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 * GDBserver now supports stdio connections.
11 E.g. (gdb) target remote | ssh myhost gdbserver - hello
13 * The binary "gdbtui" can no longer be built or installed.
14 Use "gdb -tui" instead.
16 * GDB will now print "flag" enums specially. A flag enum is one where
17 all the enumerator values have no bits in common when pairwise
18 "and"ed. When printing a value whose type is a flag enum, GDB will
19 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
20 (gdb) print (enum E) 3
25 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
26 apply "flag enum"-style pretty-printing to any enum.
28 *** Changes in GDB 7.4
30 * GDB now handles ambiguous linespecs more consistently; the existing
31 FILE:LINE support has been expanded to other types of linespecs. A
32 breakpoint will now be set on all matching locations in all
33 inferiors, and locations will be added or removed according to
36 * GDB now allows you to skip uninteresting functions and files when
37 stepping with the "skip function" and "skip file" commands.
39 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
40 and "show remote hardware-watchpoint-length-limit". These allows to
41 set or show the maximum length limit (in bytes) of a remote
42 target hardware watchpoint.
44 This allows e.g. to use "unlimited" hardware watchpoints with the
45 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
46 watchpoints are slower than real hardware watchpoints but are
47 significantly faster than gdb software watchpoints.
51 ** The register_pretty_printer function in module gdb.printing now takes
52 an optional `replace' argument. If True, the new printer replaces any
55 ** The "maint set python print-stack on|off" command has been
56 deprecated and will be deleted in GDB 7.5.
57 A new command: "set python print-stack none|full|message" has
58 replaced it. Additionally, the default for "print-stack" is
59 now "message", which just prints the error message without
62 ** A prompt substitution hook (prompt_hook) is now available to the
65 ** A new Python module, gdb.prompt has been added to the GDB Python
66 modules library. This module provides functionality for
67 escape sequences in prompts (used by set/show
68 extended-prompt). These escape sequences are replaced by their
71 ** Python commands and convenience-functions located in
72 'data-directory'/python/gdb/command and
73 'data-directory'/python/gdb/function are now automatically loaded
76 ** Blocks now provide four new attributes. global_block and
77 static_block will return the global and static blocks
78 respectively. is_static and is_global are boolean attributes
79 that indicate if the block is one of those two types.
81 ** Symbols now provide the "type" attribute, the type of the symbol.
83 ** The "gdb.breakpoint" function has been deprecated in favor of
86 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
87 of a function. This class is based on the "finish" command
90 ** Type objects for struct and union types now allow access to
91 the fields using standard Python dictionary (mapping) methods.
92 For example, "some_type['myfield']" now works, as does
95 ** A new event "gdb.new_objfile" has been added, triggered by loading a
98 ** A new function, "deep_items" has been added to the gdb.types
99 module in the GDB Python modules library. This function returns
100 an iterator over the fields of a struct or union type. Unlike
101 the standard Python "iteritems" method, it will recursively traverse
102 any anonymous fields.
106 ** "*stopped" events can report several new "reason"s, such as
109 ** Breakpoint changes are now notified using new async records, like
110 "=breakpoint-modified".
112 ** New command -ada-task-info.
114 * libthread-db-search-path now supports two special values: $sdir and $pdir.
115 $sdir specifies the default system locations of shared libraries.
116 $pdir specifies the directory where the libpthread used by the application
119 GDB no longer looks in $sdir and $pdir after it has searched the directories
120 mentioned in libthread-db-search-path. If you want to search those
121 directories, they must be specified in libthread-db-search-path.
122 The default value of libthread-db-search-path on GNU/Linux and Solaris
123 systems is now "$sdir:$pdir".
125 $pdir is not supported by gdbserver, it is currently ignored.
126 $sdir is supported by gdbserver.
128 * New configure option --with-iconv-bin.
129 When using the internationalization support like the one in the GNU C
130 library, GDB will invoke the "iconv" program to get a list of supported
131 character sets. If this program lives in a non-standard location, one can
132 use this option to specify where to find it.
134 * When natively debugging programs on PowerPC BookE processors running
135 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
136 watchpoints, which specify a mask in addition to an address to watch.
137 The mask specifies that some bits of an address (the bits which are
138 reset in the mask) should be ignored when matching the address accessed
139 by the inferior against the watchpoint address. See the "PowerPC Embedded"
140 section in the user manual for more details.
142 * The new option --once causes GDBserver to stop listening for connections once
143 the first connection is made. The listening port used by GDBserver will
144 become available after that.
146 * New commands "info macros" and "alias" have been added.
148 * New function parameters suffix @entry specifies value of function parameter
149 at the time the function got called. Entry values are available only since
155 "!" is now an alias of the "shell" command.
156 Note that no space is needed between "!" and SHELL COMMAND.
160 watch EXPRESSION mask MASK_VALUE
161 The watch command now supports the mask argument which allows creation
162 of masked watchpoints, if the current architecture supports this feature.
164 info auto-load-scripts [REGEXP]
165 This command was formerly named "maintenance print section-scripts".
166 It is now generally useful and is no longer a maintenance-only command.
168 info macro [-all] [--] MACRO
169 The info macro command has new options `-all' and `--'. The first for
170 printing all definitions of a macro. The second for explicitly specifying
171 the end of arguments and the beginning of the macro name in case the macro
172 name starts with a hyphen.
174 collect[/s] EXPRESSIONS
175 The tracepoint collect command now takes an optional modifier "/s"
176 that directs it to dereference pointer-to-character types and
177 collect the bytes of memory up to a zero byte. The behavior is
178 similar to what you see when you use the regular print command on a
179 string. An optional integer following the "/s" sets a bound on the
180 number of bytes that will be collected.
183 The trace start command now interprets any supplied arguments as a
184 note to be recorded with the trace run, with an effect similar to
185 setting the variable trace-notes.
188 The trace stop command now interprets any arguments as a note to be
189 mentioned along with the tstatus report that the trace was stopped
190 with a command. The effect is similar to setting the variable
193 * Tracepoints can now be enabled and disabled at any time after a trace
194 experiment has been started using the standard "enable" and "disable"
195 commands. It is now possible to start a trace experiment with no enabled
196 tracepoints; GDB will display a warning, but will allow the experiment to
197 begin, assuming that tracepoints will be enabled as needed while the trace
200 * Fast tracepoints on 32-bit x86-architectures can now be placed at
201 locations with 4-byte instructions, when they were previously
202 limited to locations with instructions of 5 bytes or longer.
208 Set the GDB prompt, and allow escape sequences to be inserted to
209 display miscellaneous information (see 'help set extended-prompt'
210 for the list of sequences). This prompt (and any information
211 accessed through the escape sequences) is updated every time the
214 set print entry-values (both|compact|default|if-needed|no|only|preferred)
215 show print entry-values
216 Set printing of frame argument values at function entry. In some cases
217 GDB can determine the value of function argument which was passed by the
218 function caller, even if the value was modified inside the called function.
220 set debug entry-values
221 show debug entry-values
222 Control display of debugging info for determining frame argument values at
223 function entry and virtual tail call frames.
225 set basenames-may-differ
226 show basenames-may-differ
227 Set whether a source file may have multiple base names.
228 (A "base name" is the name of a file with the directory part removed.
229 Example: The base name of "/home/user/hello.c" is "hello.c".)
230 If set, GDB will canonicalize file names (e.g., expand symlinks)
231 before comparing them. Canonicalization is an expensive operation,
232 but it allows the same file be known by more than one base name.
233 If not set (the default), all source files are assumed to have just
234 one base name, and gdb will do file name comparisons more efficiently.
240 Set a user name and notes for the current and any future trace runs.
241 This is useful for long-running and/or disconnected traces, to
242 inform others (or yourself) as to who is running the trace, supply
243 contact information, or otherwise explain what is going on.
246 show trace-stop-notes
247 Set a note attached to the trace run, that is displayed when the
248 trace has been stopped by a tstop command. This is useful for
249 instance as an explanation, if you are stopping a trace run that was
250 started by someone else.
256 Dynamically enable a tracepoint in a started trace experiment.
260 Dynamically disable a tracepoint in a started trace experiment.
264 Set the user and notes of the trace run.
268 Query the current status of a tracepoint.
272 Query the minimum length of instruction at which a fast tracepoint may
275 * Dcache size (number of lines) and line-size are now runtime-configurable
276 via "set dcache line" and "set dcache line-size" commands.
280 Texas Instruments TMS320C6x tic6x-*-*
284 Renesas RL78 rl78-*-elf
286 *** Changes in GDB 7.3.1
288 * The build failure for NetBSD and OpenBSD targets have now been fixed.
290 *** Changes in GDB 7.3
292 * GDB has a new command: "thread find [REGEXP]".
293 It finds the thread id whose name, target id, or thread extra info
294 matches the given regular expression.
296 * The "catch syscall" command now works on mips*-linux* targets.
298 * The -data-disassemble MI command now supports modes 2 and 3 for
299 dumping the instruction opcodes.
301 * New command line options
303 -data-directory DIR Specify DIR as the "data-directory".
304 This is mostly for testing purposes.
306 * The "maint set python auto-load on|off" command has been renamed to
307 "set auto-load-scripts on|off".
309 * GDB has a new command: "set directories".
310 It is like the "dir" command except that it replaces the
311 source path list instead of augmenting it.
313 * GDB now understands thread names.
315 On GNU/Linux, "info threads" will display the thread name as set by
316 prctl or pthread_setname_np.
318 There is also a new command, "thread name", which can be used to
319 assign a name internally for GDB to display.
322 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
323 has been integrated into GDB.
327 ** The function gdb.Write now accepts an optional keyword 'stream'.
328 This keyword, when provided, will direct the output to either
329 stdout, stderr, or GDB's logging output.
331 ** Parameters can now be be sub-classed in Python, and in particular
332 you may implement the get_set_doc and get_show_doc functions.
333 This improves how Parameter set/show documentation is processed
334 and allows for more dynamic content.
336 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
337 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
338 have an is_valid method.
340 ** Breakpoints can now be sub-classed in Python, and in particular
341 you may implement a 'stop' function that is executed each time
342 the inferior reaches that breakpoint.
344 ** New function gdb.lookup_global_symbol looks up a global symbol.
346 ** GDB values in Python are now callable if the value represents a
347 function. For example, if 'some_value' represents a function that
348 takes two integer parameters and returns a value, you can call
349 that function like so:
351 result = some_value (10,20)
353 ** Module gdb.types has been added.
354 It contains a collection of utilities for working with gdb.Types objects:
355 get_basic_type, has_field, make_enum_dict.
357 ** Module gdb.printing has been added.
358 It contains utilities for writing and registering pretty-printers.
359 New classes: PrettyPrinter, SubPrettyPrinter,
360 RegexpCollectionPrettyPrinter.
361 New function: register_pretty_printer.
363 ** New commands "info pretty-printers", "enable pretty-printer" and
364 "disable pretty-printer" have been added.
366 ** gdb.parameter("directories") is now available.
368 ** New function gdb.newest_frame returns the newest frame in the
371 ** The gdb.InferiorThread class has a new "name" attribute. This
372 holds the thread's name.
374 ** Python Support for Inferior events.
375 Python scripts can add observers to be notified of events
376 occurring in the process being debugged.
377 The following events are currently supported:
378 - gdb.events.cont Continue event.
379 - gdb.events.exited Inferior exited event.
380 - gdb.events.stop Signal received, and Breakpoint hit events.
384 ** GDB now puts template parameters in scope when debugging in an
385 instantiation. For example, if you have:
387 template<int X> int func (void) { return X; }
389 then if you step into func<5>, "print X" will show "5". This
390 feature requires proper debuginfo support from the compiler; it
391 was added to GCC 4.5.
393 ** The motion commands "next", "finish", "until", and "advance" now
394 work better when exceptions are thrown. In particular, GDB will
395 no longer lose control of the inferior; instead, the GDB will
396 stop the inferior at the point at which the exception is caught.
397 This functionality requires a change in the exception handling
398 code that was introduced in GCC 4.5.
400 * GDB now follows GCC's rules on accessing volatile objects when
401 reading or writing target state during expression evaluation.
402 One notable difference to prior behavior is that "print x = 0"
403 no longer generates a read of x; the value of the assignment is
404 now always taken directly from the value being assigned.
406 * GDB now has some support for using labels in the program's source in
407 linespecs. For instance, you can use "advance label" to continue
408 execution to a label.
410 * GDB now has support for reading and writing a new .gdb_index
411 section. This section holds a fast index of DWARF debugging
412 information and can be used to greatly speed up GDB startup and
413 operation. See the documentation for `save gdb-index' for details.
415 * The "watch" command now accepts an optional "-location" argument.
416 When used, this causes GDB to watch the memory referred to by the
417 expression. Such a watchpoint is never deleted due to it going out
420 * GDB now supports thread debugging of core dumps on GNU/Linux.
422 GDB now activates thread debugging using the libthread_db library
423 when debugging GNU/Linux core dumps, similarly to when debugging
424 live processes. As a result, when debugging a core dump file, GDB
425 is now able to display pthread_t ids of threads. For example, "info
426 threads" shows the same output as when debugging the process when it
427 was live. In earlier releases, you'd see something like this:
430 * 1 LWP 6780 main () at main.c:10
432 While now you see this:
435 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
437 It is also now possible to inspect TLS variables when debugging core
440 When debugging a core dump generated on a machine other than the one
441 used to run GDB, you may need to point GDB at the correct
442 libthread_db library with the "set libthread-db-search-path"
443 command. See the user manual for more details on this command.
445 * When natively debugging programs on PowerPC BookE processors running
446 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
447 which stop execution of the inferior whenever it executes an instruction
448 at any address within the specified range. See the "PowerPC Embedded"
449 section in the user manual for more details.
451 * New features in the GDB remote stub, GDBserver
453 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
454 and i686 LynxOS (version 5.x).
456 ** GDBserver is now supported on Blackfin Linux.
458 * New native configurations
460 ia64 HP-UX ia64-*-hpux*
464 Analog Devices, Inc. Blackfin Processor bfin-*
466 * Ada task switching is now supported on sparc-elf targets when
467 debugging a program using the Ravenscar Profile. For more information,
468 see the "Tasking Support when using the Ravenscar Profile" section
469 in the GDB user manual.
471 * Guile support was removed.
473 * New features in the GNU simulator
475 ** The --map-info flag lists all known core mappings.
477 ** CFI flashes may be simulated via the "cfi" device.
479 *** Changes in GDB 7.2
481 * Shared library support for remote targets by default
483 When GDB is configured for a generic, non-OS specific target, like
484 for example, --target=arm-eabi or one of the many *-*-elf targets,
485 GDB now queries remote stubs for loaded shared libraries using the
486 `qXfer:libraries:read' packet. Previously, shared library support
487 was always disabled for such configurations.
491 ** Argument Dependent Lookup (ADL)
493 In C++ ADL lookup directs function search to the namespaces of its
494 arguments even if the namespace has not been imported.
504 Here the compiler will search for `foo' in the namespace of 'b'
505 and find A::foo. GDB now supports this. This construct is commonly
506 used in the Standard Template Library for operators.
508 ** Improved User Defined Operator Support
510 In addition to member operators, GDB now supports lookup of operators
511 defined in a namespace and imported with a `using' directive, operators
512 defined in the global scope, operators imported implicitly from an
513 anonymous namespace, and the ADL operators mentioned in the previous
515 GDB now also supports proper overload resolution for all the previously
516 mentioned flavors of operators.
518 ** static const class members
520 Printing of static const class members that are initialized in the
521 class definition has been fixed.
523 * Windows Thread Information Block access.
525 On Windows targets, GDB now supports displaying the Windows Thread
526 Information Block (TIB) structure. This structure is visible either
527 by using the new command `info w32 thread-information-block' or, by
528 dereferencing the new convenience variable named `$_tlb', a
529 thread-specific pointer to the TIB. This feature is also supported
530 when remote debugging using GDBserver.
534 Static tracepoints are calls in the user program into a tracing
535 library. One such library is a port of the LTTng kernel tracer to
536 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
537 When debugging with GDBserver, GDB now supports combining the GDB
538 tracepoint machinery with such libraries. For example: the user can
539 use GDB to probe a static tracepoint marker (a call from the user
540 program into the tracing library) with the new "strace" command (see
541 "New commands" below). This creates a "static tracepoint" in the
542 breakpoint list, that can be manipulated with the same feature set
543 as fast and regular tracepoints. E.g., collect registers, local and
544 global variables, collect trace state variables, and define
545 tracepoint conditions. In addition, the user can collect extra
546 static tracepoint marker specific data, by collecting the new
547 $_sdata internal variable. When analyzing the trace buffer, you can
548 inspect $_sdata like any other variable available to GDB. For more
549 information, see the "Tracepoints" chapter in GDB user manual. New
550 remote packets have been defined to support static tracepoints, see
551 the "New remote packets" section below.
553 * Better reconstruction of tracepoints after disconnected tracing
555 GDB will attempt to download the original source form of tracepoint
556 definitions when starting a trace run, and then will upload these
557 upon reconnection to the target, resulting in a more accurate
558 reconstruction of the tracepoints that are in use on the target.
562 You can now exercise direct control over the ways that GDB can
563 affect your program. For instance, you can disallow the setting of
564 breakpoints, so that the program can run continuously (assuming
565 non-stop mode). In addition, the "observer" variable is available
566 to switch all of the different controls; in observer mode, GDB
567 cannot affect the target's behavior at all, which is useful for
568 tasks like diagnosing live systems in the field.
570 * The new convenience variable $_thread holds the number of the
577 Return the address of the Windows Thread Information Block of a given thread.
581 In response to several of the tracepoint packets, the target may now
582 also respond with a number of intermediate `qRelocInsn' request
583 packets before the final result packet, to have GDB handle
584 relocating an instruction to execute at a different address. This
585 is particularly useful for stubs that support fast tracepoints. GDB
586 reports support for this feature in the qSupported packet.
590 List static tracepoint markers in the target program.
594 List static tracepoint markers at a given address in the target
597 qXfer:statictrace:read
599 Read the static trace data collected (by a `collect $_sdata'
600 tracepoint action). The remote stub reports support for this packet
601 to gdb's qSupported query.
605 Send the current settings of GDB's permission flags.
609 Send part of the source (textual) form of a tracepoint definition,
610 which includes location, conditional, and action list.
612 * The source command now accepts a -s option to force searching for the
613 script in the source search path even if the script name specifies
616 * New features in the GDB remote stub, GDBserver
618 - GDBserver now support tracepoints (including fast tracepoints, and
619 static tracepoints). The feature is currently supported by the
620 i386-linux and amd64-linux builds. See the "Tracepoints support
621 in gdbserver" section in the manual for more information.
623 GDBserver JIT compiles the tracepoint's conditional agent
624 expression bytecode into native code whenever possible for low
625 overhead dynamic tracepoints conditionals. For such tracepoints,
626 an expression that examines program state is evaluated when the
627 tracepoint is reached, in order to determine whether to capture
628 trace data. If the condition is simple and false, processing the
629 tracepoint finishes very quickly and no data is gathered.
631 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
632 for static tracepoints support.
634 - GDBserver now supports x86_64 Windows 64-bit debugging.
636 * GDB now sends xmlRegisters= in qSupported packet to indicate that
637 it understands register description.
639 * The --batch flag now disables pagination and queries.
641 * X86 general purpose registers
643 GDB now supports reading/writing byte, word and double-word x86
644 general purpose registers directly. This means you can use, say,
645 $ah or $ax to refer, respectively, to the byte register AH and
646 16-bit word register AX that are actually portions of the 32-bit
647 register EAX or 64-bit register RAX.
649 * The `commands' command now accepts a range of breakpoints to modify.
650 A plain `commands' following a command that creates multiple
651 breakpoints affects all the breakpoints set by that command. This
652 applies to breakpoints set by `rbreak', and also applies when a
653 single `break' command creates multiple breakpoints (e.g.,
654 breakpoints on overloaded c++ functions).
656 * The `rbreak' command now accepts a filename specification as part of
657 its argument, limiting the functions selected by the regex to those
658 in the specified file.
660 * Support for remote debugging Windows and SymbianOS shared libraries
661 from Unix hosts has been improved. Non Windows GDB builds now can
662 understand target reported file names that follow MS-DOS based file
663 system semantics, such as file names that include drive letters and
664 use the backslash character as directory separator. This makes it
665 possible to transparently use the "set sysroot" and "set
666 solib-search-path" on Unix hosts to point as host copies of the
667 target's shared libraries. See the new command "set
668 target-file-system-kind" described below, and the "Commands to
669 specify files" section in the user manual for more information.
673 eval template, expressions...
674 Convert the values of one or more expressions under the control
675 of the string template to a command line, and call it.
677 set target-file-system-kind unix|dos-based|auto
678 show target-file-system-kind
679 Set or show the assumed file system kind for target reported file
682 save breakpoints <filename>
683 Save all current breakpoint definitions to a file suitable for use
684 in a later debugging session. To read the saved breakpoint
685 definitions, use the `source' command.
687 `save tracepoints' is a new alias for `save-tracepoints'. The latter
690 info static-tracepoint-markers
691 Display information about static tracepoint markers in the target.
693 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
694 Define a static tracepoint by probing a marker at the given
695 function, line, address, or marker ID.
699 Enable and disable observer mode.
701 set may-write-registers on|off
702 set may-write-memory on|off
703 set may-insert-breakpoints on|off
704 set may-insert-tracepoints on|off
705 set may-insert-fast-tracepoints on|off
706 set may-interrupt on|off
707 Set individual permissions for GDB effects on the target. Note that
708 some of these settings can have undesirable or surprising
709 consequences, particularly when changed in the middle of a session.
710 For instance, disabling the writing of memory can prevent
711 breakpoints from being inserted, cause single-stepping to fail, or
712 even crash your program, if you disable after breakpoints have been
713 inserted. However, GDB should not crash.
715 set record memory-query on|off
716 show record memory-query
717 Control whether to stop the inferior if memory changes caused
718 by an instruction cannot be recorded.
723 The disassemble command now supports "start,+length" form of two arguments.
727 ** GDB now provides a new directory location, called the python directory,
728 where Python scripts written for GDB can be installed. The location
729 of that directory is <data-directory>/python, where <data-directory>
730 is the GDB data directory. For more details, see section `Scripting
731 GDB using Python' in the manual.
733 ** The GDB Python API now has access to breakpoints, symbols, symbol
734 tables, program spaces, inferiors, threads and frame's code blocks.
735 Additionally, GDB Parameters can now be created from the API, and
736 manipulated via set/show in the CLI.
738 ** New functions gdb.target_charset, gdb.target_wide_charset,
739 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
741 ** New exception gdb.GdbError.
743 ** Pretty-printers are now also looked up in the current program space.
745 ** Pretty-printers can now be individually enabled and disabled.
747 ** GDB now looks for names of Python scripts to auto-load in a
748 special section named `.debug_gdb_scripts', in addition to looking
749 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
751 * Tracepoint actions were unified with breakpoint commands. In particular,
752 there are no longer differences in "info break" output for breakpoints and
753 tracepoints and the "commands" command can be used for both tracepoints and
758 ARM Symbian arm*-*-symbianelf*
760 * D language support.
761 GDB now supports debugging programs written in the D programming
764 * GDB now supports the extended ptrace interface for PowerPC which is
765 available since Linux kernel version 2.6.34. This automatically enables
766 any hardware breakpoints and additional hardware watchpoints available in
767 the processor. The old ptrace interface exposes just one hardware
768 watchpoint and no hardware breakpoints.
770 * GDB is now able to use the Data Value Compare (DVC) register available on
771 embedded PowerPC processors to implement in hardware simple watchpoint
772 conditions of the form:
774 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
776 This works in native GDB running on Linux kernels with the extended ptrace
777 interface mentioned above.
779 *** Changes in GDB 7.1
785 GDB now supports importing of namespaces in C++. This enables the
786 user to inspect variables from imported namespaces. Support for
787 namepace aliasing has also been added. So, if a namespace is
788 aliased in the current scope (e.g. namepace C=A; ) the user can
789 print variables using the alias (e.g. (gdb) print C::x).
793 All known bugs relating to the printing of virtual base class were
794 fixed. It is now possible to call overloaded static methods using a
799 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
800 and reinterpret_cast<> are now handled by the C++ expression parser.
804 Xilinx MicroBlaze microblaze-*-*
809 Xilinx MicroBlaze microblaze
812 * Multi-program debugging.
814 GDB now has support for multi-program (a.k.a. multi-executable or
815 multi-exec) debugging. This allows for debugging multiple inferiors
816 simultaneously each running a different program under the same GDB
817 session. See "Debugging Multiple Inferiors and Programs" in the
818 manual for more information. This implied some user visible changes
819 in the multi-inferior support. For example, "info inferiors" now
820 lists inferiors that are not running yet or that have exited
821 already. See also "New commands" and "New options" below.
823 * New tracing features
825 GDB's tracepoint facility now includes several new features:
827 ** Trace state variables
829 GDB tracepoints now include support for trace state variables, which
830 are variables managed by the target agent during a tracing
831 experiment. They are useful for tracepoints that trigger each
832 other, so for instance one tracepoint can count hits in a variable,
833 and then a second tracepoint has a condition that is true when the
834 count reaches a particular value. Trace state variables share the
835 $-syntax of GDB convenience variables, and can appear in both
836 tracepoint actions and condition expressions. Use the "tvariable"
837 command to create, and "info tvariables" to view; see "Trace State
838 Variables" in the manual for more detail.
842 GDB now includes an option for defining fast tracepoints, which
843 targets may implement more efficiently, such as by installing a jump
844 into the target agent rather than a trap instruction. The resulting
845 speedup can be by two orders of magnitude or more, although the
846 tradeoff is that some program locations on some target architectures
847 might not allow fast tracepoint installation, for instance if the
848 instruction to be replaced is shorter than the jump. To request a
849 fast tracepoint, use the "ftrace" command, with syntax identical to
850 the regular trace command.
852 ** Disconnected tracing
854 It is now possible to detach GDB from the target while it is running
855 a trace experiment, then reconnect later to see how the experiment
856 is going. In addition, a new variable disconnected-tracing lets you
857 tell the target agent whether to continue running a trace if the
858 connection is lost unexpectedly.
862 GDB now has the ability to save the trace buffer into a file, and
863 then use that file as a target, similarly to you can do with
864 corefiles. You can select trace frames, print data that was
865 collected in them, and use tstatus to display the state of the
866 tracing run at the moment that it was saved. To create a trace
867 file, use "tsave <filename>", and to use it, do "target tfile
870 ** Circular trace buffer
872 You can ask the target agent to handle the trace buffer as a
873 circular buffer, discarding the oldest trace frames to make room for
874 newer ones, by setting circular-trace-buffer to on. This feature may
875 not be available for all target agents.
880 The disassemble command, when invoked with two arguments, now requires
881 the arguments to be comma-separated.
884 The info variables command now displays variable definitions. Files
885 which only declare a variable are not shown.
888 The source command is now capable of sourcing Python scripts.
889 This feature is dependent on the debugger being build with Python
892 Related to this enhancement is also the introduction of a new command
893 "set script-extension" (see below).
895 * New commands (for set/show, see "New options" below)
897 record save [<FILENAME>]
898 Save a file (in core file format) containing the process record
899 execution log for replay debugging at a later time.
901 record restore <FILENAME>
902 Restore the process record execution log that was saved at an
903 earlier time, for replay debugging.
905 add-inferior [-copies <N>] [-exec <FILENAME>]
908 clone-inferior [-copies <N>] [ID]
909 Make a new inferior ready to execute the same program another
915 maint info program-spaces
916 List the program spaces loaded into GDB.
918 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
919 show remote interrupt-sequence
920 Allow the user to select one of ^C, a BREAK signal or BREAK-g
921 as the sequence to the remote target in order to interrupt the execution.
922 Ctrl-C is a default. Some system prefers BREAK which is high level of
923 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
924 Magic SysRq g. It is BREAK signal and character 'g'.
926 set remote interrupt-on-connect [on | off]
927 show remote interrupt-on-connect
928 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
929 remote target when gdb connects to it. This is needed when you debug
932 set remotebreak [on | off]
934 Deprecated. Use "set/show remote interrupt-sequence" instead.
936 tvariable $NAME [ = EXP ]
937 Create or modify a trace state variable.
940 List trace state variables and their values.
942 delete tvariable $NAME ...
943 Delete one or more trace state variables.
946 Evaluate the given expressions without collecting anything into the
947 trace buffer. (Valid in tracepoint actions only.)
949 ftrace FN / FILE:LINE / *ADDR
950 Define a fast tracepoint at the given function, line, or address.
952 * New expression syntax
954 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
955 GDB now parses 0b101010 identically with 42.
959 set follow-exec-mode new|same
960 show follow-exec-mode
961 Control whether GDB reuses the same inferior across an exec call or
962 creates a new one. This is useful to be able to restart the old
963 executable after the inferior having done an exec call.
965 set default-collect EXPR, ...
967 Define a list of expressions to be collected at each tracepoint.
968 This is a useful way to ensure essential items are not overlooked,
969 such as registers or a critical global variable.
971 set disconnected-tracing
972 show disconnected-tracing
973 If set to 1, the target is instructed to continue tracing if it
974 loses its connection to GDB. If 0, the target is to stop tracing
977 set circular-trace-buffer
978 show circular-trace-buffer
979 If set to on, the target is instructed to use a circular trace buffer
980 and discard the oldest trace frames instead of stopping the trace due
981 to a full trace buffer. If set to off, the trace stops when the buffer
982 fills up. Some targets may not support this.
984 set script-extension off|soft|strict
985 show script-extension
986 If set to "off", the debugger does not perform any script language
987 recognition, and all sourced files are assumed to be GDB scripts.
988 If set to "soft" (the default), files are sourced according to
989 filename extension, falling back to GDB scripts if the first
991 If set to "strict", files are sourced according to filename extension.
993 set ada trust-PAD-over-XVS on|off
994 show ada trust-PAD-over-XVS
995 If off, activate a workaround against a bug in the debugging information
996 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
997 the GCC sources for more information about the GNAT encoding and
998 PAD types in particular). It is always safe to set this option to
999 off, but this introduces a slight performance penalty. The default
1002 * Python API Improvements
1004 ** GDB provides the new class gdb.LazyString. This is useful in
1005 some pretty-printing cases. The new method gdb.Value.lazy_string
1006 provides a simple way to create objects of this type.
1008 ** The fields returned by gdb.Type.fields now have an
1009 `is_base_class' attribute.
1011 ** The new method gdb.Type.range returns the range of an array type.
1013 ** The new method gdb.parse_and_eval can be used to parse and
1014 evaluate an expression.
1016 * New remote packets
1019 Define a trace state variable.
1022 Get the current value of a trace state variable.
1025 Set desired tracing behavior upon disconnection.
1028 Set the trace buffer to be linear or circular.
1031 Get data about the tracepoints currently in use.
1035 Process record now works correctly with hardware watchpoints.
1037 Multiple bug fixes have been made to the mips-irix port, making it
1038 much more reliable. In particular:
1039 - Debugging threaded applications is now possible again. Previously,
1040 GDB would hang while starting the program, or while waiting for
1041 the program to stop at a breakpoint.
1042 - Attaching to a running process no longer hangs.
1043 - An error occurring while loading a core file has been fixed.
1044 - Changing the value of the PC register now works again. This fixes
1045 problems observed when using the "jump" command, or when calling
1046 a function from GDB, or even when assigning a new value to $pc.
1047 - With the "finish" and "return" commands, the return value for functions
1048 returning a small array is now correctly printed.
1049 - It is now possible to break on shared library code which gets executed
1050 during a shared library init phase (code executed while executing
1051 their .init section). Previously, the breakpoint would have no effect.
1052 - GDB is now able to backtrace through the signal handler for
1053 non-threaded programs.
1055 PIE (Position Independent Executable) programs debugging is now supported.
1056 This includes debugging execution of PIC (Position Independent Code) shared
1057 libraries although for that, it should be possible to run such libraries as an
1060 *** Changes in GDB 7.0
1062 * GDB now has an interface for JIT compilation. Applications that
1063 dynamically generate code can create symbol files in memory and register
1064 them with GDB. For users, the feature should work transparently, and
1065 for JIT developers, the interface is documented in the GDB manual in the
1066 "JIT Compilation Interface" chapter.
1068 * Tracepoints may now be conditional. The syntax is as for
1069 breakpoints; either an "if" clause appended to the "trace" command,
1070 or the "condition" command is available. GDB sends the condition to
1071 the target for evaluation using the same bytecode format as is used
1072 for tracepoint actions.
1074 * The disassemble command now supports: an optional /r modifier, print the
1075 raw instructions in hex as well as in symbolic form, and an optional /m
1076 modifier to print mixed source+assembly.
1078 * Process record and replay
1080 In a architecture environment that supports ``process record and
1081 replay'', ``process record and replay'' target can record a log of
1082 the process execution, and replay it with both forward and reverse
1085 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1086 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1087 set execution-direction {forward|reverse}, for targets that support
1090 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1091 feature is available with a native GDB running on kernel version
1094 * GDB now has support for multi-byte and wide character sets on the
1095 target. Strings whose character type is wchar_t, char16_t, or
1096 char32_t are now correctly printed. GDB supports wide- and unicode-
1097 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1098 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1099 `printf'. This feature requires iconv to work properly; if your
1100 system does not have a working iconv, GDB can use GNU libiconv. See
1101 the installation instructions for more information.
1103 * GDB now supports automatic retrieval of shared library files from
1104 remote targets. To use this feature, specify a system root that begins
1105 with the `remote:' prefix, either via the `set sysroot' command or via
1106 the `--with-sysroot' configure-time option.
1108 * "info sharedlibrary" now takes an optional regex of libraries to show,
1109 and it now reports if a shared library has no debugging information.
1111 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1112 now complete on file names.
1114 * When completing in expressions, gdb will attempt to limit
1115 completions to allowable structure or union fields, where appropriate.
1116 For instance, consider:
1118 # struct example { int f1; double f2; };
1119 # struct example variable;
1122 If the user types TAB at the end of this command line, the available
1123 completions will be "f1" and "f2".
1125 * Inlined functions are now supported. They show up in backtraces, and
1126 the "step", "next", and "finish" commands handle them automatically.
1128 * GDB now supports the token-splicing (##) and stringification (#)
1129 operators when expanding macros. It also supports variable-arity
1132 * GDB now supports inspecting extra signal information, exported by
1133 the new $_siginfo convenience variable. The feature is currently
1134 implemented on linux ARM, i386 and amd64.
1136 * GDB can now display the VFP floating point registers and NEON vector
1137 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1138 can provide these registers (requires Linux 2.6.30 or later). Remote
1139 and simulator targets may also provide them.
1141 * New remote packets
1144 Search memory for a sequence of bytes.
1147 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1148 operation over reliable transport links. Use of this packet is
1149 controlled by the `set remote noack-packet' command.
1152 Kill the process with the specified process ID. Use this in preference
1153 to `k' when multiprocess protocol extensions are supported.
1156 Obtains additional operating system information
1160 Read or write additional signal information.
1162 * Removed remote protocol undocumented extension
1164 An undocumented extension to the remote protocol's `S' stop reply
1165 packet that permited the stub to pass a process id was removed.
1166 Remote servers should use the `T' stop reply packet instead.
1168 * GDB now supports multiple function calling conventions according to the
1169 DWARF-2 DW_AT_calling_convention function attribute.
1171 * The SH target utilizes the aforementioned change to distinguish between gcc
1172 and Renesas calling convention. It also adds the new CLI commands
1173 `set/show sh calling-convention'.
1175 * GDB can now read compressed debug sections, as produced by GNU gold
1176 with the --compress-debug-sections=zlib flag.
1178 * 64-bit core files are now supported on AIX.
1180 * Thread switching is now supported on Tru64.
1182 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1183 which will be allocated using malloc later in program execution.
1185 * The qXfer:libraries:read remote procotol packet now allows passing a
1186 list of section offsets.
1188 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1189 conditions handling signals delivered during attach or thread creation
1190 have also been fixed.
1192 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1193 From the user's standpoint, all unqualified instances of True and False
1194 are treated as the standard definitions, regardless of context.
1196 * GDB now parses C++ symbol and type names more flexibly. For
1199 template<typename T> class C { };
1202 GDB will now correctly handle all of:
1204 ptype C<char const *>
1205 ptype C<char const*>
1206 ptype C<const char *>
1207 ptype C<const char*>
1209 * New features in the GDB remote stub, gdbserver
1211 - The "--wrapper" command-line argument tells gdbserver to use a
1212 wrapper program to launch programs for debugging.
1214 - On PowerPC and S/390 targets, it is now possible to use a single
1215 gdbserver executable to debug both 32-bit and 64-bit programs.
1216 (This requires gdbserver itself to be built as a 64-bit executable.)
1218 - gdbserver uses the new noack protocol mode for TCP connections to
1219 reduce communications latency, if also supported and enabled in GDB.
1221 - Support for the sparc64-linux-gnu target is now included in
1224 - The amd64-linux build of gdbserver now supports debugging both
1225 32-bit and 64-bit programs.
1227 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1228 now support hardware watchpoints, and will use them automatically
1233 GDB now has support for scripting using Python. Whether this is
1234 available is determined at configure time.
1236 New GDB commands can now be written in Python.
1238 * Ada tasking support
1240 Ada tasks can now be inspected in GDB. The following commands have
1244 Print the list of Ada tasks.
1246 Print detailed information about task number N.
1248 Print the task number of the current task.
1250 Switch the context of debugging to task number N.
1252 * Support for user-defined prefixed commands. The "define" command can
1253 add new commands to existing prefixes, e.g. "target".
1255 * Multi-inferior, multi-process debugging.
1257 GDB now has generalized support for multi-inferior debugging. See
1258 "Debugging Multiple Inferiors" in the manual for more information.
1259 Although availability still depends on target support, the command
1260 set is more uniform now. The GNU/Linux specific multi-forks support
1261 has been migrated to this new framework. This implied some user
1262 visible changes; see "New commands" and also "Removed commands"
1265 * Target descriptions can now describe the target OS ABI. See the
1266 "Target Description Format" section in the user manual for more
1269 * Target descriptions can now describe "compatible" architectures
1270 to indicate that the target can execute applications for a different
1271 architecture in addition to those for the main target architecture.
1272 See the "Target Description Format" section in the user manual for
1275 * Multi-architecture debugging.
1277 GDB now includes general supports for debugging applications on
1278 hybrid systems that use more than one single processor architecture
1279 at the same time. Each such hybrid architecture still requires
1280 specific support to be added. The only hybrid architecture supported
1281 in this version of GDB is the Cell Broadband Engine.
1283 * GDB now supports integrated debugging of Cell/B.E. applications that
1284 use both the PPU and SPU architectures. To enable support for hybrid
1285 Cell/B.E. debugging, you need to configure GDB to support both the
1286 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1287 --enable-targets configure option.
1289 * Non-stop mode debugging.
1291 For some targets, GDB now supports an optional mode of operation in
1292 which you can examine stopped threads while other threads continue
1293 to execute freely. This is referred to as non-stop mode, with the
1294 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1295 section in the user manual for more information.
1297 To be able to support remote non-stop debugging, a remote stub needs
1298 to implement the non-stop mode remote protocol extensions, as
1299 described in the "Remote Non-Stop" section of the user manual. The
1300 GDB remote stub, gdbserver, has been adjusted to support these
1301 extensions on linux targets.
1303 * New commands (for set/show, see "New options" below)
1305 catch syscall [NAME(S) | NUMBER(S)]
1306 Catch system calls. Arguments, which should be names of system
1307 calls or their numbers, mean catch only those syscalls. Without
1308 arguments, every syscall will be caught. When the inferior issues
1309 any of the specified syscalls, GDB will stop and announce the system
1310 call, both when it is called and when its call returns. This
1311 feature is currently available with a native GDB running on the
1312 Linux Kernel, under the following architectures: x86, x86_64,
1313 PowerPC and PowerPC64.
1315 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1317 Search memory for a sequence of bytes.
1319 maint set python print-stack
1320 maint show python print-stack
1321 Show a stack trace when an error is encountered in a Python script.
1324 Invoke CODE by passing it to the Python interpreter.
1329 These allow macros to be defined, undefined, and listed
1333 Show operating system information about processes.
1336 List the inferiors currently under GDB's control.
1339 Switch focus to inferior number NUM.
1342 Detach from inferior number NUM.
1345 Kill inferior number NUM.
1349 set spu stop-on-load
1350 show spu stop-on-load
1351 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1353 set spu auto-flush-cache
1354 show spu auto-flush-cache
1355 Control whether to automatically flush the software-managed cache
1356 during Cell/B.E. debugging.
1358 set sh calling-convention
1359 show sh calling-convention
1360 Control the calling convention used when calling SH target functions.
1363 show debug timestamp
1364 Control display of timestamps with GDB debugging output.
1366 set disassemble-next-line
1367 show disassemble-next-line
1368 Control display of disassembled source lines or instructions when
1371 set remote noack-packet
1372 show remote noack-packet
1373 Set/show the use of remote protocol QStartNoAckMode packet. See above
1374 under "New remote packets."
1376 set remote query-attached-packet
1377 show remote query-attached-packet
1378 Control use of remote protocol `qAttached' (query-attached) packet.
1380 set remote read-siginfo-object
1381 show remote read-siginfo-object
1382 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1385 set remote write-siginfo-object
1386 show remote write-siginfo-object
1387 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1390 set remote reverse-continue
1391 show remote reverse-continue
1392 Control use of remote protocol 'bc' (reverse-continue) packet.
1394 set remote reverse-step
1395 show remote reverse-step
1396 Control use of remote protocol 'bs' (reverse-step) packet.
1398 set displaced-stepping
1399 show displaced-stepping
1400 Control displaced stepping mode. Displaced stepping is a way to
1401 single-step over breakpoints without removing them from the debuggee.
1402 Also known as "out-of-line single-stepping".
1405 show debug displaced
1406 Control display of debugging info for displaced stepping.
1408 maint set internal-error
1409 maint show internal-error
1410 Control what GDB does when an internal error is detected.
1412 maint set internal-warning
1413 maint show internal-warning
1414 Control what GDB does when an internal warning is detected.
1419 Use a wrapper program to launch programs for debugging.
1421 set multiple-symbols (all|ask|cancel)
1422 show multiple-symbols
1423 The value of this variable can be changed to adjust the debugger behavior
1424 when an expression or a breakpoint location contains an ambiguous symbol
1425 name (an overloaded function name, for instance).
1427 set breakpoint always-inserted
1428 show breakpoint always-inserted
1429 Keep breakpoints always inserted in the target, as opposed to inserting
1430 them when resuming the target, and removing them when the target stops.
1431 This option can improve debugger performance on slow remote targets.
1433 set arm fallback-mode (arm|thumb|auto)
1434 show arm fallback-mode
1435 set arm force-mode (arm|thumb|auto)
1437 These commands control how ARM GDB determines whether instructions
1438 are ARM or Thumb. The default for both settings is auto, which uses
1439 the current CPSR value for instructions without symbols; previous
1440 versions of GDB behaved as if "set arm fallback-mode arm".
1442 set disable-randomization
1443 show disable-randomization
1444 Standalone programs run with the virtual address space randomization enabled
1445 by default on some platforms. This option keeps the addresses stable across
1446 multiple debugging sessions.
1450 Control whether other threads are stopped or not when some thread hits
1455 Requests that asynchronous execution is enabled in the target, if available.
1456 In this case, it's possible to resume target in the background, and interact
1457 with GDB while the target is running. "show target-async" displays the
1458 current state of asynchronous execution of the target.
1460 set target-wide-charset
1461 show target-wide-charset
1462 The target-wide-charset is the name of the character set that GDB
1463 uses when printing characters whose type is wchar_t.
1465 set tcp auto-retry (on|off)
1467 set tcp connect-timeout
1468 show tcp connect-timeout
1469 These commands allow GDB to retry failed TCP connections to a remote stub
1470 with a specified timeout period; this is useful if the stub is launched
1471 in parallel with GDB but may not be ready to accept connections immediately.
1473 set libthread-db-search-path
1474 show libthread-db-search-path
1475 Control list of directories which GDB will search for appropriate
1478 set schedule-multiple (on|off)
1479 show schedule-multiple
1480 Allow GDB to resume all threads of all processes or only threads of
1481 the current process.
1485 Use more aggressive caching for accesses to the stack. This improves
1486 performance of remote debugging (particularly backtraces) without
1487 affecting correctness.
1489 set interactive-mode (on|off|auto)
1490 show interactive-mode
1491 Control whether GDB runs in interactive mode (on) or not (off).
1492 When in interactive mode, GDB waits for the user to answer all
1493 queries. Otherwise, GDB does not wait and assumes the default
1494 answer. When set to auto (the default), GDB determines which
1495 mode to use based on the stdin settings.
1500 For program forks, this is replaced by the new more generic `info
1501 inferiors' command. To list checkpoints, you can still use the
1502 `info checkpoints' command, which was an alias for the `info forks'
1506 Replaced by the new `inferior' command. To switch between
1507 checkpoints, you can still use the `restart' command, which was an
1508 alias for the `fork' command.
1511 This is removed, since some targets don't have a notion of
1512 processes. To switch between processes, you can still use the
1513 `inferior' command using GDB's own inferior number.
1516 For program forks, this is replaced by the new more generic `kill
1517 inferior' command. To delete a checkpoint, you can still use the
1518 `delete checkpoint' command, which was an alias for the `delete
1522 For program forks, this is replaced by the new more generic `detach
1523 inferior' command. To detach a checkpoint, you can still use the
1524 `detach checkpoint' command, which was an alias for the `detach
1527 * New native configurations
1529 x86/x86_64 Darwin i[34567]86-*-darwin*
1531 x86_64 MinGW x86_64-*-mingw*
1535 Lattice Mico32 lm32-*
1536 x86 DICOS i[34567]86-*-dicos*
1537 x86_64 DICOS x86_64-*-dicos*
1540 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1541 (mingw32ce) debugging.
1547 These commands were actually not implemented on any target.
1549 *** Changes in GDB 6.8
1551 * New native configurations
1553 NetBSD/hppa hppa*-*netbsd*
1554 Xtensa GNU/Linux xtensa*-*-linux*
1558 NetBSD/hppa hppa*-*-netbsd*
1559 Xtensa GNU/Lunux xtensa*-*-linux*
1561 * Change in command line behavior -- corefiles vs. process ids.
1563 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1564 attaching to process NUMBER fails, GDB no longer attempts to open a
1565 core file named NUMBER. Attaching to a program using the -c option
1566 is no longer supported. Instead, use the '-p' or '--pid' options.
1568 * GDB can now be built as a native debugger for debugging Windows x86
1569 (mingw32) Portable Executable (PE) programs.
1571 * Pending breakpoints no longer change their number when their address
1574 * GDB now supports breakpoints with multiple locations,
1575 including breakpoints on C++ constructors, inside C++ templates,
1576 and in inlined functions.
1578 * GDB's ability to debug optimized code has been improved. GDB more
1579 accurately identifies function bodies and lexical blocks that occupy
1580 more than one contiguous range of addresses.
1582 * Target descriptions can now describe registers for PowerPC.
1584 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1585 registers on PowerPC targets.
1587 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1588 targets even when the libthread_db library is not available.
1590 * The GDB remote stub, gdbserver, now supports the new file transfer
1591 commands (remote put, remote get, and remote delete).
1593 * The GDB remote stub, gdbserver, now supports run and attach in
1594 extended-remote mode.
1596 * hppa*64*-*-hpux11* target broken
1597 The debugger is unable to start a program and fails with the following
1598 error: "Error trying to get information about dynamic linker".
1599 The gdb-6.7 release is also affected.
1601 * GDB now supports the --enable-targets= configure option to allow
1602 building a single GDB executable that supports multiple remote
1603 target architectures.
1605 * GDB now supports debugging C and C++ programs which use the
1606 Decimal Floating Point extension. In addition, the PowerPC target
1607 now has a set of pseudo-registers to inspect decimal float values
1608 stored in two consecutive float registers.
1610 * The -break-insert MI command can optionally create pending
1613 * Improved support for debugging Ada
1614 Many improvements to the Ada language support have been made. These
1616 - Better support for Ada2005 interface types
1617 - Improved handling of arrays and slices in general
1618 - Better support for Taft-amendment types
1619 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1621 - Improved command completion in Ada
1624 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1629 set print frame-arguments (all|scalars|none)
1630 show print frame-arguments
1631 The value of this variable can be changed to control which argument
1632 values should be printed by the debugger when displaying a frame.
1637 Transfer files to and from a remote target, and delete remote files.
1644 Transfer files to and from a remote target, and delete remote files.
1646 * New remote packets
1653 Open, close, read, write, and delete files on the remote system.
1656 Attach to an existing process on the remote system, in extended-remote
1660 Run a new process on the remote system, in extended-remote mode.
1662 *** Changes in GDB 6.7
1664 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1665 bfd, libiberty and opcodes, as revealed by static analysis donated by
1666 Coverity, Inc. (http://scan.coverity.com).
1668 * When looking up multiply-defined global symbols, GDB will now prefer the
1669 symbol definition in the current shared library if it was built using the
1670 -Bsymbolic linker option.
1672 * When the Text User Interface (TUI) is not configured, GDB will now
1673 recognize the -tui command-line option and print a message that the TUI
1676 * The GDB remote stub, gdbserver, now has lower overhead for high
1677 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1679 * GDB for MIPS targets now autodetects whether a remote target provides
1680 32-bit or 64-bit register values.
1682 * Support for C++ member pointers has been improved.
1684 * GDB now understands XML target descriptions, which specify the
1685 target's overall architecture. GDB can read a description from
1686 a local file or over the remote serial protocol.
1688 * Vectors of single-byte data use a new integer type which is not
1689 automatically displayed as character or string data.
1691 * The /s format now works with the print command. It displays
1692 arrays of single-byte integers and pointers to single-byte integers
1695 * Target descriptions can now describe target-specific registers,
1696 for architectures which have implemented the support (currently
1697 only ARM, M68K, and MIPS).
1699 * GDB and the GDB remote stub, gdbserver, now support the XScale
1702 * The GDB remote stub, gdbserver, has been updated to support
1703 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1704 has been rewritten to use the standard GDB remote protocol.
1706 * GDB can now step into C++ functions which are called through thunks.
1708 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1710 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1711 layout. It also supports a TextSeg= and DataSeg= response when only
1712 segment base addresses (rather than offsets) are available.
1714 * The /i format now outputs any trailing branch delay slot instructions
1715 immediately following the last instruction within the count specified.
1717 * The GDB remote protocol "T" stop reply packet now supports a
1718 "library" response. Combined with the new "qXfer:libraries:read"
1719 packet, this response allows GDB to debug shared libraries on targets
1720 where the operating system manages the list of loaded libraries (e.g.
1721 Windows and SymbianOS).
1723 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1724 (DLLs) on Windows and Windows CE targets.
1726 * GDB now supports a faster verification that a .debug file matches its binary
1727 according to its build-id signature, if the signature is present.
1733 Enable or disable hardware flow control (RTS/CTS) on the serial port
1734 when debugging using remote targets.
1736 set mem inaccessible-by-default
1737 show mem inaccessible-by-default
1738 If the target supplies a memory map, for instance via the remote
1739 protocol's "qXfer:memory-map:read" packet, setting this variable
1740 prevents GDB from accessing memory outside the memory map. This
1741 is useful for targets with memory mapped registers or which react
1742 badly to accesses of unmapped address space.
1744 set breakpoint auto-hw
1745 show breakpoint auto-hw
1746 If the target supplies a memory map, for instance via the remote
1747 protocol's "qXfer:memory-map:read" packet, setting this variable
1748 lets GDB use hardware breakpoints automatically for memory regions
1749 where it can not use software breakpoints. This covers both the
1750 "break" command and internal breakpoints used for other commands
1751 including "next" and "finish".
1754 catch exception unhandled
1755 Stop the program execution when Ada exceptions are raised.
1758 Stop the program execution when an Ada assertion failed.
1762 Set an alternate system root for target files. This is a more
1763 general version of "set solib-absolute-prefix", which is now
1764 an alias to "set sysroot".
1767 Provide extended SPU facility status information. This set of
1768 commands is available only when debugging the Cell/B.E. SPU
1771 * New native configurations
1773 OpenBSD/sh sh*-*openbsd*
1776 unset tdesc filename
1778 Use the specified local file as an XML target description, and do
1779 not query the target for its built-in description.
1783 OpenBSD/sh sh*-*-openbsd*
1784 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1785 Toshiba Media Processor mep-elf
1787 * New remote packets
1790 Ignore the specified signals; pass them directly to the debugged program
1791 without stopping other threads or reporting them to GDB.
1793 qXfer:features:read:
1794 Read an XML target description from the target, which describes its
1799 Read or write contents of an spufs file on the target system. These
1800 packets are available only on the Cell/B.E. SPU architecture.
1802 qXfer:libraries:read:
1803 Report the loaded shared libraries. Combined with new "T" packet
1804 response, this packet allows GDB to debug shared libraries on
1805 targets where the operating system manages the list of loaded
1806 libraries (e.g. Windows and SymbianOS).
1810 Support for these obsolete configurations has been removed.
1818 i[34567]86-*-lynxos*
1819 i[34567]86-*-netware*
1820 i[34567]86-*-sco3.2v5*
1821 i[34567]86-*-sco3.2v4*
1823 i[34567]86-*-sysv4.2*
1826 i[34567]86-*-unixware2*
1827 i[34567]86-*-unixware*
1836 * Other removed features
1843 Various m68k-only ROM monitors.
1850 Various Renesas ROM monitors and debugging interfaces for SH and
1855 Support for a Macraigor serial interface to on-chip debugging.
1856 GDB does not directly support the newer parallel or USB
1861 A debug information format. The predecessor to DWARF 2 and
1862 DWARF 3, which are still supported.
1864 Support for the HP aCC compiler on HP-UX/PA-RISC
1866 SOM-encapsulated symbolic debugging information, automatic
1867 invocation of pxdb, and the aCC custom C++ ABI. This does not
1868 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1869 with aCC can still be debugged on an assembly level.
1871 MIPS ".pdr" sections
1873 A MIPS-specific format used to describe stack frame layout
1874 in debugging information.
1878 GDB could work with an older version of Guile to debug
1879 the interpreter and Scheme programs running in it.
1881 set mips stack-arg-size
1882 set mips saved-gpreg-size
1884 Use "set mips abi" to control parameter passing for MIPS.
1886 *** Changes in GDB 6.6
1891 Cell Broadband Engine SPU spu-elf
1893 * GDB can now be configured as a cross-debugger targeting native Windows
1894 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1895 running on a Windows system over TCP/IP to debug Windows programs.
1897 * The GDB remote stub, gdbserver, has been updated to support Windows and
1898 Cygwin debugging. Both single-threaded and multi-threaded programs are
1901 * The "set trust-readonly-sections" command works again. This command was
1902 broken in GDB 6.3, 6.4, and 6.5.
1904 * The "load" command now supports writing to flash memory, if the remote
1905 stub provides the required support.
1907 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1908 longer requires symbolic debug information (e.g. DWARF-2).
1913 unset substitute-path
1914 show substitute-path
1915 Manage a list of substitution rules that GDB uses to rewrite the name
1916 of the directories where the sources are located. This can be useful
1917 for instance when the sources were moved to a different location
1918 between compilation and debugging.
1922 Print each CLI command as it is executed. Each command is prefixed with
1923 a number of `+' symbols representing the nesting depth.
1924 The source command now has a `-v' option to enable the same feature.
1928 The ARM Demon monitor support (RDP protocol, "target rdp").
1930 Kernel Object Display, an embedded debugging feature which only worked with
1931 an obsolete version of Cisco IOS.
1933 The 'set download-write-size' and 'show download-write-size' commands.
1935 * New remote packets
1938 Tell a stub about GDB client features, and request remote target features.
1939 The first feature implemented is PacketSize, which allows the target to
1940 specify the size of packets it can handle - to minimize the number of
1941 packets required and improve performance when connected to a remote
1945 Fetch an OS auxilliary vector from the remote stub. This packet is a
1946 more efficient replacement for qPart:auxv:read.
1948 qXfer:memory-map:read:
1949 Fetch a memory map from the remote stub, including information about
1950 RAM, ROM, and flash memory devices.
1955 Erase and program a flash memory device.
1957 * Removed remote packets
1960 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1961 used it, and only gdbserver implemented it.
1963 *** Changes in GDB 6.5
1967 Renesas M32C/M16C m32c-elf
1969 Morpho Technologies ms1 ms1-elf
1973 init-if-undefined Initialize a convenience variable, but
1974 only if it doesn't already have a value.
1976 The following commands are presently only implemented for native GNU/Linux:
1978 checkpoint Save a snapshot of the program state.
1980 restart <n> Return the program state to a
1981 previously saved state.
1983 info checkpoints List currently saved checkpoints.
1985 delete-checkpoint <n> Delete a previously saved checkpoint.
1987 set|show detach-on-fork Tell gdb whether to detach from a newly
1988 forked process, or to keep debugging it.
1990 info forks List forks of the user program that
1991 are available to be debugged.
1993 fork <n> Switch to debugging one of several
1994 forks of the user program that are
1995 available to be debugged.
1997 delete-fork <n> Delete a fork from the list of forks
1998 that are available to be debugged (and
1999 kill the forked process).
2001 detach-fork <n> Delete a fork from the list of forks
2002 that are available to be debugged (and
2003 allow the process to continue).
2007 Morpho Technologies ms2 ms1-elf
2009 * Improved Windows host support
2011 GDB now builds as a cross debugger hosted on i686-mingw32, including
2012 native console support, and remote communications using either
2013 network sockets or serial ports.
2015 * Improved Modula-2 language support
2017 GDB can now print most types in the Modula-2 syntax. This includes:
2018 basic types, set types, record types, enumerated types, range types,
2019 pointer types and ARRAY types. Procedure var parameters are correctly
2020 printed and hexadecimal addresses and character constants are also
2021 written in the Modula-2 syntax. Best results can be obtained by using
2022 GNU Modula-2 together with the -gdwarf-2 command line option.
2026 The ARM rdi-share module.
2028 The Netware NLM debug server.
2030 *** Changes in GDB 6.4
2032 * New native configurations
2034 OpenBSD/arm arm*-*-openbsd*
2035 OpenBSD/mips64 mips64-*-openbsd*
2039 Morpho Technologies ms1 ms1-elf
2041 * New command line options
2043 --batch-silent As for --batch, but totally silent.
2044 --return-child-result The debugger will exist with the same value
2045 the child (debugged) program exited with.
2046 --eval-command COMMAND, -ex COMMAND
2047 Execute a single GDB CLI command. This may be
2048 specified multiple times and in conjunction
2049 with the --command (-x) option.
2051 * Deprecated commands removed
2053 The following commands, that were deprecated in 2000, have been
2057 set|show arm disassembly-flavor set|show arm disassembler
2058 othernames set arm disassembler
2059 set|show remotedebug set|show debug remote
2060 set|show archdebug set|show debug arch
2061 set|show eventdebug set|show debug event
2064 * New BSD user-level threads support
2066 It is now possible to debug programs using the user-level threads
2067 library on OpenBSD and FreeBSD. Currently supported (target)
2070 FreeBSD/amd64 x86_64-*-freebsd*
2071 FreeBSD/i386 i386-*-freebsd*
2072 OpenBSD/i386 i386-*-openbsd*
2074 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2075 are not yet supported.
2077 * New support for Matsushita MN10300 w/sim added
2078 (Work in progress). mn10300-elf.
2080 * REMOVED configurations and files
2082 VxWorks and the XDR protocol *-*-vxworks
2083 Motorola MCORE mcore-*-*
2084 National Semiconductor NS32000 ns32k-*-*
2086 * New "set print array-indexes" command
2088 After turning this setting "on", GDB prints the index of each element
2089 when displaying arrays. The default is "off" to preserve the previous
2092 * VAX floating point support
2094 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2096 * User-defined command support
2098 In addition to using $arg0..$arg9 for argument passing, it is now possible
2099 to use $argc to determine now many arguments have been passed. See the
2100 section on user-defined commands in the user manual for more information.
2102 *** Changes in GDB 6.3:
2104 * New command line option
2106 GDB now accepts -l followed by a number to set the timeout for remote
2109 * GDB works with GCC -feliminate-dwarf2-dups
2111 GDB now supports a more compact representation of DWARF-2 debug
2112 information using DW_FORM_ref_addr references. These are produced
2113 by GCC with the option -feliminate-dwarf2-dups and also by some
2114 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2115 to use -feliminate-dwarf2-dups.
2117 * Internationalization
2119 When supported by the host system, GDB will be built with
2120 internationalization (libintl). The task of marking up the sources is
2121 continued, we're looking forward to our first translation.
2125 Initial support for debugging programs compiled with the GNAT
2126 implementation of the Ada programming language has been integrated
2127 into GDB. In this release, support is limited to expression evaluation.
2129 * New native configurations
2131 GNU/Linux/m32r m32r-*-linux-gnu
2135 GDB's remote protocol now includes support for the 'p' packet. This
2136 packet is used to fetch individual registers from a remote inferior.
2138 * END-OF-LIFE registers[] compatibility module
2140 GDB's internal register infrastructure has been completely rewritten.
2141 The new infrastructure making possible the implementation of key new
2142 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2145 GDB 6.3 will be the last release to include the the registers[]
2146 compatibility module that allowed out-of-date configurations to
2147 continue to work. This change directly impacts the following
2157 powerpc bdm protocol
2159 Unless there is activity to revive these configurations, they will be
2160 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2162 * OBSOLETE configurations and files
2164 Configurations that have been declared obsolete in this release have
2165 been commented out. Unless there is activity to revive these
2166 configurations, the next release of GDB will have their sources
2167 permanently REMOVED.
2176 *** Changes in GDB 6.2.1:
2178 * MIPS `break main; run' gave an heuristic-fence-post warning
2180 When attempting to run even a simple program, a warning about
2181 heuristic-fence-post being hit would be reported. This problem has
2184 * MIPS IRIX 'long double' crashed GDB
2186 When examining a long double variable, GDB would get a segmentation
2187 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2188 IRIX long double values).
2192 A bug in the VAX stack code was causing problems with the "next"
2193 command. This problem has been fixed.
2195 *** Changes in GDB 6.2:
2197 * Fix for ``many threads''
2199 On GNU/Linux systems that use the NPTL threads library, a program
2200 rapidly creating and deleting threads would confuse GDB leading to the
2203 ptrace: No such process.
2204 thread_db_get_info: cannot get thread info: generic error
2206 This problem has been fixed.
2208 * "-async" and "-noasync" options removed.
2210 Support for the broken "-noasync" option has been removed (it caused
2213 * New ``start'' command.
2215 This command runs the program until the begining of the main procedure.
2217 * New BSD Kernel Data Access Library (libkvm) interface
2219 Using ``target kvm'' it is now possible to debug kernel core dumps and
2220 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2221 platforms. Currently supported (native-only) configurations are:
2223 FreeBSD/amd64 x86_64-*-freebsd*
2224 FreeBSD/i386 i?86-*-freebsd*
2225 NetBSD/i386 i?86-*-netbsd*
2226 NetBSD/m68k m68*-*-netbsd*
2227 NetBSD/sparc sparc-*-netbsd*
2228 OpenBSD/amd64 x86_64-*-openbsd*
2229 OpenBSD/i386 i?86-*-openbsd*
2230 OpenBSD/m68k m68*-openbsd*
2231 OpenBSD/sparc sparc-*-openbsd*
2233 * Signal trampoline code overhauled
2235 Many generic problems with GDB's signal handling code have been fixed.
2236 These include: backtraces through non-contiguous stacks; recognition
2237 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2238 call; backtrace through a signal trampoline; step into and out of
2239 signal handlers; and single-stepping in the signal trampoline.
2241 Please note that kernel bugs are a limiting factor here. These
2242 features have been shown to work on an s390 GNU/Linux system that
2243 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2245 * Cygwin support for DWARF 2 added.
2247 * New native configurations
2249 GNU/Linux/hppa hppa*-*-linux*
2250 OpenBSD/hppa hppa*-*-openbsd*
2251 OpenBSD/m68k m68*-*-openbsd*
2252 OpenBSD/m88k m88*-*-openbsd*
2253 OpenBSD/powerpc powerpc-*-openbsd*
2254 NetBSD/vax vax-*-netbsd*
2255 OpenBSD/vax vax-*-openbsd*
2257 * END-OF-LIFE frame compatibility module
2259 GDB's internal frame infrastructure has been completely rewritten.
2260 The new infrastructure making it possible to support key new features
2261 including DWARF 2 Call Frame Information. To aid in the task of
2262 migrating old configurations to this new infrastructure, a
2263 compatibility module, that allowed old configurations to continue to
2264 work, was also included.
2266 GDB 6.2 will be the last release to include this frame compatibility
2267 module. This change directly impacts the following configurations:
2277 Unless there is activity to revive these configurations, they will be
2278 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2280 * REMOVED configurations and files
2282 Sun 3, running SunOS 3 m68*-*-sunos3*
2283 Sun 3, running SunOS 4 m68*-*-sunos4*
2284 Sun 2, running SunOS 3 m68000-*-sunos3*
2285 Sun 2, running SunOS 4 m68000-*-sunos4*
2286 Motorola 680x0 running LynxOS m68*-*-lynxos*
2287 AT&T 3b1/Unix pc m68*-att-*
2288 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2289 decstation mips-dec-* mips-little-*
2290 riscos mips-*-riscos* mips-*-sysv*
2291 sonymips mips-sony-*
2292 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2294 *** Changes in GDB 6.1.1:
2296 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2298 The TUI (Text-mode User Interface) is now built as part of a default
2299 GDB configuration. It is enabled by either selecting the TUI with the
2300 command line option "-i=tui" or by running the separate "gdbtui"
2301 program. For more information on the TUI, see the manual "Debugging
2304 * Pending breakpoint support (also included in GDB 6.1)
2306 Support has been added to allow you to specify breakpoints in shared
2307 libraries that have not yet been loaded. If a breakpoint location
2308 cannot be found, and the "breakpoint pending" option is set to auto,
2309 GDB queries you if you wish to make the breakpoint pending on a future
2310 shared-library load. If and when GDB resolves the breakpoint symbol,
2311 the pending breakpoint is removed as one or more regular breakpoints
2314 Pending breakpoints are very useful for GCJ Java debugging.
2316 * Fixed ISO-C build problems
2318 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2319 non ISO-C code that stopped them being built using a more strict ISO-C
2320 compiler (e.g., IBM's C compiler).
2322 * Fixed build problem on IRIX 5
2324 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2325 wasn't able to compile compile on an IRIX 5 system.
2327 * Added execute permission to gdb/gdbserver/configure
2329 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2330 permission. This bug would cause configure to fail on a number of
2331 systems (Solaris, IRIX). Ref: server/519.
2333 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2335 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2336 has been updated to use constant array sizes.
2338 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2340 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2341 its generated DWARF Call Frame Info. This encoding was causing GDB to
2342 panic, that panic has been fixed. Ref: gdb/1628.
2344 * Fixed a problem when examining parameters in shared library code.
2346 When examining parameters in optimized shared library code generated
2347 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2348 not available''. GDB now correctly displays the variable's value.
2350 *** Changes in GDB 6.1:
2352 * Removed --with-mmalloc
2354 Support for the mmalloc memory manager has been removed, as it
2355 conflicted with the internal gdb byte cache.
2357 * Changes in AMD64 configurations
2359 The AMD64 target now includes the %cs and %ss registers. As a result
2360 the AMD64 remote protocol has changed; this affects the floating-point
2361 and SSE registers. If you rely on those registers for your debugging,
2362 you should upgrade gdbserver on the remote side.
2364 * Revised SPARC target
2366 The SPARC target has been completely revised, incorporating the
2367 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2368 support for LynxOS and SunOS 4 has been dropped. Calling functions
2369 from within GDB on operating systems with a non-executable stack
2370 (Solaris, OpenBSD) now works.
2374 GDB has a new C++ demangler which does a better job on the mangled
2375 names generated by current versions of g++. It also runs faster, so
2376 with this and other changes gdb should now start faster on large C++
2379 * DWARF 2 Location Expressions
2381 GDB support for location expressions has been extended to support function
2382 arguments and frame bases. Older versions of GDB could crash when they
2385 * C++ nested types and namespaces
2387 GDB's support for nested types and namespaces in C++ has been
2388 improved, especially if you use the DWARF 2 debugging format. (This
2389 is the default for recent versions of GCC on most platforms.)
2390 Specifically, if you have a class "Inner" defined within a class or
2391 namespace "Outer", then GDB realizes that the class's name is
2392 "Outer::Inner", not simply "Inner". This should greatly reduce the
2393 frequency of complaints about not finding RTTI symbols. In addition,
2394 if you are stopped at inside of a function defined within a namespace,
2395 GDB modifies its name lookup accordingly.
2397 * New native configurations
2399 NetBSD/amd64 x86_64-*-netbsd*
2400 OpenBSD/amd64 x86_64-*-openbsd*
2401 OpenBSD/alpha alpha*-*-openbsd*
2402 OpenBSD/sparc sparc-*-openbsd*
2403 OpenBSD/sparc64 sparc64-*-openbsd*
2405 * New debugging protocols
2407 M32R with SDI protocol m32r-*-elf*
2409 * "set prompt-escape-char" command deleted.
2411 The command "set prompt-escape-char" has been deleted. This command,
2412 and its very obscure effet on GDB's prompt, was never documented,
2413 tested, nor mentioned in the NEWS file.
2415 * OBSOLETE configurations and files
2417 Configurations that have been declared obsolete in this release have
2418 been commented out. Unless there is activity to revive these
2419 configurations, the next release of GDB will have their sources
2420 permanently REMOVED.
2422 Sun 3, running SunOS 3 m68*-*-sunos3*
2423 Sun 3, running SunOS 4 m68*-*-sunos4*
2424 Sun 2, running SunOS 3 m68000-*-sunos3*
2425 Sun 2, running SunOS 4 m68000-*-sunos4*
2426 Motorola 680x0 running LynxOS m68*-*-lynxos*
2427 AT&T 3b1/Unix pc m68*-att-*
2428 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2429 decstation mips-dec-* mips-little-*
2430 riscos mips-*-riscos* mips-*-sysv*
2431 sonymips mips-sony-*
2432 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2434 * REMOVED configurations and files
2436 SGI Irix-4.x mips-sgi-irix4 or iris4
2437 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2438 Z8000 simulator z8k-zilog-none or z8ksim
2439 Matsushita MN10200 w/simulator mn10200-*-*
2440 H8/500 simulator h8500-hitachi-hms or h8500hms
2441 HP/PA running BSD hppa*-*-bsd*
2442 HP/PA running OSF/1 hppa*-*-osf*
2443 HP/PA Pro target hppa*-*-pro*
2444 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2445 386BSD i[3456]86-*-bsd*
2446 Sequent family i[3456]86-sequent-sysv4*
2447 i[3456]86-sequent-sysv*
2448 i[3456]86-sequent-bsd*
2449 SPARC running LynxOS sparc-*-lynxos*
2450 SPARC running SunOS 4 sparc-*-sunos4*
2451 Tsqware Sparclet sparclet-*-*
2452 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2454 *** Changes in GDB 6.0:
2458 Support for debugging the Objective-C programming language has been
2459 integrated into GDB.
2461 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2463 DWARF 2's Call Frame Information makes available compiler generated
2464 information that more exactly describes the program's run-time stack.
2465 By using this information, GDB is able to provide more robust stack
2468 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2469 have been updated to use a new backtrace mechanism which includes
2470 DWARF 2 CFI support.
2474 GDB's remote protocol has been extended to include support for hosted
2475 file I/O (where the remote target uses GDB's file system). See GDB's
2476 remote protocol documentation for details.
2478 * All targets using the new architecture framework.
2480 All of GDB's targets have been updated to use the new internal
2481 architecture framework. The way is now open for future GDB releases
2482 to include cross-architecture native debugging support (i386 on amd64,
2485 * GNU/Linux's Thread Local Storage (TLS)
2487 GDB now includes support for for the GNU/Linux implementation of
2488 per-thread variables.
2490 * GNU/Linux's Native POSIX Thread Library (NPTL)
2492 GDB's thread code has been updated to work with either the new
2493 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2495 * Separate debug info.
2497 GDB, in conjunction with BINUTILS, now supports a mechanism for
2498 automatically loading debug information from a separate file. Instead
2499 of shipping full debug and non-debug versions of system libraries,
2500 system integrators can now instead ship just the stripped libraries
2501 and optional debug files.
2503 * DWARF 2 Location Expressions
2505 DWARF 2 Location Expressions allow the compiler to more completely
2506 describe the location of variables (even in optimized code) to the
2509 GDB now includes preliminary support for location expressions (support
2510 for DW_OP_piece is still missing).
2514 A number of long standing bugs that caused GDB to die while starting a
2515 Java application have been fixed. GDB's Java support is now
2516 considered "useable".
2518 * GNU/Linux support for fork, vfork, and exec.
2520 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2521 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2524 * GDB supports logging output to a file
2526 There are two new commands, "set logging" and "show logging", which can be
2527 used to capture GDB's output to a file.
2529 * The meaning of "detach" has changed for gdbserver
2531 The "detach" command will now resume the application, as documented. To
2532 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2535 * d10v, m68hc11 `regs' command deprecated
2537 The `info registers' command has been updated so that it displays the
2538 registers using a format identical to the old `regs' command.
2542 A new command, "maint set profile on/off", has been added. This command can
2543 be used to enable or disable profiling while running GDB, to profile a
2544 session or a set of commands. In addition there is a new configure switch,
2545 "--enable-profiling", which will cause GDB to be compiled with profiling
2546 data, for more informative profiling results.
2548 * Default MI syntax changed to "mi2".
2550 The default MI (machine interface) syntax, enabled by the command line
2551 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2552 "mi1", can be enabled by specifying the option "-i=mi1".
2554 Support for the original "mi0" syntax (included in GDB 5.0) has been
2557 Fix for gdb/192: removed extraneous space when displaying frame level.
2558 Fix for gdb/672: update changelist is now output in mi list format.
2559 Fix for gdb/702: a -var-assign that updates the value now shows up
2560 in a subsequent -var-update.
2562 * New native configurations.
2564 FreeBSD/amd64 x86_64-*-freebsd*
2566 * Multi-arched targets.
2568 HP/PA HPUX11 hppa*-*-hpux*
2569 Renesas M32R/D w/simulator m32r-*-elf*
2571 * OBSOLETE configurations and files
2573 Configurations that have been declared obsolete in this release have
2574 been commented out. Unless there is activity to revive these
2575 configurations, the next release of GDB will have their sources
2576 permanently REMOVED.
2578 Z8000 simulator z8k-zilog-none or z8ksim
2579 Matsushita MN10200 w/simulator mn10200-*-*
2580 H8/500 simulator h8500-hitachi-hms or h8500hms
2581 HP/PA running BSD hppa*-*-bsd*
2582 HP/PA running OSF/1 hppa*-*-osf*
2583 HP/PA Pro target hppa*-*-pro*
2584 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2585 Sequent family i[3456]86-sequent-sysv4*
2586 i[3456]86-sequent-sysv*
2587 i[3456]86-sequent-bsd*
2588 Tsqware Sparclet sparclet-*-*
2589 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2591 * REMOVED configurations and files
2594 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2595 IBM AIX PS/2 i[3456]86-*-aix
2596 i386 running Mach 3.0 i[3456]86-*-mach3*
2597 i386 running Mach i[3456]86-*-mach*
2598 i386 running OSF/1 i[3456]86-*osf1mk*
2599 HP/Apollo 68k Family m68*-apollo*-sysv*,
2601 m68*-hp-bsd*, m68*-hp-hpux*
2602 Argonaut Risc Chip (ARC) arc-*-*
2603 Mitsubishi D30V d30v-*-*
2604 Fujitsu FR30 fr30-*-elf*
2605 OS/9000 i[34]86-*-os9k
2606 I960 with MON960 i960-*-coff
2608 * MIPS $fp behavior changed
2610 The convenience variable $fp, for the MIPS, now consistently returns
2611 the address of the current frame's base. Previously, depending on the
2612 context, $fp could refer to either $sp or the current frame's base
2613 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2614 The GNU Source-Level Debugger''.
2616 *** Changes in GDB 5.3:
2618 * GNU/Linux shared library multi-threaded performance improved.
2620 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2621 `/proc', in preference to `ptrace' for memory reads. This may result
2622 in an improvement in the start-up time of multi-threaded, shared
2623 library applications when run under GDB. One GDB user writes: ``loads
2624 shared libs like mad''.
2626 * ``gdbserver'' now supports multi-threaded applications on some targets
2628 Support for debugging multi-threaded applications which use
2629 the GNU/Linux LinuxThreads package has been added for
2630 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2631 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2633 * GDB now supports C/C++ preprocessor macros.
2635 GDB now expands preprocessor macro invocations in C/C++ expressions,
2636 and provides various commands for showing macro definitions and how
2639 The new command `macro expand EXPRESSION' expands any macro
2640 invocations in expression, and shows the result.
2642 The new command `show macro MACRO-NAME' shows the definition of the
2643 macro named MACRO-NAME, and where it was defined.
2645 Most compilers don't include information about macros in the debugging
2646 information by default. In GCC 3.1, for example, you need to compile
2647 your program with the options `-gdwarf-2 -g3'. If the macro
2648 information is present in the executable, GDB will read it.
2650 * Multi-arched targets.
2652 DEC Alpha (partial) alpha*-*-*
2653 DEC VAX (partial) vax-*-*
2655 National Semiconductor NS32000 (partial) ns32k-*-*
2656 Motorola 68000 (partial) m68k-*-*
2657 Motorola MCORE mcore-*-*
2661 Fujitsu FRV architecture added by Red Hat frv*-*-*
2664 * New native configurations
2666 Alpha NetBSD alpha*-*-netbsd*
2667 SH NetBSD sh*-*-netbsdelf*
2668 MIPS NetBSD mips*-*-netbsd*
2669 UltraSPARC NetBSD sparc64-*-netbsd*
2671 * OBSOLETE configurations and files
2673 Configurations that have been declared obsolete in this release have
2674 been commented out. Unless there is activity to revive these
2675 configurations, the next release of GDB will have their sources
2676 permanently REMOVED.
2678 Mitsubishi D30V d30v-*-*
2679 OS/9000 i[34]86-*-os9k
2680 IBM AIX PS/2 i[3456]86-*-aix
2681 Fujitsu FR30 fr30-*-elf*
2682 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2683 Argonaut Risc Chip (ARC) arc-*-*
2684 i386 running Mach 3.0 i[3456]86-*-mach3*
2685 i386 running Mach i[3456]86-*-mach*
2686 i386 running OSF/1 i[3456]86-*osf1mk*
2687 HP/Apollo 68k Family m68*-apollo*-sysv*,
2689 m68*-hp-bsd*, m68*-hp-hpux*
2690 I960 with MON960 i960-*-coff
2692 * OBSOLETE languages
2694 CHILL, a Pascal like language used by telecommunications companies.
2696 * REMOVED configurations and files
2698 AMD 29k family via UDI a29k-amd-udi, udi29k
2699 A29K VxWorks a29k-*-vxworks
2700 AMD 29000 embedded, using EBMON a29k-none-none
2701 AMD 29000 embedded with COFF a29k-none-coff
2702 AMD 29000 embedded with a.out a29k-none-aout
2704 testsuite/gdb.hp/gdb.threads-hp/ directory
2706 * New command "set max-user-call-depth <nnn>"
2708 This command allows the user to limit the call depth of user-defined
2709 commands. The default is 1024.
2711 * Changes in FreeBSD/i386 native debugging.
2713 Support for the "generate-core-file" has been added.
2715 * New commands "dump", "append", and "restore".
2717 These commands allow data to be copied from target memory
2718 to a bfd-format or binary file (dump and append), and back
2719 from a file into memory (restore).
2721 * Improved "next/step" support on multi-processor Alpha Tru64.
2723 The previous single-step mechanism could cause unpredictable problems,
2724 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2725 of a software single-step mechanism prevents this.
2727 *** Changes in GDB 5.2.1:
2735 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2736 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2737 Fix, by Joel Brobecker imported from mainline.
2739 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2740 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2741 Fix, by Fred Fish, imported from mainline.
2743 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2744 Surprisingly enough, it works now.
2745 By Michal Ludvig, imported from mainline.
2747 i386 hardware watchpoint support:
2748 avoid misses on second run for some targets.
2749 By Pierre Muller, imported from mainline.
2751 *** Changes in GDB 5.2:
2753 * New command "set trust-readonly-sections on[off]".
2755 This command is a hint that tells gdb that read-only sections
2756 really are read-only (ie. that their contents will not change).
2757 In this mode, gdb will go to the object file rather than the
2758 target to read memory from read-only sections (such as ".text").
2759 This can be a significant performance improvement on some
2760 (notably embedded) targets.
2762 * New command "generate-core-file" (or "gcore").
2764 This new gdb command allows the user to drop a core file of the child
2765 process state at any time. So far it's been implemented only for
2766 GNU/Linux and Solaris, but should be relatively easily ported to other
2767 hosts. Argument is core file name (defaults to core.<pid>).
2769 * New command line option
2771 GDB now accepts --pid or -p followed by a process id.
2773 * Change in command line behavior -- corefiles vs. process ids.
2775 There is a subtle behavior in the way in which GDB handles
2776 command line arguments. The first non-flag argument is always
2777 a program to debug, but the second non-flag argument may either
2778 be a corefile or a process id. Previously, GDB would attempt to
2779 open the second argument as a corefile, and if that failed, would
2780 issue a superfluous error message and then attempt to attach it as
2781 a process. Now, if the second argument begins with a non-digit,
2782 it will be treated as a corefile. If it begins with a digit,
2783 GDB will attempt to attach it as a process, and if no such process
2784 is found, will then attempt to open it as a corefile.
2786 * Changes in ARM configurations.
2788 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2789 configuration is fully multi-arch.
2791 * New native configurations
2793 ARM NetBSD arm*-*-netbsd*
2794 x86 OpenBSD i[3456]86-*-openbsd*
2795 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2796 Sparc64 running FreeBSD sparc64-*-freebsd*
2800 Sanyo XStormy16 xstormy16-elf
2802 * OBSOLETE configurations and files
2804 Configurations that have been declared obsolete in this release have
2805 been commented out. Unless there is activity to revive these
2806 configurations, the next release of GDB will have their sources
2807 permanently REMOVED.
2809 AMD 29k family via UDI a29k-amd-udi, udi29k
2810 A29K VxWorks a29k-*-vxworks
2811 AMD 29000 embedded, using EBMON a29k-none-none
2812 AMD 29000 embedded with COFF a29k-none-coff
2813 AMD 29000 embedded with a.out a29k-none-aout
2815 testsuite/gdb.hp/gdb.threads-hp/ directory
2817 * REMOVED configurations and files
2819 TI TMS320C80 tic80-*-*
2821 PowerPC Solaris powerpcle-*-solaris*
2822 PowerPC Windows NT powerpcle-*-cygwin32
2823 PowerPC Netware powerpc-*-netware*
2824 Harris/CXUX m88k m88*-harris-cxux*
2825 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2826 ns32k-utek-sysv* ns32k-utek-*
2827 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2828 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2829 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2830 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2831 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2833 * Changes to command line processing
2835 The new `--args' feature can be used to specify command-line arguments
2836 for the inferior from gdb's command line.
2838 * Changes to key bindings
2840 There is a new `operate-and-get-next' function bound to `C-o'.
2842 *** Changes in GDB 5.1.1
2844 Fix compile problem on DJGPP.
2846 Fix a problem with floating-point registers on the i386 being
2849 Fix to stop GDB crashing on .debug_str debug info.
2851 Numerous documentation fixes.
2853 Numerous testsuite fixes.
2855 *** Changes in GDB 5.1:
2857 * New native configurations
2859 Alpha FreeBSD alpha*-*-freebsd*
2860 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2861 MIPS GNU/Linux mips*-*-linux*
2862 MIPS SGI Irix 6.x mips*-sgi-irix6*
2863 ia64 AIX ia64-*-aix*
2864 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2868 Motorola 68HC11 and 68HC12 m68hc11-elf
2870 UltraSparc running GNU/Linux sparc64-*-linux*
2872 * OBSOLETE configurations and files
2874 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2875 Harris/CXUX m88k m88*-harris-cxux*
2876 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2877 ns32k-utek-sysv* ns32k-utek-*
2878 TI TMS320C80 tic80-*-*
2880 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2881 PowerPC Solaris powerpcle-*-solaris*
2882 PowerPC Windows NT powerpcle-*-cygwin32
2883 PowerPC Netware powerpc-*-netware*
2884 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2885 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2886 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2887 Apple Macintosh (MPW) host N/A
2889 stuff.c (Program to stuff files into a specially prepared space in kdb)
2890 kdb-start.c (Main loop for the standalone kernel debugger)
2892 Configurations that have been declared obsolete in this release have
2893 been commented out. Unless there is activity to revive these
2894 configurations, the next release of GDB will have their sources
2895 permanently REMOVED.
2897 * REMOVED configurations and files
2899 Altos 3068 m68*-altos-*
2900 Convex c1-*-*, c2-*-*
2902 ARM RISCix arm-*-* (as host)
2906 * GDB has been converted to ISO C.
2908 GDB's source code has been converted to ISO C. In particular, the
2909 sources are fully protoized, and rely on standard headers being
2914 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2916 * The MI enabled by default.
2918 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2919 revised and enabled by default. Packages which use GDB as a debugging
2920 engine behind a UI or another front end are encouraged to switch to
2921 using the GDB/MI interface, instead of the old annotations interface
2922 which is now deprecated.
2924 * Support for debugging Pascal programs.
2926 GDB now includes support for debugging Pascal programs. The following
2927 main features are supported:
2929 - Pascal-specific data types such as sets;
2931 - automatic recognition of Pascal sources based on file-name
2934 - Pascal-style display of data types, variables, and functions;
2936 - a Pascal expression parser.
2938 However, some important features are not yet supported.
2940 - Pascal string operations are not supported at all;
2942 - there are some problems with boolean types;
2944 - Pascal type hexadecimal constants are not supported
2945 because they conflict with the internal variables format;
2947 - support for Pascal objects and classes is not full yet;
2949 - unlike Pascal, GDB is case-sensitive for symbol names.
2951 * Changes in completion.
2953 Commands such as `shell', `run' and `set args', which pass arguments
2954 to inferior programs, now complete on file names, similar to what
2955 users expect at the shell prompt.
2957 Commands which accept locations, such as `disassemble', `print',
2958 `breakpoint', `until', etc. now complete on filenames as well as
2959 program symbols. Thus, if you type "break foob TAB", and the source
2960 files linked into the programs include `foobar.c', that file name will
2961 be one of the candidates for completion. However, file names are not
2962 considered for completion after you typed a colon that delimits a file
2963 name from a name of a function in that file, as in "break foo.c:bar".
2965 `set demangle-style' completes on available demangling styles.
2967 * New platform-independent commands:
2969 It is now possible to define a post-hook for a command as well as a
2970 hook that runs before the command. For more details, see the
2971 documentation of `hookpost' in the GDB manual.
2973 * Changes in GNU/Linux native debugging.
2975 Support for debugging multi-threaded programs has been completely
2976 revised for all platforms except m68k and sparc. You can now debug as
2977 many threads as your system allows you to have.
2979 Attach/detach is supported for multi-threaded programs.
2981 Support for SSE registers was added for x86. This doesn't work for
2982 multi-threaded programs though.
2984 * Changes in MIPS configurations.
2986 Multi-arch support is enabled for all MIPS configurations.
2988 GDB can now be built as native debugger on SGI Irix 6.x systems for
2989 debugging n32 executables. (Debugging 64-bit executables is not yet
2992 * Unified support for hardware watchpoints in all x86 configurations.
2994 Most (if not all) native x86 configurations support hardware-assisted
2995 breakpoints and watchpoints in a unified manner. This support
2996 implements debug register sharing between watchpoints, which allows to
2997 put a virtually infinite number of watchpoints on the same address,
2998 and also supports watching regions up to 16 bytes with several debug
3001 The new maintenance command `maintenance show-debug-regs' toggles
3002 debugging print-outs in functions that insert, remove, and test
3003 watchpoints and hardware breakpoints.
3005 * Changes in the DJGPP native configuration.
3007 New command ``info dos sysinfo'' displays assorted information about
3008 the CPU, OS, memory, and DPMI server.
3010 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3011 display information about segment descriptors stored in GDT, LDT, and
3014 New commands ``info dos pde'' and ``info dos pte'' display entries
3015 from Page Directory and Page Tables (for now works with CWSDPMI only).
3016 New command ``info dos address-pte'' displays the Page Table entry for
3017 a given linear address.
3019 GDB can now pass command lines longer than 126 characters to the
3020 program being debugged (requires an update to the libdbg.a library
3021 which is part of the DJGPP development kit).
3023 DWARF2 debug info is now supported.
3025 It is now possible to `step' and `next' through calls to `longjmp'.
3027 * Changes in documentation.
3029 All GDB documentation was converted to GFDL, the GNU Free
3030 Documentation License.
3032 Tracepoints-related commands are now fully documented in the GDB
3035 TUI, the Text-mode User Interface, is now documented in the manual.
3037 Tracepoints-related commands are now fully documented in the GDB
3040 The "GDB Internals" manual now has an index. It also includes
3041 documentation of `ui_out' functions, GDB coding standards, x86
3042 hardware watchpoints, and memory region attributes.
3044 * GDB's version number moved to ``version.in''
3046 The Makefile variable VERSION has been replaced by the file
3047 ``version.in''. People creating GDB distributions should update the
3048 contents of this file.
3052 GUD support is now a standard part of the EMACS distribution.
3054 *** Changes in GDB 5.0:
3056 * Improved support for debugging FP programs on x86 targets
3058 Unified and much-improved support for debugging floating-point
3059 programs on all x86 targets. In particular, ``info float'' now
3060 displays the FP registers in the same format on all x86 targets, with
3061 greater level of detail.
3063 * Improvements and bugfixes in hardware-assisted watchpoints
3065 It is now possible to watch array elements, struct members, and
3066 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3067 on x86 targets no longer erroneously trigger when the address is
3070 * Improvements in the native DJGPP version of GDB
3072 The distribution now includes all the scripts and auxiliary files
3073 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3074 machines ``out of the box''.
3076 The DJGPP version can now debug programs that use signals. It is
3077 possible to catch signals that happened in the debuggee, deliver
3078 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3079 would kill the program being debugged.) Programs that hook hardware
3080 interrupts (keyboard, timer, etc.) can also be debugged.
3082 It is now possible to debug DJGPP programs that redirect their
3083 standard handles or switch them to raw (as opposed to cooked) mode, or
3084 even close them. The command ``run < foo > bar'' works as expected,
3085 and ``info terminal'' reports useful information about the debuggee's
3086 terminal, including raw/cooked mode, redirection, etc.
3088 The DJGPP version now uses termios functions for console I/O, which
3089 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3092 DOS-style file names with drive letters are now fully supported by
3095 It is now possible to debug DJGPP programs that switch their working
3096 directory. It is also possible to rerun the debuggee any number of
3097 times without restarting GDB; thus, you can use the same setup,
3098 breakpoints, etc. for many debugging sessions.
3100 * New native configurations
3102 ARM GNU/Linux arm*-*-linux*
3103 PowerPC GNU/Linux powerpc-*-linux*
3107 Motorola MCore mcore-*-*
3108 x86 VxWorks i[3456]86-*-vxworks*
3109 PowerPC VxWorks powerpc-*-vxworks*
3110 TI TMS320C80 tic80-*-*
3112 * OBSOLETE configurations
3114 Altos 3068 m68*-altos-*
3115 Convex c1-*-*, c2-*-*
3117 ARM RISCix arm-*-* (as host)
3120 Configurations that have been declared obsolete will be commented out,
3121 but the code will be left in place. If there is no activity to revive
3122 these configurations before the next release of GDB, the sources will
3123 be permanently REMOVED.
3125 * Gould support removed
3127 Support for the Gould PowerNode and NP1 has been removed.
3129 * New features for SVR4
3131 On SVR4 native platforms (such as Solaris), if you attach to a process
3132 without first loading a symbol file, GDB will now attempt to locate and
3133 load symbols from the running process's executable file.
3135 * Many C++ enhancements
3137 C++ support has been greatly improved. Overload resolution now works properly
3138 in almost all cases. RTTI support is on the way.
3140 * Remote targets can connect to a sub-program
3142 A popen(3) style serial-device has been added. This device starts a
3143 sub-process (such as a stand-alone simulator) and then communicates
3144 with that. The sub-program to run is specified using the syntax
3145 ``|<program> <args>'' vis:
3147 (gdb) set remotedebug 1
3148 (gdb) target extended-remote |mn10300-elf-sim program-args
3150 * MIPS 64 remote protocol
3152 A long standing bug in the mips64 remote protocol where by GDB
3153 expected certain 32 bit registers (ex SR) to be transfered as 32
3154 instead of 64 bits has been fixed.
3156 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3157 added to provide backward compatibility with older versions of GDB.
3159 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3161 The command ``set remotebinarydownload'' command has been replaced by
3162 ``set remote X-packet''. Other commands in ``set remote'' family
3163 include ``set remote P-packet''.
3165 * Breakpoint commands accept ranges.
3167 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3168 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3169 ``tracepoint passcount'' also accepts a range of tracepoints.
3171 * ``apropos'' command added.
3173 The ``apropos'' command searches through command names and
3174 documentation strings, printing out matches, making it much easier to
3175 try to find a command that does what you are looking for.
3179 A new machine oriented interface (MI) has been added to GDB. This
3180 interface is designed for debug environments running GDB as a separate
3181 process. This is part of the long term libGDB project. See the
3182 "GDB/MI" chapter of the GDB manual for further information. It can be
3183 enabled by configuring with:
3185 .../configure --enable-gdbmi
3187 *** Changes in GDB-4.18:
3189 * New native configurations
3191 HP-UX 10.20 hppa*-*-hpux10.20
3192 HP-UX 11.x hppa*-*-hpux11.0*
3193 M68K GNU/Linux m68*-*-linux*
3197 Fujitsu FR30 fr30-*-elf*
3198 Intel StrongARM strongarm-*-*
3199 Mitsubishi D30V d30v-*-*
3201 * OBSOLETE configurations
3203 Gould PowerNode, NP1 np1-*-*, pn-*-*
3205 Configurations that have been declared obsolete will be commented out,
3206 but the code will be left in place. If there is no activity to revive
3207 these configurations before the next release of GDB, the sources will
3208 be permanently REMOVED.
3212 As a compatibility experiment, GDB's source files buildsym.h and
3213 buildsym.c have been converted to pure standard C, no longer
3214 containing any K&R compatibility code. We believe that all systems in
3215 use today either come with a standard C compiler, or have a GCC port
3216 available. If this is not true, please report the affected
3217 configuration to bug-gdb@gnu.org immediately. See the README file for
3218 information about getting a standard C compiler if you don't have one
3223 GDB now uses readline 2.2.
3225 * set extension-language
3227 You can now control the mapping between filename extensions and source
3228 languages by using the `set extension-language' command. For instance,
3229 you can ask GDB to treat .c files as C++ by saying
3230 set extension-language .c c++
3231 The command `info extensions' lists all of the recognized extensions
3232 and their associated languages.
3234 * Setting processor type for PowerPC and RS/6000
3236 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3237 you can use the `set processor' command to specify what variant of the
3238 PowerPC family you are debugging. The command
3242 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3243 following PowerPC and RS6000 variants:
3245 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3246 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3248 403GC IBM PowerPC 403GC
3249 505 Motorola PowerPC 505
3250 860 Motorola PowerPC 860 or 850
3251 601 Motorola PowerPC 601
3252 602 Motorola PowerPC 602
3253 603 Motorola/IBM PowerPC 603 or 603e
3254 604 Motorola PowerPC 604 or 604e
3255 750 Motorola/IBM PowerPC 750 or 750
3257 At the moment, this command just tells GDB what to name the
3258 special-purpose processor registers. Since almost all the affected
3259 registers are inaccessible to user-level programs, this command is
3260 only useful for remote debugging in its present form.
3264 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3265 more extensive support for HP-UX. Added features include shared
3266 library support, kernel threads and hardware watchpoints for 11.00,
3267 support for HP's ANSI C and C++ compilers, and a compatibility mode
3268 for xdb and dbx commands.
3272 HP's donation includes the new concept of catchpoints, which is a
3273 generalization of the old catch command. On HP-UX, it is now possible
3274 to catch exec, fork, and vfork, as well as library loading.
3276 This means that the existing catch command has changed; its first
3277 argument now specifies the type of catch to be set up. See the
3278 output of "help catch" for a list of catchpoint types.
3280 * Debugging across forks
3282 On HP-UX, you can choose which process to debug when a fork() happens
3287 HP has donated a curses-based terminal user interface (TUI). To get
3288 it, build with --enable-tui. Although this can be enabled for any
3289 configuration, at present it only works for native HP debugging.
3291 * GDB remote protocol additions
3293 A new protocol packet 'X' that writes binary data is now available.
3294 Default behavior is to try 'X', then drop back to 'M' if the stub
3295 fails to respond. The settable variable `remotebinarydownload'
3296 allows explicit control over the use of 'X'.
3298 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3299 full 64-bit address. The command
3301 set remoteaddresssize 32
3303 can be used to revert to the old behaviour. For existing remote stubs
3304 the change should not be noticed, as the additional address information
3307 In order to assist in debugging stubs, you may use the maintenance
3308 command `packet' to send any text string to the stub. For instance,
3310 maint packet heythere
3312 sends the packet "$heythere#<checksum>". Note that it is very easy to
3313 disrupt a debugging session by sending the wrong packet at the wrong
3316 The compare-sections command allows you to compare section data on the
3317 target to what is in the executable file without uploading or
3318 downloading, by comparing CRC checksums.
3320 * Tracing can collect general expressions
3322 You may now collect general expressions at tracepoints. This requires
3323 further additions to the target-side stub; see tracepoint.c and
3324 doc/agentexpr.texi for further details.
3326 * mask-address variable for Mips
3328 For Mips targets, you may control the zeroing of the upper 32 bits of
3329 a 64-bit address by entering `set mask-address on'. This is mainly
3330 of interest to users of embedded R4xxx and R5xxx processors.
3332 * Higher serial baud rates
3334 GDB's serial code now allows you to specify baud rates 57600, 115200,
3335 230400, and 460800 baud. (Note that your host system may not be able
3336 to achieve all of these rates.)
3340 The i960 configuration now includes an initial implementation of a
3341 builtin simulator, contributed by Jim Wilson.
3344 *** Changes in GDB-4.17:
3346 * New native configurations
3348 Alpha GNU/Linux alpha*-*-linux*
3349 Unixware 2.x i[3456]86-unixware2*
3350 Irix 6.x mips*-sgi-irix6*
3351 PowerPC GNU/Linux powerpc-*-linux*
3352 PowerPC Solaris powerpcle-*-solaris*
3353 Sparc GNU/Linux sparc-*-linux*
3354 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3358 Argonaut Risc Chip (ARC) arc-*-*
3359 Hitachi H8/300S h8300*-*-*
3360 Matsushita MN10200 w/simulator mn10200-*-*
3361 Matsushita MN10300 w/simulator mn10300-*-*
3362 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3363 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3364 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3365 Mitsubishi D10V w/simulator d10v-*-*
3366 Mitsubishi M32R/D w/simulator m32r-*-elf*
3367 Tsqware Sparclet sparclet-*-*
3368 NEC V850 w/simulator v850-*-*
3370 * New debugging protocols
3372 ARM with RDI protocol arm*-*-*
3373 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3374 DDB and LSI variants of PMON protocol mips*-*-*
3375 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3376 PowerPC with SDS protocol powerpc{,le}-*-eabi
3377 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3381 All configurations can now understand and use the DWARF 2 debugging
3382 format. The choice is automatic, if the symbol file contains DWARF 2
3387 GDB now includes basic Java language support. This support is
3388 only useful with Java compilers that produce native machine code.
3390 * solib-absolute-prefix and solib-search-path
3392 For SunOS and SVR4 shared libraries, you may now set the prefix for
3393 loading absolute shared library symbol files, and the search path for
3394 locating non-absolute shared library symbol files.
3396 * Live range splitting
3398 GDB can now effectively debug code for which GCC has performed live
3399 range splitting as part of its optimization. See gdb/doc/LRS for
3400 more details on the expected format of the stabs information.
3404 GDB's support for the GNU Hurd, including thread debugging, has been
3405 updated to work with current versions of the Hurd.
3409 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3410 instruction set. ARM GDB automatically detects when Thumb
3411 instructions are in use, and adjusts disassembly and backtracing
3416 GDB's MIPS target configurations now handle the MIP16 16-bit
3421 GDB now includes support for overlays; if an executable has been
3422 linked such that multiple sections are based at the same address, GDB
3423 will decide which section to use for symbolic info. You can choose to
3424 control the decision manually, using overlay commands, or implement
3425 additional target-side support and use "overlay load-target" to bring
3426 in the overlay mapping. Do "help overlay" for more detail.
3430 The command "info symbol <address>" displays information about
3431 the symbol at the specified address.
3435 The standard remote protocol now includes an extension that allows
3436 asynchronous collection and display of trace data. This requires
3437 extensive support in the target-side debugging stub. Tracing mode
3438 includes a new interaction mode in GDB and new commands: see the
3439 file tracepoint.c for more details.
3443 Configurations for embedded MIPS now include a simulator contributed
3444 by Cygnus Solutions. The simulator supports the instruction sets
3445 of most MIPS variants.
3449 Sparc configurations may now include the ERC32 simulator contributed
3450 by the European Space Agency. The simulator is not built into
3451 Sparc targets by default; configure with --enable-sim to include it.
3455 For target configurations that may include multiple variants of a
3456 basic architecture (such as MIPS and SH), you may now set the
3457 architecture explicitly. "set arch" sets, "info arch" lists
3458 the possible architectures.
3460 *** Changes in GDB-4.16:
3462 * New native configurations
3464 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3465 M68K NetBSD m68k-*-netbsd*
3466 PowerPC AIX 4.x powerpc-*-aix*
3467 PowerPC MacOS powerpc-*-macos*
3468 PowerPC Windows NT powerpcle-*-cygwin32
3469 RS/6000 AIX 4.x rs6000-*-aix4*
3473 ARM with RDP protocol arm-*-*
3474 I960 with MON960 i960-*-coff
3475 MIPS VxWorks mips*-*-vxworks*
3476 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3477 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3479 Matra Sparclet sparclet-*-*
3483 The powerpc-eabi configuration now includes the PSIM simulator,
3484 contributed by Andrew Cagney, with assistance from Mike Meissner.
3485 PSIM is a very elaborate model of the PowerPC, including not only
3486 basic instruction set execution, but also details of execution unit
3487 performance and I/O hardware. See sim/ppc/README for more details.
3491 GDB now works with Solaris 2.5.
3493 * Windows 95/NT native
3495 GDB will now work as a native debugger on Windows 95 and Windows NT.
3496 To build it from source, you must use the "gnu-win32" environment,
3497 which uses a DLL to emulate enough of Unix to run the GNU tools.
3498 Further information, binaries, and sources are available at
3499 ftp.cygnus.com, under pub/gnu-win32.
3501 * dont-repeat command
3503 If a user-defined command includes the command `dont-repeat', then the
3504 command will not be repeated if the user just types return. This is
3505 useful if the command is time-consuming to run, so that accidental
3506 extra keystrokes don't run the same command many times.
3508 * Send break instead of ^C
3510 The standard remote protocol now includes an option to send a break
3511 rather than a ^C to the target in order to interrupt it. By default,
3512 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3514 * Remote protocol timeout
3516 The standard remote protocol includes a new variable `remotetimeout'
3517 that allows you to set the number of seconds before GDB gives up trying
3518 to read from the target. The default value is 2.
3520 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3522 By default GDB will automatically keep track of objects as they are
3523 loaded and unloaded by the dynamic linker. By using the command `set
3524 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3525 when shared library events occur, thus allowing you to set breakpoints
3526 in shared libraries which are explicitly loaded by the inferior.
3528 Note this feature does not work on hpux8. On hpux9 you must link
3529 /usr/lib/end.o into your program. This feature should work
3530 automatically on hpux10.
3532 * Irix 5.x hardware watchpoint support
3534 Irix 5 configurations now support the use of hardware watchpoints.
3536 * Mips protocol "SYN garbage limit"
3538 When debugging a Mips target using the `target mips' protocol, you
3539 may set the number of characters that GDB will ignore by setting
3540 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3541 every character. The default value is 1050.
3543 * Recording and replaying remote debug sessions
3545 If you set `remotelogfile' to the name of a file, gdb will write to it
3546 a recording of a remote debug session. This recording may then be
3547 replayed back to gdb using "gdbreplay". See gdbserver/README for
3548 details. This is useful when you have a problem with GDB while doing
3549 remote debugging; you can make a recording of the session and send it
3550 to someone else, who can then recreate the problem.
3552 * Speedups for remote debugging
3554 GDB includes speedups for downloading and stepping MIPS systems using
3555 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3556 and more efficient S-record downloading.
3558 * Memory use reductions and statistics collection
3560 GDB now uses less memory and reports statistics about memory usage.
3561 Try the `maint print statistics' command, for example.
3563 *** Changes in GDB-4.15:
3565 * Psymtabs for XCOFF
3567 The symbol reader for AIX GDB now uses partial symbol tables. This
3568 can greatly improve startup time, especially for large executables.
3570 * Remote targets use caching
3572 Remote targets now use a data cache to speed up communication with the
3573 remote side. The data cache could lead to incorrect results because
3574 it doesn't know about volatile variables, thus making it impossible to
3575 debug targets which use memory mapped I/O devices. `set remotecache
3576 off' turns the the data cache off.
3578 * Remote targets may have threads
3580 The standard remote protocol now includes support for multiple threads
3581 in the target system, using new protocol commands 'H' and 'T'. See
3582 gdb/remote.c for details.
3586 If GDB is configured with `--enable-netrom', then it will include
3587 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3588 acts as though it is a bank of ROM on the target board, but you can
3589 write into it over the network. GDB's support consists only of
3590 support for fast loading into the emulated ROM; to debug, you must use
3591 another protocol, such as standard remote protocol. The usual
3592 sequence is something like
3594 target nrom <netrom-hostname>
3596 target remote <netrom-hostname>:1235
3600 GDB now includes support for the Apple Macintosh, as a host only. It
3601 may be run as either an MPW tool or as a standalone application, and
3602 it can debug through the serial port. All the usual GDB commands are
3603 available, but to the target command, you must supply "serial" as the
3604 device type instead of "/dev/ttyXX". See mpw-README in the main
3605 directory for more information on how to build. The MPW configuration
3606 scripts */mpw-config.in support only a few targets, and only the
3607 mips-idt-ecoff target has been tested.
3611 GDB configuration now uses autoconf. This is not user-visible,
3612 but does simplify configuration and building.
3616 GDB now supports hpux10.
3618 *** Changes in GDB-4.14:
3620 * New native configurations
3622 x86 FreeBSD i[345]86-*-freebsd
3623 x86 NetBSD i[345]86-*-netbsd
3624 NS32k NetBSD ns32k-*-netbsd
3625 Sparc NetBSD sparc-*-netbsd
3629 A29K VxWorks a29k-*-vxworks
3630 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3631 CPU32 EST-300 emulator m68*-*-est*
3632 PowerPC ELF powerpc-*-elf
3635 * Alpha OSF/1 support for procfs
3637 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3638 possible to attach to running processes. As the mounting of the /proc
3639 filesystem is optional on the Alpha, GDB automatically determines
3640 the availability of /proc during startup. This can lead to problems
3641 if /proc is unmounted after GDB has been started.
3643 * Arguments to user-defined commands
3645 User commands may accept up to 10 arguments separated by whitespace.
3646 Arguments are accessed within the user command via $arg0..$arg9. A
3649 print $arg0 + $arg1 + $arg2
3651 To execute the command use:
3654 Defines the command "adder" which prints the sum of its three arguments.
3655 Note the arguments are text substitutions, so they may reference variables,
3656 use complex expressions, or even perform inferior function calls.
3658 * New `if' and `while' commands
3660 This makes it possible to write more sophisticated user-defined
3661 commands. Both commands take a single argument, which is the
3662 expression to evaluate, and must be followed by the commands to
3663 execute, one per line, if the expression is nonzero, the list being
3664 terminated by the word `end'. The `if' command list may include an
3665 `else' word, which causes the following commands to be executed only
3666 if the expression is zero.
3668 * Fortran source language mode
3670 GDB now includes partial support for Fortran 77. It will recognize
3671 Fortran programs and can evaluate a subset of Fortran expressions, but
3672 variables and functions may not be handled correctly. GDB will work
3673 with G77, but does not yet know much about symbols emitted by other
3676 * Better HPUX support
3678 Most debugging facilities now work on dynamic executables for HPPAs
3679 running hpux9 or later. You can attach to running dynamically linked
3680 processes, but by default the dynamic libraries will be read-only, so
3681 for instance you won't be able to put breakpoints in them. To change
3682 that behavior do the following before running the program:
3688 This will cause the libraries to be mapped private and read-write.
3689 To revert to the normal behavior, do this:
3695 You cannot set breakpoints or examine data in the library until after
3696 the library is loaded if the function/data symbols do not have
3699 GDB can now also read debug symbols produced by the HP C compiler on
3700 HPPAs (sorry, no C++, Fortran or 68k support).
3702 * Target byte order now dynamically selectable
3704 You can choose which byte order to use with a target system, via the
3705 commands "set endian big" and "set endian little", and you can see the
3706 current setting by using "show endian". You can also give the command
3707 "set endian auto", in which case GDB will use the byte order
3708 associated with the executable. Currently, only embedded MIPS
3709 configurations support dynamic selection of target byte order.
3711 * New DOS host serial code
3713 This version uses DPMI interrupts to handle buffered I/O, so you
3714 no longer need to run asynctsr when debugging boards connected to
3717 *** Changes in GDB-4.13:
3719 * New "complete" command
3721 This lists all the possible completions for the rest of the line, if it
3722 were to be given as a command itself. This is intended for use by emacs.
3724 * Trailing space optional in prompt
3726 "set prompt" no longer adds a space for you after the prompt you set. This
3727 allows you to set a prompt which ends in a space or one that does not.
3729 * Breakpoint hit counts
3731 "info break" now displays a count of the number of times the breakpoint
3732 has been hit. This is especially useful in conjunction with "ignore"; you
3733 can ignore a large number of breakpoint hits, look at the breakpoint info
3734 to see how many times the breakpoint was hit, then run again, ignoring one
3735 less than that number, and this will get you quickly to the last hit of
3738 * Ability to stop printing at NULL character
3740 "set print null-stop" will cause GDB to stop printing the characters of
3741 an array when the first NULL is encountered. This is useful when large
3742 arrays actually contain only short strings.
3744 * Shared library breakpoints
3746 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3747 breakpoints in shared libraries before the executable is run.
3749 * Hardware watchpoints
3751 There is a new hardware breakpoint for the watch command for sparclite
3752 targets. See gdb/sparclite/hw_breakpoint.note.
3754 Hardware watchpoints are also now supported under GNU/Linux.
3758 Annotations have been added. These are for use with graphical interfaces,
3759 and are still experimental. Currently only gdba.el uses these.
3761 * Improved Irix 5 support
3763 GDB now works properly with Irix 5.2.
3765 * Improved HPPA support
3767 GDB now works properly with the latest GCC and GAS.
3769 * New native configurations
3771 Sequent PTX4 i[34]86-sequent-ptx4
3772 HPPA running OSF/1 hppa*-*-osf*
3773 Atari TT running SVR4 m68*-*-sysv4*
3774 RS/6000 LynxOS rs6000-*-lynxos*
3778 OS/9000 i[34]86-*-os9k
3779 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3782 * Hitachi SH7000 and E7000-PC ICE support
3784 There is now support for communicating with the Hitachi E7000-PC ICE.
3785 This is available automatically when GDB is configured for the SH.
3789 As usual, a variety of small fixes and improvements, both generic
3790 and configuration-specific. See the ChangeLog for more detail.
3792 *** Changes in GDB-4.12:
3794 * Irix 5 is now supported
3798 GDB-4.12 on the HPPA has a number of changes which make it unable
3799 to debug the output from the currently released versions of GCC and
3800 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3801 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3802 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3805 *** Changes in GDB-4.11:
3807 * User visible changes:
3811 The "set remotedebug" option is now consistent between the mips remote
3812 target, remote targets using the gdb-specific protocol, UDI (AMD's
3813 debug protocol for the 29k) and the 88k bug monitor. It is now an
3814 integer specifying a debug level (normally 0 or 1, but 2 means more
3815 debugging info for the mips target).
3817 * DEC Alpha native support
3819 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3820 debug info, but GDB works fairly well with the DEC compiler and should
3821 work with a future GCC release. See the README file for a few
3822 Alpha-specific notes.
3824 * Preliminary thread implementation
3826 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3828 * LynxOS native and target support for 386
3830 This release has been hosted on LynxOS 2.2, and also can be configured
3831 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3834 * Improvements in C++ mangling/demangling.
3836 This release has much better g++ debugging, specifically in name
3837 mangling/demangling, virtual function calls, print virtual table,
3838 call methods, ...etc.
3840 *** Changes in GDB-4.10:
3842 * User visible changes:
3844 Remote debugging using the GDB-specific (`target remote') protocol now
3845 supports the `load' command. This is only useful if you have some
3846 other way of getting the stub to the target system, and you can put it
3847 somewhere in memory where it won't get clobbered by the download.
3849 Filename completion now works.
3851 When run under emacs mode, the "info line" command now causes the
3852 arrow to point to the line specified. Also, "info line" prints
3853 addresses in symbolic form (as well as hex).
3855 All vxworks based targets now support a user settable option, called
3856 vxworks-timeout. This option represents the number of seconds gdb
3857 should wait for responses to rpc's. You might want to use this if
3858 your vxworks target is, perhaps, a slow software simulator or happens
3859 to be on the far side of a thin network line.
3863 This release contains support for using a DEC alpha as a GDB host for
3864 cross debugging. Native alpha debugging is not supported yet.
3867 *** Changes in GDB-4.9:
3871 This is the first GDB release which is accompanied by a matching testsuite.
3872 The testsuite requires installation of dejagnu, which should be available
3873 via ftp from most sites that carry GNU software.
3877 'Cfront' style demangling has had its name changed to 'ARM' style, to
3878 emphasize that it was written from the specifications in the C++ Annotated
3879 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3880 disclaimers, it still generated too much confusion with users attempting to
3881 use gdb with AT&T cfront.
3885 GDB now uses a standard remote interface to a simulator library.
3886 So far, the library contains simulators for the Zilog Z8001/2, the
3887 Hitachi H8/300, H8/500 and Super-H.
3889 * New targets supported
3891 H8/300 simulator h8300-hitachi-hms or h8300hms
3892 H8/500 simulator h8500-hitachi-hms or h8500hms
3893 SH simulator sh-hitachi-hms or sh
3894 Z8000 simulator z8k-zilog-none or z8ksim
3895 IDT MIPS board over serial line mips-idt-ecoff
3897 Cross-debugging to GO32 targets is supported. It requires a custom
3898 version of the i386-stub.c module which is integrated with the
3899 GO32 memory extender.
3901 * New remote protocols
3903 MIPS remote debugging protocol.
3905 * New source languages supported
3907 This version includes preliminary support for Chill, a Pascal like language
3908 used by telecommunications companies. Chill support is also being integrated
3909 into the GNU compiler, but we don't know when it will be publically available.
3912 *** Changes in GDB-4.8:
3914 * HP Precision Architecture supported
3916 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3917 version of this support was available as a set of patches from the
3918 University of Utah. GDB does not support debugging of programs
3919 compiled with the HP compiler, because HP will not document their file
3920 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3921 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3923 Many problems in the preliminary version have been fixed.
3925 * Faster and better demangling
3927 We have improved template demangling and fixed numerous bugs in the GNU style
3928 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3929 character types (wchar_t) are now supported. Demangling of each symbol is now
3930 only done once, and is cached when the symbol table for a file is read in.
3931 This results in a small increase in memory usage for C programs, a moderate
3932 increase in memory usage for C++ programs, and a fantastic speedup in
3935 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3936 from the specifications in the Annotated Reference Manual, which AT&T's
3937 compiler does not actually implement.
3939 * G++ multiple inheritance compiler problem
3941 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3942 inheritance lattices was reworked to properly discover ambiguities. We
3943 recently found an example which causes this new algorithm to fail in a
3944 very subtle way, producing bad debug information for those classes.
3945 The file 'gcc.patch' (in this directory) can be applied to gcc to
3946 circumvent the problem. A future GCC release will contain a complete
3949 The previous G++ debug info problem (mentioned below for the gdb-4.7
3950 release) is fixed in gcc version 2.3.2.
3952 * Improved configure script
3954 The `configure' script will now attempt to guess your system type if
3955 you don't supply a host system type. The old scheme of supplying a
3956 host system triplet is preferable over using this. All the magic is
3957 done in the new `config.guess' script. Examine it for details.
3959 We have also brought our configure script much more in line with the FSF's
3960 version. It now supports the --with-xxx options. In particular,
3961 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3962 The resulting GDB will not be able to read arbitrary object file formats --
3963 only the format ``expected'' to be used on the configured target system.
3964 We hope to make this the default in a future release.
3966 * Documentation improvements
3968 There's new internal documentation on how to modify GDB, and how to
3969 produce clean changes to the code. We implore people to read it
3970 before submitting changes.
3972 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3973 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3974 `info' files are also provided. To build `info' files from scratch,
3975 you will need the latest `makeinfo' release, which will be available in
3976 a future texinfo-X.Y release.
3978 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3979 We're not sure exactly which versions have this problem, but it has
3980 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3981 or better. If that isn't possible, there is a patch in
3982 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3983 around this problem.
3987 GDB now supports array constants that can be used in expressions typed in by
3988 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3989 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3992 The new directory `gdb/sparclite' contains a program that demonstrates
3993 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3995 * New native hosts supported
3997 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3998 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4000 * New targets supported
4002 AMD 29k family via UDI a29k-amd-udi or udi29k
4004 * New file formats supported
4006 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4007 HPUX core files, and SCO 3.2v2 core files.
4011 Attaching to processes now works again; thanks for the many bug reports.
4013 We have also stomped on a bunch of core dumps caused by
4014 printf_filtered("%s") problems.
4016 We eliminated a copyright problem on the rpc and ptrace header files
4017 for VxWorks, which was discovered at the last minute during the 4.7
4018 release. You should now be able to build a VxWorks GDB.
4020 You can now interrupt gdb while an attached process is running. This
4021 will cause the attached process to stop, and give control back to GDB.
4023 We fixed problems caused by using too many file descriptors
4024 for reading symbols from object files and libraries. This was
4025 especially a problem for programs that used many (~100) shared
4028 The `step' command now only enters a subroutine if there is line number
4029 information for the subroutine. Otherwise it acts like the `next'
4030 command. Previously, `step' would enter subroutines if there was
4031 any debugging information about the routine. This avoids problems
4032 when using `cc -g1' on MIPS machines.
4034 * Internal improvements
4036 GDB's internal interfaces have been improved to make it easier to support
4037 debugging of multiple languages in the future.
4039 GDB now uses a common structure for symbol information internally.
4040 Minimal symbols (derived from linkage symbols in object files), partial
4041 symbols (from a quick scan of debug information), and full symbols
4042 contain a common subset of information, making it easier to write
4043 shared code that handles any of them.
4045 * New command line options
4047 We now accept --silent as an alias for --quiet.
4051 The memory-mapped-malloc library is now licensed under the GNU Library
4052 General Public License.
4054 *** Changes in GDB-4.7:
4056 * Host/native/target split
4058 GDB has had some major internal surgery to untangle the support for
4059 hosts and remote targets. Now, when you configure GDB for a remote
4060 target, it will no longer load in all of the support for debugging
4061 local programs on the host. When fully completed and tested, this will
4062 ensure that arbitrary host/target combinations are possible.
4064 The primary conceptual shift is to separate the non-portable code in
4065 GDB into three categories. Host specific code is required any time GDB
4066 is compiled on that host, regardless of the target. Target specific
4067 code relates to the peculiarities of the target, but can be compiled on
4068 any host. Native specific code is everything else: it can only be
4069 built when the host and target are the same system. Child process
4070 handling and core file support are two common `native' examples.
4072 GDB's use of /proc for controlling Unix child processes is now cleaner.
4073 It has been split out into a single module under the `target_ops' vector,
4074 plus two native-dependent functions for each system that uses /proc.
4076 * New hosts supported
4078 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4079 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4080 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4082 * New targets supported
4084 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4085 68030 and CPU32 m68030-*-*, m68332-*-*
4087 * New native hosts supported
4089 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4090 (386bsd is not well tested yet)
4091 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4093 * New file formats supported
4095 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4096 supports reading of `a.out.adobe' object files, which are an a.out
4097 format extended with minimal information about multiple sections.
4101 `show copying' is the same as the old `info copying'.
4102 `show warranty' is the same as `info warrantee'.
4103 These were renamed for consistency. The old commands continue to work.
4105 `info handle' is a new alias for `info signals'.
4107 You can now define pre-command hooks, which attach arbitrary command
4108 scripts to any command. The commands in the hook will be executed
4109 prior to the user's command. You can also create a hook which will be
4110 executed whenever the program stops. See gdb.texinfo.
4114 We now deal with Cfront style name mangling, and can even extract type
4115 info from mangled symbols. GDB can automatically figure out which
4116 symbol mangling style your C++ compiler uses.
4118 Calling of methods and virtual functions has been improved as well.
4122 The crash that occured when debugging Sun Ansi-C compiled binaries is
4123 fixed. This was due to mishandling of the extra N_SO stabs output
4126 We also finally got Ultrix 4.2 running in house, and fixed core file
4127 support, with help from a dozen people on the net.
4129 John M. Farrell discovered that the reason that single-stepping was so
4130 slow on all of the Mips based platforms (primarily SGI and DEC) was
4131 that we were trying to demangle and lookup a symbol used for internal
4132 purposes on every instruction that was being stepped through. Changing
4133 the name of that symbol so that it couldn't be mistaken for a C++
4134 mangled symbol sped things up a great deal.
4136 Rich Pixley sped up symbol lookups in general by getting much smarter
4137 about when C++ symbol mangling is necessary. This should make symbol
4138 completion (TAB on the command line) much faster. It's not as fast as
4139 we'd like, but it's significantly faster than gdb-4.6.
4143 A new user controllable variable 'call_scratch_address' can
4144 specify the location of a scratch area to be used when GDB
4145 calls a function in the target. This is necessary because the
4146 usual method of putting the scratch area on the stack does not work
4147 in systems that have separate instruction and data spaces.
4149 We integrated changes to support the 29k UDI (Universal Debugger
4150 Interface), but discovered at the last minute that we didn't have all
4151 of the appropriate copyright paperwork. We are working with AMD to
4152 resolve this, and hope to have it available soon.
4156 We have sped up the remote serial line protocol, especially for targets
4157 with lots of registers. It now supports a new `expedited status' ('T')
4158 message which can be used in place of the existing 'S' status message.
4159 This allows the remote stub to send only the registers that GDB
4160 needs to make a quick decision about single-stepping or conditional
4161 breakpoints, eliminating the need to fetch the entire register set for
4162 each instruction being stepped through.
4164 The GDB remote serial protocol now implements a write-through cache for
4165 registers, only re-reading the registers if the target has run.
4167 There is also a new remote serial stub for SPARC processors. You can
4168 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4169 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4170 processor with a serial port.
4174 Configure.in files have become much easier to read and modify. A new
4175 `table driven' format makes it more obvious what configurations are
4176 supported, and what files each one uses.
4180 There is a new opcodes library which will eventually contain all of the
4181 disassembly routines and opcode tables. At present, it only contains
4182 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4183 disassembler (binutils/objdump) to share these routines.
4185 The libiberty library is now copylefted under the GNU Library General
4186 Public License. This allows more liberal use, and was done so libg++
4187 can use it. This makes no difference to GDB, since the Library License
4188 grants all the rights from the General Public License.
4192 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4193 reference to the stabs symbol info used by the debugger. It is (as far
4194 as we know) the only published document on this fascinating topic. We
4195 encourage you to read it, compare it to the stabs information on your
4196 system, and send improvements on the document in general (to
4197 bug-gdb@prep.ai.mit.edu).
4199 And, of course, many bugs have been fixed.
4202 *** Changes in GDB-4.6:
4204 * Better support for C++ function names
4206 GDB now accepts as input the "demangled form" of C++ overloaded function
4207 names and member function names, and can do command completion on such names
4208 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4209 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4210 Make use of command completion, it is your friend.
4212 GDB also now accepts a variety of C++ mangled symbol formats. They are
4213 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4214 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4215 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4216 for the list of formats.
4218 * G++ symbol mangling problem
4220 Recent versions of gcc have a bug in how they emit debugging information for
4221 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4222 directory) can be applied to gcc to fix the problem. Alternatively, if you
4223 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4224 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4225 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4228 * New 'maintenance' command
4230 All of the commands related to hacking GDB internals have been moved out of
4231 the main command set, and now live behind the 'maintenance' command. This
4232 can also be abbreviated as 'mt'. The following changes were made:
4234 dump-me -> maintenance dump-me
4235 info all-breakpoints -> maintenance info breakpoints
4236 printmsyms -> maintenance print msyms
4237 printobjfiles -> maintenance print objfiles
4238 printpsyms -> maintenance print psymbols
4239 printsyms -> maintenance print symbols
4241 The following commands are new:
4243 maintenance demangle Call internal GDB demangler routine to
4244 demangle a C++ link name and prints the result.
4245 maintenance print type Print a type chain for a given symbol
4247 * Change to .gdbinit file processing
4249 We now read the $HOME/.gdbinit file before processing the argv arguments
4250 (e.g. reading symbol files or core files). This allows global parameters to
4251 be set, which will apply during the symbol reading. The ./.gdbinit is still
4252 read after argv processing.
4254 * New hosts supported
4256 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4258 GNU/Linux support i386-unknown-linux or linux
4260 We are also including code to support the HP/PA running BSD and HPUX. This
4261 is almost guaranteed not to work, as we didn't have time to test or build it
4262 for this release. We are including it so that the more adventurous (or
4263 masochistic) of you can play with it. We also had major problems with the
4264 fact that the compiler that we got from HP doesn't support the -g option.
4267 * New targets supported
4269 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4271 * More smarts about finding #include files
4273 GDB now remembers the compilation directory for all include files, and for
4274 all files from which C is generated (like yacc and lex sources). This
4275 greatly improves GDB's ability to find yacc/lex sources, and include files,
4276 especially if you are debugging your program from a directory different from
4277 the one that contains your sources.
4279 We also fixed a bug which caused difficulty with listing and setting
4280 breakpoints in include files which contain C code. (In the past, you had to
4281 try twice in order to list an include file that you hadn't looked at before.)
4283 * Interesting infernals change
4285 GDB now deals with arbitrary numbers of sections, where the symbols for each
4286 section must be relocated relative to that section's landing place in the
4287 target's address space. This work was needed to support ELF with embedded
4288 stabs used by Solaris-2.0.
4290 * Bug fixes (of course!)
4292 There have been loads of fixes for the following things:
4293 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4294 i960, stabs, DOS(GO32), procfs, etc...
4296 See the ChangeLog for details.
4298 *** Changes in GDB-4.5:
4300 * New machines supported (host and target)
4302 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4304 SGI Irix-4.x mips-sgi-irix4 or iris4
4306 * New malloc package
4308 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4309 Mmalloc is capable of handling mutiple heaps of memory. It is also
4310 capable of saving a heap to a file, and then mapping it back in later.
4311 This can be used to greatly speedup the startup of GDB by using a
4312 pre-parsed symbol table which lives in a mmalloc managed heap. For
4313 more details, please read mmalloc/mmalloc.texi.
4317 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4318 'help info proc' for details.
4320 * MIPS ecoff symbol table format
4322 The code that reads MIPS symbol table format is now supported on all hosts.
4323 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4326 * File name changes for MS-DOS
4328 Many files in the config directories have been renamed to make it easier to
4329 support GDB on MS-DOSe systems (which have very restrictive file name
4330 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4331 environment) is close to working but has some remaining problems. Note
4332 that debugging of DOS programs is not supported, due to limitations
4333 in the ``operating system'', but it can be used to host cross-debugging.
4335 * Cross byte order fixes
4337 Many fixes have been made to support cross debugging of Sparc and MIPS
4338 targets from hosts whose byte order differs.
4340 * New -mapped and -readnow options
4342 If memory-mapped files are available on your system through the 'mmap'
4343 system call, you can use the -mapped option on the `file' or
4344 `symbol-file' commands to cause GDB to write the symbols from your
4345 program into a reusable file. If the program you are debugging is
4346 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4347 Future GDB debugging sessions will notice the presence of this file,
4348 and will quickly map in symbol information from it, rather than reading
4349 the symbol table from the executable program. Using the '-mapped'
4350 option in a GDB `file' or `symbol-file' command has the same effect as
4351 starting GDB with the '-mapped' command-line option.
4353 You can cause GDB to read the entire symbol table immediately by using
4354 the '-readnow' option with any of the commands that load symbol table
4355 information (or on the GDB command line). This makes the command
4356 slower, but makes future operations faster.
4358 The -mapped and -readnow options are typically combined in order to
4359 build a `fred.syms' file that contains complete symbol information.
4360 A simple GDB invocation to do nothing but build a `.syms' file for future
4363 gdb -batch -nx -mapped -readnow programname
4365 The `.syms' file is specific to the host machine on which GDB is run.
4366 It holds an exact image of GDB's internal symbol table. It cannot be
4367 shared across multiple host platforms.
4369 * longjmp() handling
4371 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4372 siglongjmp() without losing control. This feature has not yet been ported to
4373 all systems. It currently works on many 386 platforms, all MIPS-based
4374 platforms (SGI, DECstation, etc), and Sun3/4.
4378 Preliminary work has been put in to support the new Solaris OS from Sun. At
4379 this time, it can control and debug processes, but it is not capable of
4384 As always, many many bug fixes. The major areas were with g++, and mipsread.
4385 People using the MIPS-based platforms should experience fewer mysterious
4386 crashes and trashed symbol tables.
4388 *** Changes in GDB-4.4:
4390 * New machines supported (host and target)
4392 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4394 BSD Reno on Vax vax-dec-bsd
4395 Ultrix on Vax vax-dec-ultrix
4397 * New machines supported (target)
4399 AMD 29000 embedded, using EBMON a29k-none-none
4403 GDB continues to improve its handling of C++. `References' work better.
4404 The demangler has also been improved, and now deals with symbols mangled as
4405 per the Annotated C++ Reference Guide.
4407 GDB also now handles `stabs' symbol information embedded in MIPS
4408 `ecoff' symbol tables. Since the ecoff format was not easily
4409 extensible to handle new languages such as C++, this appeared to be a
4410 good way to put C++ debugging info into MIPS binaries. This option
4411 will be supported in the GNU C compiler, version 2, when it is
4414 * New features for SVR4
4416 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4417 shared libraries. Debugging dynamically linked programs should present
4418 only minor differences from debugging statically linked programs.
4420 The `info proc' command will print out information about any process
4421 on an SVR4 system (including the one you are debugging). At the moment,
4422 it prints the address mappings of the process.
4424 If you bring up GDB on another SVR4 system, please send mail to
4425 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4427 * Better dynamic linking support in SunOS
4429 Reading symbols from shared libraries which contain debugging symbols
4430 now works properly. However, there remain issues such as automatic
4431 skipping of `transfer vector' code during function calls, which
4432 make it harder to debug code in a shared library, than to debug the
4433 same code linked statically.
4437 GDB is now using the latest `getopt' routines from the FSF. This
4438 version accepts the -- prefix for options with long names. GDB will
4439 continue to accept the old forms (-option and +option) as well.
4440 Various single letter abbreviations for options have been explicity
4441 added to the option table so that they won't get overshadowed in the
4442 future by other options that begin with the same letter.
4446 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4447 Many assorted bugs have been handled. Many more remain to be handled.
4448 See the various ChangeLog files (primarily in gdb and bfd) for details.
4451 *** Changes in GDB-4.3:
4453 * New machines supported (host and target)
4455 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4456 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4457 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4459 * Almost SCO Unix support
4461 We had hoped to support:
4462 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4463 (except for core file support), but we discovered very late in the release
4464 that it has problems with process groups that render gdb unusable. Sorry
4465 about that. I encourage people to fix it and post the fixes.
4467 * Preliminary ELF and DWARF support
4469 GDB can read ELF object files on System V Release 4, and can handle
4470 debugging records for C, in DWARF format, in ELF files. This support
4471 is preliminary. If you bring up GDB on another SVR4 system, please
4472 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4477 GDB now uses the latest `readline' library. One user-visible change
4478 is that two tabs will list possible command completions, which previously
4479 required typing M-? (meta-question mark, or ESC ?).
4483 The `stepi' bug that many of you noticed has been squashed.
4484 Many bugs in C++ have been handled. Many more remain to be handled.
4485 See the various ChangeLog files (primarily in gdb and bfd) for details.
4487 * State of the MIPS world (in case you wondered):
4489 GDB can understand the symbol tables emitted by the compilers
4490 supplied by most vendors of MIPS-based machines, including DEC. These
4491 symbol tables are in a format that essentially nobody else uses.
4493 Some versions of gcc come with an assembler post-processor called
4494 mips-tfile. This program is required if you want to do source-level
4495 debugging of gcc-compiled programs. I believe FSF does not ship
4496 mips-tfile with gcc version 1, but it will eventually come with gcc
4499 Debugging of g++ output remains a problem. g++ version 1.xx does not
4500 really support it at all. (If you're lucky, you should be able to get
4501 line numbers and stack traces to work, but no parameters or local
4502 variables.) With some work it should be possible to improve the
4505 When gcc version 2 is released, you will have somewhat better luck.
4506 However, even then you will get confusing results for inheritance and
4509 We will eventually provide full debugging of g++ output on
4510 DECstations. This will probably involve some kind of stabs-in-ecoff
4511 encapulation, but the details have not been worked out yet.
4514 *** Changes in GDB-4.2:
4516 * Improved configuration
4518 Only one copy of `configure' exists now, and it is not self-modifying.
4519 Porting BFD is simpler.
4523 The `step' and `next' commands now only stop at the first instruction
4524 of a source line. This prevents the multiple stops that used to occur
4525 in switch statements, for-loops, etc. `Step' continues to stop if a
4526 function that has debugging information is called within the line.
4530 Lots of small bugs fixed. More remain.
4532 * New host supported (not target)
4534 Intel 386 PC clone running Mach i386-none-mach
4537 *** Changes in GDB-4.1:
4539 * Multiple source language support
4541 GDB now has internal scaffolding to handle several source languages.
4542 It determines the type of each source file from its filename extension,
4543 and will switch expression parsing and number formatting to match the
4544 language of the function in the currently selected stack frame.
4545 You can also specifically set the language to be used, with
4546 `set language c' or `set language modula-2'.
4550 GDB now has preliminary support for the GNU Modula-2 compiler,
4551 currently under development at the State University of New York at
4552 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4553 continue through the fall of 1991 and into 1992.
4555 Other Modula-2 compilers are currently not supported, and attempting to
4556 debug programs compiled with them will likely result in an error as the
4557 symbol table is read. Feel free to work on it, though!
4559 There are hooks in GDB for strict type checking and range checking,
4560 in the `Modula-2 philosophy', but they do not currently work.
4564 GDB can now write to executable and core files (e.g. patch
4565 a variable's value). You must turn this switch on, specify
4566 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4567 by assigning a new value to a variable. Modifications take
4570 * Automatic SunOS shared library reading
4572 When you run your program, GDB automatically determines where its
4573 shared libraries (if any) have been loaded, and reads their symbols.
4574 The `share' command is no longer needed. This also works when
4575 examining core files.
4579 You can specify the number of lines that the `list' command shows.
4582 * New machines supported (host and target)
4584 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4585 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4586 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4588 * New hosts supported (not targets)
4590 IBM RT/PC: romp-ibm-aix or rtpc
4592 * New targets supported (not hosts)
4594 AMD 29000 embedded with COFF a29k-none-coff
4595 AMD 29000 embedded with a.out a29k-none-aout
4596 Ultracomputer remote kernel debug a29k-nyu-kern
4598 * New remote interfaces
4604 *** Changes in GDB-4.0:
4608 Wide output is wrapped at good places to make the output more readable.
4610 Gdb now supports cross-debugging from a host machine of one type to a
4611 target machine of another type. Communication with the target system
4612 is over serial lines. The ``target'' command handles connecting to the
4613 remote system; the ``load'' command will download a program into the
4614 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4615 also supports debugging of realtime processes running under VxWorks,
4616 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4617 stub on the target system.
4619 New CPUs supported include the AMD 29000 and Intel 960.
4621 GDB now reads object files and symbol tables via a ``binary file''
4622 library, which allows a single copy of GDB to debug programs of multiple
4623 object file types such as a.out and coff.
4625 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4626 refcard.dvi and refcard.ps are available to format it).
4629 * Control-Variable user interface simplified
4631 All variables that control the operation of the debugger can be set
4632 by the ``set'' command, and displayed by the ``show'' command.
4634 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4635 ``Show prompt'' produces the response:
4636 Gdb's prompt is new-gdb=>.
4638 What follows are the NEW set commands. The command ``help set'' will
4639 print a complete list of old and new set commands. ``help set FOO''
4640 will give a longer description of the variable FOO. ``show'' will show
4641 all of the variable descriptions and their current settings.
4643 confirm on/off: Enables warning questions for operations that are
4644 hard to recover from, e.g. rerunning the program while
4645 it is already running. Default is ON.
4647 editing on/off: Enables EMACS style command line editing
4648 of input. Previous lines can be recalled with
4649 control-P, the current line can be edited with control-B,
4650 you can search for commands with control-R, etc.
4653 history filename NAME: NAME is where the gdb command history
4654 will be stored. The default is .gdb_history,
4655 or the value of the environment variable
4658 history size N: The size, in commands, of the command history. The
4659 default is 256, or the value of the environment variable
4662 history save on/off: If this value is set to ON, the history file will
4663 be saved after exiting gdb. If set to OFF, the
4664 file will not be saved. The default is OFF.
4666 history expansion on/off: If this value is set to ON, then csh-like
4667 history expansion will be performed on
4668 command line input. The default is OFF.
4670 radix N: Sets the default radix for input and output. It can be set
4671 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4672 in the current radix, so "set radix 10" is always a no-op.
4674 height N: This integer value is the number of lines on a page. Default
4675 is 24, the current `stty rows'' setting, or the ``li#''
4676 setting from the termcap entry matching the environment
4679 width N: This integer value is the number of characters on a line.
4680 Default is 80, the current `stty cols'' setting, or the ``co#''
4681 setting from the termcap entry matching the environment
4684 Note: ``set screensize'' is obsolete. Use ``set height'' and
4685 ``set width'' instead.
4687 print address on/off: Print memory addresses in various command displays,
4688 such as stack traces and structure values. Gdb looks
4689 more ``symbolic'' if you turn this off; it looks more
4690 ``machine level'' with it on. Default is ON.
4692 print array on/off: Prettyprint arrays. New convenient format! Default
4695 print demangle on/off: Print C++ symbols in "source" form if on,
4698 print asm-demangle on/off: Same, for assembler level printouts
4701 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4704 * Support for Epoch Environment.
4706 The epoch environment is a version of Emacs v18 with windowing. One
4707 new command, ``inspect'', is identical to ``print'', except that if you
4708 are running in the epoch environment, the value is printed in its own
4712 * Support for Shared Libraries
4714 GDB can now debug programs and core files that use SunOS shared libraries.
4715 Symbols from a shared library cannot be referenced
4716 before the shared library has been linked with the program (this
4717 happens after you type ``run'' and before the function main() is entered).
4718 At any time after this linking (including when examining core files
4719 from dynamically linked programs), gdb reads the symbols from each
4720 shared library when you type the ``sharedlibrary'' command.
4721 It can be abbreviated ``share''.
4723 sharedlibrary REGEXP: Load shared object library symbols for files
4724 matching a unix regular expression. No argument
4725 indicates to load symbols for all shared libraries.
4727 info sharedlibrary: Status of loaded shared libraries.
4732 A watchpoint stops execution of a program whenever the value of an
4733 expression changes. Checking for this slows down execution
4734 tremendously whenever you are in the scope of the expression, but is
4735 quite useful for catching tough ``bit-spreader'' or pointer misuse
4736 problems. Some machines such as the 386 have hardware for doing this
4737 more quickly, and future versions of gdb will use this hardware.
4739 watch EXP: Set a watchpoint (breakpoint) for an expression.
4741 info watchpoints: Information about your watchpoints.
4743 delete N: Deletes watchpoint number N (same as breakpoints).
4744 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4745 enable N: Re-enables watchpoint number N (same as breakpoints).
4748 * C++ multiple inheritance
4750 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4753 * C++ exception handling
4755 Gdb now supports limited C++ exception handling. Besides the existing
4756 ability to breakpoint on an exception handler, gdb can breakpoint on
4757 the raising of an exception (before the stack is peeled back to the
4760 catch FOO: If there is a FOO exception handler in the dynamic scope,
4761 set a breakpoint to catch exceptions which may be raised there.
4762 Multiple exceptions (``catch foo bar baz'') may be caught.
4764 info catch: Lists all exceptions which may be caught in the
4765 current stack frame.
4768 * Minor command changes
4770 The command ``call func (arg, arg, ...)'' now acts like the print
4771 command, except it does not print or save a value if the function's result
4772 is void. This is similar to dbx usage.
4774 The ``up'' and ``down'' commands now always print the frame they end up
4775 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4776 frames without printing.
4778 * New directory command
4780 'dir' now adds directories to the FRONT of the source search path.
4781 The path starts off empty. Source files that contain debug information
4782 about the directory in which they were compiled can be found even
4783 with an empty path; Sun CC and GCC include this information. If GDB can't
4784 find your source file in the current directory, type "dir .".
4786 * Configuring GDB for compilation
4788 For normal use, type ``./configure host''. See README or gdb.texinfo
4791 GDB now handles cross debugging. If you are remotely debugging between
4792 two different machines, type ``./configure host -target=targ''.
4793 Host is the machine where GDB will run; targ is the machine
4794 where the program that you are debugging will run.