1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.4
8 ** The "maint set python print-stack on|off" is now deleted.
10 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
11 apply "flag enum"-style pretty-printing to any enum.
13 ** gdb.lookup_symbol can now work when there is no current frame.
15 ** gdb.Symbol now has a 'line' attribute, holding the line number in
16 the source at which the symbol was defined.
18 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
19 method 'value'. The former indicates whether the symbol needs a
20 frame in order to compute its value, and the latter computes the
23 * GDBserver now supports stdio connections.
24 E.g. (gdb) target remote | ssh myhost gdbserver - hello
26 * The binary "gdbtui" can no longer be built or installed.
27 Use "gdb -tui" instead.
29 * GDB will now print "flag" enums specially. A flag enum is one where
30 all the enumerator values have no bits in common when pairwise
31 "and"ed. When printing a value whose type is a flag enum, GDB will
32 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
33 (gdb) print (enum E) 3
36 * The filename part of a linespec will now match trailing components
37 of a source file name. For example, "break gcc/expr.c:1000" will
38 now set a breakpoint in build/gcc/expr.c, but not
41 * The "info proc" and "generate-core-file" commands will now also
42 work on remote targets connected to GDBserver on Linux.
44 * The command "info catch" has been removed. It has been disabled
49 ** "catch load" and "catch unload" can be used to stop when a shared
50 library is loaded or unloaded, respectively.
52 *** Changes in GDB 7.4
54 * GDB now handles ambiguous linespecs more consistently; the existing
55 FILE:LINE support has been expanded to other types of linespecs. A
56 breakpoint will now be set on all matching locations in all
57 inferiors, and locations will be added or removed according to
60 * GDB now allows you to skip uninteresting functions and files when
61 stepping with the "skip function" and "skip file" commands.
63 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
64 and "show remote hardware-watchpoint-length-limit". These allows to
65 set or show the maximum length limit (in bytes) of a remote
66 target hardware watchpoint.
68 This allows e.g. to use "unlimited" hardware watchpoints with the
69 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
70 watchpoints are slower than real hardware watchpoints but are
71 significantly faster than gdb software watchpoints.
75 ** The register_pretty_printer function in module gdb.printing now takes
76 an optional `replace' argument. If True, the new printer replaces any
79 ** The "maint set python print-stack on|off" command has been
80 deprecated and will be deleted in GDB 7.5.
81 A new command: "set python print-stack none|full|message" has
82 replaced it. Additionally, the default for "print-stack" is
83 now "message", which just prints the error message without
86 ** A prompt substitution hook (prompt_hook) is now available to the
89 ** A new Python module, gdb.prompt has been added to the GDB Python
90 modules library. This module provides functionality for
91 escape sequences in prompts (used by set/show
92 extended-prompt). These escape sequences are replaced by their
95 ** Python commands and convenience-functions located in
96 'data-directory'/python/gdb/command and
97 'data-directory'/python/gdb/function are now automatically loaded
100 ** Blocks now provide four new attributes. global_block and
101 static_block will return the global and static blocks
102 respectively. is_static and is_global are boolean attributes
103 that indicate if the block is one of those two types.
105 ** Symbols now provide the "type" attribute, the type of the symbol.
107 ** The "gdb.breakpoint" function has been deprecated in favor of
110 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
111 of a function. This class is based on the "finish" command
112 available in the CLI.
114 ** Type objects for struct and union types now allow access to
115 the fields using standard Python dictionary (mapping) methods.
116 For example, "some_type['myfield']" now works, as does
119 ** A new event "gdb.new_objfile" has been added, triggered by loading a
122 ** A new function, "deep_items" has been added to the gdb.types
123 module in the GDB Python modules library. This function returns
124 an iterator over the fields of a struct or union type. Unlike
125 the standard Python "iteritems" method, it will recursively traverse
126 any anonymous fields.
130 ** "*stopped" events can report several new "reason"s, such as
133 ** Breakpoint changes are now notified using new async records, like
134 "=breakpoint-modified".
136 ** New command -ada-task-info.
138 * libthread-db-search-path now supports two special values: $sdir and $pdir.
139 $sdir specifies the default system locations of shared libraries.
140 $pdir specifies the directory where the libpthread used by the application
143 GDB no longer looks in $sdir and $pdir after it has searched the directories
144 mentioned in libthread-db-search-path. If you want to search those
145 directories, they must be specified in libthread-db-search-path.
146 The default value of libthread-db-search-path on GNU/Linux and Solaris
147 systems is now "$sdir:$pdir".
149 $pdir is not supported by gdbserver, it is currently ignored.
150 $sdir is supported by gdbserver.
152 * New configure option --with-iconv-bin.
153 When using the internationalization support like the one in the GNU C
154 library, GDB will invoke the "iconv" program to get a list of supported
155 character sets. If this program lives in a non-standard location, one can
156 use this option to specify where to find it.
158 * When natively debugging programs on PowerPC BookE processors running
159 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
160 watchpoints, which specify a mask in addition to an address to watch.
161 The mask specifies that some bits of an address (the bits which are
162 reset in the mask) should be ignored when matching the address accessed
163 by the inferior against the watchpoint address. See the "PowerPC Embedded"
164 section in the user manual for more details.
166 * The new option --once causes GDBserver to stop listening for connections once
167 the first connection is made. The listening port used by GDBserver will
168 become available after that.
170 * New commands "info macros" and "alias" have been added.
172 * New function parameters suffix @entry specifies value of function parameter
173 at the time the function got called. Entry values are available only since
179 "!" is now an alias of the "shell" command.
180 Note that no space is needed between "!" and SHELL COMMAND.
184 watch EXPRESSION mask MASK_VALUE
185 The watch command now supports the mask argument which allows creation
186 of masked watchpoints, if the current architecture supports this feature.
188 info auto-load-scripts [REGEXP]
189 This command was formerly named "maintenance print section-scripts".
190 It is now generally useful and is no longer a maintenance-only command.
192 info macro [-all] [--] MACRO
193 The info macro command has new options `-all' and `--'. The first for
194 printing all definitions of a macro. The second for explicitly specifying
195 the end of arguments and the beginning of the macro name in case the macro
196 name starts with a hyphen.
198 collect[/s] EXPRESSIONS
199 The tracepoint collect command now takes an optional modifier "/s"
200 that directs it to dereference pointer-to-character types and
201 collect the bytes of memory up to a zero byte. The behavior is
202 similar to what you see when you use the regular print command on a
203 string. An optional integer following the "/s" sets a bound on the
204 number of bytes that will be collected.
207 The trace start command now interprets any supplied arguments as a
208 note to be recorded with the trace run, with an effect similar to
209 setting the variable trace-notes.
212 The trace stop command now interprets any arguments as a note to be
213 mentioned along with the tstatus report that the trace was stopped
214 with a command. The effect is similar to setting the variable
217 * Tracepoints can now be enabled and disabled at any time after a trace
218 experiment has been started using the standard "enable" and "disable"
219 commands. It is now possible to start a trace experiment with no enabled
220 tracepoints; GDB will display a warning, but will allow the experiment to
221 begin, assuming that tracepoints will be enabled as needed while the trace
224 * Fast tracepoints on 32-bit x86-architectures can now be placed at
225 locations with 4-byte instructions, when they were previously
226 limited to locations with instructions of 5 bytes or longer.
232 Set the GDB prompt, and allow escape sequences to be inserted to
233 display miscellaneous information (see 'help set extended-prompt'
234 for the list of sequences). This prompt (and any information
235 accessed through the escape sequences) is updated every time the
238 set print entry-values (both|compact|default|if-needed|no|only|preferred)
239 show print entry-values
240 Set printing of frame argument values at function entry. In some cases
241 GDB can determine the value of function argument which was passed by the
242 function caller, even if the value was modified inside the called function.
244 set debug entry-values
245 show debug entry-values
246 Control display of debugging info for determining frame argument values at
247 function entry and virtual tail call frames.
249 set basenames-may-differ
250 show basenames-may-differ
251 Set whether a source file may have multiple base names.
252 (A "base name" is the name of a file with the directory part removed.
253 Example: The base name of "/home/user/hello.c" is "hello.c".)
254 If set, GDB will canonicalize file names (e.g., expand symlinks)
255 before comparing them. Canonicalization is an expensive operation,
256 but it allows the same file be known by more than one base name.
257 If not set (the default), all source files are assumed to have just
258 one base name, and gdb will do file name comparisons more efficiently.
264 Set a user name and notes for the current and any future trace runs.
265 This is useful for long-running and/or disconnected traces, to
266 inform others (or yourself) as to who is running the trace, supply
267 contact information, or otherwise explain what is going on.
270 show trace-stop-notes
271 Set a note attached to the trace run, that is displayed when the
272 trace has been stopped by a tstop command. This is useful for
273 instance as an explanation, if you are stopping a trace run that was
274 started by someone else.
280 Dynamically enable a tracepoint in a started trace experiment.
284 Dynamically disable a tracepoint in a started trace experiment.
288 Set the user and notes of the trace run.
292 Query the current status of a tracepoint.
296 Query the minimum length of instruction at which a fast tracepoint may
299 * Dcache size (number of lines) and line-size are now runtime-configurable
300 via "set dcache line" and "set dcache line-size" commands.
304 Texas Instruments TMS320C6x tic6x-*-*
308 Renesas RL78 rl78-*-elf
310 *** Changes in GDB 7.3.1
312 * The build failure for NetBSD and OpenBSD targets have now been fixed.
314 *** Changes in GDB 7.3
316 * GDB has a new command: "thread find [REGEXP]".
317 It finds the thread id whose name, target id, or thread extra info
318 matches the given regular expression.
320 * The "catch syscall" command now works on mips*-linux* targets.
322 * The -data-disassemble MI command now supports modes 2 and 3 for
323 dumping the instruction opcodes.
325 * New command line options
327 -data-directory DIR Specify DIR as the "data-directory".
328 This is mostly for testing purposes.
330 * The "maint set python auto-load on|off" command has been renamed to
331 "set auto-load-scripts on|off".
333 * GDB has a new command: "set directories".
334 It is like the "dir" command except that it replaces the
335 source path list instead of augmenting it.
337 * GDB now understands thread names.
339 On GNU/Linux, "info threads" will display the thread name as set by
340 prctl or pthread_setname_np.
342 There is also a new command, "thread name", which can be used to
343 assign a name internally for GDB to display.
346 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
347 has been integrated into GDB.
351 ** The function gdb.Write now accepts an optional keyword 'stream'.
352 This keyword, when provided, will direct the output to either
353 stdout, stderr, or GDB's logging output.
355 ** Parameters can now be be sub-classed in Python, and in particular
356 you may implement the get_set_doc and get_show_doc functions.
357 This improves how Parameter set/show documentation is processed
358 and allows for more dynamic content.
360 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
361 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
362 have an is_valid method.
364 ** Breakpoints can now be sub-classed in Python, and in particular
365 you may implement a 'stop' function that is executed each time
366 the inferior reaches that breakpoint.
368 ** New function gdb.lookup_global_symbol looks up a global symbol.
370 ** GDB values in Python are now callable if the value represents a
371 function. For example, if 'some_value' represents a function that
372 takes two integer parameters and returns a value, you can call
373 that function like so:
375 result = some_value (10,20)
377 ** Module gdb.types has been added.
378 It contains a collection of utilities for working with gdb.Types objects:
379 get_basic_type, has_field, make_enum_dict.
381 ** Module gdb.printing has been added.
382 It contains utilities for writing and registering pretty-printers.
383 New classes: PrettyPrinter, SubPrettyPrinter,
384 RegexpCollectionPrettyPrinter.
385 New function: register_pretty_printer.
387 ** New commands "info pretty-printers", "enable pretty-printer" and
388 "disable pretty-printer" have been added.
390 ** gdb.parameter("directories") is now available.
392 ** New function gdb.newest_frame returns the newest frame in the
395 ** The gdb.InferiorThread class has a new "name" attribute. This
396 holds the thread's name.
398 ** Python Support for Inferior events.
399 Python scripts can add observers to be notified of events
400 occurring in the process being debugged.
401 The following events are currently supported:
402 - gdb.events.cont Continue event.
403 - gdb.events.exited Inferior exited event.
404 - gdb.events.stop Signal received, and Breakpoint hit events.
408 ** GDB now puts template parameters in scope when debugging in an
409 instantiation. For example, if you have:
411 template<int X> int func (void) { return X; }
413 then if you step into func<5>, "print X" will show "5". This
414 feature requires proper debuginfo support from the compiler; it
415 was added to GCC 4.5.
417 ** The motion commands "next", "finish", "until", and "advance" now
418 work better when exceptions are thrown. In particular, GDB will
419 no longer lose control of the inferior; instead, the GDB will
420 stop the inferior at the point at which the exception is caught.
421 This functionality requires a change in the exception handling
422 code that was introduced in GCC 4.5.
424 * GDB now follows GCC's rules on accessing volatile objects when
425 reading or writing target state during expression evaluation.
426 One notable difference to prior behavior is that "print x = 0"
427 no longer generates a read of x; the value of the assignment is
428 now always taken directly from the value being assigned.
430 * GDB now has some support for using labels in the program's source in
431 linespecs. For instance, you can use "advance label" to continue
432 execution to a label.
434 * GDB now has support for reading and writing a new .gdb_index
435 section. This section holds a fast index of DWARF debugging
436 information and can be used to greatly speed up GDB startup and
437 operation. See the documentation for `save gdb-index' for details.
439 * The "watch" command now accepts an optional "-location" argument.
440 When used, this causes GDB to watch the memory referred to by the
441 expression. Such a watchpoint is never deleted due to it going out
444 * GDB now supports thread debugging of core dumps on GNU/Linux.
446 GDB now activates thread debugging using the libthread_db library
447 when debugging GNU/Linux core dumps, similarly to when debugging
448 live processes. As a result, when debugging a core dump file, GDB
449 is now able to display pthread_t ids of threads. For example, "info
450 threads" shows the same output as when debugging the process when it
451 was live. In earlier releases, you'd see something like this:
454 * 1 LWP 6780 main () at main.c:10
456 While now you see this:
459 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
461 It is also now possible to inspect TLS variables when debugging core
464 When debugging a core dump generated on a machine other than the one
465 used to run GDB, you may need to point GDB at the correct
466 libthread_db library with the "set libthread-db-search-path"
467 command. See the user manual for more details on this command.
469 * When natively debugging programs on PowerPC BookE processors running
470 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
471 which stop execution of the inferior whenever it executes an instruction
472 at any address within the specified range. See the "PowerPC Embedded"
473 section in the user manual for more details.
475 * New features in the GDB remote stub, GDBserver
477 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
478 and i686 LynxOS (version 5.x).
480 ** GDBserver is now supported on Blackfin Linux.
482 * New native configurations
484 ia64 HP-UX ia64-*-hpux*
488 Analog Devices, Inc. Blackfin Processor bfin-*
490 * Ada task switching is now supported on sparc-elf targets when
491 debugging a program using the Ravenscar Profile. For more information,
492 see the "Tasking Support when using the Ravenscar Profile" section
493 in the GDB user manual.
495 * Guile support was removed.
497 * New features in the GNU simulator
499 ** The --map-info flag lists all known core mappings.
501 ** CFI flashes may be simulated via the "cfi" device.
503 *** Changes in GDB 7.2
505 * Shared library support for remote targets by default
507 When GDB is configured for a generic, non-OS specific target, like
508 for example, --target=arm-eabi or one of the many *-*-elf targets,
509 GDB now queries remote stubs for loaded shared libraries using the
510 `qXfer:libraries:read' packet. Previously, shared library support
511 was always disabled for such configurations.
515 ** Argument Dependent Lookup (ADL)
517 In C++ ADL lookup directs function search to the namespaces of its
518 arguments even if the namespace has not been imported.
528 Here the compiler will search for `foo' in the namespace of 'b'
529 and find A::foo. GDB now supports this. This construct is commonly
530 used in the Standard Template Library for operators.
532 ** Improved User Defined Operator Support
534 In addition to member operators, GDB now supports lookup of operators
535 defined in a namespace and imported with a `using' directive, operators
536 defined in the global scope, operators imported implicitly from an
537 anonymous namespace, and the ADL operators mentioned in the previous
539 GDB now also supports proper overload resolution for all the previously
540 mentioned flavors of operators.
542 ** static const class members
544 Printing of static const class members that are initialized in the
545 class definition has been fixed.
547 * Windows Thread Information Block access.
549 On Windows targets, GDB now supports displaying the Windows Thread
550 Information Block (TIB) structure. This structure is visible either
551 by using the new command `info w32 thread-information-block' or, by
552 dereferencing the new convenience variable named `$_tlb', a
553 thread-specific pointer to the TIB. This feature is also supported
554 when remote debugging using GDBserver.
558 Static tracepoints are calls in the user program into a tracing
559 library. One such library is a port of the LTTng kernel tracer to
560 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
561 When debugging with GDBserver, GDB now supports combining the GDB
562 tracepoint machinery with such libraries. For example: the user can
563 use GDB to probe a static tracepoint marker (a call from the user
564 program into the tracing library) with the new "strace" command (see
565 "New commands" below). This creates a "static tracepoint" in the
566 breakpoint list, that can be manipulated with the same feature set
567 as fast and regular tracepoints. E.g., collect registers, local and
568 global variables, collect trace state variables, and define
569 tracepoint conditions. In addition, the user can collect extra
570 static tracepoint marker specific data, by collecting the new
571 $_sdata internal variable. When analyzing the trace buffer, you can
572 inspect $_sdata like any other variable available to GDB. For more
573 information, see the "Tracepoints" chapter in GDB user manual. New
574 remote packets have been defined to support static tracepoints, see
575 the "New remote packets" section below.
577 * Better reconstruction of tracepoints after disconnected tracing
579 GDB will attempt to download the original source form of tracepoint
580 definitions when starting a trace run, and then will upload these
581 upon reconnection to the target, resulting in a more accurate
582 reconstruction of the tracepoints that are in use on the target.
586 You can now exercise direct control over the ways that GDB can
587 affect your program. For instance, you can disallow the setting of
588 breakpoints, so that the program can run continuously (assuming
589 non-stop mode). In addition, the "observer" variable is available
590 to switch all of the different controls; in observer mode, GDB
591 cannot affect the target's behavior at all, which is useful for
592 tasks like diagnosing live systems in the field.
594 * The new convenience variable $_thread holds the number of the
601 Return the address of the Windows Thread Information Block of a given thread.
605 In response to several of the tracepoint packets, the target may now
606 also respond with a number of intermediate `qRelocInsn' request
607 packets before the final result packet, to have GDB handle
608 relocating an instruction to execute at a different address. This
609 is particularly useful for stubs that support fast tracepoints. GDB
610 reports support for this feature in the qSupported packet.
614 List static tracepoint markers in the target program.
618 List static tracepoint markers at a given address in the target
621 qXfer:statictrace:read
623 Read the static trace data collected (by a `collect $_sdata'
624 tracepoint action). The remote stub reports support for this packet
625 to gdb's qSupported query.
629 Send the current settings of GDB's permission flags.
633 Send part of the source (textual) form of a tracepoint definition,
634 which includes location, conditional, and action list.
636 * The source command now accepts a -s option to force searching for the
637 script in the source search path even if the script name specifies
640 * New features in the GDB remote stub, GDBserver
642 - GDBserver now support tracepoints (including fast tracepoints, and
643 static tracepoints). The feature is currently supported by the
644 i386-linux and amd64-linux builds. See the "Tracepoints support
645 in gdbserver" section in the manual for more information.
647 GDBserver JIT compiles the tracepoint's conditional agent
648 expression bytecode into native code whenever possible for low
649 overhead dynamic tracepoints conditionals. For such tracepoints,
650 an expression that examines program state is evaluated when the
651 tracepoint is reached, in order to determine whether to capture
652 trace data. If the condition is simple and false, processing the
653 tracepoint finishes very quickly and no data is gathered.
655 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
656 for static tracepoints support.
658 - GDBserver now supports x86_64 Windows 64-bit debugging.
660 * GDB now sends xmlRegisters= in qSupported packet to indicate that
661 it understands register description.
663 * The --batch flag now disables pagination and queries.
665 * X86 general purpose registers
667 GDB now supports reading/writing byte, word and double-word x86
668 general purpose registers directly. This means you can use, say,
669 $ah or $ax to refer, respectively, to the byte register AH and
670 16-bit word register AX that are actually portions of the 32-bit
671 register EAX or 64-bit register RAX.
673 * The `commands' command now accepts a range of breakpoints to modify.
674 A plain `commands' following a command that creates multiple
675 breakpoints affects all the breakpoints set by that command. This
676 applies to breakpoints set by `rbreak', and also applies when a
677 single `break' command creates multiple breakpoints (e.g.,
678 breakpoints on overloaded c++ functions).
680 * The `rbreak' command now accepts a filename specification as part of
681 its argument, limiting the functions selected by the regex to those
682 in the specified file.
684 * Support for remote debugging Windows and SymbianOS shared libraries
685 from Unix hosts has been improved. Non Windows GDB builds now can
686 understand target reported file names that follow MS-DOS based file
687 system semantics, such as file names that include drive letters and
688 use the backslash character as directory separator. This makes it
689 possible to transparently use the "set sysroot" and "set
690 solib-search-path" on Unix hosts to point as host copies of the
691 target's shared libraries. See the new command "set
692 target-file-system-kind" described below, and the "Commands to
693 specify files" section in the user manual for more information.
697 eval template, expressions...
698 Convert the values of one or more expressions under the control
699 of the string template to a command line, and call it.
701 set target-file-system-kind unix|dos-based|auto
702 show target-file-system-kind
703 Set or show the assumed file system kind for target reported file
706 save breakpoints <filename>
707 Save all current breakpoint definitions to a file suitable for use
708 in a later debugging session. To read the saved breakpoint
709 definitions, use the `source' command.
711 `save tracepoints' is a new alias for `save-tracepoints'. The latter
714 info static-tracepoint-markers
715 Display information about static tracepoint markers in the target.
717 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
718 Define a static tracepoint by probing a marker at the given
719 function, line, address, or marker ID.
723 Enable and disable observer mode.
725 set may-write-registers on|off
726 set may-write-memory on|off
727 set may-insert-breakpoints on|off
728 set may-insert-tracepoints on|off
729 set may-insert-fast-tracepoints on|off
730 set may-interrupt on|off
731 Set individual permissions for GDB effects on the target. Note that
732 some of these settings can have undesirable or surprising
733 consequences, particularly when changed in the middle of a session.
734 For instance, disabling the writing of memory can prevent
735 breakpoints from being inserted, cause single-stepping to fail, or
736 even crash your program, if you disable after breakpoints have been
737 inserted. However, GDB should not crash.
739 set record memory-query on|off
740 show record memory-query
741 Control whether to stop the inferior if memory changes caused
742 by an instruction cannot be recorded.
747 The disassemble command now supports "start,+length" form of two arguments.
751 ** GDB now provides a new directory location, called the python directory,
752 where Python scripts written for GDB can be installed. The location
753 of that directory is <data-directory>/python, where <data-directory>
754 is the GDB data directory. For more details, see section `Scripting
755 GDB using Python' in the manual.
757 ** The GDB Python API now has access to breakpoints, symbols, symbol
758 tables, program spaces, inferiors, threads and frame's code blocks.
759 Additionally, GDB Parameters can now be created from the API, and
760 manipulated via set/show in the CLI.
762 ** New functions gdb.target_charset, gdb.target_wide_charset,
763 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
765 ** New exception gdb.GdbError.
767 ** Pretty-printers are now also looked up in the current program space.
769 ** Pretty-printers can now be individually enabled and disabled.
771 ** GDB now looks for names of Python scripts to auto-load in a
772 special section named `.debug_gdb_scripts', in addition to looking
773 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
775 * Tracepoint actions were unified with breakpoint commands. In particular,
776 there are no longer differences in "info break" output for breakpoints and
777 tracepoints and the "commands" command can be used for both tracepoints and
782 ARM Symbian arm*-*-symbianelf*
784 * D language support.
785 GDB now supports debugging programs written in the D programming
788 * GDB now supports the extended ptrace interface for PowerPC which is
789 available since Linux kernel version 2.6.34. This automatically enables
790 any hardware breakpoints and additional hardware watchpoints available in
791 the processor. The old ptrace interface exposes just one hardware
792 watchpoint and no hardware breakpoints.
794 * GDB is now able to use the Data Value Compare (DVC) register available on
795 embedded PowerPC processors to implement in hardware simple watchpoint
796 conditions of the form:
798 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
800 This works in native GDB running on Linux kernels with the extended ptrace
801 interface mentioned above.
803 *** Changes in GDB 7.1
809 GDB now supports importing of namespaces in C++. This enables the
810 user to inspect variables from imported namespaces. Support for
811 namepace aliasing has also been added. So, if a namespace is
812 aliased in the current scope (e.g. namepace C=A; ) the user can
813 print variables using the alias (e.g. (gdb) print C::x).
817 All known bugs relating to the printing of virtual base class were
818 fixed. It is now possible to call overloaded static methods using a
823 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
824 and reinterpret_cast<> are now handled by the C++ expression parser.
828 Xilinx MicroBlaze microblaze-*-*
833 Xilinx MicroBlaze microblaze
836 * Multi-program debugging.
838 GDB now has support for multi-program (a.k.a. multi-executable or
839 multi-exec) debugging. This allows for debugging multiple inferiors
840 simultaneously each running a different program under the same GDB
841 session. See "Debugging Multiple Inferiors and Programs" in the
842 manual for more information. This implied some user visible changes
843 in the multi-inferior support. For example, "info inferiors" now
844 lists inferiors that are not running yet or that have exited
845 already. See also "New commands" and "New options" below.
847 * New tracing features
849 GDB's tracepoint facility now includes several new features:
851 ** Trace state variables
853 GDB tracepoints now include support for trace state variables, which
854 are variables managed by the target agent during a tracing
855 experiment. They are useful for tracepoints that trigger each
856 other, so for instance one tracepoint can count hits in a variable,
857 and then a second tracepoint has a condition that is true when the
858 count reaches a particular value. Trace state variables share the
859 $-syntax of GDB convenience variables, and can appear in both
860 tracepoint actions and condition expressions. Use the "tvariable"
861 command to create, and "info tvariables" to view; see "Trace State
862 Variables" in the manual for more detail.
866 GDB now includes an option for defining fast tracepoints, which
867 targets may implement more efficiently, such as by installing a jump
868 into the target agent rather than a trap instruction. The resulting
869 speedup can be by two orders of magnitude or more, although the
870 tradeoff is that some program locations on some target architectures
871 might not allow fast tracepoint installation, for instance if the
872 instruction to be replaced is shorter than the jump. To request a
873 fast tracepoint, use the "ftrace" command, with syntax identical to
874 the regular trace command.
876 ** Disconnected tracing
878 It is now possible to detach GDB from the target while it is running
879 a trace experiment, then reconnect later to see how the experiment
880 is going. In addition, a new variable disconnected-tracing lets you
881 tell the target agent whether to continue running a trace if the
882 connection is lost unexpectedly.
886 GDB now has the ability to save the trace buffer into a file, and
887 then use that file as a target, similarly to you can do with
888 corefiles. You can select trace frames, print data that was
889 collected in them, and use tstatus to display the state of the
890 tracing run at the moment that it was saved. To create a trace
891 file, use "tsave <filename>", and to use it, do "target tfile
894 ** Circular trace buffer
896 You can ask the target agent to handle the trace buffer as a
897 circular buffer, discarding the oldest trace frames to make room for
898 newer ones, by setting circular-trace-buffer to on. This feature may
899 not be available for all target agents.
904 The disassemble command, when invoked with two arguments, now requires
905 the arguments to be comma-separated.
908 The info variables command now displays variable definitions. Files
909 which only declare a variable are not shown.
912 The source command is now capable of sourcing Python scripts.
913 This feature is dependent on the debugger being build with Python
916 Related to this enhancement is also the introduction of a new command
917 "set script-extension" (see below).
919 * New commands (for set/show, see "New options" below)
921 record save [<FILENAME>]
922 Save a file (in core file format) containing the process record
923 execution log for replay debugging at a later time.
925 record restore <FILENAME>
926 Restore the process record execution log that was saved at an
927 earlier time, for replay debugging.
929 add-inferior [-copies <N>] [-exec <FILENAME>]
932 clone-inferior [-copies <N>] [ID]
933 Make a new inferior ready to execute the same program another
939 maint info program-spaces
940 List the program spaces loaded into GDB.
942 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
943 show remote interrupt-sequence
944 Allow the user to select one of ^C, a BREAK signal or BREAK-g
945 as the sequence to the remote target in order to interrupt the execution.
946 Ctrl-C is a default. Some system prefers BREAK which is high level of
947 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
948 Magic SysRq g. It is BREAK signal and character 'g'.
950 set remote interrupt-on-connect [on | off]
951 show remote interrupt-on-connect
952 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
953 remote target when gdb connects to it. This is needed when you debug
956 set remotebreak [on | off]
958 Deprecated. Use "set/show remote interrupt-sequence" instead.
960 tvariable $NAME [ = EXP ]
961 Create or modify a trace state variable.
964 List trace state variables and their values.
966 delete tvariable $NAME ...
967 Delete one or more trace state variables.
970 Evaluate the given expressions without collecting anything into the
971 trace buffer. (Valid in tracepoint actions only.)
973 ftrace FN / FILE:LINE / *ADDR
974 Define a fast tracepoint at the given function, line, or address.
976 * New expression syntax
978 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
979 GDB now parses 0b101010 identically with 42.
983 set follow-exec-mode new|same
984 show follow-exec-mode
985 Control whether GDB reuses the same inferior across an exec call or
986 creates a new one. This is useful to be able to restart the old
987 executable after the inferior having done an exec call.
989 set default-collect EXPR, ...
991 Define a list of expressions to be collected at each tracepoint.
992 This is a useful way to ensure essential items are not overlooked,
993 such as registers or a critical global variable.
995 set disconnected-tracing
996 show disconnected-tracing
997 If set to 1, the target is instructed to continue tracing if it
998 loses its connection to GDB. If 0, the target is to stop tracing
1001 set circular-trace-buffer
1002 show circular-trace-buffer
1003 If set to on, the target is instructed to use a circular trace buffer
1004 and discard the oldest trace frames instead of stopping the trace due
1005 to a full trace buffer. If set to off, the trace stops when the buffer
1006 fills up. Some targets may not support this.
1008 set script-extension off|soft|strict
1009 show script-extension
1010 If set to "off", the debugger does not perform any script language
1011 recognition, and all sourced files are assumed to be GDB scripts.
1012 If set to "soft" (the default), files are sourced according to
1013 filename extension, falling back to GDB scripts if the first
1015 If set to "strict", files are sourced according to filename extension.
1017 set ada trust-PAD-over-XVS on|off
1018 show ada trust-PAD-over-XVS
1019 If off, activate a workaround against a bug in the debugging information
1020 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1021 the GCC sources for more information about the GNAT encoding and
1022 PAD types in particular). It is always safe to set this option to
1023 off, but this introduces a slight performance penalty. The default
1026 * Python API Improvements
1028 ** GDB provides the new class gdb.LazyString. This is useful in
1029 some pretty-printing cases. The new method gdb.Value.lazy_string
1030 provides a simple way to create objects of this type.
1032 ** The fields returned by gdb.Type.fields now have an
1033 `is_base_class' attribute.
1035 ** The new method gdb.Type.range returns the range of an array type.
1037 ** The new method gdb.parse_and_eval can be used to parse and
1038 evaluate an expression.
1040 * New remote packets
1043 Define a trace state variable.
1046 Get the current value of a trace state variable.
1049 Set desired tracing behavior upon disconnection.
1052 Set the trace buffer to be linear or circular.
1055 Get data about the tracepoints currently in use.
1059 Process record now works correctly with hardware watchpoints.
1061 Multiple bug fixes have been made to the mips-irix port, making it
1062 much more reliable. In particular:
1063 - Debugging threaded applications is now possible again. Previously,
1064 GDB would hang while starting the program, or while waiting for
1065 the program to stop at a breakpoint.
1066 - Attaching to a running process no longer hangs.
1067 - An error occurring while loading a core file has been fixed.
1068 - Changing the value of the PC register now works again. This fixes
1069 problems observed when using the "jump" command, or when calling
1070 a function from GDB, or even when assigning a new value to $pc.
1071 - With the "finish" and "return" commands, the return value for functions
1072 returning a small array is now correctly printed.
1073 - It is now possible to break on shared library code which gets executed
1074 during a shared library init phase (code executed while executing
1075 their .init section). Previously, the breakpoint would have no effect.
1076 - GDB is now able to backtrace through the signal handler for
1077 non-threaded programs.
1079 PIE (Position Independent Executable) programs debugging is now supported.
1080 This includes debugging execution of PIC (Position Independent Code) shared
1081 libraries although for that, it should be possible to run such libraries as an
1084 *** Changes in GDB 7.0
1086 * GDB now has an interface for JIT compilation. Applications that
1087 dynamically generate code can create symbol files in memory and register
1088 them with GDB. For users, the feature should work transparently, and
1089 for JIT developers, the interface is documented in the GDB manual in the
1090 "JIT Compilation Interface" chapter.
1092 * Tracepoints may now be conditional. The syntax is as for
1093 breakpoints; either an "if" clause appended to the "trace" command,
1094 or the "condition" command is available. GDB sends the condition to
1095 the target for evaluation using the same bytecode format as is used
1096 for tracepoint actions.
1098 * The disassemble command now supports: an optional /r modifier, print the
1099 raw instructions in hex as well as in symbolic form, and an optional /m
1100 modifier to print mixed source+assembly.
1102 * Process record and replay
1104 In a architecture environment that supports ``process record and
1105 replay'', ``process record and replay'' target can record a log of
1106 the process execution, and replay it with both forward and reverse
1109 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1110 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1111 set execution-direction {forward|reverse}, for targets that support
1114 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1115 feature is available with a native GDB running on kernel version
1118 * GDB now has support for multi-byte and wide character sets on the
1119 target. Strings whose character type is wchar_t, char16_t, or
1120 char32_t are now correctly printed. GDB supports wide- and unicode-
1121 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1122 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1123 `printf'. This feature requires iconv to work properly; if your
1124 system does not have a working iconv, GDB can use GNU libiconv. See
1125 the installation instructions for more information.
1127 * GDB now supports automatic retrieval of shared library files from
1128 remote targets. To use this feature, specify a system root that begins
1129 with the `remote:' prefix, either via the `set sysroot' command or via
1130 the `--with-sysroot' configure-time option.
1132 * "info sharedlibrary" now takes an optional regex of libraries to show,
1133 and it now reports if a shared library has no debugging information.
1135 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1136 now complete on file names.
1138 * When completing in expressions, gdb will attempt to limit
1139 completions to allowable structure or union fields, where appropriate.
1140 For instance, consider:
1142 # struct example { int f1; double f2; };
1143 # struct example variable;
1146 If the user types TAB at the end of this command line, the available
1147 completions will be "f1" and "f2".
1149 * Inlined functions are now supported. They show up in backtraces, and
1150 the "step", "next", and "finish" commands handle them automatically.
1152 * GDB now supports the token-splicing (##) and stringification (#)
1153 operators when expanding macros. It also supports variable-arity
1156 * GDB now supports inspecting extra signal information, exported by
1157 the new $_siginfo convenience variable. The feature is currently
1158 implemented on linux ARM, i386 and amd64.
1160 * GDB can now display the VFP floating point registers and NEON vector
1161 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1162 can provide these registers (requires Linux 2.6.30 or later). Remote
1163 and simulator targets may also provide them.
1165 * New remote packets
1168 Search memory for a sequence of bytes.
1171 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1172 operation over reliable transport links. Use of this packet is
1173 controlled by the `set remote noack-packet' command.
1176 Kill the process with the specified process ID. Use this in preference
1177 to `k' when multiprocess protocol extensions are supported.
1180 Obtains additional operating system information
1184 Read or write additional signal information.
1186 * Removed remote protocol undocumented extension
1188 An undocumented extension to the remote protocol's `S' stop reply
1189 packet that permited the stub to pass a process id was removed.
1190 Remote servers should use the `T' stop reply packet instead.
1192 * GDB now supports multiple function calling conventions according to the
1193 DWARF-2 DW_AT_calling_convention function attribute.
1195 * The SH target utilizes the aforementioned change to distinguish between gcc
1196 and Renesas calling convention. It also adds the new CLI commands
1197 `set/show sh calling-convention'.
1199 * GDB can now read compressed debug sections, as produced by GNU gold
1200 with the --compress-debug-sections=zlib flag.
1202 * 64-bit core files are now supported on AIX.
1204 * Thread switching is now supported on Tru64.
1206 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1207 which will be allocated using malloc later in program execution.
1209 * The qXfer:libraries:read remote procotol packet now allows passing a
1210 list of section offsets.
1212 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1213 conditions handling signals delivered during attach or thread creation
1214 have also been fixed.
1216 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1217 From the user's standpoint, all unqualified instances of True and False
1218 are treated as the standard definitions, regardless of context.
1220 * GDB now parses C++ symbol and type names more flexibly. For
1223 template<typename T> class C { };
1226 GDB will now correctly handle all of:
1228 ptype C<char const *>
1229 ptype C<char const*>
1230 ptype C<const char *>
1231 ptype C<const char*>
1233 * New features in the GDB remote stub, gdbserver
1235 - The "--wrapper" command-line argument tells gdbserver to use a
1236 wrapper program to launch programs for debugging.
1238 - On PowerPC and S/390 targets, it is now possible to use a single
1239 gdbserver executable to debug both 32-bit and 64-bit programs.
1240 (This requires gdbserver itself to be built as a 64-bit executable.)
1242 - gdbserver uses the new noack protocol mode for TCP connections to
1243 reduce communications latency, if also supported and enabled in GDB.
1245 - Support for the sparc64-linux-gnu target is now included in
1248 - The amd64-linux build of gdbserver now supports debugging both
1249 32-bit and 64-bit programs.
1251 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1252 now support hardware watchpoints, and will use them automatically
1257 GDB now has support for scripting using Python. Whether this is
1258 available is determined at configure time.
1260 New GDB commands can now be written in Python.
1262 * Ada tasking support
1264 Ada tasks can now be inspected in GDB. The following commands have
1268 Print the list of Ada tasks.
1270 Print detailed information about task number N.
1272 Print the task number of the current task.
1274 Switch the context of debugging to task number N.
1276 * Support for user-defined prefixed commands. The "define" command can
1277 add new commands to existing prefixes, e.g. "target".
1279 * Multi-inferior, multi-process debugging.
1281 GDB now has generalized support for multi-inferior debugging. See
1282 "Debugging Multiple Inferiors" in the manual for more information.
1283 Although availability still depends on target support, the command
1284 set is more uniform now. The GNU/Linux specific multi-forks support
1285 has been migrated to this new framework. This implied some user
1286 visible changes; see "New commands" and also "Removed commands"
1289 * Target descriptions can now describe the target OS ABI. See the
1290 "Target Description Format" section in the user manual for more
1293 * Target descriptions can now describe "compatible" architectures
1294 to indicate that the target can execute applications for a different
1295 architecture in addition to those for the main target architecture.
1296 See the "Target Description Format" section in the user manual for
1299 * Multi-architecture debugging.
1301 GDB now includes general supports for debugging applications on
1302 hybrid systems that use more than one single processor architecture
1303 at the same time. Each such hybrid architecture still requires
1304 specific support to be added. The only hybrid architecture supported
1305 in this version of GDB is the Cell Broadband Engine.
1307 * GDB now supports integrated debugging of Cell/B.E. applications that
1308 use both the PPU and SPU architectures. To enable support for hybrid
1309 Cell/B.E. debugging, you need to configure GDB to support both the
1310 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1311 --enable-targets configure option.
1313 * Non-stop mode debugging.
1315 For some targets, GDB now supports an optional mode of operation in
1316 which you can examine stopped threads while other threads continue
1317 to execute freely. This is referred to as non-stop mode, with the
1318 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1319 section in the user manual for more information.
1321 To be able to support remote non-stop debugging, a remote stub needs
1322 to implement the non-stop mode remote protocol extensions, as
1323 described in the "Remote Non-Stop" section of the user manual. The
1324 GDB remote stub, gdbserver, has been adjusted to support these
1325 extensions on linux targets.
1327 * New commands (for set/show, see "New options" below)
1329 catch syscall [NAME(S) | NUMBER(S)]
1330 Catch system calls. Arguments, which should be names of system
1331 calls or their numbers, mean catch only those syscalls. Without
1332 arguments, every syscall will be caught. When the inferior issues
1333 any of the specified syscalls, GDB will stop and announce the system
1334 call, both when it is called and when its call returns. This
1335 feature is currently available with a native GDB running on the
1336 Linux Kernel, under the following architectures: x86, x86_64,
1337 PowerPC and PowerPC64.
1339 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1341 Search memory for a sequence of bytes.
1343 maint set python print-stack
1344 maint show python print-stack
1345 Show a stack trace when an error is encountered in a Python script.
1348 Invoke CODE by passing it to the Python interpreter.
1353 These allow macros to be defined, undefined, and listed
1357 Show operating system information about processes.
1360 List the inferiors currently under GDB's control.
1363 Switch focus to inferior number NUM.
1366 Detach from inferior number NUM.
1369 Kill inferior number NUM.
1373 set spu stop-on-load
1374 show spu stop-on-load
1375 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1377 set spu auto-flush-cache
1378 show spu auto-flush-cache
1379 Control whether to automatically flush the software-managed cache
1380 during Cell/B.E. debugging.
1382 set sh calling-convention
1383 show sh calling-convention
1384 Control the calling convention used when calling SH target functions.
1387 show debug timestamp
1388 Control display of timestamps with GDB debugging output.
1390 set disassemble-next-line
1391 show disassemble-next-line
1392 Control display of disassembled source lines or instructions when
1395 set remote noack-packet
1396 show remote noack-packet
1397 Set/show the use of remote protocol QStartNoAckMode packet. See above
1398 under "New remote packets."
1400 set remote query-attached-packet
1401 show remote query-attached-packet
1402 Control use of remote protocol `qAttached' (query-attached) packet.
1404 set remote read-siginfo-object
1405 show remote read-siginfo-object
1406 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1409 set remote write-siginfo-object
1410 show remote write-siginfo-object
1411 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1414 set remote reverse-continue
1415 show remote reverse-continue
1416 Control use of remote protocol 'bc' (reverse-continue) packet.
1418 set remote reverse-step
1419 show remote reverse-step
1420 Control use of remote protocol 'bs' (reverse-step) packet.
1422 set displaced-stepping
1423 show displaced-stepping
1424 Control displaced stepping mode. Displaced stepping is a way to
1425 single-step over breakpoints without removing them from the debuggee.
1426 Also known as "out-of-line single-stepping".
1429 show debug displaced
1430 Control display of debugging info for displaced stepping.
1432 maint set internal-error
1433 maint show internal-error
1434 Control what GDB does when an internal error is detected.
1436 maint set internal-warning
1437 maint show internal-warning
1438 Control what GDB does when an internal warning is detected.
1443 Use a wrapper program to launch programs for debugging.
1445 set multiple-symbols (all|ask|cancel)
1446 show multiple-symbols
1447 The value of this variable can be changed to adjust the debugger behavior
1448 when an expression or a breakpoint location contains an ambiguous symbol
1449 name (an overloaded function name, for instance).
1451 set breakpoint always-inserted
1452 show breakpoint always-inserted
1453 Keep breakpoints always inserted in the target, as opposed to inserting
1454 them when resuming the target, and removing them when the target stops.
1455 This option can improve debugger performance on slow remote targets.
1457 set arm fallback-mode (arm|thumb|auto)
1458 show arm fallback-mode
1459 set arm force-mode (arm|thumb|auto)
1461 These commands control how ARM GDB determines whether instructions
1462 are ARM or Thumb. The default for both settings is auto, which uses
1463 the current CPSR value for instructions without symbols; previous
1464 versions of GDB behaved as if "set arm fallback-mode arm".
1466 set disable-randomization
1467 show disable-randomization
1468 Standalone programs run with the virtual address space randomization enabled
1469 by default on some platforms. This option keeps the addresses stable across
1470 multiple debugging sessions.
1474 Control whether other threads are stopped or not when some thread hits
1479 Requests that asynchronous execution is enabled in the target, if available.
1480 In this case, it's possible to resume target in the background, and interact
1481 with GDB while the target is running. "show target-async" displays the
1482 current state of asynchronous execution of the target.
1484 set target-wide-charset
1485 show target-wide-charset
1486 The target-wide-charset is the name of the character set that GDB
1487 uses when printing characters whose type is wchar_t.
1489 set tcp auto-retry (on|off)
1491 set tcp connect-timeout
1492 show tcp connect-timeout
1493 These commands allow GDB to retry failed TCP connections to a remote stub
1494 with a specified timeout period; this is useful if the stub is launched
1495 in parallel with GDB but may not be ready to accept connections immediately.
1497 set libthread-db-search-path
1498 show libthread-db-search-path
1499 Control list of directories which GDB will search for appropriate
1502 set schedule-multiple (on|off)
1503 show schedule-multiple
1504 Allow GDB to resume all threads of all processes or only threads of
1505 the current process.
1509 Use more aggressive caching for accesses to the stack. This improves
1510 performance of remote debugging (particularly backtraces) without
1511 affecting correctness.
1513 set interactive-mode (on|off|auto)
1514 show interactive-mode
1515 Control whether GDB runs in interactive mode (on) or not (off).
1516 When in interactive mode, GDB waits for the user to answer all
1517 queries. Otherwise, GDB does not wait and assumes the default
1518 answer. When set to auto (the default), GDB determines which
1519 mode to use based on the stdin settings.
1524 For program forks, this is replaced by the new more generic `info
1525 inferiors' command. To list checkpoints, you can still use the
1526 `info checkpoints' command, which was an alias for the `info forks'
1530 Replaced by the new `inferior' command. To switch between
1531 checkpoints, you can still use the `restart' command, which was an
1532 alias for the `fork' command.
1535 This is removed, since some targets don't have a notion of
1536 processes. To switch between processes, you can still use the
1537 `inferior' command using GDB's own inferior number.
1540 For program forks, this is replaced by the new more generic `kill
1541 inferior' command. To delete a checkpoint, you can still use the
1542 `delete checkpoint' command, which was an alias for the `delete
1546 For program forks, this is replaced by the new more generic `detach
1547 inferior' command. To detach a checkpoint, you can still use the
1548 `detach checkpoint' command, which was an alias for the `detach
1551 * New native configurations
1553 x86/x86_64 Darwin i[34567]86-*-darwin*
1555 x86_64 MinGW x86_64-*-mingw*
1559 Lattice Mico32 lm32-*
1560 x86 DICOS i[34567]86-*-dicos*
1561 x86_64 DICOS x86_64-*-dicos*
1564 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1565 (mingw32ce) debugging.
1571 These commands were actually not implemented on any target.
1573 *** Changes in GDB 6.8
1575 * New native configurations
1577 NetBSD/hppa hppa*-*netbsd*
1578 Xtensa GNU/Linux xtensa*-*-linux*
1582 NetBSD/hppa hppa*-*-netbsd*
1583 Xtensa GNU/Lunux xtensa*-*-linux*
1585 * Change in command line behavior -- corefiles vs. process ids.
1587 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1588 attaching to process NUMBER fails, GDB no longer attempts to open a
1589 core file named NUMBER. Attaching to a program using the -c option
1590 is no longer supported. Instead, use the '-p' or '--pid' options.
1592 * GDB can now be built as a native debugger for debugging Windows x86
1593 (mingw32) Portable Executable (PE) programs.
1595 * Pending breakpoints no longer change their number when their address
1598 * GDB now supports breakpoints with multiple locations,
1599 including breakpoints on C++ constructors, inside C++ templates,
1600 and in inlined functions.
1602 * GDB's ability to debug optimized code has been improved. GDB more
1603 accurately identifies function bodies and lexical blocks that occupy
1604 more than one contiguous range of addresses.
1606 * Target descriptions can now describe registers for PowerPC.
1608 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1609 registers on PowerPC targets.
1611 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1612 targets even when the libthread_db library is not available.
1614 * The GDB remote stub, gdbserver, now supports the new file transfer
1615 commands (remote put, remote get, and remote delete).
1617 * The GDB remote stub, gdbserver, now supports run and attach in
1618 extended-remote mode.
1620 * hppa*64*-*-hpux11* target broken
1621 The debugger is unable to start a program and fails with the following
1622 error: "Error trying to get information about dynamic linker".
1623 The gdb-6.7 release is also affected.
1625 * GDB now supports the --enable-targets= configure option to allow
1626 building a single GDB executable that supports multiple remote
1627 target architectures.
1629 * GDB now supports debugging C and C++ programs which use the
1630 Decimal Floating Point extension. In addition, the PowerPC target
1631 now has a set of pseudo-registers to inspect decimal float values
1632 stored in two consecutive float registers.
1634 * The -break-insert MI command can optionally create pending
1637 * Improved support for debugging Ada
1638 Many improvements to the Ada language support have been made. These
1640 - Better support for Ada2005 interface types
1641 - Improved handling of arrays and slices in general
1642 - Better support for Taft-amendment types
1643 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1645 - Improved command completion in Ada
1648 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1653 set print frame-arguments (all|scalars|none)
1654 show print frame-arguments
1655 The value of this variable can be changed to control which argument
1656 values should be printed by the debugger when displaying a frame.
1661 Transfer files to and from a remote target, and delete remote files.
1668 Transfer files to and from a remote target, and delete remote files.
1670 * New remote packets
1677 Open, close, read, write, and delete files on the remote system.
1680 Attach to an existing process on the remote system, in extended-remote
1684 Run a new process on the remote system, in extended-remote mode.
1686 *** Changes in GDB 6.7
1688 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1689 bfd, libiberty and opcodes, as revealed by static analysis donated by
1690 Coverity, Inc. (http://scan.coverity.com).
1692 * When looking up multiply-defined global symbols, GDB will now prefer the
1693 symbol definition in the current shared library if it was built using the
1694 -Bsymbolic linker option.
1696 * When the Text User Interface (TUI) is not configured, GDB will now
1697 recognize the -tui command-line option and print a message that the TUI
1700 * The GDB remote stub, gdbserver, now has lower overhead for high
1701 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1703 * GDB for MIPS targets now autodetects whether a remote target provides
1704 32-bit or 64-bit register values.
1706 * Support for C++ member pointers has been improved.
1708 * GDB now understands XML target descriptions, which specify the
1709 target's overall architecture. GDB can read a description from
1710 a local file or over the remote serial protocol.
1712 * Vectors of single-byte data use a new integer type which is not
1713 automatically displayed as character or string data.
1715 * The /s format now works with the print command. It displays
1716 arrays of single-byte integers and pointers to single-byte integers
1719 * Target descriptions can now describe target-specific registers,
1720 for architectures which have implemented the support (currently
1721 only ARM, M68K, and MIPS).
1723 * GDB and the GDB remote stub, gdbserver, now support the XScale
1726 * The GDB remote stub, gdbserver, has been updated to support
1727 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1728 has been rewritten to use the standard GDB remote protocol.
1730 * GDB can now step into C++ functions which are called through thunks.
1732 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1734 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1735 layout. It also supports a TextSeg= and DataSeg= response when only
1736 segment base addresses (rather than offsets) are available.
1738 * The /i format now outputs any trailing branch delay slot instructions
1739 immediately following the last instruction within the count specified.
1741 * The GDB remote protocol "T" stop reply packet now supports a
1742 "library" response. Combined with the new "qXfer:libraries:read"
1743 packet, this response allows GDB to debug shared libraries on targets
1744 where the operating system manages the list of loaded libraries (e.g.
1745 Windows and SymbianOS).
1747 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1748 (DLLs) on Windows and Windows CE targets.
1750 * GDB now supports a faster verification that a .debug file matches its binary
1751 according to its build-id signature, if the signature is present.
1757 Enable or disable hardware flow control (RTS/CTS) on the serial port
1758 when debugging using remote targets.
1760 set mem inaccessible-by-default
1761 show mem inaccessible-by-default
1762 If the target supplies a memory map, for instance via the remote
1763 protocol's "qXfer:memory-map:read" packet, setting this variable
1764 prevents GDB from accessing memory outside the memory map. This
1765 is useful for targets with memory mapped registers or which react
1766 badly to accesses of unmapped address space.
1768 set breakpoint auto-hw
1769 show breakpoint auto-hw
1770 If the target supplies a memory map, for instance via the remote
1771 protocol's "qXfer:memory-map:read" packet, setting this variable
1772 lets GDB use hardware breakpoints automatically for memory regions
1773 where it can not use software breakpoints. This covers both the
1774 "break" command and internal breakpoints used for other commands
1775 including "next" and "finish".
1778 catch exception unhandled
1779 Stop the program execution when Ada exceptions are raised.
1782 Stop the program execution when an Ada assertion failed.
1786 Set an alternate system root for target files. This is a more
1787 general version of "set solib-absolute-prefix", which is now
1788 an alias to "set sysroot".
1791 Provide extended SPU facility status information. This set of
1792 commands is available only when debugging the Cell/B.E. SPU
1795 * New native configurations
1797 OpenBSD/sh sh*-*openbsd*
1800 unset tdesc filename
1802 Use the specified local file as an XML target description, and do
1803 not query the target for its built-in description.
1807 OpenBSD/sh sh*-*-openbsd*
1808 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1809 Toshiba Media Processor mep-elf
1811 * New remote packets
1814 Ignore the specified signals; pass them directly to the debugged program
1815 without stopping other threads or reporting them to GDB.
1817 qXfer:features:read:
1818 Read an XML target description from the target, which describes its
1823 Read or write contents of an spufs file on the target system. These
1824 packets are available only on the Cell/B.E. SPU architecture.
1826 qXfer:libraries:read:
1827 Report the loaded shared libraries. Combined with new "T" packet
1828 response, this packet allows GDB to debug shared libraries on
1829 targets where the operating system manages the list of loaded
1830 libraries (e.g. Windows and SymbianOS).
1834 Support for these obsolete configurations has been removed.
1842 i[34567]86-*-lynxos*
1843 i[34567]86-*-netware*
1844 i[34567]86-*-sco3.2v5*
1845 i[34567]86-*-sco3.2v4*
1847 i[34567]86-*-sysv4.2*
1850 i[34567]86-*-unixware2*
1851 i[34567]86-*-unixware*
1860 * Other removed features
1867 Various m68k-only ROM monitors.
1874 Various Renesas ROM monitors and debugging interfaces for SH and
1879 Support for a Macraigor serial interface to on-chip debugging.
1880 GDB does not directly support the newer parallel or USB
1885 A debug information format. The predecessor to DWARF 2 and
1886 DWARF 3, which are still supported.
1888 Support for the HP aCC compiler on HP-UX/PA-RISC
1890 SOM-encapsulated symbolic debugging information, automatic
1891 invocation of pxdb, and the aCC custom C++ ABI. This does not
1892 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1893 with aCC can still be debugged on an assembly level.
1895 MIPS ".pdr" sections
1897 A MIPS-specific format used to describe stack frame layout
1898 in debugging information.
1902 GDB could work with an older version of Guile to debug
1903 the interpreter and Scheme programs running in it.
1905 set mips stack-arg-size
1906 set mips saved-gpreg-size
1908 Use "set mips abi" to control parameter passing for MIPS.
1910 *** Changes in GDB 6.6
1915 Cell Broadband Engine SPU spu-elf
1917 * GDB can now be configured as a cross-debugger targeting native Windows
1918 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1919 running on a Windows system over TCP/IP to debug Windows programs.
1921 * The GDB remote stub, gdbserver, has been updated to support Windows and
1922 Cygwin debugging. Both single-threaded and multi-threaded programs are
1925 * The "set trust-readonly-sections" command works again. This command was
1926 broken in GDB 6.3, 6.4, and 6.5.
1928 * The "load" command now supports writing to flash memory, if the remote
1929 stub provides the required support.
1931 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1932 longer requires symbolic debug information (e.g. DWARF-2).
1937 unset substitute-path
1938 show substitute-path
1939 Manage a list of substitution rules that GDB uses to rewrite the name
1940 of the directories where the sources are located. This can be useful
1941 for instance when the sources were moved to a different location
1942 between compilation and debugging.
1946 Print each CLI command as it is executed. Each command is prefixed with
1947 a number of `+' symbols representing the nesting depth.
1948 The source command now has a `-v' option to enable the same feature.
1952 The ARM Demon monitor support (RDP protocol, "target rdp").
1954 Kernel Object Display, an embedded debugging feature which only worked with
1955 an obsolete version of Cisco IOS.
1957 The 'set download-write-size' and 'show download-write-size' commands.
1959 * New remote packets
1962 Tell a stub about GDB client features, and request remote target features.
1963 The first feature implemented is PacketSize, which allows the target to
1964 specify the size of packets it can handle - to minimize the number of
1965 packets required and improve performance when connected to a remote
1969 Fetch an OS auxilliary vector from the remote stub. This packet is a
1970 more efficient replacement for qPart:auxv:read.
1972 qXfer:memory-map:read:
1973 Fetch a memory map from the remote stub, including information about
1974 RAM, ROM, and flash memory devices.
1979 Erase and program a flash memory device.
1981 * Removed remote packets
1984 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1985 used it, and only gdbserver implemented it.
1987 *** Changes in GDB 6.5
1991 Renesas M32C/M16C m32c-elf
1993 Morpho Technologies ms1 ms1-elf
1997 init-if-undefined Initialize a convenience variable, but
1998 only if it doesn't already have a value.
2000 The following commands are presently only implemented for native GNU/Linux:
2002 checkpoint Save a snapshot of the program state.
2004 restart <n> Return the program state to a
2005 previously saved state.
2007 info checkpoints List currently saved checkpoints.
2009 delete-checkpoint <n> Delete a previously saved checkpoint.
2011 set|show detach-on-fork Tell gdb whether to detach from a newly
2012 forked process, or to keep debugging it.
2014 info forks List forks of the user program that
2015 are available to be debugged.
2017 fork <n> Switch to debugging one of several
2018 forks of the user program that are
2019 available to be debugged.
2021 delete-fork <n> Delete a fork from the list of forks
2022 that are available to be debugged (and
2023 kill the forked process).
2025 detach-fork <n> Delete a fork from the list of forks
2026 that are available to be debugged (and
2027 allow the process to continue).
2031 Morpho Technologies ms2 ms1-elf
2033 * Improved Windows host support
2035 GDB now builds as a cross debugger hosted on i686-mingw32, including
2036 native console support, and remote communications using either
2037 network sockets or serial ports.
2039 * Improved Modula-2 language support
2041 GDB can now print most types in the Modula-2 syntax. This includes:
2042 basic types, set types, record types, enumerated types, range types,
2043 pointer types and ARRAY types. Procedure var parameters are correctly
2044 printed and hexadecimal addresses and character constants are also
2045 written in the Modula-2 syntax. Best results can be obtained by using
2046 GNU Modula-2 together with the -gdwarf-2 command line option.
2050 The ARM rdi-share module.
2052 The Netware NLM debug server.
2054 *** Changes in GDB 6.4
2056 * New native configurations
2058 OpenBSD/arm arm*-*-openbsd*
2059 OpenBSD/mips64 mips64-*-openbsd*
2063 Morpho Technologies ms1 ms1-elf
2065 * New command line options
2067 --batch-silent As for --batch, but totally silent.
2068 --return-child-result The debugger will exist with the same value
2069 the child (debugged) program exited with.
2070 --eval-command COMMAND, -ex COMMAND
2071 Execute a single GDB CLI command. This may be
2072 specified multiple times and in conjunction
2073 with the --command (-x) option.
2075 * Deprecated commands removed
2077 The following commands, that were deprecated in 2000, have been
2081 set|show arm disassembly-flavor set|show arm disassembler
2082 othernames set arm disassembler
2083 set|show remotedebug set|show debug remote
2084 set|show archdebug set|show debug arch
2085 set|show eventdebug set|show debug event
2088 * New BSD user-level threads support
2090 It is now possible to debug programs using the user-level threads
2091 library on OpenBSD and FreeBSD. Currently supported (target)
2094 FreeBSD/amd64 x86_64-*-freebsd*
2095 FreeBSD/i386 i386-*-freebsd*
2096 OpenBSD/i386 i386-*-openbsd*
2098 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2099 are not yet supported.
2101 * New support for Matsushita MN10300 w/sim added
2102 (Work in progress). mn10300-elf.
2104 * REMOVED configurations and files
2106 VxWorks and the XDR protocol *-*-vxworks
2107 Motorola MCORE mcore-*-*
2108 National Semiconductor NS32000 ns32k-*-*
2110 * New "set print array-indexes" command
2112 After turning this setting "on", GDB prints the index of each element
2113 when displaying arrays. The default is "off" to preserve the previous
2116 * VAX floating point support
2118 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2120 * User-defined command support
2122 In addition to using $arg0..$arg9 for argument passing, it is now possible
2123 to use $argc to determine now many arguments have been passed. See the
2124 section on user-defined commands in the user manual for more information.
2126 *** Changes in GDB 6.3:
2128 * New command line option
2130 GDB now accepts -l followed by a number to set the timeout for remote
2133 * GDB works with GCC -feliminate-dwarf2-dups
2135 GDB now supports a more compact representation of DWARF-2 debug
2136 information using DW_FORM_ref_addr references. These are produced
2137 by GCC with the option -feliminate-dwarf2-dups and also by some
2138 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2139 to use -feliminate-dwarf2-dups.
2141 * Internationalization
2143 When supported by the host system, GDB will be built with
2144 internationalization (libintl). The task of marking up the sources is
2145 continued, we're looking forward to our first translation.
2149 Initial support for debugging programs compiled with the GNAT
2150 implementation of the Ada programming language has been integrated
2151 into GDB. In this release, support is limited to expression evaluation.
2153 * New native configurations
2155 GNU/Linux/m32r m32r-*-linux-gnu
2159 GDB's remote protocol now includes support for the 'p' packet. This
2160 packet is used to fetch individual registers from a remote inferior.
2162 * END-OF-LIFE registers[] compatibility module
2164 GDB's internal register infrastructure has been completely rewritten.
2165 The new infrastructure making possible the implementation of key new
2166 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2169 GDB 6.3 will be the last release to include the the registers[]
2170 compatibility module that allowed out-of-date configurations to
2171 continue to work. This change directly impacts the following
2181 powerpc bdm protocol
2183 Unless there is activity to revive these configurations, they will be
2184 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2186 * OBSOLETE configurations and files
2188 Configurations that have been declared obsolete in this release have
2189 been commented out. Unless there is activity to revive these
2190 configurations, the next release of GDB will have their sources
2191 permanently REMOVED.
2200 *** Changes in GDB 6.2.1:
2202 * MIPS `break main; run' gave an heuristic-fence-post warning
2204 When attempting to run even a simple program, a warning about
2205 heuristic-fence-post being hit would be reported. This problem has
2208 * MIPS IRIX 'long double' crashed GDB
2210 When examining a long double variable, GDB would get a segmentation
2211 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2212 IRIX long double values).
2216 A bug in the VAX stack code was causing problems with the "next"
2217 command. This problem has been fixed.
2219 *** Changes in GDB 6.2:
2221 * Fix for ``many threads''
2223 On GNU/Linux systems that use the NPTL threads library, a program
2224 rapidly creating and deleting threads would confuse GDB leading to the
2227 ptrace: No such process.
2228 thread_db_get_info: cannot get thread info: generic error
2230 This problem has been fixed.
2232 * "-async" and "-noasync" options removed.
2234 Support for the broken "-noasync" option has been removed (it caused
2237 * New ``start'' command.
2239 This command runs the program until the begining of the main procedure.
2241 * New BSD Kernel Data Access Library (libkvm) interface
2243 Using ``target kvm'' it is now possible to debug kernel core dumps and
2244 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2245 platforms. Currently supported (native-only) configurations are:
2247 FreeBSD/amd64 x86_64-*-freebsd*
2248 FreeBSD/i386 i?86-*-freebsd*
2249 NetBSD/i386 i?86-*-netbsd*
2250 NetBSD/m68k m68*-*-netbsd*
2251 NetBSD/sparc sparc-*-netbsd*
2252 OpenBSD/amd64 x86_64-*-openbsd*
2253 OpenBSD/i386 i?86-*-openbsd*
2254 OpenBSD/m68k m68*-openbsd*
2255 OpenBSD/sparc sparc-*-openbsd*
2257 * Signal trampoline code overhauled
2259 Many generic problems with GDB's signal handling code have been fixed.
2260 These include: backtraces through non-contiguous stacks; recognition
2261 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2262 call; backtrace through a signal trampoline; step into and out of
2263 signal handlers; and single-stepping in the signal trampoline.
2265 Please note that kernel bugs are a limiting factor here. These
2266 features have been shown to work on an s390 GNU/Linux system that
2267 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2269 * Cygwin support for DWARF 2 added.
2271 * New native configurations
2273 GNU/Linux/hppa hppa*-*-linux*
2274 OpenBSD/hppa hppa*-*-openbsd*
2275 OpenBSD/m68k m68*-*-openbsd*
2276 OpenBSD/m88k m88*-*-openbsd*
2277 OpenBSD/powerpc powerpc-*-openbsd*
2278 NetBSD/vax vax-*-netbsd*
2279 OpenBSD/vax vax-*-openbsd*
2281 * END-OF-LIFE frame compatibility module
2283 GDB's internal frame infrastructure has been completely rewritten.
2284 The new infrastructure making it possible to support key new features
2285 including DWARF 2 Call Frame Information. To aid in the task of
2286 migrating old configurations to this new infrastructure, a
2287 compatibility module, that allowed old configurations to continue to
2288 work, was also included.
2290 GDB 6.2 will be the last release to include this frame compatibility
2291 module. This change directly impacts the following configurations:
2301 Unless there is activity to revive these configurations, they will be
2302 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2304 * REMOVED configurations and files
2306 Sun 3, running SunOS 3 m68*-*-sunos3*
2307 Sun 3, running SunOS 4 m68*-*-sunos4*
2308 Sun 2, running SunOS 3 m68000-*-sunos3*
2309 Sun 2, running SunOS 4 m68000-*-sunos4*
2310 Motorola 680x0 running LynxOS m68*-*-lynxos*
2311 AT&T 3b1/Unix pc m68*-att-*
2312 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2313 decstation mips-dec-* mips-little-*
2314 riscos mips-*-riscos* mips-*-sysv*
2315 sonymips mips-sony-*
2316 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2318 *** Changes in GDB 6.1.1:
2320 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2322 The TUI (Text-mode User Interface) is now built as part of a default
2323 GDB configuration. It is enabled by either selecting the TUI with the
2324 command line option "-i=tui" or by running the separate "gdbtui"
2325 program. For more information on the TUI, see the manual "Debugging
2328 * Pending breakpoint support (also included in GDB 6.1)
2330 Support has been added to allow you to specify breakpoints in shared
2331 libraries that have not yet been loaded. If a breakpoint location
2332 cannot be found, and the "breakpoint pending" option is set to auto,
2333 GDB queries you if you wish to make the breakpoint pending on a future
2334 shared-library load. If and when GDB resolves the breakpoint symbol,
2335 the pending breakpoint is removed as one or more regular breakpoints
2338 Pending breakpoints are very useful for GCJ Java debugging.
2340 * Fixed ISO-C build problems
2342 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2343 non ISO-C code that stopped them being built using a more strict ISO-C
2344 compiler (e.g., IBM's C compiler).
2346 * Fixed build problem on IRIX 5
2348 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2349 wasn't able to compile compile on an IRIX 5 system.
2351 * Added execute permission to gdb/gdbserver/configure
2353 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2354 permission. This bug would cause configure to fail on a number of
2355 systems (Solaris, IRIX). Ref: server/519.
2357 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2359 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2360 has been updated to use constant array sizes.
2362 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2364 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2365 its generated DWARF Call Frame Info. This encoding was causing GDB to
2366 panic, that panic has been fixed. Ref: gdb/1628.
2368 * Fixed a problem when examining parameters in shared library code.
2370 When examining parameters in optimized shared library code generated
2371 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2372 not available''. GDB now correctly displays the variable's value.
2374 *** Changes in GDB 6.1:
2376 * Removed --with-mmalloc
2378 Support for the mmalloc memory manager has been removed, as it
2379 conflicted with the internal gdb byte cache.
2381 * Changes in AMD64 configurations
2383 The AMD64 target now includes the %cs and %ss registers. As a result
2384 the AMD64 remote protocol has changed; this affects the floating-point
2385 and SSE registers. If you rely on those registers for your debugging,
2386 you should upgrade gdbserver on the remote side.
2388 * Revised SPARC target
2390 The SPARC target has been completely revised, incorporating the
2391 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2392 support for LynxOS and SunOS 4 has been dropped. Calling functions
2393 from within GDB on operating systems with a non-executable stack
2394 (Solaris, OpenBSD) now works.
2398 GDB has a new C++ demangler which does a better job on the mangled
2399 names generated by current versions of g++. It also runs faster, so
2400 with this and other changes gdb should now start faster on large C++
2403 * DWARF 2 Location Expressions
2405 GDB support for location expressions has been extended to support function
2406 arguments and frame bases. Older versions of GDB could crash when they
2409 * C++ nested types and namespaces
2411 GDB's support for nested types and namespaces in C++ has been
2412 improved, especially if you use the DWARF 2 debugging format. (This
2413 is the default for recent versions of GCC on most platforms.)
2414 Specifically, if you have a class "Inner" defined within a class or
2415 namespace "Outer", then GDB realizes that the class's name is
2416 "Outer::Inner", not simply "Inner". This should greatly reduce the
2417 frequency of complaints about not finding RTTI symbols. In addition,
2418 if you are stopped at inside of a function defined within a namespace,
2419 GDB modifies its name lookup accordingly.
2421 * New native configurations
2423 NetBSD/amd64 x86_64-*-netbsd*
2424 OpenBSD/amd64 x86_64-*-openbsd*
2425 OpenBSD/alpha alpha*-*-openbsd*
2426 OpenBSD/sparc sparc-*-openbsd*
2427 OpenBSD/sparc64 sparc64-*-openbsd*
2429 * New debugging protocols
2431 M32R with SDI protocol m32r-*-elf*
2433 * "set prompt-escape-char" command deleted.
2435 The command "set prompt-escape-char" has been deleted. This command,
2436 and its very obscure effet on GDB's prompt, was never documented,
2437 tested, nor mentioned in the NEWS file.
2439 * OBSOLETE configurations and files
2441 Configurations that have been declared obsolete in this release have
2442 been commented out. Unless there is activity to revive these
2443 configurations, the next release of GDB will have their sources
2444 permanently REMOVED.
2446 Sun 3, running SunOS 3 m68*-*-sunos3*
2447 Sun 3, running SunOS 4 m68*-*-sunos4*
2448 Sun 2, running SunOS 3 m68000-*-sunos3*
2449 Sun 2, running SunOS 4 m68000-*-sunos4*
2450 Motorola 680x0 running LynxOS m68*-*-lynxos*
2451 AT&T 3b1/Unix pc m68*-att-*
2452 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2453 decstation mips-dec-* mips-little-*
2454 riscos mips-*-riscos* mips-*-sysv*
2455 sonymips mips-sony-*
2456 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2458 * REMOVED configurations and files
2460 SGI Irix-4.x mips-sgi-irix4 or iris4
2461 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2462 Z8000 simulator z8k-zilog-none or z8ksim
2463 Matsushita MN10200 w/simulator mn10200-*-*
2464 H8/500 simulator h8500-hitachi-hms or h8500hms
2465 HP/PA running BSD hppa*-*-bsd*
2466 HP/PA running OSF/1 hppa*-*-osf*
2467 HP/PA Pro target hppa*-*-pro*
2468 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2469 386BSD i[3456]86-*-bsd*
2470 Sequent family i[3456]86-sequent-sysv4*
2471 i[3456]86-sequent-sysv*
2472 i[3456]86-sequent-bsd*
2473 SPARC running LynxOS sparc-*-lynxos*
2474 SPARC running SunOS 4 sparc-*-sunos4*
2475 Tsqware Sparclet sparclet-*-*
2476 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2478 *** Changes in GDB 6.0:
2482 Support for debugging the Objective-C programming language has been
2483 integrated into GDB.
2485 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2487 DWARF 2's Call Frame Information makes available compiler generated
2488 information that more exactly describes the program's run-time stack.
2489 By using this information, GDB is able to provide more robust stack
2492 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2493 have been updated to use a new backtrace mechanism which includes
2494 DWARF 2 CFI support.
2498 GDB's remote protocol has been extended to include support for hosted
2499 file I/O (where the remote target uses GDB's file system). See GDB's
2500 remote protocol documentation for details.
2502 * All targets using the new architecture framework.
2504 All of GDB's targets have been updated to use the new internal
2505 architecture framework. The way is now open for future GDB releases
2506 to include cross-architecture native debugging support (i386 on amd64,
2509 * GNU/Linux's Thread Local Storage (TLS)
2511 GDB now includes support for for the GNU/Linux implementation of
2512 per-thread variables.
2514 * GNU/Linux's Native POSIX Thread Library (NPTL)
2516 GDB's thread code has been updated to work with either the new
2517 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2519 * Separate debug info.
2521 GDB, in conjunction with BINUTILS, now supports a mechanism for
2522 automatically loading debug information from a separate file. Instead
2523 of shipping full debug and non-debug versions of system libraries,
2524 system integrators can now instead ship just the stripped libraries
2525 and optional debug files.
2527 * DWARF 2 Location Expressions
2529 DWARF 2 Location Expressions allow the compiler to more completely
2530 describe the location of variables (even in optimized code) to the
2533 GDB now includes preliminary support for location expressions (support
2534 for DW_OP_piece is still missing).
2538 A number of long standing bugs that caused GDB to die while starting a
2539 Java application have been fixed. GDB's Java support is now
2540 considered "useable".
2542 * GNU/Linux support for fork, vfork, and exec.
2544 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2545 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2548 * GDB supports logging output to a file
2550 There are two new commands, "set logging" and "show logging", which can be
2551 used to capture GDB's output to a file.
2553 * The meaning of "detach" has changed for gdbserver
2555 The "detach" command will now resume the application, as documented. To
2556 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2559 * d10v, m68hc11 `regs' command deprecated
2561 The `info registers' command has been updated so that it displays the
2562 registers using a format identical to the old `regs' command.
2566 A new command, "maint set profile on/off", has been added. This command can
2567 be used to enable or disable profiling while running GDB, to profile a
2568 session or a set of commands. In addition there is a new configure switch,
2569 "--enable-profiling", which will cause GDB to be compiled with profiling
2570 data, for more informative profiling results.
2572 * Default MI syntax changed to "mi2".
2574 The default MI (machine interface) syntax, enabled by the command line
2575 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2576 "mi1", can be enabled by specifying the option "-i=mi1".
2578 Support for the original "mi0" syntax (included in GDB 5.0) has been
2581 Fix for gdb/192: removed extraneous space when displaying frame level.
2582 Fix for gdb/672: update changelist is now output in mi list format.
2583 Fix for gdb/702: a -var-assign that updates the value now shows up
2584 in a subsequent -var-update.
2586 * New native configurations.
2588 FreeBSD/amd64 x86_64-*-freebsd*
2590 * Multi-arched targets.
2592 HP/PA HPUX11 hppa*-*-hpux*
2593 Renesas M32R/D w/simulator m32r-*-elf*
2595 * OBSOLETE configurations and files
2597 Configurations that have been declared obsolete in this release have
2598 been commented out. Unless there is activity to revive these
2599 configurations, the next release of GDB will have their sources
2600 permanently REMOVED.
2602 Z8000 simulator z8k-zilog-none or z8ksim
2603 Matsushita MN10200 w/simulator mn10200-*-*
2604 H8/500 simulator h8500-hitachi-hms or h8500hms
2605 HP/PA running BSD hppa*-*-bsd*
2606 HP/PA running OSF/1 hppa*-*-osf*
2607 HP/PA Pro target hppa*-*-pro*
2608 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2609 Sequent family i[3456]86-sequent-sysv4*
2610 i[3456]86-sequent-sysv*
2611 i[3456]86-sequent-bsd*
2612 Tsqware Sparclet sparclet-*-*
2613 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2615 * REMOVED configurations and files
2618 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2619 IBM AIX PS/2 i[3456]86-*-aix
2620 i386 running Mach 3.0 i[3456]86-*-mach3*
2621 i386 running Mach i[3456]86-*-mach*
2622 i386 running OSF/1 i[3456]86-*osf1mk*
2623 HP/Apollo 68k Family m68*-apollo*-sysv*,
2625 m68*-hp-bsd*, m68*-hp-hpux*
2626 Argonaut Risc Chip (ARC) arc-*-*
2627 Mitsubishi D30V d30v-*-*
2628 Fujitsu FR30 fr30-*-elf*
2629 OS/9000 i[34]86-*-os9k
2630 I960 with MON960 i960-*-coff
2632 * MIPS $fp behavior changed
2634 The convenience variable $fp, for the MIPS, now consistently returns
2635 the address of the current frame's base. Previously, depending on the
2636 context, $fp could refer to either $sp or the current frame's base
2637 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2638 The GNU Source-Level Debugger''.
2640 *** Changes in GDB 5.3:
2642 * GNU/Linux shared library multi-threaded performance improved.
2644 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2645 `/proc', in preference to `ptrace' for memory reads. This may result
2646 in an improvement in the start-up time of multi-threaded, shared
2647 library applications when run under GDB. One GDB user writes: ``loads
2648 shared libs like mad''.
2650 * ``gdbserver'' now supports multi-threaded applications on some targets
2652 Support for debugging multi-threaded applications which use
2653 the GNU/Linux LinuxThreads package has been added for
2654 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2655 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2657 * GDB now supports C/C++ preprocessor macros.
2659 GDB now expands preprocessor macro invocations in C/C++ expressions,
2660 and provides various commands for showing macro definitions and how
2663 The new command `macro expand EXPRESSION' expands any macro
2664 invocations in expression, and shows the result.
2666 The new command `show macro MACRO-NAME' shows the definition of the
2667 macro named MACRO-NAME, and where it was defined.
2669 Most compilers don't include information about macros in the debugging
2670 information by default. In GCC 3.1, for example, you need to compile
2671 your program with the options `-gdwarf-2 -g3'. If the macro
2672 information is present in the executable, GDB will read it.
2674 * Multi-arched targets.
2676 DEC Alpha (partial) alpha*-*-*
2677 DEC VAX (partial) vax-*-*
2679 National Semiconductor NS32000 (partial) ns32k-*-*
2680 Motorola 68000 (partial) m68k-*-*
2681 Motorola MCORE mcore-*-*
2685 Fujitsu FRV architecture added by Red Hat frv*-*-*
2688 * New native configurations
2690 Alpha NetBSD alpha*-*-netbsd*
2691 SH NetBSD sh*-*-netbsdelf*
2692 MIPS NetBSD mips*-*-netbsd*
2693 UltraSPARC NetBSD sparc64-*-netbsd*
2695 * OBSOLETE configurations and files
2697 Configurations that have been declared obsolete in this release have
2698 been commented out. Unless there is activity to revive these
2699 configurations, the next release of GDB will have their sources
2700 permanently REMOVED.
2702 Mitsubishi D30V d30v-*-*
2703 OS/9000 i[34]86-*-os9k
2704 IBM AIX PS/2 i[3456]86-*-aix
2705 Fujitsu FR30 fr30-*-elf*
2706 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2707 Argonaut Risc Chip (ARC) arc-*-*
2708 i386 running Mach 3.0 i[3456]86-*-mach3*
2709 i386 running Mach i[3456]86-*-mach*
2710 i386 running OSF/1 i[3456]86-*osf1mk*
2711 HP/Apollo 68k Family m68*-apollo*-sysv*,
2713 m68*-hp-bsd*, m68*-hp-hpux*
2714 I960 with MON960 i960-*-coff
2716 * OBSOLETE languages
2718 CHILL, a Pascal like language used by telecommunications companies.
2720 * REMOVED configurations and files
2722 AMD 29k family via UDI a29k-amd-udi, udi29k
2723 A29K VxWorks a29k-*-vxworks
2724 AMD 29000 embedded, using EBMON a29k-none-none
2725 AMD 29000 embedded with COFF a29k-none-coff
2726 AMD 29000 embedded with a.out a29k-none-aout
2728 testsuite/gdb.hp/gdb.threads-hp/ directory
2730 * New command "set max-user-call-depth <nnn>"
2732 This command allows the user to limit the call depth of user-defined
2733 commands. The default is 1024.
2735 * Changes in FreeBSD/i386 native debugging.
2737 Support for the "generate-core-file" has been added.
2739 * New commands "dump", "append", and "restore".
2741 These commands allow data to be copied from target memory
2742 to a bfd-format or binary file (dump and append), and back
2743 from a file into memory (restore).
2745 * Improved "next/step" support on multi-processor Alpha Tru64.
2747 The previous single-step mechanism could cause unpredictable problems,
2748 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2749 of a software single-step mechanism prevents this.
2751 *** Changes in GDB 5.2.1:
2759 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2760 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2761 Fix, by Joel Brobecker imported from mainline.
2763 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2764 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2765 Fix, by Fred Fish, imported from mainline.
2767 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2768 Surprisingly enough, it works now.
2769 By Michal Ludvig, imported from mainline.
2771 i386 hardware watchpoint support:
2772 avoid misses on second run for some targets.
2773 By Pierre Muller, imported from mainline.
2775 *** Changes in GDB 5.2:
2777 * New command "set trust-readonly-sections on[off]".
2779 This command is a hint that tells gdb that read-only sections
2780 really are read-only (ie. that their contents will not change).
2781 In this mode, gdb will go to the object file rather than the
2782 target to read memory from read-only sections (such as ".text").
2783 This can be a significant performance improvement on some
2784 (notably embedded) targets.
2786 * New command "generate-core-file" (or "gcore").
2788 This new gdb command allows the user to drop a core file of the child
2789 process state at any time. So far it's been implemented only for
2790 GNU/Linux and Solaris, but should be relatively easily ported to other
2791 hosts. Argument is core file name (defaults to core.<pid>).
2793 * New command line option
2795 GDB now accepts --pid or -p followed by a process id.
2797 * Change in command line behavior -- corefiles vs. process ids.
2799 There is a subtle behavior in the way in which GDB handles
2800 command line arguments. The first non-flag argument is always
2801 a program to debug, but the second non-flag argument may either
2802 be a corefile or a process id. Previously, GDB would attempt to
2803 open the second argument as a corefile, and if that failed, would
2804 issue a superfluous error message and then attempt to attach it as
2805 a process. Now, if the second argument begins with a non-digit,
2806 it will be treated as a corefile. If it begins with a digit,
2807 GDB will attempt to attach it as a process, and if no such process
2808 is found, will then attempt to open it as a corefile.
2810 * Changes in ARM configurations.
2812 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2813 configuration is fully multi-arch.
2815 * New native configurations
2817 ARM NetBSD arm*-*-netbsd*
2818 x86 OpenBSD i[3456]86-*-openbsd*
2819 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2820 Sparc64 running FreeBSD sparc64-*-freebsd*
2824 Sanyo XStormy16 xstormy16-elf
2826 * OBSOLETE configurations and files
2828 Configurations that have been declared obsolete in this release have
2829 been commented out. Unless there is activity to revive these
2830 configurations, the next release of GDB will have their sources
2831 permanently REMOVED.
2833 AMD 29k family via UDI a29k-amd-udi, udi29k
2834 A29K VxWorks a29k-*-vxworks
2835 AMD 29000 embedded, using EBMON a29k-none-none
2836 AMD 29000 embedded with COFF a29k-none-coff
2837 AMD 29000 embedded with a.out a29k-none-aout
2839 testsuite/gdb.hp/gdb.threads-hp/ directory
2841 * REMOVED configurations and files
2843 TI TMS320C80 tic80-*-*
2845 PowerPC Solaris powerpcle-*-solaris*
2846 PowerPC Windows NT powerpcle-*-cygwin32
2847 PowerPC Netware powerpc-*-netware*
2848 Harris/CXUX m88k m88*-harris-cxux*
2849 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2850 ns32k-utek-sysv* ns32k-utek-*
2851 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2852 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2853 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2854 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2855 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2857 * Changes to command line processing
2859 The new `--args' feature can be used to specify command-line arguments
2860 for the inferior from gdb's command line.
2862 * Changes to key bindings
2864 There is a new `operate-and-get-next' function bound to `C-o'.
2866 *** Changes in GDB 5.1.1
2868 Fix compile problem on DJGPP.
2870 Fix a problem with floating-point registers on the i386 being
2873 Fix to stop GDB crashing on .debug_str debug info.
2875 Numerous documentation fixes.
2877 Numerous testsuite fixes.
2879 *** Changes in GDB 5.1:
2881 * New native configurations
2883 Alpha FreeBSD alpha*-*-freebsd*
2884 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2885 MIPS GNU/Linux mips*-*-linux*
2886 MIPS SGI Irix 6.x mips*-sgi-irix6*
2887 ia64 AIX ia64-*-aix*
2888 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2892 Motorola 68HC11 and 68HC12 m68hc11-elf
2894 UltraSparc running GNU/Linux sparc64-*-linux*
2896 * OBSOLETE configurations and files
2898 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2899 Harris/CXUX m88k m88*-harris-cxux*
2900 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2901 ns32k-utek-sysv* ns32k-utek-*
2902 TI TMS320C80 tic80-*-*
2904 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2905 PowerPC Solaris powerpcle-*-solaris*
2906 PowerPC Windows NT powerpcle-*-cygwin32
2907 PowerPC Netware powerpc-*-netware*
2908 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2909 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2910 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2911 Apple Macintosh (MPW) host N/A
2913 stuff.c (Program to stuff files into a specially prepared space in kdb)
2914 kdb-start.c (Main loop for the standalone kernel debugger)
2916 Configurations that have been declared obsolete in this release have
2917 been commented out. Unless there is activity to revive these
2918 configurations, the next release of GDB will have their sources
2919 permanently REMOVED.
2921 * REMOVED configurations and files
2923 Altos 3068 m68*-altos-*
2924 Convex c1-*-*, c2-*-*
2926 ARM RISCix arm-*-* (as host)
2930 * GDB has been converted to ISO C.
2932 GDB's source code has been converted to ISO C. In particular, the
2933 sources are fully protoized, and rely on standard headers being
2938 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2940 * The MI enabled by default.
2942 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2943 revised and enabled by default. Packages which use GDB as a debugging
2944 engine behind a UI or another front end are encouraged to switch to
2945 using the GDB/MI interface, instead of the old annotations interface
2946 which is now deprecated.
2948 * Support for debugging Pascal programs.
2950 GDB now includes support for debugging Pascal programs. The following
2951 main features are supported:
2953 - Pascal-specific data types such as sets;
2955 - automatic recognition of Pascal sources based on file-name
2958 - Pascal-style display of data types, variables, and functions;
2960 - a Pascal expression parser.
2962 However, some important features are not yet supported.
2964 - Pascal string operations are not supported at all;
2966 - there are some problems with boolean types;
2968 - Pascal type hexadecimal constants are not supported
2969 because they conflict with the internal variables format;
2971 - support for Pascal objects and classes is not full yet;
2973 - unlike Pascal, GDB is case-sensitive for symbol names.
2975 * Changes in completion.
2977 Commands such as `shell', `run' and `set args', which pass arguments
2978 to inferior programs, now complete on file names, similar to what
2979 users expect at the shell prompt.
2981 Commands which accept locations, such as `disassemble', `print',
2982 `breakpoint', `until', etc. now complete on filenames as well as
2983 program symbols. Thus, if you type "break foob TAB", and the source
2984 files linked into the programs include `foobar.c', that file name will
2985 be one of the candidates for completion. However, file names are not
2986 considered for completion after you typed a colon that delimits a file
2987 name from a name of a function in that file, as in "break foo.c:bar".
2989 `set demangle-style' completes on available demangling styles.
2991 * New platform-independent commands:
2993 It is now possible to define a post-hook for a command as well as a
2994 hook that runs before the command. For more details, see the
2995 documentation of `hookpost' in the GDB manual.
2997 * Changes in GNU/Linux native debugging.
2999 Support for debugging multi-threaded programs has been completely
3000 revised for all platforms except m68k and sparc. You can now debug as
3001 many threads as your system allows you to have.
3003 Attach/detach is supported for multi-threaded programs.
3005 Support for SSE registers was added for x86. This doesn't work for
3006 multi-threaded programs though.
3008 * Changes in MIPS configurations.
3010 Multi-arch support is enabled for all MIPS configurations.
3012 GDB can now be built as native debugger on SGI Irix 6.x systems for
3013 debugging n32 executables. (Debugging 64-bit executables is not yet
3016 * Unified support for hardware watchpoints in all x86 configurations.
3018 Most (if not all) native x86 configurations support hardware-assisted
3019 breakpoints and watchpoints in a unified manner. This support
3020 implements debug register sharing between watchpoints, which allows to
3021 put a virtually infinite number of watchpoints on the same address,
3022 and also supports watching regions up to 16 bytes with several debug
3025 The new maintenance command `maintenance show-debug-regs' toggles
3026 debugging print-outs in functions that insert, remove, and test
3027 watchpoints and hardware breakpoints.
3029 * Changes in the DJGPP native configuration.
3031 New command ``info dos sysinfo'' displays assorted information about
3032 the CPU, OS, memory, and DPMI server.
3034 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3035 display information about segment descriptors stored in GDT, LDT, and
3038 New commands ``info dos pde'' and ``info dos pte'' display entries
3039 from Page Directory and Page Tables (for now works with CWSDPMI only).
3040 New command ``info dos address-pte'' displays the Page Table entry for
3041 a given linear address.
3043 GDB can now pass command lines longer than 126 characters to the
3044 program being debugged (requires an update to the libdbg.a library
3045 which is part of the DJGPP development kit).
3047 DWARF2 debug info is now supported.
3049 It is now possible to `step' and `next' through calls to `longjmp'.
3051 * Changes in documentation.
3053 All GDB documentation was converted to GFDL, the GNU Free
3054 Documentation License.
3056 Tracepoints-related commands are now fully documented in the GDB
3059 TUI, the Text-mode User Interface, is now documented in the manual.
3061 Tracepoints-related commands are now fully documented in the GDB
3064 The "GDB Internals" manual now has an index. It also includes
3065 documentation of `ui_out' functions, GDB coding standards, x86
3066 hardware watchpoints, and memory region attributes.
3068 * GDB's version number moved to ``version.in''
3070 The Makefile variable VERSION has been replaced by the file
3071 ``version.in''. People creating GDB distributions should update the
3072 contents of this file.
3076 GUD support is now a standard part of the EMACS distribution.
3078 *** Changes in GDB 5.0:
3080 * Improved support for debugging FP programs on x86 targets
3082 Unified and much-improved support for debugging floating-point
3083 programs on all x86 targets. In particular, ``info float'' now
3084 displays the FP registers in the same format on all x86 targets, with
3085 greater level of detail.
3087 * Improvements and bugfixes in hardware-assisted watchpoints
3089 It is now possible to watch array elements, struct members, and
3090 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3091 on x86 targets no longer erroneously trigger when the address is
3094 * Improvements in the native DJGPP version of GDB
3096 The distribution now includes all the scripts and auxiliary files
3097 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3098 machines ``out of the box''.
3100 The DJGPP version can now debug programs that use signals. It is
3101 possible to catch signals that happened in the debuggee, deliver
3102 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3103 would kill the program being debugged.) Programs that hook hardware
3104 interrupts (keyboard, timer, etc.) can also be debugged.
3106 It is now possible to debug DJGPP programs that redirect their
3107 standard handles or switch them to raw (as opposed to cooked) mode, or
3108 even close them. The command ``run < foo > bar'' works as expected,
3109 and ``info terminal'' reports useful information about the debuggee's
3110 terminal, including raw/cooked mode, redirection, etc.
3112 The DJGPP version now uses termios functions for console I/O, which
3113 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3116 DOS-style file names with drive letters are now fully supported by
3119 It is now possible to debug DJGPP programs that switch their working
3120 directory. It is also possible to rerun the debuggee any number of
3121 times without restarting GDB; thus, you can use the same setup,
3122 breakpoints, etc. for many debugging sessions.
3124 * New native configurations
3126 ARM GNU/Linux arm*-*-linux*
3127 PowerPC GNU/Linux powerpc-*-linux*
3131 Motorola MCore mcore-*-*
3132 x86 VxWorks i[3456]86-*-vxworks*
3133 PowerPC VxWorks powerpc-*-vxworks*
3134 TI TMS320C80 tic80-*-*
3136 * OBSOLETE configurations
3138 Altos 3068 m68*-altos-*
3139 Convex c1-*-*, c2-*-*
3141 ARM RISCix arm-*-* (as host)
3144 Configurations that have been declared obsolete will be commented out,
3145 but the code will be left in place. If there is no activity to revive
3146 these configurations before the next release of GDB, the sources will
3147 be permanently REMOVED.
3149 * Gould support removed
3151 Support for the Gould PowerNode and NP1 has been removed.
3153 * New features for SVR4
3155 On SVR4 native platforms (such as Solaris), if you attach to a process
3156 without first loading a symbol file, GDB will now attempt to locate and
3157 load symbols from the running process's executable file.
3159 * Many C++ enhancements
3161 C++ support has been greatly improved. Overload resolution now works properly
3162 in almost all cases. RTTI support is on the way.
3164 * Remote targets can connect to a sub-program
3166 A popen(3) style serial-device has been added. This device starts a
3167 sub-process (such as a stand-alone simulator) and then communicates
3168 with that. The sub-program to run is specified using the syntax
3169 ``|<program> <args>'' vis:
3171 (gdb) set remotedebug 1
3172 (gdb) target extended-remote |mn10300-elf-sim program-args
3174 * MIPS 64 remote protocol
3176 A long standing bug in the mips64 remote protocol where by GDB
3177 expected certain 32 bit registers (ex SR) to be transfered as 32
3178 instead of 64 bits has been fixed.
3180 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3181 added to provide backward compatibility with older versions of GDB.
3183 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3185 The command ``set remotebinarydownload'' command has been replaced by
3186 ``set remote X-packet''. Other commands in ``set remote'' family
3187 include ``set remote P-packet''.
3189 * Breakpoint commands accept ranges.
3191 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3192 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3193 ``tracepoint passcount'' also accepts a range of tracepoints.
3195 * ``apropos'' command added.
3197 The ``apropos'' command searches through command names and
3198 documentation strings, printing out matches, making it much easier to
3199 try to find a command that does what you are looking for.
3203 A new machine oriented interface (MI) has been added to GDB. This
3204 interface is designed for debug environments running GDB as a separate
3205 process. This is part of the long term libGDB project. See the
3206 "GDB/MI" chapter of the GDB manual for further information. It can be
3207 enabled by configuring with:
3209 .../configure --enable-gdbmi
3211 *** Changes in GDB-4.18:
3213 * New native configurations
3215 HP-UX 10.20 hppa*-*-hpux10.20
3216 HP-UX 11.x hppa*-*-hpux11.0*
3217 M68K GNU/Linux m68*-*-linux*
3221 Fujitsu FR30 fr30-*-elf*
3222 Intel StrongARM strongarm-*-*
3223 Mitsubishi D30V d30v-*-*
3225 * OBSOLETE configurations
3227 Gould PowerNode, NP1 np1-*-*, pn-*-*
3229 Configurations that have been declared obsolete will be commented out,
3230 but the code will be left in place. If there is no activity to revive
3231 these configurations before the next release of GDB, the sources will
3232 be permanently REMOVED.
3236 As a compatibility experiment, GDB's source files buildsym.h and
3237 buildsym.c have been converted to pure standard C, no longer
3238 containing any K&R compatibility code. We believe that all systems in
3239 use today either come with a standard C compiler, or have a GCC port
3240 available. If this is not true, please report the affected
3241 configuration to bug-gdb@gnu.org immediately. See the README file for
3242 information about getting a standard C compiler if you don't have one
3247 GDB now uses readline 2.2.
3249 * set extension-language
3251 You can now control the mapping between filename extensions and source
3252 languages by using the `set extension-language' command. For instance,
3253 you can ask GDB to treat .c files as C++ by saying
3254 set extension-language .c c++
3255 The command `info extensions' lists all of the recognized extensions
3256 and their associated languages.
3258 * Setting processor type for PowerPC and RS/6000
3260 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3261 you can use the `set processor' command to specify what variant of the
3262 PowerPC family you are debugging. The command
3266 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3267 following PowerPC and RS6000 variants:
3269 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3270 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3272 403GC IBM PowerPC 403GC
3273 505 Motorola PowerPC 505
3274 860 Motorola PowerPC 860 or 850
3275 601 Motorola PowerPC 601
3276 602 Motorola PowerPC 602
3277 603 Motorola/IBM PowerPC 603 or 603e
3278 604 Motorola PowerPC 604 or 604e
3279 750 Motorola/IBM PowerPC 750 or 750
3281 At the moment, this command just tells GDB what to name the
3282 special-purpose processor registers. Since almost all the affected
3283 registers are inaccessible to user-level programs, this command is
3284 only useful for remote debugging in its present form.
3288 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3289 more extensive support for HP-UX. Added features include shared
3290 library support, kernel threads and hardware watchpoints for 11.00,
3291 support for HP's ANSI C and C++ compilers, and a compatibility mode
3292 for xdb and dbx commands.
3296 HP's donation includes the new concept of catchpoints, which is a
3297 generalization of the old catch command. On HP-UX, it is now possible
3298 to catch exec, fork, and vfork, as well as library loading.
3300 This means that the existing catch command has changed; its first
3301 argument now specifies the type of catch to be set up. See the
3302 output of "help catch" for a list of catchpoint types.
3304 * Debugging across forks
3306 On HP-UX, you can choose which process to debug when a fork() happens
3311 HP has donated a curses-based terminal user interface (TUI). To get
3312 it, build with --enable-tui. Although this can be enabled for any
3313 configuration, at present it only works for native HP debugging.
3315 * GDB remote protocol additions
3317 A new protocol packet 'X' that writes binary data is now available.
3318 Default behavior is to try 'X', then drop back to 'M' if the stub
3319 fails to respond. The settable variable `remotebinarydownload'
3320 allows explicit control over the use of 'X'.
3322 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3323 full 64-bit address. The command
3325 set remoteaddresssize 32
3327 can be used to revert to the old behaviour. For existing remote stubs
3328 the change should not be noticed, as the additional address information
3331 In order to assist in debugging stubs, you may use the maintenance
3332 command `packet' to send any text string to the stub. For instance,
3334 maint packet heythere
3336 sends the packet "$heythere#<checksum>". Note that it is very easy to
3337 disrupt a debugging session by sending the wrong packet at the wrong
3340 The compare-sections command allows you to compare section data on the
3341 target to what is in the executable file without uploading or
3342 downloading, by comparing CRC checksums.
3344 * Tracing can collect general expressions
3346 You may now collect general expressions at tracepoints. This requires
3347 further additions to the target-side stub; see tracepoint.c and
3348 doc/agentexpr.texi for further details.
3350 * mask-address variable for Mips
3352 For Mips targets, you may control the zeroing of the upper 32 bits of
3353 a 64-bit address by entering `set mask-address on'. This is mainly
3354 of interest to users of embedded R4xxx and R5xxx processors.
3356 * Higher serial baud rates
3358 GDB's serial code now allows you to specify baud rates 57600, 115200,
3359 230400, and 460800 baud. (Note that your host system may not be able
3360 to achieve all of these rates.)
3364 The i960 configuration now includes an initial implementation of a
3365 builtin simulator, contributed by Jim Wilson.
3368 *** Changes in GDB-4.17:
3370 * New native configurations
3372 Alpha GNU/Linux alpha*-*-linux*
3373 Unixware 2.x i[3456]86-unixware2*
3374 Irix 6.x mips*-sgi-irix6*
3375 PowerPC GNU/Linux powerpc-*-linux*
3376 PowerPC Solaris powerpcle-*-solaris*
3377 Sparc GNU/Linux sparc-*-linux*
3378 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3382 Argonaut Risc Chip (ARC) arc-*-*
3383 Hitachi H8/300S h8300*-*-*
3384 Matsushita MN10200 w/simulator mn10200-*-*
3385 Matsushita MN10300 w/simulator mn10300-*-*
3386 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3387 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3388 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3389 Mitsubishi D10V w/simulator d10v-*-*
3390 Mitsubishi M32R/D w/simulator m32r-*-elf*
3391 Tsqware Sparclet sparclet-*-*
3392 NEC V850 w/simulator v850-*-*
3394 * New debugging protocols
3396 ARM with RDI protocol arm*-*-*
3397 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3398 DDB and LSI variants of PMON protocol mips*-*-*
3399 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3400 PowerPC with SDS protocol powerpc{,le}-*-eabi
3401 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3405 All configurations can now understand and use the DWARF 2 debugging
3406 format. The choice is automatic, if the symbol file contains DWARF 2
3411 GDB now includes basic Java language support. This support is
3412 only useful with Java compilers that produce native machine code.
3414 * solib-absolute-prefix and solib-search-path
3416 For SunOS and SVR4 shared libraries, you may now set the prefix for
3417 loading absolute shared library symbol files, and the search path for
3418 locating non-absolute shared library symbol files.
3420 * Live range splitting
3422 GDB can now effectively debug code for which GCC has performed live
3423 range splitting as part of its optimization. See gdb/doc/LRS for
3424 more details on the expected format of the stabs information.
3428 GDB's support for the GNU Hurd, including thread debugging, has been
3429 updated to work with current versions of the Hurd.
3433 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3434 instruction set. ARM GDB automatically detects when Thumb
3435 instructions are in use, and adjusts disassembly and backtracing
3440 GDB's MIPS target configurations now handle the MIP16 16-bit
3445 GDB now includes support for overlays; if an executable has been
3446 linked such that multiple sections are based at the same address, GDB
3447 will decide which section to use for symbolic info. You can choose to
3448 control the decision manually, using overlay commands, or implement
3449 additional target-side support and use "overlay load-target" to bring
3450 in the overlay mapping. Do "help overlay" for more detail.
3454 The command "info symbol <address>" displays information about
3455 the symbol at the specified address.
3459 The standard remote protocol now includes an extension that allows
3460 asynchronous collection and display of trace data. This requires
3461 extensive support in the target-side debugging stub. Tracing mode
3462 includes a new interaction mode in GDB and new commands: see the
3463 file tracepoint.c for more details.
3467 Configurations for embedded MIPS now include a simulator contributed
3468 by Cygnus Solutions. The simulator supports the instruction sets
3469 of most MIPS variants.
3473 Sparc configurations may now include the ERC32 simulator contributed
3474 by the European Space Agency. The simulator is not built into
3475 Sparc targets by default; configure with --enable-sim to include it.
3479 For target configurations that may include multiple variants of a
3480 basic architecture (such as MIPS and SH), you may now set the
3481 architecture explicitly. "set arch" sets, "info arch" lists
3482 the possible architectures.
3484 *** Changes in GDB-4.16:
3486 * New native configurations
3488 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3489 M68K NetBSD m68k-*-netbsd*
3490 PowerPC AIX 4.x powerpc-*-aix*
3491 PowerPC MacOS powerpc-*-macos*
3492 PowerPC Windows NT powerpcle-*-cygwin32
3493 RS/6000 AIX 4.x rs6000-*-aix4*
3497 ARM with RDP protocol arm-*-*
3498 I960 with MON960 i960-*-coff
3499 MIPS VxWorks mips*-*-vxworks*
3500 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3501 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3503 Matra Sparclet sparclet-*-*
3507 The powerpc-eabi configuration now includes the PSIM simulator,
3508 contributed by Andrew Cagney, with assistance from Mike Meissner.
3509 PSIM is a very elaborate model of the PowerPC, including not only
3510 basic instruction set execution, but also details of execution unit
3511 performance and I/O hardware. See sim/ppc/README for more details.
3515 GDB now works with Solaris 2.5.
3517 * Windows 95/NT native
3519 GDB will now work as a native debugger on Windows 95 and Windows NT.
3520 To build it from source, you must use the "gnu-win32" environment,
3521 which uses a DLL to emulate enough of Unix to run the GNU tools.
3522 Further information, binaries, and sources are available at
3523 ftp.cygnus.com, under pub/gnu-win32.
3525 * dont-repeat command
3527 If a user-defined command includes the command `dont-repeat', then the
3528 command will not be repeated if the user just types return. This is
3529 useful if the command is time-consuming to run, so that accidental
3530 extra keystrokes don't run the same command many times.
3532 * Send break instead of ^C
3534 The standard remote protocol now includes an option to send a break
3535 rather than a ^C to the target in order to interrupt it. By default,
3536 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3538 * Remote protocol timeout
3540 The standard remote protocol includes a new variable `remotetimeout'
3541 that allows you to set the number of seconds before GDB gives up trying
3542 to read from the target. The default value is 2.
3544 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3546 By default GDB will automatically keep track of objects as they are
3547 loaded and unloaded by the dynamic linker. By using the command `set
3548 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3549 when shared library events occur, thus allowing you to set breakpoints
3550 in shared libraries which are explicitly loaded by the inferior.
3552 Note this feature does not work on hpux8. On hpux9 you must link
3553 /usr/lib/end.o into your program. This feature should work
3554 automatically on hpux10.
3556 * Irix 5.x hardware watchpoint support
3558 Irix 5 configurations now support the use of hardware watchpoints.
3560 * Mips protocol "SYN garbage limit"
3562 When debugging a Mips target using the `target mips' protocol, you
3563 may set the number of characters that GDB will ignore by setting
3564 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3565 every character. The default value is 1050.
3567 * Recording and replaying remote debug sessions
3569 If you set `remotelogfile' to the name of a file, gdb will write to it
3570 a recording of a remote debug session. This recording may then be
3571 replayed back to gdb using "gdbreplay". See gdbserver/README for
3572 details. This is useful when you have a problem with GDB while doing
3573 remote debugging; you can make a recording of the session and send it
3574 to someone else, who can then recreate the problem.
3576 * Speedups for remote debugging
3578 GDB includes speedups for downloading and stepping MIPS systems using
3579 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3580 and more efficient S-record downloading.
3582 * Memory use reductions and statistics collection
3584 GDB now uses less memory and reports statistics about memory usage.
3585 Try the `maint print statistics' command, for example.
3587 *** Changes in GDB-4.15:
3589 * Psymtabs for XCOFF
3591 The symbol reader for AIX GDB now uses partial symbol tables. This
3592 can greatly improve startup time, especially for large executables.
3594 * Remote targets use caching
3596 Remote targets now use a data cache to speed up communication with the
3597 remote side. The data cache could lead to incorrect results because
3598 it doesn't know about volatile variables, thus making it impossible to
3599 debug targets which use memory mapped I/O devices. `set remotecache
3600 off' turns the the data cache off.
3602 * Remote targets may have threads
3604 The standard remote protocol now includes support for multiple threads
3605 in the target system, using new protocol commands 'H' and 'T'. See
3606 gdb/remote.c for details.
3610 If GDB is configured with `--enable-netrom', then it will include
3611 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3612 acts as though it is a bank of ROM on the target board, but you can
3613 write into it over the network. GDB's support consists only of
3614 support for fast loading into the emulated ROM; to debug, you must use
3615 another protocol, such as standard remote protocol. The usual
3616 sequence is something like
3618 target nrom <netrom-hostname>
3620 target remote <netrom-hostname>:1235
3624 GDB now includes support for the Apple Macintosh, as a host only. It
3625 may be run as either an MPW tool or as a standalone application, and
3626 it can debug through the serial port. All the usual GDB commands are
3627 available, but to the target command, you must supply "serial" as the
3628 device type instead of "/dev/ttyXX". See mpw-README in the main
3629 directory for more information on how to build. The MPW configuration
3630 scripts */mpw-config.in support only a few targets, and only the
3631 mips-idt-ecoff target has been tested.
3635 GDB configuration now uses autoconf. This is not user-visible,
3636 but does simplify configuration and building.
3640 GDB now supports hpux10.
3642 *** Changes in GDB-4.14:
3644 * New native configurations
3646 x86 FreeBSD i[345]86-*-freebsd
3647 x86 NetBSD i[345]86-*-netbsd
3648 NS32k NetBSD ns32k-*-netbsd
3649 Sparc NetBSD sparc-*-netbsd
3653 A29K VxWorks a29k-*-vxworks
3654 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3655 CPU32 EST-300 emulator m68*-*-est*
3656 PowerPC ELF powerpc-*-elf
3659 * Alpha OSF/1 support for procfs
3661 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3662 possible to attach to running processes. As the mounting of the /proc
3663 filesystem is optional on the Alpha, GDB automatically determines
3664 the availability of /proc during startup. This can lead to problems
3665 if /proc is unmounted after GDB has been started.
3667 * Arguments to user-defined commands
3669 User commands may accept up to 10 arguments separated by whitespace.
3670 Arguments are accessed within the user command via $arg0..$arg9. A
3673 print $arg0 + $arg1 + $arg2
3675 To execute the command use:
3678 Defines the command "adder" which prints the sum of its three arguments.
3679 Note the arguments are text substitutions, so they may reference variables,
3680 use complex expressions, or even perform inferior function calls.
3682 * New `if' and `while' commands
3684 This makes it possible to write more sophisticated user-defined
3685 commands. Both commands take a single argument, which is the
3686 expression to evaluate, and must be followed by the commands to
3687 execute, one per line, if the expression is nonzero, the list being
3688 terminated by the word `end'. The `if' command list may include an
3689 `else' word, which causes the following commands to be executed only
3690 if the expression is zero.
3692 * Fortran source language mode
3694 GDB now includes partial support for Fortran 77. It will recognize
3695 Fortran programs and can evaluate a subset of Fortran expressions, but
3696 variables and functions may not be handled correctly. GDB will work
3697 with G77, but does not yet know much about symbols emitted by other
3700 * Better HPUX support
3702 Most debugging facilities now work on dynamic executables for HPPAs
3703 running hpux9 or later. You can attach to running dynamically linked
3704 processes, but by default the dynamic libraries will be read-only, so
3705 for instance you won't be able to put breakpoints in them. To change
3706 that behavior do the following before running the program:
3712 This will cause the libraries to be mapped private and read-write.
3713 To revert to the normal behavior, do this:
3719 You cannot set breakpoints or examine data in the library until after
3720 the library is loaded if the function/data symbols do not have
3723 GDB can now also read debug symbols produced by the HP C compiler on
3724 HPPAs (sorry, no C++, Fortran or 68k support).
3726 * Target byte order now dynamically selectable
3728 You can choose which byte order to use with a target system, via the
3729 commands "set endian big" and "set endian little", and you can see the
3730 current setting by using "show endian". You can also give the command
3731 "set endian auto", in which case GDB will use the byte order
3732 associated with the executable. Currently, only embedded MIPS
3733 configurations support dynamic selection of target byte order.
3735 * New DOS host serial code
3737 This version uses DPMI interrupts to handle buffered I/O, so you
3738 no longer need to run asynctsr when debugging boards connected to
3741 *** Changes in GDB-4.13:
3743 * New "complete" command
3745 This lists all the possible completions for the rest of the line, if it
3746 were to be given as a command itself. This is intended for use by emacs.
3748 * Trailing space optional in prompt
3750 "set prompt" no longer adds a space for you after the prompt you set. This
3751 allows you to set a prompt which ends in a space or one that does not.
3753 * Breakpoint hit counts
3755 "info break" now displays a count of the number of times the breakpoint
3756 has been hit. This is especially useful in conjunction with "ignore"; you
3757 can ignore a large number of breakpoint hits, look at the breakpoint info
3758 to see how many times the breakpoint was hit, then run again, ignoring one
3759 less than that number, and this will get you quickly to the last hit of
3762 * Ability to stop printing at NULL character
3764 "set print null-stop" will cause GDB to stop printing the characters of
3765 an array when the first NULL is encountered. This is useful when large
3766 arrays actually contain only short strings.
3768 * Shared library breakpoints
3770 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3771 breakpoints in shared libraries before the executable is run.
3773 * Hardware watchpoints
3775 There is a new hardware breakpoint for the watch command for sparclite
3776 targets. See gdb/sparclite/hw_breakpoint.note.
3778 Hardware watchpoints are also now supported under GNU/Linux.
3782 Annotations have been added. These are for use with graphical interfaces,
3783 and are still experimental. Currently only gdba.el uses these.
3785 * Improved Irix 5 support
3787 GDB now works properly with Irix 5.2.
3789 * Improved HPPA support
3791 GDB now works properly with the latest GCC and GAS.
3793 * New native configurations
3795 Sequent PTX4 i[34]86-sequent-ptx4
3796 HPPA running OSF/1 hppa*-*-osf*
3797 Atari TT running SVR4 m68*-*-sysv4*
3798 RS/6000 LynxOS rs6000-*-lynxos*
3802 OS/9000 i[34]86-*-os9k
3803 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3806 * Hitachi SH7000 and E7000-PC ICE support
3808 There is now support for communicating with the Hitachi E7000-PC ICE.
3809 This is available automatically when GDB is configured for the SH.
3813 As usual, a variety of small fixes and improvements, both generic
3814 and configuration-specific. See the ChangeLog for more detail.
3816 *** Changes in GDB-4.12:
3818 * Irix 5 is now supported
3822 GDB-4.12 on the HPPA has a number of changes which make it unable
3823 to debug the output from the currently released versions of GCC and
3824 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3825 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3826 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3829 *** Changes in GDB-4.11:
3831 * User visible changes:
3835 The "set remotedebug" option is now consistent between the mips remote
3836 target, remote targets using the gdb-specific protocol, UDI (AMD's
3837 debug protocol for the 29k) and the 88k bug monitor. It is now an
3838 integer specifying a debug level (normally 0 or 1, but 2 means more
3839 debugging info for the mips target).
3841 * DEC Alpha native support
3843 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3844 debug info, but GDB works fairly well with the DEC compiler and should
3845 work with a future GCC release. See the README file for a few
3846 Alpha-specific notes.
3848 * Preliminary thread implementation
3850 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3852 * LynxOS native and target support for 386
3854 This release has been hosted on LynxOS 2.2, and also can be configured
3855 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3858 * Improvements in C++ mangling/demangling.
3860 This release has much better g++ debugging, specifically in name
3861 mangling/demangling, virtual function calls, print virtual table,
3862 call methods, ...etc.
3864 *** Changes in GDB-4.10:
3866 * User visible changes:
3868 Remote debugging using the GDB-specific (`target remote') protocol now
3869 supports the `load' command. This is only useful if you have some
3870 other way of getting the stub to the target system, and you can put it
3871 somewhere in memory where it won't get clobbered by the download.
3873 Filename completion now works.
3875 When run under emacs mode, the "info line" command now causes the
3876 arrow to point to the line specified. Also, "info line" prints
3877 addresses in symbolic form (as well as hex).
3879 All vxworks based targets now support a user settable option, called
3880 vxworks-timeout. This option represents the number of seconds gdb
3881 should wait for responses to rpc's. You might want to use this if
3882 your vxworks target is, perhaps, a slow software simulator or happens
3883 to be on the far side of a thin network line.
3887 This release contains support for using a DEC alpha as a GDB host for
3888 cross debugging. Native alpha debugging is not supported yet.
3891 *** Changes in GDB-4.9:
3895 This is the first GDB release which is accompanied by a matching testsuite.
3896 The testsuite requires installation of dejagnu, which should be available
3897 via ftp from most sites that carry GNU software.
3901 'Cfront' style demangling has had its name changed to 'ARM' style, to
3902 emphasize that it was written from the specifications in the C++ Annotated
3903 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3904 disclaimers, it still generated too much confusion with users attempting to
3905 use gdb with AT&T cfront.
3909 GDB now uses a standard remote interface to a simulator library.
3910 So far, the library contains simulators for the Zilog Z8001/2, the
3911 Hitachi H8/300, H8/500 and Super-H.
3913 * New targets supported
3915 H8/300 simulator h8300-hitachi-hms or h8300hms
3916 H8/500 simulator h8500-hitachi-hms or h8500hms
3917 SH simulator sh-hitachi-hms or sh
3918 Z8000 simulator z8k-zilog-none or z8ksim
3919 IDT MIPS board over serial line mips-idt-ecoff
3921 Cross-debugging to GO32 targets is supported. It requires a custom
3922 version of the i386-stub.c module which is integrated with the
3923 GO32 memory extender.
3925 * New remote protocols
3927 MIPS remote debugging protocol.
3929 * New source languages supported
3931 This version includes preliminary support for Chill, a Pascal like language
3932 used by telecommunications companies. Chill support is also being integrated
3933 into the GNU compiler, but we don't know when it will be publically available.
3936 *** Changes in GDB-4.8:
3938 * HP Precision Architecture supported
3940 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3941 version of this support was available as a set of patches from the
3942 University of Utah. GDB does not support debugging of programs
3943 compiled with the HP compiler, because HP will not document their file
3944 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3945 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3947 Many problems in the preliminary version have been fixed.
3949 * Faster and better demangling
3951 We have improved template demangling and fixed numerous bugs in the GNU style
3952 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3953 character types (wchar_t) are now supported. Demangling of each symbol is now
3954 only done once, and is cached when the symbol table for a file is read in.
3955 This results in a small increase in memory usage for C programs, a moderate
3956 increase in memory usage for C++ programs, and a fantastic speedup in
3959 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3960 from the specifications in the Annotated Reference Manual, which AT&T's
3961 compiler does not actually implement.
3963 * G++ multiple inheritance compiler problem
3965 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3966 inheritance lattices was reworked to properly discover ambiguities. We
3967 recently found an example which causes this new algorithm to fail in a
3968 very subtle way, producing bad debug information for those classes.
3969 The file 'gcc.patch' (in this directory) can be applied to gcc to
3970 circumvent the problem. A future GCC release will contain a complete
3973 The previous G++ debug info problem (mentioned below for the gdb-4.7
3974 release) is fixed in gcc version 2.3.2.
3976 * Improved configure script
3978 The `configure' script will now attempt to guess your system type if
3979 you don't supply a host system type. The old scheme of supplying a
3980 host system triplet is preferable over using this. All the magic is
3981 done in the new `config.guess' script. Examine it for details.
3983 We have also brought our configure script much more in line with the FSF's
3984 version. It now supports the --with-xxx options. In particular,
3985 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3986 The resulting GDB will not be able to read arbitrary object file formats --
3987 only the format ``expected'' to be used on the configured target system.
3988 We hope to make this the default in a future release.
3990 * Documentation improvements
3992 There's new internal documentation on how to modify GDB, and how to
3993 produce clean changes to the code. We implore people to read it
3994 before submitting changes.
3996 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3997 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3998 `info' files are also provided. To build `info' files from scratch,
3999 you will need the latest `makeinfo' release, which will be available in
4000 a future texinfo-X.Y release.
4002 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4003 We're not sure exactly which versions have this problem, but it has
4004 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4005 or better. If that isn't possible, there is a patch in
4006 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4007 around this problem.
4011 GDB now supports array constants that can be used in expressions typed in by
4012 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4013 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4016 The new directory `gdb/sparclite' contains a program that demonstrates
4017 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4019 * New native hosts supported
4021 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4022 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4024 * New targets supported
4026 AMD 29k family via UDI a29k-amd-udi or udi29k
4028 * New file formats supported
4030 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4031 HPUX core files, and SCO 3.2v2 core files.
4035 Attaching to processes now works again; thanks for the many bug reports.
4037 We have also stomped on a bunch of core dumps caused by
4038 printf_filtered("%s") problems.
4040 We eliminated a copyright problem on the rpc and ptrace header files
4041 for VxWorks, which was discovered at the last minute during the 4.7
4042 release. You should now be able to build a VxWorks GDB.
4044 You can now interrupt gdb while an attached process is running. This
4045 will cause the attached process to stop, and give control back to GDB.
4047 We fixed problems caused by using too many file descriptors
4048 for reading symbols from object files and libraries. This was
4049 especially a problem for programs that used many (~100) shared
4052 The `step' command now only enters a subroutine if there is line number
4053 information for the subroutine. Otherwise it acts like the `next'
4054 command. Previously, `step' would enter subroutines if there was
4055 any debugging information about the routine. This avoids problems
4056 when using `cc -g1' on MIPS machines.
4058 * Internal improvements
4060 GDB's internal interfaces have been improved to make it easier to support
4061 debugging of multiple languages in the future.
4063 GDB now uses a common structure for symbol information internally.
4064 Minimal symbols (derived from linkage symbols in object files), partial
4065 symbols (from a quick scan of debug information), and full symbols
4066 contain a common subset of information, making it easier to write
4067 shared code that handles any of them.
4069 * New command line options
4071 We now accept --silent as an alias for --quiet.
4075 The memory-mapped-malloc library is now licensed under the GNU Library
4076 General Public License.
4078 *** Changes in GDB-4.7:
4080 * Host/native/target split
4082 GDB has had some major internal surgery to untangle the support for
4083 hosts and remote targets. Now, when you configure GDB for a remote
4084 target, it will no longer load in all of the support for debugging
4085 local programs on the host. When fully completed and tested, this will
4086 ensure that arbitrary host/target combinations are possible.
4088 The primary conceptual shift is to separate the non-portable code in
4089 GDB into three categories. Host specific code is required any time GDB
4090 is compiled on that host, regardless of the target. Target specific
4091 code relates to the peculiarities of the target, but can be compiled on
4092 any host. Native specific code is everything else: it can only be
4093 built when the host and target are the same system. Child process
4094 handling and core file support are two common `native' examples.
4096 GDB's use of /proc for controlling Unix child processes is now cleaner.
4097 It has been split out into a single module under the `target_ops' vector,
4098 plus two native-dependent functions for each system that uses /proc.
4100 * New hosts supported
4102 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4103 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4104 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4106 * New targets supported
4108 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4109 68030 and CPU32 m68030-*-*, m68332-*-*
4111 * New native hosts supported
4113 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4114 (386bsd is not well tested yet)
4115 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4117 * New file formats supported
4119 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4120 supports reading of `a.out.adobe' object files, which are an a.out
4121 format extended with minimal information about multiple sections.
4125 `show copying' is the same as the old `info copying'.
4126 `show warranty' is the same as `info warrantee'.
4127 These were renamed for consistency. The old commands continue to work.
4129 `info handle' is a new alias for `info signals'.
4131 You can now define pre-command hooks, which attach arbitrary command
4132 scripts to any command. The commands in the hook will be executed
4133 prior to the user's command. You can also create a hook which will be
4134 executed whenever the program stops. See gdb.texinfo.
4138 We now deal with Cfront style name mangling, and can even extract type
4139 info from mangled symbols. GDB can automatically figure out which
4140 symbol mangling style your C++ compiler uses.
4142 Calling of methods and virtual functions has been improved as well.
4146 The crash that occured when debugging Sun Ansi-C compiled binaries is
4147 fixed. This was due to mishandling of the extra N_SO stabs output
4150 We also finally got Ultrix 4.2 running in house, and fixed core file
4151 support, with help from a dozen people on the net.
4153 John M. Farrell discovered that the reason that single-stepping was so
4154 slow on all of the Mips based platforms (primarily SGI and DEC) was
4155 that we were trying to demangle and lookup a symbol used for internal
4156 purposes on every instruction that was being stepped through. Changing
4157 the name of that symbol so that it couldn't be mistaken for a C++
4158 mangled symbol sped things up a great deal.
4160 Rich Pixley sped up symbol lookups in general by getting much smarter
4161 about when C++ symbol mangling is necessary. This should make symbol
4162 completion (TAB on the command line) much faster. It's not as fast as
4163 we'd like, but it's significantly faster than gdb-4.6.
4167 A new user controllable variable 'call_scratch_address' can
4168 specify the location of a scratch area to be used when GDB
4169 calls a function in the target. This is necessary because the
4170 usual method of putting the scratch area on the stack does not work
4171 in systems that have separate instruction and data spaces.
4173 We integrated changes to support the 29k UDI (Universal Debugger
4174 Interface), but discovered at the last minute that we didn't have all
4175 of the appropriate copyright paperwork. We are working with AMD to
4176 resolve this, and hope to have it available soon.
4180 We have sped up the remote serial line protocol, especially for targets
4181 with lots of registers. It now supports a new `expedited status' ('T')
4182 message which can be used in place of the existing 'S' status message.
4183 This allows the remote stub to send only the registers that GDB
4184 needs to make a quick decision about single-stepping or conditional
4185 breakpoints, eliminating the need to fetch the entire register set for
4186 each instruction being stepped through.
4188 The GDB remote serial protocol now implements a write-through cache for
4189 registers, only re-reading the registers if the target has run.
4191 There is also a new remote serial stub for SPARC processors. You can
4192 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4193 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4194 processor with a serial port.
4198 Configure.in files have become much easier to read and modify. A new
4199 `table driven' format makes it more obvious what configurations are
4200 supported, and what files each one uses.
4204 There is a new opcodes library which will eventually contain all of the
4205 disassembly routines and opcode tables. At present, it only contains
4206 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4207 disassembler (binutils/objdump) to share these routines.
4209 The libiberty library is now copylefted under the GNU Library General
4210 Public License. This allows more liberal use, and was done so libg++
4211 can use it. This makes no difference to GDB, since the Library License
4212 grants all the rights from the General Public License.
4216 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4217 reference to the stabs symbol info used by the debugger. It is (as far
4218 as we know) the only published document on this fascinating topic. We
4219 encourage you to read it, compare it to the stabs information on your
4220 system, and send improvements on the document in general (to
4221 bug-gdb@prep.ai.mit.edu).
4223 And, of course, many bugs have been fixed.
4226 *** Changes in GDB-4.6:
4228 * Better support for C++ function names
4230 GDB now accepts as input the "demangled form" of C++ overloaded function
4231 names and member function names, and can do command completion on such names
4232 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4233 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4234 Make use of command completion, it is your friend.
4236 GDB also now accepts a variety of C++ mangled symbol formats. They are
4237 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4238 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4239 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4240 for the list of formats.
4242 * G++ symbol mangling problem
4244 Recent versions of gcc have a bug in how they emit debugging information for
4245 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4246 directory) can be applied to gcc to fix the problem. Alternatively, if you
4247 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4248 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4249 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4252 * New 'maintenance' command
4254 All of the commands related to hacking GDB internals have been moved out of
4255 the main command set, and now live behind the 'maintenance' command. This
4256 can also be abbreviated as 'mt'. The following changes were made:
4258 dump-me -> maintenance dump-me
4259 info all-breakpoints -> maintenance info breakpoints
4260 printmsyms -> maintenance print msyms
4261 printobjfiles -> maintenance print objfiles
4262 printpsyms -> maintenance print psymbols
4263 printsyms -> maintenance print symbols
4265 The following commands are new:
4267 maintenance demangle Call internal GDB demangler routine to
4268 demangle a C++ link name and prints the result.
4269 maintenance print type Print a type chain for a given symbol
4271 * Change to .gdbinit file processing
4273 We now read the $HOME/.gdbinit file before processing the argv arguments
4274 (e.g. reading symbol files or core files). This allows global parameters to
4275 be set, which will apply during the symbol reading. The ./.gdbinit is still
4276 read after argv processing.
4278 * New hosts supported
4280 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4282 GNU/Linux support i386-unknown-linux or linux
4284 We are also including code to support the HP/PA running BSD and HPUX. This
4285 is almost guaranteed not to work, as we didn't have time to test or build it
4286 for this release. We are including it so that the more adventurous (or
4287 masochistic) of you can play with it. We also had major problems with the
4288 fact that the compiler that we got from HP doesn't support the -g option.
4291 * New targets supported
4293 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4295 * More smarts about finding #include files
4297 GDB now remembers the compilation directory for all include files, and for
4298 all files from which C is generated (like yacc and lex sources). This
4299 greatly improves GDB's ability to find yacc/lex sources, and include files,
4300 especially if you are debugging your program from a directory different from
4301 the one that contains your sources.
4303 We also fixed a bug which caused difficulty with listing and setting
4304 breakpoints in include files which contain C code. (In the past, you had to
4305 try twice in order to list an include file that you hadn't looked at before.)
4307 * Interesting infernals change
4309 GDB now deals with arbitrary numbers of sections, where the symbols for each
4310 section must be relocated relative to that section's landing place in the
4311 target's address space. This work was needed to support ELF with embedded
4312 stabs used by Solaris-2.0.
4314 * Bug fixes (of course!)
4316 There have been loads of fixes for the following things:
4317 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4318 i960, stabs, DOS(GO32), procfs, etc...
4320 See the ChangeLog for details.
4322 *** Changes in GDB-4.5:
4324 * New machines supported (host and target)
4326 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4328 SGI Irix-4.x mips-sgi-irix4 or iris4
4330 * New malloc package
4332 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4333 Mmalloc is capable of handling mutiple heaps of memory. It is also
4334 capable of saving a heap to a file, and then mapping it back in later.
4335 This can be used to greatly speedup the startup of GDB by using a
4336 pre-parsed symbol table which lives in a mmalloc managed heap. For
4337 more details, please read mmalloc/mmalloc.texi.
4341 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4342 'help info proc' for details.
4344 * MIPS ecoff symbol table format
4346 The code that reads MIPS symbol table format is now supported on all hosts.
4347 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4350 * File name changes for MS-DOS
4352 Many files in the config directories have been renamed to make it easier to
4353 support GDB on MS-DOSe systems (which have very restrictive file name
4354 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4355 environment) is close to working but has some remaining problems. Note
4356 that debugging of DOS programs is not supported, due to limitations
4357 in the ``operating system'', but it can be used to host cross-debugging.
4359 * Cross byte order fixes
4361 Many fixes have been made to support cross debugging of Sparc and MIPS
4362 targets from hosts whose byte order differs.
4364 * New -mapped and -readnow options
4366 If memory-mapped files are available on your system through the 'mmap'
4367 system call, you can use the -mapped option on the `file' or
4368 `symbol-file' commands to cause GDB to write the symbols from your
4369 program into a reusable file. If the program you are debugging is
4370 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4371 Future GDB debugging sessions will notice the presence of this file,
4372 and will quickly map in symbol information from it, rather than reading
4373 the symbol table from the executable program. Using the '-mapped'
4374 option in a GDB `file' or `symbol-file' command has the same effect as
4375 starting GDB with the '-mapped' command-line option.
4377 You can cause GDB to read the entire symbol table immediately by using
4378 the '-readnow' option with any of the commands that load symbol table
4379 information (or on the GDB command line). This makes the command
4380 slower, but makes future operations faster.
4382 The -mapped and -readnow options are typically combined in order to
4383 build a `fred.syms' file that contains complete symbol information.
4384 A simple GDB invocation to do nothing but build a `.syms' file for future
4387 gdb -batch -nx -mapped -readnow programname
4389 The `.syms' file is specific to the host machine on which GDB is run.
4390 It holds an exact image of GDB's internal symbol table. It cannot be
4391 shared across multiple host platforms.
4393 * longjmp() handling
4395 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4396 siglongjmp() without losing control. This feature has not yet been ported to
4397 all systems. It currently works on many 386 platforms, all MIPS-based
4398 platforms (SGI, DECstation, etc), and Sun3/4.
4402 Preliminary work has been put in to support the new Solaris OS from Sun. At
4403 this time, it can control and debug processes, but it is not capable of
4408 As always, many many bug fixes. The major areas were with g++, and mipsread.
4409 People using the MIPS-based platforms should experience fewer mysterious
4410 crashes and trashed symbol tables.
4412 *** Changes in GDB-4.4:
4414 * New machines supported (host and target)
4416 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4418 BSD Reno on Vax vax-dec-bsd
4419 Ultrix on Vax vax-dec-ultrix
4421 * New machines supported (target)
4423 AMD 29000 embedded, using EBMON a29k-none-none
4427 GDB continues to improve its handling of C++. `References' work better.
4428 The demangler has also been improved, and now deals with symbols mangled as
4429 per the Annotated C++ Reference Guide.
4431 GDB also now handles `stabs' symbol information embedded in MIPS
4432 `ecoff' symbol tables. Since the ecoff format was not easily
4433 extensible to handle new languages such as C++, this appeared to be a
4434 good way to put C++ debugging info into MIPS binaries. This option
4435 will be supported in the GNU C compiler, version 2, when it is
4438 * New features for SVR4
4440 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4441 shared libraries. Debugging dynamically linked programs should present
4442 only minor differences from debugging statically linked programs.
4444 The `info proc' command will print out information about any process
4445 on an SVR4 system (including the one you are debugging). At the moment,
4446 it prints the address mappings of the process.
4448 If you bring up GDB on another SVR4 system, please send mail to
4449 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4451 * Better dynamic linking support in SunOS
4453 Reading symbols from shared libraries which contain debugging symbols
4454 now works properly. However, there remain issues such as automatic
4455 skipping of `transfer vector' code during function calls, which
4456 make it harder to debug code in a shared library, than to debug the
4457 same code linked statically.
4461 GDB is now using the latest `getopt' routines from the FSF. This
4462 version accepts the -- prefix for options with long names. GDB will
4463 continue to accept the old forms (-option and +option) as well.
4464 Various single letter abbreviations for options have been explicity
4465 added to the option table so that they won't get overshadowed in the
4466 future by other options that begin with the same letter.
4470 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4471 Many assorted bugs have been handled. Many more remain to be handled.
4472 See the various ChangeLog files (primarily in gdb and bfd) for details.
4475 *** Changes in GDB-4.3:
4477 * New machines supported (host and target)
4479 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4480 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4481 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4483 * Almost SCO Unix support
4485 We had hoped to support:
4486 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4487 (except for core file support), but we discovered very late in the release
4488 that it has problems with process groups that render gdb unusable. Sorry
4489 about that. I encourage people to fix it and post the fixes.
4491 * Preliminary ELF and DWARF support
4493 GDB can read ELF object files on System V Release 4, and can handle
4494 debugging records for C, in DWARF format, in ELF files. This support
4495 is preliminary. If you bring up GDB on another SVR4 system, please
4496 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4501 GDB now uses the latest `readline' library. One user-visible change
4502 is that two tabs will list possible command completions, which previously
4503 required typing M-? (meta-question mark, or ESC ?).
4507 The `stepi' bug that many of you noticed has been squashed.
4508 Many bugs in C++ have been handled. Many more remain to be handled.
4509 See the various ChangeLog files (primarily in gdb and bfd) for details.
4511 * State of the MIPS world (in case you wondered):
4513 GDB can understand the symbol tables emitted by the compilers
4514 supplied by most vendors of MIPS-based machines, including DEC. These
4515 symbol tables are in a format that essentially nobody else uses.
4517 Some versions of gcc come with an assembler post-processor called
4518 mips-tfile. This program is required if you want to do source-level
4519 debugging of gcc-compiled programs. I believe FSF does not ship
4520 mips-tfile with gcc version 1, but it will eventually come with gcc
4523 Debugging of g++ output remains a problem. g++ version 1.xx does not
4524 really support it at all. (If you're lucky, you should be able to get
4525 line numbers and stack traces to work, but no parameters or local
4526 variables.) With some work it should be possible to improve the
4529 When gcc version 2 is released, you will have somewhat better luck.
4530 However, even then you will get confusing results for inheritance and
4533 We will eventually provide full debugging of g++ output on
4534 DECstations. This will probably involve some kind of stabs-in-ecoff
4535 encapulation, but the details have not been worked out yet.
4538 *** Changes in GDB-4.2:
4540 * Improved configuration
4542 Only one copy of `configure' exists now, and it is not self-modifying.
4543 Porting BFD is simpler.
4547 The `step' and `next' commands now only stop at the first instruction
4548 of a source line. This prevents the multiple stops that used to occur
4549 in switch statements, for-loops, etc. `Step' continues to stop if a
4550 function that has debugging information is called within the line.
4554 Lots of small bugs fixed. More remain.
4556 * New host supported (not target)
4558 Intel 386 PC clone running Mach i386-none-mach
4561 *** Changes in GDB-4.1:
4563 * Multiple source language support
4565 GDB now has internal scaffolding to handle several source languages.
4566 It determines the type of each source file from its filename extension,
4567 and will switch expression parsing and number formatting to match the
4568 language of the function in the currently selected stack frame.
4569 You can also specifically set the language to be used, with
4570 `set language c' or `set language modula-2'.
4574 GDB now has preliminary support for the GNU Modula-2 compiler,
4575 currently under development at the State University of New York at
4576 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4577 continue through the fall of 1991 and into 1992.
4579 Other Modula-2 compilers are currently not supported, and attempting to
4580 debug programs compiled with them will likely result in an error as the
4581 symbol table is read. Feel free to work on it, though!
4583 There are hooks in GDB for strict type checking and range checking,
4584 in the `Modula-2 philosophy', but they do not currently work.
4588 GDB can now write to executable and core files (e.g. patch
4589 a variable's value). You must turn this switch on, specify
4590 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4591 by assigning a new value to a variable. Modifications take
4594 * Automatic SunOS shared library reading
4596 When you run your program, GDB automatically determines where its
4597 shared libraries (if any) have been loaded, and reads their symbols.
4598 The `share' command is no longer needed. This also works when
4599 examining core files.
4603 You can specify the number of lines that the `list' command shows.
4606 * New machines supported (host and target)
4608 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4609 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4610 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4612 * New hosts supported (not targets)
4614 IBM RT/PC: romp-ibm-aix or rtpc
4616 * New targets supported (not hosts)
4618 AMD 29000 embedded with COFF a29k-none-coff
4619 AMD 29000 embedded with a.out a29k-none-aout
4620 Ultracomputer remote kernel debug a29k-nyu-kern
4622 * New remote interfaces
4628 *** Changes in GDB-4.0:
4632 Wide output is wrapped at good places to make the output more readable.
4634 Gdb now supports cross-debugging from a host machine of one type to a
4635 target machine of another type. Communication with the target system
4636 is over serial lines. The ``target'' command handles connecting to the
4637 remote system; the ``load'' command will download a program into the
4638 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4639 also supports debugging of realtime processes running under VxWorks,
4640 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4641 stub on the target system.
4643 New CPUs supported include the AMD 29000 and Intel 960.
4645 GDB now reads object files and symbol tables via a ``binary file''
4646 library, which allows a single copy of GDB to debug programs of multiple
4647 object file types such as a.out and coff.
4649 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4650 refcard.dvi and refcard.ps are available to format it).
4653 * Control-Variable user interface simplified
4655 All variables that control the operation of the debugger can be set
4656 by the ``set'' command, and displayed by the ``show'' command.
4658 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4659 ``Show prompt'' produces the response:
4660 Gdb's prompt is new-gdb=>.
4662 What follows are the NEW set commands. The command ``help set'' will
4663 print a complete list of old and new set commands. ``help set FOO''
4664 will give a longer description of the variable FOO. ``show'' will show
4665 all of the variable descriptions and their current settings.
4667 confirm on/off: Enables warning questions for operations that are
4668 hard to recover from, e.g. rerunning the program while
4669 it is already running. Default is ON.
4671 editing on/off: Enables EMACS style command line editing
4672 of input. Previous lines can be recalled with
4673 control-P, the current line can be edited with control-B,
4674 you can search for commands with control-R, etc.
4677 history filename NAME: NAME is where the gdb command history
4678 will be stored. The default is .gdb_history,
4679 or the value of the environment variable
4682 history size N: The size, in commands, of the command history. The
4683 default is 256, or the value of the environment variable
4686 history save on/off: If this value is set to ON, the history file will
4687 be saved after exiting gdb. If set to OFF, the
4688 file will not be saved. The default is OFF.
4690 history expansion on/off: If this value is set to ON, then csh-like
4691 history expansion will be performed on
4692 command line input. The default is OFF.
4694 radix N: Sets the default radix for input and output. It can be set
4695 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4696 in the current radix, so "set radix 10" is always a no-op.
4698 height N: This integer value is the number of lines on a page. Default
4699 is 24, the current `stty rows'' setting, or the ``li#''
4700 setting from the termcap entry matching the environment
4703 width N: This integer value is the number of characters on a line.
4704 Default is 80, the current `stty cols'' setting, or the ``co#''
4705 setting from the termcap entry matching the environment
4708 Note: ``set screensize'' is obsolete. Use ``set height'' and
4709 ``set width'' instead.
4711 print address on/off: Print memory addresses in various command displays,
4712 such as stack traces and structure values. Gdb looks
4713 more ``symbolic'' if you turn this off; it looks more
4714 ``machine level'' with it on. Default is ON.
4716 print array on/off: Prettyprint arrays. New convenient format! Default
4719 print demangle on/off: Print C++ symbols in "source" form if on,
4722 print asm-demangle on/off: Same, for assembler level printouts
4725 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4728 * Support for Epoch Environment.
4730 The epoch environment is a version of Emacs v18 with windowing. One
4731 new command, ``inspect'', is identical to ``print'', except that if you
4732 are running in the epoch environment, the value is printed in its own
4736 * Support for Shared Libraries
4738 GDB can now debug programs and core files that use SunOS shared libraries.
4739 Symbols from a shared library cannot be referenced
4740 before the shared library has been linked with the program (this
4741 happens after you type ``run'' and before the function main() is entered).
4742 At any time after this linking (including when examining core files
4743 from dynamically linked programs), gdb reads the symbols from each
4744 shared library when you type the ``sharedlibrary'' command.
4745 It can be abbreviated ``share''.
4747 sharedlibrary REGEXP: Load shared object library symbols for files
4748 matching a unix regular expression. No argument
4749 indicates to load symbols for all shared libraries.
4751 info sharedlibrary: Status of loaded shared libraries.
4756 A watchpoint stops execution of a program whenever the value of an
4757 expression changes. Checking for this slows down execution
4758 tremendously whenever you are in the scope of the expression, but is
4759 quite useful for catching tough ``bit-spreader'' or pointer misuse
4760 problems. Some machines such as the 386 have hardware for doing this
4761 more quickly, and future versions of gdb will use this hardware.
4763 watch EXP: Set a watchpoint (breakpoint) for an expression.
4765 info watchpoints: Information about your watchpoints.
4767 delete N: Deletes watchpoint number N (same as breakpoints).
4768 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4769 enable N: Re-enables watchpoint number N (same as breakpoints).
4772 * C++ multiple inheritance
4774 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4777 * C++ exception handling
4779 Gdb now supports limited C++ exception handling. Besides the existing
4780 ability to breakpoint on an exception handler, gdb can breakpoint on
4781 the raising of an exception (before the stack is peeled back to the
4784 catch FOO: If there is a FOO exception handler in the dynamic scope,
4785 set a breakpoint to catch exceptions which may be raised there.
4786 Multiple exceptions (``catch foo bar baz'') may be caught.
4788 info catch: Lists all exceptions which may be caught in the
4789 current stack frame.
4792 * Minor command changes
4794 The command ``call func (arg, arg, ...)'' now acts like the print
4795 command, except it does not print or save a value if the function's result
4796 is void. This is similar to dbx usage.
4798 The ``up'' and ``down'' commands now always print the frame they end up
4799 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4800 frames without printing.
4802 * New directory command
4804 'dir' now adds directories to the FRONT of the source search path.
4805 The path starts off empty. Source files that contain debug information
4806 about the directory in which they were compiled can be found even
4807 with an empty path; Sun CC and GCC include this information. If GDB can't
4808 find your source file in the current directory, type "dir .".
4810 * Configuring GDB for compilation
4812 For normal use, type ``./configure host''. See README or gdb.texinfo
4815 GDB now handles cross debugging. If you are remotely debugging between
4816 two different machines, type ``./configure host -target=targ''.
4817 Host is the machine where GDB will run; targ is the machine
4818 where the program that you are debugging will run.