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 * GDBserver now supports stdio connections.
14 E.g. (gdb) target remote | ssh myhost gdbserver - hello
16 * The binary "gdbtui" can no longer be built or installed.
17 Use "gdb -tui" instead.
19 * GDB will now print "flag" enums specially. A flag enum is one where
20 all the enumerator values have no bits in common when pairwise
21 "and"ed. When printing a value whose type is a flag enum, GDB will
22 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
23 (gdb) print (enum E) 3
26 * The filename part of a linespec will now match trailing components
27 of a source file name. For example, "break gcc/expr.c:1000" will
28 now set a breakpoint in build/gcc/expr.c, but not
31 * The "info proc" and "generate-core-file" commands will now also
32 work on remote targets connected to GDBserver on Linux.
34 * The command "info catch" has been removed. It has been disabled
39 ** "catch load" and "catch unload" can be used to stop when a shared
40 library is loaded or unloaded, respectively.
42 *** Changes in GDB 7.4
44 * GDB now handles ambiguous linespecs more consistently; the existing
45 FILE:LINE support has been expanded to other types of linespecs. A
46 breakpoint will now be set on all matching locations in all
47 inferiors, and locations will be added or removed according to
50 * GDB now allows you to skip uninteresting functions and files when
51 stepping with the "skip function" and "skip file" commands.
53 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
54 and "show remote hardware-watchpoint-length-limit". These allows to
55 set or show the maximum length limit (in bytes) of a remote
56 target hardware watchpoint.
58 This allows e.g. to use "unlimited" hardware watchpoints with the
59 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
60 watchpoints are slower than real hardware watchpoints but are
61 significantly faster than gdb software watchpoints.
65 ** The register_pretty_printer function in module gdb.printing now takes
66 an optional `replace' argument. If True, the new printer replaces any
69 ** The "maint set python print-stack on|off" command has been
70 deprecated and will be deleted in GDB 7.5.
71 A new command: "set python print-stack none|full|message" has
72 replaced it. Additionally, the default for "print-stack" is
73 now "message", which just prints the error message without
76 ** A prompt substitution hook (prompt_hook) is now available to the
79 ** A new Python module, gdb.prompt has been added to the GDB Python
80 modules library. This module provides functionality for
81 escape sequences in prompts (used by set/show
82 extended-prompt). These escape sequences are replaced by their
85 ** Python commands and convenience-functions located in
86 'data-directory'/python/gdb/command and
87 'data-directory'/python/gdb/function are now automatically loaded
90 ** Blocks now provide four new attributes. global_block and
91 static_block will return the global and static blocks
92 respectively. is_static and is_global are boolean attributes
93 that indicate if the block is one of those two types.
95 ** Symbols now provide the "type" attribute, the type of the symbol.
97 ** The "gdb.breakpoint" function has been deprecated in favor of
100 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
101 of a function. This class is based on the "finish" command
102 available in the CLI.
104 ** Type objects for struct and union types now allow access to
105 the fields using standard Python dictionary (mapping) methods.
106 For example, "some_type['myfield']" now works, as does
109 ** A new event "gdb.new_objfile" has been added, triggered by loading a
112 ** A new function, "deep_items" has been added to the gdb.types
113 module in the GDB Python modules library. This function returns
114 an iterator over the fields of a struct or union type. Unlike
115 the standard Python "iteritems" method, it will recursively traverse
116 any anonymous fields.
120 ** "*stopped" events can report several new "reason"s, such as
123 ** Breakpoint changes are now notified using new async records, like
124 "=breakpoint-modified".
126 ** New command -ada-task-info.
128 * libthread-db-search-path now supports two special values: $sdir and $pdir.
129 $sdir specifies the default system locations of shared libraries.
130 $pdir specifies the directory where the libpthread used by the application
133 GDB no longer looks in $sdir and $pdir after it has searched the directories
134 mentioned in libthread-db-search-path. If you want to search those
135 directories, they must be specified in libthread-db-search-path.
136 The default value of libthread-db-search-path on GNU/Linux and Solaris
137 systems is now "$sdir:$pdir".
139 $pdir is not supported by gdbserver, it is currently ignored.
140 $sdir is supported by gdbserver.
142 * New configure option --with-iconv-bin.
143 When using the internationalization support like the one in the GNU C
144 library, GDB will invoke the "iconv" program to get a list of supported
145 character sets. If this program lives in a non-standard location, one can
146 use this option to specify where to find it.
148 * When natively debugging programs on PowerPC BookE processors running
149 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
150 watchpoints, which specify a mask in addition to an address to watch.
151 The mask specifies that some bits of an address (the bits which are
152 reset in the mask) should be ignored when matching the address accessed
153 by the inferior against the watchpoint address. See the "PowerPC Embedded"
154 section in the user manual for more details.
156 * The new option --once causes GDBserver to stop listening for connections once
157 the first connection is made. The listening port used by GDBserver will
158 become available after that.
160 * New commands "info macros" and "alias" have been added.
162 * New function parameters suffix @entry specifies value of function parameter
163 at the time the function got called. Entry values are available only since
169 "!" is now an alias of the "shell" command.
170 Note that no space is needed between "!" and SHELL COMMAND.
174 watch EXPRESSION mask MASK_VALUE
175 The watch command now supports the mask argument which allows creation
176 of masked watchpoints, if the current architecture supports this feature.
178 info auto-load-scripts [REGEXP]
179 This command was formerly named "maintenance print section-scripts".
180 It is now generally useful and is no longer a maintenance-only command.
182 info macro [-all] [--] MACRO
183 The info macro command has new options `-all' and `--'. The first for
184 printing all definitions of a macro. The second for explicitly specifying
185 the end of arguments and the beginning of the macro name in case the macro
186 name starts with a hyphen.
188 collect[/s] EXPRESSIONS
189 The tracepoint collect command now takes an optional modifier "/s"
190 that directs it to dereference pointer-to-character types and
191 collect the bytes of memory up to a zero byte. The behavior is
192 similar to what you see when you use the regular print command on a
193 string. An optional integer following the "/s" sets a bound on the
194 number of bytes that will be collected.
197 The trace start command now interprets any supplied arguments as a
198 note to be recorded with the trace run, with an effect similar to
199 setting the variable trace-notes.
202 The trace stop command now interprets any arguments as a note to be
203 mentioned along with the tstatus report that the trace was stopped
204 with a command. The effect is similar to setting the variable
207 * Tracepoints can now be enabled and disabled at any time after a trace
208 experiment has been started using the standard "enable" and "disable"
209 commands. It is now possible to start a trace experiment with no enabled
210 tracepoints; GDB will display a warning, but will allow the experiment to
211 begin, assuming that tracepoints will be enabled as needed while the trace
214 * Fast tracepoints on 32-bit x86-architectures can now be placed at
215 locations with 4-byte instructions, when they were previously
216 limited to locations with instructions of 5 bytes or longer.
222 Set the GDB prompt, and allow escape sequences to be inserted to
223 display miscellaneous information (see 'help set extended-prompt'
224 for the list of sequences). This prompt (and any information
225 accessed through the escape sequences) is updated every time the
228 set print entry-values (both|compact|default|if-needed|no|only|preferred)
229 show print entry-values
230 Set printing of frame argument values at function entry. In some cases
231 GDB can determine the value of function argument which was passed by the
232 function caller, even if the value was modified inside the called function.
234 set debug entry-values
235 show debug entry-values
236 Control display of debugging info for determining frame argument values at
237 function entry and virtual tail call frames.
239 set basenames-may-differ
240 show basenames-may-differ
241 Set whether a source file may have multiple base names.
242 (A "base name" is the name of a file with the directory part removed.
243 Example: The base name of "/home/user/hello.c" is "hello.c".)
244 If set, GDB will canonicalize file names (e.g., expand symlinks)
245 before comparing them. Canonicalization is an expensive operation,
246 but it allows the same file be known by more than one base name.
247 If not set (the default), all source files are assumed to have just
248 one base name, and gdb will do file name comparisons more efficiently.
254 Set a user name and notes for the current and any future trace runs.
255 This is useful for long-running and/or disconnected traces, to
256 inform others (or yourself) as to who is running the trace, supply
257 contact information, or otherwise explain what is going on.
260 show trace-stop-notes
261 Set a note attached to the trace run, that is displayed when the
262 trace has been stopped by a tstop command. This is useful for
263 instance as an explanation, if you are stopping a trace run that was
264 started by someone else.
270 Dynamically enable a tracepoint in a started trace experiment.
274 Dynamically disable a tracepoint in a started trace experiment.
278 Set the user and notes of the trace run.
282 Query the current status of a tracepoint.
286 Query the minimum length of instruction at which a fast tracepoint may
289 * Dcache size (number of lines) and line-size are now runtime-configurable
290 via "set dcache line" and "set dcache line-size" commands.
294 Texas Instruments TMS320C6x tic6x-*-*
298 Renesas RL78 rl78-*-elf
300 *** Changes in GDB 7.3.1
302 * The build failure for NetBSD and OpenBSD targets have now been fixed.
304 *** Changes in GDB 7.3
306 * GDB has a new command: "thread find [REGEXP]".
307 It finds the thread id whose name, target id, or thread extra info
308 matches the given regular expression.
310 * The "catch syscall" command now works on mips*-linux* targets.
312 * The -data-disassemble MI command now supports modes 2 and 3 for
313 dumping the instruction opcodes.
315 * New command line options
317 -data-directory DIR Specify DIR as the "data-directory".
318 This is mostly for testing purposes.
320 * The "maint set python auto-load on|off" command has been renamed to
321 "set auto-load-scripts on|off".
323 * GDB has a new command: "set directories".
324 It is like the "dir" command except that it replaces the
325 source path list instead of augmenting it.
327 * GDB now understands thread names.
329 On GNU/Linux, "info threads" will display the thread name as set by
330 prctl or pthread_setname_np.
332 There is also a new command, "thread name", which can be used to
333 assign a name internally for GDB to display.
336 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
337 has been integrated into GDB.
341 ** The function gdb.Write now accepts an optional keyword 'stream'.
342 This keyword, when provided, will direct the output to either
343 stdout, stderr, or GDB's logging output.
345 ** Parameters can now be be sub-classed in Python, and in particular
346 you may implement the get_set_doc and get_show_doc functions.
347 This improves how Parameter set/show documentation is processed
348 and allows for more dynamic content.
350 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
351 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
352 have an is_valid method.
354 ** Breakpoints can now be sub-classed in Python, and in particular
355 you may implement a 'stop' function that is executed each time
356 the inferior reaches that breakpoint.
358 ** New function gdb.lookup_global_symbol looks up a global symbol.
360 ** GDB values in Python are now callable if the value represents a
361 function. For example, if 'some_value' represents a function that
362 takes two integer parameters and returns a value, you can call
363 that function like so:
365 result = some_value (10,20)
367 ** Module gdb.types has been added.
368 It contains a collection of utilities for working with gdb.Types objects:
369 get_basic_type, has_field, make_enum_dict.
371 ** Module gdb.printing has been added.
372 It contains utilities for writing and registering pretty-printers.
373 New classes: PrettyPrinter, SubPrettyPrinter,
374 RegexpCollectionPrettyPrinter.
375 New function: register_pretty_printer.
377 ** New commands "info pretty-printers", "enable pretty-printer" and
378 "disable pretty-printer" have been added.
380 ** gdb.parameter("directories") is now available.
382 ** New function gdb.newest_frame returns the newest frame in the
385 ** The gdb.InferiorThread class has a new "name" attribute. This
386 holds the thread's name.
388 ** Python Support for Inferior events.
389 Python scripts can add observers to be notified of events
390 occurring in the process being debugged.
391 The following events are currently supported:
392 - gdb.events.cont Continue event.
393 - gdb.events.exited Inferior exited event.
394 - gdb.events.stop Signal received, and Breakpoint hit events.
398 ** GDB now puts template parameters in scope when debugging in an
399 instantiation. For example, if you have:
401 template<int X> int func (void) { return X; }
403 then if you step into func<5>, "print X" will show "5". This
404 feature requires proper debuginfo support from the compiler; it
405 was added to GCC 4.5.
407 ** The motion commands "next", "finish", "until", and "advance" now
408 work better when exceptions are thrown. In particular, GDB will
409 no longer lose control of the inferior; instead, the GDB will
410 stop the inferior at the point at which the exception is caught.
411 This functionality requires a change in the exception handling
412 code that was introduced in GCC 4.5.
414 * GDB now follows GCC's rules on accessing volatile objects when
415 reading or writing target state during expression evaluation.
416 One notable difference to prior behavior is that "print x = 0"
417 no longer generates a read of x; the value of the assignment is
418 now always taken directly from the value being assigned.
420 * GDB now has some support for using labels in the program's source in
421 linespecs. For instance, you can use "advance label" to continue
422 execution to a label.
424 * GDB now has support for reading and writing a new .gdb_index
425 section. This section holds a fast index of DWARF debugging
426 information and can be used to greatly speed up GDB startup and
427 operation. See the documentation for `save gdb-index' for details.
429 * The "watch" command now accepts an optional "-location" argument.
430 When used, this causes GDB to watch the memory referred to by the
431 expression. Such a watchpoint is never deleted due to it going out
434 * GDB now supports thread debugging of core dumps on GNU/Linux.
436 GDB now activates thread debugging using the libthread_db library
437 when debugging GNU/Linux core dumps, similarly to when debugging
438 live processes. As a result, when debugging a core dump file, GDB
439 is now able to display pthread_t ids of threads. For example, "info
440 threads" shows the same output as when debugging the process when it
441 was live. In earlier releases, you'd see something like this:
444 * 1 LWP 6780 main () at main.c:10
446 While now you see this:
449 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
451 It is also now possible to inspect TLS variables when debugging core
454 When debugging a core dump generated on a machine other than the one
455 used to run GDB, you may need to point GDB at the correct
456 libthread_db library with the "set libthread-db-search-path"
457 command. See the user manual for more details on this command.
459 * When natively debugging programs on PowerPC BookE processors running
460 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
461 which stop execution of the inferior whenever it executes an instruction
462 at any address within the specified range. See the "PowerPC Embedded"
463 section in the user manual for more details.
465 * New features in the GDB remote stub, GDBserver
467 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
468 and i686 LynxOS (version 5.x).
470 ** GDBserver is now supported on Blackfin Linux.
472 * New native configurations
474 ia64 HP-UX ia64-*-hpux*
478 Analog Devices, Inc. Blackfin Processor bfin-*
480 * Ada task switching is now supported on sparc-elf targets when
481 debugging a program using the Ravenscar Profile. For more information,
482 see the "Tasking Support when using the Ravenscar Profile" section
483 in the GDB user manual.
485 * Guile support was removed.
487 * New features in the GNU simulator
489 ** The --map-info flag lists all known core mappings.
491 ** CFI flashes may be simulated via the "cfi" device.
493 *** Changes in GDB 7.2
495 * Shared library support for remote targets by default
497 When GDB is configured for a generic, non-OS specific target, like
498 for example, --target=arm-eabi or one of the many *-*-elf targets,
499 GDB now queries remote stubs for loaded shared libraries using the
500 `qXfer:libraries:read' packet. Previously, shared library support
501 was always disabled for such configurations.
505 ** Argument Dependent Lookup (ADL)
507 In C++ ADL lookup directs function search to the namespaces of its
508 arguments even if the namespace has not been imported.
518 Here the compiler will search for `foo' in the namespace of 'b'
519 and find A::foo. GDB now supports this. This construct is commonly
520 used in the Standard Template Library for operators.
522 ** Improved User Defined Operator Support
524 In addition to member operators, GDB now supports lookup of operators
525 defined in a namespace and imported with a `using' directive, operators
526 defined in the global scope, operators imported implicitly from an
527 anonymous namespace, and the ADL operators mentioned in the previous
529 GDB now also supports proper overload resolution for all the previously
530 mentioned flavors of operators.
532 ** static const class members
534 Printing of static const class members that are initialized in the
535 class definition has been fixed.
537 * Windows Thread Information Block access.
539 On Windows targets, GDB now supports displaying the Windows Thread
540 Information Block (TIB) structure. This structure is visible either
541 by using the new command `info w32 thread-information-block' or, by
542 dereferencing the new convenience variable named `$_tlb', a
543 thread-specific pointer to the TIB. This feature is also supported
544 when remote debugging using GDBserver.
548 Static tracepoints are calls in the user program into a tracing
549 library. One such library is a port of the LTTng kernel tracer to
550 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
551 When debugging with GDBserver, GDB now supports combining the GDB
552 tracepoint machinery with such libraries. For example: the user can
553 use GDB to probe a static tracepoint marker (a call from the user
554 program into the tracing library) with the new "strace" command (see
555 "New commands" below). This creates a "static tracepoint" in the
556 breakpoint list, that can be manipulated with the same feature set
557 as fast and regular tracepoints. E.g., collect registers, local and
558 global variables, collect trace state variables, and define
559 tracepoint conditions. In addition, the user can collect extra
560 static tracepoint marker specific data, by collecting the new
561 $_sdata internal variable. When analyzing the trace buffer, you can
562 inspect $_sdata like any other variable available to GDB. For more
563 information, see the "Tracepoints" chapter in GDB user manual. New
564 remote packets have been defined to support static tracepoints, see
565 the "New remote packets" section below.
567 * Better reconstruction of tracepoints after disconnected tracing
569 GDB will attempt to download the original source form of tracepoint
570 definitions when starting a trace run, and then will upload these
571 upon reconnection to the target, resulting in a more accurate
572 reconstruction of the tracepoints that are in use on the target.
576 You can now exercise direct control over the ways that GDB can
577 affect your program. For instance, you can disallow the setting of
578 breakpoints, so that the program can run continuously (assuming
579 non-stop mode). In addition, the "observer" variable is available
580 to switch all of the different controls; in observer mode, GDB
581 cannot affect the target's behavior at all, which is useful for
582 tasks like diagnosing live systems in the field.
584 * The new convenience variable $_thread holds the number of the
591 Return the address of the Windows Thread Information Block of a given thread.
595 In response to several of the tracepoint packets, the target may now
596 also respond with a number of intermediate `qRelocInsn' request
597 packets before the final result packet, to have GDB handle
598 relocating an instruction to execute at a different address. This
599 is particularly useful for stubs that support fast tracepoints. GDB
600 reports support for this feature in the qSupported packet.
604 List static tracepoint markers in the target program.
608 List static tracepoint markers at a given address in the target
611 qXfer:statictrace:read
613 Read the static trace data collected (by a `collect $_sdata'
614 tracepoint action). The remote stub reports support for this packet
615 to gdb's qSupported query.
619 Send the current settings of GDB's permission flags.
623 Send part of the source (textual) form of a tracepoint definition,
624 which includes location, conditional, and action list.
626 * The source command now accepts a -s option to force searching for the
627 script in the source search path even if the script name specifies
630 * New features in the GDB remote stub, GDBserver
632 - GDBserver now support tracepoints (including fast tracepoints, and
633 static tracepoints). The feature is currently supported by the
634 i386-linux and amd64-linux builds. See the "Tracepoints support
635 in gdbserver" section in the manual for more information.
637 GDBserver JIT compiles the tracepoint's conditional agent
638 expression bytecode into native code whenever possible for low
639 overhead dynamic tracepoints conditionals. For such tracepoints,
640 an expression that examines program state is evaluated when the
641 tracepoint is reached, in order to determine whether to capture
642 trace data. If the condition is simple and false, processing the
643 tracepoint finishes very quickly and no data is gathered.
645 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
646 for static tracepoints support.
648 - GDBserver now supports x86_64 Windows 64-bit debugging.
650 * GDB now sends xmlRegisters= in qSupported packet to indicate that
651 it understands register description.
653 * The --batch flag now disables pagination and queries.
655 * X86 general purpose registers
657 GDB now supports reading/writing byte, word and double-word x86
658 general purpose registers directly. This means you can use, say,
659 $ah or $ax to refer, respectively, to the byte register AH and
660 16-bit word register AX that are actually portions of the 32-bit
661 register EAX or 64-bit register RAX.
663 * The `commands' command now accepts a range of breakpoints to modify.
664 A plain `commands' following a command that creates multiple
665 breakpoints affects all the breakpoints set by that command. This
666 applies to breakpoints set by `rbreak', and also applies when a
667 single `break' command creates multiple breakpoints (e.g.,
668 breakpoints on overloaded c++ functions).
670 * The `rbreak' command now accepts a filename specification as part of
671 its argument, limiting the functions selected by the regex to those
672 in the specified file.
674 * Support for remote debugging Windows and SymbianOS shared libraries
675 from Unix hosts has been improved. Non Windows GDB builds now can
676 understand target reported file names that follow MS-DOS based file
677 system semantics, such as file names that include drive letters and
678 use the backslash character as directory separator. This makes it
679 possible to transparently use the "set sysroot" and "set
680 solib-search-path" on Unix hosts to point as host copies of the
681 target's shared libraries. See the new command "set
682 target-file-system-kind" described below, and the "Commands to
683 specify files" section in the user manual for more information.
687 eval template, expressions...
688 Convert the values of one or more expressions under the control
689 of the string template to a command line, and call it.
691 set target-file-system-kind unix|dos-based|auto
692 show target-file-system-kind
693 Set or show the assumed file system kind for target reported file
696 save breakpoints <filename>
697 Save all current breakpoint definitions to a file suitable for use
698 in a later debugging session. To read the saved breakpoint
699 definitions, use the `source' command.
701 `save tracepoints' is a new alias for `save-tracepoints'. The latter
704 info static-tracepoint-markers
705 Display information about static tracepoint markers in the target.
707 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
708 Define a static tracepoint by probing a marker at the given
709 function, line, address, or marker ID.
713 Enable and disable observer mode.
715 set may-write-registers on|off
716 set may-write-memory on|off
717 set may-insert-breakpoints on|off
718 set may-insert-tracepoints on|off
719 set may-insert-fast-tracepoints on|off
720 set may-interrupt on|off
721 Set individual permissions for GDB effects on the target. Note that
722 some of these settings can have undesirable or surprising
723 consequences, particularly when changed in the middle of a session.
724 For instance, disabling the writing of memory can prevent
725 breakpoints from being inserted, cause single-stepping to fail, or
726 even crash your program, if you disable after breakpoints have been
727 inserted. However, GDB should not crash.
729 set record memory-query on|off
730 show record memory-query
731 Control whether to stop the inferior if memory changes caused
732 by an instruction cannot be recorded.
737 The disassemble command now supports "start,+length" form of two arguments.
741 ** GDB now provides a new directory location, called the python directory,
742 where Python scripts written for GDB can be installed. The location
743 of that directory is <data-directory>/python, where <data-directory>
744 is the GDB data directory. For more details, see section `Scripting
745 GDB using Python' in the manual.
747 ** The GDB Python API now has access to breakpoints, symbols, symbol
748 tables, program spaces, inferiors, threads and frame's code blocks.
749 Additionally, GDB Parameters can now be created from the API, and
750 manipulated via set/show in the CLI.
752 ** New functions gdb.target_charset, gdb.target_wide_charset,
753 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
755 ** New exception gdb.GdbError.
757 ** Pretty-printers are now also looked up in the current program space.
759 ** Pretty-printers can now be individually enabled and disabled.
761 ** GDB now looks for names of Python scripts to auto-load in a
762 special section named `.debug_gdb_scripts', in addition to looking
763 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
765 * Tracepoint actions were unified with breakpoint commands. In particular,
766 there are no longer differences in "info break" output for breakpoints and
767 tracepoints and the "commands" command can be used for both tracepoints and
772 ARM Symbian arm*-*-symbianelf*
774 * D language support.
775 GDB now supports debugging programs written in the D programming
778 * GDB now supports the extended ptrace interface for PowerPC which is
779 available since Linux kernel version 2.6.34. This automatically enables
780 any hardware breakpoints and additional hardware watchpoints available in
781 the processor. The old ptrace interface exposes just one hardware
782 watchpoint and no hardware breakpoints.
784 * GDB is now able to use the Data Value Compare (DVC) register available on
785 embedded PowerPC processors to implement in hardware simple watchpoint
786 conditions of the form:
788 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
790 This works in native GDB running on Linux kernels with the extended ptrace
791 interface mentioned above.
793 *** Changes in GDB 7.1
799 GDB now supports importing of namespaces in C++. This enables the
800 user to inspect variables from imported namespaces. Support for
801 namepace aliasing has also been added. So, if a namespace is
802 aliased in the current scope (e.g. namepace C=A; ) the user can
803 print variables using the alias (e.g. (gdb) print C::x).
807 All known bugs relating to the printing of virtual base class were
808 fixed. It is now possible to call overloaded static methods using a
813 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
814 and reinterpret_cast<> are now handled by the C++ expression parser.
818 Xilinx MicroBlaze microblaze-*-*
823 Xilinx MicroBlaze microblaze
826 * Multi-program debugging.
828 GDB now has support for multi-program (a.k.a. multi-executable or
829 multi-exec) debugging. This allows for debugging multiple inferiors
830 simultaneously each running a different program under the same GDB
831 session. See "Debugging Multiple Inferiors and Programs" in the
832 manual for more information. This implied some user visible changes
833 in the multi-inferior support. For example, "info inferiors" now
834 lists inferiors that are not running yet or that have exited
835 already. See also "New commands" and "New options" below.
837 * New tracing features
839 GDB's tracepoint facility now includes several new features:
841 ** Trace state variables
843 GDB tracepoints now include support for trace state variables, which
844 are variables managed by the target agent during a tracing
845 experiment. They are useful for tracepoints that trigger each
846 other, so for instance one tracepoint can count hits in a variable,
847 and then a second tracepoint has a condition that is true when the
848 count reaches a particular value. Trace state variables share the
849 $-syntax of GDB convenience variables, and can appear in both
850 tracepoint actions and condition expressions. Use the "tvariable"
851 command to create, and "info tvariables" to view; see "Trace State
852 Variables" in the manual for more detail.
856 GDB now includes an option for defining fast tracepoints, which
857 targets may implement more efficiently, such as by installing a jump
858 into the target agent rather than a trap instruction. The resulting
859 speedup can be by two orders of magnitude or more, although the
860 tradeoff is that some program locations on some target architectures
861 might not allow fast tracepoint installation, for instance if the
862 instruction to be replaced is shorter than the jump. To request a
863 fast tracepoint, use the "ftrace" command, with syntax identical to
864 the regular trace command.
866 ** Disconnected tracing
868 It is now possible to detach GDB from the target while it is running
869 a trace experiment, then reconnect later to see how the experiment
870 is going. In addition, a new variable disconnected-tracing lets you
871 tell the target agent whether to continue running a trace if the
872 connection is lost unexpectedly.
876 GDB now has the ability to save the trace buffer into a file, and
877 then use that file as a target, similarly to you can do with
878 corefiles. You can select trace frames, print data that was
879 collected in them, and use tstatus to display the state of the
880 tracing run at the moment that it was saved. To create a trace
881 file, use "tsave <filename>", and to use it, do "target tfile
884 ** Circular trace buffer
886 You can ask the target agent to handle the trace buffer as a
887 circular buffer, discarding the oldest trace frames to make room for
888 newer ones, by setting circular-trace-buffer to on. This feature may
889 not be available for all target agents.
894 The disassemble command, when invoked with two arguments, now requires
895 the arguments to be comma-separated.
898 The info variables command now displays variable definitions. Files
899 which only declare a variable are not shown.
902 The source command is now capable of sourcing Python scripts.
903 This feature is dependent on the debugger being build with Python
906 Related to this enhancement is also the introduction of a new command
907 "set script-extension" (see below).
909 * New commands (for set/show, see "New options" below)
911 record save [<FILENAME>]
912 Save a file (in core file format) containing the process record
913 execution log for replay debugging at a later time.
915 record restore <FILENAME>
916 Restore the process record execution log that was saved at an
917 earlier time, for replay debugging.
919 add-inferior [-copies <N>] [-exec <FILENAME>]
922 clone-inferior [-copies <N>] [ID]
923 Make a new inferior ready to execute the same program another
929 maint info program-spaces
930 List the program spaces loaded into GDB.
932 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
933 show remote interrupt-sequence
934 Allow the user to select one of ^C, a BREAK signal or BREAK-g
935 as the sequence to the remote target in order to interrupt the execution.
936 Ctrl-C is a default. Some system prefers BREAK which is high level of
937 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
938 Magic SysRq g. It is BREAK signal and character 'g'.
940 set remote interrupt-on-connect [on | off]
941 show remote interrupt-on-connect
942 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
943 remote target when gdb connects to it. This is needed when you debug
946 set remotebreak [on | off]
948 Deprecated. Use "set/show remote interrupt-sequence" instead.
950 tvariable $NAME [ = EXP ]
951 Create or modify a trace state variable.
954 List trace state variables and their values.
956 delete tvariable $NAME ...
957 Delete one or more trace state variables.
960 Evaluate the given expressions without collecting anything into the
961 trace buffer. (Valid in tracepoint actions only.)
963 ftrace FN / FILE:LINE / *ADDR
964 Define a fast tracepoint at the given function, line, or address.
966 * New expression syntax
968 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
969 GDB now parses 0b101010 identically with 42.
973 set follow-exec-mode new|same
974 show follow-exec-mode
975 Control whether GDB reuses the same inferior across an exec call or
976 creates a new one. This is useful to be able to restart the old
977 executable after the inferior having done an exec call.
979 set default-collect EXPR, ...
981 Define a list of expressions to be collected at each tracepoint.
982 This is a useful way to ensure essential items are not overlooked,
983 such as registers or a critical global variable.
985 set disconnected-tracing
986 show disconnected-tracing
987 If set to 1, the target is instructed to continue tracing if it
988 loses its connection to GDB. If 0, the target is to stop tracing
991 set circular-trace-buffer
992 show circular-trace-buffer
993 If set to on, the target is instructed to use a circular trace buffer
994 and discard the oldest trace frames instead of stopping the trace due
995 to a full trace buffer. If set to off, the trace stops when the buffer
996 fills up. Some targets may not support this.
998 set script-extension off|soft|strict
999 show script-extension
1000 If set to "off", the debugger does not perform any script language
1001 recognition, and all sourced files are assumed to be GDB scripts.
1002 If set to "soft" (the default), files are sourced according to
1003 filename extension, falling back to GDB scripts if the first
1005 If set to "strict", files are sourced according to filename extension.
1007 set ada trust-PAD-over-XVS on|off
1008 show ada trust-PAD-over-XVS
1009 If off, activate a workaround against a bug in the debugging information
1010 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1011 the GCC sources for more information about the GNAT encoding and
1012 PAD types in particular). It is always safe to set this option to
1013 off, but this introduces a slight performance penalty. The default
1016 * Python API Improvements
1018 ** GDB provides the new class gdb.LazyString. This is useful in
1019 some pretty-printing cases. The new method gdb.Value.lazy_string
1020 provides a simple way to create objects of this type.
1022 ** The fields returned by gdb.Type.fields now have an
1023 `is_base_class' attribute.
1025 ** The new method gdb.Type.range returns the range of an array type.
1027 ** The new method gdb.parse_and_eval can be used to parse and
1028 evaluate an expression.
1030 * New remote packets
1033 Define a trace state variable.
1036 Get the current value of a trace state variable.
1039 Set desired tracing behavior upon disconnection.
1042 Set the trace buffer to be linear or circular.
1045 Get data about the tracepoints currently in use.
1049 Process record now works correctly with hardware watchpoints.
1051 Multiple bug fixes have been made to the mips-irix port, making it
1052 much more reliable. In particular:
1053 - Debugging threaded applications is now possible again. Previously,
1054 GDB would hang while starting the program, or while waiting for
1055 the program to stop at a breakpoint.
1056 - Attaching to a running process no longer hangs.
1057 - An error occurring while loading a core file has been fixed.
1058 - Changing the value of the PC register now works again. This fixes
1059 problems observed when using the "jump" command, or when calling
1060 a function from GDB, or even when assigning a new value to $pc.
1061 - With the "finish" and "return" commands, the return value for functions
1062 returning a small array is now correctly printed.
1063 - It is now possible to break on shared library code which gets executed
1064 during a shared library init phase (code executed while executing
1065 their .init section). Previously, the breakpoint would have no effect.
1066 - GDB is now able to backtrace through the signal handler for
1067 non-threaded programs.
1069 PIE (Position Independent Executable) programs debugging is now supported.
1070 This includes debugging execution of PIC (Position Independent Code) shared
1071 libraries although for that, it should be possible to run such libraries as an
1074 *** Changes in GDB 7.0
1076 * GDB now has an interface for JIT compilation. Applications that
1077 dynamically generate code can create symbol files in memory and register
1078 them with GDB. For users, the feature should work transparently, and
1079 for JIT developers, the interface is documented in the GDB manual in the
1080 "JIT Compilation Interface" chapter.
1082 * Tracepoints may now be conditional. The syntax is as for
1083 breakpoints; either an "if" clause appended to the "trace" command,
1084 or the "condition" command is available. GDB sends the condition to
1085 the target for evaluation using the same bytecode format as is used
1086 for tracepoint actions.
1088 * The disassemble command now supports: an optional /r modifier, print the
1089 raw instructions in hex as well as in symbolic form, and an optional /m
1090 modifier to print mixed source+assembly.
1092 * Process record and replay
1094 In a architecture environment that supports ``process record and
1095 replay'', ``process record and replay'' target can record a log of
1096 the process execution, and replay it with both forward and reverse
1099 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1100 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1101 set execution-direction {forward|reverse}, for targets that support
1104 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1105 feature is available with a native GDB running on kernel version
1108 * GDB now has support for multi-byte and wide character sets on the
1109 target. Strings whose character type is wchar_t, char16_t, or
1110 char32_t are now correctly printed. GDB supports wide- and unicode-
1111 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1112 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1113 `printf'. This feature requires iconv to work properly; if your
1114 system does not have a working iconv, GDB can use GNU libiconv. See
1115 the installation instructions for more information.
1117 * GDB now supports automatic retrieval of shared library files from
1118 remote targets. To use this feature, specify a system root that begins
1119 with the `remote:' prefix, either via the `set sysroot' command or via
1120 the `--with-sysroot' configure-time option.
1122 * "info sharedlibrary" now takes an optional regex of libraries to show,
1123 and it now reports if a shared library has no debugging information.
1125 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1126 now complete on file names.
1128 * When completing in expressions, gdb will attempt to limit
1129 completions to allowable structure or union fields, where appropriate.
1130 For instance, consider:
1132 # struct example { int f1; double f2; };
1133 # struct example variable;
1136 If the user types TAB at the end of this command line, the available
1137 completions will be "f1" and "f2".
1139 * Inlined functions are now supported. They show up in backtraces, and
1140 the "step", "next", and "finish" commands handle them automatically.
1142 * GDB now supports the token-splicing (##) and stringification (#)
1143 operators when expanding macros. It also supports variable-arity
1146 * GDB now supports inspecting extra signal information, exported by
1147 the new $_siginfo convenience variable. The feature is currently
1148 implemented on linux ARM, i386 and amd64.
1150 * GDB can now display the VFP floating point registers and NEON vector
1151 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1152 can provide these registers (requires Linux 2.6.30 or later). Remote
1153 and simulator targets may also provide them.
1155 * New remote packets
1158 Search memory for a sequence of bytes.
1161 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1162 operation over reliable transport links. Use of this packet is
1163 controlled by the `set remote noack-packet' command.
1166 Kill the process with the specified process ID. Use this in preference
1167 to `k' when multiprocess protocol extensions are supported.
1170 Obtains additional operating system information
1174 Read or write additional signal information.
1176 * Removed remote protocol undocumented extension
1178 An undocumented extension to the remote protocol's `S' stop reply
1179 packet that permited the stub to pass a process id was removed.
1180 Remote servers should use the `T' stop reply packet instead.
1182 * GDB now supports multiple function calling conventions according to the
1183 DWARF-2 DW_AT_calling_convention function attribute.
1185 * The SH target utilizes the aforementioned change to distinguish between gcc
1186 and Renesas calling convention. It also adds the new CLI commands
1187 `set/show sh calling-convention'.
1189 * GDB can now read compressed debug sections, as produced by GNU gold
1190 with the --compress-debug-sections=zlib flag.
1192 * 64-bit core files are now supported on AIX.
1194 * Thread switching is now supported on Tru64.
1196 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1197 which will be allocated using malloc later in program execution.
1199 * The qXfer:libraries:read remote procotol packet now allows passing a
1200 list of section offsets.
1202 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1203 conditions handling signals delivered during attach or thread creation
1204 have also been fixed.
1206 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1207 From the user's standpoint, all unqualified instances of True and False
1208 are treated as the standard definitions, regardless of context.
1210 * GDB now parses C++ symbol and type names more flexibly. For
1213 template<typename T> class C { };
1216 GDB will now correctly handle all of:
1218 ptype C<char const *>
1219 ptype C<char const*>
1220 ptype C<const char *>
1221 ptype C<const char*>
1223 * New features in the GDB remote stub, gdbserver
1225 - The "--wrapper" command-line argument tells gdbserver to use a
1226 wrapper program to launch programs for debugging.
1228 - On PowerPC and S/390 targets, it is now possible to use a single
1229 gdbserver executable to debug both 32-bit and 64-bit programs.
1230 (This requires gdbserver itself to be built as a 64-bit executable.)
1232 - gdbserver uses the new noack protocol mode for TCP connections to
1233 reduce communications latency, if also supported and enabled in GDB.
1235 - Support for the sparc64-linux-gnu target is now included in
1238 - The amd64-linux build of gdbserver now supports debugging both
1239 32-bit and 64-bit programs.
1241 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1242 now support hardware watchpoints, and will use them automatically
1247 GDB now has support for scripting using Python. Whether this is
1248 available is determined at configure time.
1250 New GDB commands can now be written in Python.
1252 * Ada tasking support
1254 Ada tasks can now be inspected in GDB. The following commands have
1258 Print the list of Ada tasks.
1260 Print detailed information about task number N.
1262 Print the task number of the current task.
1264 Switch the context of debugging to task number N.
1266 * Support for user-defined prefixed commands. The "define" command can
1267 add new commands to existing prefixes, e.g. "target".
1269 * Multi-inferior, multi-process debugging.
1271 GDB now has generalized support for multi-inferior debugging. See
1272 "Debugging Multiple Inferiors" in the manual for more information.
1273 Although availability still depends on target support, the command
1274 set is more uniform now. The GNU/Linux specific multi-forks support
1275 has been migrated to this new framework. This implied some user
1276 visible changes; see "New commands" and also "Removed commands"
1279 * Target descriptions can now describe the target OS ABI. See the
1280 "Target Description Format" section in the user manual for more
1283 * Target descriptions can now describe "compatible" architectures
1284 to indicate that the target can execute applications for a different
1285 architecture in addition to those for the main target architecture.
1286 See the "Target Description Format" section in the user manual for
1289 * Multi-architecture debugging.
1291 GDB now includes general supports for debugging applications on
1292 hybrid systems that use more than one single processor architecture
1293 at the same time. Each such hybrid architecture still requires
1294 specific support to be added. The only hybrid architecture supported
1295 in this version of GDB is the Cell Broadband Engine.
1297 * GDB now supports integrated debugging of Cell/B.E. applications that
1298 use both the PPU and SPU architectures. To enable support for hybrid
1299 Cell/B.E. debugging, you need to configure GDB to support both the
1300 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1301 --enable-targets configure option.
1303 * Non-stop mode debugging.
1305 For some targets, GDB now supports an optional mode of operation in
1306 which you can examine stopped threads while other threads continue
1307 to execute freely. This is referred to as non-stop mode, with the
1308 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1309 section in the user manual for more information.
1311 To be able to support remote non-stop debugging, a remote stub needs
1312 to implement the non-stop mode remote protocol extensions, as
1313 described in the "Remote Non-Stop" section of the user manual. The
1314 GDB remote stub, gdbserver, has been adjusted to support these
1315 extensions on linux targets.
1317 * New commands (for set/show, see "New options" below)
1319 catch syscall [NAME(S) | NUMBER(S)]
1320 Catch system calls. Arguments, which should be names of system
1321 calls or their numbers, mean catch only those syscalls. Without
1322 arguments, every syscall will be caught. When the inferior issues
1323 any of the specified syscalls, GDB will stop and announce the system
1324 call, both when it is called and when its call returns. This
1325 feature is currently available with a native GDB running on the
1326 Linux Kernel, under the following architectures: x86, x86_64,
1327 PowerPC and PowerPC64.
1329 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1331 Search memory for a sequence of bytes.
1333 maint set python print-stack
1334 maint show python print-stack
1335 Show a stack trace when an error is encountered in a Python script.
1338 Invoke CODE by passing it to the Python interpreter.
1343 These allow macros to be defined, undefined, and listed
1347 Show operating system information about processes.
1350 List the inferiors currently under GDB's control.
1353 Switch focus to inferior number NUM.
1356 Detach from inferior number NUM.
1359 Kill inferior number NUM.
1363 set spu stop-on-load
1364 show spu stop-on-load
1365 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1367 set spu auto-flush-cache
1368 show spu auto-flush-cache
1369 Control whether to automatically flush the software-managed cache
1370 during Cell/B.E. debugging.
1372 set sh calling-convention
1373 show sh calling-convention
1374 Control the calling convention used when calling SH target functions.
1377 show debug timestamp
1378 Control display of timestamps with GDB debugging output.
1380 set disassemble-next-line
1381 show disassemble-next-line
1382 Control display of disassembled source lines or instructions when
1385 set remote noack-packet
1386 show remote noack-packet
1387 Set/show the use of remote protocol QStartNoAckMode packet. See above
1388 under "New remote packets."
1390 set remote query-attached-packet
1391 show remote query-attached-packet
1392 Control use of remote protocol `qAttached' (query-attached) packet.
1394 set remote read-siginfo-object
1395 show remote read-siginfo-object
1396 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1399 set remote write-siginfo-object
1400 show remote write-siginfo-object
1401 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1404 set remote reverse-continue
1405 show remote reverse-continue
1406 Control use of remote protocol 'bc' (reverse-continue) packet.
1408 set remote reverse-step
1409 show remote reverse-step
1410 Control use of remote protocol 'bs' (reverse-step) packet.
1412 set displaced-stepping
1413 show displaced-stepping
1414 Control displaced stepping mode. Displaced stepping is a way to
1415 single-step over breakpoints without removing them from the debuggee.
1416 Also known as "out-of-line single-stepping".
1419 show debug displaced
1420 Control display of debugging info for displaced stepping.
1422 maint set internal-error
1423 maint show internal-error
1424 Control what GDB does when an internal error is detected.
1426 maint set internal-warning
1427 maint show internal-warning
1428 Control what GDB does when an internal warning is detected.
1433 Use a wrapper program to launch programs for debugging.
1435 set multiple-symbols (all|ask|cancel)
1436 show multiple-symbols
1437 The value of this variable can be changed to adjust the debugger behavior
1438 when an expression or a breakpoint location contains an ambiguous symbol
1439 name (an overloaded function name, for instance).
1441 set breakpoint always-inserted
1442 show breakpoint always-inserted
1443 Keep breakpoints always inserted in the target, as opposed to inserting
1444 them when resuming the target, and removing them when the target stops.
1445 This option can improve debugger performance on slow remote targets.
1447 set arm fallback-mode (arm|thumb|auto)
1448 show arm fallback-mode
1449 set arm force-mode (arm|thumb|auto)
1451 These commands control how ARM GDB determines whether instructions
1452 are ARM or Thumb. The default for both settings is auto, which uses
1453 the current CPSR value for instructions without symbols; previous
1454 versions of GDB behaved as if "set arm fallback-mode arm".
1456 set disable-randomization
1457 show disable-randomization
1458 Standalone programs run with the virtual address space randomization enabled
1459 by default on some platforms. This option keeps the addresses stable across
1460 multiple debugging sessions.
1464 Control whether other threads are stopped or not when some thread hits
1469 Requests that asynchronous execution is enabled in the target, if available.
1470 In this case, it's possible to resume target in the background, and interact
1471 with GDB while the target is running. "show target-async" displays the
1472 current state of asynchronous execution of the target.
1474 set target-wide-charset
1475 show target-wide-charset
1476 The target-wide-charset is the name of the character set that GDB
1477 uses when printing characters whose type is wchar_t.
1479 set tcp auto-retry (on|off)
1481 set tcp connect-timeout
1482 show tcp connect-timeout
1483 These commands allow GDB to retry failed TCP connections to a remote stub
1484 with a specified timeout period; this is useful if the stub is launched
1485 in parallel with GDB but may not be ready to accept connections immediately.
1487 set libthread-db-search-path
1488 show libthread-db-search-path
1489 Control list of directories which GDB will search for appropriate
1492 set schedule-multiple (on|off)
1493 show schedule-multiple
1494 Allow GDB to resume all threads of all processes or only threads of
1495 the current process.
1499 Use more aggressive caching for accesses to the stack. This improves
1500 performance of remote debugging (particularly backtraces) without
1501 affecting correctness.
1503 set interactive-mode (on|off|auto)
1504 show interactive-mode
1505 Control whether GDB runs in interactive mode (on) or not (off).
1506 When in interactive mode, GDB waits for the user to answer all
1507 queries. Otherwise, GDB does not wait and assumes the default
1508 answer. When set to auto (the default), GDB determines which
1509 mode to use based on the stdin settings.
1514 For program forks, this is replaced by the new more generic `info
1515 inferiors' command. To list checkpoints, you can still use the
1516 `info checkpoints' command, which was an alias for the `info forks'
1520 Replaced by the new `inferior' command. To switch between
1521 checkpoints, you can still use the `restart' command, which was an
1522 alias for the `fork' command.
1525 This is removed, since some targets don't have a notion of
1526 processes. To switch between processes, you can still use the
1527 `inferior' command using GDB's own inferior number.
1530 For program forks, this is replaced by the new more generic `kill
1531 inferior' command. To delete a checkpoint, you can still use the
1532 `delete checkpoint' command, which was an alias for the `delete
1536 For program forks, this is replaced by the new more generic `detach
1537 inferior' command. To detach a checkpoint, you can still use the
1538 `detach checkpoint' command, which was an alias for the `detach
1541 * New native configurations
1543 x86/x86_64 Darwin i[34567]86-*-darwin*
1545 x86_64 MinGW x86_64-*-mingw*
1549 Lattice Mico32 lm32-*
1550 x86 DICOS i[34567]86-*-dicos*
1551 x86_64 DICOS x86_64-*-dicos*
1554 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1555 (mingw32ce) debugging.
1561 These commands were actually not implemented on any target.
1563 *** Changes in GDB 6.8
1565 * New native configurations
1567 NetBSD/hppa hppa*-*netbsd*
1568 Xtensa GNU/Linux xtensa*-*-linux*
1572 NetBSD/hppa hppa*-*-netbsd*
1573 Xtensa GNU/Lunux xtensa*-*-linux*
1575 * Change in command line behavior -- corefiles vs. process ids.
1577 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1578 attaching to process NUMBER fails, GDB no longer attempts to open a
1579 core file named NUMBER. Attaching to a program using the -c option
1580 is no longer supported. Instead, use the '-p' or '--pid' options.
1582 * GDB can now be built as a native debugger for debugging Windows x86
1583 (mingw32) Portable Executable (PE) programs.
1585 * Pending breakpoints no longer change their number when their address
1588 * GDB now supports breakpoints with multiple locations,
1589 including breakpoints on C++ constructors, inside C++ templates,
1590 and in inlined functions.
1592 * GDB's ability to debug optimized code has been improved. GDB more
1593 accurately identifies function bodies and lexical blocks that occupy
1594 more than one contiguous range of addresses.
1596 * Target descriptions can now describe registers for PowerPC.
1598 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1599 registers on PowerPC targets.
1601 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1602 targets even when the libthread_db library is not available.
1604 * The GDB remote stub, gdbserver, now supports the new file transfer
1605 commands (remote put, remote get, and remote delete).
1607 * The GDB remote stub, gdbserver, now supports run and attach in
1608 extended-remote mode.
1610 * hppa*64*-*-hpux11* target broken
1611 The debugger is unable to start a program and fails with the following
1612 error: "Error trying to get information about dynamic linker".
1613 The gdb-6.7 release is also affected.
1615 * GDB now supports the --enable-targets= configure option to allow
1616 building a single GDB executable that supports multiple remote
1617 target architectures.
1619 * GDB now supports debugging C and C++ programs which use the
1620 Decimal Floating Point extension. In addition, the PowerPC target
1621 now has a set of pseudo-registers to inspect decimal float values
1622 stored in two consecutive float registers.
1624 * The -break-insert MI command can optionally create pending
1627 * Improved support for debugging Ada
1628 Many improvements to the Ada language support have been made. These
1630 - Better support for Ada2005 interface types
1631 - Improved handling of arrays and slices in general
1632 - Better support for Taft-amendment types
1633 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1635 - Improved command completion in Ada
1638 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1643 set print frame-arguments (all|scalars|none)
1644 show print frame-arguments
1645 The value of this variable can be changed to control which argument
1646 values should be printed by the debugger when displaying a frame.
1651 Transfer files to and from a remote target, and delete remote files.
1658 Transfer files to and from a remote target, and delete remote files.
1660 * New remote packets
1667 Open, close, read, write, and delete files on the remote system.
1670 Attach to an existing process on the remote system, in extended-remote
1674 Run a new process on the remote system, in extended-remote mode.
1676 *** Changes in GDB 6.7
1678 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1679 bfd, libiberty and opcodes, as revealed by static analysis donated by
1680 Coverity, Inc. (http://scan.coverity.com).
1682 * When looking up multiply-defined global symbols, GDB will now prefer the
1683 symbol definition in the current shared library if it was built using the
1684 -Bsymbolic linker option.
1686 * When the Text User Interface (TUI) is not configured, GDB will now
1687 recognize the -tui command-line option and print a message that the TUI
1690 * The GDB remote stub, gdbserver, now has lower overhead for high
1691 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1693 * GDB for MIPS targets now autodetects whether a remote target provides
1694 32-bit or 64-bit register values.
1696 * Support for C++ member pointers has been improved.
1698 * GDB now understands XML target descriptions, which specify the
1699 target's overall architecture. GDB can read a description from
1700 a local file or over the remote serial protocol.
1702 * Vectors of single-byte data use a new integer type which is not
1703 automatically displayed as character or string data.
1705 * The /s format now works with the print command. It displays
1706 arrays of single-byte integers and pointers to single-byte integers
1709 * Target descriptions can now describe target-specific registers,
1710 for architectures which have implemented the support (currently
1711 only ARM, M68K, and MIPS).
1713 * GDB and the GDB remote stub, gdbserver, now support the XScale
1716 * The GDB remote stub, gdbserver, has been updated to support
1717 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1718 has been rewritten to use the standard GDB remote protocol.
1720 * GDB can now step into C++ functions which are called through thunks.
1722 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1724 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1725 layout. It also supports a TextSeg= and DataSeg= response when only
1726 segment base addresses (rather than offsets) are available.
1728 * The /i format now outputs any trailing branch delay slot instructions
1729 immediately following the last instruction within the count specified.
1731 * The GDB remote protocol "T" stop reply packet now supports a
1732 "library" response. Combined with the new "qXfer:libraries:read"
1733 packet, this response allows GDB to debug shared libraries on targets
1734 where the operating system manages the list of loaded libraries (e.g.
1735 Windows and SymbianOS).
1737 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1738 (DLLs) on Windows and Windows CE targets.
1740 * GDB now supports a faster verification that a .debug file matches its binary
1741 according to its build-id signature, if the signature is present.
1747 Enable or disable hardware flow control (RTS/CTS) on the serial port
1748 when debugging using remote targets.
1750 set mem inaccessible-by-default
1751 show mem inaccessible-by-default
1752 If the target supplies a memory map, for instance via the remote
1753 protocol's "qXfer:memory-map:read" packet, setting this variable
1754 prevents GDB from accessing memory outside the memory map. This
1755 is useful for targets with memory mapped registers or which react
1756 badly to accesses of unmapped address space.
1758 set breakpoint auto-hw
1759 show breakpoint auto-hw
1760 If the target supplies a memory map, for instance via the remote
1761 protocol's "qXfer:memory-map:read" packet, setting this variable
1762 lets GDB use hardware breakpoints automatically for memory regions
1763 where it can not use software breakpoints. This covers both the
1764 "break" command and internal breakpoints used for other commands
1765 including "next" and "finish".
1768 catch exception unhandled
1769 Stop the program execution when Ada exceptions are raised.
1772 Stop the program execution when an Ada assertion failed.
1776 Set an alternate system root for target files. This is a more
1777 general version of "set solib-absolute-prefix", which is now
1778 an alias to "set sysroot".
1781 Provide extended SPU facility status information. This set of
1782 commands is available only when debugging the Cell/B.E. SPU
1785 * New native configurations
1787 OpenBSD/sh sh*-*openbsd*
1790 unset tdesc filename
1792 Use the specified local file as an XML target description, and do
1793 not query the target for its built-in description.
1797 OpenBSD/sh sh*-*-openbsd*
1798 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1799 Toshiba Media Processor mep-elf
1801 * New remote packets
1804 Ignore the specified signals; pass them directly to the debugged program
1805 without stopping other threads or reporting them to GDB.
1807 qXfer:features:read:
1808 Read an XML target description from the target, which describes its
1813 Read or write contents of an spufs file on the target system. These
1814 packets are available only on the Cell/B.E. SPU architecture.
1816 qXfer:libraries:read:
1817 Report the loaded shared libraries. Combined with new "T" packet
1818 response, this packet allows GDB to debug shared libraries on
1819 targets where the operating system manages the list of loaded
1820 libraries (e.g. Windows and SymbianOS).
1824 Support for these obsolete configurations has been removed.
1832 i[34567]86-*-lynxos*
1833 i[34567]86-*-netware*
1834 i[34567]86-*-sco3.2v5*
1835 i[34567]86-*-sco3.2v4*
1837 i[34567]86-*-sysv4.2*
1840 i[34567]86-*-unixware2*
1841 i[34567]86-*-unixware*
1850 * Other removed features
1857 Various m68k-only ROM monitors.
1864 Various Renesas ROM monitors and debugging interfaces for SH and
1869 Support for a Macraigor serial interface to on-chip debugging.
1870 GDB does not directly support the newer parallel or USB
1875 A debug information format. The predecessor to DWARF 2 and
1876 DWARF 3, which are still supported.
1878 Support for the HP aCC compiler on HP-UX/PA-RISC
1880 SOM-encapsulated symbolic debugging information, automatic
1881 invocation of pxdb, and the aCC custom C++ ABI. This does not
1882 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1883 with aCC can still be debugged on an assembly level.
1885 MIPS ".pdr" sections
1887 A MIPS-specific format used to describe stack frame layout
1888 in debugging information.
1892 GDB could work with an older version of Guile to debug
1893 the interpreter and Scheme programs running in it.
1895 set mips stack-arg-size
1896 set mips saved-gpreg-size
1898 Use "set mips abi" to control parameter passing for MIPS.
1900 *** Changes in GDB 6.6
1905 Cell Broadband Engine SPU spu-elf
1907 * GDB can now be configured as a cross-debugger targeting native Windows
1908 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1909 running on a Windows system over TCP/IP to debug Windows programs.
1911 * The GDB remote stub, gdbserver, has been updated to support Windows and
1912 Cygwin debugging. Both single-threaded and multi-threaded programs are
1915 * The "set trust-readonly-sections" command works again. This command was
1916 broken in GDB 6.3, 6.4, and 6.5.
1918 * The "load" command now supports writing to flash memory, if the remote
1919 stub provides the required support.
1921 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1922 longer requires symbolic debug information (e.g. DWARF-2).
1927 unset substitute-path
1928 show substitute-path
1929 Manage a list of substitution rules that GDB uses to rewrite the name
1930 of the directories where the sources are located. This can be useful
1931 for instance when the sources were moved to a different location
1932 between compilation and debugging.
1936 Print each CLI command as it is executed. Each command is prefixed with
1937 a number of `+' symbols representing the nesting depth.
1938 The source command now has a `-v' option to enable the same feature.
1942 The ARM Demon monitor support (RDP protocol, "target rdp").
1944 Kernel Object Display, an embedded debugging feature which only worked with
1945 an obsolete version of Cisco IOS.
1947 The 'set download-write-size' and 'show download-write-size' commands.
1949 * New remote packets
1952 Tell a stub about GDB client features, and request remote target features.
1953 The first feature implemented is PacketSize, which allows the target to
1954 specify the size of packets it can handle - to minimize the number of
1955 packets required and improve performance when connected to a remote
1959 Fetch an OS auxilliary vector from the remote stub. This packet is a
1960 more efficient replacement for qPart:auxv:read.
1962 qXfer:memory-map:read:
1963 Fetch a memory map from the remote stub, including information about
1964 RAM, ROM, and flash memory devices.
1969 Erase and program a flash memory device.
1971 * Removed remote packets
1974 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1975 used it, and only gdbserver implemented it.
1977 *** Changes in GDB 6.5
1981 Renesas M32C/M16C m32c-elf
1983 Morpho Technologies ms1 ms1-elf
1987 init-if-undefined Initialize a convenience variable, but
1988 only if it doesn't already have a value.
1990 The following commands are presently only implemented for native GNU/Linux:
1992 checkpoint Save a snapshot of the program state.
1994 restart <n> Return the program state to a
1995 previously saved state.
1997 info checkpoints List currently saved checkpoints.
1999 delete-checkpoint <n> Delete a previously saved checkpoint.
2001 set|show detach-on-fork Tell gdb whether to detach from a newly
2002 forked process, or to keep debugging it.
2004 info forks List forks of the user program that
2005 are available to be debugged.
2007 fork <n> Switch to debugging one of several
2008 forks of the user program that are
2009 available to be debugged.
2011 delete-fork <n> Delete a fork from the list of forks
2012 that are available to be debugged (and
2013 kill the forked process).
2015 detach-fork <n> Delete a fork from the list of forks
2016 that are available to be debugged (and
2017 allow the process to continue).
2021 Morpho Technologies ms2 ms1-elf
2023 * Improved Windows host support
2025 GDB now builds as a cross debugger hosted on i686-mingw32, including
2026 native console support, and remote communications using either
2027 network sockets or serial ports.
2029 * Improved Modula-2 language support
2031 GDB can now print most types in the Modula-2 syntax. This includes:
2032 basic types, set types, record types, enumerated types, range types,
2033 pointer types and ARRAY types. Procedure var parameters are correctly
2034 printed and hexadecimal addresses and character constants are also
2035 written in the Modula-2 syntax. Best results can be obtained by using
2036 GNU Modula-2 together with the -gdwarf-2 command line option.
2040 The ARM rdi-share module.
2042 The Netware NLM debug server.
2044 *** Changes in GDB 6.4
2046 * New native configurations
2048 OpenBSD/arm arm*-*-openbsd*
2049 OpenBSD/mips64 mips64-*-openbsd*
2053 Morpho Technologies ms1 ms1-elf
2055 * New command line options
2057 --batch-silent As for --batch, but totally silent.
2058 --return-child-result The debugger will exist with the same value
2059 the child (debugged) program exited with.
2060 --eval-command COMMAND, -ex COMMAND
2061 Execute a single GDB CLI command. This may be
2062 specified multiple times and in conjunction
2063 with the --command (-x) option.
2065 * Deprecated commands removed
2067 The following commands, that were deprecated in 2000, have been
2071 set|show arm disassembly-flavor set|show arm disassembler
2072 othernames set arm disassembler
2073 set|show remotedebug set|show debug remote
2074 set|show archdebug set|show debug arch
2075 set|show eventdebug set|show debug event
2078 * New BSD user-level threads support
2080 It is now possible to debug programs using the user-level threads
2081 library on OpenBSD and FreeBSD. Currently supported (target)
2084 FreeBSD/amd64 x86_64-*-freebsd*
2085 FreeBSD/i386 i386-*-freebsd*
2086 OpenBSD/i386 i386-*-openbsd*
2088 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2089 are not yet supported.
2091 * New support for Matsushita MN10300 w/sim added
2092 (Work in progress). mn10300-elf.
2094 * REMOVED configurations and files
2096 VxWorks and the XDR protocol *-*-vxworks
2097 Motorola MCORE mcore-*-*
2098 National Semiconductor NS32000 ns32k-*-*
2100 * New "set print array-indexes" command
2102 After turning this setting "on", GDB prints the index of each element
2103 when displaying arrays. The default is "off" to preserve the previous
2106 * VAX floating point support
2108 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2110 * User-defined command support
2112 In addition to using $arg0..$arg9 for argument passing, it is now possible
2113 to use $argc to determine now many arguments have been passed. See the
2114 section on user-defined commands in the user manual for more information.
2116 *** Changes in GDB 6.3:
2118 * New command line option
2120 GDB now accepts -l followed by a number to set the timeout for remote
2123 * GDB works with GCC -feliminate-dwarf2-dups
2125 GDB now supports a more compact representation of DWARF-2 debug
2126 information using DW_FORM_ref_addr references. These are produced
2127 by GCC with the option -feliminate-dwarf2-dups and also by some
2128 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2129 to use -feliminate-dwarf2-dups.
2131 * Internationalization
2133 When supported by the host system, GDB will be built with
2134 internationalization (libintl). The task of marking up the sources is
2135 continued, we're looking forward to our first translation.
2139 Initial support for debugging programs compiled with the GNAT
2140 implementation of the Ada programming language has been integrated
2141 into GDB. In this release, support is limited to expression evaluation.
2143 * New native configurations
2145 GNU/Linux/m32r m32r-*-linux-gnu
2149 GDB's remote protocol now includes support for the 'p' packet. This
2150 packet is used to fetch individual registers from a remote inferior.
2152 * END-OF-LIFE registers[] compatibility module
2154 GDB's internal register infrastructure has been completely rewritten.
2155 The new infrastructure making possible the implementation of key new
2156 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2159 GDB 6.3 will be the last release to include the the registers[]
2160 compatibility module that allowed out-of-date configurations to
2161 continue to work. This change directly impacts the following
2171 powerpc bdm protocol
2173 Unless there is activity to revive these configurations, they will be
2174 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2176 * OBSOLETE configurations and files
2178 Configurations that have been declared obsolete in this release have
2179 been commented out. Unless there is activity to revive these
2180 configurations, the next release of GDB will have their sources
2181 permanently REMOVED.
2190 *** Changes in GDB 6.2.1:
2192 * MIPS `break main; run' gave an heuristic-fence-post warning
2194 When attempting to run even a simple program, a warning about
2195 heuristic-fence-post being hit would be reported. This problem has
2198 * MIPS IRIX 'long double' crashed GDB
2200 When examining a long double variable, GDB would get a segmentation
2201 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2202 IRIX long double values).
2206 A bug in the VAX stack code was causing problems with the "next"
2207 command. This problem has been fixed.
2209 *** Changes in GDB 6.2:
2211 * Fix for ``many threads''
2213 On GNU/Linux systems that use the NPTL threads library, a program
2214 rapidly creating and deleting threads would confuse GDB leading to the
2217 ptrace: No such process.
2218 thread_db_get_info: cannot get thread info: generic error
2220 This problem has been fixed.
2222 * "-async" and "-noasync" options removed.
2224 Support for the broken "-noasync" option has been removed (it caused
2227 * New ``start'' command.
2229 This command runs the program until the begining of the main procedure.
2231 * New BSD Kernel Data Access Library (libkvm) interface
2233 Using ``target kvm'' it is now possible to debug kernel core dumps and
2234 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2235 platforms. Currently supported (native-only) configurations are:
2237 FreeBSD/amd64 x86_64-*-freebsd*
2238 FreeBSD/i386 i?86-*-freebsd*
2239 NetBSD/i386 i?86-*-netbsd*
2240 NetBSD/m68k m68*-*-netbsd*
2241 NetBSD/sparc sparc-*-netbsd*
2242 OpenBSD/amd64 x86_64-*-openbsd*
2243 OpenBSD/i386 i?86-*-openbsd*
2244 OpenBSD/m68k m68*-openbsd*
2245 OpenBSD/sparc sparc-*-openbsd*
2247 * Signal trampoline code overhauled
2249 Many generic problems with GDB's signal handling code have been fixed.
2250 These include: backtraces through non-contiguous stacks; recognition
2251 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2252 call; backtrace through a signal trampoline; step into and out of
2253 signal handlers; and single-stepping in the signal trampoline.
2255 Please note that kernel bugs are a limiting factor here. These
2256 features have been shown to work on an s390 GNU/Linux system that
2257 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2259 * Cygwin support for DWARF 2 added.
2261 * New native configurations
2263 GNU/Linux/hppa hppa*-*-linux*
2264 OpenBSD/hppa hppa*-*-openbsd*
2265 OpenBSD/m68k m68*-*-openbsd*
2266 OpenBSD/m88k m88*-*-openbsd*
2267 OpenBSD/powerpc powerpc-*-openbsd*
2268 NetBSD/vax vax-*-netbsd*
2269 OpenBSD/vax vax-*-openbsd*
2271 * END-OF-LIFE frame compatibility module
2273 GDB's internal frame infrastructure has been completely rewritten.
2274 The new infrastructure making it possible to support key new features
2275 including DWARF 2 Call Frame Information. To aid in the task of
2276 migrating old configurations to this new infrastructure, a
2277 compatibility module, that allowed old configurations to continue to
2278 work, was also included.
2280 GDB 6.2 will be the last release to include this frame compatibility
2281 module. This change directly impacts the following configurations:
2291 Unless there is activity to revive these configurations, they will be
2292 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2294 * REMOVED configurations and files
2296 Sun 3, running SunOS 3 m68*-*-sunos3*
2297 Sun 3, running SunOS 4 m68*-*-sunos4*
2298 Sun 2, running SunOS 3 m68000-*-sunos3*
2299 Sun 2, running SunOS 4 m68000-*-sunos4*
2300 Motorola 680x0 running LynxOS m68*-*-lynxos*
2301 AT&T 3b1/Unix pc m68*-att-*
2302 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2303 decstation mips-dec-* mips-little-*
2304 riscos mips-*-riscos* mips-*-sysv*
2305 sonymips mips-sony-*
2306 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2308 *** Changes in GDB 6.1.1:
2310 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2312 The TUI (Text-mode User Interface) is now built as part of a default
2313 GDB configuration. It is enabled by either selecting the TUI with the
2314 command line option "-i=tui" or by running the separate "gdbtui"
2315 program. For more information on the TUI, see the manual "Debugging
2318 * Pending breakpoint support (also included in GDB 6.1)
2320 Support has been added to allow you to specify breakpoints in shared
2321 libraries that have not yet been loaded. If a breakpoint location
2322 cannot be found, and the "breakpoint pending" option is set to auto,
2323 GDB queries you if you wish to make the breakpoint pending on a future
2324 shared-library load. If and when GDB resolves the breakpoint symbol,
2325 the pending breakpoint is removed as one or more regular breakpoints
2328 Pending breakpoints are very useful for GCJ Java debugging.
2330 * Fixed ISO-C build problems
2332 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2333 non ISO-C code that stopped them being built using a more strict ISO-C
2334 compiler (e.g., IBM's C compiler).
2336 * Fixed build problem on IRIX 5
2338 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2339 wasn't able to compile compile on an IRIX 5 system.
2341 * Added execute permission to gdb/gdbserver/configure
2343 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2344 permission. This bug would cause configure to fail on a number of
2345 systems (Solaris, IRIX). Ref: server/519.
2347 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2349 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2350 has been updated to use constant array sizes.
2352 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2354 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2355 its generated DWARF Call Frame Info. This encoding was causing GDB to
2356 panic, that panic has been fixed. Ref: gdb/1628.
2358 * Fixed a problem when examining parameters in shared library code.
2360 When examining parameters in optimized shared library code generated
2361 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2362 not available''. GDB now correctly displays the variable's value.
2364 *** Changes in GDB 6.1:
2366 * Removed --with-mmalloc
2368 Support for the mmalloc memory manager has been removed, as it
2369 conflicted with the internal gdb byte cache.
2371 * Changes in AMD64 configurations
2373 The AMD64 target now includes the %cs and %ss registers. As a result
2374 the AMD64 remote protocol has changed; this affects the floating-point
2375 and SSE registers. If you rely on those registers for your debugging,
2376 you should upgrade gdbserver on the remote side.
2378 * Revised SPARC target
2380 The SPARC target has been completely revised, incorporating the
2381 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2382 support for LynxOS and SunOS 4 has been dropped. Calling functions
2383 from within GDB on operating systems with a non-executable stack
2384 (Solaris, OpenBSD) now works.
2388 GDB has a new C++ demangler which does a better job on the mangled
2389 names generated by current versions of g++. It also runs faster, so
2390 with this and other changes gdb should now start faster on large C++
2393 * DWARF 2 Location Expressions
2395 GDB support for location expressions has been extended to support function
2396 arguments and frame bases. Older versions of GDB could crash when they
2399 * C++ nested types and namespaces
2401 GDB's support for nested types and namespaces in C++ has been
2402 improved, especially if you use the DWARF 2 debugging format. (This
2403 is the default for recent versions of GCC on most platforms.)
2404 Specifically, if you have a class "Inner" defined within a class or
2405 namespace "Outer", then GDB realizes that the class's name is
2406 "Outer::Inner", not simply "Inner". This should greatly reduce the
2407 frequency of complaints about not finding RTTI symbols. In addition,
2408 if you are stopped at inside of a function defined within a namespace,
2409 GDB modifies its name lookup accordingly.
2411 * New native configurations
2413 NetBSD/amd64 x86_64-*-netbsd*
2414 OpenBSD/amd64 x86_64-*-openbsd*
2415 OpenBSD/alpha alpha*-*-openbsd*
2416 OpenBSD/sparc sparc-*-openbsd*
2417 OpenBSD/sparc64 sparc64-*-openbsd*
2419 * New debugging protocols
2421 M32R with SDI protocol m32r-*-elf*
2423 * "set prompt-escape-char" command deleted.
2425 The command "set prompt-escape-char" has been deleted. This command,
2426 and its very obscure effet on GDB's prompt, was never documented,
2427 tested, nor mentioned in the NEWS file.
2429 * OBSOLETE configurations and files
2431 Configurations that have been declared obsolete in this release have
2432 been commented out. Unless there is activity to revive these
2433 configurations, the next release of GDB will have their sources
2434 permanently REMOVED.
2436 Sun 3, running SunOS 3 m68*-*-sunos3*
2437 Sun 3, running SunOS 4 m68*-*-sunos4*
2438 Sun 2, running SunOS 3 m68000-*-sunos3*
2439 Sun 2, running SunOS 4 m68000-*-sunos4*
2440 Motorola 680x0 running LynxOS m68*-*-lynxos*
2441 AT&T 3b1/Unix pc m68*-att-*
2442 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2443 decstation mips-dec-* mips-little-*
2444 riscos mips-*-riscos* mips-*-sysv*
2445 sonymips mips-sony-*
2446 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2448 * REMOVED configurations and files
2450 SGI Irix-4.x mips-sgi-irix4 or iris4
2451 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2452 Z8000 simulator z8k-zilog-none or z8ksim
2453 Matsushita MN10200 w/simulator mn10200-*-*
2454 H8/500 simulator h8500-hitachi-hms or h8500hms
2455 HP/PA running BSD hppa*-*-bsd*
2456 HP/PA running OSF/1 hppa*-*-osf*
2457 HP/PA Pro target hppa*-*-pro*
2458 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2459 386BSD i[3456]86-*-bsd*
2460 Sequent family i[3456]86-sequent-sysv4*
2461 i[3456]86-sequent-sysv*
2462 i[3456]86-sequent-bsd*
2463 SPARC running LynxOS sparc-*-lynxos*
2464 SPARC running SunOS 4 sparc-*-sunos4*
2465 Tsqware Sparclet sparclet-*-*
2466 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2468 *** Changes in GDB 6.0:
2472 Support for debugging the Objective-C programming language has been
2473 integrated into GDB.
2475 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2477 DWARF 2's Call Frame Information makes available compiler generated
2478 information that more exactly describes the program's run-time stack.
2479 By using this information, GDB is able to provide more robust stack
2482 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2483 have been updated to use a new backtrace mechanism which includes
2484 DWARF 2 CFI support.
2488 GDB's remote protocol has been extended to include support for hosted
2489 file I/O (where the remote target uses GDB's file system). See GDB's
2490 remote protocol documentation for details.
2492 * All targets using the new architecture framework.
2494 All of GDB's targets have been updated to use the new internal
2495 architecture framework. The way is now open for future GDB releases
2496 to include cross-architecture native debugging support (i386 on amd64,
2499 * GNU/Linux's Thread Local Storage (TLS)
2501 GDB now includes support for for the GNU/Linux implementation of
2502 per-thread variables.
2504 * GNU/Linux's Native POSIX Thread Library (NPTL)
2506 GDB's thread code has been updated to work with either the new
2507 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2509 * Separate debug info.
2511 GDB, in conjunction with BINUTILS, now supports a mechanism for
2512 automatically loading debug information from a separate file. Instead
2513 of shipping full debug and non-debug versions of system libraries,
2514 system integrators can now instead ship just the stripped libraries
2515 and optional debug files.
2517 * DWARF 2 Location Expressions
2519 DWARF 2 Location Expressions allow the compiler to more completely
2520 describe the location of variables (even in optimized code) to the
2523 GDB now includes preliminary support for location expressions (support
2524 for DW_OP_piece is still missing).
2528 A number of long standing bugs that caused GDB to die while starting a
2529 Java application have been fixed. GDB's Java support is now
2530 considered "useable".
2532 * GNU/Linux support for fork, vfork, and exec.
2534 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2535 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2538 * GDB supports logging output to a file
2540 There are two new commands, "set logging" and "show logging", which can be
2541 used to capture GDB's output to a file.
2543 * The meaning of "detach" has changed for gdbserver
2545 The "detach" command will now resume the application, as documented. To
2546 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2549 * d10v, m68hc11 `regs' command deprecated
2551 The `info registers' command has been updated so that it displays the
2552 registers using a format identical to the old `regs' command.
2556 A new command, "maint set profile on/off", has been added. This command can
2557 be used to enable or disable profiling while running GDB, to profile a
2558 session or a set of commands. In addition there is a new configure switch,
2559 "--enable-profiling", which will cause GDB to be compiled with profiling
2560 data, for more informative profiling results.
2562 * Default MI syntax changed to "mi2".
2564 The default MI (machine interface) syntax, enabled by the command line
2565 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2566 "mi1", can be enabled by specifying the option "-i=mi1".
2568 Support for the original "mi0" syntax (included in GDB 5.0) has been
2571 Fix for gdb/192: removed extraneous space when displaying frame level.
2572 Fix for gdb/672: update changelist is now output in mi list format.
2573 Fix for gdb/702: a -var-assign that updates the value now shows up
2574 in a subsequent -var-update.
2576 * New native configurations.
2578 FreeBSD/amd64 x86_64-*-freebsd*
2580 * Multi-arched targets.
2582 HP/PA HPUX11 hppa*-*-hpux*
2583 Renesas M32R/D w/simulator m32r-*-elf*
2585 * OBSOLETE configurations and files
2587 Configurations that have been declared obsolete in this release have
2588 been commented out. Unless there is activity to revive these
2589 configurations, the next release of GDB will have their sources
2590 permanently REMOVED.
2592 Z8000 simulator z8k-zilog-none or z8ksim
2593 Matsushita MN10200 w/simulator mn10200-*-*
2594 H8/500 simulator h8500-hitachi-hms or h8500hms
2595 HP/PA running BSD hppa*-*-bsd*
2596 HP/PA running OSF/1 hppa*-*-osf*
2597 HP/PA Pro target hppa*-*-pro*
2598 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2599 Sequent family i[3456]86-sequent-sysv4*
2600 i[3456]86-sequent-sysv*
2601 i[3456]86-sequent-bsd*
2602 Tsqware Sparclet sparclet-*-*
2603 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2605 * REMOVED configurations and files
2608 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2609 IBM AIX PS/2 i[3456]86-*-aix
2610 i386 running Mach 3.0 i[3456]86-*-mach3*
2611 i386 running Mach i[3456]86-*-mach*
2612 i386 running OSF/1 i[3456]86-*osf1mk*
2613 HP/Apollo 68k Family m68*-apollo*-sysv*,
2615 m68*-hp-bsd*, m68*-hp-hpux*
2616 Argonaut Risc Chip (ARC) arc-*-*
2617 Mitsubishi D30V d30v-*-*
2618 Fujitsu FR30 fr30-*-elf*
2619 OS/9000 i[34]86-*-os9k
2620 I960 with MON960 i960-*-coff
2622 * MIPS $fp behavior changed
2624 The convenience variable $fp, for the MIPS, now consistently returns
2625 the address of the current frame's base. Previously, depending on the
2626 context, $fp could refer to either $sp or the current frame's base
2627 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2628 The GNU Source-Level Debugger''.
2630 *** Changes in GDB 5.3:
2632 * GNU/Linux shared library multi-threaded performance improved.
2634 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2635 `/proc', in preference to `ptrace' for memory reads. This may result
2636 in an improvement in the start-up time of multi-threaded, shared
2637 library applications when run under GDB. One GDB user writes: ``loads
2638 shared libs like mad''.
2640 * ``gdbserver'' now supports multi-threaded applications on some targets
2642 Support for debugging multi-threaded applications which use
2643 the GNU/Linux LinuxThreads package has been added for
2644 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2645 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2647 * GDB now supports C/C++ preprocessor macros.
2649 GDB now expands preprocessor macro invocations in C/C++ expressions,
2650 and provides various commands for showing macro definitions and how
2653 The new command `macro expand EXPRESSION' expands any macro
2654 invocations in expression, and shows the result.
2656 The new command `show macro MACRO-NAME' shows the definition of the
2657 macro named MACRO-NAME, and where it was defined.
2659 Most compilers don't include information about macros in the debugging
2660 information by default. In GCC 3.1, for example, you need to compile
2661 your program with the options `-gdwarf-2 -g3'. If the macro
2662 information is present in the executable, GDB will read it.
2664 * Multi-arched targets.
2666 DEC Alpha (partial) alpha*-*-*
2667 DEC VAX (partial) vax-*-*
2669 National Semiconductor NS32000 (partial) ns32k-*-*
2670 Motorola 68000 (partial) m68k-*-*
2671 Motorola MCORE mcore-*-*
2675 Fujitsu FRV architecture added by Red Hat frv*-*-*
2678 * New native configurations
2680 Alpha NetBSD alpha*-*-netbsd*
2681 SH NetBSD sh*-*-netbsdelf*
2682 MIPS NetBSD mips*-*-netbsd*
2683 UltraSPARC NetBSD sparc64-*-netbsd*
2685 * OBSOLETE configurations and files
2687 Configurations that have been declared obsolete in this release have
2688 been commented out. Unless there is activity to revive these
2689 configurations, the next release of GDB will have their sources
2690 permanently REMOVED.
2692 Mitsubishi D30V d30v-*-*
2693 OS/9000 i[34]86-*-os9k
2694 IBM AIX PS/2 i[3456]86-*-aix
2695 Fujitsu FR30 fr30-*-elf*
2696 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2697 Argonaut Risc Chip (ARC) arc-*-*
2698 i386 running Mach 3.0 i[3456]86-*-mach3*
2699 i386 running Mach i[3456]86-*-mach*
2700 i386 running OSF/1 i[3456]86-*osf1mk*
2701 HP/Apollo 68k Family m68*-apollo*-sysv*,
2703 m68*-hp-bsd*, m68*-hp-hpux*
2704 I960 with MON960 i960-*-coff
2706 * OBSOLETE languages
2708 CHILL, a Pascal like language used by telecommunications companies.
2710 * REMOVED configurations and files
2712 AMD 29k family via UDI a29k-amd-udi, udi29k
2713 A29K VxWorks a29k-*-vxworks
2714 AMD 29000 embedded, using EBMON a29k-none-none
2715 AMD 29000 embedded with COFF a29k-none-coff
2716 AMD 29000 embedded with a.out a29k-none-aout
2718 testsuite/gdb.hp/gdb.threads-hp/ directory
2720 * New command "set max-user-call-depth <nnn>"
2722 This command allows the user to limit the call depth of user-defined
2723 commands. The default is 1024.
2725 * Changes in FreeBSD/i386 native debugging.
2727 Support for the "generate-core-file" has been added.
2729 * New commands "dump", "append", and "restore".
2731 These commands allow data to be copied from target memory
2732 to a bfd-format or binary file (dump and append), and back
2733 from a file into memory (restore).
2735 * Improved "next/step" support on multi-processor Alpha Tru64.
2737 The previous single-step mechanism could cause unpredictable problems,
2738 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2739 of a software single-step mechanism prevents this.
2741 *** Changes in GDB 5.2.1:
2749 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2750 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2751 Fix, by Joel Brobecker imported from mainline.
2753 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2754 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2755 Fix, by Fred Fish, imported from mainline.
2757 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2758 Surprisingly enough, it works now.
2759 By Michal Ludvig, imported from mainline.
2761 i386 hardware watchpoint support:
2762 avoid misses on second run for some targets.
2763 By Pierre Muller, imported from mainline.
2765 *** Changes in GDB 5.2:
2767 * New command "set trust-readonly-sections on[off]".
2769 This command is a hint that tells gdb that read-only sections
2770 really are read-only (ie. that their contents will not change).
2771 In this mode, gdb will go to the object file rather than the
2772 target to read memory from read-only sections (such as ".text").
2773 This can be a significant performance improvement on some
2774 (notably embedded) targets.
2776 * New command "generate-core-file" (or "gcore").
2778 This new gdb command allows the user to drop a core file of the child
2779 process state at any time. So far it's been implemented only for
2780 GNU/Linux and Solaris, but should be relatively easily ported to other
2781 hosts. Argument is core file name (defaults to core.<pid>).
2783 * New command line option
2785 GDB now accepts --pid or -p followed by a process id.
2787 * Change in command line behavior -- corefiles vs. process ids.
2789 There is a subtle behavior in the way in which GDB handles
2790 command line arguments. The first non-flag argument is always
2791 a program to debug, but the second non-flag argument may either
2792 be a corefile or a process id. Previously, GDB would attempt to
2793 open the second argument as a corefile, and if that failed, would
2794 issue a superfluous error message and then attempt to attach it as
2795 a process. Now, if the second argument begins with a non-digit,
2796 it will be treated as a corefile. If it begins with a digit,
2797 GDB will attempt to attach it as a process, and if no such process
2798 is found, will then attempt to open it as a corefile.
2800 * Changes in ARM configurations.
2802 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2803 configuration is fully multi-arch.
2805 * New native configurations
2807 ARM NetBSD arm*-*-netbsd*
2808 x86 OpenBSD i[3456]86-*-openbsd*
2809 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2810 Sparc64 running FreeBSD sparc64-*-freebsd*
2814 Sanyo XStormy16 xstormy16-elf
2816 * OBSOLETE configurations and files
2818 Configurations that have been declared obsolete in this release have
2819 been commented out. Unless there is activity to revive these
2820 configurations, the next release of GDB will have their sources
2821 permanently REMOVED.
2823 AMD 29k family via UDI a29k-amd-udi, udi29k
2824 A29K VxWorks a29k-*-vxworks
2825 AMD 29000 embedded, using EBMON a29k-none-none
2826 AMD 29000 embedded with COFF a29k-none-coff
2827 AMD 29000 embedded with a.out a29k-none-aout
2829 testsuite/gdb.hp/gdb.threads-hp/ directory
2831 * REMOVED configurations and files
2833 TI TMS320C80 tic80-*-*
2835 PowerPC Solaris powerpcle-*-solaris*
2836 PowerPC Windows NT powerpcle-*-cygwin32
2837 PowerPC Netware powerpc-*-netware*
2838 Harris/CXUX m88k m88*-harris-cxux*
2839 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2840 ns32k-utek-sysv* ns32k-utek-*
2841 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2842 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2843 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2844 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2845 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2847 * Changes to command line processing
2849 The new `--args' feature can be used to specify command-line arguments
2850 for the inferior from gdb's command line.
2852 * Changes to key bindings
2854 There is a new `operate-and-get-next' function bound to `C-o'.
2856 *** Changes in GDB 5.1.1
2858 Fix compile problem on DJGPP.
2860 Fix a problem with floating-point registers on the i386 being
2863 Fix to stop GDB crashing on .debug_str debug info.
2865 Numerous documentation fixes.
2867 Numerous testsuite fixes.
2869 *** Changes in GDB 5.1:
2871 * New native configurations
2873 Alpha FreeBSD alpha*-*-freebsd*
2874 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2875 MIPS GNU/Linux mips*-*-linux*
2876 MIPS SGI Irix 6.x mips*-sgi-irix6*
2877 ia64 AIX ia64-*-aix*
2878 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2882 Motorola 68HC11 and 68HC12 m68hc11-elf
2884 UltraSparc running GNU/Linux sparc64-*-linux*
2886 * OBSOLETE configurations and files
2888 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2889 Harris/CXUX m88k m88*-harris-cxux*
2890 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2891 ns32k-utek-sysv* ns32k-utek-*
2892 TI TMS320C80 tic80-*-*
2894 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2895 PowerPC Solaris powerpcle-*-solaris*
2896 PowerPC Windows NT powerpcle-*-cygwin32
2897 PowerPC Netware powerpc-*-netware*
2898 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2899 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2900 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2901 Apple Macintosh (MPW) host N/A
2903 stuff.c (Program to stuff files into a specially prepared space in kdb)
2904 kdb-start.c (Main loop for the standalone kernel debugger)
2906 Configurations that have been declared obsolete in this release have
2907 been commented out. Unless there is activity to revive these
2908 configurations, the next release of GDB will have their sources
2909 permanently REMOVED.
2911 * REMOVED configurations and files
2913 Altos 3068 m68*-altos-*
2914 Convex c1-*-*, c2-*-*
2916 ARM RISCix arm-*-* (as host)
2920 * GDB has been converted to ISO C.
2922 GDB's source code has been converted to ISO C. In particular, the
2923 sources are fully protoized, and rely on standard headers being
2928 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2930 * The MI enabled by default.
2932 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2933 revised and enabled by default. Packages which use GDB as a debugging
2934 engine behind a UI or another front end are encouraged to switch to
2935 using the GDB/MI interface, instead of the old annotations interface
2936 which is now deprecated.
2938 * Support for debugging Pascal programs.
2940 GDB now includes support for debugging Pascal programs. The following
2941 main features are supported:
2943 - Pascal-specific data types such as sets;
2945 - automatic recognition of Pascal sources based on file-name
2948 - Pascal-style display of data types, variables, and functions;
2950 - a Pascal expression parser.
2952 However, some important features are not yet supported.
2954 - Pascal string operations are not supported at all;
2956 - there are some problems with boolean types;
2958 - Pascal type hexadecimal constants are not supported
2959 because they conflict with the internal variables format;
2961 - support for Pascal objects and classes is not full yet;
2963 - unlike Pascal, GDB is case-sensitive for symbol names.
2965 * Changes in completion.
2967 Commands such as `shell', `run' and `set args', which pass arguments
2968 to inferior programs, now complete on file names, similar to what
2969 users expect at the shell prompt.
2971 Commands which accept locations, such as `disassemble', `print',
2972 `breakpoint', `until', etc. now complete on filenames as well as
2973 program symbols. Thus, if you type "break foob TAB", and the source
2974 files linked into the programs include `foobar.c', that file name will
2975 be one of the candidates for completion. However, file names are not
2976 considered for completion after you typed a colon that delimits a file
2977 name from a name of a function in that file, as in "break foo.c:bar".
2979 `set demangle-style' completes on available demangling styles.
2981 * New platform-independent commands:
2983 It is now possible to define a post-hook for a command as well as a
2984 hook that runs before the command. For more details, see the
2985 documentation of `hookpost' in the GDB manual.
2987 * Changes in GNU/Linux native debugging.
2989 Support for debugging multi-threaded programs has been completely
2990 revised for all platforms except m68k and sparc. You can now debug as
2991 many threads as your system allows you to have.
2993 Attach/detach is supported for multi-threaded programs.
2995 Support for SSE registers was added for x86. This doesn't work for
2996 multi-threaded programs though.
2998 * Changes in MIPS configurations.
3000 Multi-arch support is enabled for all MIPS configurations.
3002 GDB can now be built as native debugger on SGI Irix 6.x systems for
3003 debugging n32 executables. (Debugging 64-bit executables is not yet
3006 * Unified support for hardware watchpoints in all x86 configurations.
3008 Most (if not all) native x86 configurations support hardware-assisted
3009 breakpoints and watchpoints in a unified manner. This support
3010 implements debug register sharing between watchpoints, which allows to
3011 put a virtually infinite number of watchpoints on the same address,
3012 and also supports watching regions up to 16 bytes with several debug
3015 The new maintenance command `maintenance show-debug-regs' toggles
3016 debugging print-outs in functions that insert, remove, and test
3017 watchpoints and hardware breakpoints.
3019 * Changes in the DJGPP native configuration.
3021 New command ``info dos sysinfo'' displays assorted information about
3022 the CPU, OS, memory, and DPMI server.
3024 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3025 display information about segment descriptors stored in GDT, LDT, and
3028 New commands ``info dos pde'' and ``info dos pte'' display entries
3029 from Page Directory and Page Tables (for now works with CWSDPMI only).
3030 New command ``info dos address-pte'' displays the Page Table entry for
3031 a given linear address.
3033 GDB can now pass command lines longer than 126 characters to the
3034 program being debugged (requires an update to the libdbg.a library
3035 which is part of the DJGPP development kit).
3037 DWARF2 debug info is now supported.
3039 It is now possible to `step' and `next' through calls to `longjmp'.
3041 * Changes in documentation.
3043 All GDB documentation was converted to GFDL, the GNU Free
3044 Documentation License.
3046 Tracepoints-related commands are now fully documented in the GDB
3049 TUI, the Text-mode User Interface, is now documented in the manual.
3051 Tracepoints-related commands are now fully documented in the GDB
3054 The "GDB Internals" manual now has an index. It also includes
3055 documentation of `ui_out' functions, GDB coding standards, x86
3056 hardware watchpoints, and memory region attributes.
3058 * GDB's version number moved to ``version.in''
3060 The Makefile variable VERSION has been replaced by the file
3061 ``version.in''. People creating GDB distributions should update the
3062 contents of this file.
3066 GUD support is now a standard part of the EMACS distribution.
3068 *** Changes in GDB 5.0:
3070 * Improved support for debugging FP programs on x86 targets
3072 Unified and much-improved support for debugging floating-point
3073 programs on all x86 targets. In particular, ``info float'' now
3074 displays the FP registers in the same format on all x86 targets, with
3075 greater level of detail.
3077 * Improvements and bugfixes in hardware-assisted watchpoints
3079 It is now possible to watch array elements, struct members, and
3080 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3081 on x86 targets no longer erroneously trigger when the address is
3084 * Improvements in the native DJGPP version of GDB
3086 The distribution now includes all the scripts and auxiliary files
3087 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3088 machines ``out of the box''.
3090 The DJGPP version can now debug programs that use signals. It is
3091 possible to catch signals that happened in the debuggee, deliver
3092 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3093 would kill the program being debugged.) Programs that hook hardware
3094 interrupts (keyboard, timer, etc.) can also be debugged.
3096 It is now possible to debug DJGPP programs that redirect their
3097 standard handles or switch them to raw (as opposed to cooked) mode, or
3098 even close them. The command ``run < foo > bar'' works as expected,
3099 and ``info terminal'' reports useful information about the debuggee's
3100 terminal, including raw/cooked mode, redirection, etc.
3102 The DJGPP version now uses termios functions for console I/O, which
3103 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3106 DOS-style file names with drive letters are now fully supported by
3109 It is now possible to debug DJGPP programs that switch their working
3110 directory. It is also possible to rerun the debuggee any number of
3111 times without restarting GDB; thus, you can use the same setup,
3112 breakpoints, etc. for many debugging sessions.
3114 * New native configurations
3116 ARM GNU/Linux arm*-*-linux*
3117 PowerPC GNU/Linux powerpc-*-linux*
3121 Motorola MCore mcore-*-*
3122 x86 VxWorks i[3456]86-*-vxworks*
3123 PowerPC VxWorks powerpc-*-vxworks*
3124 TI TMS320C80 tic80-*-*
3126 * OBSOLETE configurations
3128 Altos 3068 m68*-altos-*
3129 Convex c1-*-*, c2-*-*
3131 ARM RISCix arm-*-* (as host)
3134 Configurations that have been declared obsolete will be commented out,
3135 but the code will be left in place. If there is no activity to revive
3136 these configurations before the next release of GDB, the sources will
3137 be permanently REMOVED.
3139 * Gould support removed
3141 Support for the Gould PowerNode and NP1 has been removed.
3143 * New features for SVR4
3145 On SVR4 native platforms (such as Solaris), if you attach to a process
3146 without first loading a symbol file, GDB will now attempt to locate and
3147 load symbols from the running process's executable file.
3149 * Many C++ enhancements
3151 C++ support has been greatly improved. Overload resolution now works properly
3152 in almost all cases. RTTI support is on the way.
3154 * Remote targets can connect to a sub-program
3156 A popen(3) style serial-device has been added. This device starts a
3157 sub-process (such as a stand-alone simulator) and then communicates
3158 with that. The sub-program to run is specified using the syntax
3159 ``|<program> <args>'' vis:
3161 (gdb) set remotedebug 1
3162 (gdb) target extended-remote |mn10300-elf-sim program-args
3164 * MIPS 64 remote protocol
3166 A long standing bug in the mips64 remote protocol where by GDB
3167 expected certain 32 bit registers (ex SR) to be transfered as 32
3168 instead of 64 bits has been fixed.
3170 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3171 added to provide backward compatibility with older versions of GDB.
3173 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3175 The command ``set remotebinarydownload'' command has been replaced by
3176 ``set remote X-packet''. Other commands in ``set remote'' family
3177 include ``set remote P-packet''.
3179 * Breakpoint commands accept ranges.
3181 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3182 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3183 ``tracepoint passcount'' also accepts a range of tracepoints.
3185 * ``apropos'' command added.
3187 The ``apropos'' command searches through command names and
3188 documentation strings, printing out matches, making it much easier to
3189 try to find a command that does what you are looking for.
3193 A new machine oriented interface (MI) has been added to GDB. This
3194 interface is designed for debug environments running GDB as a separate
3195 process. This is part of the long term libGDB project. See the
3196 "GDB/MI" chapter of the GDB manual for further information. It can be
3197 enabled by configuring with:
3199 .../configure --enable-gdbmi
3201 *** Changes in GDB-4.18:
3203 * New native configurations
3205 HP-UX 10.20 hppa*-*-hpux10.20
3206 HP-UX 11.x hppa*-*-hpux11.0*
3207 M68K GNU/Linux m68*-*-linux*
3211 Fujitsu FR30 fr30-*-elf*
3212 Intel StrongARM strongarm-*-*
3213 Mitsubishi D30V d30v-*-*
3215 * OBSOLETE configurations
3217 Gould PowerNode, NP1 np1-*-*, pn-*-*
3219 Configurations that have been declared obsolete will be commented out,
3220 but the code will be left in place. If there is no activity to revive
3221 these configurations before the next release of GDB, the sources will
3222 be permanently REMOVED.
3226 As a compatibility experiment, GDB's source files buildsym.h and
3227 buildsym.c have been converted to pure standard C, no longer
3228 containing any K&R compatibility code. We believe that all systems in
3229 use today either come with a standard C compiler, or have a GCC port
3230 available. If this is not true, please report the affected
3231 configuration to bug-gdb@gnu.org immediately. See the README file for
3232 information about getting a standard C compiler if you don't have one
3237 GDB now uses readline 2.2.
3239 * set extension-language
3241 You can now control the mapping between filename extensions and source
3242 languages by using the `set extension-language' command. For instance,
3243 you can ask GDB to treat .c files as C++ by saying
3244 set extension-language .c c++
3245 The command `info extensions' lists all of the recognized extensions
3246 and their associated languages.
3248 * Setting processor type for PowerPC and RS/6000
3250 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3251 you can use the `set processor' command to specify what variant of the
3252 PowerPC family you are debugging. The command
3256 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3257 following PowerPC and RS6000 variants:
3259 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3260 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3262 403GC IBM PowerPC 403GC
3263 505 Motorola PowerPC 505
3264 860 Motorola PowerPC 860 or 850
3265 601 Motorola PowerPC 601
3266 602 Motorola PowerPC 602
3267 603 Motorola/IBM PowerPC 603 or 603e
3268 604 Motorola PowerPC 604 or 604e
3269 750 Motorola/IBM PowerPC 750 or 750
3271 At the moment, this command just tells GDB what to name the
3272 special-purpose processor registers. Since almost all the affected
3273 registers are inaccessible to user-level programs, this command is
3274 only useful for remote debugging in its present form.
3278 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3279 more extensive support for HP-UX. Added features include shared
3280 library support, kernel threads and hardware watchpoints for 11.00,
3281 support for HP's ANSI C and C++ compilers, and a compatibility mode
3282 for xdb and dbx commands.
3286 HP's donation includes the new concept of catchpoints, which is a
3287 generalization of the old catch command. On HP-UX, it is now possible
3288 to catch exec, fork, and vfork, as well as library loading.
3290 This means that the existing catch command has changed; its first
3291 argument now specifies the type of catch to be set up. See the
3292 output of "help catch" for a list of catchpoint types.
3294 * Debugging across forks
3296 On HP-UX, you can choose which process to debug when a fork() happens
3301 HP has donated a curses-based terminal user interface (TUI). To get
3302 it, build with --enable-tui. Although this can be enabled for any
3303 configuration, at present it only works for native HP debugging.
3305 * GDB remote protocol additions
3307 A new protocol packet 'X' that writes binary data is now available.
3308 Default behavior is to try 'X', then drop back to 'M' if the stub
3309 fails to respond. The settable variable `remotebinarydownload'
3310 allows explicit control over the use of 'X'.
3312 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3313 full 64-bit address. The command
3315 set remoteaddresssize 32
3317 can be used to revert to the old behaviour. For existing remote stubs
3318 the change should not be noticed, as the additional address information
3321 In order to assist in debugging stubs, you may use the maintenance
3322 command `packet' to send any text string to the stub. For instance,
3324 maint packet heythere
3326 sends the packet "$heythere#<checksum>". Note that it is very easy to
3327 disrupt a debugging session by sending the wrong packet at the wrong
3330 The compare-sections command allows you to compare section data on the
3331 target to what is in the executable file without uploading or
3332 downloading, by comparing CRC checksums.
3334 * Tracing can collect general expressions
3336 You may now collect general expressions at tracepoints. This requires
3337 further additions to the target-side stub; see tracepoint.c and
3338 doc/agentexpr.texi for further details.
3340 * mask-address variable for Mips
3342 For Mips targets, you may control the zeroing of the upper 32 bits of
3343 a 64-bit address by entering `set mask-address on'. This is mainly
3344 of interest to users of embedded R4xxx and R5xxx processors.
3346 * Higher serial baud rates
3348 GDB's serial code now allows you to specify baud rates 57600, 115200,
3349 230400, and 460800 baud. (Note that your host system may not be able
3350 to achieve all of these rates.)
3354 The i960 configuration now includes an initial implementation of a
3355 builtin simulator, contributed by Jim Wilson.
3358 *** Changes in GDB-4.17:
3360 * New native configurations
3362 Alpha GNU/Linux alpha*-*-linux*
3363 Unixware 2.x i[3456]86-unixware2*
3364 Irix 6.x mips*-sgi-irix6*
3365 PowerPC GNU/Linux powerpc-*-linux*
3366 PowerPC Solaris powerpcle-*-solaris*
3367 Sparc GNU/Linux sparc-*-linux*
3368 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3372 Argonaut Risc Chip (ARC) arc-*-*
3373 Hitachi H8/300S h8300*-*-*
3374 Matsushita MN10200 w/simulator mn10200-*-*
3375 Matsushita MN10300 w/simulator mn10300-*-*
3376 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3377 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3378 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3379 Mitsubishi D10V w/simulator d10v-*-*
3380 Mitsubishi M32R/D w/simulator m32r-*-elf*
3381 Tsqware Sparclet sparclet-*-*
3382 NEC V850 w/simulator v850-*-*
3384 * New debugging protocols
3386 ARM with RDI protocol arm*-*-*
3387 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3388 DDB and LSI variants of PMON protocol mips*-*-*
3389 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3390 PowerPC with SDS protocol powerpc{,le}-*-eabi
3391 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3395 All configurations can now understand and use the DWARF 2 debugging
3396 format. The choice is automatic, if the symbol file contains DWARF 2
3401 GDB now includes basic Java language support. This support is
3402 only useful with Java compilers that produce native machine code.
3404 * solib-absolute-prefix and solib-search-path
3406 For SunOS and SVR4 shared libraries, you may now set the prefix for
3407 loading absolute shared library symbol files, and the search path for
3408 locating non-absolute shared library symbol files.
3410 * Live range splitting
3412 GDB can now effectively debug code for which GCC has performed live
3413 range splitting as part of its optimization. See gdb/doc/LRS for
3414 more details on the expected format of the stabs information.
3418 GDB's support for the GNU Hurd, including thread debugging, has been
3419 updated to work with current versions of the Hurd.
3423 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3424 instruction set. ARM GDB automatically detects when Thumb
3425 instructions are in use, and adjusts disassembly and backtracing
3430 GDB's MIPS target configurations now handle the MIP16 16-bit
3435 GDB now includes support for overlays; if an executable has been
3436 linked such that multiple sections are based at the same address, GDB
3437 will decide which section to use for symbolic info. You can choose to
3438 control the decision manually, using overlay commands, or implement
3439 additional target-side support and use "overlay load-target" to bring
3440 in the overlay mapping. Do "help overlay" for more detail.
3444 The command "info symbol <address>" displays information about
3445 the symbol at the specified address.
3449 The standard remote protocol now includes an extension that allows
3450 asynchronous collection and display of trace data. This requires
3451 extensive support in the target-side debugging stub. Tracing mode
3452 includes a new interaction mode in GDB and new commands: see the
3453 file tracepoint.c for more details.
3457 Configurations for embedded MIPS now include a simulator contributed
3458 by Cygnus Solutions. The simulator supports the instruction sets
3459 of most MIPS variants.
3463 Sparc configurations may now include the ERC32 simulator contributed
3464 by the European Space Agency. The simulator is not built into
3465 Sparc targets by default; configure with --enable-sim to include it.
3469 For target configurations that may include multiple variants of a
3470 basic architecture (such as MIPS and SH), you may now set the
3471 architecture explicitly. "set arch" sets, "info arch" lists
3472 the possible architectures.
3474 *** Changes in GDB-4.16:
3476 * New native configurations
3478 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3479 M68K NetBSD m68k-*-netbsd*
3480 PowerPC AIX 4.x powerpc-*-aix*
3481 PowerPC MacOS powerpc-*-macos*
3482 PowerPC Windows NT powerpcle-*-cygwin32
3483 RS/6000 AIX 4.x rs6000-*-aix4*
3487 ARM with RDP protocol arm-*-*
3488 I960 with MON960 i960-*-coff
3489 MIPS VxWorks mips*-*-vxworks*
3490 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3491 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3493 Matra Sparclet sparclet-*-*
3497 The powerpc-eabi configuration now includes the PSIM simulator,
3498 contributed by Andrew Cagney, with assistance from Mike Meissner.
3499 PSIM is a very elaborate model of the PowerPC, including not only
3500 basic instruction set execution, but also details of execution unit
3501 performance and I/O hardware. See sim/ppc/README for more details.
3505 GDB now works with Solaris 2.5.
3507 * Windows 95/NT native
3509 GDB will now work as a native debugger on Windows 95 and Windows NT.
3510 To build it from source, you must use the "gnu-win32" environment,
3511 which uses a DLL to emulate enough of Unix to run the GNU tools.
3512 Further information, binaries, and sources are available at
3513 ftp.cygnus.com, under pub/gnu-win32.
3515 * dont-repeat command
3517 If a user-defined command includes the command `dont-repeat', then the
3518 command will not be repeated if the user just types return. This is
3519 useful if the command is time-consuming to run, so that accidental
3520 extra keystrokes don't run the same command many times.
3522 * Send break instead of ^C
3524 The standard remote protocol now includes an option to send a break
3525 rather than a ^C to the target in order to interrupt it. By default,
3526 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3528 * Remote protocol timeout
3530 The standard remote protocol includes a new variable `remotetimeout'
3531 that allows you to set the number of seconds before GDB gives up trying
3532 to read from the target. The default value is 2.
3534 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3536 By default GDB will automatically keep track of objects as they are
3537 loaded and unloaded by the dynamic linker. By using the command `set
3538 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3539 when shared library events occur, thus allowing you to set breakpoints
3540 in shared libraries which are explicitly loaded by the inferior.
3542 Note this feature does not work on hpux8. On hpux9 you must link
3543 /usr/lib/end.o into your program. This feature should work
3544 automatically on hpux10.
3546 * Irix 5.x hardware watchpoint support
3548 Irix 5 configurations now support the use of hardware watchpoints.
3550 * Mips protocol "SYN garbage limit"
3552 When debugging a Mips target using the `target mips' protocol, you
3553 may set the number of characters that GDB will ignore by setting
3554 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3555 every character. The default value is 1050.
3557 * Recording and replaying remote debug sessions
3559 If you set `remotelogfile' to the name of a file, gdb will write to it
3560 a recording of a remote debug session. This recording may then be
3561 replayed back to gdb using "gdbreplay". See gdbserver/README for
3562 details. This is useful when you have a problem with GDB while doing
3563 remote debugging; you can make a recording of the session and send it
3564 to someone else, who can then recreate the problem.
3566 * Speedups for remote debugging
3568 GDB includes speedups for downloading and stepping MIPS systems using
3569 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3570 and more efficient S-record downloading.
3572 * Memory use reductions and statistics collection
3574 GDB now uses less memory and reports statistics about memory usage.
3575 Try the `maint print statistics' command, for example.
3577 *** Changes in GDB-4.15:
3579 * Psymtabs for XCOFF
3581 The symbol reader for AIX GDB now uses partial symbol tables. This
3582 can greatly improve startup time, especially for large executables.
3584 * Remote targets use caching
3586 Remote targets now use a data cache to speed up communication with the
3587 remote side. The data cache could lead to incorrect results because
3588 it doesn't know about volatile variables, thus making it impossible to
3589 debug targets which use memory mapped I/O devices. `set remotecache
3590 off' turns the the data cache off.
3592 * Remote targets may have threads
3594 The standard remote protocol now includes support for multiple threads
3595 in the target system, using new protocol commands 'H' and 'T'. See
3596 gdb/remote.c for details.
3600 If GDB is configured with `--enable-netrom', then it will include
3601 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3602 acts as though it is a bank of ROM on the target board, but you can
3603 write into it over the network. GDB's support consists only of
3604 support for fast loading into the emulated ROM; to debug, you must use
3605 another protocol, such as standard remote protocol. The usual
3606 sequence is something like
3608 target nrom <netrom-hostname>
3610 target remote <netrom-hostname>:1235
3614 GDB now includes support for the Apple Macintosh, as a host only. It
3615 may be run as either an MPW tool or as a standalone application, and
3616 it can debug through the serial port. All the usual GDB commands are
3617 available, but to the target command, you must supply "serial" as the
3618 device type instead of "/dev/ttyXX". See mpw-README in the main
3619 directory for more information on how to build. The MPW configuration
3620 scripts */mpw-config.in support only a few targets, and only the
3621 mips-idt-ecoff target has been tested.
3625 GDB configuration now uses autoconf. This is not user-visible,
3626 but does simplify configuration and building.
3630 GDB now supports hpux10.
3632 *** Changes in GDB-4.14:
3634 * New native configurations
3636 x86 FreeBSD i[345]86-*-freebsd
3637 x86 NetBSD i[345]86-*-netbsd
3638 NS32k NetBSD ns32k-*-netbsd
3639 Sparc NetBSD sparc-*-netbsd
3643 A29K VxWorks a29k-*-vxworks
3644 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3645 CPU32 EST-300 emulator m68*-*-est*
3646 PowerPC ELF powerpc-*-elf
3649 * Alpha OSF/1 support for procfs
3651 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3652 possible to attach to running processes. As the mounting of the /proc
3653 filesystem is optional on the Alpha, GDB automatically determines
3654 the availability of /proc during startup. This can lead to problems
3655 if /proc is unmounted after GDB has been started.
3657 * Arguments to user-defined commands
3659 User commands may accept up to 10 arguments separated by whitespace.
3660 Arguments are accessed within the user command via $arg0..$arg9. A
3663 print $arg0 + $arg1 + $arg2
3665 To execute the command use:
3668 Defines the command "adder" which prints the sum of its three arguments.
3669 Note the arguments are text substitutions, so they may reference variables,
3670 use complex expressions, or even perform inferior function calls.
3672 * New `if' and `while' commands
3674 This makes it possible to write more sophisticated user-defined
3675 commands. Both commands take a single argument, which is the
3676 expression to evaluate, and must be followed by the commands to
3677 execute, one per line, if the expression is nonzero, the list being
3678 terminated by the word `end'. The `if' command list may include an
3679 `else' word, which causes the following commands to be executed only
3680 if the expression is zero.
3682 * Fortran source language mode
3684 GDB now includes partial support for Fortran 77. It will recognize
3685 Fortran programs and can evaluate a subset of Fortran expressions, but
3686 variables and functions may not be handled correctly. GDB will work
3687 with G77, but does not yet know much about symbols emitted by other
3690 * Better HPUX support
3692 Most debugging facilities now work on dynamic executables for HPPAs
3693 running hpux9 or later. You can attach to running dynamically linked
3694 processes, but by default the dynamic libraries will be read-only, so
3695 for instance you won't be able to put breakpoints in them. To change
3696 that behavior do the following before running the program:
3702 This will cause the libraries to be mapped private and read-write.
3703 To revert to the normal behavior, do this:
3709 You cannot set breakpoints or examine data in the library until after
3710 the library is loaded if the function/data symbols do not have
3713 GDB can now also read debug symbols produced by the HP C compiler on
3714 HPPAs (sorry, no C++, Fortran or 68k support).
3716 * Target byte order now dynamically selectable
3718 You can choose which byte order to use with a target system, via the
3719 commands "set endian big" and "set endian little", and you can see the
3720 current setting by using "show endian". You can also give the command
3721 "set endian auto", in which case GDB will use the byte order
3722 associated with the executable. Currently, only embedded MIPS
3723 configurations support dynamic selection of target byte order.
3725 * New DOS host serial code
3727 This version uses DPMI interrupts to handle buffered I/O, so you
3728 no longer need to run asynctsr when debugging boards connected to
3731 *** Changes in GDB-4.13:
3733 * New "complete" command
3735 This lists all the possible completions for the rest of the line, if it
3736 were to be given as a command itself. This is intended for use by emacs.
3738 * Trailing space optional in prompt
3740 "set prompt" no longer adds a space for you after the prompt you set. This
3741 allows you to set a prompt which ends in a space or one that does not.
3743 * Breakpoint hit counts
3745 "info break" now displays a count of the number of times the breakpoint
3746 has been hit. This is especially useful in conjunction with "ignore"; you
3747 can ignore a large number of breakpoint hits, look at the breakpoint info
3748 to see how many times the breakpoint was hit, then run again, ignoring one
3749 less than that number, and this will get you quickly to the last hit of
3752 * Ability to stop printing at NULL character
3754 "set print null-stop" will cause GDB to stop printing the characters of
3755 an array when the first NULL is encountered. This is useful when large
3756 arrays actually contain only short strings.
3758 * Shared library breakpoints
3760 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3761 breakpoints in shared libraries before the executable is run.
3763 * Hardware watchpoints
3765 There is a new hardware breakpoint for the watch command for sparclite
3766 targets. See gdb/sparclite/hw_breakpoint.note.
3768 Hardware watchpoints are also now supported under GNU/Linux.
3772 Annotations have been added. These are for use with graphical interfaces,
3773 and are still experimental. Currently only gdba.el uses these.
3775 * Improved Irix 5 support
3777 GDB now works properly with Irix 5.2.
3779 * Improved HPPA support
3781 GDB now works properly with the latest GCC and GAS.
3783 * New native configurations
3785 Sequent PTX4 i[34]86-sequent-ptx4
3786 HPPA running OSF/1 hppa*-*-osf*
3787 Atari TT running SVR4 m68*-*-sysv4*
3788 RS/6000 LynxOS rs6000-*-lynxos*
3792 OS/9000 i[34]86-*-os9k
3793 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3796 * Hitachi SH7000 and E7000-PC ICE support
3798 There is now support for communicating with the Hitachi E7000-PC ICE.
3799 This is available automatically when GDB is configured for the SH.
3803 As usual, a variety of small fixes and improvements, both generic
3804 and configuration-specific. See the ChangeLog for more detail.
3806 *** Changes in GDB-4.12:
3808 * Irix 5 is now supported
3812 GDB-4.12 on the HPPA has a number of changes which make it unable
3813 to debug the output from the currently released versions of GCC and
3814 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3815 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3816 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3819 *** Changes in GDB-4.11:
3821 * User visible changes:
3825 The "set remotedebug" option is now consistent between the mips remote
3826 target, remote targets using the gdb-specific protocol, UDI (AMD's
3827 debug protocol for the 29k) and the 88k bug monitor. It is now an
3828 integer specifying a debug level (normally 0 or 1, but 2 means more
3829 debugging info for the mips target).
3831 * DEC Alpha native support
3833 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3834 debug info, but GDB works fairly well with the DEC compiler and should
3835 work with a future GCC release. See the README file for a few
3836 Alpha-specific notes.
3838 * Preliminary thread implementation
3840 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3842 * LynxOS native and target support for 386
3844 This release has been hosted on LynxOS 2.2, and also can be configured
3845 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3848 * Improvements in C++ mangling/demangling.
3850 This release has much better g++ debugging, specifically in name
3851 mangling/demangling, virtual function calls, print virtual table,
3852 call methods, ...etc.
3854 *** Changes in GDB-4.10:
3856 * User visible changes:
3858 Remote debugging using the GDB-specific (`target remote') protocol now
3859 supports the `load' command. This is only useful if you have some
3860 other way of getting the stub to the target system, and you can put it
3861 somewhere in memory where it won't get clobbered by the download.
3863 Filename completion now works.
3865 When run under emacs mode, the "info line" command now causes the
3866 arrow to point to the line specified. Also, "info line" prints
3867 addresses in symbolic form (as well as hex).
3869 All vxworks based targets now support a user settable option, called
3870 vxworks-timeout. This option represents the number of seconds gdb
3871 should wait for responses to rpc's. You might want to use this if
3872 your vxworks target is, perhaps, a slow software simulator or happens
3873 to be on the far side of a thin network line.
3877 This release contains support for using a DEC alpha as a GDB host for
3878 cross debugging. Native alpha debugging is not supported yet.
3881 *** Changes in GDB-4.9:
3885 This is the first GDB release which is accompanied by a matching testsuite.
3886 The testsuite requires installation of dejagnu, which should be available
3887 via ftp from most sites that carry GNU software.
3891 'Cfront' style demangling has had its name changed to 'ARM' style, to
3892 emphasize that it was written from the specifications in the C++ Annotated
3893 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3894 disclaimers, it still generated too much confusion with users attempting to
3895 use gdb with AT&T cfront.
3899 GDB now uses a standard remote interface to a simulator library.
3900 So far, the library contains simulators for the Zilog Z8001/2, the
3901 Hitachi H8/300, H8/500 and Super-H.
3903 * New targets supported
3905 H8/300 simulator h8300-hitachi-hms or h8300hms
3906 H8/500 simulator h8500-hitachi-hms or h8500hms
3907 SH simulator sh-hitachi-hms or sh
3908 Z8000 simulator z8k-zilog-none or z8ksim
3909 IDT MIPS board over serial line mips-idt-ecoff
3911 Cross-debugging to GO32 targets is supported. It requires a custom
3912 version of the i386-stub.c module which is integrated with the
3913 GO32 memory extender.
3915 * New remote protocols
3917 MIPS remote debugging protocol.
3919 * New source languages supported
3921 This version includes preliminary support for Chill, a Pascal like language
3922 used by telecommunications companies. Chill support is also being integrated
3923 into the GNU compiler, but we don't know when it will be publically available.
3926 *** Changes in GDB-4.8:
3928 * HP Precision Architecture supported
3930 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3931 version of this support was available as a set of patches from the
3932 University of Utah. GDB does not support debugging of programs
3933 compiled with the HP compiler, because HP will not document their file
3934 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3935 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3937 Many problems in the preliminary version have been fixed.
3939 * Faster and better demangling
3941 We have improved template demangling and fixed numerous bugs in the GNU style
3942 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3943 character types (wchar_t) are now supported. Demangling of each symbol is now
3944 only done once, and is cached when the symbol table for a file is read in.
3945 This results in a small increase in memory usage for C programs, a moderate
3946 increase in memory usage for C++ programs, and a fantastic speedup in
3949 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3950 from the specifications in the Annotated Reference Manual, which AT&T's
3951 compiler does not actually implement.
3953 * G++ multiple inheritance compiler problem
3955 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3956 inheritance lattices was reworked to properly discover ambiguities. We
3957 recently found an example which causes this new algorithm to fail in a
3958 very subtle way, producing bad debug information for those classes.
3959 The file 'gcc.patch' (in this directory) can be applied to gcc to
3960 circumvent the problem. A future GCC release will contain a complete
3963 The previous G++ debug info problem (mentioned below for the gdb-4.7
3964 release) is fixed in gcc version 2.3.2.
3966 * Improved configure script
3968 The `configure' script will now attempt to guess your system type if
3969 you don't supply a host system type. The old scheme of supplying a
3970 host system triplet is preferable over using this. All the magic is
3971 done in the new `config.guess' script. Examine it for details.
3973 We have also brought our configure script much more in line with the FSF's
3974 version. It now supports the --with-xxx options. In particular,
3975 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3976 The resulting GDB will not be able to read arbitrary object file formats --
3977 only the format ``expected'' to be used on the configured target system.
3978 We hope to make this the default in a future release.
3980 * Documentation improvements
3982 There's new internal documentation on how to modify GDB, and how to
3983 produce clean changes to the code. We implore people to read it
3984 before submitting changes.
3986 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3987 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3988 `info' files are also provided. To build `info' files from scratch,
3989 you will need the latest `makeinfo' release, which will be available in
3990 a future texinfo-X.Y release.
3992 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3993 We're not sure exactly which versions have this problem, but it has
3994 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3995 or better. If that isn't possible, there is a patch in
3996 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3997 around this problem.
4001 GDB now supports array constants that can be used in expressions typed in by
4002 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4003 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4006 The new directory `gdb/sparclite' contains a program that demonstrates
4007 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4009 * New native hosts supported
4011 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4012 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4014 * New targets supported
4016 AMD 29k family via UDI a29k-amd-udi or udi29k
4018 * New file formats supported
4020 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4021 HPUX core files, and SCO 3.2v2 core files.
4025 Attaching to processes now works again; thanks for the many bug reports.
4027 We have also stomped on a bunch of core dumps caused by
4028 printf_filtered("%s") problems.
4030 We eliminated a copyright problem on the rpc and ptrace header files
4031 for VxWorks, which was discovered at the last minute during the 4.7
4032 release. You should now be able to build a VxWorks GDB.
4034 You can now interrupt gdb while an attached process is running. This
4035 will cause the attached process to stop, and give control back to GDB.
4037 We fixed problems caused by using too many file descriptors
4038 for reading symbols from object files and libraries. This was
4039 especially a problem for programs that used many (~100) shared
4042 The `step' command now only enters a subroutine if there is line number
4043 information for the subroutine. Otherwise it acts like the `next'
4044 command. Previously, `step' would enter subroutines if there was
4045 any debugging information about the routine. This avoids problems
4046 when using `cc -g1' on MIPS machines.
4048 * Internal improvements
4050 GDB's internal interfaces have been improved to make it easier to support
4051 debugging of multiple languages in the future.
4053 GDB now uses a common structure for symbol information internally.
4054 Minimal symbols (derived from linkage symbols in object files), partial
4055 symbols (from a quick scan of debug information), and full symbols
4056 contain a common subset of information, making it easier to write
4057 shared code that handles any of them.
4059 * New command line options
4061 We now accept --silent as an alias for --quiet.
4065 The memory-mapped-malloc library is now licensed under the GNU Library
4066 General Public License.
4068 *** Changes in GDB-4.7:
4070 * Host/native/target split
4072 GDB has had some major internal surgery to untangle the support for
4073 hosts and remote targets. Now, when you configure GDB for a remote
4074 target, it will no longer load in all of the support for debugging
4075 local programs on the host. When fully completed and tested, this will
4076 ensure that arbitrary host/target combinations are possible.
4078 The primary conceptual shift is to separate the non-portable code in
4079 GDB into three categories. Host specific code is required any time GDB
4080 is compiled on that host, regardless of the target. Target specific
4081 code relates to the peculiarities of the target, but can be compiled on
4082 any host. Native specific code is everything else: it can only be
4083 built when the host and target are the same system. Child process
4084 handling and core file support are two common `native' examples.
4086 GDB's use of /proc for controlling Unix child processes is now cleaner.
4087 It has been split out into a single module under the `target_ops' vector,
4088 plus two native-dependent functions for each system that uses /proc.
4090 * New hosts supported
4092 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4093 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4094 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4096 * New targets supported
4098 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4099 68030 and CPU32 m68030-*-*, m68332-*-*
4101 * New native hosts supported
4103 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4104 (386bsd is not well tested yet)
4105 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4107 * New file formats supported
4109 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4110 supports reading of `a.out.adobe' object files, which are an a.out
4111 format extended with minimal information about multiple sections.
4115 `show copying' is the same as the old `info copying'.
4116 `show warranty' is the same as `info warrantee'.
4117 These were renamed for consistency. The old commands continue to work.
4119 `info handle' is a new alias for `info signals'.
4121 You can now define pre-command hooks, which attach arbitrary command
4122 scripts to any command. The commands in the hook will be executed
4123 prior to the user's command. You can also create a hook which will be
4124 executed whenever the program stops. See gdb.texinfo.
4128 We now deal with Cfront style name mangling, and can even extract type
4129 info from mangled symbols. GDB can automatically figure out which
4130 symbol mangling style your C++ compiler uses.
4132 Calling of methods and virtual functions has been improved as well.
4136 The crash that occured when debugging Sun Ansi-C compiled binaries is
4137 fixed. This was due to mishandling of the extra N_SO stabs output
4140 We also finally got Ultrix 4.2 running in house, and fixed core file
4141 support, with help from a dozen people on the net.
4143 John M. Farrell discovered that the reason that single-stepping was so
4144 slow on all of the Mips based platforms (primarily SGI and DEC) was
4145 that we were trying to demangle and lookup a symbol used for internal
4146 purposes on every instruction that was being stepped through. Changing
4147 the name of that symbol so that it couldn't be mistaken for a C++
4148 mangled symbol sped things up a great deal.
4150 Rich Pixley sped up symbol lookups in general by getting much smarter
4151 about when C++ symbol mangling is necessary. This should make symbol
4152 completion (TAB on the command line) much faster. It's not as fast as
4153 we'd like, but it's significantly faster than gdb-4.6.
4157 A new user controllable variable 'call_scratch_address' can
4158 specify the location of a scratch area to be used when GDB
4159 calls a function in the target. This is necessary because the
4160 usual method of putting the scratch area on the stack does not work
4161 in systems that have separate instruction and data spaces.
4163 We integrated changes to support the 29k UDI (Universal Debugger
4164 Interface), but discovered at the last minute that we didn't have all
4165 of the appropriate copyright paperwork. We are working with AMD to
4166 resolve this, and hope to have it available soon.
4170 We have sped up the remote serial line protocol, especially for targets
4171 with lots of registers. It now supports a new `expedited status' ('T')
4172 message which can be used in place of the existing 'S' status message.
4173 This allows the remote stub to send only the registers that GDB
4174 needs to make a quick decision about single-stepping or conditional
4175 breakpoints, eliminating the need to fetch the entire register set for
4176 each instruction being stepped through.
4178 The GDB remote serial protocol now implements a write-through cache for
4179 registers, only re-reading the registers if the target has run.
4181 There is also a new remote serial stub for SPARC processors. You can
4182 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4183 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4184 processor with a serial port.
4188 Configure.in files have become much easier to read and modify. A new
4189 `table driven' format makes it more obvious what configurations are
4190 supported, and what files each one uses.
4194 There is a new opcodes library which will eventually contain all of the
4195 disassembly routines and opcode tables. At present, it only contains
4196 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4197 disassembler (binutils/objdump) to share these routines.
4199 The libiberty library is now copylefted under the GNU Library General
4200 Public License. This allows more liberal use, and was done so libg++
4201 can use it. This makes no difference to GDB, since the Library License
4202 grants all the rights from the General Public License.
4206 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4207 reference to the stabs symbol info used by the debugger. It is (as far
4208 as we know) the only published document on this fascinating topic. We
4209 encourage you to read it, compare it to the stabs information on your
4210 system, and send improvements on the document in general (to
4211 bug-gdb@prep.ai.mit.edu).
4213 And, of course, many bugs have been fixed.
4216 *** Changes in GDB-4.6:
4218 * Better support for C++ function names
4220 GDB now accepts as input the "demangled form" of C++ overloaded function
4221 names and member function names, and can do command completion on such names
4222 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4223 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4224 Make use of command completion, it is your friend.
4226 GDB also now accepts a variety of C++ mangled symbol formats. They are
4227 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4228 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4229 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4230 for the list of formats.
4232 * G++ symbol mangling problem
4234 Recent versions of gcc have a bug in how they emit debugging information for
4235 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4236 directory) can be applied to gcc to fix the problem. Alternatively, if you
4237 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4238 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4239 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4242 * New 'maintenance' command
4244 All of the commands related to hacking GDB internals have been moved out of
4245 the main command set, and now live behind the 'maintenance' command. This
4246 can also be abbreviated as 'mt'. The following changes were made:
4248 dump-me -> maintenance dump-me
4249 info all-breakpoints -> maintenance info breakpoints
4250 printmsyms -> maintenance print msyms
4251 printobjfiles -> maintenance print objfiles
4252 printpsyms -> maintenance print psymbols
4253 printsyms -> maintenance print symbols
4255 The following commands are new:
4257 maintenance demangle Call internal GDB demangler routine to
4258 demangle a C++ link name and prints the result.
4259 maintenance print type Print a type chain for a given symbol
4261 * Change to .gdbinit file processing
4263 We now read the $HOME/.gdbinit file before processing the argv arguments
4264 (e.g. reading symbol files or core files). This allows global parameters to
4265 be set, which will apply during the symbol reading. The ./.gdbinit is still
4266 read after argv processing.
4268 * New hosts supported
4270 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4272 GNU/Linux support i386-unknown-linux or linux
4274 We are also including code to support the HP/PA running BSD and HPUX. This
4275 is almost guaranteed not to work, as we didn't have time to test or build it
4276 for this release. We are including it so that the more adventurous (or
4277 masochistic) of you can play with it. We also had major problems with the
4278 fact that the compiler that we got from HP doesn't support the -g option.
4281 * New targets supported
4283 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4285 * More smarts about finding #include files
4287 GDB now remembers the compilation directory for all include files, and for
4288 all files from which C is generated (like yacc and lex sources). This
4289 greatly improves GDB's ability to find yacc/lex sources, and include files,
4290 especially if you are debugging your program from a directory different from
4291 the one that contains your sources.
4293 We also fixed a bug which caused difficulty with listing and setting
4294 breakpoints in include files which contain C code. (In the past, you had to
4295 try twice in order to list an include file that you hadn't looked at before.)
4297 * Interesting infernals change
4299 GDB now deals with arbitrary numbers of sections, where the symbols for each
4300 section must be relocated relative to that section's landing place in the
4301 target's address space. This work was needed to support ELF with embedded
4302 stabs used by Solaris-2.0.
4304 * Bug fixes (of course!)
4306 There have been loads of fixes for the following things:
4307 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4308 i960, stabs, DOS(GO32), procfs, etc...
4310 See the ChangeLog for details.
4312 *** Changes in GDB-4.5:
4314 * New machines supported (host and target)
4316 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4318 SGI Irix-4.x mips-sgi-irix4 or iris4
4320 * New malloc package
4322 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4323 Mmalloc is capable of handling mutiple heaps of memory. It is also
4324 capable of saving a heap to a file, and then mapping it back in later.
4325 This can be used to greatly speedup the startup of GDB by using a
4326 pre-parsed symbol table which lives in a mmalloc managed heap. For
4327 more details, please read mmalloc/mmalloc.texi.
4331 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4332 'help info proc' for details.
4334 * MIPS ecoff symbol table format
4336 The code that reads MIPS symbol table format is now supported on all hosts.
4337 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4340 * File name changes for MS-DOS
4342 Many files in the config directories have been renamed to make it easier to
4343 support GDB on MS-DOSe systems (which have very restrictive file name
4344 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4345 environment) is close to working but has some remaining problems. Note
4346 that debugging of DOS programs is not supported, due to limitations
4347 in the ``operating system'', but it can be used to host cross-debugging.
4349 * Cross byte order fixes
4351 Many fixes have been made to support cross debugging of Sparc and MIPS
4352 targets from hosts whose byte order differs.
4354 * New -mapped and -readnow options
4356 If memory-mapped files are available on your system through the 'mmap'
4357 system call, you can use the -mapped option on the `file' or
4358 `symbol-file' commands to cause GDB to write the symbols from your
4359 program into a reusable file. If the program you are debugging is
4360 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4361 Future GDB debugging sessions will notice the presence of this file,
4362 and will quickly map in symbol information from it, rather than reading
4363 the symbol table from the executable program. Using the '-mapped'
4364 option in a GDB `file' or `symbol-file' command has the same effect as
4365 starting GDB with the '-mapped' command-line option.
4367 You can cause GDB to read the entire symbol table immediately by using
4368 the '-readnow' option with any of the commands that load symbol table
4369 information (or on the GDB command line). This makes the command
4370 slower, but makes future operations faster.
4372 The -mapped and -readnow options are typically combined in order to
4373 build a `fred.syms' file that contains complete symbol information.
4374 A simple GDB invocation to do nothing but build a `.syms' file for future
4377 gdb -batch -nx -mapped -readnow programname
4379 The `.syms' file is specific to the host machine on which GDB is run.
4380 It holds an exact image of GDB's internal symbol table. It cannot be
4381 shared across multiple host platforms.
4383 * longjmp() handling
4385 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4386 siglongjmp() without losing control. This feature has not yet been ported to
4387 all systems. It currently works on many 386 platforms, all MIPS-based
4388 platforms (SGI, DECstation, etc), and Sun3/4.
4392 Preliminary work has been put in to support the new Solaris OS from Sun. At
4393 this time, it can control and debug processes, but it is not capable of
4398 As always, many many bug fixes. The major areas were with g++, and mipsread.
4399 People using the MIPS-based platforms should experience fewer mysterious
4400 crashes and trashed symbol tables.
4402 *** Changes in GDB-4.4:
4404 * New machines supported (host and target)
4406 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4408 BSD Reno on Vax vax-dec-bsd
4409 Ultrix on Vax vax-dec-ultrix
4411 * New machines supported (target)
4413 AMD 29000 embedded, using EBMON a29k-none-none
4417 GDB continues to improve its handling of C++. `References' work better.
4418 The demangler has also been improved, and now deals with symbols mangled as
4419 per the Annotated C++ Reference Guide.
4421 GDB also now handles `stabs' symbol information embedded in MIPS
4422 `ecoff' symbol tables. Since the ecoff format was not easily
4423 extensible to handle new languages such as C++, this appeared to be a
4424 good way to put C++ debugging info into MIPS binaries. This option
4425 will be supported in the GNU C compiler, version 2, when it is
4428 * New features for SVR4
4430 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4431 shared libraries. Debugging dynamically linked programs should present
4432 only minor differences from debugging statically linked programs.
4434 The `info proc' command will print out information about any process
4435 on an SVR4 system (including the one you are debugging). At the moment,
4436 it prints the address mappings of the process.
4438 If you bring up GDB on another SVR4 system, please send mail to
4439 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4441 * Better dynamic linking support in SunOS
4443 Reading symbols from shared libraries which contain debugging symbols
4444 now works properly. However, there remain issues such as automatic
4445 skipping of `transfer vector' code during function calls, which
4446 make it harder to debug code in a shared library, than to debug the
4447 same code linked statically.
4451 GDB is now using the latest `getopt' routines from the FSF. This
4452 version accepts the -- prefix for options with long names. GDB will
4453 continue to accept the old forms (-option and +option) as well.
4454 Various single letter abbreviations for options have been explicity
4455 added to the option table so that they won't get overshadowed in the
4456 future by other options that begin with the same letter.
4460 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4461 Many assorted bugs have been handled. Many more remain to be handled.
4462 See the various ChangeLog files (primarily in gdb and bfd) for details.
4465 *** Changes in GDB-4.3:
4467 * New machines supported (host and target)
4469 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4470 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4471 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4473 * Almost SCO Unix support
4475 We had hoped to support:
4476 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4477 (except for core file support), but we discovered very late in the release
4478 that it has problems with process groups that render gdb unusable. Sorry
4479 about that. I encourage people to fix it and post the fixes.
4481 * Preliminary ELF and DWARF support
4483 GDB can read ELF object files on System V Release 4, and can handle
4484 debugging records for C, in DWARF format, in ELF files. This support
4485 is preliminary. If you bring up GDB on another SVR4 system, please
4486 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4491 GDB now uses the latest `readline' library. One user-visible change
4492 is that two tabs will list possible command completions, which previously
4493 required typing M-? (meta-question mark, or ESC ?).
4497 The `stepi' bug that many of you noticed has been squashed.
4498 Many bugs in C++ have been handled. Many more remain to be handled.
4499 See the various ChangeLog files (primarily in gdb and bfd) for details.
4501 * State of the MIPS world (in case you wondered):
4503 GDB can understand the symbol tables emitted by the compilers
4504 supplied by most vendors of MIPS-based machines, including DEC. These
4505 symbol tables are in a format that essentially nobody else uses.
4507 Some versions of gcc come with an assembler post-processor called
4508 mips-tfile. This program is required if you want to do source-level
4509 debugging of gcc-compiled programs. I believe FSF does not ship
4510 mips-tfile with gcc version 1, but it will eventually come with gcc
4513 Debugging of g++ output remains a problem. g++ version 1.xx does not
4514 really support it at all. (If you're lucky, you should be able to get
4515 line numbers and stack traces to work, but no parameters or local
4516 variables.) With some work it should be possible to improve the
4519 When gcc version 2 is released, you will have somewhat better luck.
4520 However, even then you will get confusing results for inheritance and
4523 We will eventually provide full debugging of g++ output on
4524 DECstations. This will probably involve some kind of stabs-in-ecoff
4525 encapulation, but the details have not been worked out yet.
4528 *** Changes in GDB-4.2:
4530 * Improved configuration
4532 Only one copy of `configure' exists now, and it is not self-modifying.
4533 Porting BFD is simpler.
4537 The `step' and `next' commands now only stop at the first instruction
4538 of a source line. This prevents the multiple stops that used to occur
4539 in switch statements, for-loops, etc. `Step' continues to stop if a
4540 function that has debugging information is called within the line.
4544 Lots of small bugs fixed. More remain.
4546 * New host supported (not target)
4548 Intel 386 PC clone running Mach i386-none-mach
4551 *** Changes in GDB-4.1:
4553 * Multiple source language support
4555 GDB now has internal scaffolding to handle several source languages.
4556 It determines the type of each source file from its filename extension,
4557 and will switch expression parsing and number formatting to match the
4558 language of the function in the currently selected stack frame.
4559 You can also specifically set the language to be used, with
4560 `set language c' or `set language modula-2'.
4564 GDB now has preliminary support for the GNU Modula-2 compiler,
4565 currently under development at the State University of New York at
4566 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4567 continue through the fall of 1991 and into 1992.
4569 Other Modula-2 compilers are currently not supported, and attempting to
4570 debug programs compiled with them will likely result in an error as the
4571 symbol table is read. Feel free to work on it, though!
4573 There are hooks in GDB for strict type checking and range checking,
4574 in the `Modula-2 philosophy', but they do not currently work.
4578 GDB can now write to executable and core files (e.g. patch
4579 a variable's value). You must turn this switch on, specify
4580 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4581 by assigning a new value to a variable. Modifications take
4584 * Automatic SunOS shared library reading
4586 When you run your program, GDB automatically determines where its
4587 shared libraries (if any) have been loaded, and reads their symbols.
4588 The `share' command is no longer needed. This also works when
4589 examining core files.
4593 You can specify the number of lines that the `list' command shows.
4596 * New machines supported (host and target)
4598 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4599 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4600 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4602 * New hosts supported (not targets)
4604 IBM RT/PC: romp-ibm-aix or rtpc
4606 * New targets supported (not hosts)
4608 AMD 29000 embedded with COFF a29k-none-coff
4609 AMD 29000 embedded with a.out a29k-none-aout
4610 Ultracomputer remote kernel debug a29k-nyu-kern
4612 * New remote interfaces
4618 *** Changes in GDB-4.0:
4622 Wide output is wrapped at good places to make the output more readable.
4624 Gdb now supports cross-debugging from a host machine of one type to a
4625 target machine of another type. Communication with the target system
4626 is over serial lines. The ``target'' command handles connecting to the
4627 remote system; the ``load'' command will download a program into the
4628 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4629 also supports debugging of realtime processes running under VxWorks,
4630 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4631 stub on the target system.
4633 New CPUs supported include the AMD 29000 and Intel 960.
4635 GDB now reads object files and symbol tables via a ``binary file''
4636 library, which allows a single copy of GDB to debug programs of multiple
4637 object file types such as a.out and coff.
4639 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4640 refcard.dvi and refcard.ps are available to format it).
4643 * Control-Variable user interface simplified
4645 All variables that control the operation of the debugger can be set
4646 by the ``set'' command, and displayed by the ``show'' command.
4648 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4649 ``Show prompt'' produces the response:
4650 Gdb's prompt is new-gdb=>.
4652 What follows are the NEW set commands. The command ``help set'' will
4653 print a complete list of old and new set commands. ``help set FOO''
4654 will give a longer description of the variable FOO. ``show'' will show
4655 all of the variable descriptions and their current settings.
4657 confirm on/off: Enables warning questions for operations that are
4658 hard to recover from, e.g. rerunning the program while
4659 it is already running. Default is ON.
4661 editing on/off: Enables EMACS style command line editing
4662 of input. Previous lines can be recalled with
4663 control-P, the current line can be edited with control-B,
4664 you can search for commands with control-R, etc.
4667 history filename NAME: NAME is where the gdb command history
4668 will be stored. The default is .gdb_history,
4669 or the value of the environment variable
4672 history size N: The size, in commands, of the command history. The
4673 default is 256, or the value of the environment variable
4676 history save on/off: If this value is set to ON, the history file will
4677 be saved after exiting gdb. If set to OFF, the
4678 file will not be saved. The default is OFF.
4680 history expansion on/off: If this value is set to ON, then csh-like
4681 history expansion will be performed on
4682 command line input. The default is OFF.
4684 radix N: Sets the default radix for input and output. It can be set
4685 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4686 in the current radix, so "set radix 10" is always a no-op.
4688 height N: This integer value is the number of lines on a page. Default
4689 is 24, the current `stty rows'' setting, or the ``li#''
4690 setting from the termcap entry matching the environment
4693 width N: This integer value is the number of characters on a line.
4694 Default is 80, the current `stty cols'' setting, or the ``co#''
4695 setting from the termcap entry matching the environment
4698 Note: ``set screensize'' is obsolete. Use ``set height'' and
4699 ``set width'' instead.
4701 print address on/off: Print memory addresses in various command displays,
4702 such as stack traces and structure values. Gdb looks
4703 more ``symbolic'' if you turn this off; it looks more
4704 ``machine level'' with it on. Default is ON.
4706 print array on/off: Prettyprint arrays. New convenient format! Default
4709 print demangle on/off: Print C++ symbols in "source" form if on,
4712 print asm-demangle on/off: Same, for assembler level printouts
4715 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4718 * Support for Epoch Environment.
4720 The epoch environment is a version of Emacs v18 with windowing. One
4721 new command, ``inspect'', is identical to ``print'', except that if you
4722 are running in the epoch environment, the value is printed in its own
4726 * Support for Shared Libraries
4728 GDB can now debug programs and core files that use SunOS shared libraries.
4729 Symbols from a shared library cannot be referenced
4730 before the shared library has been linked with the program (this
4731 happens after you type ``run'' and before the function main() is entered).
4732 At any time after this linking (including when examining core files
4733 from dynamically linked programs), gdb reads the symbols from each
4734 shared library when you type the ``sharedlibrary'' command.
4735 It can be abbreviated ``share''.
4737 sharedlibrary REGEXP: Load shared object library symbols for files
4738 matching a unix regular expression. No argument
4739 indicates to load symbols for all shared libraries.
4741 info sharedlibrary: Status of loaded shared libraries.
4746 A watchpoint stops execution of a program whenever the value of an
4747 expression changes. Checking for this slows down execution
4748 tremendously whenever you are in the scope of the expression, but is
4749 quite useful for catching tough ``bit-spreader'' or pointer misuse
4750 problems. Some machines such as the 386 have hardware for doing this
4751 more quickly, and future versions of gdb will use this hardware.
4753 watch EXP: Set a watchpoint (breakpoint) for an expression.
4755 info watchpoints: Information about your watchpoints.
4757 delete N: Deletes watchpoint number N (same as breakpoints).
4758 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4759 enable N: Re-enables watchpoint number N (same as breakpoints).
4762 * C++ multiple inheritance
4764 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4767 * C++ exception handling
4769 Gdb now supports limited C++ exception handling. Besides the existing
4770 ability to breakpoint on an exception handler, gdb can breakpoint on
4771 the raising of an exception (before the stack is peeled back to the
4774 catch FOO: If there is a FOO exception handler in the dynamic scope,
4775 set a breakpoint to catch exceptions which may be raised there.
4776 Multiple exceptions (``catch foo bar baz'') may be caught.
4778 info catch: Lists all exceptions which may be caught in the
4779 current stack frame.
4782 * Minor command changes
4784 The command ``call func (arg, arg, ...)'' now acts like the print
4785 command, except it does not print or save a value if the function's result
4786 is void. This is similar to dbx usage.
4788 The ``up'' and ``down'' commands now always print the frame they end up
4789 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4790 frames without printing.
4792 * New directory command
4794 'dir' now adds directories to the FRONT of the source search path.
4795 The path starts off empty. Source files that contain debug information
4796 about the directory in which they were compiled can be found even
4797 with an empty path; Sun CC and GCC include this information. If GDB can't
4798 find your source file in the current directory, type "dir .".
4800 * Configuring GDB for compilation
4802 For normal use, type ``./configure host''. See README or gdb.texinfo
4805 GDB now handles cross debugging. If you are remotely debugging between
4806 two different machines, type ``./configure host -target=targ''.
4807 Host is the machine where GDB will run; targ is the machine
4808 where the program that you are debugging will run.