their symbols.
4579 The `share' command is no longer needed. This also works when
4580 examining core files.
4584 You can specify the number of lines that the `list' command shows.
4587 * New machines supported (host and target)
4589 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4590 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4591 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4593 * New hosts supported (not targets)
4595 IBM RT/PC: romp-ibm-aix or rtpc
4597 * New targets supported (not hosts)
4599 AMD 29000 embedded with COFF a29k-none-coff
4600 AMD 29000 embedded with a.out a29k-none-aout
4601 Ultracomputer remote kernel debug a29k-nyu-kern
4603 * New remote interfaces
4609 *** Changes in GDB-4.0:
4613 Wide output is wrapped at good places to make the output more readable.
4615 Gdb now supports cross-debugging from a host machine of one type to a
4616 target machine of another type. Communication with the target system
4617 is over serial lines. The ``target'' command handles connecting to the
4618 remote system; the ``load'' command will download a program into the
4619 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4620 also supports debugging of realtime processes running under VxWorks,
4621 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4622 stub on the target system.
4624 New CPUs supported include the AMD 29000 and Intel 960.
4626 GDB now reads object files and symbol tables via a ``binary file''
4627 library, which allows a single copy of GDB to debug programs of multiple
4628 object file types such as a.out and coff.
4630 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4631 refcard.dvi and refcard.ps are available to format it).
4634 * Control-Variable user interface simplified
4636 All variables that control the operation of the debugger can be set
4637 by the ``set'' command, and displayed by the ``show'' command.
4639 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4640 ``Show prompt'' produces the response:
4641 Gdb's prompt is new-gdb=>.
4643 What follows are the NEW set commands. The command ``help set'' will
4644 print a complete list of old and new set commands. ``help set FOO''
4645 will give a longer description of the variable FOO. ``show'' will show
4646 all of the variable descriptions and their current settings.
4648 confirm on/off: Enables warning questions for operations that are
4649 hard to recover from, e.g. rerunning the program while
4650 it is already running. Default is ON.
4652 editing on/off: Enables EMACS style command line editing
4653 of input. Previous lines can be recalled with
4654 control-P, the current line can be edited with control-B,
4655 you can search for commands with control-R, etc.
4658 history filename NAME: NAME is where the gdb command history
4659 will be stored. The default is .gdb_history,
4660 or the value of the environment variable
4663 history size N: The size, in commands, of the command history. The
4664 default is 256, or the value of the environment variable
4667 history save on/off: If this value is set to ON, the history file will
4668 be saved after exiting gdb. If set to OFF, the
4669 file will not be saved. The default is OFF.
4671 history expansion on/off: If this value is set to ON, then csh-like
4672 history expansion will be performed on
4673 command line input. The default is OFF.
4675 radix N: Sets the default radix for input and output. It can be set
4676 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4677 in the current radix, so "set radix 10" is always a no-op.
4679 height N: This integer value is the number of lines on a page. Default
4680 is 24, the current `stty rows'' setting, or the ``li#''
4681 setting from the termcap entry matching the environment
4684 width N: This integer value is the number of characters on a line.
4685 Default is 80, the current `stty cols'' setting, or the ``co#''
4686 setting from the termcap entry matching the environment
4689 Note: ``set screensize'' is obsolete. Use ``set height'' and
4690 ``set width'' instead.
4692 print address on/off: Print memory addresses in various command displays,
4693 such as stack traces and structure values. Gdb looks
4694 more ``symbolic'' if you turn this off; it looks more
4695 ``machine level'' with it on. Default is ON.
4697 print array on/off: Prettyprint arrays. New convenient format! Default
4700 print demangle on/off: Print C++ symbols in "source" form if on,
4703 print asm-demangle on/off: Same, for assembler level printouts
4706 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4709 * Support for Epoch Environment.
4711 The epoch environment is a version of Emacs v18 with windowing. One
4712 new command, ``inspect'', is identical to ``print'', except that if you
4713 are running in the epoch environment, the value is printed in its own
4717 * Support for Shared Libraries
4719 GDB can now debug programs and core files that use SunOS shared libraries.
4720 Symbols from a shared library cannot be referenced
4721 before the shared library has been linked with the program (this
4722 happens after you type ``run'' and before the function main() is entered).
4723 At any time after this linking (including when examining core files
4724 from dynamically linked programs), gdb reads the symbols from each
4725 shared library when you type the ``sharedlibrary'' command.
4726 It can be abbreviated ``share''.
4728 sharedlibrary REGEXP: Load shared object library symbols for files
4729 matching a unix regular expression. No argument
4730 indicates to load symbols for all shared libraries.
4732 info sharedlibrary: Status of loaded shared libraries.
4737 A watchpoint stops execution of a program whenever the value of an
4738 expression changes. Checking for this slows down execution
4739 tremendously whenever you are in the scope of the expression, but is
4740 quite useful for catching tough ``bit-spreader'' or pointer misuse
4741 problems. Some machines such as the 386 have hardware for doing this
4742 more quickly, and future versions of gdb will use this hardware.
4744 watch EXP: Set a watchpoint (breakpoint) for an expression.
4746 info watchpoints: Information about your watchpoints.
4748 delete N: Deletes watchpoint number N (same as breakpoints).
4749 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4750 enable N: Re-enables watchpoint number N (same as breakpoints).
4753 * C++ multiple inheritance
4755 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4758 * C++ exception handling
4760 Gdb now supports limited C++ exception handling. Besides the existing
4761 ability to breakpoint on an exception handler, gdb can breakpoint on
4762 the raising of an exception (before the stack is peeled back to the
4765 catch FOO: If there is a FOO exception handler in the dynamic scope,
4766 set a breakpoint to catch exceptions which may be raised there.
4767 Multiple exceptions (``catch foo bar baz'') may be caught.
4769 info catch: Lists all exceptions which may be caught in the
4770 current stack frame.
4773 * Minor command changes
4775 The command ``call func (arg, arg, ...)'' now acts like the print
4776 command, except it does not print or save a value if the function's result
4777 is void. This is similar to dbx usage.
4779 The ``up'' and ``down'' commands now always print the frame they end up
4780 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4781 frames without printing.
4783 * New directory command
4785 'dir' now adds directories to the FRONT of the source search path.
4786 The path starts off empty. Source files that contain debug information
4787 about the directory in which they were compiled can be found even
4788 with an empty path; Sun CC and GCC include this information. If GDB can't
4789 find your source file in the current directory, type "dir .".
4791 * Configuring GDB for compilation
4793 For normal use, type ``./configure host''. See README or gdb.texinfo
4796 GDB now handles cross debugging. If you are remotely debugging between
4797 two different machines, type ``./configure host -target=targ''.
4798 Host is the machine where GDB will run; targ is the machine
4799 where the program that you are debugging will run.