1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.4
6 * GDB now supports reversible debugging on ARM, it allows you to
7 debug basic ARM and THUMB instructions, and provides
10 * The option "symbol-reloading" has been deleted as it is no longer used.
14 ** GDB commands implemented in Python can now be put in command class
17 ** The "maint set python print-stack on|off" is now deleted.
19 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
20 apply "flag enum"-style pretty-printing to any enum.
22 ** gdb.lookup_symbol can now work when there is no current frame.
24 ** gdb.Symbol now has a 'line' attribute, holding the line number in
25 the source at which the symbol was defined.
27 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
28 method 'value'. The former indicates whether the symbol needs a
29 frame in order to compute its value, and the latter computes the
32 ** A new method 'referenced_value' on gdb.Value objects which can
33 dereference pointer as well as C++ reference values.
35 * GDBserver now supports stdio connections.
36 E.g. (gdb) target remote | ssh myhost gdbserver - hello
38 * The binary "gdbtui" can no longer be built or installed.
39 Use "gdb -tui" instead.
41 * GDB will now print "flag" enums specially. A flag enum is one where
42 all the enumerator values have no bits in common when pairwise
43 "and"ed. When printing a value whose type is a flag enum, GDB will
44 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
45 (gdb) print (enum E) 3
48 * The filename part of a linespec will now match trailing components
49 of a source file name. For example, "break gcc/expr.c:1000" will
50 now set a breakpoint in build/gcc/expr.c, but not
53 * The "info proc" and "generate-core-file" commands will now also
54 work on remote targets connected to GDBserver on Linux.
56 * The command "info catch" has been removed. It has been disabled
59 * The "catch exception" and "catch assert" commands now accept
60 a condition at the end of the command, much like the "break"
61 command does. For instance:
63 (gdb) catch exception Constraint_Error if Barrier = True
65 Previously, it was possible to add a condition to such catchpoints,
66 but it had to be done as a second step, after the catchpoint had been
67 created, using the "condition" command.
69 * The "info static-tracepoint-marker" command will now also work on
70 native Linux targets with in-process agent.
72 * GDB can now set breakpoints on inlined functions.
74 * The .gdb_index section has been updated to include symbols for
75 inlined functions. GDB will ignore older .gdb_index sections by
76 default, which could cause symbol files to be loaded more slowly
77 until their .gdb_index sections can be recreated. The new option
78 --use-deprecated-index-sections will cause GDB to use any older
79 .gdb_index sections it finds. This will restore performance, but
80 the ability to set breakpoints on inlined functions will be lost
81 in symbol files with older .gdb_index sections.
83 * Ada support for GDB/MI Variable Objects has been added.
87 ** "catch load" and "catch unload" can be used to stop when a shared
88 library is loaded or unloaded, respectively.
90 ** "enable count" can be used to auto-disable a breakpoint after
93 ** "info vtbl" can be used to show the virtual method tables for
96 ** "explore" and its sub commands "explore value" and "explore type"
97 can be used to reccursively explore values and types of
98 expressions. These commands are available only if GDB is
99 configured with '--with-python'.
103 Renesas RL78 rl78-*-elf
104 HP OpenVMS ia64 ia64-hp-openvms*
106 * GDBserver supports evaluation of breakpoint conditions. When
107 support is advertised by GDBserver, GDB may be told to send the
108 breakpoint conditions in bytecode form to GDBserver. GDBserver
109 will only report the breakpoint trigger to GDB when its condition
114 set breakpoint condition-evaluation
115 show breakpoint condition-evaluation
116 Control whether breakpoint conditions are evaluated by GDB ("host") or by
117 GDBserver ("target"). Default option "auto" chooses the most efficient
119 This option can improve debugger efficiency depending on the speed of the
124 z0/z1 conditional breakpoints extension
126 The z0/z1 breakpoint insertion packets have been extended to carry
127 a list of conditional expressions over to the remote stub depending on the
128 condition evaluation mode. The use of this extension can be controlled
129 via the "set remote conditional-breakpoints-packet" command.
133 Specify the signals which the remote stub may pass to the debugged
134 program without GDB involvement.
136 * New command line options
138 --init-command=FILE, -ix Like --command, -x but execute it
139 before loading inferior.
140 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
141 execute it before loading inferior.
143 *** Changes in GDB 7.4
145 * GDB now handles ambiguous linespecs more consistently; the existing
146 FILE:LINE support has been expanded to other types of linespecs. A
147 breakpoint will now be set on all matching locations in all
148 inferiors, and locations will be added or removed according to
151 * GDB now allows you to skip uninteresting functions and files when
152 stepping with the "skip function" and "skip file" commands.
154 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
155 and "show remote hardware-watchpoint-length-limit". These allows to
156 set or show the maximum length limit (in bytes) of a remote
157 target hardware watchpoint.
159 This allows e.g. to use "unlimited" hardware watchpoints with the
160 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
161 watchpoints are slower than real hardware watchpoints but are
162 significantly faster than gdb software watchpoints.
166 ** The register_pretty_printer function in module gdb.printing now takes
167 an optional `replace' argument. If True, the new printer replaces any
170 ** The "maint set python print-stack on|off" command has been
171 deprecated and will be deleted in GDB 7.5.
172 A new command: "set python print-stack none|full|message" has
173 replaced it. Additionally, the default for "print-stack" is
174 now "message", which just prints the error message without
177 ** A prompt substitution hook (prompt_hook) is now available to the
180 ** A new Python module, gdb.prompt has been added to the GDB Python
181 modules library. This module provides functionality for
182 escape sequences in prompts (used by set/show
183 extended-prompt). These escape sequences are replaced by their
186 ** Python commands and convenience-functions located in
187 'data-directory'/python/gdb/command and
188 'data-directory'/python/gdb/function are now automatically loaded
191 ** Blocks now provide four new attributes. global_block and
192 static_block will return the global and static blocks
193 respectively. is_static and is_global are boolean attributes
194 that indicate if the block is one of those two types.
196 ** Symbols now provide the "type" attribute, the type of the symbol.
198 ** The "gdb.breakpoint" function has been deprecated in favor of
201 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
202 of a function. This class is based on the "finish" command
203 available in the CLI.
205 ** Type objects for struct and union types now allow access to
206 the fields using standard Python dictionary (mapping) methods.
207 For example, "some_type['myfield']" now works, as does
210 ** A new event "gdb.new_objfile" has been added, triggered by loading a
213 ** A new function, "deep_items" has been added to the gdb.types
214 module in the GDB Python modules library. This function returns
215 an iterator over the fields of a struct or union type. Unlike
216 the standard Python "iteritems" method, it will recursively traverse
217 any anonymous fields.
221 ** "*stopped" events can report several new "reason"s, such as
224 ** Breakpoint changes are now notified using new async records, like
225 "=breakpoint-modified".
227 ** New command -ada-task-info.
229 * libthread-db-search-path now supports two special values: $sdir and $pdir.
230 $sdir specifies the default system locations of shared libraries.
231 $pdir specifies the directory where the libpthread used by the application
234 GDB no longer looks in $sdir and $pdir after it has searched the directories
235 mentioned in libthread-db-search-path. If you want to search those
236 directories, they must be specified in libthread-db-search-path.
237 The default value of libthread-db-search-path on GNU/Linux and Solaris
238 systems is now "$sdir:$pdir".
240 $pdir is not supported by gdbserver, it is currently ignored.
241 $sdir is supported by gdbserver.
243 * New configure option --with-iconv-bin.
244 When using the internationalization support like the one in the GNU C
245 library, GDB will invoke the "iconv" program to get a list of supported
246 character sets. If this program lives in a non-standard location, one can
247 use this option to specify where to find it.
249 * When natively debugging programs on PowerPC BookE processors running
250 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
251 watchpoints, which specify a mask in addition to an address to watch.
252 The mask specifies that some bits of an address (the bits which are
253 reset in the mask) should be ignored when matching the address accessed
254 by the inferior against the watchpoint address. See the "PowerPC Embedded"
255 section in the user manual for more details.
257 * The new option --once causes GDBserver to stop listening for connections once
258 the first connection is made. The listening port used by GDBserver will
259 become available after that.
261 * New commands "info macros" and "alias" have been added.
263 * New function parameters suffix @entry specifies value of function parameter
264 at the time the function got called. Entry values are available only since
270 "!" is now an alias of the "shell" command.
271 Note that no space is needed between "!" and SHELL COMMAND.
275 watch EXPRESSION mask MASK_VALUE
276 The watch command now supports the mask argument which allows creation
277 of masked watchpoints, if the current architecture supports this feature.
279 info auto-load-scripts [REGEXP]
280 This command was formerly named "maintenance print section-scripts".
281 It is now generally useful and is no longer a maintenance-only command.
283 info macro [-all] [--] MACRO
284 The info macro command has new options `-all' and `--'. The first for
285 printing all definitions of a macro. The second for explicitly specifying
286 the end of arguments and the beginning of the macro name in case the macro
287 name starts with a hyphen.
289 collect[/s] EXPRESSIONS
290 The tracepoint collect command now takes an optional modifier "/s"
291 that directs it to dereference pointer-to-character types and
292 collect the bytes of memory up to a zero byte. The behavior is
293 similar to what you see when you use the regular print command on a
294 string. An optional integer following the "/s" sets a bound on the
295 number of bytes that will be collected.
298 The trace start command now interprets any supplied arguments as a
299 note to be recorded with the trace run, with an effect similar to
300 setting the variable trace-notes.
303 The trace stop command now interprets any arguments as a note to be
304 mentioned along with the tstatus report that the trace was stopped
305 with a command. The effect is similar to setting the variable
308 * Tracepoints can now be enabled and disabled at any time after a trace
309 experiment has been started using the standard "enable" and "disable"
310 commands. It is now possible to start a trace experiment with no enabled
311 tracepoints; GDB will display a warning, but will allow the experiment to
312 begin, assuming that tracepoints will be enabled as needed while the trace
315 * Fast tracepoints on 32-bit x86-architectures can now be placed at
316 locations with 4-byte instructions, when they were previously
317 limited to locations with instructions of 5 bytes or longer.
323 Set the GDB prompt, and allow escape sequences to be inserted to
324 display miscellaneous information (see 'help set extended-prompt'
325 for the list of sequences). This prompt (and any information
326 accessed through the escape sequences) is updated every time the
329 set print entry-values (both|compact|default|if-needed|no|only|preferred)
330 show print entry-values
331 Set printing of frame argument values at function entry. In some cases
332 GDB can determine the value of function argument which was passed by the
333 function caller, even if the value was modified inside the called function.
335 set debug entry-values
336 show debug entry-values
337 Control display of debugging info for determining frame argument values at
338 function entry and virtual tail call frames.
340 set basenames-may-differ
341 show basenames-may-differ
342 Set whether a source file may have multiple base names.
343 (A "base name" is the name of a file with the directory part removed.
344 Example: The base name of "/home/user/hello.c" is "hello.c".)
345 If set, GDB will canonicalize file names (e.g., expand symlinks)
346 before comparing them. Canonicalization is an expensive operation,
347 but it allows the same file be known by more than one base name.
348 If not set (the default), all source files are assumed to have just
349 one base name, and gdb will do file name comparisons more efficiently.
355 Set a user name and notes for the current and any future trace runs.
356 This is useful for long-running and/or disconnected traces, to
357 inform others (or yourself) as to who is running the trace, supply
358 contact information, or otherwise explain what is going on.
361 show trace-stop-notes
362 Set a note attached to the trace run, that is displayed when the
363 trace has been stopped by a tstop command. This is useful for
364 instance as an explanation, if you are stopping a trace run that was
365 started by someone else.
371 Dynamically enable a tracepoint in a started trace experiment.
375 Dynamically disable a tracepoint in a started trace experiment.
379 Set the user and notes of the trace run.
383 Query the current status of a tracepoint.
387 Query the minimum length of instruction at which a fast tracepoint may
390 * Dcache size (number of lines) and line-size are now runtime-configurable
391 via "set dcache line" and "set dcache line-size" commands.
395 Texas Instruments TMS320C6x tic6x-*-*
399 Renesas RL78 rl78-*-elf
401 *** Changes in GDB 7.3.1
403 * The build failure for NetBSD and OpenBSD targets have now been fixed.
405 *** Changes in GDB 7.3
407 * GDB has a new command: "thread find [REGEXP]".
408 It finds the thread id whose name, target id, or thread extra info
409 matches the given regular expression.
411 * The "catch syscall" command now works on mips*-linux* targets.
413 * The -data-disassemble MI command now supports modes 2 and 3 for
414 dumping the instruction opcodes.
416 * New command line options
418 -data-directory DIR Specify DIR as the "data-directory".
419 This is mostly for testing purposes.
421 * The "maint set python auto-load on|off" command has been renamed to
422 "set auto-load-scripts on|off".
424 * GDB has a new command: "set directories".
425 It is like the "dir" command except that it replaces the
426 source path list instead of augmenting it.
428 * GDB now understands thread names.
430 On GNU/Linux, "info threads" will display the thread name as set by
431 prctl or pthread_setname_np.
433 There is also a new command, "thread name", which can be used to
434 assign a name internally for GDB to display.
437 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
438 has been integrated into GDB.
442 ** The function gdb.Write now accepts an optional keyword 'stream'.
443 This keyword, when provided, will direct the output to either
444 stdout, stderr, or GDB's logging output.
446 ** Parameters can now be be sub-classed in Python, and in particular
447 you may implement the get_set_doc and get_show_doc functions.
448 This improves how Parameter set/show documentation is processed
449 and allows for more dynamic content.
451 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
452 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
453 have an is_valid method.
455 ** Breakpoints can now be sub-classed in Python, and in particular
456 you may implement a 'stop' function that is executed each time
457 the inferior reaches that breakpoint.
459 ** New function gdb.lookup_global_symbol looks up a global symbol.
461 ** GDB values in Python are now callable if the value represents a
462 function. For example, if 'some_value' represents a function that
463 takes two integer parameters and returns a value, you can call
464 that function like so:
466 result = some_value (10,20)
468 ** Module gdb.types has been added.
469 It contains a collection of utilities for working with gdb.Types objects:
470 get_basic_type, has_field, make_enum_dict.
472 ** Module gdb.printing has been added.
473 It contains utilities for writing and registering pretty-printers.
474 New classes: PrettyPrinter, SubPrettyPrinter,
475 RegexpCollectionPrettyPrinter.
476 New function: register_pretty_printer.
478 ** New commands "info pretty-printers", "enable pretty-printer" and
479 "disable pretty-printer" have been added.
481 ** gdb.parameter("directories") is now available.
483 ** New function gdb.newest_frame returns the newest frame in the
486 ** The gdb.InferiorThread class has a new "name" attribute. This
487 holds the thread's name.
489 ** Python Support for Inferior events.
490 Python scripts can add observers to be notified of events
491 occurring in the process being debugged.
492 The following events are currently supported:
493 - gdb.events.cont Continue event.
494 - gdb.events.exited Inferior exited event.
495 - gdb.events.stop Signal received, and Breakpoint hit events.
499 ** GDB now puts template parameters in scope when debugging in an
500 instantiation. For example, if you have:
502 template<int X> int func (void) { return X; }
504 then if you step into func<5>, "print X" will show "5". This
505 feature requires proper debuginfo support from the compiler; it
506 was added to GCC 4.5.
508 ** The motion commands "next", "finish", "until", and "advance" now
509 work better when exceptions are thrown. In particular, GDB will
510 no longer lose control of the inferior; instead, the GDB will
511 stop the inferior at the point at which the exception is caught.
512 This functionality requires a change in the exception handling
513 code that was introduced in GCC 4.5.
515 * GDB now follows GCC's rules on accessing volatile objects when
516 reading or writing target state during expression evaluation.
517 One notable difference to prior behavior is that "print x = 0"
518 no longer generates a read of x; the value of the assignment is
519 now always taken directly from the value being assigned.
521 * GDB now has some support for using labels in the program's source in
522 linespecs. For instance, you can use "advance label" to continue
523 execution to a label.
525 * GDB now has support for reading and writing a new .gdb_index
526 section. This section holds a fast index of DWARF debugging
527 information and can be used to greatly speed up GDB startup and
528 operation. See the documentation for `save gdb-index' for details.
530 * The "watch" command now accepts an optional "-location" argument.
531 When used, this causes GDB to watch the memory referred to by the
532 expression. Such a watchpoint is never deleted due to it going out
535 * GDB now supports thread debugging of core dumps on GNU/Linux.
537 GDB now activates thread debugging using the libthread_db library
538 when debugging GNU/Linux core dumps, similarly to when debugging
539 live processes. As a result, when debugging a core dump file, GDB
540 is now able to display pthread_t ids of threads. For example, "info
541 threads" shows the same output as when debugging the process when it
542 was live. In earlier releases, you'd see something like this:
545 * 1 LWP 6780 main () at main.c:10
547 While now you see this:
550 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
552 It is also now possible to inspect TLS variables when debugging core
555 When debugging a core dump generated on a machine other than the one
556 used to run GDB, you may need to point GDB at the correct
557 libthread_db library with the "set libthread-db-search-path"
558 command. See the user manual for more details on this command.
560 * When natively debugging programs on PowerPC BookE processors running
561 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
562 which stop execution of the inferior whenever it executes an instruction
563 at any address within the specified range. See the "PowerPC Embedded"
564 section in the user manual for more details.
566 * New features in the GDB remote stub, GDBserver
568 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
569 and i686 LynxOS (version 5.x).
571 ** GDBserver is now supported on Blackfin Linux.
573 * New native configurations
575 ia64 HP-UX ia64-*-hpux*
579 Analog Devices, Inc. Blackfin Processor bfin-*
581 * Ada task switching is now supported on sparc-elf targets when
582 debugging a program using the Ravenscar Profile. For more information,
583 see the "Tasking Support when using the Ravenscar Profile" section
584 in the GDB user manual.
586 * Guile support was removed.
588 * New features in the GNU simulator
590 ** The --map-info flag lists all known core mappings.
592 ** CFI flashes may be simulated via the "cfi" device.
594 *** Changes in GDB 7.2
596 * Shared library support for remote targets by default
598 When GDB is configured for a generic, non-OS specific target, like
599 for example, --target=arm-eabi or one of the many *-*-elf targets,
600 GDB now queries remote stubs for loaded shared libraries using the
601 `qXfer:libraries:read' packet. Previously, shared library support
602 was always disabled for such configurations.
606 ** Argument Dependent Lookup (ADL)
608 In C++ ADL lookup directs function search to the namespaces of its
609 arguments even if the namespace has not been imported.
619 Here the compiler will search for `foo' in the namespace of 'b'
620 and find A::foo. GDB now supports this. This construct is commonly
621 used in the Standard Template Library for operators.
623 ** Improved User Defined Operator Support
625 In addition to member operators, GDB now supports lookup of operators
626 defined in a namespace and imported with a `using' directive, operators
627 defined in the global scope, operators imported implicitly from an
628 anonymous namespace, and the ADL operators mentioned in the previous
630 GDB now also supports proper overload resolution for all the previously
631 mentioned flavors of operators.
633 ** static const class members
635 Printing of static const class members that are initialized in the
636 class definition has been fixed.
638 * Windows Thread Information Block access.
640 On Windows targets, GDB now supports displaying the Windows Thread
641 Information Block (TIB) structure. This structure is visible either
642 by using the new command `info w32 thread-information-block' or, by
643 dereferencing the new convenience variable named `$_tlb', a
644 thread-specific pointer to the TIB. This feature is also supported
645 when remote debugging using GDBserver.
649 Static tracepoints are calls in the user program into a tracing
650 library. One such library is a port of the LTTng kernel tracer to
651 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
652 When debugging with GDBserver, GDB now supports combining the GDB
653 tracepoint machinery with such libraries. For example: the user can
654 use GDB to probe a static tracepoint marker (a call from the user
655 program into the tracing library) with the new "strace" command (see
656 "New commands" below). This creates a "static tracepoint" in the
657 breakpoint list, that can be manipulated with the same feature set
658 as fast and regular tracepoints. E.g., collect registers, local and
659 global variables, collect trace state variables, and define
660 tracepoint conditions. In addition, the user can collect extra
661 static tracepoint marker specific data, by collecting the new
662 $_sdata internal variable. When analyzing the trace buffer, you can
663 inspect $_sdata like any other variable available to GDB. For more
664 information, see the "Tracepoints" chapter in GDB user manual. New
665 remote packets have been defined to support static tracepoints, see
666 the "New remote packets" section below.
668 * Better reconstruction of tracepoints after disconnected tracing
670 GDB will attempt to download the original source form of tracepoint
671 definitions when starting a trace run, and then will upload these
672 upon reconnection to the target, resulting in a more accurate
673 reconstruction of the tracepoints that are in use on the target.
677 You can now exercise direct control over the ways that GDB can
678 affect your program. For instance, you can disallow the setting of
679 breakpoints, so that the program can run continuously (assuming
680 non-stop mode). In addition, the "observer" variable is available
681 to switch all of the different controls; in observer mode, GDB
682 cannot affect the target's behavior at all, which is useful for
683 tasks like diagnosing live systems in the field.
685 * The new convenience variable $_thread holds the number of the
692 Return the address of the Windows Thread Information Block of a given thread.
696 In response to several of the tracepoint packets, the target may now
697 also respond with a number of intermediate `qRelocInsn' request
698 packets before the final result packet, to have GDB handle
699 relocating an instruction to execute at a different address. This
700 is particularly useful for stubs that support fast tracepoints. GDB
701 reports support for this feature in the qSupported packet.
705 List static tracepoint markers in the target program.
709 List static tracepoint markers at a given address in the target
712 qXfer:statictrace:read
714 Read the static trace data collected (by a `collect $_sdata'
715 tracepoint action). The remote stub reports support for this packet
716 to gdb's qSupported query.
720 Send the current settings of GDB's permission flags.
724 Send part of the source (textual) form of a tracepoint definition,
725 which includes location, conditional, and action list.
727 * The source command now accepts a -s option to force searching for the
728 script in the source search path even if the script name specifies
731 * New features in the GDB remote stub, GDBserver
733 - GDBserver now support tracepoints (including fast tracepoints, and
734 static tracepoints). The feature is currently supported by the
735 i386-linux and amd64-linux builds. See the "Tracepoints support
736 in gdbserver" section in the manual for more information.
738 GDBserver JIT compiles the tracepoint's conditional agent
739 expression bytecode into native code whenever possible for low
740 overhead dynamic tracepoints conditionals. For such tracepoints,
741 an expression that examines program state is evaluated when the
742 tracepoint is reached, in order to determine whether to capture
743 trace data. If the condition is simple and false, processing the
744 tracepoint finishes very quickly and no data is gathered.
746 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
747 for static tracepoints support.
749 - GDBserver now supports x86_64 Windows 64-bit debugging.
751 * GDB now sends xmlRegisters= in qSupported packet to indicate that
752 it understands register description.
754 * The --batch flag now disables pagination and queries.
756 * X86 general purpose registers
758 GDB now supports reading/writing byte, word and double-word x86
759 general purpose registers directly. This means you can use, say,
760 $ah or $ax to refer, respectively, to the byte register AH and
761 16-bit word register AX that are actually portions of the 32-bit
762 register EAX or 64-bit register RAX.
764 * The `commands' command now accepts a range of breakpoints to modify.
765 A plain `commands' following a command that creates multiple
766 breakpoints affects all the breakpoints set by that command. This
767 applies to breakpoints set by `rbreak', and also applies when a
768 single `break' command creates multiple breakpoints (e.g.,
769 breakpoints on overloaded c++ functions).
771 * The `rbreak' command now accepts a filename specification as part of
772 its argument, limiting the functions selected by the regex to those
773 in the specified file.
775 * Support for remote debugging Windows and SymbianOS shared libraries
776 from Unix hosts has been improved. Non Windows GDB builds now can
777 understand target reported file names that follow MS-DOS based file
778 system semantics, such as file names that include drive letters and
779 use the backslash character as directory separator. This makes it
780 possible to transparently use the "set sysroot" and "set
781 solib-search-path" on Unix hosts to point as host copies of the
782 target's shared libraries. See the new command "set
783 target-file-system-kind" described below, and the "Commands to
784 specify files" section in the user manual for more information.
788 eval template, expressions...
789 Convert the values of one or more expressions under the control
790 of the string template to a command line, and call it.
792 set target-file-system-kind unix|dos-based|auto
793 show target-file-system-kind
794 Set or show the assumed file system kind for target reported file
797 save breakpoints <filename>
798 Save all current breakpoint definitions to a file suitable for use
799 in a later debugging session. To read the saved breakpoint
800 definitions, use the `source' command.
802 `save tracepoints' is a new alias for `save-tracepoints'. The latter
805 info static-tracepoint-markers
806 Display information about static tracepoint markers in the target.
808 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
809 Define a static tracepoint by probing a marker at the given
810 function, line, address, or marker ID.
814 Enable and disable observer mode.
816 set may-write-registers on|off
817 set may-write-memory on|off
818 set may-insert-breakpoints on|off
819 set may-insert-tracepoints on|off
820 set may-insert-fast-tracepoints on|off
821 set may-interrupt on|off
822 Set individual permissions for GDB effects on the target. Note that
823 some of these settings can have undesirable or surprising
824 consequences, particularly when changed in the middle of a session.
825 For instance, disabling the writing of memory can prevent
826 breakpoints from being inserted, cause single-stepping to fail, or
827 even crash your program, if you disable after breakpoints have been
828 inserted. However, GDB should not crash.
830 set record memory-query on|off
831 show record memory-query
832 Control whether to stop the inferior if memory changes caused
833 by an instruction cannot be recorded.
838 The disassemble command now supports "start,+length" form of two arguments.
842 ** GDB now provides a new directory location, called the python directory,
843 where Python scripts written for GDB can be installed. The location
844 of that directory is <data-directory>/python, where <data-directory>
845 is the GDB data directory. For more details, see section `Scripting
846 GDB using Python' in the manual.
848 ** The GDB Python API now has access to breakpoints, symbols, symbol
849 tables, program spaces, inferiors, threads and frame's code blocks.
850 Additionally, GDB Parameters can now be created from the API, and
851 manipulated via set/show in the CLI.
853 ** New functions gdb.target_charset, gdb.target_wide_charset,
854 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
856 ** New exception gdb.GdbError.
858 ** Pretty-printers are now also looked up in the current program space.
860 ** Pretty-printers can now be individually enabled and disabled.
862 ** GDB now looks for names of Python scripts to auto-load in a
863 special section named `.debug_gdb_scripts', in addition to looking
864 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
866 * Tracepoint actions were unified with breakpoint commands. In particular,
867 there are no longer differences in "info break" output for breakpoints and
868 tracepoints and the "commands" command can be used for both tracepoints and
873 ARM Symbian arm*-*-symbianelf*
875 * D language support.
876 GDB now supports debugging programs written in the D programming
879 * GDB now supports the extended ptrace interface for PowerPC which is
880 available since Linux kernel version 2.6.34. This automatically enables
881 any hardware breakpoints and additional hardware watchpoints available in
882 the processor. The old ptrace interface exposes just one hardware
883 watchpoint and no hardware breakpoints.
885 * GDB is now able to use the Data Value Compare (DVC) register available on
886 embedded PowerPC processors to implement in hardware simple watchpoint
887 conditions of the form:
889 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
891 This works in native GDB running on Linux kernels with the extended ptrace
892 interface mentioned above.
894 *** Changes in GDB 7.1
900 GDB now supports importing of namespaces in C++. This enables the
901 user to inspect variables from imported namespaces. Support for
902 namepace aliasing has also been added. So, if a namespace is
903 aliased in the current scope (e.g. namepace C=A; ) the user can
904 print variables using the alias (e.g. (gdb) print C::x).
908 All known bugs relating to the printing of virtual base class were
909 fixed. It is now possible to call overloaded static methods using a
914 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
915 and reinterpret_cast<> are now handled by the C++ expression parser.
919 Xilinx MicroBlaze microblaze-*-*
924 Xilinx MicroBlaze microblaze
927 * Multi-program debugging.
929 GDB now has support for multi-program (a.k.a. multi-executable or
930 multi-exec) debugging. This allows for debugging multiple inferiors
931 simultaneously each running a different program under the same GDB
932 session. See "Debugging Multiple Inferiors and Programs" in the
933 manual for more information. This implied some user visible changes
934 in the multi-inferior support. For example, "info inferiors" now
935 lists inferiors that are not running yet or that have exited
936 already. See also "New commands" and "New options" below.
938 * New tracing features
940 GDB's tracepoint facility now includes several new features:
942 ** Trace state variables
944 GDB tracepoints now include support for trace state variables, which
945 are variables managed by the target agent during a tracing
946 experiment. They are useful for tracepoints that trigger each
947 other, so for instance one tracepoint can count hits in a variable,
948 and then a second tracepoint has a condition that is true when the
949 count reaches a particular value. Trace state variables share the
950 $-syntax of GDB convenience variables, and can appear in both
951 tracepoint actions and condition expressions. Use the "tvariable"
952 command to create, and "info tvariables" to view; see "Trace State
953 Variables" in the manual for more detail.
957 GDB now includes an option for defining fast tracepoints, which
958 targets may implement more efficiently, such as by installing a jump
959 into the target agent rather than a trap instruction. The resulting
960 speedup can be by two orders of magnitude or more, although the
961 tradeoff is that some program locations on some target architectures
962 might not allow fast tracepoint installation, for instance if the
963 instruction to be replaced is shorter than the jump. To request a
964 fast tracepoint, use the "ftrace" command, with syntax identical to
965 the regular trace command.
967 ** Disconnected tracing
969 It is now possible to detach GDB from the target while it is running
970 a trace experiment, then reconnect later to see how the experiment
971 is going. In addition, a new variable disconnected-tracing lets you
972 tell the target agent whether to continue running a trace if the
973 connection is lost unexpectedly.
977 GDB now has the ability to save the trace buffer into a file, and
978 then use that file as a target, similarly to you can do with
979 corefiles. You can select trace frames, print data that was
980 collected in them, and use tstatus to display the state of the
981 tracing run at the moment that it was saved. To create a trace
982 file, use "tsave <filename>", and to use it, do "target tfile
985 ** Circular trace buffer
987 You can ask the target agent to handle the trace buffer as a
988 circular buffer, discarding the oldest trace frames to make room for
989 newer ones, by setting circular-trace-buffer to on. This feature may
990 not be available for all target agents.
995 The disassemble command, when invoked with two arguments, now requires
996 the arguments to be comma-separated.
999 The info variables command now displays variable definitions. Files
1000 which only declare a variable are not shown.
1003 The source command is now capable of sourcing Python scripts.
1004 This feature is dependent on the debugger being build with Python
1007 Related to this enhancement is also the introduction of a new command
1008 "set script-extension" (see below).
1010 * New commands (for set/show, see "New options" below)
1012 record save [<FILENAME>]
1013 Save a file (in core file format) containing the process record
1014 execution log for replay debugging at a later time.
1016 record restore <FILENAME>
1017 Restore the process record execution log that was saved at an
1018 earlier time, for replay debugging.
1020 add-inferior [-copies <N>] [-exec <FILENAME>]
1023 clone-inferior [-copies <N>] [ID]
1024 Make a new inferior ready to execute the same program another
1025 inferior has loaded.
1030 maint info program-spaces
1031 List the program spaces loaded into GDB.
1033 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1034 show remote interrupt-sequence
1035 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1036 as the sequence to the remote target in order to interrupt the execution.
1037 Ctrl-C is a default. Some system prefers BREAK which is high level of
1038 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1039 Magic SysRq g. It is BREAK signal and character 'g'.
1041 set remote interrupt-on-connect [on | off]
1042 show remote interrupt-on-connect
1043 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1044 remote target when gdb connects to it. This is needed when you debug
1047 set remotebreak [on | off]
1049 Deprecated. Use "set/show remote interrupt-sequence" instead.
1051 tvariable $NAME [ = EXP ]
1052 Create or modify a trace state variable.
1055 List trace state variables and their values.
1057 delete tvariable $NAME ...
1058 Delete one or more trace state variables.
1061 Evaluate the given expressions without collecting anything into the
1062 trace buffer. (Valid in tracepoint actions only.)
1064 ftrace FN / FILE:LINE / *ADDR
1065 Define a fast tracepoint at the given function, line, or address.
1067 * New expression syntax
1069 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1070 GDB now parses 0b101010 identically with 42.
1074 set follow-exec-mode new|same
1075 show follow-exec-mode
1076 Control whether GDB reuses the same inferior across an exec call or
1077 creates a new one. This is useful to be able to restart the old
1078 executable after the inferior having done an exec call.
1080 set default-collect EXPR, ...
1081 show default-collect
1082 Define a list of expressions to be collected at each tracepoint.
1083 This is a useful way to ensure essential items are not overlooked,
1084 such as registers or a critical global variable.
1086 set disconnected-tracing
1087 show disconnected-tracing
1088 If set to 1, the target is instructed to continue tracing if it
1089 loses its connection to GDB. If 0, the target is to stop tracing
1092 set circular-trace-buffer
1093 show circular-trace-buffer
1094 If set to on, the target is instructed to use a circular trace buffer
1095 and discard the oldest trace frames instead of stopping the trace due
1096 to a full trace buffer. If set to off, the trace stops when the buffer
1097 fills up. Some targets may not support this.
1099 set script-extension off|soft|strict
1100 show script-extension
1101 If set to "off", the debugger does not perform any script language
1102 recognition, and all sourced files are assumed to be GDB scripts.
1103 If set to "soft" (the default), files are sourced according to
1104 filename extension, falling back to GDB scripts if the first
1106 If set to "strict", files are sourced according to filename extension.
1108 set ada trust-PAD-over-XVS on|off
1109 show ada trust-PAD-over-XVS
1110 If off, activate a workaround against a bug in the debugging information
1111 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1112 the GCC sources for more information about the GNAT encoding and
1113 PAD types in particular). It is always safe to set this option to
1114 off, but this introduces a slight performance penalty. The default
1117 * Python API Improvements
1119 ** GDB provides the new class gdb.LazyString. This is useful in
1120 some pretty-printing cases. The new method gdb.Value.lazy_string
1121 provides a simple way to create objects of this type.
1123 ** The fields returned by gdb.Type.fields now have an
1124 `is_base_class' attribute.
1126 ** The new method gdb.Type.range returns the range of an array type.
1128 ** The new method gdb.parse_and_eval can be used to parse and
1129 evaluate an expression.
1131 * New remote packets
1134 Define a trace state variable.
1137 Get the current value of a trace state variable.
1140 Set desired tracing behavior upon disconnection.
1143 Set the trace buffer to be linear or circular.
1146 Get data about the tracepoints currently in use.
1150 Process record now works correctly with hardware watchpoints.
1152 Multiple bug fixes have been made to the mips-irix port, making it
1153 much more reliable. In particular:
1154 - Debugging threaded applications is now possible again. Previously,
1155 GDB would hang while starting the program, or while waiting for
1156 the program to stop at a breakpoint.
1157 - Attaching to a running process no longer hangs.
1158 - An error occurring while loading a core file has been fixed.
1159 - Changing the value of the PC register now works again. This fixes
1160 problems observed when using the "jump" command, or when calling
1161 a function from GDB, or even when assigning a new value to $pc.
1162 - With the "finish" and "return" commands, the return value for functions
1163 returning a small array is now correctly printed.
1164 - It is now possible to break on shared library code which gets executed
1165 during a shared library init phase (code executed while executing
1166 their .init section). Previously, the breakpoint would have no effect.
1167 - GDB is now able to backtrace through the signal handler for
1168 non-threaded programs.
1170 PIE (Position Independent Executable) programs debugging is now supported.
1171 This includes debugging execution of PIC (Position Independent Code) shared
1172 libraries although for that, it should be possible to run such libraries as an
1175 *** Changes in GDB 7.0
1177 * GDB now has an interface for JIT compilation. Applications that
1178 dynamically generate code can create symbol files in memory and register
1179 them with GDB. For users, the feature should work transparently, and
1180 for JIT developers, the interface is documented in the GDB manual in the
1181 "JIT Compilation Interface" chapter.
1183 * Tracepoints may now be conditional. The syntax is as for
1184 breakpoints; either an "if" clause appended to the "trace" command,
1185 or the "condition" command is available. GDB sends the condition to
1186 the target for evaluation using the same bytecode format as is used
1187 for tracepoint actions.
1189 * The disassemble command now supports: an optional /r modifier, print the
1190 raw instructions in hex as well as in symbolic form, and an optional /m
1191 modifier to print mixed source+assembly.
1193 * Process record and replay
1195 In a architecture environment that supports ``process record and
1196 replay'', ``process record and replay'' target can record a log of
1197 the process execution, and replay it with both forward and reverse
1200 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1201 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1202 set execution-direction {forward|reverse}, for targets that support
1205 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1206 feature is available with a native GDB running on kernel version
1209 * GDB now has support for multi-byte and wide character sets on the
1210 target. Strings whose character type is wchar_t, char16_t, or
1211 char32_t are now correctly printed. GDB supports wide- and unicode-
1212 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1213 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1214 `printf'. This feature requires iconv to work properly; if your
1215 system does not have a working iconv, GDB can use GNU libiconv. See
1216 the installation instructions for more information.
1218 * GDB now supports automatic retrieval of shared library files from
1219 remote targets. To use this feature, specify a system root that begins
1220 with the `remote:' prefix, either via the `set sysroot' command or via
1221 the `--with-sysroot' configure-time option.
1223 * "info sharedlibrary" now takes an optional regex of libraries to show,
1224 and it now reports if a shared library has no debugging information.
1226 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1227 now complete on file names.
1229 * When completing in expressions, gdb will attempt to limit
1230 completions to allowable structure or union fields, where appropriate.
1231 For instance, consider:
1233 # struct example { int f1; double f2; };
1234 # struct example variable;
1237 If the user types TAB at the end of this command line, the available
1238 completions will be "f1" and "f2".
1240 * Inlined functions are now supported. They show up in backtraces, and
1241 the "step", "next", and "finish" commands handle them automatically.
1243 * GDB now supports the token-splicing (##) and stringification (#)
1244 operators when expanding macros. It also supports variable-arity
1247 * GDB now supports inspecting extra signal information, exported by
1248 the new $_siginfo convenience variable. The feature is currently
1249 implemented on linux ARM, i386 and amd64.
1251 * GDB can now display the VFP floating point registers and NEON vector
1252 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1253 can provide these registers (requires Linux 2.6.30 or later). Remote
1254 and simulator targets may also provide them.
1256 * New remote packets
1259 Search memory for a sequence of bytes.
1262 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1263 operation over reliable transport links. Use of this packet is
1264 controlled by the `set remote noack-packet' command.
1267 Kill the process with the specified process ID. Use this in preference
1268 to `k' when multiprocess protocol extensions are supported.
1271 Obtains additional operating system information
1275 Read or write additional signal information.
1277 * Removed remote protocol undocumented extension
1279 An undocumented extension to the remote protocol's `S' stop reply
1280 packet that permited the stub to pass a process id was removed.
1281 Remote servers should use the `T' stop reply packet instead.
1283 * GDB now supports multiple function calling conventions according to the
1284 DWARF-2 DW_AT_calling_convention function attribute.
1286 * The SH target utilizes the aforementioned change to distinguish between gcc
1287 and Renesas calling convention. It also adds the new CLI commands
1288 `set/show sh calling-convention'.
1290 * GDB can now read compressed debug sections, as produced by GNU gold
1291 with the --compress-debug-sections=zlib flag.
1293 * 64-bit core files are now supported on AIX.
1295 * Thread switching is now supported on Tru64.
1297 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1298 which will be allocated using malloc later in program execution.
1300 * The qXfer:libraries:read remote procotol packet now allows passing a
1301 list of section offsets.
1303 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1304 conditions handling signals delivered during attach or thread creation
1305 have also been fixed.
1307 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1308 From the user's standpoint, all unqualified instances of True and False
1309 are treated as the standard definitions, regardless of context.
1311 * GDB now parses C++ symbol and type names more flexibly. For
1314 template<typename T> class C { };
1317 GDB will now correctly handle all of:
1319 ptype C<char const *>
1320 ptype C<char const*>
1321 ptype C<const char *>
1322 ptype C<const char*>
1324 * New features in the GDB remote stub, gdbserver
1326 - The "--wrapper" command-line argument tells gdbserver to use a
1327 wrapper program to launch programs for debugging.
1329 - On PowerPC and S/390 targets, it is now possible to use a single
1330 gdbserver executable to debug both 32-bit and 64-bit programs.
1331 (This requires gdbserver itself to be built as a 64-bit executable.)
1333 - gdbserver uses the new noack protocol mode for TCP connections to
1334 reduce communications latency, if also supported and enabled in GDB.
1336 - Support for the sparc64-linux-gnu target is now included in
1339 - The amd64-linux build of gdbserver now supports debugging both
1340 32-bit and 64-bit programs.
1342 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1343 now support hardware watchpoints, and will use them automatically
1348 GDB now has support for scripting using Python. Whether this is
1349 available is determined at configure time.
1351 New GDB commands can now be written in Python.
1353 * Ada tasking support
1355 Ada tasks can now be inspected in GDB. The following commands have
1359 Print the list of Ada tasks.
1361 Print detailed information about task number N.
1363 Print the task number of the current task.
1365 Switch the context of debugging to task number N.
1367 * Support for user-defined prefixed commands. The "define" command can
1368 add new commands to existing prefixes, e.g. "target".
1370 * Multi-inferior, multi-process debugging.
1372 GDB now has generalized support for multi-inferior debugging. See
1373 "Debugging Multiple Inferiors" in the manual for more information.
1374 Although availability still depends on target support, the command
1375 set is more uniform now. The GNU/Linux specific multi-forks support
1376 has been migrated to this new framework. This implied some user
1377 visible changes; see "New commands" and also "Removed commands"
1380 * Target descriptions can now describe the target OS ABI. See the
1381 "Target Description Format" section in the user manual for more
1384 * Target descriptions can now describe "compatible" architectures
1385 to indicate that the target can execute applications for a different
1386 architecture in addition to those for the main target architecture.
1387 See the "Target Description Format" section in the user manual for
1390 * Multi-architecture debugging.
1392 GDB now includes general supports for debugging applications on
1393 hybrid systems that use more than one single processor architecture
1394 at the same time. Each such hybrid architecture still requires
1395 specific support to be added. The only hybrid architecture supported
1396 in this version of GDB is the Cell Broadband Engine.
1398 * GDB now supports integrated debugging of Cell/B.E. applications that
1399 use both the PPU and SPU architectures. To enable support for hybrid
1400 Cell/B.E. debugging, you need to configure GDB to support both the
1401 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1402 --enable-targets configure option.
1404 * Non-stop mode debugging.
1406 For some targets, GDB now supports an optional mode of operation in
1407 which you can examine stopped threads while other threads continue
1408 to execute freely. This is referred to as non-stop mode, with the
1409 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1410 section in the user manual for more information.
1412 To be able to support remote non-stop debugging, a remote stub needs
1413 to implement the non-stop mode remote protocol extensions, as
1414 described in the "Remote Non-Stop" section of the user manual. The
1415 GDB remote stub, gdbserver, has been adjusted to support these
1416 extensions on linux targets.
1418 * New commands (for set/show, see "New options" below)
1420 catch syscall [NAME(S) | NUMBER(S)]
1421 Catch system calls. Arguments, which should be names of system
1422 calls or their numbers, mean catch only those syscalls. Without
1423 arguments, every syscall will be caught. When the inferior issues
1424 any of the specified syscalls, GDB will stop and announce the system
1425 call, both when it is called and when its call returns. This
1426 feature is currently available with a native GDB running on the
1427 Linux Kernel, under the following architectures: x86, x86_64,
1428 PowerPC and PowerPC64.
1430 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1432 Search memory for a sequence of bytes.
1434 maint set python print-stack
1435 maint show python print-stack
1436 Show a stack trace when an error is encountered in a Python script.
1439 Invoke CODE by passing it to the Python interpreter.
1444 These allow macros to be defined, undefined, and listed
1448 Show operating system information about processes.
1451 List the inferiors currently under GDB's control.
1454 Switch focus to inferior number NUM.
1457 Detach from inferior number NUM.
1460 Kill inferior number NUM.
1464 set spu stop-on-load
1465 show spu stop-on-load
1466 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1468 set spu auto-flush-cache
1469 show spu auto-flush-cache
1470 Control whether to automatically flush the software-managed cache
1471 during Cell/B.E. debugging.
1473 set sh calling-convention
1474 show sh calling-convention
1475 Control the calling convention used when calling SH target functions.
1478 show debug timestamp
1479 Control display of timestamps with GDB debugging output.
1481 set disassemble-next-line
1482 show disassemble-next-line
1483 Control display of disassembled source lines or instructions when
1486 set remote noack-packet
1487 show remote noack-packet
1488 Set/show the use of remote protocol QStartNoAckMode packet. See above
1489 under "New remote packets."
1491 set remote query-attached-packet
1492 show remote query-attached-packet
1493 Control use of remote protocol `qAttached' (query-attached) packet.
1495 set remote read-siginfo-object
1496 show remote read-siginfo-object
1497 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1500 set remote write-siginfo-object
1501 show remote write-siginfo-object
1502 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1505 set remote reverse-continue
1506 show remote reverse-continue
1507 Control use of remote protocol 'bc' (reverse-continue) packet.
1509 set remote reverse-step
1510 show remote reverse-step
1511 Control use of remote protocol 'bs' (reverse-step) packet.
1513 set displaced-stepping
1514 show displaced-stepping
1515 Control displaced stepping mode. Displaced stepping is a way to
1516 single-step over breakpoints without removing them from the debuggee.
1517 Also known as "out-of-line single-stepping".
1520 show debug displaced
1521 Control display of debugging info for displaced stepping.
1523 maint set internal-error
1524 maint show internal-error
1525 Control what GDB does when an internal error is detected.
1527 maint set internal-warning
1528 maint show internal-warning
1529 Control what GDB does when an internal warning is detected.
1534 Use a wrapper program to launch programs for debugging.
1536 set multiple-symbols (all|ask|cancel)
1537 show multiple-symbols
1538 The value of this variable can be changed to adjust the debugger behavior
1539 when an expression or a breakpoint location contains an ambiguous symbol
1540 name (an overloaded function name, for instance).
1542 set breakpoint always-inserted
1543 show breakpoint always-inserted
1544 Keep breakpoints always inserted in the target, as opposed to inserting
1545 them when resuming the target, and removing them when the target stops.
1546 This option can improve debugger performance on slow remote targets.
1548 set arm fallback-mode (arm|thumb|auto)
1549 show arm fallback-mode
1550 set arm force-mode (arm|thumb|auto)
1552 These commands control how ARM GDB determines whether instructions
1553 are ARM or Thumb. The default for both settings is auto, which uses
1554 the current CPSR value for instructions without symbols; previous
1555 versions of GDB behaved as if "set arm fallback-mode arm".
1557 set disable-randomization
1558 show disable-randomization
1559 Standalone programs run with the virtual address space randomization enabled
1560 by default on some platforms. This option keeps the addresses stable across
1561 multiple debugging sessions.
1565 Control whether other threads are stopped or not when some thread hits
1570 Requests that asynchronous execution is enabled in the target, if available.
1571 In this case, it's possible to resume target in the background, and interact
1572 with GDB while the target is running. "show target-async" displays the
1573 current state of asynchronous execution of the target.
1575 set target-wide-charset
1576 show target-wide-charset
1577 The target-wide-charset is the name of the character set that GDB
1578 uses when printing characters whose type is wchar_t.
1580 set tcp auto-retry (on|off)
1582 set tcp connect-timeout
1583 show tcp connect-timeout
1584 These commands allow GDB to retry failed TCP connections to a remote stub
1585 with a specified timeout period; this is useful if the stub is launched
1586 in parallel with GDB but may not be ready to accept connections immediately.
1588 set libthread-db-search-path
1589 show libthread-db-search-path
1590 Control list of directories which GDB will search for appropriate
1593 set schedule-multiple (on|off)
1594 show schedule-multiple
1595 Allow GDB to resume all threads of all processes or only threads of
1596 the current process.
1600 Use more aggressive caching for accesses to the stack. This improves
1601 performance of remote debugging (particularly backtraces) without
1602 affecting correctness.
1604 set interactive-mode (on|off|auto)
1605 show interactive-mode
1606 Control whether GDB runs in interactive mode (on) or not (off).
1607 When in interactive mode, GDB waits for the user to answer all
1608 queries. Otherwise, GDB does not wait and assumes the default
1609 answer. When set to auto (the default), GDB determines which
1610 mode to use based on the stdin settings.
1615 For program forks, this is replaced by the new more generic `info
1616 inferiors' command. To list checkpoints, you can still use the
1617 `info checkpoints' command, which was an alias for the `info forks'
1621 Replaced by the new `inferior' command. To switch between
1622 checkpoints, you can still use the `restart' command, which was an
1623 alias for the `fork' command.
1626 This is removed, since some targets don't have a notion of
1627 processes. To switch between processes, you can still use the
1628 `inferior' command using GDB's own inferior number.
1631 For program forks, this is replaced by the new more generic `kill
1632 inferior' command. To delete a checkpoint, you can still use the
1633 `delete checkpoint' command, which was an alias for the `delete
1637 For program forks, this is replaced by the new more generic `detach
1638 inferior' command. To detach a checkpoint, you can still use the
1639 `detach checkpoint' command, which was an alias for the `detach
1642 * New native configurations
1644 x86/x86_64 Darwin i[34567]86-*-darwin*
1646 x86_64 MinGW x86_64-*-mingw*
1650 Lattice Mico32 lm32-*
1651 x86 DICOS i[34567]86-*-dicos*
1652 x86_64 DICOS x86_64-*-dicos*
1655 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1656 (mingw32ce) debugging.
1662 These commands were actually not implemented on any target.
1664 *** Changes in GDB 6.8
1666 * New native configurations
1668 NetBSD/hppa hppa*-*netbsd*
1669 Xtensa GNU/Linux xtensa*-*-linux*
1673 NetBSD/hppa hppa*-*-netbsd*
1674 Xtensa GNU/Lunux xtensa*-*-linux*
1676 * Change in command line behavior -- corefiles vs. process ids.
1678 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1679 attaching to process NUMBER fails, GDB no longer attempts to open a
1680 core file named NUMBER. Attaching to a program using the -c option
1681 is no longer supported. Instead, use the '-p' or '--pid' options.
1683 * GDB can now be built as a native debugger for debugging Windows x86
1684 (mingw32) Portable Executable (PE) programs.
1686 * Pending breakpoints no longer change their number when their address
1689 * GDB now supports breakpoints with multiple locations,
1690 including breakpoints on C++ constructors, inside C++ templates,
1691 and in inlined functions.
1693 * GDB's ability to debug optimized code has been improved. GDB more
1694 accurately identifies function bodies and lexical blocks that occupy
1695 more than one contiguous range of addresses.
1697 * Target descriptions can now describe registers for PowerPC.
1699 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1700 registers on PowerPC targets.
1702 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1703 targets even when the libthread_db library is not available.
1705 * The GDB remote stub, gdbserver, now supports the new file transfer
1706 commands (remote put, remote get, and remote delete).
1708 * The GDB remote stub, gdbserver, now supports run and attach in
1709 extended-remote mode.
1711 * hppa*64*-*-hpux11* target broken
1712 The debugger is unable to start a program and fails with the following
1713 error: "Error trying to get information about dynamic linker".
1714 The gdb-6.7 release is also affected.
1716 * GDB now supports the --enable-targets= configure option to allow
1717 building a single GDB executable that supports multiple remote
1718 target architectures.
1720 * GDB now supports debugging C and C++ programs which use the
1721 Decimal Floating Point extension. In addition, the PowerPC target
1722 now has a set of pseudo-registers to inspect decimal float values
1723 stored in two consecutive float registers.
1725 * The -break-insert MI command can optionally create pending
1728 * Improved support for debugging Ada
1729 Many improvements to the Ada language support have been made. These
1731 - Better support for Ada2005 interface types
1732 - Improved handling of arrays and slices in general
1733 - Better support for Taft-amendment types
1734 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1736 - Improved command completion in Ada
1739 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1744 set print frame-arguments (all|scalars|none)
1745 show print frame-arguments
1746 The value of this variable can be changed to control which argument
1747 values should be printed by the debugger when displaying a frame.
1752 Transfer files to and from a remote target, and delete remote files.
1759 Transfer files to and from a remote target, and delete remote files.
1761 * New remote packets
1768 Open, close, read, write, and delete files on the remote system.
1771 Attach to an existing process on the remote system, in extended-remote
1775 Run a new process on the remote system, in extended-remote mode.
1777 *** Changes in GDB 6.7
1779 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1780 bfd, libiberty and opcodes, as revealed by static analysis donated by
1781 Coverity, Inc. (http://scan.coverity.com).
1783 * When looking up multiply-defined global symbols, GDB will now prefer the
1784 symbol definition in the current shared library if it was built using the
1785 -Bsymbolic linker option.
1787 * When the Text User Interface (TUI) is not configured, GDB will now
1788 recognize the -tui command-line option and print a message that the TUI
1791 * The GDB remote stub, gdbserver, now has lower overhead for high
1792 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1794 * GDB for MIPS targets now autodetects whether a remote target provides
1795 32-bit or 64-bit register values.
1797 * Support for C++ member pointers has been improved.
1799 * GDB now understands XML target descriptions, which specify the
1800 target's overall architecture. GDB can read a description from
1801 a local file or over the remote serial protocol.
1803 * Vectors of single-byte data use a new integer type which is not
1804 automatically displayed as character or string data.
1806 * The /s format now works with the print command. It displays
1807 arrays of single-byte integers and pointers to single-byte integers
1810 * Target descriptions can now describe target-specific registers,
1811 for architectures which have implemented the support (currently
1812 only ARM, M68K, and MIPS).
1814 * GDB and the GDB remote stub, gdbserver, now support the XScale
1817 * The GDB remote stub, gdbserver, has been updated to support
1818 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1819 has been rewritten to use the standard GDB remote protocol.
1821 * GDB can now step into C++ functions which are called through thunks.
1823 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1825 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1826 layout. It also supports a TextSeg= and DataSeg= response when only
1827 segment base addresses (rather than offsets) are available.
1829 * The /i format now outputs any trailing branch delay slot instructions
1830 immediately following the last instruction within the count specified.
1832 * The GDB remote protocol "T" stop reply packet now supports a
1833 "library" response. Combined with the new "qXfer:libraries:read"
1834 packet, this response allows GDB to debug shared libraries on targets
1835 where the operating system manages the list of loaded libraries (e.g.
1836 Windows and SymbianOS).
1838 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1839 (DLLs) on Windows and Windows CE targets.
1841 * GDB now supports a faster verification that a .debug file matches its binary
1842 according to its build-id signature, if the signature is present.
1848 Enable or disable hardware flow control (RTS/CTS) on the serial port
1849 when debugging using remote targets.
1851 set mem inaccessible-by-default
1852 show mem inaccessible-by-default
1853 If the target supplies a memory map, for instance via the remote
1854 protocol's "qXfer:memory-map:read" packet, setting this variable
1855 prevents GDB from accessing memory outside the memory map. This
1856 is useful for targets with memory mapped registers or which react
1857 badly to accesses of unmapped address space.
1859 set breakpoint auto-hw
1860 show breakpoint auto-hw
1861 If the target supplies a memory map, for instance via the remote
1862 protocol's "qXfer:memory-map:read" packet, setting this variable
1863 lets GDB use hardware breakpoints automatically for memory regions
1864 where it can not use software breakpoints. This covers both the
1865 "break" command and internal breakpoints used for other commands
1866 including "next" and "finish".
1869 catch exception unhandled
1870 Stop the program execution when Ada exceptions are raised.
1873 Stop the program execution when an Ada assertion failed.
1877 Set an alternate system root for target files. This is a more
1878 general version of "set solib-absolute-prefix", which is now
1879 an alias to "set sysroot".
1882 Provide extended SPU facility status information. This set of
1883 commands is available only when debugging the Cell/B.E. SPU
1886 * New native configurations
1888 OpenBSD/sh sh*-*openbsd*
1891 unset tdesc filename
1893 Use the specified local file as an XML target description, and do
1894 not query the target for its built-in description.
1898 OpenBSD/sh sh*-*-openbsd*
1899 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1900 Toshiba Media Processor mep-elf
1902 * New remote packets
1905 Ignore the specified signals; pass them directly to the debugged program
1906 without stopping other threads or reporting them to GDB.
1908 qXfer:features:read:
1909 Read an XML target description from the target, which describes its
1914 Read or write contents of an spufs file on the target system. These
1915 packets are available only on the Cell/B.E. SPU architecture.
1917 qXfer:libraries:read:
1918 Report the loaded shared libraries. Combined with new "T" packet
1919 response, this packet allows GDB to debug shared libraries on
1920 targets where the operating system manages the list of loaded
1921 libraries (e.g. Windows and SymbianOS).
1925 Support for these obsolete configurations has been removed.
1933 i[34567]86-*-lynxos*
1934 i[34567]86-*-netware*
1935 i[34567]86-*-sco3.2v5*
1936 i[34567]86-*-sco3.2v4*
1938 i[34567]86-*-sysv4.2*
1941 i[34567]86-*-unixware2*
1942 i[34567]86-*-unixware*
1951 * Other removed features
1958 Various m68k-only ROM monitors.
1965 Various Renesas ROM monitors and debugging interfaces for SH and
1970 Support for a Macraigor serial interface to on-chip debugging.
1971 GDB does not directly support the newer parallel or USB
1976 A debug information format. The predecessor to DWARF 2 and
1977 DWARF 3, which are still supported.
1979 Support for the HP aCC compiler on HP-UX/PA-RISC
1981 SOM-encapsulated symbolic debugging information, automatic
1982 invocation of pxdb, and the aCC custom C++ ABI. This does not
1983 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1984 with aCC can still be debugged on an assembly level.
1986 MIPS ".pdr" sections
1988 A MIPS-specific format used to describe stack frame layout
1989 in debugging information.
1993 GDB could work with an older version of Guile to debug
1994 the interpreter and Scheme programs running in it.
1996 set mips stack-arg-size
1997 set mips saved-gpreg-size
1999 Use "set mips abi" to control parameter passing for MIPS.
2001 *** Changes in GDB 6.6
2006 Cell Broadband Engine SPU spu-elf
2008 * GDB can now be configured as a cross-debugger targeting native Windows
2009 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2010 running on a Windows system over TCP/IP to debug Windows programs.
2012 * The GDB remote stub, gdbserver, has been updated to support Windows and
2013 Cygwin debugging. Both single-threaded and multi-threaded programs are
2016 * The "set trust-readonly-sections" command works again. This command was
2017 broken in GDB 6.3, 6.4, and 6.5.
2019 * The "load" command now supports writing to flash memory, if the remote
2020 stub provides the required support.
2022 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2023 longer requires symbolic debug information (e.g. DWARF-2).
2028 unset substitute-path
2029 show substitute-path
2030 Manage a list of substitution rules that GDB uses to rewrite the name
2031 of the directories where the sources are located. This can be useful
2032 for instance when the sources were moved to a different location
2033 between compilation and debugging.
2037 Print each CLI command as it is executed. Each command is prefixed with
2038 a number of `+' symbols representing the nesting depth.
2039 The source command now has a `-v' option to enable the same feature.
2043 The ARM Demon monitor support (RDP protocol, "target rdp").
2045 Kernel Object Display, an embedded debugging feature which only worked with
2046 an obsolete version of Cisco IOS.
2048 The 'set download-write-size' and 'show download-write-size' commands.
2050 * New remote packets
2053 Tell a stub about GDB client features, and request remote target features.
2054 The first feature implemented is PacketSize, which allows the target to
2055 specify the size of packets it can handle - to minimize the number of
2056 packets required and improve performance when connected to a remote
2060 Fetch an OS auxilliary vector from the remote stub. This packet is a
2061 more efficient replacement for qPart:auxv:read.
2063 qXfer:memory-map:read:
2064 Fetch a memory map from the remote stub, including information about
2065 RAM, ROM, and flash memory devices.
2070 Erase and program a flash memory device.
2072 * Removed remote packets
2075 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2076 used it, and only gdbserver implemented it.
2078 *** Changes in GDB 6.5
2082 Renesas M32C/M16C m32c-elf
2084 Morpho Technologies ms1 ms1-elf
2088 init-if-undefined Initialize a convenience variable, but
2089 only if it doesn't already have a value.
2091 The following commands are presently only implemented for native GNU/Linux:
2093 checkpoint Save a snapshot of the program state.
2095 restart <n> Return the program state to a
2096 previously saved state.
2098 info checkpoints List currently saved checkpoints.
2100 delete-checkpoint <n> Delete a previously saved checkpoint.
2102 set|show detach-on-fork Tell gdb whether to detach from a newly
2103 forked process, or to keep debugging it.
2105 info forks List forks of the user program that
2106 are available to be debugged.
2108 fork <n> Switch to debugging one of several
2109 forks of the user program that are
2110 available to be debugged.
2112 delete-fork <n> Delete a fork from the list of forks
2113 that are available to be debugged (and
2114 kill the forked process).
2116 detach-fork <n> Delete a fork from the list of forks
2117 that are available to be debugged (and
2118 allow the process to continue).
2122 Morpho Technologies ms2 ms1-elf
2124 * Improved Windows host support
2126 GDB now builds as a cross debugger hosted on i686-mingw32, including
2127 native console support, and remote communications using either
2128 network sockets or serial ports.
2130 * Improved Modula-2 language support
2132 GDB can now print most types in the Modula-2 syntax. This includes:
2133 basic types, set types, record types, enumerated types, range types,
2134 pointer types and ARRAY types. Procedure var parameters are correctly
2135 printed and hexadecimal addresses and character constants are also
2136 written in the Modula-2 syntax. Best results can be obtained by using
2137 GNU Modula-2 together with the -gdwarf-2 command line option.
2141 The ARM rdi-share module.
2143 The Netware NLM debug server.
2145 *** Changes in GDB 6.4
2147 * New native configurations
2149 OpenBSD/arm arm*-*-openbsd*
2150 OpenBSD/mips64 mips64-*-openbsd*
2154 Morpho Technologies ms1 ms1-elf
2156 * New command line options
2158 --batch-silent As for --batch, but totally silent.
2159 --return-child-result The debugger will exist with the same value
2160 the child (debugged) program exited with.
2161 --eval-command COMMAND, -ex COMMAND
2162 Execute a single GDB CLI command. This may be
2163 specified multiple times and in conjunction
2164 with the --command (-x) option.
2166 * Deprecated commands removed
2168 The following commands, that were deprecated in 2000, have been
2172 set|show arm disassembly-flavor set|show arm disassembler
2173 othernames set arm disassembler
2174 set|show remotedebug set|show debug remote
2175 set|show archdebug set|show debug arch
2176 set|show eventdebug set|show debug event
2179 * New BSD user-level threads support
2181 It is now possible to debug programs using the user-level threads
2182 library on OpenBSD and FreeBSD. Currently supported (target)
2185 FreeBSD/amd64 x86_64-*-freebsd*
2186 FreeBSD/i386 i386-*-freebsd*
2187 OpenBSD/i386 i386-*-openbsd*
2189 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2190 are not yet supported.
2192 * New support for Matsushita MN10300 w/sim added
2193 (Work in progress). mn10300-elf.
2195 * REMOVED configurations and files
2197 VxWorks and the XDR protocol *-*-vxworks
2198 Motorola MCORE mcore-*-*
2199 National Semiconductor NS32000 ns32k-*-*
2201 * New "set print array-indexes" command
2203 After turning this setting "on", GDB prints the index of each element
2204 when displaying arrays. The default is "off" to preserve the previous
2207 * VAX floating point support
2209 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2211 * User-defined command support
2213 In addition to using $arg0..$arg9 for argument passing, it is now possible
2214 to use $argc to determine now many arguments have been passed. See the
2215 section on user-defined commands in the user manual for more information.
2217 *** Changes in GDB 6.3:
2219 * New command line option
2221 GDB now accepts -l followed by a number to set the timeout for remote
2224 * GDB works with GCC -feliminate-dwarf2-dups
2226 GDB now supports a more compact representation of DWARF-2 debug
2227 information using DW_FORM_ref_addr references. These are produced
2228 by GCC with the option -feliminate-dwarf2-dups and also by some
2229 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2230 to use -feliminate-dwarf2-dups.
2232 * Internationalization
2234 When supported by the host system, GDB will be built with
2235 internationalization (libintl). The task of marking up the sources is
2236 continued, we're looking forward to our first translation.
2240 Initial support for debugging programs compiled with the GNAT
2241 implementation of the Ada programming language has been integrated
2242 into GDB. In this release, support is limited to expression evaluation.
2244 * New native configurations
2246 GNU/Linux/m32r m32r-*-linux-gnu
2250 GDB's remote protocol now includes support for the 'p' packet. This
2251 packet is used to fetch individual registers from a remote inferior.
2253 * END-OF-LIFE registers[] compatibility module
2255 GDB's internal register infrastructure has been completely rewritten.
2256 The new infrastructure making possible the implementation of key new
2257 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2260 GDB 6.3 will be the last release to include the the registers[]
2261 compatibility module that allowed out-of-date configurations to
2262 continue to work. This change directly impacts the following
2272 powerpc bdm protocol
2274 Unless there is activity to revive these configurations, they will be
2275 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2277 * OBSOLETE configurations and files
2279 Configurations that have been declared obsolete in this release have
2280 been commented out. Unless there is activity to revive these
2281 configurations, the next release of GDB will have their sources
2282 permanently REMOVED.
2291 *** Changes in GDB 6.2.1:
2293 * MIPS `break main; run' gave an heuristic-fence-post warning
2295 When attempting to run even a simple program, a warning about
2296 heuristic-fence-post being hit would be reported. This problem has
2299 * MIPS IRIX 'long double' crashed GDB
2301 When examining a long double variable, GDB would get a segmentation
2302 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2303 IRIX long double values).
2307 A bug in the VAX stack code was causing problems with the "next"
2308 command. This problem has been fixed.
2310 *** Changes in GDB 6.2:
2312 * Fix for ``many threads''
2314 On GNU/Linux systems that use the NPTL threads library, a program
2315 rapidly creating and deleting threads would confuse GDB leading to the
2318 ptrace: No such process.
2319 thread_db_get_info: cannot get thread info: generic error
2321 This problem has been fixed.
2323 * "-async" and "-noasync" options removed.
2325 Support for the broken "-noasync" option has been removed (it caused
2328 * New ``start'' command.
2330 This command runs the program until the begining of the main procedure.
2332 * New BSD Kernel Data Access Library (libkvm) interface
2334 Using ``target kvm'' it is now possible to debug kernel core dumps and
2335 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2336 platforms. Currently supported (native-only) configurations are:
2338 FreeBSD/amd64 x86_64-*-freebsd*
2339 FreeBSD/i386 i?86-*-freebsd*
2340 NetBSD/i386 i?86-*-netbsd*
2341 NetBSD/m68k m68*-*-netbsd*
2342 NetBSD/sparc sparc-*-netbsd*
2343 OpenBSD/amd64 x86_64-*-openbsd*
2344 OpenBSD/i386 i?86-*-openbsd*
2345 OpenBSD/m68k m68*-openbsd*
2346 OpenBSD/sparc sparc-*-openbsd*
2348 * Signal trampoline code overhauled
2350 Many generic problems with GDB's signal handling code have been fixed.
2351 These include: backtraces through non-contiguous stacks; recognition
2352 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2353 call; backtrace through a signal trampoline; step into and out of
2354 signal handlers; and single-stepping in the signal trampoline.
2356 Please note that kernel bugs are a limiting factor here. These
2357 features have been shown to work on an s390 GNU/Linux system that
2358 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2360 * Cygwin support for DWARF 2 added.
2362 * New native configurations
2364 GNU/Linux/hppa hppa*-*-linux*
2365 OpenBSD/hppa hppa*-*-openbsd*
2366 OpenBSD/m68k m68*-*-openbsd*
2367 OpenBSD/m88k m88*-*-openbsd*
2368 OpenBSD/powerpc powerpc-*-openbsd*
2369 NetBSD/vax vax-*-netbsd*
2370 OpenBSD/vax vax-*-openbsd*
2372 * END-OF-LIFE frame compatibility module
2374 GDB's internal frame infrastructure has been completely rewritten.
2375 The new infrastructure making it possible to support key new features
2376 including DWARF 2 Call Frame Information. To aid in the task of
2377 migrating old configurations to this new infrastructure, a
2378 compatibility module, that allowed old configurations to continue to
2379 work, was also included.
2381 GDB 6.2 will be the last release to include this frame compatibility
2382 module. This change directly impacts the following configurations:
2392 Unless there is activity to revive these configurations, they will be
2393 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2395 * REMOVED configurations and files
2397 Sun 3, running SunOS 3 m68*-*-sunos3*
2398 Sun 3, running SunOS 4 m68*-*-sunos4*
2399 Sun 2, running SunOS 3 m68000-*-sunos3*
2400 Sun 2, running SunOS 4 m68000-*-sunos4*
2401 Motorola 680x0 running LynxOS m68*-*-lynxos*
2402 AT&T 3b1/Unix pc m68*-att-*
2403 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2404 decstation mips-dec-* mips-little-*
2405 riscos mips-*-riscos* mips-*-sysv*
2406 sonymips mips-sony-*
2407 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2409 *** Changes in GDB 6.1.1:
2411 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2413 The TUI (Text-mode User Interface) is now built as part of a default
2414 GDB configuration. It is enabled by either selecting the TUI with the
2415 command line option "-i=tui" or by running the separate "gdbtui"
2416 program. For more information on the TUI, see the manual "Debugging
2419 * Pending breakpoint support (also included in GDB 6.1)
2421 Support has been added to allow you to specify breakpoints in shared
2422 libraries that have not yet been loaded. If a breakpoint location
2423 cannot be found, and the "breakpoint pending" option is set to auto,
2424 GDB queries you if you wish to make the breakpoint pending on a future
2425 shared-library load. If and when GDB resolves the breakpoint symbol,
2426 the pending breakpoint is removed as one or more regular breakpoints
2429 Pending breakpoints are very useful for GCJ Java debugging.
2431 * Fixed ISO-C build problems
2433 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2434 non ISO-C code that stopped them being built using a more strict ISO-C
2435 compiler (e.g., IBM's C compiler).
2437 * Fixed build problem on IRIX 5
2439 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2440 wasn't able to compile compile on an IRIX 5 system.
2442 * Added execute permission to gdb/gdbserver/configure
2444 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2445 permission. This bug would cause configure to fail on a number of
2446 systems (Solaris, IRIX). Ref: server/519.
2448 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2450 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2451 has been updated to use constant array sizes.
2453 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2455 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2456 its generated DWARF Call Frame Info. This encoding was causing GDB to
2457 panic, that panic has been fixed. Ref: gdb/1628.
2459 * Fixed a problem when examining parameters in shared library code.
2461 When examining parameters in optimized shared library code generated
2462 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2463 not available''. GDB now correctly displays the variable's value.
2465 *** Changes in GDB 6.1:
2467 * Removed --with-mmalloc
2469 Support for the mmalloc memory manager has been removed, as it
2470 conflicted with the internal gdb byte cache.
2472 * Changes in AMD64 configurations
2474 The AMD64 target now includes the %cs and %ss registers. As a result
2475 the AMD64 remote protocol has changed; this affects the floating-point
2476 and SSE registers. If you rely on those registers for your debugging,
2477 you should upgrade gdbserver on the remote side.
2479 * Revised SPARC target
2481 The SPARC target has been completely revised, incorporating the
2482 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2483 support for LynxOS and SunOS 4 has been dropped. Calling functions
2484 from within GDB on operating systems with a non-executable stack
2485 (Solaris, OpenBSD) now works.
2489 GDB has a new C++ demangler which does a better job on the mangled
2490 names generated by current versions of g++. It also runs faster, so
2491 with this and other changes gdb should now start faster on large C++
2494 * DWARF 2 Location Expressions
2496 GDB support for location expressions has been extended to support function
2497 arguments and frame bases. Older versions of GDB could crash when they
2500 * C++ nested types and namespaces
2502 GDB's support for nested types and namespaces in C++ has been
2503 improved, especially if you use the DWARF 2 debugging format. (This
2504 is the default for recent versions of GCC on most platforms.)
2505 Specifically, if you have a class "Inner" defined within a class or
2506 namespace "Outer", then GDB realizes that the class's name is
2507 "Outer::Inner", not simply "Inner". This should greatly reduce the
2508 frequency of complaints about not finding RTTI symbols. In addition,
2509 if you are stopped at inside of a function defined within a namespace,
2510 GDB modifies its name lookup accordingly.
2512 * New native configurations
2514 NetBSD/amd64 x86_64-*-netbsd*
2515 OpenBSD/amd64 x86_64-*-openbsd*
2516 OpenBSD/alpha alpha*-*-openbsd*
2517 OpenBSD/sparc sparc-*-openbsd*
2518 OpenBSD/sparc64 sparc64-*-openbsd*
2520 * New debugging protocols
2522 M32R with SDI protocol m32r-*-elf*
2524 * "set prompt-escape-char" command deleted.
2526 The command "set prompt-escape-char" has been deleted. This command,
2527 and its very obscure effet on GDB's prompt, was never documented,
2528 tested, nor mentioned in the NEWS file.
2530 * OBSOLETE configurations and files
2532 Configurations that have been declared obsolete in this release have
2533 been commented out. Unless there is activity to revive these
2534 configurations, the next release of GDB will have their sources
2535 permanently REMOVED.
2537 Sun 3, running SunOS 3 m68*-*-sunos3*
2538 Sun 3, running SunOS 4 m68*-*-sunos4*
2539 Sun 2, running SunOS 3 m68000-*-sunos3*
2540 Sun 2, running SunOS 4 m68000-*-sunos4*
2541 Motorola 680x0 running LynxOS m68*-*-lynxos*
2542 AT&T 3b1/Unix pc m68*-att-*
2543 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2544 decstation mips-dec-* mips-little-*
2545 riscos mips-*-riscos* mips-*-sysv*
2546 sonymips mips-sony-*
2547 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2549 * REMOVED configurations and files
2551 SGI Irix-4.x mips-sgi-irix4 or iris4
2552 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2553 Z8000 simulator z8k-zilog-none or z8ksim
2554 Matsushita MN10200 w/simulator mn10200-*-*
2555 H8/500 simulator h8500-hitachi-hms or h8500hms
2556 HP/PA running BSD hppa*-*-bsd*
2557 HP/PA running OSF/1 hppa*-*-osf*
2558 HP/PA Pro target hppa*-*-pro*
2559 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2560 386BSD i[3456]86-*-bsd*
2561 Sequent family i[3456]86-sequent-sysv4*
2562 i[3456]86-sequent-sysv*
2563 i[3456]86-sequent-bsd*
2564 SPARC running LynxOS sparc-*-lynxos*
2565 SPARC running SunOS 4 sparc-*-sunos4*
2566 Tsqware Sparclet sparclet-*-*
2567 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2569 *** Changes in GDB 6.0:
2573 Support for debugging the Objective-C programming language has been
2574 integrated into GDB.
2576 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2578 DWARF 2's Call Frame Information makes available compiler generated
2579 information that more exactly describes the program's run-time stack.
2580 By using this information, GDB is able to provide more robust stack
2583 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2584 have been updated to use a new backtrace mechanism which includes
2585 DWARF 2 CFI support.
2589 GDB's remote protocol has been extended to include support for hosted
2590 file I/O (where the remote target uses GDB's file system). See GDB's
2591 remote protocol documentation for details.
2593 * All targets using the new architecture framework.
2595 All of GDB's targets have been updated to use the new internal
2596 architecture framework. The way is now open for future GDB releases
2597 to include cross-architecture native debugging support (i386 on amd64,
2600 * GNU/Linux's Thread Local Storage (TLS)
2602 GDB now includes support for for the GNU/Linux implementation of
2603 per-thread variables.
2605 * GNU/Linux's Native POSIX Thread Library (NPTL)
2607 GDB's thread code has been updated to work with either the new
2608 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2610 * Separate debug info.
2612 GDB, in conjunction with BINUTILS, now supports a mechanism for
2613 automatically loading debug information from a separate file. Instead
2614 of shipping full debug and non-debug versions of system libraries,
2615 system integrators can now instead ship just the stripped libraries
2616 and optional debug files.
2618 * DWARF 2 Location Expressions
2620 DWARF 2 Location Expressions allow the compiler to more completely
2621 describe the location of variables (even in optimized code) to the
2624 GDB now includes preliminary support for location expressions (support
2625 for DW_OP_piece is still missing).
2629 A number of long standing bugs that caused GDB to die while starting a
2630 Java application have been fixed. GDB's Java support is now
2631 considered "useable".
2633 * GNU/Linux support for fork, vfork, and exec.
2635 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2636 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2639 * GDB supports logging output to a file
2641 There are two new commands, "set logging" and "show logging", which can be
2642 used to capture GDB's output to a file.
2644 * The meaning of "detach" has changed for gdbserver
2646 The "detach" command will now resume the application, as documented. To
2647 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2650 * d10v, m68hc11 `regs' command deprecated
2652 The `info registers' command has been updated so that it displays the
2653 registers using a format identical to the old `regs' command.
2657 A new command, "maint set profile on/off", has been added. This command can
2658 be used to enable or disable profiling while running GDB, to profile a
2659 session or a set of commands. In addition there is a new configure switch,
2660 "--enable-profiling", which will cause GDB to be compiled with profiling
2661 data, for more informative profiling results.
2663 * Default MI syntax changed to "mi2".
2665 The default MI (machine interface) syntax, enabled by the command line
2666 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2667 "mi1", can be enabled by specifying the option "-i=mi1".
2669 Support for the original "mi0" syntax (included in GDB 5.0) has been
2672 Fix for gdb/192: removed extraneous space when displaying frame level.
2673 Fix for gdb/672: update changelist is now output in mi list format.
2674 Fix for gdb/702: a -var-assign that updates the value now shows up
2675 in a subsequent -var-update.
2677 * New native configurations.
2679 FreeBSD/amd64 x86_64-*-freebsd*
2681 * Multi-arched targets.
2683 HP/PA HPUX11 hppa*-*-hpux*
2684 Renesas M32R/D w/simulator m32r-*-elf*
2686 * OBSOLETE configurations and files
2688 Configurations that have been declared obsolete in this release have
2689 been commented out. Unless there is activity to revive these
2690 configurations, the next release of GDB will have their sources
2691 permanently REMOVED.
2693 Z8000 simulator z8k-zilog-none or z8ksim
2694 Matsushita MN10200 w/simulator mn10200-*-*
2695 H8/500 simulator h8500-hitachi-hms or h8500hms
2696 HP/PA running BSD hppa*-*-bsd*
2697 HP/PA running OSF/1 hppa*-*-osf*
2698 HP/PA Pro target hppa*-*-pro*
2699 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2700 Sequent family i[3456]86-sequent-sysv4*
2701 i[3456]86-sequent-sysv*
2702 i[3456]86-sequent-bsd*
2703 Tsqware Sparclet sparclet-*-*
2704 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2706 * REMOVED configurations and files
2709 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2710 IBM AIX PS/2 i[3456]86-*-aix
2711 i386 running Mach 3.0 i[3456]86-*-mach3*
2712 i386 running Mach i[3456]86-*-mach*
2713 i386 running OSF/1 i[3456]86-*osf1mk*
2714 HP/Apollo 68k Family m68*-apollo*-sysv*,
2716 m68*-hp-bsd*, m68*-hp-hpux*
2717 Argonaut Risc Chip (ARC) arc-*-*
2718 Mitsubishi D30V d30v-*-*
2719 Fujitsu FR30 fr30-*-elf*
2720 OS/9000 i[34]86-*-os9k
2721 I960 with MON960 i960-*-coff
2723 * MIPS $fp behavior changed
2725 The convenience variable $fp, for the MIPS, now consistently returns
2726 the address of the current frame's base. Previously, depending on the
2727 context, $fp could refer to either $sp or the current frame's base
2728 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2729 The GNU Source-Level Debugger''.
2731 *** Changes in GDB 5.3:
2733 * GNU/Linux shared library multi-threaded performance improved.
2735 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2736 `/proc', in preference to `ptrace' for memory reads. This may result
2737 in an improvement in the start-up time of multi-threaded, shared
2738 library applications when run under GDB. One GDB user writes: ``loads
2739 shared libs like mad''.
2741 * ``gdbserver'' now supports multi-threaded applications on some targets
2743 Support for debugging multi-threaded applications which use
2744 the GNU/Linux LinuxThreads package has been added for
2745 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2746 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2748 * GDB now supports C/C++ preprocessor macros.
2750 GDB now expands preprocessor macro invocations in C/C++ expressions,
2751 and provides various commands for showing macro definitions and how
2754 The new command `macro expand EXPRESSION' expands any macro
2755 invocations in expression, and shows the result.
2757 The new command `show macro MACRO-NAME' shows the definition of the
2758 macro named MACRO-NAME, and where it was defined.
2760 Most compilers don't include information about macros in the debugging
2761 information by default. In GCC 3.1, for example, you need to compile
2762 your program with the options `-gdwarf-2 -g3'. If the macro
2763 information is present in the executable, GDB will read it.
2765 * Multi-arched targets.
2767 DEC Alpha (partial) alpha*-*-*
2768 DEC VAX (partial) vax-*-*
2770 National Semiconductor NS32000 (partial) ns32k-*-*
2771 Motorola 68000 (partial) m68k-*-*
2772 Motorola MCORE mcore-*-*
2776 Fujitsu FRV architecture added by Red Hat frv*-*-*
2779 * New native configurations
2781 Alpha NetBSD alpha*-*-netbsd*
2782 SH NetBSD sh*-*-netbsdelf*
2783 MIPS NetBSD mips*-*-netbsd*
2784 UltraSPARC NetBSD sparc64-*-netbsd*
2786 * OBSOLETE configurations and files
2788 Configurations that have been declared obsolete in this release have
2789 been commented out. Unless there is activity to revive these
2790 configurations, the next release of GDB will have their sources
2791 permanently REMOVED.
2793 Mitsubishi D30V d30v-*-*
2794 OS/9000 i[34]86-*-os9k
2795 IBM AIX PS/2 i[3456]86-*-aix
2796 Fujitsu FR30 fr30-*-elf*
2797 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2798 Argonaut Risc Chip (ARC) arc-*-*
2799 i386 running Mach 3.0 i[3456]86-*-mach3*
2800 i386 running Mach i[3456]86-*-mach*
2801 i386 running OSF/1 i[3456]86-*osf1mk*
2802 HP/Apollo 68k Family m68*-apollo*-sysv*,
2804 m68*-hp-bsd*, m68*-hp-hpux*
2805 I960 with MON960 i960-*-coff
2807 * OBSOLETE languages
2809 CHILL, a Pascal like language used by telecommunications companies.
2811 * REMOVED configurations and files
2813 AMD 29k family via UDI a29k-amd-udi, udi29k
2814 A29K VxWorks a29k-*-vxworks
2815 AMD 29000 embedded, using EBMON a29k-none-none
2816 AMD 29000 embedded with COFF a29k-none-coff
2817 AMD 29000 embedded with a.out a29k-none-aout
2819 testsuite/gdb.hp/gdb.threads-hp/ directory
2821 * New command "set max-user-call-depth <nnn>"
2823 This command allows the user to limit the call depth of user-defined
2824 commands. The default is 1024.
2826 * Changes in FreeBSD/i386 native debugging.
2828 Support for the "generate-core-file" has been added.
2830 * New commands "dump", "append", and "restore".
2832 These commands allow data to be copied from target memory
2833 to a bfd-format or binary file (dump and append), and back
2834 from a file into memory (restore).
2836 * Improved "next/step" support on multi-processor Alpha Tru64.
2838 The previous single-step mechanism could cause unpredictable problems,
2839 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2840 of a software single-step mechanism prevents this.
2842 *** Changes in GDB 5.2.1:
2850 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2851 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2852 Fix, by Joel Brobecker imported from mainline.
2854 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2855 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2856 Fix, by Fred Fish, imported from mainline.
2858 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2859 Surprisingly enough, it works now.
2860 By Michal Ludvig, imported from mainline.
2862 i386 hardware watchpoint support:
2863 avoid misses on second run for some targets.
2864 By Pierre Muller, imported from mainline.
2866 *** Changes in GDB 5.2:
2868 * New command "set trust-readonly-sections on[off]".
2870 This command is a hint that tells gdb that read-only sections
2871 really are read-only (ie. that their contents will not change).
2872 In this mode, gdb will go to the object file rather than the
2873 target to read memory from read-only sections (such as ".text").
2874 This can be a significant performance improvement on some
2875 (notably embedded) targets.
2877 * New command "generate-core-file" (or "gcore").
2879 This new gdb command allows the user to drop a core file of the child
2880 process state at any time. So far it's been implemented only for
2881 GNU/Linux and Solaris, but should be relatively easily ported to other
2882 hosts. Argument is core file name (defaults to core.<pid>).
2884 * New command line option
2886 GDB now accepts --pid or -p followed by a process id.
2888 * Change in command line behavior -- corefiles vs. process ids.
2890 There is a subtle behavior in the way in which GDB handles
2891 command line arguments. The first non-flag argument is always
2892 a program to debug, but the second non-flag argument may either
2893 be a corefile or a process id. Previously, GDB would attempt to
2894 open the second argument as a corefile, and if that failed, would
2895 issue a superfluous error message and then attempt to attach it as
2896 a process. Now, if the second argument begins with a non-digit,
2897 it will be treated as a corefile. If it begins with a digit,
2898 GDB will attempt to attach it as a process, and if no such process
2899 is found, will then attempt to open it as a corefile.
2901 * Changes in ARM configurations.
2903 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2904 configuration is fully multi-arch.
2906 * New native configurations
2908 ARM NetBSD arm*-*-netbsd*
2909 x86 OpenBSD i[3456]86-*-openbsd*
2910 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2911 Sparc64 running FreeBSD sparc64-*-freebsd*
2915 Sanyo XStormy16 xstormy16-elf
2917 * OBSOLETE configurations and files
2919 Configurations that have been declared obsolete in this release have
2920 been commented out. Unless there is activity to revive these
2921 configurations, the next release of GDB will have their sources
2922 permanently REMOVED.
2924 AMD 29k family via UDI a29k-amd-udi, udi29k
2925 A29K VxWorks a29k-*-vxworks
2926 AMD 29000 embedded, using EBMON a29k-none-none
2927 AMD 29000 embedded with COFF a29k-none-coff
2928 AMD 29000 embedded with a.out a29k-none-aout
2930 testsuite/gdb.hp/gdb.threads-hp/ directory
2932 * REMOVED configurations and files
2934 TI TMS320C80 tic80-*-*
2936 PowerPC Solaris powerpcle-*-solaris*
2937 PowerPC Windows NT powerpcle-*-cygwin32
2938 PowerPC Netware powerpc-*-netware*
2939 Harris/CXUX m88k m88*-harris-cxux*
2940 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2941 ns32k-utek-sysv* ns32k-utek-*
2942 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2943 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2944 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2945 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2946 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2948 * Changes to command line processing
2950 The new `--args' feature can be used to specify command-line arguments
2951 for the inferior from gdb's command line.
2953 * Changes to key bindings
2955 There is a new `operate-and-get-next' function bound to `C-o'.
2957 *** Changes in GDB 5.1.1
2959 Fix compile problem on DJGPP.
2961 Fix a problem with floating-point registers on the i386 being
2964 Fix to stop GDB crashing on .debug_str debug info.
2966 Numerous documentation fixes.
2968 Numerous testsuite fixes.
2970 *** Changes in GDB 5.1:
2972 * New native configurations
2974 Alpha FreeBSD alpha*-*-freebsd*
2975 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2976 MIPS GNU/Linux mips*-*-linux*
2977 MIPS SGI Irix 6.x mips*-sgi-irix6*
2978 ia64 AIX ia64-*-aix*
2979 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2983 Motorola 68HC11 and 68HC12 m68hc11-elf
2985 UltraSparc running GNU/Linux sparc64-*-linux*
2987 * OBSOLETE configurations and files
2989 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2990 Harris/CXUX m88k m88*-harris-cxux*
2991 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2992 ns32k-utek-sysv* ns32k-utek-*
2993 TI TMS320C80 tic80-*-*
2995 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2996 PowerPC Solaris powerpcle-*-solaris*
2997 PowerPC Windows NT powerpcle-*-cygwin32
2998 PowerPC Netware powerpc-*-netware*
2999 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3000 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3001 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3002 Apple Macintosh (MPW) host N/A
3004 stuff.c (Program to stuff files into a specially prepared space in kdb)
3005 kdb-start.c (Main loop for the standalone kernel debugger)
3007 Configurations that have been declared obsolete in this release have
3008 been commented out. Unless there is activity to revive these
3009 configurations, the next release of GDB will have their sources
3010 permanently REMOVED.
3012 * REMOVED configurations and files
3014 Altos 3068 m68*-altos-*
3015 Convex c1-*-*, c2-*-*
3017 ARM RISCix arm-*-* (as host)
3021 * GDB has been converted to ISO C.
3023 GDB's source code has been converted to ISO C. In particular, the
3024 sources are fully protoized, and rely on standard headers being
3029 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3031 * The MI enabled by default.
3033 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3034 revised and enabled by default. Packages which use GDB as a debugging
3035 engine behind a UI or another front end are encouraged to switch to
3036 using the GDB/MI interface, instead of the old annotations interface
3037 which is now deprecated.
3039 * Support for debugging Pascal programs.
3041 GDB now includes support for debugging Pascal programs. The following
3042 main features are supported:
3044 - Pascal-specific data types such as sets;
3046 - automatic recognition of Pascal sources based on file-name
3049 - Pascal-style display of data types, variables, and functions;
3051 - a Pascal expression parser.
3053 However, some important features are not yet supported.
3055 - Pascal string operations are not supported at all;
3057 - there are some problems with boolean types;
3059 - Pascal type hexadecimal constants are not supported
3060 because they conflict with the internal variables format;
3062 - support for Pascal objects and classes is not full yet;
3064 - unlike Pascal, GDB is case-sensitive for symbol names.
3066 * Changes in completion.
3068 Commands such as `shell', `run' and `set args', which pass arguments
3069 to inferior programs, now complete on file names, similar to what
3070 users expect at the shell prompt.
3072 Commands which accept locations, such as `disassemble', `print',
3073 `breakpoint', `until', etc. now complete on filenames as well as
3074 program symbols. Thus, if you type "break foob TAB", and the source
3075 files linked into the programs include `foobar.c', that file name will
3076 be one of the candidates for completion. However, file names are not
3077 considered for completion after you typed a colon that delimits a file
3078 name from a name of a function in that file, as in "break foo.c:bar".
3080 `set demangle-style' completes on available demangling styles.
3082 * New platform-independent commands:
3084 It is now possible to define a post-hook for a command as well as a
3085 hook that runs before the command. For more details, see the
3086 documentation of `hookpost' in the GDB manual.
3088 * Changes in GNU/Linux native debugging.
3090 Support for debugging multi-threaded programs has been completely
3091 revised for all platforms except m68k and sparc. You can now debug as
3092 many threads as your system allows you to have.
3094 Attach/detach is supported for multi-threaded programs.
3096 Support for SSE registers was added for x86. This doesn't work for
3097 multi-threaded programs though.
3099 * Changes in MIPS configurations.
3101 Multi-arch support is enabled for all MIPS configurations.
3103 GDB can now be built as native debugger on SGI Irix 6.x systems for
3104 debugging n32 executables. (Debugging 64-bit executables is not yet
3107 * Unified support for hardware watchpoints in all x86 configurations.
3109 Most (if not all) native x86 configurations support hardware-assisted
3110 breakpoints and watchpoints in a unified manner. This support
3111 implements debug register sharing between watchpoints, which allows to
3112 put a virtually infinite number of watchpoints on the same address,
3113 and also supports watching regions up to 16 bytes with several debug
3116 The new maintenance command `maintenance show-debug-regs' toggles
3117 debugging print-outs in functions that insert, remove, and test
3118 watchpoints and hardware breakpoints.
3120 * Changes in the DJGPP native configuration.
3122 New command ``info dos sysinfo'' displays assorted information about
3123 the CPU, OS, memory, and DPMI server.
3125 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3126 display information about segment descriptors stored in GDT, LDT, and
3129 New commands ``info dos pde'' and ``info dos pte'' display entries
3130 from Page Directory and Page Tables (for now works with CWSDPMI only).
3131 New command ``info dos address-pte'' displays the Page Table entry for
3132 a given linear address.
3134 GDB can now pass command lines longer than 126 characters to the
3135 program being debugged (requires an update to the libdbg.a library
3136 which is part of the DJGPP development kit).
3138 DWARF2 debug info is now supported.
3140 It is now possible to `step' and `next' through calls to `longjmp'.
3142 * Changes in documentation.
3144 All GDB documentation was converted to GFDL, the GNU Free
3145 Documentation License.
3147 Tracepoints-related commands are now fully documented in the GDB
3150 TUI, the Text-mode User Interface, is now documented in the manual.
3152 Tracepoints-related commands are now fully documented in the GDB
3155 The "GDB Internals" manual now has an index. It also includes
3156 documentation of `ui_out' functions, GDB coding standards, x86
3157 hardware watchpoints, and memory region attributes.
3159 * GDB's version number moved to ``version.in''
3161 The Makefile variable VERSION has been replaced by the file
3162 ``version.in''. People creating GDB distributions should update the
3163 contents of this file.
3167 GUD support is now a standard part of the EMACS distribution.
3169 *** Changes in GDB 5.0:
3171 * Improved support for debugging FP programs on x86 targets
3173 Unified and much-improved support for debugging floating-point
3174 programs on all x86 targets. In particular, ``info float'' now
3175 displays the FP registers in the same format on all x86 targets, with
3176 greater level of detail.
3178 * Improvements and bugfixes in hardware-assisted watchpoints
3180 It is now possible to watch array elements, struct members, and
3181 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3182 on x86 targets no longer erroneously trigger when the address is
3185 * Improvements in the native DJGPP version of GDB
3187 The distribution now includes all the scripts and auxiliary files
3188 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3189 machines ``out of the box''.
3191 The DJGPP version can now debug programs that use signals. It is
3192 possible to catch signals that happened in the debuggee, deliver
3193 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3194 would kill the program being debugged.) Programs that hook hardware
3195 interrupts (keyboard, timer, etc.) can also be debugged.
3197 It is now possible to debug DJGPP programs that redirect their
3198 standard handles or switch them to raw (as opposed to cooked) mode, or
3199 even close them. The command ``run < foo > bar'' works as expected,
3200 and ``info terminal'' reports useful information about the debuggee's
3201 terminal, including raw/cooked mode, redirection, etc.
3203 The DJGPP version now uses termios functions for console I/O, which
3204 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3207 DOS-style file names with drive letters are now fully supported by
3210 It is now possible to debug DJGPP programs that switch their working
3211 directory. It is also possible to rerun the debuggee any number of
3212 times without restarting GDB; thus, you can use the same setup,
3213 breakpoints, etc. for many debugging sessions.
3215 * New native configurations
3217 ARM GNU/Linux arm*-*-linux*
3218 PowerPC GNU/Linux powerpc-*-linux*
3222 Motorola MCore mcore-*-*
3223 x86 VxWorks i[3456]86-*-vxworks*
3224 PowerPC VxWorks powerpc-*-vxworks*
3225 TI TMS320C80 tic80-*-*
3227 * OBSOLETE configurations
3229 Altos 3068 m68*-altos-*
3230 Convex c1-*-*, c2-*-*
3232 ARM RISCix arm-*-* (as host)
3235 Configurations that have been declared obsolete will be commented out,
3236 but the code will be left in place. If there is no activity to revive
3237 these configurations before the next release of GDB, the sources will
3238 be permanently REMOVED.
3240 * Gould support removed
3242 Support for the Gould PowerNode and NP1 has been removed.
3244 * New features for SVR4
3246 On SVR4 native platforms (such as Solaris), if you attach to a process
3247 without first loading a symbol file, GDB will now attempt to locate and
3248 load symbols from the running process's executable file.
3250 * Many C++ enhancements
3252 C++ support has been greatly improved. Overload resolution now works properly
3253 in almost all cases. RTTI support is on the way.
3255 * Remote targets can connect to a sub-program
3257 A popen(3) style serial-device has been added. This device starts a
3258 sub-process (such as a stand-alone simulator) and then communicates
3259 with that. The sub-program to run is specified using the syntax
3260 ``|<program> <args>'' vis:
3262 (gdb) set remotedebug 1
3263 (gdb) target extended-remote |mn10300-elf-sim program-args
3265 * MIPS 64 remote protocol
3267 A long standing bug in the mips64 remote protocol where by GDB
3268 expected certain 32 bit registers (ex SR) to be transfered as 32
3269 instead of 64 bits has been fixed.
3271 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3272 added to provide backward compatibility with older versions of GDB.
3274 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3276 The command ``set remotebinarydownload'' command has been replaced by
3277 ``set remote X-packet''. Other commands in ``set remote'' family
3278 include ``set remote P-packet''.
3280 * Breakpoint commands accept ranges.
3282 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3283 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3284 ``tracepoint passcount'' also accepts a range of tracepoints.
3286 * ``apropos'' command added.
3288 The ``apropos'' command searches through command names and
3289 documentation strings, printing out matches, making it much easier to
3290 try to find a command that does what you are looking for.
3294 A new machine oriented interface (MI) has been added to GDB. This
3295 interface is designed for debug environments running GDB as a separate
3296 process. This is part of the long term libGDB project. See the
3297 "GDB/MI" chapter of the GDB manual for further information. It can be
3298 enabled by configuring with:
3300 .../configure --enable-gdbmi
3302 *** Changes in GDB-4.18:
3304 * New native configurations
3306 HP-UX 10.20 hppa*-*-hpux10.20
3307 HP-UX 11.x hppa*-*-hpux11.0*
3308 M68K GNU/Linux m68*-*-linux*
3312 Fujitsu FR30 fr30-*-elf*
3313 Intel StrongARM strongarm-*-*
3314 Mitsubishi D30V d30v-*-*
3316 * OBSOLETE configurations
3318 Gould PowerNode, NP1 np1-*-*, pn-*-*
3320 Configurations that have been declared obsolete will be commented out,
3321 but the code will be left in place. If there is no activity to revive
3322 these configurations before the next release of GDB, the sources will
3323 be permanently REMOVED.
3327 As a compatibility experiment, GDB's source files buildsym.h and
3328 buildsym.c have been converted to pure standard C, no longer
3329 containing any K&R compatibility code. We believe that all systems in
3330 use today either come with a standard C compiler, or have a GCC port
3331 available. If this is not true, please report the affected
3332 configuration to bug-gdb@gnu.org immediately. See the README file for
3333 information about getting a standard C compiler if you don't have one
3338 GDB now uses readline 2.2.
3340 * set extension-language
3342 You can now control the mapping between filename extensions and source
3343 languages by using the `set extension-language' command. For instance,
3344 you can ask GDB to treat .c files as C++ by saying
3345 set extension-language .c c++
3346 The command `info extensions' lists all of the recognized extensions
3347 and their associated languages.
3349 * Setting processor type for PowerPC and RS/6000
3351 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3352 you can use the `set processor' command to specify what variant of the
3353 PowerPC family you are debugging. The command
3357 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3358 following PowerPC and RS6000 variants:
3360 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3361 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3363 403GC IBM PowerPC 403GC
3364 505 Motorola PowerPC 505
3365 860 Motorola PowerPC 860 or 850
3366 601 Motorola PowerPC 601
3367 602 Motorola PowerPC 602
3368 603 Motorola/IBM PowerPC 603 or 603e
3369 604 Motorola PowerPC 604 or 604e
3370 750 Motorola/IBM PowerPC 750 or 750
3372 At the moment, this command just tells GDB what to name the
3373 special-purpose processor registers. Since almost all the affected
3374 registers are inaccessible to user-level programs, this command is
3375 only useful for remote debugging in its present form.
3379 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3380 more extensive support for HP-UX. Added features include shared
3381 library support, kernel threads and hardware watchpoints for 11.00,
3382 support for HP's ANSI C and C++ compilers, and a compatibility mode
3383 for xdb and dbx commands.
3387 HP's donation includes the new concept of catchpoints, which is a
3388 generalization of the old catch command. On HP-UX, it is now possible
3389 to catch exec, fork, and vfork, as well as library loading.
3391 This means that the existing catch command has changed; its first
3392 argument now specifies the type of catch to be set up. See the
3393 output of "help catch" for a list of catchpoint types.
3395 * Debugging across forks
3397 On HP-UX, you can choose which process to debug when a fork() happens
3402 HP has donated a curses-based terminal user interface (TUI). To get
3403 it, build with --enable-tui. Although this can be enabled for any
3404 configuration, at present it only works for native HP debugging.
3406 * GDB remote protocol additions
3408 A new protocol packet 'X' that writes binary data is now available.
3409 Default behavior is to try 'X', then drop back to 'M' if the stub
3410 fails to respond. The settable variable `remotebinarydownload'
3411 allows explicit control over the use of 'X'.
3413 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3414 full 64-bit address. The command
3416 set remoteaddresssize 32
3418 can be used to revert to the old behaviour. For existing remote stubs
3419 the change should not be noticed, as the additional address information
3422 In order to assist in debugging stubs, you may use the maintenance
3423 command `packet' to send any text string to the stub. For instance,
3425 maint packet heythere
3427 sends the packet "$heythere#<checksum>". Note that it is very easy to
3428 disrupt a debugging session by sending the wrong packet at the wrong
3431 The compare-sections command allows you to compare section data on the
3432 target to what is in the executable file without uploading or
3433 downloading, by comparing CRC checksums.
3435 * Tracing can collect general expressions
3437 You may now collect general expressions at tracepoints. This requires
3438 further additions to the target-side stub; see tracepoint.c and
3439 doc/agentexpr.texi for further details.
3441 * mask-address variable for Mips
3443 For Mips targets, you may control the zeroing of the upper 32 bits of
3444 a 64-bit address by entering `set mask-address on'. This is mainly
3445 of interest to users of embedded R4xxx and R5xxx processors.
3447 * Higher serial baud rates
3449 GDB's serial code now allows you to specify baud rates 57600, 115200,
3450 230400, and 460800 baud. (Note that your host system may not be able
3451 to achieve all of these rates.)
3455 The i960 configuration now includes an initial implementation of a
3456 builtin simulator, contributed by Jim Wilson.
3459 *** Changes in GDB-4.17:
3461 * New native configurations
3463 Alpha GNU/Linux alpha*-*-linux*
3464 Unixware 2.x i[3456]86-unixware2*
3465 Irix 6.x mips*-sgi-irix6*
3466 PowerPC GNU/Linux powerpc-*-linux*
3467 PowerPC Solaris powerpcle-*-solaris*
3468 Sparc GNU/Linux sparc-*-linux*
3469 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3473 Argonaut Risc Chip (ARC) arc-*-*
3474 Hitachi H8/300S h8300*-*-*
3475 Matsushita MN10200 w/simulator mn10200-*-*
3476 Matsushita MN10300 w/simulator mn10300-*-*
3477 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3478 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3479 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3480 Mitsubishi D10V w/simulator d10v-*-*
3481 Mitsubishi M32R/D w/simulator m32r-*-elf*
3482 Tsqware Sparclet sparclet-*-*
3483 NEC V850 w/simulator v850-*-*
3485 * New debugging protocols
3487 ARM with RDI protocol arm*-*-*
3488 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3489 DDB and LSI variants of PMON protocol mips*-*-*
3490 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3491 PowerPC with SDS protocol powerpc{,le}-*-eabi
3492 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3496 All configurations can now understand and use the DWARF 2 debugging
3497 format. The choice is automatic, if the symbol file contains DWARF 2
3502 GDB now includes basic Java language support. This support is
3503 only useful with Java compilers that produce native machine code.
3505 * solib-absolute-prefix and solib-search-path
3507 For SunOS and SVR4 shared libraries, you may now set the prefix for
3508 loading absolute shared library symbol files, and the search path for
3509 locating non-absolute shared library symbol files.
3511 * Live range splitting
3513 GDB can now effectively debug code for which GCC has performed live
3514 range splitting as part of its optimization. See gdb/doc/LRS for
3515 more details on the expected format of the stabs information.
3519 GDB's support for the GNU Hurd, including thread debugging, has been
3520 updated to work with current versions of the Hurd.
3524 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3525 instruction set. ARM GDB automatically detects when Thumb
3526 instructions are in use, and adjusts disassembly and backtracing
3531 GDB's MIPS target configurations now handle the MIP16 16-bit
3536 GDB now includes support for overlays; if an executable has been
3537 linked such that multiple sections are based at the same address, GDB
3538 will decide which section to use for symbolic info. You can choose to
3539 control the decision manually, using overlay commands, or implement
3540 additional target-side support and use "overlay load-target" to bring
3541 in the overlay mapping. Do "help overlay" for more detail.
3545 The command "info symbol <address>" displays information about
3546 the symbol at the specified address.
3550 The standard remote protocol now includes an extension that allows
3551 asynchronous collection and display of trace data. This requires
3552 extensive support in the target-side debugging stub. Tracing mode
3553 includes a new interaction mode in GDB and new commands: see the
3554 file tracepoint.c for more details.
3558 Configurations for embedded MIPS now include a simulator contributed
3559 by Cygnus Solutions. The simulator supports the instruction sets
3560 of most MIPS variants.
3564 Sparc configurations may now include the ERC32 simulator contributed
3565 by the European Space Agency. The simulator is not built into
3566 Sparc targets by default; configure with --enable-sim to include it.
3570 For target configurations that may include multiple variants of a
3571 basic architecture (such as MIPS and SH), you may now set the
3572 architecture explicitly. "set arch" sets, "info arch" lists
3573 the possible architectures.
3575 *** Changes in GDB-4.16:
3577 * New native configurations
3579 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3580 M68K NetBSD m68k-*-netbsd*
3581 PowerPC AIX 4.x powerpc-*-aix*
3582 PowerPC MacOS powerpc-*-macos*
3583 PowerPC Windows NT powerpcle-*-cygwin32
3584 RS/6000 AIX 4.x rs6000-*-aix4*
3588 ARM with RDP protocol arm-*-*
3589 I960 with MON960 i960-*-coff
3590 MIPS VxWorks mips*-*-vxworks*
3591 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3592 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3594 Matra Sparclet sparclet-*-*
3598 The powerpc-eabi configuration now includes the PSIM simulator,
3599 contributed by Andrew Cagney, with assistance from Mike Meissner.
3600 PSIM is a very elaborate model of the PowerPC, including not only
3601 basic instruction set execution, but also details of execution unit
3602 performance and I/O hardware. See sim/ppc/README for more details.
3606 GDB now works with Solaris 2.5.
3608 * Windows 95/NT native
3610 GDB will now work as a native debugger on Windows 95 and Windows NT.
3611 To build it from source, you must use the "gnu-win32" environment,
3612 which uses a DLL to emulate enough of Unix to run the GNU tools.
3613 Further information, binaries, and sources are available at
3614 ftp.cygnus.com, under pub/gnu-win32.
3616 * dont-repeat command
3618 If a user-defined command includes the command `dont-repeat', then the
3619 command will not be repeated if the user just types return. This is
3620 useful if the command is time-consuming to run, so that accidental
3621 extra keystrokes don't run the same command many times.
3623 * Send break instead of ^C
3625 The standard remote protocol now includes an option to send a break
3626 rather than a ^C to the target in order to interrupt it. By default,
3627 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3629 * Remote protocol timeout
3631 The standard remote protocol includes a new variable `remotetimeout'
3632 that allows you to set the number of seconds before GDB gives up trying
3633 to read from the target. The default value is 2.
3635 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3637 By default GDB will automatically keep track of objects as they are
3638 loaded and unloaded by the dynamic linker. By using the command `set
3639 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3640 when shared library events occur, thus allowing you to set breakpoints
3641 in shared libraries which are explicitly loaded by the inferior.
3643 Note this feature does not work on hpux8. On hpux9 you must link
3644 /usr/lib/end.o into your program. This feature should work
3645 automatically on hpux10.
3647 * Irix 5.x hardware watchpoint support
3649 Irix 5 configurations now support the use of hardware watchpoints.
3651 * Mips protocol "SYN garbage limit"
3653 When debugging a Mips target using the `target mips' protocol, you
3654 may set the number of characters that GDB will ignore by setting
3655 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3656 every character. The default value is 1050.
3658 * Recording and replaying remote debug sessions
3660 If you set `remotelogfile' to the name of a file, gdb will write to it
3661 a recording of a remote debug session. This recording may then be
3662 replayed back to gdb using "gdbreplay". See gdbserver/README for
3663 details. This is useful when you have a problem with GDB while doing
3664 remote debugging; you can make a recording of the session and send it
3665 to someone else, who can then recreate the problem.
3667 * Speedups for remote debugging
3669 GDB includes speedups for downloading and stepping MIPS systems using
3670 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3671 and more efficient S-record downloading.
3673 * Memory use reductions and statistics collection
3675 GDB now uses less memory and reports statistics about memory usage.
3676 Try the `maint print statistics' command, for example.
3678 *** Changes in GDB-4.15:
3680 * Psymtabs for XCOFF
3682 The symbol reader for AIX GDB now uses partial symbol tables. This
3683 can greatly improve startup time, especially for large executables.
3685 * Remote targets use caching
3687 Remote targets now use a data cache to speed up communication with the
3688 remote side. The data cache could lead to incorrect results because
3689 it doesn't know about volatile variables, thus making it impossible to
3690 debug targets which use memory mapped I/O devices. `set remotecache
3691 off' turns the the data cache off.
3693 * Remote targets may have threads
3695 The standard remote protocol now includes support for multiple threads
3696 in the target system, using new protocol commands 'H' and 'T'. See
3697 gdb/remote.c for details.
3701 If GDB is configured with `--enable-netrom', then it will include
3702 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3703 acts as though it is a bank of ROM on the target board, but you can
3704 write into it over the network. GDB's support consists only of
3705 support for fast loading into the emulated ROM; to debug, you must use
3706 another protocol, such as standard remote protocol. The usual
3707 sequence is something like
3709 target nrom <netrom-hostname>
3711 target remote <netrom-hostname>:1235
3715 GDB now includes support for the Apple Macintosh, as a host only. It
3716 may be run as either an MPW tool or as a standalone application, and
3717 it can debug through the serial port. All the usual GDB commands are
3718 available, but to the target command, you must supply "serial" as the
3719 device type instead of "/dev/ttyXX". See mpw-README in the main
3720 directory for more information on how to build. The MPW configuration
3721 scripts */mpw-config.in support only a few targets, and only the
3722 mips-idt-ecoff target has been tested.
3726 GDB configuration now uses autoconf. This is not user-visible,
3727 but does simplify configuration and building.
3731 GDB now supports hpux10.
3733 *** Changes in GDB-4.14:
3735 * New native configurations
3737 x86 FreeBSD i[345]86-*-freebsd
3738 x86 NetBSD i[345]86-*-netbsd
3739 NS32k NetBSD ns32k-*-netbsd
3740 Sparc NetBSD sparc-*-netbsd
3744 A29K VxWorks a29k-*-vxworks
3745 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3746 CPU32 EST-300 emulator m68*-*-est*
3747 PowerPC ELF powerpc-*-elf
3750 * Alpha OSF/1 support for procfs
3752 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3753 possible to attach to running processes. As the mounting of the /proc
3754 filesystem is optional on the Alpha, GDB automatically determines
3755 the availability of /proc during startup. This can lead to problems
3756 if /proc is unmounted after GDB has been started.
3758 * Arguments to user-defined commands
3760 User commands may accept up to 10 arguments separated by whitespace.
3761 Arguments are accessed within the user command via $arg0..$arg9. A
3764 print $arg0 + $arg1 + $arg2
3766 To execute the command use:
3769 Defines the command "adder" which prints the sum of its three arguments.
3770 Note the arguments are text substitutions, so they may reference variables,
3771 use complex expressions, or even perform inferior function calls.
3773 * New `if' and `while' commands
3775 This makes it possible to write more sophisticated user-defined
3776 commands. Both commands take a single argument, which is the
3777 expression to evaluate, and must be followed by the commands to
3778 execute, one per line, if the expression is nonzero, the list being
3779 terminated by the word `end'. The `if' command list may include an
3780 `else' word, which causes the following commands to be executed only
3781 if the expression is zero.
3783 * Fortran source language mode
3785 GDB now includes partial support for Fortran 77. It will recognize
3786 Fortran programs and can evaluate a subset of Fortran expressions, but
3787 variables and functions may not be handled correctly. GDB will work
3788 with G77, but does not yet know much about symbols emitted by other
3791 * Better HPUX support
3793 Most debugging facilities now work on dynamic executables for HPPAs
3794 running hpux9 or later. You can attach to running dynamically linked
3795 processes, but by default the dynamic libraries will be read-only, so
3796 for instance you won't be able to put breakpoints in them. To change
3797 that behavior do the following before running the program:
3803 This will cause the libraries to be mapped private and read-write.
3804 To revert to the normal behavior, do this:
3810 You cannot set breakpoints or examine data in the library until after
3811 the library is loaded if the function/data symbols do not have
3814 GDB can now also read debug symbols produced by the HP C compiler on
3815 HPPAs (sorry, no C++, Fortran or 68k support).
3817 * Target byte order now dynamically selectable
3819 You can choose which byte order to use with a target system, via the
3820 commands "set endian big" and "set endian little", and you can see the
3821 current setting by using "show endian". You can also give the command
3822 "set endian auto", in which case GDB will use the byte order
3823 associated with the executable. Currently, only embedded MIPS
3824 configurations support dynamic selection of target byte order.
3826 * New DOS host serial code
3828 This version uses DPMI interrupts to handle buffered I/O, so you
3829 no longer need to run asynctsr when debugging boards connected to
3832 *** Changes in GDB-4.13:
3834 * New "complete" command
3836 This lists all the possible completions for the rest of the line, if it
3837 were to be given as a command itself. This is intended for use by emacs.
3839 * Trailing space optional in prompt
3841 "set prompt" no longer adds a space for you after the prompt you set. This
3842 allows you to set a prompt which ends in a space or one that does not.
3844 * Breakpoint hit counts
3846 "info break" now displays a count of the number of times the breakpoint
3847 has been hit. This is especially useful in conjunction with "ignore"; you
3848 can ignore a large number of breakpoint hits, look at the breakpoint info
3849 to see how many times the breakpoint was hit, then run again, ignoring one
3850 less than that number, and this will get you quickly to the last hit of
3853 * Ability to stop printing at NULL character
3855 "set print null-stop" will cause GDB to stop printing the characters of
3856 an array when the first NULL is encountered. This is useful when large
3857 arrays actually contain only short strings.
3859 * Shared library breakpoints
3861 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3862 breakpoints in shared libraries before the executable is run.
3864 * Hardware watchpoints
3866 There is a new hardware breakpoint for the watch command for sparclite
3867 targets. See gdb/sparclite/hw_breakpoint.note.
3869 Hardware watchpoints are also now supported under GNU/Linux.
3873 Annotations have been added. These are for use with graphical interfaces,
3874 and are still experimental. Currently only gdba.el uses these.
3876 * Improved Irix 5 support
3878 GDB now works properly with Irix 5.2.
3880 * Improved HPPA support
3882 GDB now works properly with the latest GCC and GAS.
3884 * New native configurations
3886 Sequent PTX4 i[34]86-sequent-ptx4
3887 HPPA running OSF/1 hppa*-*-osf*
3888 Atari TT running SVR4 m68*-*-sysv4*
3889 RS/6000 LynxOS rs6000-*-lynxos*
3893 OS/9000 i[34]86-*-os9k
3894 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3897 * Hitachi SH7000 and E7000-PC ICE support
3899 There is now support for communicating with the Hitachi E7000-PC ICE.
3900 This is available automatically when GDB is configured for the SH.
3904 As usual, a variety of small fixes and improvements, both generic
3905 and configuration-specific. See the ChangeLog for more detail.
3907 *** Changes in GDB-4.12:
3909 * Irix 5 is now supported
3913 GDB-4.12 on the HPPA has a number of changes which make it unable
3914 to debug the output from the currently released versions of GCC and
3915 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3916 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3917 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3920 *** Changes in GDB-4.11:
3922 * User visible changes:
3926 The "set remotedebug" option is now consistent between the mips remote
3927 target, remote targets using the gdb-specific protocol, UDI (AMD's
3928 debug protocol for the 29k) and the 88k bug monitor. It is now an
3929 integer specifying a debug level (normally 0 or 1, but 2 means more
3930 debugging info for the mips target).
3932 * DEC Alpha native support
3934 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3935 debug info, but GDB works fairly well with the DEC compiler and should
3936 work with a future GCC release. See the README file for a few
3937 Alpha-specific notes.
3939 * Preliminary thread implementation
3941 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3943 * LynxOS native and target support for 386
3945 This release has been hosted on LynxOS 2.2, and also can be configured
3946 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3949 * Improvements in C++ mangling/demangling.
3951 This release has much better g++ debugging, specifically in name
3952 mangling/demangling, virtual function calls, print virtual table,
3953 call methods, ...etc.
3955 *** Changes in GDB-4.10:
3957 * User visible changes:
3959 Remote debugging using the GDB-specific (`target remote') protocol now
3960 supports the `load' command. This is only useful if you have some
3961 other way of getting the stub to the target system, and you can put it
3962 somewhere in memory where it won't get clobbered by the download.
3964 Filename completion now works.
3966 When run under emacs mode, the "info line" command now causes the
3967 arrow to point to the line specified. Also, "info line" prints
3968 addresses in symbolic form (as well as hex).
3970 All vxworks based targets now support a user settable option, called
3971 vxworks-timeout. This option represents the number of seconds gdb
3972 should wait for responses to rpc's. You might want to use this if
3973 your vxworks target is, perhaps, a slow software simulator or happens
3974 to be on the far side of a thin network line.
3978 This release contains support for using a DEC alpha as a GDB host for
3979 cross debugging. Native alpha debugging is not supported yet.
3982 *** Changes in GDB-4.9:
3986 This is the first GDB release which is accompanied by a matching testsuite.
3987 The testsuite requires installation of dejagnu, which should be available
3988 via ftp from most sites that carry GNU software.
3992 'Cfront' style demangling has had its name changed to 'ARM' style, to
3993 emphasize that it was written from the specifications in the C++ Annotated
3994 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3995 disclaimers, it still generated too much confusion with users attempting to
3996 use gdb with AT&T cfront.
4000 GDB now uses a standard remote interface to a simulator library.
4001 So far, the library contains simulators for the Zilog Z8001/2, the
4002 Hitachi H8/300, H8/500 and Super-H.
4004 * New targets supported
4006 H8/300 simulator h8300-hitachi-hms or h8300hms
4007 H8/500 simulator h8500-hitachi-hms or h8500hms
4008 SH simulator sh-hitachi-hms or sh
4009 Z8000 simulator z8k-zilog-none or z8ksim
4010 IDT MIPS board over serial line mips-idt-ecoff
4012 Cross-debugging to GO32 targets is supported. It requires a custom
4013 version of the i386-stub.c module which is integrated with the
4014 GO32 memory extender.
4016 * New remote protocols
4018 MIPS remote debugging protocol.
4020 * New source languages supported
4022 This version includes preliminary support for Chill, a Pascal like language
4023 used by telecommunications companies. Chill support is also being integrated
4024 into the GNU compiler, but we don't know when it will be publically available.
4027 *** Changes in GDB-4.8:
4029 * HP Precision Architecture supported
4031 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4032 version of this support was available as a set of patches from the
4033 University of Utah. GDB does not support debugging of programs
4034 compiled with the HP compiler, because HP will not document their file
4035 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4036 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4038 Many problems in the preliminary version have been fixed.
4040 * Faster and better demangling
4042 We have improved template demangling and fixed numerous bugs in the GNU style
4043 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4044 character types (wchar_t) are now supported. Demangling of each symbol is now
4045 only done once, and is cached when the symbol table for a file is read in.
4046 This results in a small increase in memory usage for C programs, a moderate
4047 increase in memory usage for C++ programs, and a fantastic speedup in
4050 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4051 from the specifications in the Annotated Reference Manual, which AT&T's
4052 compiler does not actually implement.
4054 * G++ multiple inheritance compiler problem
4056 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4057 inheritance lattices was reworked to properly discover ambiguities. We
4058 recently found an example which causes this new algorithm to fail in a
4059 very subtle way, producing bad debug information for those classes.
4060 The file 'gcc.patch' (in this directory) can be applied to gcc to
4061 circumvent the problem. A future GCC release will contain a complete
4064 The previous G++ debug info problem (mentioned below for the gdb-4.7
4065 release) is fixed in gcc version 2.3.2.
4067 * Improved configure script
4069 The `configure' script will now attempt to guess your system type if
4070 you don't supply a host system type. The old scheme of supplying a
4071 host system triplet is preferable over using this. All the magic is
4072 done in the new `config.guess' script. Examine it for details.
4074 We have also brought our configure script much more in line with the FSF's
4075 version. It now supports the --with-xxx options. In particular,
4076 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4077 The resulting GDB will not be able to read arbitrary object file formats --
4078 only the format ``expected'' to be used on the configured target system.
4079 We hope to make this the default in a future release.
4081 * Documentation improvements
4083 There's new internal documentation on how to modify GDB, and how to
4084 produce clean changes to the code. We implore people to read it
4085 before submitting changes.
4087 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4088 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4089 `info' files are also provided. To build `info' files from scratch,
4090 you will need the latest `makeinfo' release, which will be available in
4091 a future texinfo-X.Y release.
4093 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4094 We're not sure exactly which versions have this problem, but it has
4095 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4096 or better. If that isn't possible, there is a patch in
4097 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4098 around this problem.
4102 GDB now supports array constants that can be used in expressions typed in by
4103 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4104 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4107 The new directory `gdb/sparclite' contains a program that demonstrates
4108 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4110 * New native hosts supported
4112 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4113 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4115 * New targets supported
4117 AMD 29k family via UDI a29k-amd-udi or udi29k
4119 * New file formats supported
4121 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4122 HPUX core files, and SCO 3.2v2 core files.
4126 Attaching to processes now works again; thanks for the many bug reports.
4128 We have also stomped on a bunch of core dumps caused by
4129 printf_filtered("%s") problems.
4131 We eliminated a copyright problem on the rpc and ptrace header files
4132 for VxWorks, which was discovered at the last minute during the 4.7
4133 release. You should now be able to build a VxWorks GDB.
4135 You can now interrupt gdb while an attached process is running. This
4136 will cause the attached process to stop, and give control back to GDB.
4138 We fixed problems caused by using too many file descriptors
4139 for reading symbols from object files and libraries. This was
4140 especially a problem for programs that used many (~100) shared
4143 The `step' command now only enters a subroutine if there is line number
4144 information for the subroutine. Otherwise it acts like the `next'
4145 command. Previously, `step' would enter subroutines if there was
4146 any debugging information about the routine. This avoids problems
4147 when using `cc -g1' on MIPS machines.
4149 * Internal improvements
4151 GDB's internal interfaces have been improved to make it easier to support
4152 debugging of multiple languages in the future.
4154 GDB now uses a common structure for symbol information internally.
4155 Minimal symbols (derived from linkage symbols in object files), partial
4156 symbols (from a quick scan of debug information), and full symbols
4157 contain a common subset of information, making it easier to write
4158 shared code that handles any of them.
4160 * New command line options
4162 We now accept --silent as an alias for --quiet.
4166 The memory-mapped-malloc library is now licensed under the GNU Library
4167 General Public License.
4169 *** Changes in GDB-4.7:
4171 * Host/native/target split
4173 GDB has had some major internal surgery to untangle the support for
4174 hosts and remote targets. Now, when you configure GDB for a remote
4175 target, it will no longer load in all of the support for debugging
4176 local programs on the host. When fully completed and tested, this will
4177 ensure that arbitrary host/target combinations are possible.
4179 The primary conceptual shift is to separate the non-portable code in
4180 GDB into three categories. Host specific code is required any time GDB
4181 is compiled on that host, regardless of the target. Target specific
4182 code relates to the peculiarities of the target, but can be compiled on
4183 any host. Native specific code is everything else: it can only be
4184 built when the host and target are the same system. Child process
4185 handling and core file support are two common `native' examples.
4187 GDB's use of /proc for controlling Unix child processes is now cleaner.
4188 It has been split out into a single module under the `target_ops' vector,
4189 plus two native-dependent functions for each system that uses /proc.
4191 * New hosts supported
4193 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4194 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4195 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4197 * New targets supported
4199 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4200 68030 and CPU32 m68030-*-*, m68332-*-*
4202 * New native hosts supported
4204 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4205 (386bsd is not well tested yet)
4206 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4208 * New file formats supported
4210 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4211 supports reading of `a.out.adobe' object files, which are an a.out
4212 format extended with minimal information about multiple sections.
4216 `show copying' is the same as the old `info copying'.
4217 `show warranty' is the same as `info warrantee'.
4218 These were renamed for consistency. The old commands continue to work.
4220 `info handle' is a new alias for `info signals'.
4222 You can now define pre-command hooks, which attach arbitrary command
4223 scripts to any command. The commands in the hook will be executed
4224 prior to the user's command. You can also create a hook which will be
4225 executed whenever the program stops. See gdb.texinfo.
4229 We now deal with Cfront style name mangling, and can even extract type
4230 info from mangled symbols. GDB can automatically figure out which
4231 symbol mangling style your C++ compiler uses.
4233 Calling of methods and virtual functions has been improved as well.
4237 The crash that occured when debugging Sun Ansi-C compiled binaries is
4238 fixed. This was due to mishandling of the extra N_SO stabs output
4241 We also finally got Ultrix 4.2 running in house, and fixed core file
4242 support, with help from a dozen people on the net.
4244 John M. Farrell discovered that the reason that single-stepping was so
4245 slow on all of the Mips based platforms (primarily SGI and DEC) was
4246 that we were trying to demangle and lookup a symbol used for internal
4247 purposes on every instruction that was being stepped through. Changing
4248 the name of that symbol so that it couldn't be mistaken for a C++
4249 mangled symbol sped things up a great deal.
4251 Rich Pixley sped up symbol lookups in general by getting much smarter
4252 about when C++ symbol mangling is necessary. This should make symbol
4253 completion (TAB on the command line) much faster. It's not as fast as
4254 we'd like, but it's significantly faster than gdb-4.6.
4258 A new user controllable variable 'call_scratch_address' can
4259 specify the location of a scratch area to be used when GDB
4260 calls a function in the target. This is necessary because the
4261 usual method of putting the scratch area on the stack does not work
4262 in systems that have separate instruction and data spaces.
4264 We integrated changes to support the 29k UDI (Universal Debugger
4265 Interface), but discovered at the last minute that we didn't have all
4266 of the appropriate copyright paperwork. We are working with AMD to
4267 resolve this, and hope to have it available soon.
4271 We have sped up the remote serial line protocol, especially for targets
4272 with lots of registers. It now supports a new `expedited status' ('T')
4273 message which can be used in place of the existing 'S' status message.
4274 This allows the remote stub to send only the registers that GDB
4275 needs to make a quick decision about single-stepping or conditional
4276 breakpoints, eliminating the need to fetch the entire register set for
4277 each instruction being stepped through.
4279 The GDB remote serial protocol now implements a write-through cache for
4280 registers, only re-reading the registers if the target has run.
4282 There is also a new remote serial stub for SPARC processors. You can
4283 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4284 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4285 processor with a serial port.
4289 Configure.in files have become much easier to read and modify. A new
4290 `table driven' format makes it more obvious what configurations are
4291 supported, and what files each one uses.
4295 There is a new opcodes library which will eventually contain all of the
4296 disassembly routines and opcode tables. At present, it only contains
4297 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4298 disassembler (binutils/objdump) to share these routines.
4300 The libiberty library is now copylefted under the GNU Library General
4301 Public License. This allows more liberal use, and was done so libg++
4302 can use it. This makes no difference to GDB, since the Library License
4303 grants all the rights from the General Public License.
4307 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4308 reference to the stabs symbol info used by the debugger. It is (as far
4309 as we know) the only published document on this fascinating topic. We
4310 encourage you to read it, compare it to the stabs information on your
4311 system, and send improvements on the document in general (to
4312 bug-gdb@prep.ai.mit.edu).
4314 And, of course, many bugs have been fixed.
4317 *** Changes in GDB-4.6:
4319 * Better support for C++ function names
4321 GDB now accepts as input the "demangled form" of C++ overloaded function
4322 names and member function names, and can do command completion on such names
4323 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4324 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4325 Make use of command completion, it is your friend.
4327 GDB also now accepts a variety of C++ mangled symbol formats. They are
4328 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4329 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4330 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4331 for the list of formats.
4333 * G++ symbol mangling problem
4335 Recent versions of gcc have a bug in how they emit debugging information for
4336 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4337 directory) can be applied to gcc to fix the problem. Alternatively, if you
4338 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4339 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4340 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4343 * New 'maintenance' command
4345 All of the commands related to hacking GDB internals have been moved out of
4346 the main command set, and now live behind the 'maintenance' command. This
4347 can also be abbreviated as 'mt'. The following changes were made:
4349 dump-me -> maintenance dump-me
4350 info all-breakpoints -> maintenance info breakpoints
4351 printmsyms -> maintenance print msyms
4352 printobjfiles -> maintenance print objfiles
4353 printpsyms -> maintenance print psymbols
4354 printsyms -> maintenance print symbols
4356 The following commands are new:
4358 maintenance demangle Call internal GDB demangler routine to
4359 demangle a C++ link name and prints the result.
4360 maintenance print type Print a type chain for a given symbol
4362 * Change to .gdbinit file processing
4364 We now read the $HOME/.gdbinit file before processing the argv arguments
4365 (e.g. reading symbol files or core files). This allows global parameters to
4366 be set, which will apply during the symbol reading. The ./.gdbinit is still
4367 read after argv processing.
4369 * New hosts supported
4371 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4373 GNU/Linux support i386-unknown-linux or linux
4375 We are also including code to support the HP/PA running BSD and HPUX. This
4376 is almost guaranteed not to work, as we didn't have time to test or build it
4377 for this release. We are including it so that the more adventurous (or
4378 masochistic) of you can play with it. We also had major problems with the
4379 fact that the compiler that we got from HP doesn't support the -g option.
4382 * New targets supported
4384 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4386 * More smarts about finding #include files
4388 GDB now remembers the compilation directory for all include files, and for
4389 all files from which C is generated (like yacc and lex sources). This
4390 greatly improves GDB's ability to find yacc/lex sources, and include files,
4391 especially if you are debugging your program from a directory different from
4392 the one that contains your sources.
4394 We also fixed a bug which caused difficulty with listing and setting
4395 breakpoints in include files which contain C code. (In the past, you had to
4396 try twice in order to list an include file that you hadn't looked at before.)
4398 * Interesting infernals change
4400 GDB now deals with arbitrary numbers of sections, where the symbols for each
4401 section must be relocated relative to that section's landing place in the
4402 target's address space. This work was needed to support ELF with embedded
4403 stabs used by Solaris-2.0.
4405 * Bug fixes (of course!)
4407 There have been loads of fixes for the following things:
4408 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4409 i960, stabs, DOS(GO32), procfs, etc...
4411 See the ChangeLog for details.
4413 *** Changes in GDB-4.5:
4415 * New machines supported (host and target)
4417 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4419 SGI Irix-4.x mips-sgi-irix4 or iris4
4421 * New malloc package
4423 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4424 Mmalloc is capable of handling mutiple heaps of memory. It is also
4425 capable of saving a heap to a file, and then mapping it back in later.
4426 This can be used to greatly speedup the startup of GDB by using a
4427 pre-parsed symbol table which lives in a mmalloc managed heap. For
4428 more details, please read mmalloc/mmalloc.texi.
4432 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4433 'help info proc' for details.
4435 * MIPS ecoff symbol table format
4437 The code that reads MIPS symbol table format is now supported on all hosts.
4438 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4441 * File name changes for MS-DOS
4443 Many files in the config directories have been renamed to make it easier to
4444 support GDB on MS-DOSe systems (which have very restrictive file name
4445 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4446 environment) is close to working but has some remaining problems. Note
4447 that debugging of DOS programs is not supported, due to limitations
4448 in the ``operating system'', but it can be used to host cross-debugging.
4450 * Cross byte order fixes
4452 Many fixes have been made to support cross debugging of Sparc and MIPS
4453 targets from hosts whose byte order differs.
4455 * New -mapped and -readnow options
4457 If memory-mapped files are available on your system through the 'mmap'
4458 system call, you can use the -mapped option on the `file' or
4459 `symbol-file' commands to cause GDB to write the symbols from your
4460 program into a reusable file. If the program you are debugging is
4461 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4462 Future GDB debugging sessions will notice the presence of this file,
4463 and will quickly map in symbol information from it, rather than reading
4464 the symbol table from the executable program. Using the '-mapped'
4465 option in a GDB `file' or `symbol-file' command has the same effect as
4466 starting GDB with the '-mapped' command-line option.
4468 You can cause GDB to read the entire symbol table immediately by using
4469 the '-readnow' option with any of the commands that load symbol table
4470 information (or on the GDB command line). This makes the command
4471 slower, but makes future operations faster.
4473 The -mapped and -readnow options are typically combined in order to
4474 build a `fred.syms' file that contains complete symbol information.
4475 A simple GDB invocation to do nothing but build a `.syms' file for future
4478 gdb -batch -nx -mapped -readnow programname
4480 The `.syms' file is specific to the host machine on which GDB is run.
4481 It holds an exact image of GDB's internal symbol table. It cannot be
4482 shared across multiple host platforms.
4484 * longjmp() handling
4486 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4487 siglongjmp() without losing control. This feature has not yet been ported to
4488 all systems. It currently works on many 386 platforms, all MIPS-based
4489 platforms (SGI, DECstation, etc), and Sun3/4.
4493 Preliminary work has been put in to support the new Solaris OS from Sun. At
4494 this time, it can control and debug processes, but it is not capable of
4499 As always, many many bug fixes. The major areas were with g++, and mipsread.
4500 People using the MIPS-based platforms should experience fewer mysterious
4501 crashes and trashed symbol tables.
4503 *** Changes in GDB-4.4:
4505 * New machines supported (host and target)
4507 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4509 BSD Reno on Vax vax-dec-bsd
4510 Ultrix on Vax vax-dec-ultrix
4512 * New machines supported (target)
4514 AMD 29000 embedded, using EBMON a29k-none-none
4518 GDB continues to improve its handling of C++. `References' work better.
4519 The demangler has also been improved, and now deals with symbols mangled as
4520 per the Annotated C++ Reference Guide.
4522 GDB also now handles `stabs' symbol information embedded in MIPS
4523 `ecoff' symbol tables. Since the ecoff format was not easily
4524 extensible to handle new languages such as C++, this appeared to be a
4525 good way to put C++ debugging info into MIPS binaries. This option
4526 will be supported in the GNU C compiler, version 2, when it is
4529 * New features for SVR4
4531 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4532 shared libraries. Debugging dynamically linked programs should present
4533 only minor differences from debugging statically linked programs.
4535 The `info proc' command will print out information about any process
4536 on an SVR4 system (including the one you are debugging). At the moment,
4537 it prints the address mappings of the process.
4539 If you bring up GDB on another SVR4 system, please send mail to
4540 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4542 * Better dynamic linking support in SunOS
4544 Reading symbols from shared libraries which contain debugging symbols
4545 now works properly. However, there remain issues such as automatic
4546 skipping of `transfer vector' code during function calls, which
4547 make it harder to debug code in a shared library, than to debug the
4548 same code linked statically.
4552 GDB is now using the latest `getopt' routines from the FSF. This
4553 version accepts the -- prefix for options with long names. GDB will
4554 continue to accept the old forms (-option and +option) as well.
4555 Various single letter abbreviations for options have been explicity
4556 added to the option table so that they won't get overshadowed in the
4557 future by other options that begin with the same letter.
4561 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4562 Many assorted bugs have been handled. Many more remain to be handled.
4563 See the various ChangeLog files (primarily in gdb and bfd) for details.
4566 *** Changes in GDB-4.3:
4568 * New machines supported (host and target)
4570 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4571 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4572 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4574 * Almost SCO Unix support
4576 We had hoped to support:
4577 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4578 (except for core file support), but we discovered very late in the release
4579 that it has problems with process groups that render gdb unusable. Sorry
4580 about that. I encourage people to fix it and post the fixes.
4582 * Preliminary ELF and DWARF support
4584 GDB can read ELF object files on System V Release 4, and can handle
4585 debugging records for C, in DWARF format, in ELF files. This support
4586 is preliminary. If you bring up GDB on another SVR4 system, please
4587 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4592 GDB now uses the latest `readline' library. One user-visible change
4593 is that two tabs will list possible command completions, which previously
4594 required typing M-? (meta-question mark, or ESC ?).
4598 The `stepi' bug that many of you noticed has been squashed.
4599 Many bugs in C++ have been handled. Many more remain to be handled.
4600 See the various ChangeLog files (primarily in gdb and bfd) for details.
4602 * State of the MIPS world (in case you wondered):
4604 GDB can understand the symbol tables emitted by the compilers
4605 supplied by most vendors of MIPS-based machines, including DEC. These
4606 symbol tables are in a format that essentially nobody else uses.
4608 Some versions of gcc come with an assembler post-processor called
4609 mips-tfile. This program is required if you want to do source-level
4610 debugging of gcc-compiled programs. I believe FSF does not ship
4611 mips-tfile with gcc version 1, but it will eventually come with gcc
4614 Debugging of g++ output remains a problem. g++ version 1.xx does not
4615 really support it at all. (If you're lucky, you should be able to get
4616 line numbers and stack traces to work, but no parameters or local
4617 variables.) With some work it should be possible to improve the
4620 When gcc version 2 is released, you will have somewhat better luck.
4621 However, even then you will get confusing results for inheritance and
4624 We will eventually provide full debugging of g++ output on
4625 DECstations. This will probably involve some kind of stabs-in-ecoff
4626 encapulation, but the details have not been worked out yet.
4629 *** Changes in GDB-4.2:
4631 * Improved configuration
4633 Only one copy of `configure' exists now, and it is not self-modifying.
4634 Porting BFD is simpler.
4638 The `step' and `next' commands now only stop at the first instruction
4639 of a source line. This prevents the multiple stops that used to occur
4640 in switch statements, for-loops, etc. `Step' continues to stop if a
4641 function that has debugging information is called within the line.
4645 Lots of small bugs fixed. More remain.
4647 * New host supported (not target)
4649 Intel 386 PC clone running Mach i386-none-mach
4652 *** Changes in GDB-4.1:
4654 * Multiple source language support
4656 GDB now has internal scaffolding to handle several source languages.
4657 It determines the type of each source file from its filename extension,
4658 and will switch expression parsing and number formatting to match the
4659 language of the function in the currently selected stack frame.
4660 You can also specifically set the language to be used, with
4661 `set language c' or `set language modula-2'.
4665 GDB now has preliminary support for the GNU Modula-2 compiler,
4666 currently under development at the State University of New York at
4667 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4668 continue through the fall of 1991 and into 1992.
4670 Other Modula-2 compilers are currently not supported, and attempting to
4671 debug programs compiled with them will likely result in an error as the
4672 symbol table is read. Feel free to work on it, though!
4674 There are hooks in GDB for strict type checking and range checking,
4675 in the `Modula-2 philosophy', but they do not currently work.
4679 GDB can now write to executable and core files (e.g. patch
4680 a variable's value). You must turn this switch on, specify
4681 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4682 by assigning a new value to a variable. Modifications take
4685 * Automatic SunOS shared library reading
4687 When you run your program, GDB automatically determines where its
4688 shared libraries (if any) have been loaded, and reads their symbols.
4689 The `share' command is no longer needed. This also works when
4690 examining core files.
4694 You can specify the number of lines that the `list' command shows.
4697 * New machines supported (host and target)
4699 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4700 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4701 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4703 * New hosts supported (not targets)
4705 IBM RT/PC: romp-ibm-aix or rtpc
4707 * New targets supported (not hosts)
4709 AMD 29000 embedded with COFF a29k-none-coff
4710 AMD 29000 embedded with a.out a29k-none-aout
4711 Ultracomputer remote kernel debug a29k-nyu-kern
4713 * New remote interfaces
4719 *** Changes in GDB-4.0:
4723 Wide output is wrapped at good places to make the output more readable.
4725 Gdb now supports cross-debugging from a host machine of one type to a
4726 target machine of another type. Communication with the target system
4727 is over serial lines. The ``target'' command handles connecting to the
4728 remote system; the ``load'' command will download a program into the
4729 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4730 also supports debugging of realtime processes running under VxWorks,
4731 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4732 stub on the target system.
4734 New CPUs supported include the AMD 29000 and Intel 960.
4736 GDB now reads object files and symbol tables via a ``binary file''
4737 library, which allows a single copy of GDB to debug programs of multiple
4738 object file types such as a.out and coff.
4740 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4741 refcard.dvi and refcard.ps are available to format it).
4744 * Control-Variable user interface simplified
4746 All variables that control the operation of the debugger can be set
4747 by the ``set'' command, and displayed by the ``show'' command.
4749 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4750 ``Show prompt'' produces the response:
4751 Gdb's prompt is new-gdb=>.
4753 What follows are the NEW set commands. The command ``help set'' will
4754 print a complete list of old and new set commands. ``help set FOO''
4755 will give a longer description of the variable FOO. ``show'' will show
4756 all of the variable descriptions and their current settings.
4758 confirm on/off: Enables warning questions for operations that are
4759 hard to recover from, e.g. rerunning the program while
4760 it is already running. Default is ON.
4762 editing on/off: Enables EMACS style command line editing
4763 of input. Previous lines can be recalled with
4764 control-P, the current line can be edited with control-B,
4765 you can search for commands with control-R, etc.
4768 history filename NAME: NAME is where the gdb command history
4769 will be stored. The default is .gdb_history,
4770 or the value of the environment variable
4773 history size N: The size, in commands, of the command history. The
4774 default is 256, or the value of the environment variable
4777 history save on/off: If this value is set to ON, the history file will
4778 be saved after exiting gdb. If set to OFF, the
4779 file will not be saved. The default is OFF.
4781 history expansion on/off: If this value is set to ON, then csh-like
4782 history expansion will be performed on
4783 command line input. The default is OFF.
4785 radix N: Sets the default radix for input and output. It can be set
4786 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4787 in the current radix, so "set radix 10" is always a no-op.
4789 height N: This integer value is the number of lines on a page. Default
4790 is 24, the current `stty rows'' setting, or the ``li#''
4791 setting from the termcap entry matching the environment
4794 width N: This integer value is the number of characters on a line.
4795 Default is 80, the current `stty cols'' setting, or the ``co#''
4796 setting from the termcap entry matching the environment
4799 Note: ``set screensize'' is obsolete. Use ``set height'' and
4800 ``set width'' instead.
4802 print address on/off: Print memory addresses in various command displays,
4803 such as stack traces and structure values. Gdb looks
4804 more ``symbolic'' if you turn this off; it looks more
4805 ``machine level'' with it on. Default is ON.
4807 print array on/off: Prettyprint arrays. New convenient format! Default
4810 print demangle on/off: Print C++ symbols in "source" form if on,
4813 print asm-demangle on/off: Same, for assembler level printouts
4816 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4819 * Support for Epoch Environment.
4821 The epoch environment is a version of Emacs v18 with windowing. One
4822 new command, ``inspect'', is identical to ``print'', except that if you
4823 are running in the epoch environment, the value is printed in its own
4827 * Support for Shared Libraries
4829 GDB can now debug programs and core files that use SunOS shared libraries.
4830 Symbols from a shared library cannot be referenced
4831 before the shared library has been linked with the program (this
4832 happens after you type ``run'' and before the function main() is entered).
4833 At any time after this linking (including when examining core files
4834 from dynamically linked programs), gdb reads the symbols from each
4835 shared library when you type the ``sharedlibrary'' command.
4836 It can be abbreviated ``share''.
4838 sharedlibrary REGEXP: Load shared object library symbols for files
4839 matching a unix regular expression. No argument
4840 indicates to load symbols for all shared libraries.
4842 info sharedlibrary: Status of loaded shared libraries.
4847 A watchpoint stops execution of a program whenever the value of an
4848 expression changes. Checking for this slows down execution
4849 tremendously whenever you are in the scope of the expression, but is
4850 quite useful for catching tough ``bit-spreader'' or pointer misuse
4851 problems. Some machines such as the 386 have hardware for doing this
4852 more quickly, and future versions of gdb will use this hardware.
4854 watch EXP: Set a watchpoint (breakpoint) for an expression.
4856 info watchpoints: Information about your watchpoints.
4858 delete N: Deletes watchpoint number N (same as breakpoints).
4859 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4860 enable N: Re-enables watchpoint number N (same as breakpoints).
4863 * C++ multiple inheritance
4865 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4868 * C++ exception handling
4870 Gdb now supports limited C++ exception handling. Besides the existing
4871 ability to breakpoint on an exception handler, gdb can breakpoint on
4872 the raising of an exception (before the stack is peeled back to the
4875 catch FOO: If there is a FOO exception handler in the dynamic scope,
4876 set a breakpoint to catch exceptions which may be raised there.
4877 Multiple exceptions (``catch foo bar baz'') may be caught.
4879 info catch: Lists all exceptions which may be caught in the
4880 current stack frame.
4883 * Minor command changes
4885 The command ``call func (arg, arg, ...)'' now acts like the print
4886 command, except it does not print or save a value if the function's result
4887 is void. This is similar to dbx usage.
4889 The ``up'' and ``down'' commands now always print the frame they end up
4890 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4891 frames without printing.
4893 * New directory command
4895 'dir' now adds directories to the FRONT of the source search path.
4896 The path starts off empty. Source files that contain debug information
4897 about the directory in which they were compiled can be found even
4898 with an empty path; Sun CC and GCC include this information. If GDB can't
4899 find your source file in the current directory, type "dir .".
4901 * Configuring GDB for compilation
4903 For normal use, type ``./configure host''. See README or gdb.texinfo
4906 GDB now handles cross debugging. If you are remotely debugging between
4907 two different machines, type ``./configure host -target=targ''.
4908 Host is the machine where GDB will run; targ is the machine
4909 where the program that you are debugging will run.