1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.4
6 * The option "symbol-reloading" has been deleted as it is no longer used.
10 ** GDB commands implemented in Python can now be put in command class
13 ** The "maint set python print-stack on|off" is now deleted.
15 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
16 apply "flag enum"-style pretty-printing to any enum.
18 ** gdb.lookup_symbol can now work when there is no current frame.
20 ** gdb.Symbol now has a 'line' attribute, holding the line number in
21 the source at which the symbol was defined.
23 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
24 method 'value'. The former indicates whether the symbol needs a
25 frame in order to compute its value, and the latter computes the
28 * GDBserver now supports stdio connections.
29 E.g. (gdb) target remote | ssh myhost gdbserver - hello
31 * The binary "gdbtui" can no longer be built or installed.
32 Use "gdb -tui" instead.
34 * GDB will now print "flag" enums specially. A flag enum is one where
35 all the enumerator values have no bits in common when pairwise
36 "and"ed. When printing a value whose type is a flag enum, GDB will
37 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
38 (gdb) print (enum E) 3
41 * The filename part of a linespec will now match trailing components
42 of a source file name. For example, "break gcc/expr.c:1000" will
43 now set a breakpoint in build/gcc/expr.c, but not
46 * The "info proc" and "generate-core-file" commands will now also
47 work on remote targets connected to GDBserver on Linux.
49 * The command "info catch" has been removed. It has been disabled
52 * The "catch exception" and "catch assert" commands now accept
53 a condition at the end of the command, much like the "break"
54 command does. For instance:
56 (gdb) catch exception Constraint_Error if Barrier = True
58 Previously, it was possible to add a condition to such catchpoints,
59 but it had to be done as a second step, after the catchpoint had been
60 created, using the "condition" command.
62 * The "info static-tracepoint-marker" command will now also work on
63 native Linux targets with in-process agent.
67 ** "catch load" and "catch unload" can be used to stop when a shared
68 library is loaded or unloaded, respectively.
70 ** "enable count" can be used to auto-disable a breakpoint after
75 Renesas RL78 rl78-*-elf
76 HP OpenVMS ia64 ia64-hp-openvms*
78 * GDBserver supports evaluation of breakpoint conditions. When
79 support is advertised by GDBserver, GDB may be told to send the
80 breakpoint conditions in bytecode form to GDBserver. GDBserver
81 will only report the breakpoint trigger to GDB when its condition
86 set breakpoint condition-evaluation
87 show breakpoint condition-evaluation
88 Controls whether breakpoint conditions are evaluated by GDB ("gdb") or by
90 This option can improve debugger efficiency depending on the speed of the
95 z0/z1 conditional breakpoints extension
97 The z0/z1 breakpoint insertion packets have been extended to carry
98 a list of conditional expressions over to the remote stub depending on the
99 condition evaluation mode. The use of this extension can be controlled
100 via the "set remote conditional-breakpoints-packet" command.
104 Specify the signals which the remote stub may pass to the debugged
105 program without GDB involvement.
107 *** Changes in GDB 7.4
109 * GDB now handles ambiguous linespecs more consistently; the existing
110 FILE:LINE support has been expanded to other types of linespecs. A
111 breakpoint will now be set on all matching locations in all
112 inferiors, and locations will be added or removed according to
115 * GDB now allows you to skip uninteresting functions and files when
116 stepping with the "skip function" and "skip file" commands.
118 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
119 and "show remote hardware-watchpoint-length-limit". These allows to
120 set or show the maximum length limit (in bytes) of a remote
121 target hardware watchpoint.
123 This allows e.g. to use "unlimited" hardware watchpoints with the
124 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
125 watchpoints are slower than real hardware watchpoints but are
126 significantly faster than gdb software watchpoints.
130 ** The register_pretty_printer function in module gdb.printing now takes
131 an optional `replace' argument. If True, the new printer replaces any
134 ** The "maint set python print-stack on|off" command has been
135 deprecated and will be deleted in GDB 7.5.
136 A new command: "set python print-stack none|full|message" has
137 replaced it. Additionally, the default for "print-stack" is
138 now "message", which just prints the error message without
141 ** A prompt substitution hook (prompt_hook) is now available to the
144 ** A new Python module, gdb.prompt has been added to the GDB Python
145 modules library. This module provides functionality for
146 escape sequences in prompts (used by set/show
147 extended-prompt). These escape sequences are replaced by their
150 ** Python commands and convenience-functions located in
151 'data-directory'/python/gdb/command and
152 'data-directory'/python/gdb/function are now automatically loaded
155 ** Blocks now provide four new attributes. global_block and
156 static_block will return the global and static blocks
157 respectively. is_static and is_global are boolean attributes
158 that indicate if the block is one of those two types.
160 ** Symbols now provide the "type" attribute, the type of the symbol.
162 ** The "gdb.breakpoint" function has been deprecated in favor of
165 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
166 of a function. This class is based on the "finish" command
167 available in the CLI.
169 ** Type objects for struct and union types now allow access to
170 the fields using standard Python dictionary (mapping) methods.
171 For example, "some_type['myfield']" now works, as does
174 ** A new event "gdb.new_objfile" has been added, triggered by loading a
177 ** A new function, "deep_items" has been added to the gdb.types
178 module in the GDB Python modules library. This function returns
179 an iterator over the fields of a struct or union type. Unlike
180 the standard Python "iteritems" method, it will recursively traverse
181 any anonymous fields.
185 ** "*stopped" events can report several new "reason"s, such as
188 ** Breakpoint changes are now notified using new async records, like
189 "=breakpoint-modified".
191 ** New command -ada-task-info.
193 * libthread-db-search-path now supports two special values: $sdir and $pdir.
194 $sdir specifies the default system locations of shared libraries.
195 $pdir specifies the directory where the libpthread used by the application
198 GDB no longer looks in $sdir and $pdir after it has searched the directories
199 mentioned in libthread-db-search-path. If you want to search those
200 directories, they must be specified in libthread-db-search-path.
201 The default value of libthread-db-search-path on GNU/Linux and Solaris
202 systems is now "$sdir:$pdir".
204 $pdir is not supported by gdbserver, it is currently ignored.
205 $sdir is supported by gdbserver.
207 * New configure option --with-iconv-bin.
208 When using the internationalization support like the one in the GNU C
209 library, GDB will invoke the "iconv" program to get a list of supported
210 character sets. If this program lives in a non-standard location, one can
211 use this option to specify where to find it.
213 * When natively debugging programs on PowerPC BookE processors running
214 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
215 watchpoints, which specify a mask in addition to an address to watch.
216 The mask specifies that some bits of an address (the bits which are
217 reset in the mask) should be ignored when matching the address accessed
218 by the inferior against the watchpoint address. See the "PowerPC Embedded"
219 section in the user manual for more details.
221 * The new option --once causes GDBserver to stop listening for connections once
222 the first connection is made. The listening port used by GDBserver will
223 become available after that.
225 * New commands "info macros" and "alias" have been added.
227 * New function parameters suffix @entry specifies value of function parameter
228 at the time the function got called. Entry values are available only since
234 "!" is now an alias of the "shell" command.
235 Note that no space is needed between "!" and SHELL COMMAND.
239 watch EXPRESSION mask MASK_VALUE
240 The watch command now supports the mask argument which allows creation
241 of masked watchpoints, if the current architecture supports this feature.
243 info auto-load-scripts [REGEXP]
244 This command was formerly named "maintenance print section-scripts".
245 It is now generally useful and is no longer a maintenance-only command.
247 info macro [-all] [--] MACRO
248 The info macro command has new options `-all' and `--'. The first for
249 printing all definitions of a macro. The second for explicitly specifying
250 the end of arguments and the beginning of the macro name in case the macro
251 name starts with a hyphen.
253 collect[/s] EXPRESSIONS
254 The tracepoint collect command now takes an optional modifier "/s"
255 that directs it to dereference pointer-to-character types and
256 collect the bytes of memory up to a zero byte. The behavior is
257 similar to what you see when you use the regular print command on a
258 string. An optional integer following the "/s" sets a bound on the
259 number of bytes that will be collected.
262 The trace start command now interprets any supplied arguments as a
263 note to be recorded with the trace run, with an effect similar to
264 setting the variable trace-notes.
267 The trace stop command now interprets any arguments as a note to be
268 mentioned along with the tstatus report that the trace was stopped
269 with a command. The effect is similar to setting the variable
272 * Tracepoints can now be enabled and disabled at any time after a trace
273 experiment has been started using the standard "enable" and "disable"
274 commands. It is now possible to start a trace experiment with no enabled
275 tracepoints; GDB will display a warning, but will allow the experiment to
276 begin, assuming that tracepoints will be enabled as needed while the trace
279 * Fast tracepoints on 32-bit x86-architectures can now be placed at
280 locations with 4-byte instructions, when they were previously
281 limited to locations with instructions of 5 bytes or longer.
287 Set the GDB prompt, and allow escape sequences to be inserted to
288 display miscellaneous information (see 'help set extended-prompt'
289 for the list of sequences). This prompt (and any information
290 accessed through the escape sequences) is updated every time the
293 set print entry-values (both|compact|default|if-needed|no|only|preferred)
294 show print entry-values
295 Set printing of frame argument values at function entry. In some cases
296 GDB can determine the value of function argument which was passed by the
297 function caller, even if the value was modified inside the called function.
299 set debug entry-values
300 show debug entry-values
301 Control display of debugging info for determining frame argument values at
302 function entry and virtual tail call frames.
304 set basenames-may-differ
305 show basenames-may-differ
306 Set whether a source file may have multiple base names.
307 (A "base name" is the name of a file with the directory part removed.
308 Example: The base name of "/home/user/hello.c" is "hello.c".)
309 If set, GDB will canonicalize file names (e.g., expand symlinks)
310 before comparing them. Canonicalization is an expensive operation,
311 but it allows the same file be known by more than one base name.
312 If not set (the default), all source files are assumed to have just
313 one base name, and gdb will do file name comparisons more efficiently.
319 Set a user name and notes for the current and any future trace runs.
320 This is useful for long-running and/or disconnected traces, to
321 inform others (or yourself) as to who is running the trace, supply
322 contact information, or otherwise explain what is going on.
325 show trace-stop-notes
326 Set a note attached to the trace run, that is displayed when the
327 trace has been stopped by a tstop command. This is useful for
328 instance as an explanation, if you are stopping a trace run that was
329 started by someone else.
335 Dynamically enable a tracepoint in a started trace experiment.
339 Dynamically disable a tracepoint in a started trace experiment.
343 Set the user and notes of the trace run.
347 Query the current status of a tracepoint.
351 Query the minimum length of instruction at which a fast tracepoint may
354 * Dcache size (number of lines) and line-size are now runtime-configurable
355 via "set dcache line" and "set dcache line-size" commands.
359 Texas Instruments TMS320C6x tic6x-*-*
363 Renesas RL78 rl78-*-elf
365 *** Changes in GDB 7.3.1
367 * The build failure for NetBSD and OpenBSD targets have now been fixed.
369 *** Changes in GDB 7.3
371 * GDB has a new command: "thread find [REGEXP]".
372 It finds the thread id whose name, target id, or thread extra info
373 matches the given regular expression.
375 * The "catch syscall" command now works on mips*-linux* targets.
377 * The -data-disassemble MI command now supports modes 2 and 3 for
378 dumping the instruction opcodes.
380 * New command line options
382 -data-directory DIR Specify DIR as the "data-directory".
383 This is mostly for testing purposes.
385 * The "maint set python auto-load on|off" command has been renamed to
386 "set auto-load-scripts on|off".
388 * GDB has a new command: "set directories".
389 It is like the "dir" command except that it replaces the
390 source path list instead of augmenting it.
392 * GDB now understands thread names.
394 On GNU/Linux, "info threads" will display the thread name as set by
395 prctl or pthread_setname_np.
397 There is also a new command, "thread name", which can be used to
398 assign a name internally for GDB to display.
401 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
402 has been integrated into GDB.
406 ** The function gdb.Write now accepts an optional keyword 'stream'.
407 This keyword, when provided, will direct the output to either
408 stdout, stderr, or GDB's logging output.
410 ** Parameters can now be be sub-classed in Python, and in particular
411 you may implement the get_set_doc and get_show_doc functions.
412 This improves how Parameter set/show documentation is processed
413 and allows for more dynamic content.
415 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
416 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
417 have an is_valid method.
419 ** Breakpoints can now be sub-classed in Python, and in particular
420 you may implement a 'stop' function that is executed each time
421 the inferior reaches that breakpoint.
423 ** New function gdb.lookup_global_symbol looks up a global symbol.
425 ** GDB values in Python are now callable if the value represents a
426 function. For example, if 'some_value' represents a function that
427 takes two integer parameters and returns a value, you can call
428 that function like so:
430 result = some_value (10,20)
432 ** Module gdb.types has been added.
433 It contains a collection of utilities for working with gdb.Types objects:
434 get_basic_type, has_field, make_enum_dict.
436 ** Module gdb.printing has been added.
437 It contains utilities for writing and registering pretty-printers.
438 New classes: PrettyPrinter, SubPrettyPrinter,
439 RegexpCollectionPrettyPrinter.
440 New function: register_pretty_printer.
442 ** New commands "info pretty-printers", "enable pretty-printer" and
443 "disable pretty-printer" have been added.
445 ** gdb.parameter("directories") is now available.
447 ** New function gdb.newest_frame returns the newest frame in the
450 ** The gdb.InferiorThread class has a new "name" attribute. This
451 holds the thread's name.
453 ** Python Support for Inferior events.
454 Python scripts can add observers to be notified of events
455 occurring in the process being debugged.
456 The following events are currently supported:
457 - gdb.events.cont Continue event.
458 - gdb.events.exited Inferior exited event.
459 - gdb.events.stop Signal received, and Breakpoint hit events.
463 ** GDB now puts template parameters in scope when debugging in an
464 instantiation. For example, if you have:
466 template<int X> int func (void) { return X; }
468 then if you step into func<5>, "print X" will show "5". This
469 feature requires proper debuginfo support from the compiler; it
470 was added to GCC 4.5.
472 ** The motion commands "next", "finish", "until", and "advance" now
473 work better when exceptions are thrown. In particular, GDB will
474 no longer lose control of the inferior; instead, the GDB will
475 stop the inferior at the point at which the exception is caught.
476 This functionality requires a change in the exception handling
477 code that was introduced in GCC 4.5.
479 * GDB now follows GCC's rules on accessing volatile objects when
480 reading or writing target state during expression evaluation.
481 One notable difference to prior behavior is that "print x = 0"
482 no longer generates a read of x; the value of the assignment is
483 now always taken directly from the value being assigned.
485 * GDB now has some support for using labels in the program's source in
486 linespecs. For instance, you can use "advance label" to continue
487 execution to a label.
489 * GDB now has support for reading and writing a new .gdb_index
490 section. This section holds a fast index of DWARF debugging
491 information and can be used to greatly speed up GDB startup and
492 operation. See the documentation for `save gdb-index' for details.
494 * The "watch" command now accepts an optional "-location" argument.
495 When used, this causes GDB to watch the memory referred to by the
496 expression. Such a watchpoint is never deleted due to it going out
499 * GDB now supports thread debugging of core dumps on GNU/Linux.
501 GDB now activates thread debugging using the libthread_db library
502 when debugging GNU/Linux core dumps, similarly to when debugging
503 live processes. As a result, when debugging a core dump file, GDB
504 is now able to display pthread_t ids of threads. For example, "info
505 threads" shows the same output as when debugging the process when it
506 was live. In earlier releases, you'd see something like this:
509 * 1 LWP 6780 main () at main.c:10
511 While now you see this:
514 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
516 It is also now possible to inspect TLS variables when debugging core
519 When debugging a core dump generated on a machine other than the one
520 used to run GDB, you may need to point GDB at the correct
521 libthread_db library with the "set libthread-db-search-path"
522 command. See the user manual for more details on this command.
524 * When natively debugging programs on PowerPC BookE processors running
525 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
526 which stop execution of the inferior whenever it executes an instruction
527 at any address within the specified range. See the "PowerPC Embedded"
528 section in the user manual for more details.
530 * New features in the GDB remote stub, GDBserver
532 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
533 and i686 LynxOS (version 5.x).
535 ** GDBserver is now supported on Blackfin Linux.
537 * New native configurations
539 ia64 HP-UX ia64-*-hpux*
543 Analog Devices, Inc. Blackfin Processor bfin-*
545 * Ada task switching is now supported on sparc-elf targets when
546 debugging a program using the Ravenscar Profile. For more information,
547 see the "Tasking Support when using the Ravenscar Profile" section
548 in the GDB user manual.
550 * Guile support was removed.
552 * New features in the GNU simulator
554 ** The --map-info flag lists all known core mappings.
556 ** CFI flashes may be simulated via the "cfi" device.
558 *** Changes in GDB 7.2
560 * Shared library support for remote targets by default
562 When GDB is configured for a generic, non-OS specific target, like
563 for example, --target=arm-eabi or one of the many *-*-elf targets,
564 GDB now queries remote stubs for loaded shared libraries using the
565 `qXfer:libraries:read' packet. Previously, shared library support
566 was always disabled for such configurations.
570 ** Argument Dependent Lookup (ADL)
572 In C++ ADL lookup directs function search to the namespaces of its
573 arguments even if the namespace has not been imported.
583 Here the compiler will search for `foo' in the namespace of 'b'
584 and find A::foo. GDB now supports this. This construct is commonly
585 used in the Standard Template Library for operators.
587 ** Improved User Defined Operator Support
589 In addition to member operators, GDB now supports lookup of operators
590 defined in a namespace and imported with a `using' directive, operators
591 defined in the global scope, operators imported implicitly from an
592 anonymous namespace, and the ADL operators mentioned in the previous
594 GDB now also supports proper overload resolution for all the previously
595 mentioned flavors of operators.
597 ** static const class members
599 Printing of static const class members that are initialized in the
600 class definition has been fixed.
602 * Windows Thread Information Block access.
604 On Windows targets, GDB now supports displaying the Windows Thread
605 Information Block (TIB) structure. This structure is visible either
606 by using the new command `info w32 thread-information-block' or, by
607 dereferencing the new convenience variable named `$_tlb', a
608 thread-specific pointer to the TIB. This feature is also supported
609 when remote debugging using GDBserver.
613 Static tracepoints are calls in the user program into a tracing
614 library. One such library is a port of the LTTng kernel tracer to
615 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
616 When debugging with GDBserver, GDB now supports combining the GDB
617 tracepoint machinery with such libraries. For example: the user can
618 use GDB to probe a static tracepoint marker (a call from the user
619 program into the tracing library) with the new "strace" command (see
620 "New commands" below). This creates a "static tracepoint" in the
621 breakpoint list, that can be manipulated with the same feature set
622 as fast and regular tracepoints. E.g., collect registers, local and
623 global variables, collect trace state variables, and define
624 tracepoint conditions. In addition, the user can collect extra
625 static tracepoint marker specific data, by collecting the new
626 $_sdata internal variable. When analyzing the trace buffer, you can
627 inspect $_sdata like any other variable available to GDB. For more
628 information, see the "Tracepoints" chapter in GDB user manual. New
629 remote packets have been defined to support static tracepoints, see
630 the "New remote packets" section below.
632 * Better reconstruction of tracepoints after disconnected tracing
634 GDB will attempt to download the original source form of tracepoint
635 definitions when starting a trace run, and then will upload these
636 upon reconnection to the target, resulting in a more accurate
637 reconstruction of the tracepoints that are in use on the target.
641 You can now exercise direct control over the ways that GDB can
642 affect your program. For instance, you can disallow the setting of
643 breakpoints, so that the program can run continuously (assuming
644 non-stop mode). In addition, the "observer" variable is available
645 to switch all of the different controls; in observer mode, GDB
646 cannot affect the target's behavior at all, which is useful for
647 tasks like diagnosing live systems in the field.
649 * The new convenience variable $_thread holds the number of the
656 Return the address of the Windows Thread Information Block of a given thread.
660 In response to several of the tracepoint packets, the target may now
661 also respond with a number of intermediate `qRelocInsn' request
662 packets before the final result packet, to have GDB handle
663 relocating an instruction to execute at a different address. This
664 is particularly useful for stubs that support fast tracepoints. GDB
665 reports support for this feature in the qSupported packet.
669 List static tracepoint markers in the target program.
673 List static tracepoint markers at a given address in the target
676 qXfer:statictrace:read
678 Read the static trace data collected (by a `collect $_sdata'
679 tracepoint action). The remote stub reports support for this packet
680 to gdb's qSupported query.
684 Send the current settings of GDB's permission flags.
688 Send part of the source (textual) form of a tracepoint definition,
689 which includes location, conditional, and action list.
691 * The source command now accepts a -s option to force searching for the
692 script in the source search path even if the script name specifies
695 * New features in the GDB remote stub, GDBserver
697 - GDBserver now support tracepoints (including fast tracepoints, and
698 static tracepoints). The feature is currently supported by the
699 i386-linux and amd64-linux builds. See the "Tracepoints support
700 in gdbserver" section in the manual for more information.
702 GDBserver JIT compiles the tracepoint's conditional agent
703 expression bytecode into native code whenever possible for low
704 overhead dynamic tracepoints conditionals. For such tracepoints,
705 an expression that examines program state is evaluated when the
706 tracepoint is reached, in order to determine whether to capture
707 trace data. If the condition is simple and false, processing the
708 tracepoint finishes very quickly and no data is gathered.
710 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
711 for static tracepoints support.
713 - GDBserver now supports x86_64 Windows 64-bit debugging.
715 * GDB now sends xmlRegisters= in qSupported packet to indicate that
716 it understands register description.
718 * The --batch flag now disables pagination and queries.
720 * X86 general purpose registers
722 GDB now supports reading/writing byte, word and double-word x86
723 general purpose registers directly. This means you can use, say,
724 $ah or $ax to refer, respectively, to the byte register AH and
725 16-bit word register AX that are actually portions of the 32-bit
726 register EAX or 64-bit register RAX.
728 * The `commands' command now accepts a range of breakpoints to modify.
729 A plain `commands' following a command that creates multiple
730 breakpoints affects all the breakpoints set by that command. This
731 applies to breakpoints set by `rbreak', and also applies when a
732 single `break' command creates multiple breakpoints (e.g.,
733 breakpoints on overloaded c++ functions).
735 * The `rbreak' command now accepts a filename specification as part of
736 its argument, limiting the functions selected by the regex to those
737 in the specified file.
739 * Support for remote debugging Windows and SymbianOS shared libraries
740 from Unix hosts has been improved. Non Windows GDB builds now can
741 understand target reported file names that follow MS-DOS based file
742 system semantics, such as file names that include drive letters and
743 use the backslash character as directory separator. This makes it
744 possible to transparently use the "set sysroot" and "set
745 solib-search-path" on Unix hosts to point as host copies of the
746 target's shared libraries. See the new command "set
747 target-file-system-kind" described below, and the "Commands to
748 specify files" section in the user manual for more information.
752 eval template, expressions...
753 Convert the values of one or more expressions under the control
754 of the string template to a command line, and call it.
756 set target-file-system-kind unix|dos-based|auto
757 show target-file-system-kind
758 Set or show the assumed file system kind for target reported file
761 save breakpoints <filename>
762 Save all current breakpoint definitions to a file suitable for use
763 in a later debugging session. To read the saved breakpoint
764 definitions, use the `source' command.
766 `save tracepoints' is a new alias for `save-tracepoints'. The latter
769 info static-tracepoint-markers
770 Display information about static tracepoint markers in the target.
772 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
773 Define a static tracepoint by probing a marker at the given
774 function, line, address, or marker ID.
778 Enable and disable observer mode.
780 set may-write-registers on|off
781 set may-write-memory on|off
782 set may-insert-breakpoints on|off
783 set may-insert-tracepoints on|off
784 set may-insert-fast-tracepoints on|off
785 set may-interrupt on|off
786 Set individual permissions for GDB effects on the target. Note that
787 some of these settings can have undesirable or surprising
788 consequences, particularly when changed in the middle of a session.
789 For instance, disabling the writing of memory can prevent
790 breakpoints from being inserted, cause single-stepping to fail, or
791 even crash your program, if you disable after breakpoints have been
792 inserted. However, GDB should not crash.
794 set record memory-query on|off
795 show record memory-query
796 Control whether to stop the inferior if memory changes caused
797 by an instruction cannot be recorded.
802 The disassemble command now supports "start,+length" form of two arguments.
806 ** GDB now provides a new directory location, called the python directory,
807 where Python scripts written for GDB can be installed. The location
808 of that directory is <data-directory>/python, where <data-directory>
809 is the GDB data directory. For more details, see section `Scripting
810 GDB using Python' in the manual.
812 ** The GDB Python API now has access to breakpoints, symbols, symbol
813 tables, program spaces, inferiors, threads and frame's code blocks.
814 Additionally, GDB Parameters can now be created from the API, and
815 manipulated via set/show in the CLI.
817 ** New functions gdb.target_charset, gdb.target_wide_charset,
818 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
820 ** New exception gdb.GdbError.
822 ** Pretty-printers are now also looked up in the current program space.
824 ** Pretty-printers can now be individually enabled and disabled.
826 ** GDB now looks for names of Python scripts to auto-load in a
827 special section named `.debug_gdb_scripts', in addition to looking
828 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
830 * Tracepoint actions were unified with breakpoint commands. In particular,
831 there are no longer differences in "info break" output for breakpoints and
832 tracepoints and the "commands" command can be used for both tracepoints and
837 ARM Symbian arm*-*-symbianelf*
839 * D language support.
840 GDB now supports debugging programs written in the D programming
843 * GDB now supports the extended ptrace interface for PowerPC which is
844 available since Linux kernel version 2.6.34. This automatically enables
845 any hardware breakpoints and additional hardware watchpoints available in
846 the processor. The old ptrace interface exposes just one hardware
847 watchpoint and no hardware breakpoints.
849 * GDB is now able to use the Data Value Compare (DVC) register available on
850 embedded PowerPC processors to implement in hardware simple watchpoint
851 conditions of the form:
853 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
855 This works in native GDB running on Linux kernels with the extended ptrace
856 interface mentioned above.
858 *** Changes in GDB 7.1
864 GDB now supports importing of namespaces in C++. This enables the
865 user to inspect variables from imported namespaces. Support for
866 namepace aliasing has also been added. So, if a namespace is
867 aliased in the current scope (e.g. namepace C=A; ) the user can
868 print variables using the alias (e.g. (gdb) print C::x).
872 All known bugs relating to the printing of virtual base class were
873 fixed. It is now possible to call overloaded static methods using a
878 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
879 and reinterpret_cast<> are now handled by the C++ expression parser.
883 Xilinx MicroBlaze microblaze-*-*
888 Xilinx MicroBlaze microblaze
891 * Multi-program debugging.
893 GDB now has support for multi-program (a.k.a. multi-executable or
894 multi-exec) debugging. This allows for debugging multiple inferiors
895 simultaneously each running a different program under the same GDB
896 session. See "Debugging Multiple Inferiors and Programs" in the
897 manual for more information. This implied some user visible changes
898 in the multi-inferior support. For example, "info inferiors" now
899 lists inferiors that are not running yet or that have exited
900 already. See also "New commands" and "New options" below.
902 * New tracing features
904 GDB's tracepoint facility now includes several new features:
906 ** Trace state variables
908 GDB tracepoints now include support for trace state variables, which
909 are variables managed by the target agent during a tracing
910 experiment. They are useful for tracepoints that trigger each
911 other, so for instance one tracepoint can count hits in a variable,
912 and then a second tracepoint has a condition that is true when the
913 count reaches a particular value. Trace state variables share the
914 $-syntax of GDB convenience variables, and can appear in both
915 tracepoint actions and condition expressions. Use the "tvariable"
916 command to create, and "info tvariables" to view; see "Trace State
917 Variables" in the manual for more detail.
921 GDB now includes an option for defining fast tracepoints, which
922 targets may implement more efficiently, such as by installing a jump
923 into the target agent rather than a trap instruction. The resulting
924 speedup can be by two orders of magnitude or more, although the
925 tradeoff is that some program locations on some target architectures
926 might not allow fast tracepoint installation, for instance if the
927 instruction to be replaced is shorter than the jump. To request a
928 fast tracepoint, use the "ftrace" command, with syntax identical to
929 the regular trace command.
931 ** Disconnected tracing
933 It is now possible to detach GDB from the target while it is running
934 a trace experiment, then reconnect later to see how the experiment
935 is going. In addition, a new variable disconnected-tracing lets you
936 tell the target agent whether to continue running a trace if the
937 connection is lost unexpectedly.
941 GDB now has the ability to save the trace buffer into a file, and
942 then use that file as a target, similarly to you can do with
943 corefiles. You can select trace frames, print data that was
944 collected in them, and use tstatus to display the state of the
945 tracing run at the moment that it was saved. To create a trace
946 file, use "tsave <filename>", and to use it, do "target tfile
949 ** Circular trace buffer
951 You can ask the target agent to handle the trace buffer as a
952 circular buffer, discarding the oldest trace frames to make room for
953 newer ones, by setting circular-trace-buffer to on. This feature may
954 not be available for all target agents.
959 The disassemble command, when invoked with two arguments, now requires
960 the arguments to be comma-separated.
963 The info variables command now displays variable definitions. Files
964 which only declare a variable are not shown.
967 The source command is now capable of sourcing Python scripts.
968 This feature is dependent on the debugger being build with Python
971 Related to this enhancement is also the introduction of a new command
972 "set script-extension" (see below).
974 * New commands (for set/show, see "New options" below)
976 record save [<FILENAME>]
977 Save a file (in core file format) containing the process record
978 execution log for replay debugging at a later time.
980 record restore <FILENAME>
981 Restore the process record execution log that was saved at an
982 earlier time, for replay debugging.
984 add-inferior [-copies <N>] [-exec <FILENAME>]
987 clone-inferior [-copies <N>] [ID]
988 Make a new inferior ready to execute the same program another
994 maint info program-spaces
995 List the program spaces loaded into GDB.
997 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
998 show remote interrupt-sequence
999 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1000 as the sequence to the remote target in order to interrupt the execution.
1001 Ctrl-C is a default. Some system prefers BREAK which is high level of
1002 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1003 Magic SysRq g. It is BREAK signal and character 'g'.
1005 set remote interrupt-on-connect [on | off]
1006 show remote interrupt-on-connect
1007 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1008 remote target when gdb connects to it. This is needed when you debug
1011 set remotebreak [on | off]
1013 Deprecated. Use "set/show remote interrupt-sequence" instead.
1015 tvariable $NAME [ = EXP ]
1016 Create or modify a trace state variable.
1019 List trace state variables and their values.
1021 delete tvariable $NAME ...
1022 Delete one or more trace state variables.
1025 Evaluate the given expressions without collecting anything into the
1026 trace buffer. (Valid in tracepoint actions only.)
1028 ftrace FN / FILE:LINE / *ADDR
1029 Define a fast tracepoint at the given function, line, or address.
1031 * New expression syntax
1033 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1034 GDB now parses 0b101010 identically with 42.
1038 set follow-exec-mode new|same
1039 show follow-exec-mode
1040 Control whether GDB reuses the same inferior across an exec call or
1041 creates a new one. This is useful to be able to restart the old
1042 executable after the inferior having done an exec call.
1044 set default-collect EXPR, ...
1045 show default-collect
1046 Define a list of expressions to be collected at each tracepoint.
1047 This is a useful way to ensure essential items are not overlooked,
1048 such as registers or a critical global variable.
1050 set disconnected-tracing
1051 show disconnected-tracing
1052 If set to 1, the target is instructed to continue tracing if it
1053 loses its connection to GDB. If 0, the target is to stop tracing
1056 set circular-trace-buffer
1057 show circular-trace-buffer
1058 If set to on, the target is instructed to use a circular trace buffer
1059 and discard the oldest trace frames instead of stopping the trace due
1060 to a full trace buffer. If set to off, the trace stops when the buffer
1061 fills up. Some targets may not support this.
1063 set script-extension off|soft|strict
1064 show script-extension
1065 If set to "off", the debugger does not perform any script language
1066 recognition, and all sourced files are assumed to be GDB scripts.
1067 If set to "soft" (the default), files are sourced according to
1068 filename extension, falling back to GDB scripts if the first
1070 If set to "strict", files are sourced according to filename extension.
1072 set ada trust-PAD-over-XVS on|off
1073 show ada trust-PAD-over-XVS
1074 If off, activate a workaround against a bug in the debugging information
1075 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1076 the GCC sources for more information about the GNAT encoding and
1077 PAD types in particular). It is always safe to set this option to
1078 off, but this introduces a slight performance penalty. The default
1081 * Python API Improvements
1083 ** GDB provides the new class gdb.LazyString. This is useful in
1084 some pretty-printing cases. The new method gdb.Value.lazy_string
1085 provides a simple way to create objects of this type.
1087 ** The fields returned by gdb.Type.fields now have an
1088 `is_base_class' attribute.
1090 ** The new method gdb.Type.range returns the range of an array type.
1092 ** The new method gdb.parse_and_eval can be used to parse and
1093 evaluate an expression.
1095 * New remote packets
1098 Define a trace state variable.
1101 Get the current value of a trace state variable.
1104 Set desired tracing behavior upon disconnection.
1107 Set the trace buffer to be linear or circular.
1110 Get data about the tracepoints currently in use.
1114 Process record now works correctly with hardware watchpoints.
1116 Multiple bug fixes have been made to the mips-irix port, making it
1117 much more reliable. In particular:
1118 - Debugging threaded applications is now possible again. Previously,
1119 GDB would hang while starting the program, or while waiting for
1120 the program to stop at a breakpoint.
1121 - Attaching to a running process no longer hangs.
1122 - An error occurring while loading a core file has been fixed.
1123 - Changing the value of the PC register now works again. This fixes
1124 problems observed when using the "jump" command, or when calling
1125 a function from GDB, or even when assigning a new value to $pc.
1126 - With the "finish" and "return" commands, the return value for functions
1127 returning a small array is now correctly printed.
1128 - It is now possible to break on shared library code which gets executed
1129 during a shared library init phase (code executed while executing
1130 their .init section). Previously, the breakpoint would have no effect.
1131 - GDB is now able to backtrace through the signal handler for
1132 non-threaded programs.
1134 PIE (Position Independent Executable) programs debugging is now supported.
1135 This includes debugging execution of PIC (Position Independent Code) shared
1136 libraries although for that, it should be possible to run such libraries as an
1139 *** Changes in GDB 7.0
1141 * GDB now has an interface for JIT compilation. Applications that
1142 dynamically generate code can create symbol files in memory and register
1143 them with GDB. For users, the feature should work transparently, and
1144 for JIT developers, the interface is documented in the GDB manual in the
1145 "JIT Compilation Interface" chapter.
1147 * Tracepoints may now be conditional. The syntax is as for
1148 breakpoints; either an "if" clause appended to the "trace" command,
1149 or the "condition" command is available. GDB sends the condition to
1150 the target for evaluation using the same bytecode format as is used
1151 for tracepoint actions.
1153 * The disassemble command now supports: an optional /r modifier, print the
1154 raw instructions in hex as well as in symbolic form, and an optional /m
1155 modifier to print mixed source+assembly.
1157 * Process record and replay
1159 In a architecture environment that supports ``process record and
1160 replay'', ``process record and replay'' target can record a log of
1161 the process execution, and replay it with both forward and reverse
1164 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1165 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1166 set execution-direction {forward|reverse}, for targets that support
1169 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1170 feature is available with a native GDB running on kernel version
1173 * GDB now has support for multi-byte and wide character sets on the
1174 target. Strings whose character type is wchar_t, char16_t, or
1175 char32_t are now correctly printed. GDB supports wide- and unicode-
1176 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1177 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1178 `printf'. This feature requires iconv to work properly; if your
1179 system does not have a working iconv, GDB can use GNU libiconv. See
1180 the installation instructions for more information.
1182 * GDB now supports automatic retrieval of shared library files from
1183 remote targets. To use this feature, specify a system root that begins
1184 with the `remote:' prefix, either via the `set sysroot' command or via
1185 the `--with-sysroot' configure-time option.
1187 * "info sharedlibrary" now takes an optional regex of libraries to show,
1188 and it now reports if a shared library has no debugging information.
1190 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1191 now complete on file names.
1193 * When completing in expressions, gdb will attempt to limit
1194 completions to allowable structure or union fields, where appropriate.
1195 For instance, consider:
1197 # struct example { int f1; double f2; };
1198 # struct example variable;
1201 If the user types TAB at the end of this command line, the available
1202 completions will be "f1" and "f2".
1204 * Inlined functions are now supported. They show up in backtraces, and
1205 the "step", "next", and "finish" commands handle them automatically.
1207 * GDB now supports the token-splicing (##) and stringification (#)
1208 operators when expanding macros. It also supports variable-arity
1211 * GDB now supports inspecting extra signal information, exported by
1212 the new $_siginfo convenience variable. The feature is currently
1213 implemented on linux ARM, i386 and amd64.
1215 * GDB can now display the VFP floating point registers and NEON vector
1216 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1217 can provide these registers (requires Linux 2.6.30 or later). Remote
1218 and simulator targets may also provide them.
1220 * New remote packets
1223 Search memory for a sequence of bytes.
1226 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1227 operation over reliable transport links. Use of this packet is
1228 controlled by the `set remote noack-packet' command.
1231 Kill the process with the specified process ID. Use this in preference
1232 to `k' when multiprocess protocol extensions are supported.
1235 Obtains additional operating system information
1239 Read or write additional signal information.
1241 * Removed remote protocol undocumented extension
1243 An undocumented extension to the remote protocol's `S' stop reply
1244 packet that permited the stub to pass a process id was removed.
1245 Remote servers should use the `T' stop reply packet instead.
1247 * GDB now supports multiple function calling conventions according to the
1248 DWARF-2 DW_AT_calling_convention function attribute.
1250 * The SH target utilizes the aforementioned change to distinguish between gcc
1251 and Renesas calling convention. It also adds the new CLI commands
1252 `set/show sh calling-convention'.
1254 * GDB can now read compressed debug sections, as produced by GNU gold
1255 with the --compress-debug-sections=zlib flag.
1257 * 64-bit core files are now supported on AIX.
1259 * Thread switching is now supported on Tru64.
1261 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1262 which will be allocated using malloc later in program execution.
1264 * The qXfer:libraries:read remote procotol packet now allows passing a
1265 list of section offsets.
1267 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1268 conditions handling signals delivered during attach or thread creation
1269 have also been fixed.
1271 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1272 From the user's standpoint, all unqualified instances of True and False
1273 are treated as the standard definitions, regardless of context.
1275 * GDB now parses C++ symbol and type names more flexibly. For
1278 template<typename T> class C { };
1281 GDB will now correctly handle all of:
1283 ptype C<char const *>
1284 ptype C<char const*>
1285 ptype C<const char *>
1286 ptype C<const char*>
1288 * New features in the GDB remote stub, gdbserver
1290 - The "--wrapper" command-line argument tells gdbserver to use a
1291 wrapper program to launch programs for debugging.
1293 - On PowerPC and S/390 targets, it is now possible to use a single
1294 gdbserver executable to debug both 32-bit and 64-bit programs.
1295 (This requires gdbserver itself to be built as a 64-bit executable.)
1297 - gdbserver uses the new noack protocol mode for TCP connections to
1298 reduce communications latency, if also supported and enabled in GDB.
1300 - Support for the sparc64-linux-gnu target is now included in
1303 - The amd64-linux build of gdbserver now supports debugging both
1304 32-bit and 64-bit programs.
1306 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1307 now support hardware watchpoints, and will use them automatically
1312 GDB now has support for scripting using Python. Whether this is
1313 available is determined at configure time.
1315 New GDB commands can now be written in Python.
1317 * Ada tasking support
1319 Ada tasks can now be inspected in GDB. The following commands have
1323 Print the list of Ada tasks.
1325 Print detailed information about task number N.
1327 Print the task number of the current task.
1329 Switch the context of debugging to task number N.
1331 * Support for user-defined prefixed commands. The "define" command can
1332 add new commands to existing prefixes, e.g. "target".
1334 * Multi-inferior, multi-process debugging.
1336 GDB now has generalized support for multi-inferior debugging. See
1337 "Debugging Multiple Inferiors" in the manual for more information.
1338 Although availability still depends on target support, the command
1339 set is more uniform now. The GNU/Linux specific multi-forks support
1340 has been migrated to this new framework. This implied some user
1341 visible changes; see "New commands" and also "Removed commands"
1344 * Target descriptions can now describe the target OS ABI. See the
1345 "Target Description Format" section in the user manual for more
1348 * Target descriptions can now describe "compatible" architectures
1349 to indicate that the target can execute applications for a different
1350 architecture in addition to those for the main target architecture.
1351 See the "Target Description Format" section in the user manual for
1354 * Multi-architecture debugging.
1356 GDB now includes general supports for debugging applications on
1357 hybrid systems that use more than one single processor architecture
1358 at the same time. Each such hybrid architecture still requires
1359 specific support to be added. The only hybrid architecture supported
1360 in this version of GDB is the Cell Broadband Engine.
1362 * GDB now supports integrated debugging of Cell/B.E. applications that
1363 use both the PPU and SPU architectures. To enable support for hybrid
1364 Cell/B.E. debugging, you need to configure GDB to support both the
1365 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1366 --enable-targets configure option.
1368 * Non-stop mode debugging.
1370 For some targets, GDB now supports an optional mode of operation in
1371 which you can examine stopped threads while other threads continue
1372 to execute freely. This is referred to as non-stop mode, with the
1373 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1374 section in the user manual for more information.
1376 To be able to support remote non-stop debugging, a remote stub needs
1377 to implement the non-stop mode remote protocol extensions, as
1378 described in the "Remote Non-Stop" section of the user manual. The
1379 GDB remote stub, gdbserver, has been adjusted to support these
1380 extensions on linux targets.
1382 * New commands (for set/show, see "New options" below)
1384 catch syscall [NAME(S) | NUMBER(S)]
1385 Catch system calls. Arguments, which should be names of system
1386 calls or their numbers, mean catch only those syscalls. Without
1387 arguments, every syscall will be caught. When the inferior issues
1388 any of the specified syscalls, GDB will stop and announce the system
1389 call, both when it is called and when its call returns. This
1390 feature is currently available with a native GDB running on the
1391 Linux Kernel, under the following architectures: x86, x86_64,
1392 PowerPC and PowerPC64.
1394 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1396 Search memory for a sequence of bytes.
1398 maint set python print-stack
1399 maint show python print-stack
1400 Show a stack trace when an error is encountered in a Python script.
1403 Invoke CODE by passing it to the Python interpreter.
1408 These allow macros to be defined, undefined, and listed
1412 Show operating system information about processes.
1415 List the inferiors currently under GDB's control.
1418 Switch focus to inferior number NUM.
1421 Detach from inferior number NUM.
1424 Kill inferior number NUM.
1428 set spu stop-on-load
1429 show spu stop-on-load
1430 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1432 set spu auto-flush-cache
1433 show spu auto-flush-cache
1434 Control whether to automatically flush the software-managed cache
1435 during Cell/B.E. debugging.
1437 set sh calling-convention
1438 show sh calling-convention
1439 Control the calling convention used when calling SH target functions.
1442 show debug timestamp
1443 Control display of timestamps with GDB debugging output.
1445 set disassemble-next-line
1446 show disassemble-next-line
1447 Control display of disassembled source lines or instructions when
1450 set remote noack-packet
1451 show remote noack-packet
1452 Set/show the use of remote protocol QStartNoAckMode packet. See above
1453 under "New remote packets."
1455 set remote query-attached-packet
1456 show remote query-attached-packet
1457 Control use of remote protocol `qAttached' (query-attached) packet.
1459 set remote read-siginfo-object
1460 show remote read-siginfo-object
1461 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1464 set remote write-siginfo-object
1465 show remote write-siginfo-object
1466 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1469 set remote reverse-continue
1470 show remote reverse-continue
1471 Control use of remote protocol 'bc' (reverse-continue) packet.
1473 set remote reverse-step
1474 show remote reverse-step
1475 Control use of remote protocol 'bs' (reverse-step) packet.
1477 set displaced-stepping
1478 show displaced-stepping
1479 Control displaced stepping mode. Displaced stepping is a way to
1480 single-step over breakpoints without removing them from the debuggee.
1481 Also known as "out-of-line single-stepping".
1484 show debug displaced
1485 Control display of debugging info for displaced stepping.
1487 maint set internal-error
1488 maint show internal-error
1489 Control what GDB does when an internal error is detected.
1491 maint set internal-warning
1492 maint show internal-warning
1493 Control what GDB does when an internal warning is detected.
1498 Use a wrapper program to launch programs for debugging.
1500 set multiple-symbols (all|ask|cancel)
1501 show multiple-symbols
1502 The value of this variable can be changed to adjust the debugger behavior
1503 when an expression or a breakpoint location contains an ambiguous symbol
1504 name (an overloaded function name, for instance).
1506 set breakpoint always-inserted
1507 show breakpoint always-inserted
1508 Keep breakpoints always inserted in the target, as opposed to inserting
1509 them when resuming the target, and removing them when the target stops.
1510 This option can improve debugger performance on slow remote targets.
1512 set arm fallback-mode (arm|thumb|auto)
1513 show arm fallback-mode
1514 set arm force-mode (arm|thumb|auto)
1516 These commands control how ARM GDB determines whether instructions
1517 are ARM or Thumb. The default for both settings is auto, which uses
1518 the current CPSR value for instructions without symbols; previous
1519 versions of GDB behaved as if "set arm fallback-mode arm".
1521 set disable-randomization
1522 show disable-randomization
1523 Standalone programs run with the virtual address space randomization enabled
1524 by default on some platforms. This option keeps the addresses stable across
1525 multiple debugging sessions.
1529 Control whether other threads are stopped or not when some thread hits
1534 Requests that asynchronous execution is enabled in the target, if available.
1535 In this case, it's possible to resume target in the background, and interact
1536 with GDB while the target is running. "show target-async" displays the
1537 current state of asynchronous execution of the target.
1539 set target-wide-charset
1540 show target-wide-charset
1541 The target-wide-charset is the name of the character set that GDB
1542 uses when printing characters whose type is wchar_t.
1544 set tcp auto-retry (on|off)
1546 set tcp connect-timeout
1547 show tcp connect-timeout
1548 These commands allow GDB to retry failed TCP connections to a remote stub
1549 with a specified timeout period; this is useful if the stub is launched
1550 in parallel with GDB but may not be ready to accept connections immediately.
1552 set libthread-db-search-path
1553 show libthread-db-search-path
1554 Control list of directories which GDB will search for appropriate
1557 set schedule-multiple (on|off)
1558 show schedule-multiple
1559 Allow GDB to resume all threads of all processes or only threads of
1560 the current process.
1564 Use more aggressive caching for accesses to the stack. This improves
1565 performance of remote debugging (particularly backtraces) without
1566 affecting correctness.
1568 set interactive-mode (on|off|auto)
1569 show interactive-mode
1570 Control whether GDB runs in interactive mode (on) or not (off).
1571 When in interactive mode, GDB waits for the user to answer all
1572 queries. Otherwise, GDB does not wait and assumes the default
1573 answer. When set to auto (the default), GDB determines which
1574 mode to use based on the stdin settings.
1579 For program forks, this is replaced by the new more generic `info
1580 inferiors' command. To list checkpoints, you can still use the
1581 `info checkpoints' command, which was an alias for the `info forks'
1585 Replaced by the new `inferior' command. To switch between
1586 checkpoints, you can still use the `restart' command, which was an
1587 alias for the `fork' command.
1590 This is removed, since some targets don't have a notion of
1591 processes. To switch between processes, you can still use the
1592 `inferior' command using GDB's own inferior number.
1595 For program forks, this is replaced by the new more generic `kill
1596 inferior' command. To delete a checkpoint, you can still use the
1597 `delete checkpoint' command, which was an alias for the `delete
1601 For program forks, this is replaced by the new more generic `detach
1602 inferior' command. To detach a checkpoint, you can still use the
1603 `detach checkpoint' command, which was an alias for the `detach
1606 * New native configurations
1608 x86/x86_64 Darwin i[34567]86-*-darwin*
1610 x86_64 MinGW x86_64-*-mingw*
1614 Lattice Mico32 lm32-*
1615 x86 DICOS i[34567]86-*-dicos*
1616 x86_64 DICOS x86_64-*-dicos*
1619 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1620 (mingw32ce) debugging.
1626 These commands were actually not implemented on any target.
1628 *** Changes in GDB 6.8
1630 * New native configurations
1632 NetBSD/hppa hppa*-*netbsd*
1633 Xtensa GNU/Linux xtensa*-*-linux*
1637 NetBSD/hppa hppa*-*-netbsd*
1638 Xtensa GNU/Lunux xtensa*-*-linux*
1640 * Change in command line behavior -- corefiles vs. process ids.
1642 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1643 attaching to process NUMBER fails, GDB no longer attempts to open a
1644 core file named NUMBER. Attaching to a program using the -c option
1645 is no longer supported. Instead, use the '-p' or '--pid' options.
1647 * GDB can now be built as a native debugger for debugging Windows x86
1648 (mingw32) Portable Executable (PE) programs.
1650 * Pending breakpoints no longer change their number when their address
1653 * GDB now supports breakpoints with multiple locations,
1654 including breakpoints on C++ constructors, inside C++ templates,
1655 and in inlined functions.
1657 * GDB's ability to debug optimized code has been improved. GDB more
1658 accurately identifies function bodies and lexical blocks that occupy
1659 more than one contiguous range of addresses.
1661 * Target descriptions can now describe registers for PowerPC.
1663 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1664 registers on PowerPC targets.
1666 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1667 targets even when the libthread_db library is not available.
1669 * The GDB remote stub, gdbserver, now supports the new file transfer
1670 commands (remote put, remote get, and remote delete).
1672 * The GDB remote stub, gdbserver, now supports run and attach in
1673 extended-remote mode.
1675 * hppa*64*-*-hpux11* target broken
1676 The debugger is unable to start a program and fails with the following
1677 error: "Error trying to get information about dynamic linker".
1678 The gdb-6.7 release is also affected.
1680 * GDB now supports the --enable-targets= configure option to allow
1681 building a single GDB executable that supports multiple remote
1682 target architectures.
1684 * GDB now supports debugging C and C++ programs which use the
1685 Decimal Floating Point extension. In addition, the PowerPC target
1686 now has a set of pseudo-registers to inspect decimal float values
1687 stored in two consecutive float registers.
1689 * The -break-insert MI command can optionally create pending
1692 * Improved support for debugging Ada
1693 Many improvements to the Ada language support have been made. These
1695 - Better support for Ada2005 interface types
1696 - Improved handling of arrays and slices in general
1697 - Better support for Taft-amendment types
1698 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1700 - Improved command completion in Ada
1703 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1708 set print frame-arguments (all|scalars|none)
1709 show print frame-arguments
1710 The value of this variable can be changed to control which argument
1711 values should be printed by the debugger when displaying a frame.
1716 Transfer files to and from a remote target, and delete remote files.
1723 Transfer files to and from a remote target, and delete remote files.
1725 * New remote packets
1732 Open, close, read, write, and delete files on the remote system.
1735 Attach to an existing process on the remote system, in extended-remote
1739 Run a new process on the remote system, in extended-remote mode.
1741 *** Changes in GDB 6.7
1743 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1744 bfd, libiberty and opcodes, as revealed by static analysis donated by
1745 Coverity, Inc. (http://scan.coverity.com).
1747 * When looking up multiply-defined global symbols, GDB will now prefer the
1748 symbol definition in the current shared library if it was built using the
1749 -Bsymbolic linker option.
1751 * When the Text User Interface (TUI) is not configured, GDB will now
1752 recognize the -tui command-line option and print a message that the TUI
1755 * The GDB remote stub, gdbserver, now has lower overhead for high
1756 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1758 * GDB for MIPS targets now autodetects whether a remote target provides
1759 32-bit or 64-bit register values.
1761 * Support for C++ member pointers has been improved.
1763 * GDB now understands XML target descriptions, which specify the
1764 target's overall architecture. GDB can read a description from
1765 a local file or over the remote serial protocol.
1767 * Vectors of single-byte data use a new integer type which is not
1768 automatically displayed as character or string data.
1770 * The /s format now works with the print command. It displays
1771 arrays of single-byte integers and pointers to single-byte integers
1774 * Target descriptions can now describe target-specific registers,
1775 for architectures which have implemented the support (currently
1776 only ARM, M68K, and MIPS).
1778 * GDB and the GDB remote stub, gdbserver, now support the XScale
1781 * The GDB remote stub, gdbserver, has been updated to support
1782 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1783 has been rewritten to use the standard GDB remote protocol.
1785 * GDB can now step into C++ functions which are called through thunks.
1787 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1789 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1790 layout. It also supports a TextSeg= and DataSeg= response when only
1791 segment base addresses (rather than offsets) are available.
1793 * The /i format now outputs any trailing branch delay slot instructions
1794 immediately following the last instruction within the count specified.
1796 * The GDB remote protocol "T" stop reply packet now supports a
1797 "library" response. Combined with the new "qXfer:libraries:read"
1798 packet, this response allows GDB to debug shared libraries on targets
1799 where the operating system manages the list of loaded libraries (e.g.
1800 Windows and SymbianOS).
1802 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1803 (DLLs) on Windows and Windows CE targets.
1805 * GDB now supports a faster verification that a .debug file matches its binary
1806 according to its build-id signature, if the signature is present.
1812 Enable or disable hardware flow control (RTS/CTS) on the serial port
1813 when debugging using remote targets.
1815 set mem inaccessible-by-default
1816 show mem inaccessible-by-default
1817 If the target supplies a memory map, for instance via the remote
1818 protocol's "qXfer:memory-map:read" packet, setting this variable
1819 prevents GDB from accessing memory outside the memory map. This
1820 is useful for targets with memory mapped registers or which react
1821 badly to accesses of unmapped address space.
1823 set breakpoint auto-hw
1824 show breakpoint auto-hw
1825 If the target supplies a memory map, for instance via the remote
1826 protocol's "qXfer:memory-map:read" packet, setting this variable
1827 lets GDB use hardware breakpoints automatically for memory regions
1828 where it can not use software breakpoints. This covers both the
1829 "break" command and internal breakpoints used for other commands
1830 including "next" and "finish".
1833 catch exception unhandled
1834 Stop the program execution when Ada exceptions are raised.
1837 Stop the program execution when an Ada assertion failed.
1841 Set an alternate system root for target files. This is a more
1842 general version of "set solib-absolute-prefix", which is now
1843 an alias to "set sysroot".
1846 Provide extended SPU facility status information. This set of
1847 commands is available only when debugging the Cell/B.E. SPU
1850 * New native configurations
1852 OpenBSD/sh sh*-*openbsd*
1855 unset tdesc filename
1857 Use the specified local file as an XML target description, and do
1858 not query the target for its built-in description.
1862 OpenBSD/sh sh*-*-openbsd*
1863 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1864 Toshiba Media Processor mep-elf
1866 * New remote packets
1869 Ignore the specified signals; pass them directly to the debugged program
1870 without stopping other threads or reporting them to GDB.
1872 qXfer:features:read:
1873 Read an XML target description from the target, which describes its
1878 Read or write contents of an spufs file on the target system. These
1879 packets are available only on the Cell/B.E. SPU architecture.
1881 qXfer:libraries:read:
1882 Report the loaded shared libraries. Combined with new "T" packet
1883 response, this packet allows GDB to debug shared libraries on
1884 targets where the operating system manages the list of loaded
1885 libraries (e.g. Windows and SymbianOS).
1889 Support for these obsolete configurations has been removed.
1897 i[34567]86-*-lynxos*
1898 i[34567]86-*-netware*
1899 i[34567]86-*-sco3.2v5*
1900 i[34567]86-*-sco3.2v4*
1902 i[34567]86-*-sysv4.2*
1905 i[34567]86-*-unixware2*
1906 i[34567]86-*-unixware*
1915 * Other removed features
1922 Various m68k-only ROM monitors.
1929 Various Renesas ROM monitors and debugging interfaces for SH and
1934 Support for a Macraigor serial interface to on-chip debugging.
1935 GDB does not directly support the newer parallel or USB
1940 A debug information format. The predecessor to DWARF 2 and
1941 DWARF 3, which are still supported.
1943 Support for the HP aCC compiler on HP-UX/PA-RISC
1945 SOM-encapsulated symbolic debugging information, automatic
1946 invocation of pxdb, and the aCC custom C++ ABI. This does not
1947 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1948 with aCC can still be debugged on an assembly level.
1950 MIPS ".pdr" sections
1952 A MIPS-specific format used to describe stack frame layout
1953 in debugging information.
1957 GDB could work with an older version of Guile to debug
1958 the interpreter and Scheme programs running in it.
1960 set mips stack-arg-size
1961 set mips saved-gpreg-size
1963 Use "set mips abi" to control parameter passing for MIPS.
1965 *** Changes in GDB 6.6
1970 Cell Broadband Engine SPU spu-elf
1972 * GDB can now be configured as a cross-debugger targeting native Windows
1973 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1974 running on a Windows system over TCP/IP to debug Windows programs.
1976 * The GDB remote stub, gdbserver, has been updated to support Windows and
1977 Cygwin debugging. Both single-threaded and multi-threaded programs are
1980 * The "set trust-readonly-sections" command works again. This command was
1981 broken in GDB 6.3, 6.4, and 6.5.
1983 * The "load" command now supports writing to flash memory, if the remote
1984 stub provides the required support.
1986 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1987 longer requires symbolic debug information (e.g. DWARF-2).
1992 unset substitute-path
1993 show substitute-path
1994 Manage a list of substitution rules that GDB uses to rewrite the name
1995 of the directories where the sources are located. This can be useful
1996 for instance when the sources were moved to a different location
1997 between compilation and debugging.
2001 Print each CLI command as it is executed. Each command is prefixed with
2002 a number of `+' symbols representing the nesting depth.
2003 The source command now has a `-v' option to enable the same feature.
2007 The ARM Demon monitor support (RDP protocol, "target rdp").
2009 Kernel Object Display, an embedded debugging feature which only worked with
2010 an obsolete version of Cisco IOS.
2012 The 'set download-write-size' and 'show download-write-size' commands.
2014 * New remote packets
2017 Tell a stub about GDB client features, and request remote target features.
2018 The first feature implemented is PacketSize, which allows the target to
2019 specify the size of packets it can handle - to minimize the number of
2020 packets required and improve performance when connected to a remote
2024 Fetch an OS auxilliary vector from the remote stub. This packet is a
2025 more efficient replacement for qPart:auxv:read.
2027 qXfer:memory-map:read:
2028 Fetch a memory map from the remote stub, including information about
2029 RAM, ROM, and flash memory devices.
2034 Erase and program a flash memory device.
2036 * Removed remote packets
2039 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2040 used it, and only gdbserver implemented it.
2042 *** Changes in GDB 6.5
2046 Renesas M32C/M16C m32c-elf
2048 Morpho Technologies ms1 ms1-elf
2052 init-if-undefined Initialize a convenience variable, but
2053 only if it doesn't already have a value.
2055 The following commands are presently only implemented for native GNU/Linux:
2057 checkpoint Save a snapshot of the program state.
2059 restart <n> Return the program state to a
2060 previously saved state.
2062 info checkpoints List currently saved checkpoints.
2064 delete-checkpoint <n> Delete a previously saved checkpoint.
2066 set|show detach-on-fork Tell gdb whether to detach from a newly
2067 forked process, or to keep debugging it.
2069 info forks List forks of the user program that
2070 are available to be debugged.
2072 fork <n> Switch to debugging one of several
2073 forks of the user program that are
2074 available to be debugged.
2076 delete-fork <n> Delete a fork from the list of forks
2077 that are available to be debugged (and
2078 kill the forked process).
2080 detach-fork <n> Delete a fork from the list of forks
2081 that are available to be debugged (and
2082 allow the process to continue).
2086 Morpho Technologies ms2 ms1-elf
2088 * Improved Windows host support
2090 GDB now builds as a cross debugger hosted on i686-mingw32, including
2091 native console support, and remote communications using either
2092 network sockets or serial ports.
2094 * Improved Modula-2 language support
2096 GDB can now print most types in the Modula-2 syntax. This includes:
2097 basic types, set types, record types, enumerated types, range types,
2098 pointer types and ARRAY types. Procedure var parameters are correctly
2099 printed and hexadecimal addresses and character constants are also
2100 written in the Modula-2 syntax. Best results can be obtained by using
2101 GNU Modula-2 together with the -gdwarf-2 command line option.
2105 The ARM rdi-share module.
2107 The Netware NLM debug server.
2109 *** Changes in GDB 6.4
2111 * New native configurations
2113 OpenBSD/arm arm*-*-openbsd*
2114 OpenBSD/mips64 mips64-*-openbsd*
2118 Morpho Technologies ms1 ms1-elf
2120 * New command line options
2122 --batch-silent As for --batch, but totally silent.
2123 --return-child-result The debugger will exist with the same value
2124 the child (debugged) program exited with.
2125 --eval-command COMMAND, -ex COMMAND
2126 Execute a single GDB CLI command. This may be
2127 specified multiple times and in conjunction
2128 with the --command (-x) option.
2130 * Deprecated commands removed
2132 The following commands, that were deprecated in 2000, have been
2136 set|show arm disassembly-flavor set|show arm disassembler
2137 othernames set arm disassembler
2138 set|show remotedebug set|show debug remote
2139 set|show archdebug set|show debug arch
2140 set|show eventdebug set|show debug event
2143 * New BSD user-level threads support
2145 It is now possible to debug programs using the user-level threads
2146 library on OpenBSD and FreeBSD. Currently supported (target)
2149 FreeBSD/amd64 x86_64-*-freebsd*
2150 FreeBSD/i386 i386-*-freebsd*
2151 OpenBSD/i386 i386-*-openbsd*
2153 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2154 are not yet supported.
2156 * New support for Matsushita MN10300 w/sim added
2157 (Work in progress). mn10300-elf.
2159 * REMOVED configurations and files
2161 VxWorks and the XDR protocol *-*-vxworks
2162 Motorola MCORE mcore-*-*
2163 National Semiconductor NS32000 ns32k-*-*
2165 * New "set print array-indexes" command
2167 After turning this setting "on", GDB prints the index of each element
2168 when displaying arrays. The default is "off" to preserve the previous
2171 * VAX floating point support
2173 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2175 * User-defined command support
2177 In addition to using $arg0..$arg9 for argument passing, it is now possible
2178 to use $argc to determine now many arguments have been passed. See the
2179 section on user-defined commands in the user manual for more information.
2181 *** Changes in GDB 6.3:
2183 * New command line option
2185 GDB now accepts -l followed by a number to set the timeout for remote
2188 * GDB works with GCC -feliminate-dwarf2-dups
2190 GDB now supports a more compact representation of DWARF-2 debug
2191 information using DW_FORM_ref_addr references. These are produced
2192 by GCC with the option -feliminate-dwarf2-dups and also by some
2193 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2194 to use -feliminate-dwarf2-dups.
2196 * Internationalization
2198 When supported by the host system, GDB will be built with
2199 internationalization (libintl). The task of marking up the sources is
2200 continued, we're looking forward to our first translation.
2204 Initial support for debugging programs compiled with the GNAT
2205 implementation of the Ada programming language has been integrated
2206 into GDB. In this release, support is limited to expression evaluation.
2208 * New native configurations
2210 GNU/Linux/m32r m32r-*-linux-gnu
2214 GDB's remote protocol now includes support for the 'p' packet. This
2215 packet is used to fetch individual registers from a remote inferior.
2217 * END-OF-LIFE registers[] compatibility module
2219 GDB's internal register infrastructure has been completely rewritten.
2220 The new infrastructure making possible the implementation of key new
2221 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2224 GDB 6.3 will be the last release to include the the registers[]
2225 compatibility module that allowed out-of-date configurations to
2226 continue to work. This change directly impacts the following
2236 powerpc bdm protocol
2238 Unless there is activity to revive these configurations, they will be
2239 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2241 * OBSOLETE configurations and files
2243 Configurations that have been declared obsolete in this release have
2244 been commented out. Unless there is activity to revive these
2245 configurations, the next release of GDB will have their sources
2246 permanently REMOVED.
2255 *** Changes in GDB 6.2.1:
2257 * MIPS `break main; run' gave an heuristic-fence-post warning
2259 When attempting to run even a simple program, a warning about
2260 heuristic-fence-post being hit would be reported. This problem has
2263 * MIPS IRIX 'long double' crashed GDB
2265 When examining a long double variable, GDB would get a segmentation
2266 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2267 IRIX long double values).
2271 A bug in the VAX stack code was causing problems with the "next"
2272 command. This problem has been fixed.
2274 *** Changes in GDB 6.2:
2276 * Fix for ``many threads''
2278 On GNU/Linux systems that use the NPTL threads library, a program
2279 rapidly creating and deleting threads would confuse GDB leading to the
2282 ptrace: No such process.
2283 thread_db_get_info: cannot get thread info: generic error
2285 This problem has been fixed.
2287 * "-async" and "-noasync" options removed.
2289 Support for the broken "-noasync" option has been removed (it caused
2292 * New ``start'' command.
2294 This command runs the program until the begining of the main procedure.
2296 * New BSD Kernel Data Access Library (libkvm) interface
2298 Using ``target kvm'' it is now possible to debug kernel core dumps and
2299 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2300 platforms. Currently supported (native-only) configurations are:
2302 FreeBSD/amd64 x86_64-*-freebsd*
2303 FreeBSD/i386 i?86-*-freebsd*
2304 NetBSD/i386 i?86-*-netbsd*
2305 NetBSD/m68k m68*-*-netbsd*
2306 NetBSD/sparc sparc-*-netbsd*
2307 OpenBSD/amd64 x86_64-*-openbsd*
2308 OpenBSD/i386 i?86-*-openbsd*
2309 OpenBSD/m68k m68*-openbsd*
2310 OpenBSD/sparc sparc-*-openbsd*
2312 * Signal trampoline code overhauled
2314 Many generic problems with GDB's signal handling code have been fixed.
2315 These include: backtraces through non-contiguous stacks; recognition
2316 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2317 call; backtrace through a signal trampoline; step into and out of
2318 signal handlers; and single-stepping in the signal trampoline.
2320 Please note that kernel bugs are a limiting factor here. These
2321 features have been shown to work on an s390 GNU/Linux system that
2322 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2324 * Cygwin support for DWARF 2 added.
2326 * New native configurations
2328 GNU/Linux/hppa hppa*-*-linux*
2329 OpenBSD/hppa hppa*-*-openbsd*
2330 OpenBSD/m68k m68*-*-openbsd*
2331 OpenBSD/m88k m88*-*-openbsd*
2332 OpenBSD/powerpc powerpc-*-openbsd*
2333 NetBSD/vax vax-*-netbsd*
2334 OpenBSD/vax vax-*-openbsd*
2336 * END-OF-LIFE frame compatibility module
2338 GDB's internal frame infrastructure has been completely rewritten.
2339 The new infrastructure making it possible to support key new features
2340 including DWARF 2 Call Frame Information. To aid in the task of
2341 migrating old configurations to this new infrastructure, a
2342 compatibility module, that allowed old configurations to continue to
2343 work, was also included.
2345 GDB 6.2 will be the last release to include this frame compatibility
2346 module. This change directly impacts the following configurations:
2356 Unless there is activity to revive these configurations, they will be
2357 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2359 * REMOVED configurations and files
2361 Sun 3, running SunOS 3 m68*-*-sunos3*
2362 Sun 3, running SunOS 4 m68*-*-sunos4*
2363 Sun 2, running SunOS 3 m68000-*-sunos3*
2364 Sun 2, running SunOS 4 m68000-*-sunos4*
2365 Motorola 680x0 running LynxOS m68*-*-lynxos*
2366 AT&T 3b1/Unix pc m68*-att-*
2367 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2368 decstation mips-dec-* mips-little-*
2369 riscos mips-*-riscos* mips-*-sysv*
2370 sonymips mips-sony-*
2371 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2373 *** Changes in GDB 6.1.1:
2375 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2377 The TUI (Text-mode User Interface) is now built as part of a default
2378 GDB configuration. It is enabled by either selecting the TUI with the
2379 command line option "-i=tui" or by running the separate "gdbtui"
2380 program. For more information on the TUI, see the manual "Debugging
2383 * Pending breakpoint support (also included in GDB 6.1)
2385 Support has been added to allow you to specify breakpoints in shared
2386 libraries that have not yet been loaded. If a breakpoint location
2387 cannot be found, and the "breakpoint pending" option is set to auto,
2388 GDB queries you if you wish to make the breakpoint pending on a future
2389 shared-library load. If and when GDB resolves the breakpoint symbol,
2390 the pending breakpoint is removed as one or more regular breakpoints
2393 Pending breakpoints are very useful for GCJ Java debugging.
2395 * Fixed ISO-C build problems
2397 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2398 non ISO-C code that stopped them being built using a more strict ISO-C
2399 compiler (e.g., IBM's C compiler).
2401 * Fixed build problem on IRIX 5
2403 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2404 wasn't able to compile compile on an IRIX 5 system.
2406 * Added execute permission to gdb/gdbserver/configure
2408 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2409 permission. This bug would cause configure to fail on a number of
2410 systems (Solaris, IRIX). Ref: server/519.
2412 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2414 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2415 has been updated to use constant array sizes.
2417 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2419 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2420 its generated DWARF Call Frame Info. This encoding was causing GDB to
2421 panic, that panic has been fixed. Ref: gdb/1628.
2423 * Fixed a problem when examining parameters in shared library code.
2425 When examining parameters in optimized shared library code generated
2426 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2427 not available''. GDB now correctly displays the variable's value.
2429 *** Changes in GDB 6.1:
2431 * Removed --with-mmalloc
2433 Support for the mmalloc memory manager has been removed, as it
2434 conflicted with the internal gdb byte cache.
2436 * Changes in AMD64 configurations
2438 The AMD64 target now includes the %cs and %ss registers. As a result
2439 the AMD64 remote protocol has changed; this affects the floating-point
2440 and SSE registers. If you rely on those registers for your debugging,
2441 you should upgrade gdbserver on the remote side.
2443 * Revised SPARC target
2445 The SPARC target has been completely revised, incorporating the
2446 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2447 support for LynxOS and SunOS 4 has been dropped. Calling functions
2448 from within GDB on operating systems with a non-executable stack
2449 (Solaris, OpenBSD) now works.
2453 GDB has a new C++ demangler which does a better job on the mangled
2454 names generated by current versions of g++. It also runs faster, so
2455 with this and other changes gdb should now start faster on large C++
2458 * DWARF 2 Location Expressions
2460 GDB support for location expressions has been extended to support function
2461 arguments and frame bases. Older versions of GDB could crash when they
2464 * C++ nested types and namespaces
2466 GDB's support for nested types and namespaces in C++ has been
2467 improved, especially if you use the DWARF 2 debugging format. (This
2468 is the default for recent versions of GCC on most platforms.)
2469 Specifically, if you have a class "Inner" defined within a class or
2470 namespace "Outer", then GDB realizes that the class's name is
2471 "Outer::Inner", not simply "Inner". This should greatly reduce the
2472 frequency of complaints about not finding RTTI symbols. In addition,
2473 if you are stopped at inside of a function defined within a namespace,
2474 GDB modifies its name lookup accordingly.
2476 * New native configurations
2478 NetBSD/amd64 x86_64-*-netbsd*
2479 OpenBSD/amd64 x86_64-*-openbsd*
2480 OpenBSD/alpha alpha*-*-openbsd*
2481 OpenBSD/sparc sparc-*-openbsd*
2482 OpenBSD/sparc64 sparc64-*-openbsd*
2484 * New debugging protocols
2486 M32R with SDI protocol m32r-*-elf*
2488 * "set prompt-escape-char" command deleted.
2490 The command "set prompt-escape-char" has been deleted. This command,
2491 and its very obscure effet on GDB's prompt, was never documented,
2492 tested, nor mentioned in the NEWS file.
2494 * OBSOLETE configurations and files
2496 Configurations that have been declared obsolete in this release have
2497 been commented out. Unless there is activity to revive these
2498 configurations, the next release of GDB will have their sources
2499 permanently REMOVED.
2501 Sun 3, running SunOS 3 m68*-*-sunos3*
2502 Sun 3, running SunOS 4 m68*-*-sunos4*
2503 Sun 2, running SunOS 3 m68000-*-sunos3*
2504 Sun 2, running SunOS 4 m68000-*-sunos4*
2505 Motorola 680x0 running LynxOS m68*-*-lynxos*
2506 AT&T 3b1/Unix pc m68*-att-*
2507 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2508 decstation mips-dec-* mips-little-*
2509 riscos mips-*-riscos* mips-*-sysv*
2510 sonymips mips-sony-*
2511 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2513 * REMOVED configurations and files
2515 SGI Irix-4.x mips-sgi-irix4 or iris4
2516 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2517 Z8000 simulator z8k-zilog-none or z8ksim
2518 Matsushita MN10200 w/simulator mn10200-*-*
2519 H8/500 simulator h8500-hitachi-hms or h8500hms
2520 HP/PA running BSD hppa*-*-bsd*
2521 HP/PA running OSF/1 hppa*-*-osf*
2522 HP/PA Pro target hppa*-*-pro*
2523 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2524 386BSD i[3456]86-*-bsd*
2525 Sequent family i[3456]86-sequent-sysv4*
2526 i[3456]86-sequent-sysv*
2527 i[3456]86-sequent-bsd*
2528 SPARC running LynxOS sparc-*-lynxos*
2529 SPARC running SunOS 4 sparc-*-sunos4*
2530 Tsqware Sparclet sparclet-*-*
2531 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2533 *** Changes in GDB 6.0:
2537 Support for debugging the Objective-C programming language has been
2538 integrated into GDB.
2540 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2542 DWARF 2's Call Frame Information makes available compiler generated
2543 information that more exactly describes the program's run-time stack.
2544 By using this information, GDB is able to provide more robust stack
2547 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2548 have been updated to use a new backtrace mechanism which includes
2549 DWARF 2 CFI support.
2553 GDB's remote protocol has been extended to include support for hosted
2554 file I/O (where the remote target uses GDB's file system). See GDB's
2555 remote protocol documentation for details.
2557 * All targets using the new architecture framework.
2559 All of GDB's targets have been updated to use the new internal
2560 architecture framework. The way is now open for future GDB releases
2561 to include cross-architecture native debugging support (i386 on amd64,
2564 * GNU/Linux's Thread Local Storage (TLS)
2566 GDB now includes support for for the GNU/Linux implementation of
2567 per-thread variables.
2569 * GNU/Linux's Native POSIX Thread Library (NPTL)
2571 GDB's thread code has been updated to work with either the new
2572 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2574 * Separate debug info.
2576 GDB, in conjunction with BINUTILS, now supports a mechanism for
2577 automatically loading debug information from a separate file. Instead
2578 of shipping full debug and non-debug versions of system libraries,
2579 system integrators can now instead ship just the stripped libraries
2580 and optional debug files.
2582 * DWARF 2 Location Expressions
2584 DWARF 2 Location Expressions allow the compiler to more completely
2585 describe the location of variables (even in optimized code) to the
2588 GDB now includes preliminary support for location expressions (support
2589 for DW_OP_piece is still missing).
2593 A number of long standing bugs that caused GDB to die while starting a
2594 Java application have been fixed. GDB's Java support is now
2595 considered "useable".
2597 * GNU/Linux support for fork, vfork, and exec.
2599 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2600 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2603 * GDB supports logging output to a file
2605 There are two new commands, "set logging" and "show logging", which can be
2606 used to capture GDB's output to a file.
2608 * The meaning of "detach" has changed for gdbserver
2610 The "detach" command will now resume the application, as documented. To
2611 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2614 * d10v, m68hc11 `regs' command deprecated
2616 The `info registers' command has been updated so that it displays the
2617 registers using a format identical to the old `regs' command.
2621 A new command, "maint set profile on/off", has been added. This command can
2622 be used to enable or disable profiling while running GDB, to profile a
2623 session or a set of commands. In addition there is a new configure switch,
2624 "--enable-profiling", which will cause GDB to be compiled with profiling
2625 data, for more informative profiling results.
2627 * Default MI syntax changed to "mi2".
2629 The default MI (machine interface) syntax, enabled by the command line
2630 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2631 "mi1", can be enabled by specifying the option "-i=mi1".
2633 Support for the original "mi0" syntax (included in GDB 5.0) has been
2636 Fix for gdb/192: removed extraneous space when displaying frame level.
2637 Fix for gdb/672: update changelist is now output in mi list format.
2638 Fix for gdb/702: a -var-assign that updates the value now shows up
2639 in a subsequent -var-update.
2641 * New native configurations.
2643 FreeBSD/amd64 x86_64-*-freebsd*
2645 * Multi-arched targets.
2647 HP/PA HPUX11 hppa*-*-hpux*
2648 Renesas M32R/D w/simulator m32r-*-elf*
2650 * OBSOLETE configurations and files
2652 Configurations that have been declared obsolete in this release have
2653 been commented out. Unless there is activity to revive these
2654 configurations, the next release of GDB will have their sources
2655 permanently REMOVED.
2657 Z8000 simulator z8k-zilog-none or z8ksim
2658 Matsushita MN10200 w/simulator mn10200-*-*
2659 H8/500 simulator h8500-hitachi-hms or h8500hms
2660 HP/PA running BSD hppa*-*-bsd*
2661 HP/PA running OSF/1 hppa*-*-osf*
2662 HP/PA Pro target hppa*-*-pro*
2663 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2664 Sequent family i[3456]86-sequent-sysv4*
2665 i[3456]86-sequent-sysv*
2666 i[3456]86-sequent-bsd*
2667 Tsqware Sparclet sparclet-*-*
2668 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2670 * REMOVED configurations and files
2673 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2674 IBM AIX PS/2 i[3456]86-*-aix
2675 i386 running Mach 3.0 i[3456]86-*-mach3*
2676 i386 running Mach i[3456]86-*-mach*
2677 i386 running OSF/1 i[3456]86-*osf1mk*
2678 HP/Apollo 68k Family m68*-apollo*-sysv*,
2680 m68*-hp-bsd*, m68*-hp-hpux*
2681 Argonaut Risc Chip (ARC) arc-*-*
2682 Mitsubishi D30V d30v-*-*
2683 Fujitsu FR30 fr30-*-elf*
2684 OS/9000 i[34]86-*-os9k
2685 I960 with MON960 i960-*-coff
2687 * MIPS $fp behavior changed
2689 The convenience variable $fp, for the MIPS, now consistently returns
2690 the address of the current frame's base. Previously, depending on the
2691 context, $fp could refer to either $sp or the current frame's base
2692 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2693 The GNU Source-Level Debugger''.
2695 *** Changes in GDB 5.3:
2697 * GNU/Linux shared library multi-threaded performance improved.
2699 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2700 `/proc', in preference to `ptrace' for memory reads. This may result
2701 in an improvement in the start-up time of multi-threaded, shared
2702 library applications when run under GDB. One GDB user writes: ``loads
2703 shared libs like mad''.
2705 * ``gdbserver'' now supports multi-threaded applications on some targets
2707 Support for debugging multi-threaded applications which use
2708 the GNU/Linux LinuxThreads package has been added for
2709 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2710 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2712 * GDB now supports C/C++ preprocessor macros.
2714 GDB now expands preprocessor macro invocations in C/C++ expressions,
2715 and provides various commands for showing macro definitions and how
2718 The new command `macro expand EXPRESSION' expands any macro
2719 invocations in expression, and shows the result.
2721 The new command `show macro MACRO-NAME' shows the definition of the
2722 macro named MACRO-NAME, and where it was defined.
2724 Most compilers don't include information about macros in the debugging
2725 information by default. In GCC 3.1, for example, you need to compile
2726 your program with the options `-gdwarf-2 -g3'. If the macro
2727 information is present in the executable, GDB will read it.
2729 * Multi-arched targets.
2731 DEC Alpha (partial) alpha*-*-*
2732 DEC VAX (partial) vax-*-*
2734 National Semiconductor NS32000 (partial) ns32k-*-*
2735 Motorola 68000 (partial) m68k-*-*
2736 Motorola MCORE mcore-*-*
2740 Fujitsu FRV architecture added by Red Hat frv*-*-*
2743 * New native configurations
2745 Alpha NetBSD alpha*-*-netbsd*
2746 SH NetBSD sh*-*-netbsdelf*
2747 MIPS NetBSD mips*-*-netbsd*
2748 UltraSPARC NetBSD sparc64-*-netbsd*
2750 * OBSOLETE configurations and files
2752 Configurations that have been declared obsolete in this release have
2753 been commented out. Unless there is activity to revive these
2754 configurations, the next release of GDB will have their sources
2755 permanently REMOVED.
2757 Mitsubishi D30V d30v-*-*
2758 OS/9000 i[34]86-*-os9k
2759 IBM AIX PS/2 i[3456]86-*-aix
2760 Fujitsu FR30 fr30-*-elf*
2761 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2762 Argonaut Risc Chip (ARC) arc-*-*
2763 i386 running Mach 3.0 i[3456]86-*-mach3*
2764 i386 running Mach i[3456]86-*-mach*
2765 i386 running OSF/1 i[3456]86-*osf1mk*
2766 HP/Apollo 68k Family m68*-apollo*-sysv*,
2768 m68*-hp-bsd*, m68*-hp-hpux*
2769 I960 with MON960 i960-*-coff
2771 * OBSOLETE languages
2773 CHILL, a Pascal like language used by telecommunications companies.
2775 * REMOVED configurations and files
2777 AMD 29k family via UDI a29k-amd-udi, udi29k
2778 A29K VxWorks a29k-*-vxworks
2779 AMD 29000 embedded, using EBMON a29k-none-none
2780 AMD 29000 embedded with COFF a29k-none-coff
2781 AMD 29000 embedded with a.out a29k-none-aout
2783 testsuite/gdb.hp/gdb.threads-hp/ directory
2785 * New command "set max-user-call-depth <nnn>"
2787 This command allows the user to limit the call depth of user-defined
2788 commands. The default is 1024.
2790 * Changes in FreeBSD/i386 native debugging.
2792 Support for the "generate-core-file" has been added.
2794 * New commands "dump", "append", and "restore".
2796 These commands allow data to be copied from target memory
2797 to a bfd-format or binary file (dump and append), and back
2798 from a file into memory (restore).
2800 * Improved "next/step" support on multi-processor Alpha Tru64.
2802 The previous single-step mechanism could cause unpredictable problems,
2803 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2804 of a software single-step mechanism prevents this.
2806 *** Changes in GDB 5.2.1:
2814 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2815 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2816 Fix, by Joel Brobecker imported from mainline.
2818 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2819 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2820 Fix, by Fred Fish, imported from mainline.
2822 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2823 Surprisingly enough, it works now.
2824 By Michal Ludvig, imported from mainline.
2826 i386 hardware watchpoint support:
2827 avoid misses on second run for some targets.
2828 By Pierre Muller, imported from mainline.
2830 *** Changes in GDB 5.2:
2832 * New command "set trust-readonly-sections on[off]".
2834 This command is a hint that tells gdb that read-only sections
2835 really are read-only (ie. that their contents will not change).
2836 In this mode, gdb will go to the object file rather than the
2837 target to read memory from read-only sections (such as ".text").
2838 This can be a significant performance improvement on some
2839 (notably embedded) targets.
2841 * New command "generate-core-file" (or "gcore").
2843 This new gdb command allows the user to drop a core file of the child
2844 process state at any time. So far it's been implemented only for
2845 GNU/Linux and Solaris, but should be relatively easily ported to other
2846 hosts. Argument is core file name (defaults to core.<pid>).
2848 * New command line option
2850 GDB now accepts --pid or -p followed by a process id.
2852 * Change in command line behavior -- corefiles vs. process ids.
2854 There is a subtle behavior in the way in which GDB handles
2855 command line arguments. The first non-flag argument is always
2856 a program to debug, but the second non-flag argument may either
2857 be a corefile or a process id. Previously, GDB would attempt to
2858 open the second argument as a corefile, and if that failed, would
2859 issue a superfluous error message and then attempt to attach it as
2860 a process. Now, if the second argument begins with a non-digit,
2861 it will be treated as a corefile. If it begins with a digit,
2862 GDB will attempt to attach it as a process, and if no such process
2863 is found, will then attempt to open it as a corefile.
2865 * Changes in ARM configurations.
2867 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2868 configuration is fully multi-arch.
2870 * New native configurations
2872 ARM NetBSD arm*-*-netbsd*
2873 x86 OpenBSD i[3456]86-*-openbsd*
2874 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2875 Sparc64 running FreeBSD sparc64-*-freebsd*
2879 Sanyo XStormy16 xstormy16-elf
2881 * OBSOLETE configurations and files
2883 Configurations that have been declared obsolete in this release have
2884 been commented out. Unless there is activity to revive these
2885 configurations, the next release of GDB will have their sources
2886 permanently REMOVED.
2888 AMD 29k family via UDI a29k-amd-udi, udi29k
2889 A29K VxWorks a29k-*-vxworks
2890 AMD 29000 embedded, using EBMON a29k-none-none
2891 AMD 29000 embedded with COFF a29k-none-coff
2892 AMD 29000 embedded with a.out a29k-none-aout
2894 testsuite/gdb.hp/gdb.threads-hp/ directory
2896 * REMOVED configurations and files
2898 TI TMS320C80 tic80-*-*
2900 PowerPC Solaris powerpcle-*-solaris*
2901 PowerPC Windows NT powerpcle-*-cygwin32
2902 PowerPC Netware powerpc-*-netware*
2903 Harris/CXUX m88k m88*-harris-cxux*
2904 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2905 ns32k-utek-sysv* ns32k-utek-*
2906 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2907 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2908 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2909 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2910 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2912 * Changes to command line processing
2914 The new `--args' feature can be used to specify command-line arguments
2915 for the inferior from gdb's command line.
2917 * Changes to key bindings
2919 There is a new `operate-and-get-next' function bound to `C-o'.
2921 *** Changes in GDB 5.1.1
2923 Fix compile problem on DJGPP.
2925 Fix a problem with floating-point registers on the i386 being
2928 Fix to stop GDB crashing on .debug_str debug info.
2930 Numerous documentation fixes.
2932 Numerous testsuite fixes.
2934 *** Changes in GDB 5.1:
2936 * New native configurations
2938 Alpha FreeBSD alpha*-*-freebsd*
2939 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2940 MIPS GNU/Linux mips*-*-linux*
2941 MIPS SGI Irix 6.x mips*-sgi-irix6*
2942 ia64 AIX ia64-*-aix*
2943 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2947 Motorola 68HC11 and 68HC12 m68hc11-elf
2949 UltraSparc running GNU/Linux sparc64-*-linux*
2951 * OBSOLETE configurations and files
2953 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2954 Harris/CXUX m88k m88*-harris-cxux*
2955 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2956 ns32k-utek-sysv* ns32k-utek-*
2957 TI TMS320C80 tic80-*-*
2959 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2960 PowerPC Solaris powerpcle-*-solaris*
2961 PowerPC Windows NT powerpcle-*-cygwin32
2962 PowerPC Netware powerpc-*-netware*
2963 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2964 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2965 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2966 Apple Macintosh (MPW) host N/A
2968 stuff.c (Program to stuff files into a specially prepared space in kdb)
2969 kdb-start.c (Main loop for the standalone kernel debugger)
2971 Configurations that have been declared obsolete in this release have
2972 been commented out. Unless there is activity to revive these
2973 configurations, the next release of GDB will have their sources
2974 permanently REMOVED.
2976 * REMOVED configurations and files
2978 Altos 3068 m68*-altos-*
2979 Convex c1-*-*, c2-*-*
2981 ARM RISCix arm-*-* (as host)
2985 * GDB has been converted to ISO C.
2987 GDB's source code has been converted to ISO C. In particular, the
2988 sources are fully protoized, and rely on standard headers being
2993 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2995 * The MI enabled by default.
2997 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2998 revised and enabled by default. Packages which use GDB as a debugging
2999 engine behind a UI or another front end are encouraged to switch to
3000 using the GDB/MI interface, instead of the old annotations interface
3001 which is now deprecated.
3003 * Support for debugging Pascal programs.
3005 GDB now includes support for debugging Pascal programs. The following
3006 main features are supported:
3008 - Pascal-specific data types such as sets;
3010 - automatic recognition of Pascal sources based on file-name
3013 - Pascal-style display of data types, variables, and functions;
3015 - a Pascal expression parser.
3017 However, some important features are not yet supported.
3019 - Pascal string operations are not supported at all;
3021 - there are some problems with boolean types;
3023 - Pascal type hexadecimal constants are not supported
3024 because they conflict with the internal variables format;
3026 - support for Pascal objects and classes is not full yet;
3028 - unlike Pascal, GDB is case-sensitive for symbol names.
3030 * Changes in completion.
3032 Commands such as `shell', `run' and `set args', which pass arguments
3033 to inferior programs, now complete on file names, similar to what
3034 users expect at the shell prompt.
3036 Commands which accept locations, such as `disassemble', `print',
3037 `breakpoint', `until', etc. now complete on filenames as well as
3038 program symbols. Thus, if you type "break foob TAB", and the source
3039 files linked into the programs include `foobar.c', that file name will
3040 be one of the candidates for completion. However, file names are not
3041 considered for completion after you typed a colon that delimits a file
3042 name from a name of a function in that file, as in "break foo.c:bar".
3044 `set demangle-style' completes on available demangling styles.
3046 * New platform-independent commands:
3048 It is now possible to define a post-hook for a command as well as a
3049 hook that runs before the command. For more details, see the
3050 documentation of `hookpost' in the GDB manual.
3052 * Changes in GNU/Linux native debugging.
3054 Support for debugging multi-threaded programs has been completely
3055 revised for all platforms except m68k and sparc. You can now debug as
3056 many threads as your system allows you to have.
3058 Attach/detach is supported for multi-threaded programs.
3060 Support for SSE registers was added for x86. This doesn't work for
3061 multi-threaded programs though.
3063 * Changes in MIPS configurations.
3065 Multi-arch support is enabled for all MIPS configurations.
3067 GDB can now be built as native debugger on SGI Irix 6.x systems for
3068 debugging n32 executables. (Debugging 64-bit executables is not yet
3071 * Unified support for hardware watchpoints in all x86 configurations.
3073 Most (if not all) native x86 configurations support hardware-assisted
3074 breakpoints and watchpoints in a unified manner. This support
3075 implements debug register sharing between watchpoints, which allows to
3076 put a virtually infinite number of watchpoints on the same address,
3077 and also supports watching regions up to 16 bytes with several debug
3080 The new maintenance command `maintenance show-debug-regs' toggles
3081 debugging print-outs in functions that insert, remove, and test
3082 watchpoints and hardware breakpoints.
3084 * Changes in the DJGPP native configuration.
3086 New command ``info dos sysinfo'' displays assorted information about
3087 the CPU, OS, memory, and DPMI server.
3089 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3090 display information about segment descriptors stored in GDT, LDT, and
3093 New commands ``info dos pde'' and ``info dos pte'' display entries
3094 from Page Directory and Page Tables (for now works with CWSDPMI only).
3095 New command ``info dos address-pte'' displays the Page Table entry for
3096 a given linear address.
3098 GDB can now pass command lines longer than 126 characters to the
3099 program being debugged (requires an update to the libdbg.a library
3100 which is part of the DJGPP development kit).
3102 DWARF2 debug info is now supported.
3104 It is now possible to `step' and `next' through calls to `longjmp'.
3106 * Changes in documentation.
3108 All GDB documentation was converted to GFDL, the GNU Free
3109 Documentation License.
3111 Tracepoints-related commands are now fully documented in the GDB
3114 TUI, the Text-mode User Interface, is now documented in the manual.
3116 Tracepoints-related commands are now fully documented in the GDB
3119 The "GDB Internals" manual now has an index. It also includes
3120 documentation of `ui_out' functions, GDB coding standards, x86
3121 hardware watchpoints, and memory region attributes.
3123 * GDB's version number moved to ``version.in''
3125 The Makefile variable VERSION has been replaced by the file
3126 ``version.in''. People creating GDB distributions should update the
3127 contents of this file.
3131 GUD support is now a standard part of the EMACS distribution.
3133 *** Changes in GDB 5.0:
3135 * Improved support for debugging FP programs on x86 targets
3137 Unified and much-improved support for debugging floating-point
3138 programs on all x86 targets. In particular, ``info float'' now
3139 displays the FP registers in the same format on all x86 targets, with
3140 greater level of detail.
3142 * Improvements and bugfixes in hardware-assisted watchpoints
3144 It is now possible to watch array elements, struct members, and
3145 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3146 on x86 targets no longer erroneously trigger when the address is
3149 * Improvements in the native DJGPP version of GDB
3151 The distribution now includes all the scripts and auxiliary files
3152 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3153 machines ``out of the box''.
3155 The DJGPP version can now debug programs that use signals. It is
3156 possible to catch signals that happened in the debuggee, deliver
3157 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3158 would kill the program being debugged.) Programs that hook hardware
3159 interrupts (keyboard, timer, etc.) can also be debugged.
3161 It is now possible to debug DJGPP programs that redirect their
3162 standard handles or switch them to raw (as opposed to cooked) mode, or
3163 even close them. The command ``run < foo > bar'' works as expected,
3164 and ``info terminal'' reports useful information about the debuggee's
3165 terminal, including raw/cooked mode, redirection, etc.
3167 The DJGPP version now uses termios functions for console I/O, which
3168 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3171 DOS-style file names with drive letters are now fully supported by
3174 It is now possible to debug DJGPP programs that switch their working
3175 directory. It is also possible to rerun the debuggee any number of
3176 times without restarting GDB; thus, you can use the same setup,
3177 breakpoints, etc. for many debugging sessions.
3179 * New native configurations
3181 ARM GNU/Linux arm*-*-linux*
3182 PowerPC GNU/Linux powerpc-*-linux*
3186 Motorola MCore mcore-*-*
3187 x86 VxWorks i[3456]86-*-vxworks*
3188 PowerPC VxWorks powerpc-*-vxworks*
3189 TI TMS320C80 tic80-*-*
3191 * OBSOLETE configurations
3193 Altos 3068 m68*-altos-*
3194 Convex c1-*-*, c2-*-*
3196 ARM RISCix arm-*-* (as host)
3199 Configurations that have been declared obsolete will be commented out,
3200 but the code will be left in place. If there is no activity to revive
3201 these configurations before the next release of GDB, the sources will
3202 be permanently REMOVED.
3204 * Gould support removed
3206 Support for the Gould PowerNode and NP1 has been removed.
3208 * New features for SVR4
3210 On SVR4 native platforms (such as Solaris), if you attach to a process
3211 without first loading a symbol file, GDB will now attempt to locate and
3212 load symbols from the running process's executable file.
3214 * Many C++ enhancements
3216 C++ support has been greatly improved. Overload resolution now works properly
3217 in almost all cases. RTTI support is on the way.
3219 * Remote targets can connect to a sub-program
3221 A popen(3) style serial-device has been added. This device starts a
3222 sub-process (such as a stand-alone simulator) and then communicates
3223 with that. The sub-program to run is specified using the syntax
3224 ``|<program> <args>'' vis:
3226 (gdb) set remotedebug 1
3227 (gdb) target extended-remote |mn10300-elf-sim program-args
3229 * MIPS 64 remote protocol
3231 A long standing bug in the mips64 remote protocol where by GDB
3232 expected certain 32 bit registers (ex SR) to be transfered as 32
3233 instead of 64 bits has been fixed.
3235 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3236 added to provide backward compatibility with older versions of GDB.
3238 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3240 The command ``set remotebinarydownload'' command has been replaced by
3241 ``set remote X-packet''. Other commands in ``set remote'' family
3242 include ``set remote P-packet''.
3244 * Breakpoint commands accept ranges.
3246 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3247 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3248 ``tracepoint passcount'' also accepts a range of tracepoints.
3250 * ``apropos'' command added.
3252 The ``apropos'' command searches through command names and
3253 documentation strings, printing out matches, making it much easier to
3254 try to find a command that does what you are looking for.
3258 A new machine oriented interface (MI) has been added to GDB. This
3259 interface is designed for debug environments running GDB as a separate
3260 process. This is part of the long term libGDB project. See the
3261 "GDB/MI" chapter of the GDB manual for further information. It can be
3262 enabled by configuring with:
3264 .../configure --enable-gdbmi
3266 *** Changes in GDB-4.18:
3268 * New native configurations
3270 HP-UX 10.20 hppa*-*-hpux10.20
3271 HP-UX 11.x hppa*-*-hpux11.0*
3272 M68K GNU/Linux m68*-*-linux*
3276 Fujitsu FR30 fr30-*-elf*
3277 Intel StrongARM strongarm-*-*
3278 Mitsubishi D30V d30v-*-*
3280 * OBSOLETE configurations
3282 Gould PowerNode, NP1 np1-*-*, pn-*-*
3284 Configurations that have been declared obsolete will be commented out,
3285 but the code will be left in place. If there is no activity to revive
3286 these configurations before the next release of GDB, the sources will
3287 be permanently REMOVED.
3291 As a compatibility experiment, GDB's source files buildsym.h and
3292 buildsym.c have been converted to pure standard C, no longer
3293 containing any K&R compatibility code. We believe that all systems in
3294 use today either come with a standard C compiler, or have a GCC port
3295 available. If this is not true, please report the affected
3296 configuration to bug-gdb@gnu.org immediately. See the README file for
3297 information about getting a standard C compiler if you don't have one
3302 GDB now uses readline 2.2.
3304 * set extension-language
3306 You can now control the mapping between filename extensions and source
3307 languages by using the `set extension-language' command. For instance,
3308 you can ask GDB to treat .c files as C++ by saying
3309 set extension-language .c c++
3310 The command `info extensions' lists all of the recognized extensions
3311 and their associated languages.
3313 * Setting processor type for PowerPC and RS/6000
3315 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3316 you can use the `set processor' command to specify what variant of the
3317 PowerPC family you are debugging. The command
3321 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3322 following PowerPC and RS6000 variants:
3324 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3325 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3327 403GC IBM PowerPC 403GC
3328 505 Motorola PowerPC 505
3329 860 Motorola PowerPC 860 or 850
3330 601 Motorola PowerPC 601
3331 602 Motorola PowerPC 602
3332 603 Motorola/IBM PowerPC 603 or 603e
3333 604 Motorola PowerPC 604 or 604e
3334 750 Motorola/IBM PowerPC 750 or 750
3336 At the moment, this command just tells GDB what to name the
3337 special-purpose processor registers. Since almost all the affected
3338 registers are inaccessible to user-level programs, this command is
3339 only useful for remote debugging in its present form.
3343 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3344 more extensive support for HP-UX. Added features include shared
3345 library support, kernel threads and hardware watchpoints for 11.00,
3346 support for HP's ANSI C and C++ compilers, and a compatibility mode
3347 for xdb and dbx commands.
3351 HP's donation includes the new concept of catchpoints, which is a
3352 generalization of the old catch command. On HP-UX, it is now possible
3353 to catch exec, fork, and vfork, as well as library loading.
3355 This means that the existing catch command has changed; its first
3356 argument now specifies the type of catch to be set up. See the
3357 output of "help catch" for a list of catchpoint types.
3359 * Debugging across forks
3361 On HP-UX, you can choose which process to debug when a fork() happens
3366 HP has donated a curses-based terminal user interface (TUI). To get
3367 it, build with --enable-tui. Although this can be enabled for any
3368 configuration, at present it only works for native HP debugging.
3370 * GDB remote protocol additions
3372 A new protocol packet 'X' that writes binary data is now available.
3373 Default behavior is to try 'X', then drop back to 'M' if the stub
3374 fails to respond. The settable variable `remotebinarydownload'
3375 allows explicit control over the use of 'X'.
3377 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3378 full 64-bit address. The command
3380 set remoteaddresssize 32
3382 can be used to revert to the old behaviour. For existing remote stubs
3383 the change should not be noticed, as the additional address information
3386 In order to assist in debugging stubs, you may use the maintenance
3387 command `packet' to send any text string to the stub. For instance,
3389 maint packet heythere
3391 sends the packet "$heythere#<checksum>". Note that it is very easy to
3392 disrupt a debugging session by sending the wrong packet at the wrong
3395 The compare-sections command allows you to compare section data on the
3396 target to what is in the executable file without uploading or
3397 downloading, by comparing CRC checksums.
3399 * Tracing can collect general expressions
3401 You may now collect general expressions at tracepoints. This requires
3402 further additions to the target-side stub; see tracepoint.c and
3403 doc/agentexpr.texi for further details.
3405 * mask-address variable for Mips
3407 For Mips targets, you may control the zeroing of the upper 32 bits of
3408 a 64-bit address by entering `set mask-address on'. This is mainly
3409 of interest to users of embedded R4xxx and R5xxx processors.
3411 * Higher serial baud rates
3413 GDB's serial code now allows you to specify baud rates 57600, 115200,
3414 230400, and 460800 baud. (Note that your host system may not be able
3415 to achieve all of these rates.)
3419 The i960 configuration now includes an initial implementation of a
3420 builtin simulator, contributed by Jim Wilson.
3423 *** Changes in GDB-4.17:
3425 * New native configurations
3427 Alpha GNU/Linux alpha*-*-linux*
3428 Unixware 2.x i[3456]86-unixware2*
3429 Irix 6.x mips*-sgi-irix6*
3430 PowerPC GNU/Linux powerpc-*-linux*
3431 PowerPC Solaris powerpcle-*-solaris*
3432 Sparc GNU/Linux sparc-*-linux*
3433 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3437 Argonaut Risc Chip (ARC) arc-*-*
3438 Hitachi H8/300S h8300*-*-*
3439 Matsushita MN10200 w/simulator mn10200-*-*
3440 Matsushita MN10300 w/simulator mn10300-*-*
3441 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3442 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3443 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3444 Mitsubishi D10V w/simulator d10v-*-*
3445 Mitsubishi M32R/D w/simulator m32r-*-elf*
3446 Tsqware Sparclet sparclet-*-*
3447 NEC V850 w/simulator v850-*-*
3449 * New debugging protocols
3451 ARM with RDI protocol arm*-*-*
3452 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3453 DDB and LSI variants of PMON protocol mips*-*-*
3454 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3455 PowerPC with SDS protocol powerpc{,le}-*-eabi
3456 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3460 All configurations can now understand and use the DWARF 2 debugging
3461 format. The choice is automatic, if the symbol file contains DWARF 2
3466 GDB now includes basic Java language support. This support is
3467 only useful with Java compilers that produce native machine code.
3469 * solib-absolute-prefix and solib-search-path
3471 For SunOS and SVR4 shared libraries, you may now set the prefix for
3472 loading absolute shared library symbol files, and the search path for
3473 locating non-absolute shared library symbol files.
3475 * Live range splitting
3477 GDB can now effectively debug code for which GCC has performed live
3478 range splitting as part of its optimization. See gdb/doc/LRS for
3479 more details on the expected format of the stabs information.
3483 GDB's support for the GNU Hurd, including thread debugging, has been
3484 updated to work with current versions of the Hurd.
3488 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3489 instruction set. ARM GDB automatically detects when Thumb
3490 instructions are in use, and adjusts disassembly and backtracing
3495 GDB's MIPS target configurations now handle the MIP16 16-bit
3500 GDB now includes support for overlays; if an executable has been
3501 linked such that multiple sections are based at the same address, GDB
3502 will decide which section to use for symbolic info. You can choose to
3503 control the decision manually, using overlay commands, or implement
3504 additional target-side support and use "overlay load-target" to bring
3505 in the overlay mapping. Do "help overlay" for more detail.
3509 The command "info symbol <address>" displays information about
3510 the symbol at the specified address.
3514 The standard remote protocol now includes an extension that allows
3515 asynchronous collection and display of trace data. This requires
3516 extensive support in the target-side debugging stub. Tracing mode
3517 includes a new interaction mode in GDB and new commands: see the
3518 file tracepoint.c for more details.
3522 Configurations for embedded MIPS now include a simulator contributed
3523 by Cygnus Solutions. The simulator supports the instruction sets
3524 of most MIPS variants.
3528 Sparc configurations may now include the ERC32 simulator contributed
3529 by the European Space Agency. The simulator is not built into
3530 Sparc targets by default; configure with --enable-sim to include it.
3534 For target configurations that may include multiple variants of a
3535 basic architecture (such as MIPS and SH), you may now set the
3536 architecture explicitly. "set arch" sets, "info arch" lists
3537 the possible architectures.
3539 *** Changes in GDB-4.16:
3541 * New native configurations
3543 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3544 M68K NetBSD m68k-*-netbsd*
3545 PowerPC AIX 4.x powerpc-*-aix*
3546 PowerPC MacOS powerpc-*-macos*
3547 PowerPC Windows NT powerpcle-*-cygwin32
3548 RS/6000 AIX 4.x rs6000-*-aix4*
3552 ARM with RDP protocol arm-*-*
3553 I960 with MON960 i960-*-coff
3554 MIPS VxWorks mips*-*-vxworks*
3555 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3556 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3558 Matra Sparclet sparclet-*-*
3562 The powerpc-eabi configuration now includes the PSIM simulator,
3563 contributed by Andrew Cagney, with assistance from Mike Meissner.
3564 PSIM is a very elaborate model of the PowerPC, including not only
3565 basic instruction set execution, but also details of execution unit
3566 performance and I/O hardware. See sim/ppc/README for more details.
3570 GDB now works with Solaris 2.5.
3572 * Windows 95/NT native
3574 GDB will now work as a native debugger on Windows 95 and Windows NT.
3575 To build it from source, you must use the "gnu-win32" environment,
3576 which uses a DLL to emulate enough of Unix to run the GNU tools.
3577 Further information, binaries, and sources are available at
3578 ftp.cygnus.com, under pub/gnu-win32.
3580 * dont-repeat command
3582 If a user-defined command includes the command `dont-repeat', then the
3583 command will not be repeated if the user just types return. This is
3584 useful if the command is time-consuming to run, so that accidental
3585 extra keystrokes don't run the same command many times.
3587 * Send break instead of ^C
3589 The standard remote protocol now includes an option to send a break
3590 rather than a ^C to the target in order to interrupt it. By default,
3591 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3593 * Remote protocol timeout
3595 The standard remote protocol includes a new variable `remotetimeout'
3596 that allows you to set the number of seconds before GDB gives up trying
3597 to read from the target. The default value is 2.
3599 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3601 By default GDB will automatically keep track of objects as they are
3602 loaded and unloaded by the dynamic linker. By using the command `set
3603 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3604 when shared library events occur, thus allowing you to set breakpoints
3605 in shared libraries which are explicitly loaded by the inferior.
3607 Note this feature does not work on hpux8. On hpux9 you must link
3608 /usr/lib/end.o into your program. This feature should work
3609 automatically on hpux10.
3611 * Irix 5.x hardware watchpoint support
3613 Irix 5 configurations now support the use of hardware watchpoints.
3615 * Mips protocol "SYN garbage limit"
3617 When debugging a Mips target using the `target mips' protocol, you
3618 may set the number of characters that GDB will ignore by setting
3619 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3620 every character. The default value is 1050.
3622 * Recording and replaying remote debug sessions
3624 If you set `remotelogfile' to the name of a file, gdb will write to it
3625 a recording of a remote debug session. This recording may then be
3626 replayed back to gdb using "gdbreplay". See gdbserver/README for
3627 details. This is useful when you have a problem with GDB while doing
3628 remote debugging; you can make a recording of the session and send it
3629 to someone else, who can then recreate the problem.
3631 * Speedups for remote debugging
3633 GDB includes speedups for downloading and stepping MIPS systems using
3634 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3635 and more efficient S-record downloading.
3637 * Memory use reductions and statistics collection
3639 GDB now uses less memory and reports statistics about memory usage.
3640 Try the `maint print statistics' command, for example.
3642 *** Changes in GDB-4.15:
3644 * Psymtabs for XCOFF
3646 The symbol reader for AIX GDB now uses partial symbol tables. This
3647 can greatly improve startup time, especially for large executables.
3649 * Remote targets use caching
3651 Remote targets now use a data cache to speed up communication with the
3652 remote side. The data cache could lead to incorrect results because
3653 it doesn't know about volatile variables, thus making it impossible to
3654 debug targets which use memory mapped I/O devices. `set remotecache
3655 off' turns the the data cache off.
3657 * Remote targets may have threads
3659 The standard remote protocol now includes support for multiple threads
3660 in the target system, using new protocol commands 'H' and 'T'. See
3661 gdb/remote.c for details.
3665 If GDB is configured with `--enable-netrom', then it will include
3666 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3667 acts as though it is a bank of ROM on the target board, but you can
3668 write into it over the network. GDB's support consists only of
3669 support for fast loading into the emulated ROM; to debug, you must use
3670 another protocol, such as standard remote protocol. The usual
3671 sequence is something like
3673 target nrom <netrom-hostname>
3675 target remote <netrom-hostname>:1235
3679 GDB now includes support for the Apple Macintosh, as a host only. It
3680 may be run as either an MPW tool or as a standalone application, and
3681 it can debug through the serial port. All the usual GDB commands are
3682 available, but to the target command, you must supply "serial" as the
3683 device type instead of "/dev/ttyXX". See mpw-README in the main
3684 directory for more information on how to build. The MPW configuration
3685 scripts */mpw-config.in support only a few targets, and only the
3686 mips-idt-ecoff target has been tested.
3690 GDB configuration now uses autoconf. This is not user-visible,
3691 but does simplify configuration and building.
3695 GDB now supports hpux10.
3697 *** Changes in GDB-4.14:
3699 * New native configurations
3701 x86 FreeBSD i[345]86-*-freebsd
3702 x86 NetBSD i[345]86-*-netbsd
3703 NS32k NetBSD ns32k-*-netbsd
3704 Sparc NetBSD sparc-*-netbsd
3708 A29K VxWorks a29k-*-vxworks
3709 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3710 CPU32 EST-300 emulator m68*-*-est*
3711 PowerPC ELF powerpc-*-elf
3714 * Alpha OSF/1 support for procfs
3716 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3717 possible to attach to running processes. As the mounting of the /proc
3718 filesystem is optional on the Alpha, GDB automatically determines
3719 the availability of /proc during startup. This can lead to problems
3720 if /proc is unmounted after GDB has been started.
3722 * Arguments to user-defined commands
3724 User commands may accept up to 10 arguments separated by whitespace.
3725 Arguments are accessed within the user command via $arg0..$arg9. A
3728 print $arg0 + $arg1 + $arg2
3730 To execute the command use:
3733 Defines the command "adder" which prints the sum of its three arguments.
3734 Note the arguments are text substitutions, so they may reference variables,
3735 use complex expressions, or even perform inferior function calls.
3737 * New `if' and `while' commands
3739 This makes it possible to write more sophisticated user-defined
3740 commands. Both commands take a single argument, which is the
3741 expression to evaluate, and must be followed by the commands to
3742 execute, one per line, if the expression is nonzero, the list being
3743 terminated by the word `end'. The `if' command list may include an
3744 `else' word, which causes the following commands to be executed only
3745 if the expression is zero.
3747 * Fortran source language mode
3749 GDB now includes partial support for Fortran 77. It will recognize
3750 Fortran programs and can evaluate a subset of Fortran expressions, but
3751 variables and functions may not be handled correctly. GDB will work
3752 with G77, but does not yet know much about symbols emitted by other
3755 * Better HPUX support
3757 Most debugging facilities now work on dynamic executables for HPPAs
3758 running hpux9 or later. You can attach to running dynamically linked
3759 processes, but by default the dynamic libraries will be read-only, so
3760 for instance you won't be able to put breakpoints in them. To change
3761 that behavior do the following before running the program:
3767 This will cause the libraries to be mapped private and read-write.
3768 To revert to the normal behavior, do this:
3774 You cannot set breakpoints or examine data in the library until after
3775 the library is loaded if the function/data symbols do not have
3778 GDB can now also read debug symbols produced by the HP C compiler on
3779 HPPAs (sorry, no C++, Fortran or 68k support).
3781 * Target byte order now dynamically selectable
3783 You can choose which byte order to use with a target system, via the
3784 commands "set endian big" and "set endian little", and you can see the
3785 current setting by using "show endian". You can also give the command
3786 "set endian auto", in which case GDB will use the byte order
3787 associated with the executable. Currently, only embedded MIPS
3788 configurations support dynamic selection of target byte order.
3790 * New DOS host serial code
3792 This version uses DPMI interrupts to handle buffered I/O, so you
3793 no longer need to run asynctsr when debugging boards connected to
3796 *** Changes in GDB-4.13:
3798 * New "complete" command
3800 This lists all the possible completions for the rest of the line, if it
3801 were to be given as a command itself. This is intended for use by emacs.
3803 * Trailing space optional in prompt
3805 "set prompt" no longer adds a space for you after the prompt you set. This
3806 allows you to set a prompt which ends in a space or one that does not.
3808 * Breakpoint hit counts
3810 "info break" now displays a count of the number of times the breakpoint
3811 has been hit. This is especially useful in conjunction with "ignore"; you
3812 can ignore a large number of breakpoint hits, look at the breakpoint info
3813 to see how many times the breakpoint was hit, then run again, ignoring one
3814 less than that number, and this will get you quickly to the last hit of
3817 * Ability to stop printing at NULL character
3819 "set print null-stop" will cause GDB to stop printing the characters of
3820 an array when the first NULL is encountered. This is useful when large
3821 arrays actually contain only short strings.
3823 * Shared library breakpoints
3825 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3826 breakpoints in shared libraries before the executable is run.
3828 * Hardware watchpoints
3830 There is a new hardware breakpoint for the watch command for sparclite
3831 targets. See gdb/sparclite/hw_breakpoint.note.
3833 Hardware watchpoints are also now supported under GNU/Linux.
3837 Annotations have been added. These are for use with graphical interfaces,
3838 and are still experimental. Currently only gdba.el uses these.
3840 * Improved Irix 5 support
3842 GDB now works properly with Irix 5.2.
3844 * Improved HPPA support
3846 GDB now works properly with the latest GCC and GAS.
3848 * New native configurations
3850 Sequent PTX4 i[34]86-sequent-ptx4
3851 HPPA running OSF/1 hppa*-*-osf*
3852 Atari TT running SVR4 m68*-*-sysv4*
3853 RS/6000 LynxOS rs6000-*-lynxos*
3857 OS/9000 i[34]86-*-os9k
3858 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3861 * Hitachi SH7000 and E7000-PC ICE support
3863 There is now support for communicating with the Hitachi E7000-PC ICE.
3864 This is available automatically when GDB is configured for the SH.
3868 As usual, a variety of small fixes and improvements, both generic
3869 and configuration-specific. See the ChangeLog for more detail.
3871 *** Changes in GDB-4.12:
3873 * Irix 5 is now supported
3877 GDB-4.12 on the HPPA has a number of changes which make it unable
3878 to debug the output from the currently released versions of GCC and
3879 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3880 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3881 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3884 *** Changes in GDB-4.11:
3886 * User visible changes:
3890 The "set remotedebug" option is now consistent between the mips remote
3891 target, remote targets using the gdb-specific protocol, UDI (AMD's
3892 debug protocol for the 29k) and the 88k bug monitor. It is now an
3893 integer specifying a debug level (normally 0 or 1, but 2 means more
3894 debugging info for the mips target).
3896 * DEC Alpha native support
3898 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3899 debug info, but GDB works fairly well with the DEC compiler and should
3900 work with a future GCC release. See the README file for a few
3901 Alpha-specific notes.
3903 * Preliminary thread implementation
3905 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3907 * LynxOS native and target support for 386
3909 This release has been hosted on LynxOS 2.2, and also can be configured
3910 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3913 * Improvements in C++ mangling/demangling.
3915 This release has much better g++ debugging, specifically in name
3916 mangling/demangling, virtual function calls, print virtual table,
3917 call methods, ...etc.
3919 *** Changes in GDB-4.10:
3921 * User visible changes:
3923 Remote debugging using the GDB-specific (`target remote') protocol now
3924 supports the `load' command. This is only useful if you have some
3925 other way of getting the stub to the target system, and you can put it
3926 somewhere in memory where it won't get clobbered by the download.
3928 Filename completion now works.
3930 When run under emacs mode, the "info line" command now causes the
3931 arrow to point to the line specified. Also, "info line" prints
3932 addresses in symbolic form (as well as hex).
3934 All vxworks based targets now support a user settable option, called
3935 vxworks-timeout. This option represents the number of seconds gdb
3936 should wait for responses to rpc's. You might want to use this if
3937 your vxworks target is, perhaps, a slow software simulator or happens
3938 to be on the far side of a thin network line.
3942 This release contains support for using a DEC alpha as a GDB host for
3943 cross debugging. Native alpha debugging is not supported yet.
3946 *** Changes in GDB-4.9:
3950 This is the first GDB release which is accompanied by a matching testsuite.
3951 The testsuite requires installation of dejagnu, which should be available
3952 via ftp from most sites that carry GNU software.
3956 'Cfront' style demangling has had its name changed to 'ARM' style, to
3957 emphasize that it was written from the specifications in the C++ Annotated
3958 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3959 disclaimers, it still generated too much confusion with users attempting to
3960 use gdb with AT&T cfront.
3964 GDB now uses a standard remote interface to a simulator library.
3965 So far, the library contains simulators for the Zilog Z8001/2, the
3966 Hitachi H8/300, H8/500 and Super-H.
3968 * New targets supported
3970 H8/300 simulator h8300-hitachi-hms or h8300hms
3971 H8/500 simulator h8500-hitachi-hms or h8500hms
3972 SH simulator sh-hitachi-hms or sh
3973 Z8000 simulator z8k-zilog-none or z8ksim
3974 IDT MIPS board over serial line mips-idt-ecoff
3976 Cross-debugging to GO32 targets is supported. It requires a custom
3977 version of the i386-stub.c module which is integrated with the
3978 GO32 memory extender.
3980 * New remote protocols
3982 MIPS remote debugging protocol.
3984 * New source languages supported
3986 This version includes preliminary support for Chill, a Pascal like language
3987 used by telecommunications companies. Chill support is also being integrated
3988 into the GNU compiler, but we don't know when it will be publically available.
3991 *** Changes in GDB-4.8:
3993 * HP Precision Architecture supported
3995 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3996 version of this support was available as a set of patches from the
3997 University of Utah. GDB does not support debugging of programs
3998 compiled with the HP compiler, because HP will not document their file
3999 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4000 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4002 Many problems in the preliminary version have been fixed.
4004 * Faster and better demangling
4006 We have improved template demangling and fixed numerous bugs in the GNU style
4007 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4008 character types (wchar_t) are now supported. Demangling of each symbol is now
4009 only done once, and is cached when the symbol table for a file is read in.
4010 This results in a small increase in memory usage for C programs, a moderate
4011 increase in memory usage for C++ programs, and a fantastic speedup in
4014 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4015 from the specifications in the Annotated Reference Manual, which AT&T's
4016 compiler does not actually implement.
4018 * G++ multiple inheritance compiler problem
4020 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4021 inheritance lattices was reworked to properly discover ambiguities. We
4022 recently found an example which causes this new algorithm to fail in a
4023 very subtle way, producing bad debug information for those classes.
4024 The file 'gcc.patch' (in this directory) can be applied to gcc to
4025 circumvent the problem. A future GCC release will contain a complete
4028 The previous G++ debug info problem (mentioned below for the gdb-4.7
4029 release) is fixed in gcc version 2.3.2.
4031 * Improved configure script
4033 The `configure' script will now attempt to guess your system type if
4034 you don't supply a host system type. The old scheme of supplying a
4035 host system triplet is preferable over using this. All the magic is
4036 done in the new `config.guess' script. Examine it for details.
4038 We have also brought our configure script much more in line with the FSF's
4039 version. It now supports the --with-xxx options. In particular,
4040 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4041 The resulting GDB will not be able to read arbitrary object file formats --
4042 only the format ``expected'' to be used on the configured target system.
4043 We hope to make this the default in a future release.
4045 * Documentation improvements
4047 There's new internal documentation on how to modify GDB, and how to
4048 produce clean changes to the code. We implore people to read it
4049 before submitting changes.
4051 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4052 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4053 `info' files are also provided. To build `info' files from scratch,
4054 you will need the latest `makeinfo' release, which will be available in
4055 a future texinfo-X.Y release.
4057 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4058 We're not sure exactly which versions have this problem, but it has
4059 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4060 or better. If that isn't possible, there is a patch in
4061 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4062 around this problem.
4066 GDB now supports array constants that can be used in expressions typed in by
4067 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4068 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4071 The new directory `gdb/sparclite' contains a program that demonstrates
4072 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4074 * New native hosts supported
4076 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4077 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4079 * New targets supported
4081 AMD 29k family via UDI a29k-amd-udi or udi29k
4083 * New file formats supported
4085 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4086 HPUX core files, and SCO 3.2v2 core files.
4090 Attaching to processes now works again; thanks for the many bug reports.
4092 We have also stomped on a bunch of core dumps caused by
4093 printf_filtered("%s") problems.
4095 We eliminated a copyright problem on the rpc and ptrace header files
4096 for VxWorks, which was discovered at the last minute during the 4.7
4097 release. You should now be able to build a VxWorks GDB.
4099 You can now interrupt gdb while an attached process is running. This
4100 will cause the attached process to stop, and give control back to GDB.
4102 We fixed problems caused by using too many file descriptors
4103 for reading symbols from object files and libraries. This was
4104 especially a problem for programs that used many (~100) shared
4107 The `step' command now only enters a subroutine if there is line number
4108 information for the subroutine. Otherwise it acts like the `next'
4109 command. Previously, `step' would enter subroutines if there was
4110 any debugging information about the routine. This avoids problems
4111 when using `cc -g1' on MIPS machines.
4113 * Internal improvements
4115 GDB's internal interfaces have been improved to make it easier to support
4116 debugging of multiple languages in the future.
4118 GDB now uses a common structure for symbol information internally.
4119 Minimal symbols (derived from linkage symbols in object files), partial
4120 symbols (from a quick scan of debug information), and full symbols
4121 contain a common subset of information, making it easier to write
4122 shared code that handles any of them.
4124 * New command line options
4126 We now accept --silent as an alias for --quiet.
4130 The memory-mapped-malloc library is now licensed under the GNU Library
4131 General Public License.
4133 *** Changes in GDB-4.7:
4135 * Host/native/target split
4137 GDB has had some major internal surgery to untangle the support for
4138 hosts and remote targets. Now, when you configure GDB for a remote
4139 target, it will no longer load in all of the support for debugging
4140 local programs on the host. When fully completed and tested, this will
4141 ensure that arbitrary host/target combinations are possible.
4143 The primary conceptual shift is to separate the non-portable code in
4144 GDB into three categories. Host specific code is required any time GDB
4145 is compiled on that host, regardless of the target. Target specific
4146 code relates to the peculiarities of the target, but can be compiled on
4147 any host. Native specific code is everything else: it can only be
4148 built when the host and target are the same system. Child process
4149 handling and core file support are two common `native' examples.
4151 GDB's use of /proc for controlling Unix child processes is now cleaner.
4152 It has been split out into a single module under the `target_ops' vector,
4153 plus two native-dependent functions for each system that uses /proc.
4155 * New hosts supported
4157 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4158 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4159 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4161 * New targets supported
4163 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4164 68030 and CPU32 m68030-*-*, m68332-*-*
4166 * New native hosts supported
4168 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4169 (386bsd is not well tested yet)
4170 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4172 * New file formats supported
4174 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4175 supports reading of `a.out.adobe' object files, which are an a.out
4176 format extended with minimal information about multiple sections.
4180 `show copying' is the same as the old `info copying'.
4181 `show warranty' is the same as `info warrantee'.
4182 These were renamed for consistency. The old commands continue to work.
4184 `info handle' is a new alias for `info signals'.
4186 You can now define pre-command hooks, which attach arbitrary command
4187 scripts to any command. The commands in the hook will be executed
4188 prior to the user's command. You can also create a hook which will be
4189 executed whenever the program stops. See gdb.texinfo.
4193 We now deal with Cfront style name mangling, and can even extract type
4194 info from mangled symbols. GDB can automatically figure out which
4195 symbol mangling style your C++ compiler uses.
4197 Calling of methods and virtual functions has been improved as well.
4201 The crash that occured when debugging Sun Ansi-C compiled binaries is
4202 fixed. This was due to mishandling of the extra N_SO stabs output
4205 We also finally got Ultrix 4.2 running in house, and fixed core file
4206 support, with help from a dozen people on the net.
4208 John M. Farrell discovered that the reason that single-stepping was so
4209 slow on all of the Mips based platforms (primarily SGI and DEC) was
4210 that we were trying to demangle and lookup a symbol used for internal
4211 purposes on every instruction that was being stepped through. Changing
4212 the name of that symbol so that it couldn't be mistaken for a C++
4213 mangled symbol sped things up a great deal.
4215 Rich Pixley sped up symbol lookups in general by getting much smarter
4216 about when C++ symbol mangling is necessary. This should make symbol
4217 completion (TAB on the command line) much faster. It's not as fast as
4218 we'd like, but it's significantly faster than gdb-4.6.
4222 A new user controllable variable 'call_scratch_address' can
4223 specify the location of a scratch area to be used when GDB
4224 calls a function in the target. This is necessary because the
4225 usual method of putting the scratch area on the stack does not work
4226 in systems that have separate instruction and data spaces.
4228 We integrated changes to support the 29k UDI (Universal Debugger
4229 Interface), but discovered at the last minute that we didn't have all
4230 of the appropriate copyright paperwork. We are working with AMD to
4231 resolve this, and hope to have it available soon.
4235 We have sped up the remote serial line protocol, especially for targets
4236 with lots of registers. It now supports a new `expedited status' ('T')
4237 message which can be used in place of the existing 'S' status message.
4238 This allows the remote stub to send only the registers that GDB
4239 needs to make a quick decision about single-stepping or conditional
4240 breakpoints, eliminating the need to fetch the entire register set for
4241 each instruction being stepped through.
4243 The GDB remote serial protocol now implements a write-through cache for
4244 registers, only re-reading the registers if the target has run.
4246 There is also a new remote serial stub for SPARC processors. You can
4247 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4248 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4249 processor with a serial port.
4253 Configure.in files have become much easier to read and modify. A new
4254 `table driven' format makes it more obvious what configurations are
4255 supported, and what files each one uses.
4259 There is a new opcodes library which will eventually contain all of the
4260 disassembly routines and opcode tables. At present, it only contains
4261 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4262 disassembler (binutils/objdump) to share these routines.
4264 The libiberty library is now copylefted under the GNU Library General
4265 Public License. This allows more liberal use, and was done so libg++
4266 can use it. This makes no difference to GDB, since the Library License
4267 grants all the rights from the General Public License.
4271 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4272 reference to the stabs symbol info used by the debugger. It is (as far
4273 as we know) the only published document on this fascinating topic. We
4274 encourage you to read it, compare it to the stabs information on your
4275 system, and send improvements on the document in general (to
4276 bug-gdb@prep.ai.mit.edu).
4278 And, of course, many bugs have been fixed.
4281 *** Changes in GDB-4.6:
4283 * Better support for C++ function names
4285 GDB now accepts as input the "demangled form" of C++ overloaded function
4286 names and member function names, and can do command completion on such names
4287 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4288 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4289 Make use of command completion, it is your friend.
4291 GDB also now accepts a variety of C++ mangled symbol formats. They are
4292 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4293 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4294 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4295 for the list of formats.
4297 * G++ symbol mangling problem
4299 Recent versions of gcc have a bug in how they emit debugging information for
4300 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4301 directory) can be applied to gcc to fix the problem. Alternatively, if you
4302 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4303 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4304 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4307 * New 'maintenance' command
4309 All of the commands related to hacking GDB internals have been moved out of
4310 the main command set, and now live behind the 'maintenance' command. This
4311 can also be abbreviated as 'mt'. The following changes were made:
4313 dump-me -> maintenance dump-me
4314 info all-breakpoints -> maintenance info breakpoints
4315 printmsyms -> maintenance print msyms
4316 printobjfiles -> maintenance print objfiles
4317 printpsyms -> maintenance print psymbols
4318 printsyms -> maintenance print symbols
4320 The following commands are new:
4322 maintenance demangle Call internal GDB demangler routine to
4323 demangle a C++ link name and prints the result.
4324 maintenance print type Print a type chain for a given symbol
4326 * Change to .gdbinit file processing
4328 We now read the $HOME/.gdbinit file before processing the argv arguments
4329 (e.g. reading symbol files or core files). This allows global parameters to
4330 be set, which will apply during the symbol reading. The ./.gdbinit is still
4331 read after argv processing.
4333 * New hosts supported
4335 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4337 GNU/Linux support i386-unknown-linux or linux
4339 We are also including code to support the HP/PA running BSD and HPUX. This
4340 is almost guaranteed not to work, as we didn't have time to test or build it
4341 for this release. We are including it so that the more adventurous (or
4342 masochistic) of you can play with it. We also had major problems with the
4343 fact that the compiler that we got from HP doesn't support the -g option.
4346 * New targets supported
4348 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4350 * More smarts about finding #include files
4352 GDB now remembers the compilation directory for all include files, and for
4353 all files from which C is generated (like yacc and lex sources). This
4354 greatly improves GDB's ability to find yacc/lex sources, and include files,
4355 especially if you are debugging your program from a directory different from
4356 the one that contains your sources.
4358 We also fixed a bug which caused difficulty with listing and setting
4359 breakpoints in include files which contain C code. (In the past, you had to
4360 try twice in order to list an include file that you hadn't looked at before.)
4362 * Interesting infernals change
4364 GDB now deals with arbitrary numbers of sections, where the symbols for each
4365 section must be relocated relative to that section's landing place in the
4366 target's address space. This work was needed to support ELF with embedded
4367 stabs used by Solaris-2.0.
4369 * Bug fixes (of course!)
4371 There have been loads of fixes for the following things:
4372 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4373 i960, stabs, DOS(GO32), procfs, etc...
4375 See the ChangeLog for details.
4377 *** Changes in GDB-4.5:
4379 * New machines supported (host and target)
4381 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4383 SGI Irix-4.x mips-sgi-irix4 or iris4
4385 * New malloc package
4387 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4388 Mmalloc is capable of handling mutiple heaps of memory. It is also
4389 capable of saving a heap to a file, and then mapping it back in later.
4390 This can be used to greatly speedup the startup of GDB by using a
4391 pre-parsed symbol table which lives in a mmalloc managed heap. For
4392 more details, please read mmalloc/mmalloc.texi.
4396 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4397 'help info proc' for details.
4399 * MIPS ecoff symbol table format
4401 The code that reads MIPS symbol table format is now supported on all hosts.
4402 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4405 * File name changes for MS-DOS
4407 Many files in the config directories have been renamed to make it easier to
4408 support GDB on MS-DOSe systems (which have very restrictive file name
4409 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4410 environment) is close to working but has some remaining problems. Note
4411 that debugging of DOS programs is not supported, due to limitations
4412 in the ``operating system'', but it can be used to host cross-debugging.
4414 * Cross byte order fixes
4416 Many fixes have been made to support cross debugging of Sparc and MIPS
4417 targets from hosts whose byte order differs.
4419 * New -mapped and -readnow options
4421 If memory-mapped files are available on your system through the 'mmap'
4422 system call, you can use the -mapped option on the `file' or
4423 `symbol-file' commands to cause GDB to write the symbols from your
4424 program into a reusable file. If the program you are debugging is
4425 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4426 Future GDB debugging sessions will notice the presence of this file,
4427 and will quickly map in symbol information from it, rather than reading
4428 the symbol table from the executable program. Using the '-mapped'
4429 option in a GDB `file' or `symbol-file' command has the same effect as
4430 starting GDB with the '-mapped' command-line option.
4432 You can cause GDB to read the entire symbol table immediately by using
4433 the '-readnow' option with any of the commands that load symbol table
4434 information (or on the GDB command line). This makes the command
4435 slower, but makes future operations faster.
4437 The -mapped and -readnow options are typically combined in order to
4438 build a `fred.syms' file that contains complete symbol information.
4439 A simple GDB invocation to do nothing but build a `.syms' file for future
4442 gdb -batch -nx -mapped -readnow programname
4444 The `.syms' file is specific to the host machine on which GDB is run.
4445 It holds an exact image of GDB's internal symbol table. It cannot be
4446 shared across multiple host platforms.
4448 * longjmp() handling
4450 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4451 siglongjmp() without losing control. This feature has not yet been ported to
4452 all systems. It currently works on many 386 platforms, all MIPS-based
4453 platforms (SGI, DECstation, etc), and Sun3/4.
4457 Preliminary work has been put in to support the new Solaris OS from Sun. At
4458 this time, it can control and debug processes, but it is not capable of
4463 As always, many many bug fixes. The major areas were with g++, and mipsread.
4464 People using the MIPS-based platforms should experience fewer mysterious
4465 crashes and trashed symbol tables.
4467 *** Changes in GDB-4.4:
4469 * New machines supported (host and target)
4471 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4473 BSD Reno on Vax vax-dec-bsd
4474 Ultrix on Vax vax-dec-ultrix
4476 * New machines supported (target)
4478 AMD 29000 embedded, using EBMON a29k-none-none
4482 GDB continues to improve its handling of C++. `References' work better.
4483 The demangler has also been improved, and now deals with symbols mangled as
4484 per the Annotated C++ Reference Guide.
4486 GDB also now handles `stabs' symbol information embedded in MIPS
4487 `ecoff' symbol tables. Since the ecoff format was not easily
4488 extensible to handle new languages such as C++, this appeared to be a
4489 good way to put C++ debugging info into MIPS binaries. This option
4490 will be supported in the GNU C compiler, version 2, when it is
4493 * New features for SVR4
4495 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4496 shared libraries. Debugging dynamically linked programs should present
4497 only minor differences from debugging statically linked programs.
4499 The `info proc' command will print out information about any process
4500 on an SVR4 system (including the one you are debugging). At the moment,
4501 it prints the address mappings of the process.
4503 If you bring up GDB on another SVR4 system, please send mail to
4504 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4506 * Better dynamic linking support in SunOS
4508 Reading symbols from shared libraries which contain debugging symbols
4509 now works properly. However, there remain issues such as automatic
4510 skipping of `transfer vector' code during function calls, which
4511 make it harder to debug code in a shared library, than to debug the
4512 same code linked statically.
4516 GDB is now using the latest `getopt' routines from the FSF. This
4517 version accepts the -- prefix for options with long names. GDB will
4518 continue to accept the old forms (-option and +option) as well.
4519 Various single letter abbreviations for options have been explicity
4520 added to the option table so that they won't get overshadowed in the
4521 future by other options that begin with the same letter.
4525 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4526 Many assorted bugs have been handled. Many more remain to be handled.
4527 See the various ChangeLog files (primarily in gdb and bfd) for details.
4530 *** Changes in GDB-4.3:
4532 * New machines supported (host and target)
4534 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4535 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4536 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4538 * Almost SCO Unix support
4540 We had hoped to support:
4541 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4542 (except for core file support), but we discovered very late in the release
4543 that it has problems with process groups that render gdb unusable. Sorry
4544 about that. I encourage people to fix it and post the fixes.
4546 * Preliminary ELF and DWARF support
4548 GDB can read ELF object files on System V Release 4, and can handle
4549 debugging records for C, in DWARF format, in ELF files. This support
4550 is preliminary. If you bring up GDB on another SVR4 system, please
4551 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4556 GDB now uses the latest `readline' library. One user-visible change
4557 is that two tabs will list possible command completions, which previously
4558 required typing M-? (meta-question mark, or ESC ?).
4562 The `stepi' bug that many of you noticed has been squashed.
4563 Many bugs in C++ have been handled. Many more remain to be handled.
4564 See the various ChangeLog files (primarily in gdb and bfd) for details.
4566 * State of the MIPS world (in case you wondered):
4568 GDB can understand the symbol tables emitted by the compilers
4569 supplied by most vendors of MIPS-based machines, including DEC. These
4570 symbol tables are in a format that essentially nobody else uses.
4572 Some versions of gcc come with an assembler post-processor called
4573 mips-tfile. This program is required if you want to do source-level
4574 debugging of gcc-compiled programs. I believe FSF does not ship
4575 mips-tfile with gcc version 1, but it will eventually come with gcc
4578 Debugging of g++ output remains a problem. g++ version 1.xx does not
4579 really support it at all. (If you're lucky, you should be able to get
4580 line numbers and stack traces to work, but no parameters or local
4581 variables.) With some work it should be possible to improve the
4584 When gcc version 2 is released, you will have somewhat better luck.
4585 However, even then you will get confusing results for inheritance and
4588 We will eventually provide full debugging of g++ output on
4589 DECstations. This will probably involve some kind of stabs-in-ecoff
4590 encapulation, but the details have not been worked out yet.
4593 *** Changes in GDB-4.2:
4595 * Improved configuration
4597 Only one copy of `configure' exists now, and it is not self-modifying.
4598 Porting BFD is simpler.
4602 The `step' and `next' commands now only stop at the first instruction
4603 of a source line. This prevents the multiple stops that used to occur
4604 in switch statements, for-loops, etc. `Step' continues to stop if a
4605 function that has debugging information is called within the line.
4609 Lots of small bugs fixed. More remain.
4611 * New host supported (not target)
4613 Intel 386 PC clone running Mach i386-none-mach
4616 *** Changes in GDB-4.1:
4618 * Multiple source language support
4620 GDB now has internal scaffolding to handle several source languages.
4621 It determines the type of each source file from its filename extension,
4622 and will switch expression parsing and number formatting to match the
4623 language of the function in the currently selected stack frame.
4624 You can also specifically set the language to be used, with
4625 `set language c' or `set language modula-2'.
4629 GDB now has preliminary support for the GNU Modula-2 compiler,
4630 currently under development at the State University of New York at
4631 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4632 continue through the fall of 1991 and into 1992.
4634 Other Modula-2 compilers are currently not supported, and attempting to
4635 debug programs compiled with them will likely result in an error as the
4636 symbol table is read. Feel free to work on it, though!
4638 There are hooks in GDB for strict type checking and range checking,
4639 in the `Modula-2 philosophy', but they do not currently work.
4643 GDB can now write to executable and core files (e.g. patch
4644 a variable's value). You must turn this switch on, specify
4645 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4646 by assigning a new value to a variable. Modifications take
4649 * Automatic SunOS shared library reading
4651 When you run your program, GDB automatically determines where its
4652 shared libraries (if any) have been loaded, and reads their symbols.
4653 The `share' command is no longer needed. This also works when
4654 examining core files.
4658 You can specify the number of lines that the `list' command shows.
4661 * New machines supported (host and target)
4663 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4664 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4665 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4667 * New hosts supported (not targets)
4669 IBM RT/PC: romp-ibm-aix or rtpc
4671 * New targets supported (not hosts)
4673 AMD 29000 embedded with COFF a29k-none-coff
4674 AMD 29000 embedded with a.out a29k-none-aout
4675 Ultracomputer remote kernel debug a29k-nyu-kern
4677 * New remote interfaces
4683 *** Changes in GDB-4.0:
4687 Wide output is wrapped at good places to make the output more readable.
4689 Gdb now supports cross-debugging from a host machine of one type to a
4690 target machine of another type. Communication with the target system
4691 is over serial lines. The ``target'' command handles connecting to the
4692 remote system; the ``load'' command will download a program into the
4693 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4694 also supports debugging of realtime processes running under VxWorks,
4695 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4696 stub on the target system.
4698 New CPUs supported include the AMD 29000 and Intel 960.
4700 GDB now reads object files and symbol tables via a ``binary file''
4701 library, which allows a single copy of GDB to debug programs of multiple
4702 object file types such as a.out and coff.
4704 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4705 refcard.dvi and refcard.ps are available to format it).
4708 * Control-Variable user interface simplified
4710 All variables that control the operation of the debugger can be set
4711 by the ``set'' command, and displayed by the ``show'' command.
4713 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4714 ``Show prompt'' produces the response:
4715 Gdb's prompt is new-gdb=>.
4717 What follows are the NEW set commands. The command ``help set'' will
4718 print a complete list of old and new set commands. ``help set FOO''
4719 will give a longer description of the variable FOO. ``show'' will show
4720 all of the variable descriptions and their current settings.
4722 confirm on/off: Enables warning questions for operations that are
4723 hard to recover from, e.g. rerunning the program while
4724 it is already running. Default is ON.
4726 editing on/off: Enables EMACS style command line editing
4727 of input. Previous lines can be recalled with
4728 control-P, the current line can be edited with control-B,
4729 you can search for commands with control-R, etc.
4732 history filename NAME: NAME is where the gdb command history
4733 will be stored. The default is .gdb_history,
4734 or the value of the environment variable
4737 history size N: The size, in commands, of the command history. The
4738 default is 256, or the value of the environment variable
4741 history save on/off: If this value is set to ON, the history file will
4742 be saved after exiting gdb. If set to OFF, the
4743 file will not be saved. The default is OFF.
4745 history expansion on/off: If this value is set to ON, then csh-like
4746 history expansion will be performed on
4747 command line input. The default is OFF.
4749 radix N: Sets the default radix for input and output. It can be set
4750 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4751 in the current radix, so "set radix 10" is always a no-op.
4753 height N: This integer value is the number of lines on a page. Default
4754 is 24, the current `stty rows'' setting, or the ``li#''
4755 setting from the termcap entry matching the environment
4758 width N: This integer value is the number of characters on a line.
4759 Default is 80, the current `stty cols'' setting, or the ``co#''
4760 setting from the termcap entry matching the environment
4763 Note: ``set screensize'' is obsolete. Use ``set height'' and
4764 ``set width'' instead.
4766 print address on/off: Print memory addresses in various command displays,
4767 such as stack traces and structure values. Gdb looks
4768 more ``symbolic'' if you turn this off; it looks more
4769 ``machine level'' with it on. Default is ON.
4771 print array on/off: Prettyprint arrays. New convenient format! Default
4774 print demangle on/off: Print C++ symbols in "source" form if on,
4777 print asm-demangle on/off: Same, for assembler level printouts
4780 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4783 * Support for Epoch Environment.
4785 The epoch environment is a version of Emacs v18 with windowing. One
4786 new command, ``inspect'', is identical to ``print'', except that if you
4787 are running in the epoch environment, the value is printed in its own
4791 * Support for Shared Libraries
4793 GDB can now debug programs and core files that use SunOS shared libraries.
4794 Symbols from a shared library cannot be referenced
4795 before the shared library has been linked with the program (this
4796 happens after you type ``run'' and before the function main() is entered).
4797 At any time after this linking (including when examining core files
4798 from dynamically linked programs), gdb reads the symbols from each
4799 shared library when you type the ``sharedlibrary'' command.
4800 It can be abbreviated ``share''.
4802 sharedlibrary REGEXP: Load shared object library symbols for files
4803 matching a unix regular expression. No argument
4804 indicates to load symbols for all shared libraries.
4806 info sharedlibrary: Status of loaded shared libraries.
4811 A watchpoint stops execution of a program whenever the value of an
4812 expression changes. Checking for this slows down execution
4813 tremendously whenever you are in the scope of the expression, but is
4814 quite useful for catching tough ``bit-spreader'' or pointer misuse
4815 problems. Some machines such as the 386 have hardware for doing this
4816 more quickly, and future versions of gdb will use this hardware.
4818 watch EXP: Set a watchpoint (breakpoint) for an expression.
4820 info watchpoints: Information about your watchpoints.
4822 delete N: Deletes watchpoint number N (same as breakpoints).
4823 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4824 enable N: Re-enables watchpoint number N (same as breakpoints).
4827 * C++ multiple inheritance
4829 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4832 * C++ exception handling
4834 Gdb now supports limited C++ exception handling. Besides the existing
4835 ability to breakpoint on an exception handler, gdb can breakpoint on
4836 the raising of an exception (before the stack is peeled back to the
4839 catch FOO: If there is a FOO exception handler in the dynamic scope,
4840 set a breakpoint to catch exceptions which may be raised there.
4841 Multiple exceptions (``catch foo bar baz'') may be caught.
4843 info catch: Lists all exceptions which may be caught in the
4844 current stack frame.
4847 * Minor command changes
4849 The command ``call func (arg, arg, ...)'' now acts like the print
4850 command, except it does not print or save a value if the function's result
4851 is void. This is similar to dbx usage.
4853 The ``up'' and ``down'' commands now always print the frame they end up
4854 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4855 frames without printing.
4857 * New directory command
4859 'dir' now adds directories to the FRONT of the source search path.
4860 The path starts off empty. Source files that contain debug information
4861 about the directory in which they were compiled can be found even
4862 with an empty path; Sun CC and GCC include this information. If GDB can't
4863 find your source file in the current directory, type "dir .".
4865 * Configuring GDB for compilation
4867 For normal use, type ``./configure host''. See README or gdb.texinfo
4870 GDB now handles cross debugging. If you are remotely debugging between
4871 two different machines, type ``./configure host -target=targ''.
4872 Host is the machine where GDB will run; targ is the machine
4873 where the program that you are debugging will run.