1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.4
8 ** The "maint set python print-stack on|off" is now deleted.
10 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
11 apply "flag enum"-style pretty-printing to any enum.
13 * GDBserver now supports stdio connections.
14 E.g. (gdb) target remote | ssh myhost gdbserver - hello
16 * The binary "gdbtui" can no longer be built or installed.
17 Use "gdb -tui" instead.
19 * GDB will now print "flag" enums specially. A flag enum is one where
20 all the enumerator values have no bits in common when pairwise
21 "and"ed. When printing a value whose type is a flag enum, GDB will
22 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
23 (gdb) print (enum E) 3
26 * The filename part of a linespec will now match trailing components
27 of a source file name. For example, "break gcc/expr.c:1000" will
28 now set a breakpoint in build/gcc/expr.c, but not
31 *** Changes in GDB 7.4
33 * GDB now handles ambiguous linespecs more consistently; the existing
34 FILE:LINE support has been expanded to other types of linespecs. A
35 breakpoint will now be set on all matching locations in all
36 inferiors, and locations will be added or removed according to
39 * GDB now allows you to skip uninteresting functions and files when
40 stepping with the "skip function" and "skip file" commands.
42 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
43 and "show remote hardware-watchpoint-length-limit". These allows to
44 set or show the maximum length limit (in bytes) of a remote
45 target hardware watchpoint.
47 This allows e.g. to use "unlimited" hardware watchpoints with the
48 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
49 watchpoints are slower than real hardware watchpoints but are
50 significantly faster than gdb software watchpoints.
54 ** The register_pretty_printer function in module gdb.printing now takes
55 an optional `replace' argument. If True, the new printer replaces any
58 ** The "maint set python print-stack on|off" command has been
59 deprecated and will be deleted in GDB 7.5.
60 A new command: "set python print-stack none|full|message" has
61 replaced it. Additionally, the default for "print-stack" is
62 now "message", which just prints the error message without
65 ** A prompt substitution hook (prompt_hook) is now available to the
68 ** A new Python module, gdb.prompt has been added to the GDB Python
69 modules library. This module provides functionality for
70 escape sequences in prompts (used by set/show
71 extended-prompt). These escape sequences are replaced by their
74 ** Python commands and convenience-functions located in
75 'data-directory'/python/gdb/command and
76 'data-directory'/python/gdb/function are now automatically loaded
79 ** Blocks now provide four new attributes. global_block and
80 static_block will return the global and static blocks
81 respectively. is_static and is_global are boolean attributes
82 that indicate if the block is one of those two types.
84 ** Symbols now provide the "type" attribute, the type of the symbol.
86 ** The "gdb.breakpoint" function has been deprecated in favor of
89 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
90 of a function. This class is based on the "finish" command
93 ** Type objects for struct and union types now allow access to
94 the fields using standard Python dictionary (mapping) methods.
95 For example, "some_type['myfield']" now works, as does
98 ** A new event "gdb.new_objfile" has been added, triggered by loading a
101 ** A new function, "deep_items" has been added to the gdb.types
102 module in the GDB Python modules library. This function returns
103 an iterator over the fields of a struct or union type. Unlike
104 the standard Python "iteritems" method, it will recursively traverse
105 any anonymous fields.
109 ** "*stopped" events can report several new "reason"s, such as
112 ** Breakpoint changes are now notified using new async records, like
113 "=breakpoint-modified".
115 ** New command -ada-task-info.
117 * libthread-db-search-path now supports two special values: $sdir and $pdir.
118 $sdir specifies the default system locations of shared libraries.
119 $pdir specifies the directory where the libpthread used by the application
122 GDB no longer looks in $sdir and $pdir after it has searched the directories
123 mentioned in libthread-db-search-path. If you want to search those
124 directories, they must be specified in libthread-db-search-path.
125 The default value of libthread-db-search-path on GNU/Linux and Solaris
126 systems is now "$sdir:$pdir".
128 $pdir is not supported by gdbserver, it is currently ignored.
129 $sdir is supported by gdbserver.
131 * New configure option --with-iconv-bin.
132 When using the internationalization support like the one in the GNU C
133 library, GDB will invoke the "iconv" program to get a list of supported
134 character sets. If this program lives in a non-standard location, one can
135 use this option to specify where to find it.
137 * When natively debugging programs on PowerPC BookE processors running
138 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
139 watchpoints, which specify a mask in addition to an address to watch.
140 The mask specifies that some bits of an address (the bits which are
141 reset in the mask) should be ignored when matching the address accessed
142 by the inferior against the watchpoint address. See the "PowerPC Embedded"
143 section in the user manual for more details.
145 * The new option --once causes GDBserver to stop listening for connections once
146 the first connection is made. The listening port used by GDBserver will
147 become available after that.
149 * New commands "info macros" and "alias" have been added.
151 * New function parameters suffix @entry specifies value of function parameter
152 at the time the function got called. Entry values are available only since
158 "!" is now an alias of the "shell" command.
159 Note that no space is needed between "!" and SHELL COMMAND.
163 watch EXPRESSION mask MASK_VALUE
164 The watch command now supports the mask argument which allows creation
165 of masked watchpoints, if the current architecture supports this feature.
167 info auto-load-scripts [REGEXP]
168 This command was formerly named "maintenance print section-scripts".
169 It is now generally useful and is no longer a maintenance-only command.
171 info macro [-all] [--] MACRO
172 The info macro command has new options `-all' and `--'. The first for
173 printing all definitions of a macro. The second for explicitly specifying
174 the end of arguments and the beginning of the macro name in case the macro
175 name starts with a hyphen.
177 collect[/s] EXPRESSIONS
178 The tracepoint collect command now takes an optional modifier "/s"
179 that directs it to dereference pointer-to-character types and
180 collect the bytes of memory up to a zero byte. The behavior is
181 similar to what you see when you use the regular print command on a
182 string. An optional integer following the "/s" sets a bound on the
183 number of bytes that will be collected.
186 The trace start command now interprets any supplied arguments as a
187 note to be recorded with the trace run, with an effect similar to
188 setting the variable trace-notes.
191 The trace stop command now interprets any arguments as a note to be
192 mentioned along with the tstatus report that the trace was stopped
193 with a command. The effect is similar to setting the variable
196 * Tracepoints can now be enabled and disabled at any time after a trace
197 experiment has been started using the standard "enable" and "disable"
198 commands. It is now possible to start a trace experiment with no enabled
199 tracepoints; GDB will display a warning, but will allow the experiment to
200 begin, assuming that tracepoints will be enabled as needed while the trace
203 * Fast tracepoints on 32-bit x86-architectures can now be placed at
204 locations with 4-byte instructions, when they were previously
205 limited to locations with instructions of 5 bytes or longer.
211 Set the GDB prompt, and allow escape sequences to be inserted to
212 display miscellaneous information (see 'help set extended-prompt'
213 for the list of sequences). This prompt (and any information
214 accessed through the escape sequences) is updated every time the
217 set print entry-values (both|compact|default|if-needed|no|only|preferred)
218 show print entry-values
219 Set printing of frame argument values at function entry. In some cases
220 GDB can determine the value of function argument which was passed by the
221 function caller, even if the value was modified inside the called function.
223 set debug entry-values
224 show debug entry-values
225 Control display of debugging info for determining frame argument values at
226 function entry and virtual tail call frames.
228 set basenames-may-differ
229 show basenames-may-differ
230 Set whether a source file may have multiple base names.
231 (A "base name" is the name of a file with the directory part removed.
232 Example: The base name of "/home/user/hello.c" is "hello.c".)
233 If set, GDB will canonicalize file names (e.g., expand symlinks)
234 before comparing them. Canonicalization is an expensive operation,
235 but it allows the same file be known by more than one base name.
236 If not set (the default), all source files are assumed to have just
237 one base name, and gdb will do file name comparisons more efficiently.
243 Set a user name and notes for the current and any future trace runs.
244 This is useful for long-running and/or disconnected traces, to
245 inform others (or yourself) as to who is running the trace, supply
246 contact information, or otherwise explain what is going on.
249 show trace-stop-notes
250 Set a note attached to the trace run, that is displayed when the
251 trace has been stopped by a tstop command. This is useful for
252 instance as an explanation, if you are stopping a trace run that was
253 started by someone else.
259 Dynamically enable a tracepoint in a started trace experiment.
263 Dynamically disable a tracepoint in a started trace experiment.
267 Set the user and notes of the trace run.
271 Query the current status of a tracepoint.
275 Query the minimum length of instruction at which a fast tracepoint may
278 * Dcache size (number of lines) and line-size are now runtime-configurable
279 via "set dcache line" and "set dcache line-size" commands.
283 Texas Instruments TMS320C6x tic6x-*-*
287 Renesas RL78 rl78-*-elf
289 *** Changes in GDB 7.3.1
291 * The build failure for NetBSD and OpenBSD targets have now been fixed.
293 *** Changes in GDB 7.3
295 * GDB has a new command: "thread find [REGEXP]".
296 It finds the thread id whose name, target id, or thread extra info
297 matches the given regular expression.
299 * The "catch syscall" command now works on mips*-linux* targets.
301 * The -data-disassemble MI command now supports modes 2 and 3 for
302 dumping the instruction opcodes.
304 * New command line options
306 -data-directory DIR Specify DIR as the "data-directory".
307 This is mostly for testing purposes.
309 * The "maint set python auto-load on|off" command has been renamed to
310 "set auto-load-scripts on|off".
312 * GDB has a new command: "set directories".
313 It is like the "dir" command except that it replaces the
314 source path list instead of augmenting it.
316 * GDB now understands thread names.
318 On GNU/Linux, "info threads" will display the thread name as set by
319 prctl or pthread_setname_np.
321 There is also a new command, "thread name", which can be used to
322 assign a name internally for GDB to display.
325 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
326 has been integrated into GDB.
330 ** The function gdb.Write now accepts an optional keyword 'stream'.
331 This keyword, when provided, will direct the output to either
332 stdout, stderr, or GDB's logging output.
334 ** Parameters can now be be sub-classed in Python, and in particular
335 you may implement the get_set_doc and get_show_doc functions.
336 This improves how Parameter set/show documentation is processed
337 and allows for more dynamic content.
339 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
340 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
341 have an is_valid method.
343 ** Breakpoints can now be sub-classed in Python, and in particular
344 you may implement a 'stop' function that is executed each time
345 the inferior reaches that breakpoint.
347 ** New function gdb.lookup_global_symbol looks up a global symbol.
349 ** GDB values in Python are now callable if the value represents a
350 function. For example, if 'some_value' represents a function that
351 takes two integer parameters and returns a value, you can call
352 that function like so:
354 result = some_value (10,20)
356 ** Module gdb.types has been added.
357 It contains a collection of utilities for working with gdb.Types objects:
358 get_basic_type, has_field, make_enum_dict.
360 ** Module gdb.printing has been added.
361 It contains utilities for writing and registering pretty-printers.
362 New classes: PrettyPrinter, SubPrettyPrinter,
363 RegexpCollectionPrettyPrinter.
364 New function: register_pretty_printer.
366 ** New commands "info pretty-printers", "enable pretty-printer" and
367 "disable pretty-printer" have been added.
369 ** gdb.parameter("directories") is now available.
371 ** New function gdb.newest_frame returns the newest frame in the
374 ** The gdb.InferiorThread class has a new "name" attribute. This
375 holds the thread's name.
377 ** Python Support for Inferior events.
378 Python scripts can add observers to be notified of events
379 occurring in the process being debugged.
380 The following events are currently supported:
381 - gdb.events.cont Continue event.
382 - gdb.events.exited Inferior exited event.
383 - gdb.events.stop Signal received, and Breakpoint hit events.
387 ** GDB now puts template parameters in scope when debugging in an
388 instantiation. For example, if you have:
390 template<int X> int func (void) { return X; }
392 then if you step into func<5>, "print X" will show "5". This
393 feature requires proper debuginfo support from the compiler; it
394 was added to GCC 4.5.
396 ** The motion commands "next", "finish", "until", and "advance" now
397 work better when exceptions are thrown. In particular, GDB will
398 no longer lose control of the inferior; instead, the GDB will
399 stop the inferior at the point at which the exception is caught.
400 This functionality requires a change in the exception handling
401 code that was introduced in GCC 4.5.
403 * GDB now follows GCC's rules on accessing volatile objects when
404 reading or writing target state during expression evaluation.
405 One notable difference to prior behavior is that "print x = 0"
406 no longer generates a read of x; the value of the assignment is
407 now always taken directly from the value being assigned.
409 * GDB now has some support for using labels in the program's source in
410 linespecs. For instance, you can use "advance label" to continue
411 execution to a label.
413 * GDB now has support for reading and writing a new .gdb_index
414 section. This section holds a fast index of DWARF debugging
415 information and can be used to greatly speed up GDB startup and
416 operation. See the documentation for `save gdb-index' for details.
418 * The "watch" command now accepts an optional "-location" argument.
419 When used, this causes GDB to watch the memory referred to by the
420 expression. Such a watchpoint is never deleted due to it going out
423 * GDB now supports thread debugging of core dumps on GNU/Linux.
425 GDB now activates thread debugging using the libthread_db library
426 when debugging GNU/Linux core dumps, similarly to when debugging
427 live processes. As a result, when debugging a core dump file, GDB
428 is now able to display pthread_t ids of threads. For example, "info
429 threads" shows the same output as when debugging the process when it
430 was live. In earlier releases, you'd see something like this:
433 * 1 LWP 6780 main () at main.c:10
435 While now you see this:
438 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
440 It is also now possible to inspect TLS variables when debugging core
443 When debugging a core dump generated on a machine other than the one
444 used to run GDB, you may need to point GDB at the correct
445 libthread_db library with the "set libthread-db-search-path"
446 command. See the user manual for more details on this command.
448 * When natively debugging programs on PowerPC BookE processors running
449 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
450 which stop execution of the inferior whenever it executes an instruction
451 at any address within the specified range. See the "PowerPC Embedded"
452 section in the user manual for more details.
454 * New features in the GDB remote stub, GDBserver
456 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
457 and i686 LynxOS (version 5.x).
459 ** GDBserver is now supported on Blackfin Linux.
461 * New native configurations
463 ia64 HP-UX ia64-*-hpux*
467 Analog Devices, Inc. Blackfin Processor bfin-*
469 * Ada task switching is now supported on sparc-elf targets when
470 debugging a program using the Ravenscar Profile. For more information,
471 see the "Tasking Support when using the Ravenscar Profile" section
472 in the GDB user manual.
474 * Guile support was removed.
476 * New features in the GNU simulator
478 ** The --map-info flag lists all known core mappings.
480 ** CFI flashes may be simulated via the "cfi" device.
482 *** Changes in GDB 7.2
484 * Shared library support for remote targets by default
486 When GDB is configured for a generic, non-OS specific target, like
487 for example, --target=arm-eabi or one of the many *-*-elf targets,
488 GDB now queries remote stubs for loaded shared libraries using the
489 `qXfer:libraries:read' packet. Previously, shared library support
490 was always disabled for such configurations.
494 ** Argument Dependent Lookup (ADL)
496 In C++ ADL lookup directs function search to the namespaces of its
497 arguments even if the namespace has not been imported.
507 Here the compiler will search for `foo' in the namespace of 'b'
508 and find A::foo. GDB now supports this. This construct is commonly
509 used in the Standard Template Library for operators.
511 ** Improved User Defined Operator Support
513 In addition to member operators, GDB now supports lookup of operators
514 defined in a namespace and imported with a `using' directive, operators
515 defined in the global scope, operators imported implicitly from an
516 anonymous namespace, and the ADL operators mentioned in the previous
518 GDB now also supports proper overload resolution for all the previously
519 mentioned flavors of operators.
521 ** static const class members
523 Printing of static const class members that are initialized in the
524 class definition has been fixed.
526 * Windows Thread Information Block access.
528 On Windows targets, GDB now supports displaying the Windows Thread
529 Information Block (TIB) structure. This structure is visible either
530 by using the new command `info w32 thread-information-block' or, by
531 dereferencing the new convenience variable named `$_tlb', a
532 thread-specific pointer to the TIB. This feature is also supported
533 when remote debugging using GDBserver.
537 Static tracepoints are calls in the user program into a tracing
538 library. One such library is a port of the LTTng kernel tracer to
539 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
540 When debugging with GDBserver, GDB now supports combining the GDB
541 tracepoint machinery with such libraries. For example: the user can
542 use GDB to probe a static tracepoint marker (a call from the user
543 program into the tracing library) with the new "strace" command (see
544 "New commands" below). This creates a "static tracepoint" in the
545 breakpoint list, that can be manipulated with the same feature set
546 as fast and regular tracepoints. E.g., collect registers, local and
547 global variables, collect trace state variables, and define
548 tracepoint conditions. In addition, the user can collect extra
549 static tracepoint marker specific data, by collecting the new
550 $_sdata internal variable. When analyzing the trace buffer, you can
551 inspect $_sdata like any other variable available to GDB. For more
552 information, see the "Tracepoints" chapter in GDB user manual. New
553 remote packets have been defined to support static tracepoints, see
554 the "New remote packets" section below.
556 * Better reconstruction of tracepoints after disconnected tracing
558 GDB will attempt to download the original source form of tracepoint
559 definitions when starting a trace run, and then will upload these
560 upon reconnection to the target, resulting in a more accurate
561 reconstruction of the tracepoints that are in use on the target.
565 You can now exercise direct control over the ways that GDB can
566 affect your program. For instance, you can disallow the setting of
567 breakpoints, so that the program can run continuously (assuming
568 non-stop mode). In addition, the "observer" variable is available
569 to switch all of the different controls; in observer mode, GDB
570 cannot affect the target's behavior at all, which is useful for
571 tasks like diagnosing live systems in the field.
573 * The new convenience variable $_thread holds the number of the
580 Return the address of the Windows Thread Information Block of a given thread.
584 In response to several of the tracepoint packets, the target may now
585 also respond with a number of intermediate `qRelocInsn' request
586 packets before the final result packet, to have GDB handle
587 relocating an instruction to execute at a different address. This
588 is particularly useful for stubs that support fast tracepoints. GDB
589 reports support for this feature in the qSupported packet.
593 List static tracepoint markers in the target program.
597 List static tracepoint markers at a given address in the target
600 qXfer:statictrace:read
602 Read the static trace data collected (by a `collect $_sdata'
603 tracepoint action). The remote stub reports support for this packet
604 to gdb's qSupported query.
608 Send the current settings of GDB's permission flags.
612 Send part of the source (textual) form of a tracepoint definition,
613 which includes location, conditional, and action list.
615 * The source command now accepts a -s option to force searching for the
616 script in the source search path even if the script name specifies
619 * New features in the GDB remote stub, GDBserver
621 - GDBserver now support tracepoints (including fast tracepoints, and
622 static tracepoints). The feature is currently supported by the
623 i386-linux and amd64-linux builds. See the "Tracepoints support
624 in gdbserver" section in the manual for more information.
626 GDBserver JIT compiles the tracepoint's conditional agent
627 expression bytecode into native code whenever possible for low
628 overhead dynamic tracepoints conditionals. For such tracepoints,
629 an expression that examines program state is evaluated when the
630 tracepoint is reached, in order to determine whether to capture
631 trace data. If the condition is simple and false, processing the
632 tracepoint finishes very quickly and no data is gathered.
634 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
635 for static tracepoints support.
637 - GDBserver now supports x86_64 Windows 64-bit debugging.
639 * GDB now sends xmlRegisters= in qSupported packet to indicate that
640 it understands register description.
642 * The --batch flag now disables pagination and queries.
644 * X86 general purpose registers
646 GDB now supports reading/writing byte, word and double-word x86
647 general purpose registers directly. This means you can use, say,
648 $ah or $ax to refer, respectively, to the byte register AH and
649 16-bit word register AX that are actually portions of the 32-bit
650 register EAX or 64-bit register RAX.
652 * The `commands' command now accepts a range of breakpoints to modify.
653 A plain `commands' following a command that creates multiple
654 breakpoints affects all the breakpoints set by that command. This
655 applies to breakpoints set by `rbreak', and also applies when a
656 single `break' command creates multiple breakpoints (e.g.,
657 breakpoints on overloaded c++ functions).
659 * The `rbreak' command now accepts a filename specification as part of
660 its argument, limiting the functions selected by the regex to those
661 in the specified file.
663 * Support for remote debugging Windows and SymbianOS shared libraries
664 from Unix hosts has been improved. Non Windows GDB builds now can
665 understand target reported file names that follow MS-DOS based file
666 system semantics, such as file names that include drive letters and
667 use the backslash character as directory separator. This makes it
668 possible to transparently use the "set sysroot" and "set
669 solib-search-path" on Unix hosts to point as host copies of the
670 target's shared libraries. See the new command "set
671 target-file-system-kind" described below, and the "Commands to
672 specify files" section in the user manual for more information.
676 eval template, expressions...
677 Convert the values of one or more expressions under the control
678 of the string template to a command line, and call it.
680 set target-file-system-kind unix|dos-based|auto
681 show target-file-system-kind
682 Set or show the assumed file system kind for target reported file
685 save breakpoints <filename>
686 Save all current breakpoint definitions to a file suitable for use
687 in a later debugging session. To read the saved breakpoint
688 definitions, use the `source' command.
690 `save tracepoints' is a new alias for `save-tracepoints'. The latter
693 info static-tracepoint-markers
694 Display information about static tracepoint markers in the target.
696 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
697 Define a static tracepoint by probing a marker at the given
698 function, line, address, or marker ID.
702 Enable and disable observer mode.
704 set may-write-registers on|off
705 set may-write-memory on|off
706 set may-insert-breakpoints on|off
707 set may-insert-tracepoints on|off
708 set may-insert-fast-tracepoints on|off
709 set may-interrupt on|off
710 Set individual permissions for GDB effects on the target. Note that
711 some of these settings can have undesirable or surprising
712 consequences, particularly when changed in the middle of a session.
713 For instance, disabling the writing of memory can prevent
714 breakpoints from being inserted, cause single-stepping to fail, or
715 even crash your program, if you disable after breakpoints have been
716 inserted. However, GDB should not crash.
718 set record memory-query on|off
719 show record memory-query
720 Control whether to stop the inferior if memory changes caused
721 by an instruction cannot be recorded.
726 The disassemble command now supports "start,+length" form of two arguments.
730 ** GDB now provides a new directory location, called the python directory,
731 where Python scripts written for GDB can be installed. The location
732 of that directory is <data-directory>/python, where <data-directory>
733 is the GDB data directory. For more details, see section `Scripting
734 GDB using Python' in the manual.
736 ** The GDB Python API now has access to breakpoints, symbols, symbol
737 tables, program spaces, inferiors, threads and frame's code blocks.
738 Additionally, GDB Parameters can now be created from the API, and
739 manipulated via set/show in the CLI.
741 ** New functions gdb.target_charset, gdb.target_wide_charset,
742 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
744 ** New exception gdb.GdbError.
746 ** Pretty-printers are now also looked up in the current program space.
748 ** Pretty-printers can now be individually enabled and disabled.
750 ** GDB now looks for names of Python scripts to auto-load in a
751 special section named `.debug_gdb_scripts', in addition to looking
752 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
754 * Tracepoint actions were unified with breakpoint commands. In particular,
755 there are no longer differences in "info break" output for breakpoints and
756 tracepoints and the "commands" command can be used for both tracepoints and
761 ARM Symbian arm*-*-symbianelf*
763 * D language support.
764 GDB now supports debugging programs written in the D programming
767 * GDB now supports the extended ptrace interface for PowerPC which is
768 available since Linux kernel version 2.6.34. This automatically enables
769 any hardware breakpoints and additional hardware watchpoints available in
770 the processor. The old ptrace interface exposes just one hardware
771 watchpoint and no hardware breakpoints.
773 * GDB is now able to use the Data Value Compare (DVC) register available on
774 embedded PowerPC processors to implement in hardware simple watchpoint
775 conditions of the form:
777 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
779 This works in native GDB running on Linux kernels with the extended ptrace
780 interface mentioned above.
782 *** Changes in GDB 7.1
788 GDB now supports importing of namespaces in C++. This enables the
789 user to inspect variables from imported namespaces. Support for
790 namepace aliasing has also been added. So, if a namespace is
791 aliased in the current scope (e.g. namepace C=A; ) the user can
792 print variables using the alias (e.g. (gdb) print C::x).
796 All known bugs relating to the printing of virtual base class were
797 fixed. It is now possible to call overloaded static methods using a
802 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
803 and reinterpret_cast<> are now handled by the C++ expression parser.
807 Xilinx MicroBlaze microblaze-*-*
812 Xilinx MicroBlaze microblaze
815 * Multi-program debugging.
817 GDB now has support for multi-program (a.k.a. multi-executable or
818 multi-exec) debugging. This allows for debugging multiple inferiors
819 simultaneously each running a different program under the same GDB
820 session. See "Debugging Multiple Inferiors and Programs" in the
821 manual for more information. This implied some user visible changes
822 in the multi-inferior support. For example, "info inferiors" now
823 lists inferiors that are not running yet or that have exited
824 already. See also "New commands" and "New options" below.
826 * New tracing features
828 GDB's tracepoint facility now includes several new features:
830 ** Trace state variables
832 GDB tracepoints now include support for trace state variables, which
833 are variables managed by the target agent during a tracing
834 experiment. They are useful for tracepoints that trigger each
835 other, so for instance one tracepoint can count hits in a variable,
836 and then a second tracepoint has a condition that is true when the
837 count reaches a particular value. Trace state variables share the
838 $-syntax of GDB convenience variables, and can appear in both
839 tracepoint actions and condition expressions. Use the "tvariable"
840 command to create, and "info tvariables" to view; see "Trace State
841 Variables" in the manual for more detail.
845 GDB now includes an option for defining fast tracepoints, which
846 targets may implement more efficiently, such as by installing a jump
847 into the target agent rather than a trap instruction. The resulting
848 speedup can be by two orders of magnitude or more, although the
849 tradeoff is that some program locations on some target architectures
850 might not allow fast tracepoint installation, for instance if the
851 instruction to be replaced is shorter than the jump. To request a
852 fast tracepoint, use the "ftrace" command, with syntax identical to
853 the regular trace command.
855 ** Disconnected tracing
857 It is now possible to detach GDB from the target while it is running
858 a trace experiment, then reconnect later to see how the experiment
859 is going. In addition, a new variable disconnected-tracing lets you
860 tell the target agent whether to continue running a trace if the
861 connection is lost unexpectedly.
865 GDB now has the ability to save the trace buffer into a file, and
866 then use that file as a target, similarly to you can do with
867 corefiles. You can select trace frames, print data that was
868 collected in them, and use tstatus to display the state of the
869 tracing run at the moment that it was saved. To create a trace
870 file, use "tsave <filename>", and to use it, do "target tfile
873 ** Circular trace buffer
875 You can ask the target agent to handle the trace buffer as a
876 circular buffer, discarding the oldest trace frames to make room for
877 newer ones, by setting circular-trace-buffer to on. This feature may
878 not be available for all target agents.
883 The disassemble command, when invoked with two arguments, now requires
884 the arguments to be comma-separated.
887 The info variables command now displays variable definitions. Files
888 which only declare a variable are not shown.
891 The source command is now capable of sourcing Python scripts.
892 This feature is dependent on the debugger being build with Python
895 Related to this enhancement is also the introduction of a new command
896 "set script-extension" (see below).
898 * New commands (for set/show, see "New options" below)
900 record save [<FILENAME>]
901 Save a file (in core file format) containing the process record
902 execution log for replay debugging at a later time.
904 record restore <FILENAME>
905 Restore the process record execution log that was saved at an
906 earlier time, for replay debugging.
908 add-inferior [-copies <N>] [-exec <FILENAME>]
911 clone-inferior [-copies <N>] [ID]
912 Make a new inferior ready to execute the same program another
918 maint info program-spaces
919 List the program spaces loaded into GDB.
921 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
922 show remote interrupt-sequence
923 Allow the user to select one of ^C, a BREAK signal or BREAK-g
924 as the sequence to the remote target in order to interrupt the execution.
925 Ctrl-C is a default. Some system prefers BREAK which is high level of
926 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
927 Magic SysRq g. It is BREAK signal and character 'g'.
929 set remote interrupt-on-connect [on | off]
930 show remote interrupt-on-connect
931 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
932 remote target when gdb connects to it. This is needed when you debug
935 set remotebreak [on | off]
937 Deprecated. Use "set/show remote interrupt-sequence" instead.
939 tvariable $NAME [ = EXP ]
940 Create or modify a trace state variable.
943 List trace state variables and their values.
945 delete tvariable $NAME ...
946 Delete one or more trace state variables.
949 Evaluate the given expressions without collecting anything into the
950 trace buffer. (Valid in tracepoint actions only.)
952 ftrace FN / FILE:LINE / *ADDR
953 Define a fast tracepoint at the given function, line, or address.
955 * New expression syntax
957 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
958 GDB now parses 0b101010 identically with 42.
962 set follow-exec-mode new|same
963 show follow-exec-mode
964 Control whether GDB reuses the same inferior across an exec call or
965 creates a new one. This is useful to be able to restart the old
966 executable after the inferior having done an exec call.
968 set default-collect EXPR, ...
970 Define a list of expressions to be collected at each tracepoint.
971 This is a useful way to ensure essential items are not overlooked,
972 such as registers or a critical global variable.
974 set disconnected-tracing
975 show disconnected-tracing
976 If set to 1, the target is instructed to continue tracing if it
977 loses its connection to GDB. If 0, the target is to stop tracing
980 set circular-trace-buffer
981 show circular-trace-buffer
982 If set to on, the target is instructed to use a circular trace buffer
983 and discard the oldest trace frames instead of stopping the trace due
984 to a full trace buffer. If set to off, the trace stops when the buffer
985 fills up. Some targets may not support this.
987 set script-extension off|soft|strict
988 show script-extension
989 If set to "off", the debugger does not perform any script language
990 recognition, and all sourced files are assumed to be GDB scripts.
991 If set to "soft" (the default), files are sourced according to
992 filename extension, falling back to GDB scripts if the first
994 If set to "strict", files are sourced according to filename extension.
996 set ada trust-PAD-over-XVS on|off
997 show ada trust-PAD-over-XVS
998 If off, activate a workaround against a bug in the debugging information
999 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1000 the GCC sources for more information about the GNAT encoding and
1001 PAD types in particular). It is always safe to set this option to
1002 off, but this introduces a slight performance penalty. The default
1005 * Python API Improvements
1007 ** GDB provides the new class gdb.LazyString. This is useful in
1008 some pretty-printing cases. The new method gdb.Value.lazy_string
1009 provides a simple way to create objects of this type.
1011 ** The fields returned by gdb.Type.fields now have an
1012 `is_base_class' attribute.
1014 ** The new method gdb.Type.range returns the range of an array type.
1016 ** The new method gdb.parse_and_eval can be used to parse and
1017 evaluate an expression.
1019 * New remote packets
1022 Define a trace state variable.
1025 Get the current value of a trace state variable.
1028 Set desired tracing behavior upon disconnection.
1031 Set the trace buffer to be linear or circular.
1034 Get data about the tracepoints currently in use.
1038 Process record now works correctly with hardware watchpoints.
1040 Multiple bug fixes have been made to the mips-irix port, making it
1041 much more reliable. In particular:
1042 - Debugging threaded applications is now possible again. Previously,
1043 GDB would hang while starting the program, or while waiting for
1044 the program to stop at a breakpoint.
1045 - Attaching to a running process no longer hangs.
1046 - An error occurring while loading a core file has been fixed.
1047 - Changing the value of the PC register now works again. This fixes
1048 problems observed when using the "jump" command, or when calling
1049 a function from GDB, or even when assigning a new value to $pc.
1050 - With the "finish" and "return" commands, the return value for functions
1051 returning a small array is now correctly printed.
1052 - It is now possible to break on shared library code which gets executed
1053 during a shared library init phase (code executed while executing
1054 their .init section). Previously, the breakpoint would have no effect.
1055 - GDB is now able to backtrace through the signal handler for
1056 non-threaded programs.
1058 PIE (Position Independent Executable) programs debugging is now supported.
1059 This includes debugging execution of PIC (Position Independent Code) shared
1060 libraries although for that, it should be possible to run such libraries as an
1063 *** Changes in GDB 7.0
1065 * GDB now has an interface for JIT compilation. Applications that
1066 dynamically generate code can create symbol files in memory and register
1067 them with GDB. For users, the feature should work transparently, and
1068 for JIT developers, the interface is documented in the GDB manual in the
1069 "JIT Compilation Interface" chapter.
1071 * Tracepoints may now be conditional. The syntax is as for
1072 breakpoints; either an "if" clause appended to the "trace" command,
1073 or the "condition" command is available. GDB sends the condition to
1074 the target for evaluation using the same bytecode format as is used
1075 for tracepoint actions.
1077 * The disassemble command now supports: an optional /r modifier, print the
1078 raw instructions in hex as well as in symbolic form, and an optional /m
1079 modifier to print mixed source+assembly.
1081 * Process record and replay
1083 In a architecture environment that supports ``process record and
1084 replay'', ``process record and replay'' target can record a log of
1085 the process execution, and replay it with both forward and reverse
1088 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1089 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1090 set execution-direction {forward|reverse}, for targets that support
1093 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1094 feature is available with a native GDB running on kernel version
1097 * GDB now has support for multi-byte and wide character sets on the
1098 target. Strings whose character type is wchar_t, char16_t, or
1099 char32_t are now correctly printed. GDB supports wide- and unicode-
1100 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1101 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1102 `printf'. This feature requires iconv to work properly; if your
1103 system does not have a working iconv, GDB can use GNU libiconv. See
1104 the installation instructions for more information.
1106 * GDB now supports automatic retrieval of shared library files from
1107 remote targets. To use this feature, specify a system root that begins
1108 with the `remote:' prefix, either via the `set sysroot' command or via
1109 the `--with-sysroot' configure-time option.
1111 * "info sharedlibrary" now takes an optional regex of libraries to show,
1112 and it now reports if a shared library has no debugging information.
1114 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1115 now complete on file names.
1117 * When completing in expressions, gdb will attempt to limit
1118 completions to allowable structure or union fields, where appropriate.
1119 For instance, consider:
1121 # struct example { int f1; double f2; };
1122 # struct example variable;
1125 If the user types TAB at the end of this command line, the available
1126 completions will be "f1" and "f2".
1128 * Inlined functions are now supported. They show up in backtraces, and
1129 the "step", "next", and "finish" commands handle them automatically.
1131 * GDB now supports the token-splicing (##) and stringification (#)
1132 operators when expanding macros. It also supports variable-arity
1135 * GDB now supports inspecting extra signal information, exported by
1136 the new $_siginfo convenience variable. The feature is currently
1137 implemented on linux ARM, i386 and amd64.
1139 * GDB can now display the VFP floating point registers and NEON vector
1140 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1141 can provide these registers (requires Linux 2.6.30 or later). Remote
1142 and simulator targets may also provide them.
1144 * New remote packets
1147 Search memory for a sequence of bytes.
1150 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1151 operation over reliable transport links. Use of this packet is
1152 controlled by the `set remote noack-packet' command.
1155 Kill the process with the specified process ID. Use this in preference
1156 to `k' when multiprocess protocol extensions are supported.
1159 Obtains additional operating system information
1163 Read or write additional signal information.
1165 * Removed remote protocol undocumented extension
1167 An undocumented extension to the remote protocol's `S' stop reply
1168 packet that permited the stub to pass a process id was removed.
1169 Remote servers should use the `T' stop reply packet instead.
1171 * GDB now supports multiple function calling conventions according to the
1172 DWARF-2 DW_AT_calling_convention function attribute.
1174 * The SH target utilizes the aforementioned change to distinguish between gcc
1175 and Renesas calling convention. It also adds the new CLI commands
1176 `set/show sh calling-convention'.
1178 * GDB can now read compressed debug sections, as produced by GNU gold
1179 with the --compress-debug-sections=zlib flag.
1181 * 64-bit core files are now supported on AIX.
1183 * Thread switching is now supported on Tru64.
1185 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1186 which will be allocated using malloc later in program execution.
1188 * The qXfer:libraries:read remote procotol packet now allows passing a
1189 list of section offsets.
1191 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1192 conditions handling signals delivered during attach or thread creation
1193 have also been fixed.
1195 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1196 From the user's standpoint, all unqualified instances of True and False
1197 are treated as the standard definitions, regardless of context.
1199 * GDB now parses C++ symbol and type names more flexibly. For
1202 template<typename T> class C { };
1205 GDB will now correctly handle all of:
1207 ptype C<char const *>
1208 ptype C<char const*>
1209 ptype C<const char *>
1210 ptype C<const char*>
1212 * New features in the GDB remote stub, gdbserver
1214 - The "--wrapper" command-line argument tells gdbserver to use a
1215 wrapper program to launch programs for debugging.
1217 - On PowerPC and S/390 targets, it is now possible to use a single
1218 gdbserver executable to debug both 32-bit and 64-bit programs.
1219 (This requires gdbserver itself to be built as a 64-bit executable.)
1221 - gdbserver uses the new noack protocol mode for TCP connections to
1222 reduce communications latency, if also supported and enabled in GDB.
1224 - Support for the sparc64-linux-gnu target is now included in
1227 - The amd64-linux build of gdbserver now supports debugging both
1228 32-bit and 64-bit programs.
1230 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1231 now support hardware watchpoints, and will use them automatically
1236 GDB now has support for scripting using Python. Whether this is
1237 available is determined at configure time.
1239 New GDB commands can now be written in Python.
1241 * Ada tasking support
1243 Ada tasks can now be inspected in GDB. The following commands have
1247 Print the list of Ada tasks.
1249 Print detailed information about task number N.
1251 Print the task number of the current task.
1253 Switch the context of debugging to task number N.
1255 * Support for user-defined prefixed commands. The "define" command can
1256 add new commands to existing prefixes, e.g. "target".
1258 * Multi-inferior, multi-process debugging.
1260 GDB now has generalized support for multi-inferior debugging. See
1261 "Debugging Multiple Inferiors" in the manual for more information.
1262 Although availability still depends on target support, the command
1263 set is more uniform now. The GNU/Linux specific multi-forks support
1264 has been migrated to this new framework. This implied some user
1265 visible changes; see "New commands" and also "Removed commands"
1268 * Target descriptions can now describe the target OS ABI. See the
1269 "Target Description Format" section in the user manual for more
1272 * Target descriptions can now describe "compatible" architectures
1273 to indicate that the target can execute applications for a different
1274 architecture in addition to those for the main target architecture.
1275 See the "Target Description Format" section in the user manual for
1278 * Multi-architecture debugging.
1280 GDB now includes general supports for debugging applications on
1281 hybrid systems that use more than one single processor architecture
1282 at the same time. Each such hybrid architecture still requires
1283 specific support to be added. The only hybrid architecture supported
1284 in this version of GDB is the Cell Broadband Engine.
1286 * GDB now supports integrated debugging of Cell/B.E. applications that
1287 use both the PPU and SPU architectures. To enable support for hybrid
1288 Cell/B.E. debugging, you need to configure GDB to support both the
1289 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1290 --enable-targets configure option.
1292 * Non-stop mode debugging.
1294 For some targets, GDB now supports an optional mode of operation in
1295 which you can examine stopped threads while other threads continue
1296 to execute freely. This is referred to as non-stop mode, with the
1297 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1298 section in the user manual for more information.
1300 To be able to support remote non-stop debugging, a remote stub needs
1301 to implement the non-stop mode remote protocol extensions, as
1302 described in the "Remote Non-Stop" section of the user manual. The
1303 GDB remote stub, gdbserver, has been adjusted to support these
1304 extensions on linux targets.
1306 * New commands (for set/show, see "New options" below)
1308 catch syscall [NAME(S) | NUMBER(S)]
1309 Catch system calls. Arguments, which should be names of system
1310 calls or their numbers, mean catch only those syscalls. Without
1311 arguments, every syscall will be caught. When the inferior issues
1312 any of the specified syscalls, GDB will stop and announce the system
1313 call, both when it is called and when its call returns. This
1314 feature is currently available with a native GDB running on the
1315 Linux Kernel, under the following architectures: x86, x86_64,
1316 PowerPC and PowerPC64.
1318 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1320 Search memory for a sequence of bytes.
1322 maint set python print-stack
1323 maint show python print-stack
1324 Show a stack trace when an error is encountered in a Python script.
1327 Invoke CODE by passing it to the Python interpreter.
1332 These allow macros to be defined, undefined, and listed
1336 Show operating system information about processes.
1339 List the inferiors currently under GDB's control.
1342 Switch focus to inferior number NUM.
1345 Detach from inferior number NUM.
1348 Kill inferior number NUM.
1352 set spu stop-on-load
1353 show spu stop-on-load
1354 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1356 set spu auto-flush-cache
1357 show spu auto-flush-cache
1358 Control whether to automatically flush the software-managed cache
1359 during Cell/B.E. debugging.
1361 set sh calling-convention
1362 show sh calling-convention
1363 Control the calling convention used when calling SH target functions.
1366 show debug timestamp
1367 Control display of timestamps with GDB debugging output.
1369 set disassemble-next-line
1370 show disassemble-next-line
1371 Control display of disassembled source lines or instructions when
1374 set remote noack-packet
1375 show remote noack-packet
1376 Set/show the use of remote protocol QStartNoAckMode packet. See above
1377 under "New remote packets."
1379 set remote query-attached-packet
1380 show remote query-attached-packet
1381 Control use of remote protocol `qAttached' (query-attached) packet.
1383 set remote read-siginfo-object
1384 show remote read-siginfo-object
1385 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1388 set remote write-siginfo-object
1389 show remote write-siginfo-object
1390 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1393 set remote reverse-continue
1394 show remote reverse-continue
1395 Control use of remote protocol 'bc' (reverse-continue) packet.
1397 set remote reverse-step
1398 show remote reverse-step
1399 Control use of remote protocol 'bs' (reverse-step) packet.
1401 set displaced-stepping
1402 show displaced-stepping
1403 Control displaced stepping mode. Displaced stepping is a way to
1404 single-step over breakpoints without removing them from the debuggee.
1405 Also known as "out-of-line single-stepping".
1408 show debug displaced
1409 Control display of debugging info for displaced stepping.
1411 maint set internal-error
1412 maint show internal-error
1413 Control what GDB does when an internal error is detected.
1415 maint set internal-warning
1416 maint show internal-warning
1417 Control what GDB does when an internal warning is detected.
1422 Use a wrapper program to launch programs for debugging.
1424 set multiple-symbols (all|ask|cancel)
1425 show multiple-symbols
1426 The value of this variable can be changed to adjust the debugger behavior
1427 when an expression or a breakpoint location contains an ambiguous symbol
1428 name (an overloaded function name, for instance).
1430 set breakpoint always-inserted
1431 show breakpoint always-inserted
1432 Keep breakpoints always inserted in the target, as opposed to inserting
1433 them when resuming the target, and removing them when the target stops.
1434 This option can improve debugger performance on slow remote targets.
1436 set arm fallback-mode (arm|thumb|auto)
1437 show arm fallback-mode
1438 set arm force-mode (arm|thumb|auto)
1440 These commands control how ARM GDB determines whether instructions
1441 are ARM or Thumb. The default for both settings is auto, which uses
1442 the current CPSR value for instructions without symbols; previous
1443 versions of GDB behaved as if "set arm fallback-mode arm".
1445 set disable-randomization
1446 show disable-randomization
1447 Standalone programs run with the virtual address space randomization enabled
1448 by default on some platforms. This option keeps the addresses stable across
1449 multiple debugging sessions.
1453 Control whether other threads are stopped or not when some thread hits
1458 Requests that asynchronous execution is enabled in the target, if available.
1459 In this case, it's possible to resume target in the background, and interact
1460 with GDB while the target is running. "show target-async" displays the
1461 current state of asynchronous execution of the target.
1463 set target-wide-charset
1464 show target-wide-charset
1465 The target-wide-charset is the name of the character set that GDB
1466 uses when printing characters whose type is wchar_t.
1468 set tcp auto-retry (on|off)
1470 set tcp connect-timeout
1471 show tcp connect-timeout
1472 These commands allow GDB to retry failed TCP connections to a remote stub
1473 with a specified timeout period; this is useful if the stub is launched
1474 in parallel with GDB but may not be ready to accept connections immediately.
1476 set libthread-db-search-path
1477 show libthread-db-search-path
1478 Control list of directories which GDB will search for appropriate
1481 set schedule-multiple (on|off)
1482 show schedule-multiple
1483 Allow GDB to resume all threads of all processes or only threads of
1484 the current process.
1488 Use more aggressive caching for accesses to the stack. This improves
1489 performance of remote debugging (particularly backtraces) without
1490 affecting correctness.
1492 set interactive-mode (on|off|auto)
1493 show interactive-mode
1494 Control whether GDB runs in interactive mode (on) or not (off).
1495 When in interactive mode, GDB waits for the user to answer all
1496 queries. Otherwise, GDB does not wait and assumes the default
1497 answer. When set to auto (the default), GDB determines which
1498 mode to use based on the stdin settings.
1503 For program forks, this is replaced by the new more generic `info
1504 inferiors' command. To list checkpoints, you can still use the
1505 `info checkpoints' command, which was an alias for the `info forks'
1509 Replaced by the new `inferior' command. To switch between
1510 checkpoints, you can still use the `restart' command, which was an
1511 alias for the `fork' command.
1514 This is removed, since some targets don't have a notion of
1515 processes. To switch between processes, you can still use the
1516 `inferior' command using GDB's own inferior number.
1519 For program forks, this is replaced by the new more generic `kill
1520 inferior' command. To delete a checkpoint, you can still use the
1521 `delete checkpoint' command, which was an alias for the `delete
1525 For program forks, this is replaced by the new more generic `detach
1526 inferior' command. To detach a checkpoint, you can still use the
1527 `detach checkpoint' command, which was an alias for the `detach
1530 * New native configurations
1532 x86/x86_64 Darwin i[34567]86-*-darwin*
1534 x86_64 MinGW x86_64-*-mingw*
1538 Lattice Mico32 lm32-*
1539 x86 DICOS i[34567]86-*-dicos*
1540 x86_64 DICOS x86_64-*-dicos*
1543 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1544 (mingw32ce) debugging.
1550 These commands were actually not implemented on any target.
1552 *** Changes in GDB 6.8
1554 * New native configurations
1556 NetBSD/hppa hppa*-*netbsd*
1557 Xtensa GNU/Linux xtensa*-*-linux*
1561 NetBSD/hppa hppa*-*-netbsd*
1562 Xtensa GNU/Lunux xtensa*-*-linux*
1564 * Change in command line behavior -- corefiles vs. process ids.
1566 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1567 attaching to process NUMBER fails, GDB no longer attempts to open a
1568 core file named NUMBER. Attaching to a program using the -c option
1569 is no longer supported. Instead, use the '-p' or '--pid' options.
1571 * GDB can now be built as a native debugger for debugging Windows x86
1572 (mingw32) Portable Executable (PE) programs.
1574 * Pending breakpoints no longer change their number when their address
1577 * GDB now supports breakpoints with multiple locations,
1578 including breakpoints on C++ constructors, inside C++ templates,
1579 and in inlined functions.
1581 * GDB's ability to debug optimized code has been improved. GDB more
1582 accurately identifies function bodies and lexical blocks that occupy
1583 more than one contiguous range of addresses.
1585 * Target descriptions can now describe registers for PowerPC.
1587 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1588 registers on PowerPC targets.
1590 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1591 targets even when the libthread_db library is not available.
1593 * The GDB remote stub, gdbserver, now supports the new file transfer
1594 commands (remote put, remote get, and remote delete).
1596 * The GDB remote stub, gdbserver, now supports run and attach in
1597 extended-remote mode.
1599 * hppa*64*-*-hpux11* target broken
1600 The debugger is unable to start a program and fails with the following
1601 error: "Error trying to get information about dynamic linker".
1602 The gdb-6.7 release is also affected.
1604 * GDB now supports the --enable-targets= configure option to allow
1605 building a single GDB executable that supports multiple remote
1606 target architectures.
1608 * GDB now supports debugging C and C++ programs which use the
1609 Decimal Floating Point extension. In addition, the PowerPC target
1610 now has a set of pseudo-registers to inspect decimal float values
1611 stored in two consecutive float registers.
1613 * The -break-insert MI command can optionally create pending
1616 * Improved support for debugging Ada
1617 Many improvements to the Ada language support have been made. These
1619 - Better support for Ada2005 interface types
1620 - Improved handling of arrays and slices in general
1621 - Better support for Taft-amendment types
1622 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1624 - Improved command completion in Ada
1627 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1632 set print frame-arguments (all|scalars|none)
1633 show print frame-arguments
1634 The value of this variable can be changed to control which argument
1635 values should be printed by the debugger when displaying a frame.
1640 Transfer files to and from a remote target, and delete remote files.
1647 Transfer files to and from a remote target, and delete remote files.
1649 * New remote packets
1656 Open, close, read, write, and delete files on the remote system.
1659 Attach to an existing process on the remote system, in extended-remote
1663 Run a new process on the remote system, in extended-remote mode.
1665 *** Changes in GDB 6.7
1667 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1668 bfd, libiberty and opcodes, as revealed by static analysis donated by
1669 Coverity, Inc. (http://scan.coverity.com).
1671 * When looking up multiply-defined global symbols, GDB will now prefer the
1672 symbol definition in the current shared library if it was built using the
1673 -Bsymbolic linker option.
1675 * When the Text User Interface (TUI) is not configured, GDB will now
1676 recognize the -tui command-line option and print a message that the TUI
1679 * The GDB remote stub, gdbserver, now has lower overhead for high
1680 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1682 * GDB for MIPS targets now autodetects whether a remote target provides
1683 32-bit or 64-bit register values.
1685 * Support for C++ member pointers has been improved.
1687 * GDB now understands XML target descriptions, which specify the
1688 target's overall architecture. GDB can read a description from
1689 a local file or over the remote serial protocol.
1691 * Vectors of single-byte data use a new integer type which is not
1692 automatically displayed as character or string data.
1694 * The /s format now works with the print command. It displays
1695 arrays of single-byte integers and pointers to single-byte integers
1698 * Target descriptions can now describe target-specific registers,
1699 for architectures which have implemented the support (currently
1700 only ARM, M68K, and MIPS).
1702 * GDB and the GDB remote stub, gdbserver, now support the XScale
1705 * The GDB remote stub, gdbserver, has been updated to support
1706 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1707 has been rewritten to use the standard GDB remote protocol.
1709 * GDB can now step into C++ functions which are called through thunks.
1711 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1713 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1714 layout. It also supports a TextSeg= and DataSeg= response when only
1715 segment base addresses (rather than offsets) are available.
1717 * The /i format now outputs any trailing branch delay slot instructions
1718 immediately following the last instruction within the count specified.
1720 * The GDB remote protocol "T" stop reply packet now supports a
1721 "library" response. Combined with the new "qXfer:libraries:read"
1722 packet, this response allows GDB to debug shared libraries on targets
1723 where the operating system manages the list of loaded libraries (e.g.
1724 Windows and SymbianOS).
1726 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1727 (DLLs) on Windows and Windows CE targets.
1729 * GDB now supports a faster verification that a .debug file matches its binary
1730 according to its build-id signature, if the signature is present.
1736 Enable or disable hardware flow control (RTS/CTS) on the serial port
1737 when debugging using remote targets.
1739 set mem inaccessible-by-default
1740 show mem inaccessible-by-default
1741 If the target supplies a memory map, for instance via the remote
1742 protocol's "qXfer:memory-map:read" packet, setting this variable
1743 prevents GDB from accessing memory outside the memory map. This
1744 is useful for targets with memory mapped registers or which react
1745 badly to accesses of unmapped address space.
1747 set breakpoint auto-hw
1748 show breakpoint auto-hw
1749 If the target supplies a memory map, for instance via the remote
1750 protocol's "qXfer:memory-map:read" packet, setting this variable
1751 lets GDB use hardware breakpoints automatically for memory regions
1752 where it can not use software breakpoints. This covers both the
1753 "break" command and internal breakpoints used for other commands
1754 including "next" and "finish".
1757 catch exception unhandled
1758 Stop the program execution when Ada exceptions are raised.
1761 Stop the program execution when an Ada assertion failed.
1765 Set an alternate system root for target files. This is a more
1766 general version of "set solib-absolute-prefix", which is now
1767 an alias to "set sysroot".
1770 Provide extended SPU facility status information. This set of
1771 commands is available only when debugging the Cell/B.E. SPU
1774 * New native configurations
1776 OpenBSD/sh sh*-*openbsd*
1779 unset tdesc filename
1781 Use the specified local file as an XML target description, and do
1782 not query the target for its built-in description.
1786 OpenBSD/sh sh*-*-openbsd*
1787 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1788 Toshiba Media Processor mep-elf
1790 * New remote packets
1793 Ignore the specified signals; pass them directly to the debugged program
1794 without stopping other threads or reporting them to GDB.
1796 qXfer:features:read:
1797 Read an XML target description from the target, which describes its
1802 Read or write contents of an spufs file on the target system. These
1803 packets are available only on the Cell/B.E. SPU architecture.
1805 qXfer:libraries:read:
1806 Report the loaded shared libraries. Combined with new "T" packet
1807 response, this packet allows GDB to debug shared libraries on
1808 targets where the operating system manages the list of loaded
1809 libraries (e.g. Windows and SymbianOS).
1813 Support for these obsolete configurations has been removed.
1821 i[34567]86-*-lynxos*
1822 i[34567]86-*-netware*
1823 i[34567]86-*-sco3.2v5*
1824 i[34567]86-*-sco3.2v4*
1826 i[34567]86-*-sysv4.2*
1829 i[34567]86-*-unixware2*
1830 i[34567]86-*-unixware*
1839 * Other removed features
1846 Various m68k-only ROM monitors.
1853 Various Renesas ROM monitors and debugging interfaces for SH and
1858 Support for a Macraigor serial interface to on-chip debugging.
1859 GDB does not directly support the newer parallel or USB
1864 A debug information format. The predecessor to DWARF 2 and
1865 DWARF 3, which are still supported.
1867 Support for the HP aCC compiler on HP-UX/PA-RISC
1869 SOM-encapsulated symbolic debugging information, automatic
1870 invocation of pxdb, and the aCC custom C++ ABI. This does not
1871 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1872 with aCC can still be debugged on an assembly level.
1874 MIPS ".pdr" sections
1876 A MIPS-specific format used to describe stack frame layout
1877 in debugging information.
1881 GDB could work with an older version of Guile to debug
1882 the interpreter and Scheme programs running in it.
1884 set mips stack-arg-size
1885 set mips saved-gpreg-size
1887 Use "set mips abi" to control parameter passing for MIPS.
1889 *** Changes in GDB 6.6
1894 Cell Broadband Engine SPU spu-elf
1896 * GDB can now be configured as a cross-debugger targeting native Windows
1897 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1898 running on a Windows system over TCP/IP to debug Windows programs.
1900 * The GDB remote stub, gdbserver, has been updated to support Windows and
1901 Cygwin debugging. Both single-threaded and multi-threaded programs are
1904 * The "set trust-readonly-sections" command works again. This command was
1905 broken in GDB 6.3, 6.4, and 6.5.
1907 * The "load" command now supports writing to flash memory, if the remote
1908 stub provides the required support.
1910 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1911 longer requires symbolic debug information (e.g. DWARF-2).
1916 unset substitute-path
1917 show substitute-path
1918 Manage a list of substitution rules that GDB uses to rewrite the name
1919 of the directories where the sources are located. This can be useful
1920 for instance when the sources were moved to a different location
1921 between compilation and debugging.
1925 Print each CLI command as it is executed. Each command is prefixed with
1926 a number of `+' symbols representing the nesting depth.
1927 The source command now has a `-v' option to enable the same feature.
1931 The ARM Demon monitor support (RDP protocol, "target rdp").
1933 Kernel Object Display, an embedded debugging feature which only worked with
1934 an obsolete version of Cisco IOS.
1936 The 'set download-write-size' and 'show download-write-size' commands.
1938 * New remote packets
1941 Tell a stub about GDB client features, and request remote target features.
1942 The first feature implemented is PacketSize, which allows the target to
1943 specify the size of packets it can handle - to minimize the number of
1944 packets required and improve performance when connected to a remote
1948 Fetch an OS auxilliary vector from the remote stub. This packet is a
1949 more efficient replacement for qPart:auxv:read.
1951 qXfer:memory-map:read:
1952 Fetch a memory map from the remote stub, including information about
1953 RAM, ROM, and flash memory devices.
1958 Erase and program a flash memory device.
1960 * Removed remote packets
1963 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1964 used it, and only gdbserver implemented it.
1966 *** Changes in GDB 6.5
1970 Renesas M32C/M16C m32c-elf
1972 Morpho Technologies ms1 ms1-elf
1976 init-if-undefined Initialize a convenience variable, but
1977 only if it doesn't already have a value.
1979 The following commands are presently only implemented for native GNU/Linux:
1981 checkpoint Save a snapshot of the program state.
1983 restart <n> Return the program state to a
1984 previously saved state.
1986 info checkpoints List currently saved checkpoints.
1988 delete-checkpoint <n> Delete a previously saved checkpoint.
1990 set|show detach-on-fork Tell gdb whether to detach from a newly
1991 forked process, or to keep debugging it.
1993 info forks List forks of the user program that
1994 are available to be debugged.
1996 fork <n> Switch to debugging one of several
1997 forks of the user program that are
1998 available to be debugged.
2000 delete-fork <n> Delete a fork from the list of forks
2001 that are available to be debugged (and
2002 kill the forked process).
2004 detach-fork <n> Delete a fork from the list of forks
2005 that are available to be debugged (and
2006 allow the process to continue).
2010 Morpho Technologies ms2 ms1-elf
2012 * Improved Windows host support
2014 GDB now builds as a cross debugger hosted on i686-mingw32, including
2015 native console support, and remote communications using either
2016 network sockets or serial ports.
2018 * Improved Modula-2 language support
2020 GDB can now print most types in the Modula-2 syntax. This includes:
2021 basic types, set types, record types, enumerated types, range types,
2022 pointer types and ARRAY types. Procedure var parameters are correctly
2023 printed and hexadecimal addresses and character constants are also
2024 written in the Modula-2 syntax. Best results can be obtained by using
2025 GNU Modula-2 together with the -gdwarf-2 command line option.
2029 The ARM rdi-share module.
2031 The Netware NLM debug server.
2033 *** Changes in GDB 6.4
2035 * New native configurations
2037 OpenBSD/arm arm*-*-openbsd*
2038 OpenBSD/mips64 mips64-*-openbsd*
2042 Morpho Technologies ms1 ms1-elf
2044 * New command line options
2046 --batch-silent As for --batch, but totally silent.
2047 --return-child-result The debugger will exist with the same value
2048 the child (debugged) program exited with.
2049 --eval-command COMMAND, -ex COMMAND
2050 Execute a single GDB CLI command. This may be
2051 specified multiple times and in conjunction
2052 with the --command (-x) option.
2054 * Deprecated commands removed
2056 The following commands, that were deprecated in 2000, have been
2060 set|show arm disassembly-flavor set|show arm disassembler
2061 othernames set arm disassembler
2062 set|show remotedebug set|show debug remote
2063 set|show archdebug set|show debug arch
2064 set|show eventdebug set|show debug event
2067 * New BSD user-level threads support
2069 It is now possible to debug programs using the user-level threads
2070 library on OpenBSD and FreeBSD. Currently supported (target)
2073 FreeBSD/amd64 x86_64-*-freebsd*
2074 FreeBSD/i386 i386-*-freebsd*
2075 OpenBSD/i386 i386-*-openbsd*
2077 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2078 are not yet supported.
2080 * New support for Matsushita MN10300 w/sim added
2081 (Work in progress). mn10300-elf.
2083 * REMOVED configurations and files
2085 VxWorks and the XDR protocol *-*-vxworks
2086 Motorola MCORE mcore-*-*
2087 National Semiconductor NS32000 ns32k-*-*
2089 * New "set print array-indexes" command
2091 After turning this setting "on", GDB prints the index of each element
2092 when displaying arrays. The default is "off" to preserve the previous
2095 * VAX floating point support
2097 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2099 * User-defined command support
2101 In addition to using $arg0..$arg9 for argument passing, it is now possible
2102 to use $argc to determine now many arguments have been passed. See the
2103 section on user-defined commands in the user manual for more information.
2105 *** Changes in GDB 6.3:
2107 * New command line option
2109 GDB now accepts -l followed by a number to set the timeout for remote
2112 * GDB works with GCC -feliminate-dwarf2-dups
2114 GDB now supports a more compact representation of DWARF-2 debug
2115 information using DW_FORM_ref_addr references. These are produced
2116 by GCC with the option -feliminate-dwarf2-dups and also by some
2117 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2118 to use -feliminate-dwarf2-dups.
2120 * Internationalization
2122 When supported by the host system, GDB will be built with
2123 internationalization (libintl). The task of marking up the sources is
2124 continued, we're looking forward to our first translation.
2128 Initial support for debugging programs compiled with the GNAT
2129 implementation of the Ada programming language has been integrated
2130 into GDB. In this release, support is limited to expression evaluation.
2132 * New native configurations
2134 GNU/Linux/m32r m32r-*-linux-gnu
2138 GDB's remote protocol now includes support for the 'p' packet. This
2139 packet is used to fetch individual registers from a remote inferior.
2141 * END-OF-LIFE registers[] compatibility module
2143 GDB's internal register infrastructure has been completely rewritten.
2144 The new infrastructure making possible the implementation of key new
2145 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2148 GDB 6.3 will be the last release to include the the registers[]
2149 compatibility module that allowed out-of-date configurations to
2150 continue to work. This change directly impacts the following
2160 powerpc bdm protocol
2162 Unless there is activity to revive these configurations, they will be
2163 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2165 * OBSOLETE configurations and files
2167 Configurations that have been declared obsolete in this release have
2168 been commented out. Unless there is activity to revive these
2169 configurations, the next release of GDB will have their sources
2170 permanently REMOVED.
2179 *** Changes in GDB 6.2.1:
2181 * MIPS `break main; run' gave an heuristic-fence-post warning
2183 When attempting to run even a simple program, a warning about
2184 heuristic-fence-post being hit would be reported. This problem has
2187 * MIPS IRIX 'long double' crashed GDB
2189 When examining a long double variable, GDB would get a segmentation
2190 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2191 IRIX long double values).
2195 A bug in the VAX stack code was causing problems with the "next"
2196 command. This problem has been fixed.
2198 *** Changes in GDB 6.2:
2200 * Fix for ``many threads''
2202 On GNU/Linux systems that use the NPTL threads library, a program
2203 rapidly creating and deleting threads would confuse GDB leading to the
2206 ptrace: No such process.
2207 thread_db_get_info: cannot get thread info: generic error
2209 This problem has been fixed.
2211 * "-async" and "-noasync" options removed.
2213 Support for the broken "-noasync" option has been removed (it caused
2216 * New ``start'' command.
2218 This command runs the program until the begining of the main procedure.
2220 * New BSD Kernel Data Access Library (libkvm) interface
2222 Using ``target kvm'' it is now possible to debug kernel core dumps and
2223 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2224 platforms. Currently supported (native-only) configurations are:
2226 FreeBSD/amd64 x86_64-*-freebsd*
2227 FreeBSD/i386 i?86-*-freebsd*
2228 NetBSD/i386 i?86-*-netbsd*
2229 NetBSD/m68k m68*-*-netbsd*
2230 NetBSD/sparc sparc-*-netbsd*
2231 OpenBSD/amd64 x86_64-*-openbsd*
2232 OpenBSD/i386 i?86-*-openbsd*
2233 OpenBSD/m68k m68*-openbsd*
2234 OpenBSD/sparc sparc-*-openbsd*
2236 * Signal trampoline code overhauled
2238 Many generic problems with GDB's signal handling code have been fixed.
2239 These include: backtraces through non-contiguous stacks; recognition
2240 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2241 call; backtrace through a signal trampoline; step into and out of
2242 signal handlers; and single-stepping in the signal trampoline.
2244 Please note that kernel bugs are a limiting factor here. These
2245 features have been shown to work on an s390 GNU/Linux system that
2246 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2248 * Cygwin support for DWARF 2 added.
2250 * New native configurations
2252 GNU/Linux/hppa hppa*-*-linux*
2253 OpenBSD/hppa hppa*-*-openbsd*
2254 OpenBSD/m68k m68*-*-openbsd*
2255 OpenBSD/m88k m88*-*-openbsd*
2256 OpenBSD/powerpc powerpc-*-openbsd*
2257 NetBSD/vax vax-*-netbsd*
2258 OpenBSD/vax vax-*-openbsd*
2260 * END-OF-LIFE frame compatibility module
2262 GDB's internal frame infrastructure has been completely rewritten.
2263 The new infrastructure making it possible to support key new features
2264 including DWARF 2 Call Frame Information. To aid in the task of
2265 migrating old configurations to this new infrastructure, a
2266 compatibility module, that allowed old configurations to continue to
2267 work, was also included.
2269 GDB 6.2 will be the last release to include this frame compatibility
2270 module. This change directly impacts the following configurations:
2280 Unless there is activity to revive these configurations, they will be
2281 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2283 * REMOVED configurations and files
2285 Sun 3, running SunOS 3 m68*-*-sunos3*
2286 Sun 3, running SunOS 4 m68*-*-sunos4*
2287 Sun 2, running SunOS 3 m68000-*-sunos3*
2288 Sun 2, running SunOS 4 m68000-*-sunos4*
2289 Motorola 680x0 running LynxOS m68*-*-lynxos*
2290 AT&T 3b1/Unix pc m68*-att-*
2291 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2292 decstation mips-dec-* mips-little-*
2293 riscos mips-*-riscos* mips-*-sysv*
2294 sonymips mips-sony-*
2295 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2297 *** Changes in GDB 6.1.1:
2299 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2301 The TUI (Text-mode User Interface) is now built as part of a default
2302 GDB configuration. It is enabled by either selecting the TUI with the
2303 command line option "-i=tui" or by running the separate "gdbtui"
2304 program. For more information on the TUI, see the manual "Debugging
2307 * Pending breakpoint support (also included in GDB 6.1)
2309 Support has been added to allow you to specify breakpoints in shared
2310 libraries that have not yet been loaded. If a breakpoint location
2311 cannot be found, and the "breakpoint pending" option is set to auto,
2312 GDB queries you if you wish to make the breakpoint pending on a future
2313 shared-library load. If and when GDB resolves the breakpoint symbol,
2314 the pending breakpoint is removed as one or more regular breakpoints
2317 Pending breakpoints are very useful for GCJ Java debugging.
2319 * Fixed ISO-C build problems
2321 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2322 non ISO-C code that stopped them being built using a more strict ISO-C
2323 compiler (e.g., IBM's C compiler).
2325 * Fixed build problem on IRIX 5
2327 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2328 wasn't able to compile compile on an IRIX 5 system.
2330 * Added execute permission to gdb/gdbserver/configure
2332 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2333 permission. This bug would cause configure to fail on a number of
2334 systems (Solaris, IRIX). Ref: server/519.
2336 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2338 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2339 has been updated to use constant array sizes.
2341 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2343 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2344 its generated DWARF Call Frame Info. This encoding was causing GDB to
2345 panic, that panic has been fixed. Ref: gdb/1628.
2347 * Fixed a problem when examining parameters in shared library code.
2349 When examining parameters in optimized shared library code generated
2350 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2351 not available''. GDB now correctly displays the variable's value.
2353 *** Changes in GDB 6.1:
2355 * Removed --with-mmalloc
2357 Support for the mmalloc memory manager has been removed, as it
2358 conflicted with the internal gdb byte cache.
2360 * Changes in AMD64 configurations
2362 The AMD64 target now includes the %cs and %ss registers. As a result
2363 the AMD64 remote protocol has changed; this affects the floating-point
2364 and SSE registers. If you rely on those registers for your debugging,
2365 you should upgrade gdbserver on the remote side.
2367 * Revised SPARC target
2369 The SPARC target has been completely revised, incorporating the
2370 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2371 support for LynxOS and SunOS 4 has been dropped. Calling functions
2372 from within GDB on operating systems with a non-executable stack
2373 (Solaris, OpenBSD) now works.
2377 GDB has a new C++ demangler which does a better job on the mangled
2378 names generated by current versions of g++. It also runs faster, so
2379 with this and other changes gdb should now start faster on large C++
2382 * DWARF 2 Location Expressions
2384 GDB support for location expressions has been extended to support function
2385 arguments and frame bases. Older versions of GDB could crash when they
2388 * C++ nested types and namespaces
2390 GDB's support for nested types and namespaces in C++ has been
2391 improved, especially if you use the DWARF 2 debugging format. (This
2392 is the default for recent versions of GCC on most platforms.)
2393 Specifically, if you have a class "Inner" defined within a class or
2394 namespace "Outer", then GDB realizes that the class's name is
2395 "Outer::Inner", not simply "Inner". This should greatly reduce the
2396 frequency of complaints about not finding RTTI symbols. In addition,
2397 if you are stopped at inside of a function defined within a namespace,
2398 GDB modifies its name lookup accordingly.
2400 * New native configurations
2402 NetBSD/amd64 x86_64-*-netbsd*
2403 OpenBSD/amd64 x86_64-*-openbsd*
2404 OpenBSD/alpha alpha*-*-openbsd*
2405 OpenBSD/sparc sparc-*-openbsd*
2406 OpenBSD/sparc64 sparc64-*-openbsd*
2408 * New debugging protocols
2410 M32R with SDI protocol m32r-*-elf*
2412 * "set prompt-escape-char" command deleted.
2414 The command "set prompt-escape-char" has been deleted. This command,
2415 and its very obscure effet on GDB's prompt, was never documented,
2416 tested, nor mentioned in the NEWS file.
2418 * OBSOLETE configurations and files
2420 Configurations that have been declared obsolete in this release have
2421 been commented out. Unless there is activity to revive these
2422 configurations, the next release of GDB will have their sources
2423 permanently REMOVED.
2425 Sun 3, running SunOS 3 m68*-*-sunos3*
2426 Sun 3, running SunOS 4 m68*-*-sunos4*
2427 Sun 2, running SunOS 3 m68000-*-sunos3*
2428 Sun 2, running SunOS 4 m68000-*-sunos4*
2429 Motorola 680x0 running LynxOS m68*-*-lynxos*
2430 AT&T 3b1/Unix pc m68*-att-*
2431 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2432 decstation mips-dec-* mips-little-*
2433 riscos mips-*-riscos* mips-*-sysv*
2434 sonymips mips-sony-*
2435 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2437 * REMOVED configurations and files
2439 SGI Irix-4.x mips-sgi-irix4 or iris4
2440 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2441 Z8000 simulator z8k-zilog-none or z8ksim
2442 Matsushita MN10200 w/simulator mn10200-*-*
2443 H8/500 simulator h8500-hitachi-hms or h8500hms
2444 HP/PA running BSD hppa*-*-bsd*
2445 HP/PA running OSF/1 hppa*-*-osf*
2446 HP/PA Pro target hppa*-*-pro*
2447 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2448 386BSD i[3456]86-*-bsd*
2449 Sequent family i[3456]86-sequent-sysv4*
2450 i[3456]86-sequent-sysv*
2451 i[3456]86-sequent-bsd*
2452 SPARC running LynxOS sparc-*-lynxos*
2453 SPARC running SunOS 4 sparc-*-sunos4*
2454 Tsqware Sparclet sparclet-*-*
2455 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2457 *** Changes in GDB 6.0:
2461 Support for debugging the Objective-C programming language has been
2462 integrated into GDB.
2464 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2466 DWARF 2's Call Frame Information makes available compiler generated
2467 information that more exactly describes the program's run-time stack.
2468 By using this information, GDB is able to provide more robust stack
2471 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2472 have been updated to use a new backtrace mechanism which includes
2473 DWARF 2 CFI support.
2477 GDB's remote protocol has been extended to include support for hosted
2478 file I/O (where the remote target uses GDB's file system). See GDB's
2479 remote protocol documentation for details.
2481 * All targets using the new architecture framework.
2483 All of GDB's targets have been updated to use the new internal
2484 architecture framework. The way is now open for future GDB releases
2485 to include cross-architecture native debugging support (i386 on amd64,
2488 * GNU/Linux's Thread Local Storage (TLS)
2490 GDB now includes support for for the GNU/Linux implementation of
2491 per-thread variables.
2493 * GNU/Linux's Native POSIX Thread Library (NPTL)
2495 GDB's thread code has been updated to work with either the new
2496 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2498 * Separate debug info.
2500 GDB, in conjunction with BINUTILS, now supports a mechanism for
2501 automatically loading debug information from a separate file. Instead
2502 of shipping full debug and non-debug versions of system libraries,
2503 system integrators can now instead ship just the stripped libraries
2504 and optional debug files.
2506 * DWARF 2 Location Expressions
2508 DWARF 2 Location Expressions allow the compiler to more completely
2509 describe the location of variables (even in optimized code) to the
2512 GDB now includes preliminary support for location expressions (support
2513 for DW_OP_piece is still missing).
2517 A number of long standing bugs that caused GDB to die while starting a
2518 Java application have been fixed. GDB's Java support is now
2519 considered "useable".
2521 * GNU/Linux support for fork, vfork, and exec.
2523 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2524 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2527 * GDB supports logging output to a file
2529 There are two new commands, "set logging" and "show logging", which can be
2530 used to capture GDB's output to a file.
2532 * The meaning of "detach" has changed for gdbserver
2534 The "detach" command will now resume the application, as documented. To
2535 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2538 * d10v, m68hc11 `regs' command deprecated
2540 The `info registers' command has been updated so that it displays the
2541 registers using a format identical to the old `regs' command.
2545 A new command, "maint set profile on/off", has been added. This command can
2546 be used to enable or disable profiling while running GDB, to profile a
2547 session or a set of commands. In addition there is a new configure switch,
2548 "--enable-profiling", which will cause GDB to be compiled with profiling
2549 data, for more informative profiling results.
2551 * Default MI syntax changed to "mi2".
2553 The default MI (machine interface) syntax, enabled by the command line
2554 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2555 "mi1", can be enabled by specifying the option "-i=mi1".
2557 Support for the original "mi0" syntax (included in GDB 5.0) has been
2560 Fix for gdb/192: removed extraneous space when displaying frame level.
2561 Fix for gdb/672: update changelist is now output in mi list format.
2562 Fix for gdb/702: a -var-assign that updates the value now shows up
2563 in a subsequent -var-update.
2565 * New native configurations.
2567 FreeBSD/amd64 x86_64-*-freebsd*
2569 * Multi-arched targets.
2571 HP/PA HPUX11 hppa*-*-hpux*
2572 Renesas M32R/D w/simulator m32r-*-elf*
2574 * OBSOLETE configurations and files
2576 Configurations that have been declared obsolete in this release have
2577 been commented out. Unless there is activity to revive these
2578 configurations, the next release of GDB will have their sources
2579 permanently REMOVED.
2581 Z8000 simulator z8k-zilog-none or z8ksim
2582 Matsushita MN10200 w/simulator mn10200-*-*
2583 H8/500 simulator h8500-hitachi-hms or h8500hms
2584 HP/PA running BSD hppa*-*-bsd*
2585 HP/PA running OSF/1 hppa*-*-osf*
2586 HP/PA Pro target hppa*-*-pro*
2587 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2588 Sequent family i[3456]86-sequent-sysv4*
2589 i[3456]86-sequent-sysv*
2590 i[3456]86-sequent-bsd*
2591 Tsqware Sparclet sparclet-*-*
2592 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2594 * REMOVED configurations and files
2597 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2598 IBM AIX PS/2 i[3456]86-*-aix
2599 i386 running Mach 3.0 i[3456]86-*-mach3*
2600 i386 running Mach i[3456]86-*-mach*
2601 i386 running OSF/1 i[3456]86-*osf1mk*
2602 HP/Apollo 68k Family m68*-apollo*-sysv*,
2604 m68*-hp-bsd*, m68*-hp-hpux*
2605 Argonaut Risc Chip (ARC) arc-*-*
2606 Mitsubishi D30V d30v-*-*
2607 Fujitsu FR30 fr30-*-elf*
2608 OS/9000 i[34]86-*-os9k
2609 I960 with MON960 i960-*-coff
2611 * MIPS $fp behavior changed
2613 The convenience variable $fp, for the MIPS, now consistently returns
2614 the address of the current frame's base. Previously, depending on the
2615 context, $fp could refer to either $sp or the current frame's base
2616 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2617 The GNU Source-Level Debugger''.
2619 *** Changes in GDB 5.3:
2621 * GNU/Linux shared library multi-threaded performance improved.
2623 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2624 `/proc', in preference to `ptrace' for memory reads. This may result
2625 in an improvement in the start-up time of multi-threaded, shared
2626 library applications when run under GDB. One GDB user writes: ``loads
2627 shared libs like mad''.
2629 * ``gdbserver'' now supports multi-threaded applications on some targets
2631 Support for debugging multi-threaded applications which use
2632 the GNU/Linux LinuxThreads package has been added for
2633 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2634 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2636 * GDB now supports C/C++ preprocessor macros.
2638 GDB now expands preprocessor macro invocations in C/C++ expressions,
2639 and provides various commands for showing macro definitions and how
2642 The new command `macro expand EXPRESSION' expands any macro
2643 invocations in expression, and shows the result.
2645 The new command `show macro MACRO-NAME' shows the definition of the
2646 macro named MACRO-NAME, and where it was defined.
2648 Most compilers don't include information about macros in the debugging
2649 information by default. In GCC 3.1, for example, you need to compile
2650 your program with the options `-gdwarf-2 -g3'. If the macro
2651 information is present in the executable, GDB will read it.
2653 * Multi-arched targets.
2655 DEC Alpha (partial) alpha*-*-*
2656 DEC VAX (partial) vax-*-*
2658 National Semiconductor NS32000 (partial) ns32k-*-*
2659 Motorola 68000 (partial) m68k-*-*
2660 Motorola MCORE mcore-*-*
2664 Fujitsu FRV architecture added by Red Hat frv*-*-*
2667 * New native configurations
2669 Alpha NetBSD alpha*-*-netbsd*
2670 SH NetBSD sh*-*-netbsdelf*
2671 MIPS NetBSD mips*-*-netbsd*
2672 UltraSPARC NetBSD sparc64-*-netbsd*
2674 * OBSOLETE configurations and files
2676 Configurations that have been declared obsolete in this release have
2677 been commented out. Unless there is activity to revive these
2678 configurations, the next release of GDB will have their sources
2679 permanently REMOVED.
2681 Mitsubishi D30V d30v-*-*
2682 OS/9000 i[34]86-*-os9k
2683 IBM AIX PS/2 i[3456]86-*-aix
2684 Fujitsu FR30 fr30-*-elf*
2685 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2686 Argonaut Risc Chip (ARC) arc-*-*
2687 i386 running Mach 3.0 i[3456]86-*-mach3*
2688 i386 running Mach i[3456]86-*-mach*
2689 i386 running OSF/1 i[3456]86-*osf1mk*
2690 HP/Apollo 68k Family m68*-apollo*-sysv*,
2692 m68*-hp-bsd*, m68*-hp-hpux*
2693 I960 with MON960 i960-*-coff
2695 * OBSOLETE languages
2697 CHILL, a Pascal like language used by telecommunications companies.
2699 * REMOVED configurations and files
2701 AMD 29k family via UDI a29k-amd-udi, udi29k
2702 A29K VxWorks a29k-*-vxworks
2703 AMD 29000 embedded, using EBMON a29k-none-none
2704 AMD 29000 embedded with COFF a29k-none-coff
2705 AMD 29000 embedded with a.out a29k-none-aout
2707 testsuite/gdb.hp/gdb.threads-hp/ directory
2709 * New command "set max-user-call-depth <nnn>"
2711 This command allows the user to limit the call depth of user-defined
2712 commands. The default is 1024.
2714 * Changes in FreeBSD/i386 native debugging.
2716 Support for the "generate-core-file" has been added.
2718 * New commands "dump", "append", and "restore".
2720 These commands allow data to be copied from target memory
2721 to a bfd-format or binary file (dump and append), and back
2722 from a file into memory (restore).
2724 * Improved "next/step" support on multi-processor Alpha Tru64.
2726 The previous single-step mechanism could cause unpredictable problems,
2727 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2728 of a software single-step mechanism prevents this.
2730 *** Changes in GDB 5.2.1:
2738 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2739 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2740 Fix, by Joel Brobecker imported from mainline.
2742 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2743 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2744 Fix, by Fred Fish, imported from mainline.
2746 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2747 Surprisingly enough, it works now.
2748 By Michal Ludvig, imported from mainline.
2750 i386 hardware watchpoint support:
2751 avoid misses on second run for some targets.
2752 By Pierre Muller, imported from mainline.
2754 *** Changes in GDB 5.2:
2756 * New command "set trust-readonly-sections on[off]".
2758 This command is a hint that tells gdb that read-only sections
2759 really are read-only (ie. that their contents will not change).
2760 In this mode, gdb will go to the object file rather than the
2761 target to read memory from read-only sections (such as ".text").
2762 This can be a significant performance improvement on some
2763 (notably embedded) targets.
2765 * New command "generate-core-file" (or "gcore").
2767 This new gdb command allows the user to drop a core file of the child
2768 process state at any time. So far it's been implemented only for
2769 GNU/Linux and Solaris, but should be relatively easily ported to other
2770 hosts. Argument is core file name (defaults to core.<pid>).
2772 * New command line option
2774 GDB now accepts --pid or -p followed by a process id.
2776 * Change in command line behavior -- corefiles vs. process ids.
2778 There is a subtle behavior in the way in which GDB handles
2779 command line arguments. The first non-flag argument is always
2780 a program to debug, but the second non-flag argument may either
2781 be a corefile or a process id. Previously, GDB would attempt to
2782 open the second argument as a corefile, and if that failed, would
2783 issue a superfluous error message and then attempt to attach it as
2784 a process. Now, if the second argument begins with a non-digit,
2785 it will be treated as a corefile. If it begins with a digit,
2786 GDB will attempt to attach it as a process, and if no such process
2787 is found, will then attempt to open it as a corefile.
2789 * Changes in ARM configurations.
2791 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2792 configuration is fully multi-arch.
2794 * New native configurations
2796 ARM NetBSD arm*-*-netbsd*
2797 x86 OpenBSD i[3456]86-*-openbsd*
2798 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2799 Sparc64 running FreeBSD sparc64-*-freebsd*
2803 Sanyo XStormy16 xstormy16-elf
2805 * OBSOLETE configurations and files
2807 Configurations that have been declared obsolete in this release have
2808 been commented out. Unless there is activity to revive these
2809 configurations, the next release of GDB will have their sources
2810 permanently REMOVED.
2812 AMD 29k family via UDI a29k-amd-udi, udi29k
2813 A29K VxWorks a29k-*-vxworks
2814 AMD 29000 embedded, using EBMON a29k-none-none
2815 AMD 29000 embedded with COFF a29k-none-coff
2816 AMD 29000 embedded with a.out a29k-none-aout
2818 testsuite/gdb.hp/gdb.threads-hp/ directory
2820 * REMOVED configurations and files
2822 TI TMS320C80 tic80-*-*
2824 PowerPC Solaris powerpcle-*-solaris*
2825 PowerPC Windows NT powerpcle-*-cygwin32
2826 PowerPC Netware powerpc-*-netware*
2827 Harris/CXUX m88k m88*-harris-cxux*
2828 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2829 ns32k-utek-sysv* ns32k-utek-*
2830 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2831 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2832 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2833 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2834 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2836 * Changes to command line processing
2838 The new `--args' feature can be used to specify command-line arguments
2839 for the inferior from gdb's command line.
2841 * Changes to key bindings
2843 There is a new `operate-and-get-next' function bound to `C-o'.
2845 *** Changes in GDB 5.1.1
2847 Fix compile problem on DJGPP.
2849 Fix a problem with floating-point registers on the i386 being
2852 Fix to stop GDB crashing on .debug_str debug info.
2854 Numerous documentation fixes.
2856 Numerous testsuite fixes.
2858 *** Changes in GDB 5.1:
2860 * New native configurations
2862 Alpha FreeBSD alpha*-*-freebsd*
2863 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2864 MIPS GNU/Linux mips*-*-linux*
2865 MIPS SGI Irix 6.x mips*-sgi-irix6*
2866 ia64 AIX ia64-*-aix*
2867 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2871 Motorola 68HC11 and 68HC12 m68hc11-elf
2873 UltraSparc running GNU/Linux sparc64-*-linux*
2875 * OBSOLETE configurations and files
2877 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2878 Harris/CXUX m88k m88*-harris-cxux*
2879 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2880 ns32k-utek-sysv* ns32k-utek-*
2881 TI TMS320C80 tic80-*-*
2883 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2884 PowerPC Solaris powerpcle-*-solaris*
2885 PowerPC Windows NT powerpcle-*-cygwin32
2886 PowerPC Netware powerpc-*-netware*
2887 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2888 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2889 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2890 Apple Macintosh (MPW) host N/A
2892 stuff.c (Program to stuff files into a specially prepared space in kdb)
2893 kdb-start.c (Main loop for the standalone kernel debugger)
2895 Configurations that have been declared obsolete in this release have
2896 been commented out. Unless there is activity to revive these
2897 configurations, the next release of GDB will have their sources
2898 permanently REMOVED.
2900 * REMOVED configurations and files
2902 Altos 3068 m68*-altos-*
2903 Convex c1-*-*, c2-*-*
2905 ARM RISCix arm-*-* (as host)
2909 * GDB has been converted to ISO C.
2911 GDB's source code has been converted to ISO C. In particular, the
2912 sources are fully protoized, and rely on standard headers being
2917 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2919 * The MI enabled by default.
2921 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2922 revised and enabled by default. Packages which use GDB as a debugging
2923 engine behind a UI or another front end are encouraged to switch to
2924 using the GDB/MI interface, instead of the old annotations interface
2925 which is now deprecated.
2927 * Support for debugging Pascal programs.
2929 GDB now includes support for debugging Pascal programs. The following
2930 main features are supported:
2932 - Pascal-specific data types such as sets;
2934 - automatic recognition of Pascal sources based on file-name
2937 - Pascal-style display of data types, variables, and functions;
2939 - a Pascal expression parser.
2941 However, some important features are not yet supported.
2943 - Pascal string operations are not supported at all;
2945 - there are some problems with boolean types;
2947 - Pascal type hexadecimal constants are not supported
2948 because they conflict with the internal variables format;
2950 - support for Pascal objects and classes is not full yet;
2952 - unlike Pascal, GDB is case-sensitive for symbol names.
2954 * Changes in completion.
2956 Commands such as `shell', `run' and `set args', which pass arguments
2957 to inferior programs, now complete on file names, similar to what
2958 users expect at the shell prompt.
2960 Commands which accept locations, such as `disassemble', `print',
2961 `breakpoint', `until', etc. now complete on filenames as well as
2962 program symbols. Thus, if you type "break foob TAB", and the source
2963 files linked into the programs include `foobar.c', that file name will
2964 be one of the candidates for completion. However, file names are not
2965 considered for completion after you typed a colon that delimits a file
2966 name from a name of a function in that file, as in "break foo.c:bar".
2968 `set demangle-style' completes on available demangling styles.
2970 * New platform-independent commands:
2972 It is now possible to define a post-hook for a command as well as a
2973 hook that runs before the command. For more details, see the
2974 documentation of `hookpost' in the GDB manual.
2976 * Changes in GNU/Linux native debugging.
2978 Support for debugging multi-threaded programs has been completely
2979 revised for all platforms except m68k and sparc. You can now debug as
2980 many threads as your system allows you to have.
2982 Attach/detach is supported for multi-threaded programs.
2984 Support for SSE registers was added for x86. This doesn't work for
2985 multi-threaded programs though.
2987 * Changes in MIPS configurations.
2989 Multi-arch support is enabled for all MIPS configurations.
2991 GDB can now be built as native debugger on SGI Irix 6.x systems for
2992 debugging n32 executables. (Debugging 64-bit executables is not yet
2995 * Unified support for hardware watchpoints in all x86 configurations.
2997 Most (if not all) native x86 configurations support hardware-assisted
2998 breakpoints and watchpoints in a unified manner. This support
2999 implements debug register sharing between watchpoints, which allows to
3000 put a virtually infinite number of watchpoints on the same address,
3001 and also supports watching regions up to 16 bytes with several debug
3004 The new maintenance command `maintenance show-debug-regs' toggles
3005 debugging print-outs in functions that insert, remove, and test
3006 watchpoints and hardware breakpoints.
3008 * Changes in the DJGPP native configuration.
3010 New command ``info dos sysinfo'' displays assorted information about
3011 the CPU, OS, memory, and DPMI server.
3013 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3014 display information about segment descriptors stored in GDT, LDT, and
3017 New commands ``info dos pde'' and ``info dos pte'' display entries
3018 from Page Directory and Page Tables (for now works with CWSDPMI only).
3019 New command ``info dos address-pte'' displays the Page Table entry for
3020 a given linear address.
3022 GDB can now pass command lines longer than 126 characters to the
3023 program being debugged (requires an update to the libdbg.a library
3024 which is part of the DJGPP development kit).
3026 DWARF2 debug info is now supported.
3028 It is now possible to `step' and `next' through calls to `longjmp'.
3030 * Changes in documentation.
3032 All GDB documentation was converted to GFDL, the GNU Free
3033 Documentation License.
3035 Tracepoints-related commands are now fully documented in the GDB
3038 TUI, the Text-mode User Interface, is now documented in the manual.
3040 Tracepoints-related commands are now fully documented in the GDB
3043 The "GDB Internals" manual now has an index. It also includes
3044 documentation of `ui_out' functions, GDB coding standards, x86
3045 hardware watchpoints, and memory region attributes.
3047 * GDB's version number moved to ``version.in''
3049 The Makefile variable VERSION has been replaced by the file
3050 ``version.in''. People creating GDB distributions should update the
3051 contents of this file.
3055 GUD support is now a standard part of the EMACS distribution.
3057 *** Changes in GDB 5.0:
3059 * Improved support for debugging FP programs on x86 targets
3061 Unified and much-improved support for debugging floating-point
3062 programs on all x86 targets. In particular, ``info float'' now
3063 displays the FP registers in the same format on all x86 targets, with
3064 greater level of detail.
3066 * Improvements and bugfixes in hardware-assisted watchpoints
3068 It is now possible to watch array elements, struct members, and
3069 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3070 on x86 targets no longer erroneously trigger when the address is
3073 * Improvements in the native DJGPP version of GDB
3075 The distribution now includes all the scripts and auxiliary files
3076 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3077 machines ``out of the box''.
3079 The DJGPP version can now debug programs that use signals. It is
3080 possible to catch signals that happened in the debuggee, deliver
3081 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3082 would kill the program being debugged.) Programs that hook hardware
3083 interrupts (keyboard, timer, etc.) can also be debugged.
3085 It is now possible to debug DJGPP programs that redirect their
3086 standard handles or switch them to raw (as opposed to cooked) mode, or
3087 even close them. The command ``run < foo > bar'' works as expected,
3088 and ``info terminal'' reports useful information about the debuggee's
3089 terminal, including raw/cooked mode, redirection, etc.
3091 The DJGPP version now uses termios functions for console I/O, which
3092 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3095 DOS-style file names with drive letters are now fully supported by
3098 It is now possible to debug DJGPP programs that switch their working
3099 directory. It is also possible to rerun the debuggee any number of
3100 times without restarting GDB; thus, you can use the same setup,
3101 breakpoints, etc. for many debugging sessions.
3103 * New native configurations
3105 ARM GNU/Linux arm*-*-linux*
3106 PowerPC GNU/Linux powerpc-*-linux*
3110 Motorola MCore mcore-*-*
3111 x86 VxWorks i[3456]86-*-vxworks*
3112 PowerPC VxWorks powerpc-*-vxworks*
3113 TI TMS320C80 tic80-*-*
3115 * OBSOLETE configurations
3117 Altos 3068 m68*-altos-*
3118 Convex c1-*-*, c2-*-*
3120 ARM RISCix arm-*-* (as host)
3123 Configurations that have been declared obsolete will be commented out,
3124 but the code will be left in place. If there is no activity to revive
3125 these configurations before the next release of GDB, the sources will
3126 be permanently REMOVED.
3128 * Gould support removed
3130 Support for the Gould PowerNode and NP1 has been removed.
3132 * New features for SVR4
3134 On SVR4 native platforms (such as Solaris), if you attach to a process
3135 without first loading a symbol file, GDB will now attempt to locate and
3136 load symbols from the running process's executable file.
3138 * Many C++ enhancements
3140 C++ support has been greatly improved. Overload resolution now works properly
3141 in almost all cases. RTTI support is on the way.
3143 * Remote targets can connect to a sub-program
3145 A popen(3) style serial-device has been added. This device starts a
3146 sub-process (such as a stand-alone simulator) and then communicates
3147 with that. The sub-program to run is specified using the syntax
3148 ``|<program> <args>'' vis:
3150 (gdb) set remotedebug 1
3151 (gdb) target extended-remote |mn10300-elf-sim program-args
3153 * MIPS 64 remote protocol
3155 A long standing bug in the mips64 remote protocol where by GDB
3156 expected certain 32 bit registers (ex SR) to be transfered as 32
3157 instead of 64 bits has been fixed.
3159 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3160 added to provide backward compatibility with older versions of GDB.
3162 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3164 The command ``set remotebinarydownload'' command has been replaced by
3165 ``set remote X-packet''. Other commands in ``set remote'' family
3166 include ``set remote P-packet''.
3168 * Breakpoint commands accept ranges.
3170 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3171 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3172 ``tracepoint passcount'' also accepts a range of tracepoints.
3174 * ``apropos'' command added.
3176 The ``apropos'' command searches through command names and
3177 documentation strings, printing out matches, making it much easier to
3178 try to find a command that does what you are looking for.
3182 A new machine oriented interface (MI) has been added to GDB. This
3183 interface is designed for debug environments running GDB as a separate
3184 process. This is part of the long term libGDB project. See the
3185 "GDB/MI" chapter of the GDB manual for further information. It can be
3186 enabled by configuring with:
3188 .../configure --enable-gdbmi
3190 *** Changes in GDB-4.18:
3192 * New native configurations
3194 HP-UX 10.20 hppa*-*-hpux10.20
3195 HP-UX 11.x hppa*-*-hpux11.0*
3196 M68K GNU/Linux m68*-*-linux*
3200 Fujitsu FR30 fr30-*-elf*
3201 Intel StrongARM strongarm-*-*
3202 Mitsubishi D30V d30v-*-*
3204 * OBSOLETE configurations
3206 Gould PowerNode, NP1 np1-*-*, pn-*-*
3208 Configurations that have been declared obsolete will be commented out,
3209 but the code will be left in place. If there is no activity to revive
3210 these configurations before the next release of GDB, the sources will
3211 be permanently REMOVED.
3215 As a compatibility experiment, GDB's source files buildsym.h and
3216 buildsym.c have been converted to pure standard C, no longer
3217 containing any K&R compatibility code. We believe that all systems in
3218 use today either come with a standard C compiler, or have a GCC port
3219 available. If this is not true, please report the affected
3220 configuration to bug-gdb@gnu.org immediately. See the README file for
3221 information about getting a standard C compiler if you don't have one
3226 GDB now uses readline 2.2.
3228 * set extension-language
3230 You can now control the mapping between filename extensions and source
3231 languages by using the `set extension-language' command. For instance,
3232 you can ask GDB to treat .c files as C++ by saying
3233 set extension-language .c c++
3234 The command `info extensions' lists all of the recognized extensions
3235 and their associated languages.
3237 * Setting processor type for PowerPC and RS/6000
3239 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3240 you can use the `set processor' command to specify what variant of the
3241 PowerPC family you are debugging. The command
3245 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3246 following PowerPC and RS6000 variants:
3248 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3249 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3251 403GC IBM PowerPC 403GC
3252 505 Motorola PowerPC 505
3253 860 Motorola PowerPC 860 or 850
3254 601 Motorola PowerPC 601
3255 602 Motorola PowerPC 602
3256 603 Motorola/IBM PowerPC 603 or 603e
3257 604 Motorola PowerPC 604 or 604e
3258 750 Motorola/IBM PowerPC 750 or 750
3260 At the moment, this command just tells GDB what to name the
3261 special-purpose processor registers. Since almost all the affected
3262 registers are inaccessible to user-level programs, this command is
3263 only useful for remote debugging in its present form.
3267 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3268 more extensive support for HP-UX. Added features include shared
3269 library support, kernel threads and hardware watchpoints for 11.00,
3270 support for HP's ANSI C and C++ compilers, and a compatibility mode
3271 for xdb and dbx commands.
3275 HP's donation includes the new concept of catchpoints, which is a
3276 generalization of the old catch command. On HP-UX, it is now possible
3277 to catch exec, fork, and vfork, as well as library loading.
3279 This means that the existing catch command has changed; its first
3280 argument now specifies the type of catch to be set up. See the
3281 output of "help catch" for a list of catchpoint types.
3283 * Debugging across forks
3285 On HP-UX, you can choose which process to debug when a fork() happens
3290 HP has donated a curses-based terminal user interface (TUI). To get
3291 it, build with --enable-tui. Although this can be enabled for any
3292 configuration, at present it only works for native HP debugging.
3294 * GDB remote protocol additions
3296 A new protocol packet 'X' that writes binary data is now available.
3297 Default behavior is to try 'X', then drop back to 'M' if the stub
3298 fails to respond. The settable variable `remotebinarydownload'
3299 allows explicit control over the use of 'X'.
3301 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3302 full 64-bit address. The command
3304 set remoteaddresssize 32
3306 can be used to revert to the old behaviour. For existing remote stubs
3307 the change should not be noticed, as the additional address information
3310 In order to assist in debugging stubs, you may use the maintenance
3311 command `packet' to send any text string to the stub. For instance,
3313 maint packet heythere
3315 sends the packet "$heythere#<checksum>". Note that it is very easy to
3316 disrupt a debugging session by sending the wrong packet at the wrong
3319 The compare-sections command allows you to compare section data on the
3320 target to what is in the executable file without uploading or
3321 downloading, by comparing CRC checksums.
3323 * Tracing can collect general expressions
3325 You may now collect general expressions at tracepoints. This requires
3326 further additions to the target-side stub; see tracepoint.c and
3327 doc/agentexpr.texi for further details.
3329 * mask-address variable for Mips
3331 For Mips targets, you may control the zeroing of the upper 32 bits of
3332 a 64-bit address by entering `set mask-address on'. This is mainly
3333 of interest to users of embedded R4xxx and R5xxx processors.
3335 * Higher serial baud rates
3337 GDB's serial code now allows you to specify baud rates 57600, 115200,
3338 230400, and 460800 baud. (Note that your host system may not be able
3339 to achieve all of these rates.)
3343 The i960 configuration now includes an initial implementation of a
3344 builtin simulator, contributed by Jim Wilson.
3347 *** Changes in GDB-4.17:
3349 * New native configurations
3351 Alpha GNU/Linux alpha*-*-linux*
3352 Unixware 2.x i[3456]86-unixware2*
3353 Irix 6.x mips*-sgi-irix6*
3354 PowerPC GNU/Linux powerpc-*-linux*
3355 PowerPC Solaris powerpcle-*-solaris*
3356 Sparc GNU/Linux sparc-*-linux*
3357 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3361 Argonaut Risc Chip (ARC) arc-*-*
3362 Hitachi H8/300S h8300*-*-*
3363 Matsushita MN10200 w/simulator mn10200-*-*
3364 Matsushita MN10300 w/simulator mn10300-*-*
3365 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3366 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3367 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3368 Mitsubishi D10V w/simulator d10v-*-*
3369 Mitsubishi M32R/D w/simulator m32r-*-elf*
3370 Tsqware Sparclet sparclet-*-*
3371 NEC V850 w/simulator v850-*-*
3373 * New debugging protocols
3375 ARM with RDI protocol arm*-*-*
3376 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3377 DDB and LSI variants of PMON protocol mips*-*-*
3378 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3379 PowerPC with SDS protocol powerpc{,le}-*-eabi
3380 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3384 All configurations can now understand and use the DWARF 2 debugging
3385 format. The choice is automatic, if the symbol file contains DWARF 2
3390 GDB now includes basic Java language support. This support is
3391 only useful with Java compilers that produce native machine code.
3393 * solib-absolute-prefix and solib-search-path
3395 For SunOS and SVR4 shared libraries, you may now set the prefix for
3396 loading absolute shared library symbol files, and the search path for
3397 locating non-absolute shared library symbol files.
3399 * Live range splitting
3401 GDB can now effectively debug code for which GCC has performed live
3402 range splitting as part of its optimization. See gdb/doc/LRS for
3403 more details on the expected format of the stabs information.
3407 GDB's support for the GNU Hurd, including thread debugging, has been
3408 updated to work with current versions of the Hurd.
3412 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3413 instruction set. ARM GDB automatically detects when Thumb
3414 instructions are in use, and adjusts disassembly and backtracing
3419 GDB's MIPS target configurations now handle the MIP16 16-bit
3424 GDB now includes support for overlays; if an executable has been
3425 linked such that multiple sections are based at the same address, GDB
3426 will decide which section to use for symbolic info. You can choose to
3427 control the decision manually, using overlay commands, or implement
3428 additional target-side support and use "overlay load-target" to bring
3429 in the overlay mapping. Do "help overlay" for more detail.
3433 The command "info symbol <address>" displays information about
3434 the symbol at the specified address.
3438 The standard remote protocol now includes an extension that allows
3439 asynchronous collection and display of trace data. This requires
3440 extensive support in the target-side debugging stub. Tracing mode
3441 includes a new interaction mode in GDB and new commands: see the
3442 file tracepoint.c for more details.
3446 Configurations for embedded MIPS now include a simulator contributed
3447 by Cygnus Solutions. The simulator supports the instruction sets
3448 of most MIPS variants.
3452 Sparc configurations may now include the ERC32 simulator contributed
3453 by the European Space Agency. The simulator is not built into
3454 Sparc targets by default; configure with --enable-sim to include it.
3458 For target configurations that may include multiple variants of a
3459 basic architecture (such as MIPS and SH), you may now set the
3460 architecture explicitly. "set arch" sets, "info arch" lists
3461 the possible architectures.
3463 *** Changes in GDB-4.16:
3465 * New native configurations
3467 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3468 M68K NetBSD m68k-*-netbsd*
3469 PowerPC AIX 4.x powerpc-*-aix*
3470 PowerPC MacOS powerpc-*-macos*
3471 PowerPC Windows NT powerpcle-*-cygwin32
3472 RS/6000 AIX 4.x rs6000-*-aix4*
3476 ARM with RDP protocol arm-*-*
3477 I960 with MON960 i960-*-coff
3478 MIPS VxWorks mips*-*-vxworks*
3479 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3480 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3482 Matra Sparclet sparclet-*-*
3486 The powerpc-eabi configuration now includes the PSIM simulator,
3487 contributed by Andrew Cagney, with assistance from Mike Meissner.
3488 PSIM is a very elaborate model of the PowerPC, including not only
3489 basic instruction set execution, but also details of execution unit
3490 performance and I/O hardware. See sim/ppc/README for more details.
3494 GDB now works with Solaris 2.5.
3496 * Windows 95/NT native
3498 GDB will now work as a native debugger on Windows 95 and Windows NT.
3499 To build it from source, you must use the "gnu-win32" environment,
3500 which uses a DLL to emulate enough of Unix to run the GNU tools.
3501 Further information, binaries, and sources are available at
3502 ftp.cygnus.com, under pub/gnu-win32.
3504 * dont-repeat command
3506 If a user-defined command includes the command `dont-repeat', then the
3507 command will not be repeated if the user just types return. This is
3508 useful if the command is time-consuming to run, so that accidental
3509 extra keystrokes don't run the same command many times.
3511 * Send break instead of ^C
3513 The standard remote protocol now includes an option to send a break
3514 rather than a ^C to the target in order to interrupt it. By default,
3515 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3517 * Remote protocol timeout
3519 The standard remote protocol includes a new variable `remotetimeout'
3520 that allows you to set the number of seconds before GDB gives up trying
3521 to read from the target. The default value is 2.
3523 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3525 By default GDB will automatically keep track of objects as they are
3526 loaded and unloaded by the dynamic linker. By using the command `set
3527 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3528 when shared library events occur, thus allowing you to set breakpoints
3529 in shared libraries which are explicitly loaded by the inferior.
3531 Note this feature does not work on hpux8. On hpux9 you must link
3532 /usr/lib/end.o into your program. This feature should work
3533 automatically on hpux10.
3535 * Irix 5.x hardware watchpoint support
3537 Irix 5 configurations now support the use of hardware watchpoints.
3539 * Mips protocol "SYN garbage limit"
3541 When debugging a Mips target using the `target mips' protocol, you
3542 may set the number of characters that GDB will ignore by setting
3543 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3544 every character. The default value is 1050.
3546 * Recording and replaying remote debug sessions
3548 If you set `remotelogfile' to the name of a file, gdb will write to it
3549 a recording of a remote debug session. This recording may then be
3550 replayed back to gdb using "gdbreplay". See gdbserver/README for
3551 details. This is useful when you have a problem with GDB while doing
3552 remote debugging; you can make a recording of the session and send it
3553 to someone else, who can then recreate the problem.
3555 * Speedups for remote debugging
3557 GDB includes speedups for downloading and stepping MIPS systems using
3558 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3559 and more efficient S-record downloading.
3561 * Memory use reductions and statistics collection
3563 GDB now uses less memory and reports statistics about memory usage.
3564 Try the `maint print statistics' command, for example.
3566 *** Changes in GDB-4.15:
3568 * Psymtabs for XCOFF
3570 The symbol reader for AIX GDB now uses partial symbol tables. This
3571 can greatly improve startup time, especially for large executables.
3573 * Remote targets use caching
3575 Remote targets now use a data cache to speed up communication with the
3576 remote side. The data cache could lead to incorrect results because
3577 it doesn't know about volatile variables, thus making it impossible to
3578 debug targets which use memory mapped I/O devices. `set remotecache
3579 off' turns the the data cache off.
3581 * Remote targets may have threads
3583 The standard remote protocol now includes support for multiple threads
3584 in the target system, using new protocol commands 'H' and 'T'. See
3585 gdb/remote.c for details.
3589 If GDB is configured with `--enable-netrom', then it will include
3590 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3591 acts as though it is a bank of ROM on the target board, but you can
3592 write into it over the network. GDB's support consists only of
3593 support for fast loading into the emulated ROM; to debug, you must use
3594 another protocol, such as standard remote protocol. The usual
3595 sequence is something like
3597 target nrom <netrom-hostname>
3599 target remote <netrom-hostname>:1235
3603 GDB now includes support for the Apple Macintosh, as a host only. It
3604 may be run as either an MPW tool or as a standalone application, and
3605 it can debug through the serial port. All the usual GDB commands are
3606 available, but to the target command, you must supply "serial" as the
3607 device type instead of "/dev/ttyXX". See mpw-README in the main
3608 directory for more information on how to build. The MPW configuration
3609 scripts */mpw-config.in support only a few targets, and only the
3610 mips-idt-ecoff target has been tested.
3614 GDB configuration now uses autoconf. This is not user-visible,
3615 but does simplify configuration and building.
3619 GDB now supports hpux10.
3621 *** Changes in GDB-4.14:
3623 * New native configurations
3625 x86 FreeBSD i[345]86-*-freebsd
3626 x86 NetBSD i[345]86-*-netbsd
3627 NS32k NetBSD ns32k-*-netbsd
3628 Sparc NetBSD sparc-*-netbsd
3632 A29K VxWorks a29k-*-vxworks
3633 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3634 CPU32 EST-300 emulator m68*-*-est*
3635 PowerPC ELF powerpc-*-elf
3638 * Alpha OSF/1 support for procfs
3640 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3641 possible to attach to running processes. As the mounting of the /proc
3642 filesystem is optional on the Alpha, GDB automatically determines
3643 the availability of /proc during startup. This can lead to problems
3644 if /proc is unmounted after GDB has been started.
3646 * Arguments to user-defined commands
3648 User commands may accept up to 10 arguments separated by whitespace.
3649 Arguments are accessed within the user command via $arg0..$arg9. A
3652 print $arg0 + $arg1 + $arg2
3654 To execute the command use:
3657 Defines the command "adder" which prints the sum of its three arguments.
3658 Note the arguments are text substitutions, so they may reference variables,
3659 use complex expressions, or even perform inferior function calls.
3661 * New `if' and `while' commands
3663 This makes it possible to write more sophisticated user-defined
3664 commands. Both commands take a single argument, which is the
3665 expression to evaluate, and must be followed by the commands to
3666 execute, one per line, if the expression is nonzero, the list being
3667 terminated by the word `end'. The `if' command list may include an
3668 `else' word, which causes the following commands to be executed only
3669 if the expression is zero.
3671 * Fortran source language mode
3673 GDB now includes partial support for Fortran 77. It will recognize
3674 Fortran programs and can evaluate a subset of Fortran expressions, but
3675 variables and functions may not be handled correctly. GDB will work
3676 with G77, but does not yet know much about symbols emitted by other
3679 * Better HPUX support
3681 Most debugging facilities now work on dynamic executables for HPPAs
3682 running hpux9 or later. You can attach to running dynamically linked
3683 processes, but by default the dynamic libraries will be read-only, so
3684 for instance you won't be able to put breakpoints in them. To change
3685 that behavior do the following before running the program:
3691 This will cause the libraries to be mapped private and read-write.
3692 To revert to the normal behavior, do this:
3698 You cannot set breakpoints or examine data in the library until after
3699 the library is loaded if the function/data symbols do not have
3702 GDB can now also read debug symbols produced by the HP C compiler on
3703 HPPAs (sorry, no C++, Fortran or 68k support).
3705 * Target byte order now dynamically selectable
3707 You can choose which byte order to use with a target system, via the
3708 commands "set endian big" and "set endian little", and you can see the
3709 current setting by using "show endian". You can also give the command
3710 "set endian auto", in which case GDB will use the byte order
3711 associated with the executable. Currently, only embedded MIPS
3712 configurations support dynamic selection of target byte order.
3714 * New DOS host serial code
3716 This version uses DPMI interrupts to handle buffered I/O, so you
3717 no longer need to run asynctsr when debugging boards connected to
3720 *** Changes in GDB-4.13:
3722 * New "complete" command
3724 This lists all the possible completions for the rest of the line, if it
3725 were to be given as a command itself. This is intended for use by emacs.
3727 * Trailing space optional in prompt
3729 "set prompt" no longer adds a space for you after the prompt you set. This
3730 allows you to set a prompt which ends in a space or one that does not.
3732 * Breakpoint hit counts
3734 "info break" now displays a count of the number of times the breakpoint
3735 has been hit. This is especially useful in conjunction with "ignore"; you
3736 can ignore a large number of breakpoint hits, look at the breakpoint info
3737 to see how many times the breakpoint was hit, then run again, ignoring one
3738 less than that number, and this will get you quickly to the last hit of
3741 * Ability to stop printing at NULL character
3743 "set print null-stop" will cause GDB to stop printing the characters of
3744 an array when the first NULL is encountered. This is useful when large
3745 arrays actually contain only short strings.
3747 * Shared library breakpoints
3749 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3750 breakpoints in shared libraries before the executable is run.
3752 * Hardware watchpoints
3754 There is a new hardware breakpoint for the watch command for sparclite
3755 targets. See gdb/sparclite/hw_breakpoint.note.
3757 Hardware watchpoints are also now supported under GNU/Linux.
3761 Annotations have been added. These are for use with graphical interfaces,
3762 and are still experimental. Currently only gdba.el uses these.
3764 * Improved Irix 5 support
3766 GDB now works properly with Irix 5.2.
3768 * Improved HPPA support
3770 GDB now works properly with the latest GCC and GAS.
3772 * New native configurations
3774 Sequent PTX4 i[34]86-sequent-ptx4
3775 HPPA running OSF/1 hppa*-*-osf*
3776 Atari TT running SVR4 m68*-*-sysv4*
3777 RS/6000 LynxOS rs6000-*-lynxos*
3781 OS/9000 i[34]86-*-os9k
3782 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3785 * Hitachi SH7000 and E7000-PC ICE support
3787 There is now support for communicating with the Hitachi E7000-PC ICE.
3788 This is available automatically when GDB is configured for the SH.
3792 As usual, a variety of small fixes and improvements, both generic
3793 and configuration-specific. See the ChangeLog for more detail.
3795 *** Changes in GDB-4.12:
3797 * Irix 5 is now supported
3801 GDB-4.12 on the HPPA has a number of changes which make it unable
3802 to debug the output from the currently released versions of GCC and
3803 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3804 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3805 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3808 *** Changes in GDB-4.11:
3810 * User visible changes:
3814 The "set remotedebug" option is now consistent between the mips remote
3815 target, remote targets using the gdb-specific protocol, UDI (AMD's
3816 debug protocol for the 29k) and the 88k bug monitor. It is now an
3817 integer specifying a debug level (normally 0 or 1, but 2 means more
3818 debugging info for the mips target).
3820 * DEC Alpha native support
3822 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3823 debug info, but GDB works fairly well with the DEC compiler and should
3824 work with a future GCC release. See the README file for a few
3825 Alpha-specific notes.
3827 * Preliminary thread implementation
3829 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3831 * LynxOS native and target support for 386
3833 This release has been hosted on LynxOS 2.2, and also can be configured
3834 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3837 * Improvements in C++ mangling/demangling.
3839 This release has much better g++ debugging, specifically in name
3840 mangling/demangling, virtual function calls, print virtual table,
3841 call methods, ...etc.
3843 *** Changes in GDB-4.10:
3845 * User visible changes:
3847 Remote debugging using the GDB-specific (`target remote') protocol now
3848 supports the `load' command. This is only useful if you have some
3849 other way of getting the stub to the target system, and you can put it
3850 somewhere in memory where it won't get clobbered by the download.
3852 Filename completion now works.
3854 When run under emacs mode, the "info line" command now causes the
3855 arrow to point to the line specified. Also, "info line" prints
3856 addresses in symbolic form (as well as hex).
3858 All vxworks based targets now support a user settable option, called
3859 vxworks-timeout. This option represents the number of seconds gdb
3860 should wait for responses to rpc's. You might want to use this if
3861 your vxworks target is, perhaps, a slow software simulator or happens
3862 to be on the far side of a thin network line.
3866 This release contains support for using a DEC alpha as a GDB host for
3867 cross debugging. Native alpha debugging is not supported yet.
3870 *** Changes in GDB-4.9:
3874 This is the first GDB release which is accompanied by a matching testsuite.
3875 The testsuite requires installation of dejagnu, which should be available
3876 via ftp from most sites that carry GNU software.
3880 'Cfront' style demangling has had its name changed to 'ARM' style, to
3881 emphasize that it was written from the specifications in the C++ Annotated
3882 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3883 disclaimers, it still generated too much confusion with users attempting to
3884 use gdb with AT&T cfront.
3888 GDB now uses a standard remote interface to a simulator library.
3889 So far, the library contains simulators for the Zilog Z8001/2, the
3890 Hitachi H8/300, H8/500 and Super-H.
3892 * New targets supported
3894 H8/300 simulator h8300-hitachi-hms or h8300hms
3895 H8/500 simulator h8500-hitachi-hms or h8500hms
3896 SH simulator sh-hitachi-hms or sh
3897 Z8000 simulator z8k-zilog-none or z8ksim
3898 IDT MIPS board over serial line mips-idt-ecoff
3900 Cross-debugging to GO32 targets is supported. It requires a custom
3901 version of the i386-stub.c module which is integrated with the
3902 GO32 memory extender.
3904 * New remote protocols
3906 MIPS remote debugging protocol.
3908 * New source languages supported
3910 This version includes preliminary support for Chill, a Pascal like language
3911 used by telecommunications companies. Chill support is also being integrated
3912 into the GNU compiler, but we don't know when it will be publically available.
3915 *** Changes in GDB-4.8:
3917 * HP Precision Architecture supported
3919 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3920 version of this support was available as a set of patches from the
3921 University of Utah. GDB does not support debugging of programs
3922 compiled with the HP compiler, because HP will not document their file
3923 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3924 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3926 Many problems in the preliminary version have been fixed.
3928 * Faster and better demangling
3930 We have improved template demangling and fixed numerous bugs in the GNU style
3931 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3932 character types (wchar_t) are now supported. Demangling of each symbol is now
3933 only done once, and is cached when the symbol table for a file is read in.
3934 This results in a small increase in memory usage for C programs, a moderate
3935 increase in memory usage for C++ programs, and a fantastic speedup in
3938 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3939 from the specifications in the Annotated Reference Manual, which AT&T's
3940 compiler does not actually implement.
3942 * G++ multiple inheritance compiler problem
3944 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3945 inheritance lattices was reworked to properly discover ambiguities. We
3946 recently found an example which causes this new algorithm to fail in a
3947 very subtle way, producing bad debug information for those classes.
3948 The file 'gcc.patch' (in this directory) can be applied to gcc to
3949 circumvent the problem. A future GCC release will contain a complete
3952 The previous G++ debug info problem (mentioned below for the gdb-4.7
3953 release) is fixed in gcc version 2.3.2.
3955 * Improved configure script
3957 The `configure' script will now attempt to guess your system type if
3958 you don't supply a host system type. The old scheme of supplying a
3959 host system triplet is preferable over using this. All the magic is
3960 done in the new `config.guess' script. Examine it for details.
3962 We have also brought our configure script much more in line with the FSF's
3963 version. It now supports the --with-xxx options. In particular,
3964 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3965 The resulting GDB will not be able to read arbitrary object file formats --
3966 only the format ``expected'' to be used on the configured target system.
3967 We hope to make this the default in a future release.
3969 * Documentation improvements
3971 There's new internal documentation on how to modify GDB, and how to
3972 produce clean changes to the code. We implore people to read it
3973 before submitting changes.
3975 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3976 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3977 `info' files are also provided. To build `info' files from scratch,
3978 you will need the latest `makeinfo' release, which will be available in
3979 a future texinfo-X.Y release.
3981 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3982 We're not sure exactly which versions have this problem, but it has
3983 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3984 or better. If that isn't possible, there is a patch in
3985 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3986 around this problem.
3990 GDB now supports array constants that can be used in expressions typed in by
3991 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3992 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3995 The new directory `gdb/sparclite' contains a program that demonstrates
3996 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3998 * New native hosts supported
4000 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4001 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4003 * New targets supported
4005 AMD 29k family via UDI a29k-amd-udi or udi29k
4007 * New file formats supported
4009 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4010 HPUX core files, and SCO 3.2v2 core files.
4014 Attaching to processes now works again; thanks for the many bug reports.
4016 We have also stomped on a bunch of core dumps caused by
4017 printf_filtered("%s") problems.
4019 We eliminated a copyright problem on the rpc and ptrace header files
4020 for VxWorks, which was discovered at the last minute during the 4.7
4021 release. You should now be able to build a VxWorks GDB.
4023 You can now interrupt gdb while an attached process is running. This
4024 will cause the attached process to stop, and give control back to GDB.
4026 We fixed problems caused by using too many file descriptors
4027 for reading symbols from object files and libraries. This was
4028 especially a problem for programs that used many (~100) shared
4031 The `step' command now only enters a subroutine if there is line number
4032 information for the subroutine. Otherwise it acts like the `next'
4033 command. Previously, `step' would enter subroutines if there was
4034 any debugging information about the routine. This avoids problems
4035 when using `cc -g1' on MIPS machines.
4037 * Internal improvements
4039 GDB's internal interfaces have been improved to make it easier to support
4040 debugging of multiple languages in the future.
4042 GDB now uses a common structure for symbol information internally.
4043 Minimal symbols (derived from linkage symbols in object files), partial
4044 symbols (from a quick scan of debug information), and full symbols
4045 contain a common subset of information, making it easier to write
4046 shared code that handles any of them.
4048 * New command line options
4050 We now accept --silent as an alias for --quiet.
4054 The memory-mapped-malloc library is now licensed under the GNU Library
4055 General Public License.
4057 *** Changes in GDB-4.7:
4059 * Host/native/target split
4061 GDB has had some major internal surgery to untangle the support for
4062 hosts and remote targets. Now, when you configure GDB for a remote
4063 target, it will no longer load in all of the support for debugging
4064 local programs on the host. When fully completed and tested, this will
4065 ensure that arbitrary host/target combinations are possible.
4067 The primary conceptual shift is to separate the non-portable code in
4068 GDB into three categories. Host specific code is required any time GDB
4069 is compiled on that host, regardless of the target. Target specific
4070 code relates to the peculiarities of the target, but can be compiled on
4071 any host. Native specific code is everything else: it can only be
4072 built when the host and target are the same system. Child process
4073 handling and core file support are two common `native' examples.
4075 GDB's use of /proc for controlling Unix child processes is now cleaner.
4076 It has been split out into a single module under the `target_ops' vector,
4077 plus two native-dependent functions for each system that uses /proc.
4079 * New hosts supported
4081 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4082 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4083 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4085 * New targets supported
4087 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4088 68030 and CPU32 m68030-*-*, m68332-*-*
4090 * New native hosts supported
4092 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4093 (386bsd is not well tested yet)
4094 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4096 * New file formats supported
4098 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4099 supports reading of `a.out.adobe' object files, which are an a.out
4100 format extended with minimal information about multiple sections.
4104 `show copying' is the same as the old `info copying'.
4105 `show warranty' is the same as `info warrantee'.
4106 These were renamed for consistency. The old commands continue to work.
4108 `info handle' is a new alias for `info signals'.
4110 You can now define pre-command hooks, which attach arbitrary command
4111 scripts to any command. The commands in the hook will be executed
4112 prior to the user's command. You can also create a hook which will be
4113 executed whenever the program stops. See gdb.texinfo.
4117 We now deal with Cfront style name mangling, and can even extract type
4118 info from mangled symbols. GDB can automatically figure out which
4119 symbol mangling style your C++ compiler uses.
4121 Calling of methods and virtual functions has been improved as well.
4125 The crash that occured when debugging Sun Ansi-C compiled binaries is
4126 fixed. This was due to mishandling of the extra N_SO stabs output
4129 We also finally got Ultrix 4.2 running in house, and fixed core file
4130 support, with help from a dozen people on the net.
4132 John M. Farrell discovered that the reason that single-stepping was so
4133 slow on all of the Mips based platforms (primarily SGI and DEC) was
4134 that we were trying to demangle and lookup a symbol used for internal
4135 purposes on every instruction that was being stepped through. Changing
4136 the name of that symbol so that it couldn't be mistaken for a C++
4137 mangled symbol sped things up a great deal.
4139 Rich Pixley sped up symbol lookups in general by getting much smarter
4140 about when C++ symbol mangling is necessary. This should make symbol
4141 completion (TAB on the command line) much faster. It's not as fast as
4142 we'd like, but it's significantly faster than gdb-4.6.
4146 A new user controllable variable 'call_scratch_address' can
4147 specify the location of a scratch area to be used when GDB
4148 calls a function in the target. This is necessary because the
4149 usual method of putting the scratch area on the stack does not work
4150 in systems that have separate instruction and data spaces.
4152 We integrated changes to support the 29k UDI (Universal Debugger
4153 Interface), but discovered at the last minute that we didn't have all
4154 of the appropriate copyright paperwork. We are working with AMD to
4155 resolve this, and hope to have it available soon.
4159 We have sped up the remote serial line protocol, especially for targets
4160 with lots of registers. It now supports a new `expedited status' ('T')
4161 message which can be used in place of the existing 'S' status message.
4162 This allows the remote stub to send only the registers that GDB
4163 needs to make a quick decision about single-stepping or conditional
4164 breakpoints, eliminating the need to fetch the entire register set for
4165 each instruction being stepped through.
4167 The GDB remote serial protocol now implements a write-through cache for
4168 registers, only re-reading the registers if the target has run.
4170 There is also a new remote serial stub for SPARC processors. You can
4171 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4172 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4173 processor with a serial port.
4177 Configure.in files have become much easier to read and modify. A new
4178 `table driven' format makes it more obvious what configurations are
4179 supported, and what files each one uses.
4183 There is a new opcodes library which will eventually contain all of the
4184 disassembly routines and opcode tables. At present, it only contains
4185 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4186 disassembler (binutils/objdump) to share these routines.
4188 The libiberty library is now copylefted under the GNU Library General
4189 Public License. This allows more liberal use, and was done so libg++
4190 can use it. This makes no difference to GDB, since the Library License
4191 grants all the rights from the General Public License.
4195 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4196 reference to the stabs symbol info used by the debugger. It is (as far
4197 as we know) the only published document on this fascinating topic. We
4198 encourage you to read it, compare it to the stabs information on your
4199 system, and send improvements on the document in general (to
4200 bug-gdb@prep.ai.mit.edu).
4202 And, of course, many bugs have been fixed.
4205 *** Changes in GDB-4.6:
4207 * Better support for C++ function names
4209 GDB now accepts as input the "demangled form" of C++ overloaded function
4210 names and member function names, and can do command completion on such names
4211 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4212 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4213 Make use of command completion, it is your friend.
4215 GDB also now accepts a variety of C++ mangled symbol formats. They are
4216 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4217 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4218 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4219 for the list of formats.
4221 * G++ symbol mangling problem
4223 Recent versions of gcc have a bug in how they emit debugging information for
4224 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4225 directory) can be applied to gcc to fix the problem. Alternatively, if you
4226 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4227 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4228 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4231 * New 'maintenance' command
4233 All of the commands related to hacking GDB internals have been moved out of
4234 the main command set, and now live behind the 'maintenance' command. This
4235 can also be abbreviated as 'mt'. The following changes were made:
4237 dump-me -> maintenance dump-me
4238 info all-breakpoints -> maintenance info breakpoints
4239 printmsyms -> maintenance print msyms
4240 printobjfiles -> maintenance print objfiles
4241 printpsyms -> maintenance print psymbols
4242 printsyms -> maintenance print symbols
4244 The following commands are new:
4246 maintenance demangle Call internal GDB demangler routine to
4247 demangle a C++ link name and prints the result.
4248 maintenance print type Print a type chain for a given symbol
4250 * Change to .gdbinit file processing
4252 We now read the $HOME/.gdbinit file before processing the argv arguments
4253 (e.g. reading symbol files or core files). This allows global parameters to
4254 be set, which will apply during the symbol reading. The ./.gdbinit is still
4255 read after argv processing.
4257 * New hosts supported
4259 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4261 GNU/Linux support i386-unknown-linux or linux
4263 We are also including code to support the HP/PA running BSD and HPUX. This
4264 is almost guaranteed not to work, as we didn't have time to test or build it
4265 for this release. We are including it so that the more adventurous (or
4266 masochistic) of you can play with it. We also had major problems with the
4267 fact that the compiler that we got from HP doesn't support the -g option.
4270 * New targets supported
4272 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4274 * More smarts about finding #include files
4276 GDB now remembers the compilation directory for all include files, and for
4277 all files from which C is generated (like yacc and lex sources). This
4278 greatly improves GDB's ability to find yacc/lex sources, and include files,
4279 especially if you are debugging your program from a directory different from
4280 the one that contains your sources.
4282 We also fixed a bug which caused difficulty with listing and setting
4283 breakpoints in include files which contain C code. (In the past, you had to
4284 try twice in order to list an include file that you hadn't looked at before.)
4286 * Interesting infernals change
4288 GDB now deals with arbitrary numbers of sections, where the symbols for each
4289 section must be relocated relative to that section's landing place in the
4290 target's address space. This work was needed to support ELF with embedded
4291 stabs used by Solaris-2.0.
4293 * Bug fixes (of course!)
4295 There have been loads of fixes for the following things:
4296 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4297 i960, stabs, DOS(GO32), procfs, etc...
4299 See the ChangeLog for details.
4301 *** Changes in GDB-4.5:
4303 * New machines supported (host and target)
4305 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4307 SGI Irix-4.x mips-sgi-irix4 or iris4
4309 * New malloc package
4311 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4312 Mmalloc is capable of handling mutiple heaps of memory. It is also
4313 capable of saving a heap to a file, and then mapping it back in later.
4314 This can be used to greatly speedup the startup of GDB by using a
4315 pre-parsed symbol table which lives in a mmalloc managed heap. For
4316 more details, please read mmalloc/mmalloc.texi.
4320 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4321 'help info proc' for details.
4323 * MIPS ecoff symbol table format
4325 The code that reads MIPS symbol table format is now supported on all hosts.
4326 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4329 * File name changes for MS-DOS
4331 Many files in the config directories have been renamed to make it easier to
4332 support GDB on MS-DOSe systems (which have very restrictive file name
4333 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4334 environment) is close to working but has some remaining problems. Note
4335 that debugging of DOS programs is not supported, due to limitations
4336 in the ``operating system'', but it can be used to host cross-debugging.
4338 * Cross byte order fixes
4340 Many fixes have been made to support cross debugging of Sparc and MIPS
4341 targets from hosts whose byte order differs.
4343 * New -mapped and -readnow options
4345 If memory-mapped files are available on your system through the 'mmap'
4346 system call, you can use the -mapped option on the `file' or
4347 `symbol-file' commands to cause GDB to write the symbols from your
4348 program into a reusable file. If the program you are debugging is
4349 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4350 Future GDB debugging sessions will notice the presence of this file,
4351 and will quickly map in symbol information from it, rather than reading
4352 the symbol table from the executable program. Using the '-mapped'
4353 option in a GDB `file' or `symbol-file' command has the same effect as
4354 starting GDB with the '-mapped' command-line option.
4356 You can cause GDB to read the entire symbol table immediately by using
4357 the '-readnow' option with any of the commands that load symbol table
4358 information (or on the GDB command line). This makes the command
4359 slower, but makes future operations faster.
4361 The -mapped and -readnow options are typically combined in order to
4362 build a `fred.syms' file that contains complete symbol information.
4363 A simple GDB invocation to do nothing but build a `.syms' file for future
4366 gdb -batch -nx -mapped -readnow programname
4368 The `.syms' file is specific to the host machine on which GDB is run.
4369 It holds an exact image of GDB's internal symbol table. It cannot be
4370 shared across multiple host platforms.
4372 * longjmp() handling
4374 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4375 siglongjmp() without losing control. This feature has not yet been ported to
4376 all systems. It currently works on many 386 platforms, all MIPS-based
4377 platforms (SGI, DECstation, etc), and Sun3/4.
4381 Preliminary work has been put in to support the new Solaris OS from Sun. At
4382 this time, it can control and debug processes, but it is not capable of
4387 As always, many many bug fixes. The major areas were with g++, and mipsread.
4388 People using the MIPS-based platforms should experience fewer mysterious
4389 crashes and trashed symbol tables.
4391 *** Changes in GDB-4.4:
4393 * New machines supported (host and target)
4395 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4397 BSD Reno on Vax vax-dec-bsd
4398 Ultrix on Vax vax-dec-ultrix
4400 * New machines supported (target)
4402 AMD 29000 embedded, using EBMON a29k-none-none
4406 GDB continues to improve its handling of C++. `References' work better.
4407 The demangler has also been improved, and now deals with symbols mangled as
4408 per the Annotated C++ Reference Guide.
4410 GDB also now handles `stabs' symbol information embedded in MIPS
4411 `ecoff' symbol tables. Since the ecoff format was not easily
4412 extensible to handle new languages such as C++, this appeared to be a
4413 good way to put C++ debugging info into MIPS binaries. This option
4414 will be supported in the GNU C compiler, version 2, when it is
4417 * New features for SVR4
4419 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4420 shared libraries. Debugging dynamically linked programs should present
4421 only minor differences from debugging statically linked programs.
4423 The `info proc' command will print out information about any process
4424 on an SVR4 system (including the one you are debugging). At the moment,
4425 it prints the address mappings of the process.
4427 If you bring up GDB on another SVR4 system, please send mail to
4428 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4430 * Better dynamic linking support in SunOS
4432 Reading symbols from shared libraries which contain debugging symbols
4433 now works properly. However, there remain issues such as automatic
4434 skipping of `transfer vector' code during function calls, which
4435 make it harder to debug code in a shared library, than to debug the
4436 same code linked statically.
4440 GDB is now using the latest `getopt' routines from the FSF. This
4441 version accepts the -- prefix for options with long names. GDB will
4442 continue to accept the old forms (-option and +option) as well.
4443 Various single letter abbreviations for options have been explicity
4444 added to the option table so that they won't get overshadowed in the
4445 future by other options that begin with the same letter.
4449 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4450 Many assorted bugs have been handled. Many more remain to be handled.
4451 See the various ChangeLog files (primarily in gdb and bfd) for details.
4454 *** Changes in GDB-4.3:
4456 * New machines supported (host and target)
4458 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4459 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4460 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4462 * Almost SCO Unix support
4464 We had hoped to support:
4465 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4466 (except for core file support), but we discovered very late in the release
4467 that it has problems with process groups that render gdb unusable. Sorry
4468 about that. I encourage people to fix it and post the fixes.
4470 * Preliminary ELF and DWARF support
4472 GDB can read ELF object files on System V Release 4, and can handle
4473 debugging records for C, in DWARF format, in ELF files. This support
4474 is preliminary. If you bring up GDB on another SVR4 system, please
4475 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4480 GDB now uses the latest `readline' library. One user-visible change
4481 is that two tabs will list possible command completions, which previously
4482 required typing M-? (meta-question mark, or ESC ?).
4486 The `stepi' bug that many of you noticed has been squashed.
4487 Many bugs in C++ have been handled. Many more remain to be handled.
4488 See the various ChangeLog files (primarily in gdb and bfd) for details.
4490 * State of the MIPS world (in case you wondered):
4492 GDB can understand the symbol tables emitted by the compilers
4493 supplied by most vendors of MIPS-based machines, including DEC. These
4494 symbol tables are in a format that essentially nobody else uses.
4496 Some versions of gcc come with an assembler post-processor called
4497 mips-tfile. This program is required if you want to do source-level
4498 debugging of gcc-compiled programs. I believe FSF does not ship
4499 mips-tfile with gcc version 1, but it will eventually come with gcc
4502 Debugging of g++ output remains a problem. g++ version 1.xx does not
4503 really support it at all. (If you're lucky, you should be able to get
4504 line numbers and stack traces to work, but no parameters or local
4505 variables.) With some work it should be possible to improve the
4508 When gcc version 2 is released, you will have somewhat better luck.
4509 However, even then you will get confusing results for inheritance and
4512 We will eventually provide full debugging of g++ output on
4513 DECstations. This will probably involve some kind of stabs-in-ecoff
4514 encapulation, but the details have not been worked out yet.
4517 *** Changes in GDB-4.2:
4519 * Improved configuration
4521 Only one copy of `configure' exists now, and it is not self-modifying.
4522 Porting BFD is simpler.
4526 The `step' and `next' commands now only stop at the first instruction
4527 of a source line. This prevents the multiple stops that used to occur
4528 in switch statements, for-loops, etc. `Step' continues to stop if a
4529 function that has debugging information is called within the line.
4533 Lots of small bugs fixed. More remain.
4535 * New host supported (not target)
4537 Intel 386 PC clone running Mach i386-none-mach
4540 *** Changes in GDB-4.1:
4542 * Multiple source language support
4544 GDB now has internal scaffolding to handle several source languages.
4545 It determines the type of each source file from its filename extension,
4546 and will switch expression parsing and number formatting to match the
4547 language of the function in the currently selected stack frame.
4548 You can also specifically set the language to be used, with
4549 `set language c' or `set language modula-2'.
4553 GDB now has preliminary support for the GNU Modula-2 compiler,
4554 currently under development at the State University of New York at
4555 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4556 continue through the fall of 1991 and into 1992.
4558 Other Modula-2 compilers are currently not supported, and attempting to
4559 debug programs compiled with them will likely result in an error as the
4560 symbol table is read. Feel free to work on it, though!
4562 There are hooks in GDB for strict type checking and range checking,
4563 in the `Modula-2 philosophy', but they do not currently work.
4567 GDB can now write to executable and core files (e.g. patch
4568 a variable's value). You must turn this switch on, specify
4569 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4570 by assigning a new value to a variable. Modifications take
4573 * Automatic SunOS shared library reading
4575 When you run your program, GDB automatically determines where its
4576 shared libraries (if any) have been loaded, and reads their symbols.
4577 The `share' command is no longer needed. This also works when
4578 examining core files.
4582 You can specify the number of lines that the `list' command shows.
4585 * New machines supported (host and target)
4587 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4588 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4589 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4591 * New hosts supported (not targets)
4593 IBM RT/PC: romp-ibm-aix or rtpc
4595 * New targets supported (not hosts)
4597 AMD 29000 embedded with COFF a29k-none-coff
4598 AMD 29000 embedded with a.out a29k-none-aout
4599 Ultracomputer remote kernel debug a29k-nyu-kern
4601 * New remote interfaces
4607 *** Changes in GDB-4.0:
4611 Wide output is wrapped at good places to make the output more readable.
4613 Gdb now supports cross-debugging from a host machine of one type to a
4614 target machine of another type. Communication with the target system
4615 is over serial lines. The ``target'' command handles connecting to the
4616 remote system; the ``load'' command will download a program into the
4617 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4618 also supports debugging of realtime processes running under VxWorks,
4619 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4620 stub on the target system.
4622 New CPUs supported include the AMD 29000 and Intel 960.
4624 GDB now reads object files and symbol tables via a ``binary file''
4625 library, which allows a single copy of GDB to debug programs of multiple
4626 object file types such as a.out and coff.
4628 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4629 refcard.dvi and refcard.ps are available to format it).
4632 * Control-Variable user interface simplified
4634 All variables that control the operation of the debugger can be set
4635 by the ``set'' command, and displayed by the ``show'' command.
4637 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4638 ``Show prompt'' produces the response:
4639 Gdb's prompt is new-gdb=>.
4641 What follows are the NEW set commands. The command ``help set'' will
4642 print a complete list of old and new set commands. ``help set FOO''
4643 will give a longer description of the variable FOO. ``show'' will show
4644 all of the variable descriptions and their current settings.
4646 confirm on/off: Enables warning questions for operations that are
4647 hard to recover from, e.g. rerunning the program while
4648 it is already running. Default is ON.
4650 editing on/off: Enables EMACS style command line editing
4651 of input. Previous lines can be recalled with
4652 control-P, the current line can be edited with control-B,
4653 you can search for commands with control-R, etc.
4656 history filename NAME: NAME is where the gdb command history
4657 will be stored. The default is .gdb_history,
4658 or the value of the environment variable
4661 history size N: The size, in commands, of the command history. The
4662 default is 256, or the value of the environment variable
4665 history save on/off: If this value is set to ON, the history file will
4666 be saved after exiting gdb. If set to OFF, the
4667 file will not be saved. The default is OFF.
4669 history expansion on/off: If this value is set to ON, then csh-like
4670 history expansion will be performed on
4671 command line input. The default is OFF.
4673 radix N: Sets the default radix for input and output. It can be set
4674 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4675 in the current radix, so "set radix 10" is always a no-op.
4677 height N: This integer value is the number of lines on a page. Default
4678 is 24, the current `stty rows'' setting, or the ``li#''
4679 setting from the termcap entry matching the environment
4682 width N: This integer value is the number of characters on a line.
4683 Default is 80, the current `stty cols'' setting, or the ``co#''
4684 setting from the termcap entry matching the environment
4687 Note: ``set screensize'' is obsolete. Use ``set height'' and
4688 ``set width'' instead.
4690 print address on/off: Print memory addresses in various command displays,
4691 such as stack traces and structure values. Gdb looks
4692 more ``symbolic'' if you turn this off; it looks more
4693 ``machine level'' with it on. Default is ON.
4695 print array on/off: Prettyprint arrays. New convenient format! Default
4698 print demangle on/off: Print C++ symbols in "source" form if on,
4701 print asm-demangle on/off: Same, for assembler level printouts
4704 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4707 * Support for Epoch Environment.
4709 The epoch environment is a version of Emacs v18 with windowing. One
4710 new command, ``inspect'', is identical to ``print'', except that if you
4711 are running in the epoch environment, the value is printed in its own
4715 * Support for Shared Libraries
4717 GDB can now debug programs and core files that use SunOS shared libraries.
4718 Symbols from a shared library cannot be referenced
4719 before the shared library has been linked with the program (this
4720 happens after you type ``run'' and before the function main() is entered).
4721 At any time after this linking (including when examining core files
4722 from dynamically linked programs), gdb reads the symbols from each
4723 shared library when you type the ``sharedlibrary'' command.
4724 It can be abbreviated ``share''.
4726 sharedlibrary REGEXP: Load shared object library symbols for files
4727 matching a unix regular expression. No argument
4728 indicates to load symbols for all shared libraries.
4730 info sharedlibrary: Status of loaded shared libraries.
4735 A watchpoint stops execution of a program whenever the value of an
4736 expression changes. Checking for this slows down execution
4737 tremendously whenever you are in the scope of the expression, but is
4738 quite useful for catching tough ``bit-spreader'' or pointer misuse
4739 problems. Some machines such as the 386 have hardware for doing this
4740 more quickly, and future versions of gdb will use this hardware.
4742 watch EXP: Set a watchpoint (breakpoint) for an expression.
4744 info watchpoints: Information about your watchpoints.
4746 delete N: Deletes watchpoint number N (same as breakpoints).
4747 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4748 enable N: Re-enables watchpoint number N (same as breakpoints).
4751 * C++ multiple inheritance
4753 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4756 * C++ exception handling
4758 Gdb now supports limited C++ exception handling. Besides the existing
4759 ability to breakpoint on an exception handler, gdb can breakpoint on
4760 the raising of an exception (before the stack is peeled back to the
4763 catch FOO: If there is a FOO exception handler in the dynamic scope,
4764 set a breakpoint to catch exceptions which may be raised there.
4765 Multiple exceptions (``catch foo bar baz'') may be caught.
4767 info catch: Lists all exceptions which may be caught in the
4768 current stack frame.
4771 * Minor command changes
4773 The command ``call func (arg, arg, ...)'' now acts like the print
4774 command, except it does not print or save a value if the function's result
4775 is void. This is similar to dbx usage.
4777 The ``up'' and ``down'' commands now always print the frame they end up
4778 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4779 frames without printing.
4781 * New directory command
4783 'dir' now adds directories to the FRONT of the source search path.
4784 The path starts off empty. Source files that contain debug information
4785 about the directory in which they were compiled can be found even
4786 with an empty path; Sun CC and GCC include this information. If GDB can't
4787 find your source file in the current directory, type "dir .".
4789 * Configuring GDB for compilation
4791 For normal use, type ``./configure host''. See README or gdb.texinfo
4794 GDB now handles cross debugging. If you are remotely debugging between
4795 two different machines, type ``./configure host -target=targ''.
4796 Host is the machine where GDB will run; targ is the machine
4797 where the program that you are debugging will run.