1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.3.1
6 * GDB now allows you to skip uninteresting functions and files when
7 stepping with the "skip function" and "skip file" commands.
9 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
10 and "show remote hardware-watchpoint-length-limit". These allows to
11 set or show the maximum length limit (in bytes) of a remote
12 target hardware watchpoint.
14 This allows e.g. to use "unlimited" hardware watchpoints with the
15 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
16 watchpoints are slower than real hardware watchpoints but are
17 significantly faster than gdb software watchpoints.
21 ** The register_pretty_printer function in module gdb.printing now takes
22 an optional `replace' argument. If True, the new printer replaces any
25 ** The "maint set python print-stack on|off" command has been
26 deprecated, and a new command: "set python print-stack on|off" has
27 replaced it. Additionally, the default for "print-stack" is now
30 ** A prompt substitution hook (prompt_hook) is now available to the
33 ** A new Python module, gdb.prompt has been added to the GDB Python
34 modules library. This module provides functionality for
35 escape sequences in prompts (used by set/show
36 extended-prompt). These escape sequences are replaced by their
39 ** Python commands and convenience-functions located in
40 'data-directory'/python/gdb/command and
41 'data-directory'/python/gdb/function are now automatically loaded
44 ** Blocks now provide four new attributes. global_block and
45 static_block will return the global and static blocks
46 respectively. is_static and is_global are boolean attributes
47 that indicate if the block is one of those two types.
49 ** Symbols now provide the "type" attribute, the type of the symbol.
51 ** The "gdb.breakpoint" function has been deprecated in favor of
54 ** Type objects for struct and union types now allow access to
55 the fields using standard Python dictionary (mapping) methods.
56 For example, "some_type['myfield']" now works, as does
59 ** A new event "gdb.new_objfile" has been added, triggered by loading a
62 ** A new function, "deep_items" has been added to the gdb.types
63 module in the GDB Python modules library. This function returns
64 an iterator over the fields of a struct or union type. Unlike
65 the standard Python "iteritems" method, it will recursively traverse
68 * libthread-db-search-path now supports two special values: $sdir and $pdir.
69 $sdir specifies the default system locations of shared libraries.
70 $pdir specifies the directory where the libpthread used by the application
73 GDB no longer looks in $sdir and $pdir after it has searched the directories
74 mentioned in libthread-db-search-path. If you want to search those
75 directories, they must be specified in libthread-db-search-path.
76 The default value of libthread-db-search-path on GNU/Linux and Solaris
77 systems is now "$sdir:$pdir".
79 $pdir is not supported by gdbserver, it is currently ignored.
80 $sdir is supported by gdbserver.
82 * New configure option --with-iconv-bin.
83 When using the internationalization support like the one in the GNU C
84 library, GDB will invoke the "iconv" program to get a list of supported
85 character sets. If this program lives in a non-standard location, one can
86 use this option to specify where to find it.
88 * When natively debugging programs on PowerPC BookE processors running
89 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
90 watchpoints, which specify a mask in addition to an address to watch.
91 The mask specifies that some bits of an address (the bits which are
92 reset in the mask) should be ignored when matching the address accessed
93 by the inferior against the watchpoint address. See the "PowerPC Embedded"
94 section in the user manual for more details.
96 * The new option --once causes GDBserver to stop listening for connections once
97 the first connection is made. The listening port used by GDBserver will
98 become available after that.
100 * New commands "info macros" and "alias" have been added.
102 * New function parameters suffix @entry specifies value of function parameter
103 at the time the function got called. Entry values are available only since
109 "!" is now an alias of the "shell" command.
110 Note that no space is needed between "!" and SHELL COMMAND.
114 watch EXPRESSION mask MASK_VALUE
115 The watch command now supports the mask argument which allows creation
116 of masked watchpoints, if the current architecture supports this feature.
118 info auto-load-scripts [REGEXP]
119 This command was formerly named "maintenance print section-scripts".
120 It is now generally useful and is no longer a maintenance-only command.
122 info macro [-all] [--] MACRO
123 The info macro command has new options `-all' and `--'. The first for
124 printing all definitions of a macro. The second for explicitly specifying
125 the end of arguments and the beginning of the macro name in case the macro
126 name starts with a hyphen.
128 collect[/s] EXPRESSIONS
129 The tracepoint collect command now takes an optional modifier "/s"
130 that directs it to dereference pointer-to-character types and
131 collect the bytes of memory up to a zero byte. The behavior is
132 similar to what you see when you use the regular print command on a
133 string. An optional integer following the "/s" sets a bound on the
134 number of bytes that will be collected.
137 The trace start command now interprets any supplied arguments as a
138 note to be recorded with the trace run, with an effect similar to
139 setting the variable trace-notes.
142 The trace stop command now interprets any arguments as a note to be
143 mentioned along with the tstatus report that the trace was stopped
144 with a command. The effect is similar to setting the variable
147 * Tracepoints can now be enabled and disabled at any time after a trace
148 experiment has been started using the standard "enable" and "disable"
149 commands. It is now possible to start a trace experiment with no enabled
150 tracepoints; GDB will display a warning, but will allow the experiment to
151 begin, assuming that tracepoints will be enabled as needed while the trace
154 * Fast tracepoints on 32-bit x86-architectures can now be placed at
155 locations with 4-byte instructions, when they were previously
156 limited to locations with instructions of 5 bytes or longer.
162 Set the GDB prompt, and allow escape sequences to be inserted to
163 display miscellaneous information (see 'help set extended-prompt'
164 for the list of sequences). This prompt (and any information
165 accessed through the escape sequences) is updated every time the
168 set print entry-values (both|compact|default|if-needed|no|only|preferred)
169 show print entry-values
170 Set printing of frame argument values at function entry. In some cases
171 GDB can determine the value of function argument which was passed by the
172 function caller, even if the value was modified inside the called function.
174 set debug entry-values
175 show debug entry-values
176 Control display of debugging info for determining frame argument values at
177 function entry and virtual tail call frames.
179 set basenames-may-differ
180 show basenames-may-differ
181 Set whether a source file may have multiple base names.
182 (A "base name" is the name of a file with the directory part removed.
183 Example: The base name of "/home/user/hello.c" is "hello.c".)
184 If set, GDB will canonicalize file names (e.g., expand symlinks)
185 before comparing them. Canonicalization is an expensive operation,
186 but it allows the same file be known by more than one base name.
187 If not set (the default), all source files are assumed to have just
188 one base name, and gdb will do file name comparisons more efficiently.
194 Set a user name and notes for the current and any future trace runs.
195 This is useful for long-running and/or disconnected traces, to
196 inform others (or yourself) as to who is running the trace, supply
197 contact information, or otherwise explain what is going on.
200 show trace-stop-notes
201 Set a note attached to the trace run, that is displayed when the
202 trace has been stopped by a tstop command. This is useful for
203 instance as an explanation, if you are stopping a trace run that was
204 started by someone else.
210 Dynamically enable a tracepoint in a started trace experiment.
214 Dynamically disable a tracepoint in a started trace experiment.
218 Set the user and notes of the trace run.
222 Query the current status of a tracepoint.
226 Query the minimum length of instruction at which a fast tracepoint may
229 * Dcache size (number of lines) and line-size are now runtime-configurable
230 via "set dcache line" and "set dcache line-size" commands.
234 Texas Instruments TMS320C6x tic6x-*-*
238 Renesas RL78 rl78-*-elf
240 *** Changes in GDB 7.3.1
242 * The build failure for NetBSD and OpenBSD targets have now been fixed.
244 *** Changes in GDB 7.3
246 * GDB has a new command: "thread find [REGEXP]".
247 It finds the thread id whose name, target id, or thread extra info
248 matches the given regular expression.
250 * The "catch syscall" command now works on mips*-linux* targets.
252 * The -data-disassemble MI command now supports modes 2 and 3 for
253 dumping the instruction opcodes.
255 * New command line options
257 -data-directory DIR Specify DIR as the "data-directory".
258 This is mostly for testing purposes.
260 * The "maint set python auto-load on|off" command has been renamed to
261 "set auto-load-scripts on|off".
263 * GDB has a new command: "set directories".
264 It is like the "dir" command except that it replaces the
265 source path list instead of augmenting it.
267 * GDB now understands thread names.
269 On GNU/Linux, "info threads" will display the thread name as set by
270 prctl or pthread_setname_np.
272 There is also a new command, "thread name", which can be used to
273 assign a name internally for GDB to display.
276 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
277 has been integrated into GDB.
281 ** The function gdb.Write now accepts an optional keyword 'stream'.
282 This keyword, when provided, will direct the output to either
283 stdout, stderr, or GDB's logging output.
285 ** Parameters can now be be sub-classed in Python, and in particular
286 you may implement the get_set_doc and get_show_doc functions.
287 This improves how Parameter set/show documentation is processed
288 and allows for more dynamic content.
290 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
291 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
292 have an is_valid method.
294 ** Breakpoints can now be sub-classed in Python, and in particular
295 you may implement a 'stop' function that is executed each time
296 the inferior reaches that breakpoint.
298 ** New function gdb.lookup_global_symbol looks up a global symbol.
300 ** GDB values in Python are now callable if the value represents a
301 function. For example, if 'some_value' represents a function that
302 takes two integer parameters and returns a value, you can call
303 that function like so:
305 result = some_value (10,20)
307 ** Module gdb.types has been added.
308 It contains a collection of utilities for working with gdb.Types objects:
309 get_basic_type, has_field, make_enum_dict.
311 ** Module gdb.printing has been added.
312 It contains utilities for writing and registering pretty-printers.
313 New classes: PrettyPrinter, SubPrettyPrinter,
314 RegexpCollectionPrettyPrinter.
315 New function: register_pretty_printer.
317 ** New commands "info pretty-printers", "enable pretty-printer" and
318 "disable pretty-printer" have been added.
320 ** gdb.parameter("directories") is now available.
322 ** New function gdb.newest_frame returns the newest frame in the
325 ** The gdb.InferiorThread class has a new "name" attribute. This
326 holds the thread's name.
328 ** Python Support for Inferior events.
329 Python scripts can add observers to be notified of events
330 occurring in the process being debugged.
331 The following events are currently supported:
332 - gdb.events.cont Continue event.
333 - gdb.events.exited Inferior exited event.
334 - gdb.events.stop Signal received, and Breakpoint hit events.
338 ** GDB now puts template parameters in scope when debugging in an
339 instantiation. For example, if you have:
341 template<int X> int func (void) { return X; }
343 then if you step into func<5>, "print X" will show "5". This
344 feature requires proper debuginfo support from the compiler; it
345 was added to GCC 4.5.
347 ** The motion commands "next", "finish", "until", and "advance" now
348 work better when exceptions are thrown. In particular, GDB will
349 no longer lose control of the inferior; instead, the GDB will
350 stop the inferior at the point at which the exception is caught.
351 This functionality requires a change in the exception handling
352 code that was introduced in GCC 4.5.
354 * GDB now follows GCC's rules on accessing volatile objects when
355 reading or writing target state during expression evaluation.
356 One notable difference to prior behavior is that "print x = 0"
357 no longer generates a read of x; the value of the assignment is
358 now always taken directly from the value being assigned.
360 * GDB now has some support for using labels in the program's source in
361 linespecs. For instance, you can use "advance label" to continue
362 execution to a label.
364 * GDB now has support for reading and writing a new .gdb_index
365 section. This section holds a fast index of DWARF debugging
366 information and can be used to greatly speed up GDB startup and
367 operation. See the documentation for `save gdb-index' for details.
369 * The "watch" command now accepts an optional "-location" argument.
370 When used, this causes GDB to watch the memory referred to by the
371 expression. Such a watchpoint is never deleted due to it going out
374 * GDB now supports thread debugging of core dumps on GNU/Linux.
376 GDB now activates thread debugging using the libthread_db library
377 when debugging GNU/Linux core dumps, similarly to when debugging
378 live processes. As a result, when debugging a core dump file, GDB
379 is now able to display pthread_t ids of threads. For example, "info
380 threads" shows the same output as when debugging the process when it
381 was live. In earlier releases, you'd see something like this:
384 * 1 LWP 6780 main () at main.c:10
386 While now you see this:
389 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
391 It is also now possible to inspect TLS variables when debugging core
394 When debugging a core dump generated on a machine other than the one
395 used to run GDB, you may need to point GDB at the correct
396 libthread_db library with the "set libthread-db-search-path"
397 command. See the user manual for more details on this command.
399 * When natively debugging programs on PowerPC BookE processors running
400 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
401 which stop execution of the inferior whenever it executes an instruction
402 at any address within the specified range. See the "PowerPC Embedded"
403 section in the user manual for more details.
405 * New features in the GDB remote stub, GDBserver
407 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
408 and i686 LynxOS (version 5.x).
410 ** GDBserver is now supported on Blackfin Linux.
412 * New native configurations
414 ia64 HP-UX ia64-*-hpux*
418 Analog Devices, Inc. Blackfin Processor bfin-*
420 * Ada task switching is now supported on sparc-elf targets when
421 debugging a program using the Ravenscar Profile. For more information,
422 see the "Tasking Support when using the Ravenscar Profile" section
423 in the GDB user manual.
425 * Guile support was removed.
427 * New features in the GNU simulator
429 ** The --map-info flag lists all known core mappings.
431 ** CFI flashes may be simulated via the "cfi" device.
433 *** Changes in GDB 7.2
435 * Shared library support for remote targets by default
437 When GDB is configured for a generic, non-OS specific target, like
438 for example, --target=arm-eabi or one of the many *-*-elf targets,
439 GDB now queries remote stubs for loaded shared libraries using the
440 `qXfer:libraries:read' packet. Previously, shared library support
441 was always disabled for such configurations.
445 ** Argument Dependent Lookup (ADL)
447 In C++ ADL lookup directs function search to the namespaces of its
448 arguments even if the namespace has not been imported.
458 Here the compiler will search for `foo' in the namespace of 'b'
459 and find A::foo. GDB now supports this. This construct is commonly
460 used in the Standard Template Library for operators.
462 ** Improved User Defined Operator Support
464 In addition to member operators, GDB now supports lookup of operators
465 defined in a namespace and imported with a `using' directive, operators
466 defined in the global scope, operators imported implicitly from an
467 anonymous namespace, and the ADL operators mentioned in the previous
469 GDB now also supports proper overload resolution for all the previously
470 mentioned flavors of operators.
472 ** static const class members
474 Printing of static const class members that are initialized in the
475 class definition has been fixed.
477 * Windows Thread Information Block access.
479 On Windows targets, GDB now supports displaying the Windows Thread
480 Information Block (TIB) structure. This structure is visible either
481 by using the new command `info w32 thread-information-block' or, by
482 dereferencing the new convenience variable named `$_tlb', a
483 thread-specific pointer to the TIB. This feature is also supported
484 when remote debugging using GDBserver.
488 Static tracepoints are calls in the user program into a tracing
489 library. One such library is a port of the LTTng kernel tracer to
490 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
491 When debugging with GDBserver, GDB now supports combining the GDB
492 tracepoint machinery with such libraries. For example: the user can
493 use GDB to probe a static tracepoint marker (a call from the user
494 program into the tracing library) with the new "strace" command (see
495 "New commands" below). This creates a "static tracepoint" in the
496 breakpoint list, that can be manipulated with the same feature set
497 as fast and regular tracepoints. E.g., collect registers, local and
498 global variables, collect trace state variables, and define
499 tracepoint conditions. In addition, the user can collect extra
500 static tracepoint marker specific data, by collecting the new
501 $_sdata internal variable. When analyzing the trace buffer, you can
502 inspect $_sdata like any other variable available to GDB. For more
503 information, see the "Tracepoints" chapter in GDB user manual. New
504 remote packets have been defined to support static tracepoints, see
505 the "New remote packets" section below.
507 * Better reconstruction of tracepoints after disconnected tracing
509 GDB will attempt to download the original source form of tracepoint
510 definitions when starting a trace run, and then will upload these
511 upon reconnection to the target, resulting in a more accurate
512 reconstruction of the tracepoints that are in use on the target.
516 You can now exercise direct control over the ways that GDB can
517 affect your program. For instance, you can disallow the setting of
518 breakpoints, so that the program can run continuously (assuming
519 non-stop mode). In addition, the "observer" variable is available
520 to switch all of the different controls; in observer mode, GDB
521 cannot affect the target's behavior at all, which is useful for
522 tasks like diagnosing live systems in the field.
524 * The new convenience variable $_thread holds the number of the
531 Return the address of the Windows Thread Information Block of a given thread.
535 In response to several of the tracepoint packets, the target may now
536 also respond with a number of intermediate `qRelocInsn' request
537 packets before the final result packet, to have GDB handle
538 relocating an instruction to execute at a different address. This
539 is particularly useful for stubs that support fast tracepoints. GDB
540 reports support for this feature in the qSupported packet.
544 List static tracepoint markers in the target program.
548 List static tracepoint markers at a given address in the target
551 qXfer:statictrace:read
553 Read the static trace data collected (by a `collect $_sdata'
554 tracepoint action). The remote stub reports support for this packet
555 to gdb's qSupported query.
559 Send the current settings of GDB's permission flags.
563 Send part of the source (textual) form of a tracepoint definition,
564 which includes location, conditional, and action list.
566 * The source command now accepts a -s option to force searching for the
567 script in the source search path even if the script name specifies
570 * New features in the GDB remote stub, GDBserver
572 - GDBserver now support tracepoints (including fast tracepoints, and
573 static tracepoints). The feature is currently supported by the
574 i386-linux and amd64-linux builds. See the "Tracepoints support
575 in gdbserver" section in the manual for more information.
577 GDBserver JIT compiles the tracepoint's conditional agent
578 expression bytecode into native code whenever possible for low
579 overhead dynamic tracepoints conditionals. For such tracepoints,
580 an expression that examines program state is evaluated when the
581 tracepoint is reached, in order to determine whether to capture
582 trace data. If the condition is simple and false, processing the
583 tracepoint finishes very quickly and no data is gathered.
585 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
586 for static tracepoints support.
588 - GDBserver now supports x86_64 Windows 64-bit debugging.
590 * GDB now sends xmlRegisters= in qSupported packet to indicate that
591 it understands register description.
593 * The --batch flag now disables pagination and queries.
595 * X86 general purpose registers
597 GDB now supports reading/writing byte, word and double-word x86
598 general purpose registers directly. This means you can use, say,
599 $ah or $ax to refer, respectively, to the byte register AH and
600 16-bit word register AX that are actually portions of the 32-bit
601 register EAX or 64-bit register RAX.
603 * The `commands' command now accepts a range of breakpoints to modify.
604 A plain `commands' following a command that creates multiple
605 breakpoints affects all the breakpoints set by that command. This
606 applies to breakpoints set by `rbreak', and also applies when a
607 single `break' command creates multiple breakpoints (e.g.,
608 breakpoints on overloaded c++ functions).
610 * The `rbreak' command now accepts a filename specification as part of
611 its argument, limiting the functions selected by the regex to those
612 in the specified file.
614 * Support for remote debugging Windows and SymbianOS shared libraries
615 from Unix hosts has been improved. Non Windows GDB builds now can
616 understand target reported file names that follow MS-DOS based file
617 system semantics, such as file names that include drive letters and
618 use the backslash character as directory separator. This makes it
619 possible to transparently use the "set sysroot" and "set
620 solib-search-path" on Unix hosts to point as host copies of the
621 target's shared libraries. See the new command "set
622 target-file-system-kind" described below, and the "Commands to
623 specify files" section in the user manual for more information.
627 eval template, expressions...
628 Convert the values of one or more expressions under the control
629 of the string template to a command line, and call it.
631 set target-file-system-kind unix|dos-based|auto
632 show target-file-system-kind
633 Set or show the assumed file system kind for target reported file
636 save breakpoints <filename>
637 Save all current breakpoint definitions to a file suitable for use
638 in a later debugging session. To read the saved breakpoint
639 definitions, use the `source' command.
641 `save tracepoints' is a new alias for `save-tracepoints'. The latter
644 info static-tracepoint-markers
645 Display information about static tracepoint markers in the target.
647 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
648 Define a static tracepoint by probing a marker at the given
649 function, line, address, or marker ID.
653 Enable and disable observer mode.
655 set may-write-registers on|off
656 set may-write-memory on|off
657 set may-insert-breakpoints on|off
658 set may-insert-tracepoints on|off
659 set may-insert-fast-tracepoints on|off
660 set may-interrupt on|off
661 Set individual permissions for GDB effects on the target. Note that
662 some of these settings can have undesirable or surprising
663 consequences, particularly when changed in the middle of a session.
664 For instance, disabling the writing of memory can prevent
665 breakpoints from being inserted, cause single-stepping to fail, or
666 even crash your program, if you disable after breakpoints have been
667 inserted. However, GDB should not crash.
669 set record memory-query on|off
670 show record memory-query
671 Control whether to stop the inferior if memory changes caused
672 by an instruction cannot be recorded.
677 The disassemble command now supports "start,+length" form of two arguments.
681 ** GDB now provides a new directory location, called the python directory,
682 where Python scripts written for GDB can be installed. The location
683 of that directory is <data-directory>/python, where <data-directory>
684 is the GDB data directory. For more details, see section `Scripting
685 GDB using Python' in the manual.
687 ** The GDB Python API now has access to breakpoints, symbols, symbol
688 tables, program spaces, inferiors, threads and frame's code blocks.
689 Additionally, GDB Parameters can now be created from the API, and
690 manipulated via set/show in the CLI.
692 ** New functions gdb.target_charset, gdb.target_wide_charset,
693 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
695 ** New exception gdb.GdbError.
697 ** Pretty-printers are now also looked up in the current program space.
699 ** Pretty-printers can now be individually enabled and disabled.
701 ** GDB now looks for names of Python scripts to auto-load in a
702 special section named `.debug_gdb_scripts', in addition to looking
703 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
705 * Tracepoint actions were unified with breakpoint commands. In particular,
706 there are no longer differences in "info break" output for breakpoints and
707 tracepoints and the "commands" command can be used for both tracepoints and
712 ARM Symbian arm*-*-symbianelf*
714 * D language support.
715 GDB now supports debugging programs written in the D programming
718 * GDB now supports the extended ptrace interface for PowerPC which is
719 available since Linux kernel version 2.6.34. This automatically enables
720 any hardware breakpoints and additional hardware watchpoints available in
721 the processor. The old ptrace interface exposes just one hardware
722 watchpoint and no hardware breakpoints.
724 * GDB is now able to use the Data Value Compare (DVC) register available on
725 embedded PowerPC processors to implement in hardware simple watchpoint
726 conditions of the form:
728 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
730 This works in native GDB running on Linux kernels with the extended ptrace
731 interface mentioned above.
733 *** Changes in GDB 7.1
739 GDB now supports importing of namespaces in C++. This enables the
740 user to inspect variables from imported namespaces. Support for
741 namepace aliasing has also been added. So, if a namespace is
742 aliased in the current scope (e.g. namepace C=A; ) the user can
743 print variables using the alias (e.g. (gdb) print C::x).
747 All known bugs relating to the printing of virtual base class were
748 fixed. It is now possible to call overloaded static methods using a
753 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
754 and reinterpret_cast<> are now handled by the C++ expression parser.
758 Xilinx MicroBlaze microblaze-*-*
763 Xilinx MicroBlaze microblaze
766 * Multi-program debugging.
768 GDB now has support for multi-program (a.k.a. multi-executable or
769 multi-exec) debugging. This allows for debugging multiple inferiors
770 simultaneously each running a different program under the same GDB
771 session. See "Debugging Multiple Inferiors and Programs" in the
772 manual for more information. This implied some user visible changes
773 in the multi-inferior support. For example, "info inferiors" now
774 lists inferiors that are not running yet or that have exited
775 already. See also "New commands" and "New options" below.
777 * New tracing features
779 GDB's tracepoint facility now includes several new features:
781 ** Trace state variables
783 GDB tracepoints now include support for trace state variables, which
784 are variables managed by the target agent during a tracing
785 experiment. They are useful for tracepoints that trigger each
786 other, so for instance one tracepoint can count hits in a variable,
787 and then a second tracepoint has a condition that is true when the
788 count reaches a particular value. Trace state variables share the
789 $-syntax of GDB convenience variables, and can appear in both
790 tracepoint actions and condition expressions. Use the "tvariable"
791 command to create, and "info tvariables" to view; see "Trace State
792 Variables" in the manual for more detail.
796 GDB now includes an option for defining fast tracepoints, which
797 targets may implement more efficiently, such as by installing a jump
798 into the target agent rather than a trap instruction. The resulting
799 speedup can be by two orders of magnitude or more, although the
800 tradeoff is that some program locations on some target architectures
801 might not allow fast tracepoint installation, for instance if the
802 instruction to be replaced is shorter than the jump. To request a
803 fast tracepoint, use the "ftrace" command, with syntax identical to
804 the regular trace command.
806 ** Disconnected tracing
808 It is now possible to detach GDB from the target while it is running
809 a trace experiment, then reconnect later to see how the experiment
810 is going. In addition, a new variable disconnected-tracing lets you
811 tell the target agent whether to continue running a trace if the
812 connection is lost unexpectedly.
816 GDB now has the ability to save the trace buffer into a file, and
817 then use that file as a target, similarly to you can do with
818 corefiles. You can select trace frames, print data that was
819 collected in them, and use tstatus to display the state of the
820 tracing run at the moment that it was saved. To create a trace
821 file, use "tsave <filename>", and to use it, do "target tfile
824 ** Circular trace buffer
826 You can ask the target agent to handle the trace buffer as a
827 circular buffer, discarding the oldest trace frames to make room for
828 newer ones, by setting circular-trace-buffer to on. This feature may
829 not be available for all target agents.
834 The disassemble command, when invoked with two arguments, now requires
835 the arguments to be comma-separated.
838 The info variables command now displays variable definitions. Files
839 which only declare a variable are not shown.
842 The source command is now capable of sourcing Python scripts.
843 This feature is dependent on the debugger being build with Python
846 Related to this enhancement is also the introduction of a new command
847 "set script-extension" (see below).
849 * New commands (for set/show, see "New options" below)
851 record save [<FILENAME>]
852 Save a file (in core file format) containing the process record
853 execution log for replay debugging at a later time.
855 record restore <FILENAME>
856 Restore the process record execution log that was saved at an
857 earlier time, for replay debugging.
859 add-inferior [-copies <N>] [-exec <FILENAME>]
862 clone-inferior [-copies <N>] [ID]
863 Make a new inferior ready to execute the same program another
869 maint info program-spaces
870 List the program spaces loaded into GDB.
872 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
873 show remote interrupt-sequence
874 Allow the user to select one of ^C, a BREAK signal or BREAK-g
875 as the sequence to the remote target in order to interrupt the execution.
876 Ctrl-C is a default. Some system prefers BREAK which is high level of
877 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
878 Magic SysRq g. It is BREAK signal and character 'g'.
880 set remote interrupt-on-connect [on | off]
881 show remote interrupt-on-connect
882 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
883 remote target when gdb connects to it. This is needed when you debug
886 set remotebreak [on | off]
888 Deprecated. Use "set/show remote interrupt-sequence" instead.
890 tvariable $NAME [ = EXP ]
891 Create or modify a trace state variable.
894 List trace state variables and their values.
896 delete tvariable $NAME ...
897 Delete one or more trace state variables.
900 Evaluate the given expressions without collecting anything into the
901 trace buffer. (Valid in tracepoint actions only.)
903 ftrace FN / FILE:LINE / *ADDR
904 Define a fast tracepoint at the given function, line, or address.
906 * New expression syntax
908 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
909 GDB now parses 0b101010 identically with 42.
913 set follow-exec-mode new|same
914 show follow-exec-mode
915 Control whether GDB reuses the same inferior across an exec call or
916 creates a new one. This is useful to be able to restart the old
917 executable after the inferior having done an exec call.
919 set default-collect EXPR, ...
921 Define a list of expressions to be collected at each tracepoint.
922 This is a useful way to ensure essential items are not overlooked,
923 such as registers or a critical global variable.
925 set disconnected-tracing
926 show disconnected-tracing
927 If set to 1, the target is instructed to continue tracing if it
928 loses its connection to GDB. If 0, the target is to stop tracing
931 set circular-trace-buffer
932 show circular-trace-buffer
933 If set to on, the target is instructed to use a circular trace buffer
934 and discard the oldest trace frames instead of stopping the trace due
935 to a full trace buffer. If set to off, the trace stops when the buffer
936 fills up. Some targets may not support this.
938 set script-extension off|soft|strict
939 show script-extension
940 If set to "off", the debugger does not perform any script language
941 recognition, and all sourced files are assumed to be GDB scripts.
942 If set to "soft" (the default), files are sourced according to
943 filename extension, falling back to GDB scripts if the first
945 If set to "strict", files are sourced according to filename extension.
947 set ada trust-PAD-over-XVS on|off
948 show ada trust-PAD-over-XVS
949 If off, activate a workaround against a bug in the debugging information
950 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
951 the GCC sources for more information about the GNAT encoding and
952 PAD types in particular). It is always safe to set this option to
953 off, but this introduces a slight performance penalty. The default
956 * Python API Improvements
958 ** GDB provides the new class gdb.LazyString. This is useful in
959 some pretty-printing cases. The new method gdb.Value.lazy_string
960 provides a simple way to create objects of this type.
962 ** The fields returned by gdb.Type.fields now have an
963 `is_base_class' attribute.
965 ** The new method gdb.Type.range returns the range of an array type.
967 ** The new method gdb.parse_and_eval can be used to parse and
968 evaluate an expression.
973 Define a trace state variable.
976 Get the current value of a trace state variable.
979 Set desired tracing behavior upon disconnection.
982 Set the trace buffer to be linear or circular.
985 Get data about the tracepoints currently in use.
989 Process record now works correctly with hardware watchpoints.
991 Multiple bug fixes have been made to the mips-irix port, making it
992 much more reliable. In particular:
993 - Debugging threaded applications is now possible again. Previously,
994 GDB would hang while starting the program, or while waiting for
995 the program to stop at a breakpoint.
996 - Attaching to a running process no longer hangs.
997 - An error occurring while loading a core file has been fixed.
998 - Changing the value of the PC register now works again. This fixes
999 problems observed when using the "jump" command, or when calling
1000 a function from GDB, or even when assigning a new value to $pc.
1001 - With the "finish" and "return" commands, the return value for functions
1002 returning a small array is now correctly printed.
1003 - It is now possible to break on shared library code which gets executed
1004 during a shared library init phase (code executed while executing
1005 their .init section). Previously, the breakpoint would have no effect.
1006 - GDB is now able to backtrace through the signal handler for
1007 non-threaded programs.
1009 PIE (Position Independent Executable) programs debugging is now supported.
1010 This includes debugging execution of PIC (Position Independent Code) shared
1011 libraries although for that, it should be possible to run such libraries as an
1014 *** Changes in GDB 7.0
1016 * GDB now has an interface for JIT compilation. Applications that
1017 dynamically generate code can create symbol files in memory and register
1018 them with GDB. For users, the feature should work transparently, and
1019 for JIT developers, the interface is documented in the GDB manual in the
1020 "JIT Compilation Interface" chapter.
1022 * Tracepoints may now be conditional. The syntax is as for
1023 breakpoints; either an "if" clause appended to the "trace" command,
1024 or the "condition" command is available. GDB sends the condition to
1025 the target for evaluation using the same bytecode format as is used
1026 for tracepoint actions.
1028 * The disassemble command now supports: an optional /r modifier, print the
1029 raw instructions in hex as well as in symbolic form, and an optional /m
1030 modifier to print mixed source+assembly.
1032 * Process record and replay
1034 In a architecture environment that supports ``process record and
1035 replay'', ``process record and replay'' target can record a log of
1036 the process execution, and replay it with both forward and reverse
1039 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1040 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1041 set execution-direction {forward|reverse}, for targets that support
1044 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1045 feature is available with a native GDB running on kernel version
1048 * GDB now has support for multi-byte and wide character sets on the
1049 target. Strings whose character type is wchar_t, char16_t, or
1050 char32_t are now correctly printed. GDB supports wide- and unicode-
1051 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1052 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1053 `printf'. This feature requires iconv to work properly; if your
1054 system does not have a working iconv, GDB can use GNU libiconv. See
1055 the installation instructions for more information.
1057 * GDB now supports automatic retrieval of shared library files from
1058 remote targets. To use this feature, specify a system root that begins
1059 with the `remote:' prefix, either via the `set sysroot' command or via
1060 the `--with-sysroot' configure-time option.
1062 * "info sharedlibrary" now takes an optional regex of libraries to show,
1063 and it now reports if a shared library has no debugging information.
1065 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1066 now complete on file names.
1068 * When completing in expressions, gdb will attempt to limit
1069 completions to allowable structure or union fields, where appropriate.
1070 For instance, consider:
1072 # struct example { int f1; double f2; };
1073 # struct example variable;
1076 If the user types TAB at the end of this command line, the available
1077 completions will be "f1" and "f2".
1079 * Inlined functions are now supported. They show up in backtraces, and
1080 the "step", "next", and "finish" commands handle them automatically.
1082 * GDB now supports the token-splicing (##) and stringification (#)
1083 operators when expanding macros. It also supports variable-arity
1086 * GDB now supports inspecting extra signal information, exported by
1087 the new $_siginfo convenience variable. The feature is currently
1088 implemented on linux ARM, i386 and amd64.
1090 * GDB can now display the VFP floating point registers and NEON vector
1091 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1092 can provide these registers (requires Linux 2.6.30 or later). Remote
1093 and simulator targets may also provide them.
1095 * New remote packets
1098 Search memory for a sequence of bytes.
1101 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1102 operation over reliable transport links. Use of this packet is
1103 controlled by the `set remote noack-packet' command.
1106 Kill the process with the specified process ID. Use this in preference
1107 to `k' when multiprocess protocol extensions are supported.
1110 Obtains additional operating system information
1114 Read or write additional signal information.
1116 * Removed remote protocol undocumented extension
1118 An undocumented extension to the remote protocol's `S' stop reply
1119 packet that permited the stub to pass a process id was removed.
1120 Remote servers should use the `T' stop reply packet instead.
1122 * GDB now supports multiple function calling conventions according to the
1123 DWARF-2 DW_AT_calling_convention function attribute.
1125 * The SH target utilizes the aforementioned change to distinguish between gcc
1126 and Renesas calling convention. It also adds the new CLI commands
1127 `set/show sh calling-convention'.
1129 * GDB can now read compressed debug sections, as produced by GNU gold
1130 with the --compress-debug-sections=zlib flag.
1132 * 64-bit core files are now supported on AIX.
1134 * Thread switching is now supported on Tru64.
1136 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1137 which will be allocated using malloc later in program execution.
1139 * The qXfer:libraries:read remote procotol packet now allows passing a
1140 list of section offsets.
1142 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1143 conditions handling signals delivered during attach or thread creation
1144 have also been fixed.
1146 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1147 From the user's standpoint, all unqualified instances of True and False
1148 are treated as the standard definitions, regardless of context.
1150 * GDB now parses C++ symbol and type names more flexibly. For
1153 template<typename T> class C { };
1156 GDB will now correctly handle all of:
1158 ptype C<char const *>
1159 ptype C<char const*>
1160 ptype C<const char *>
1161 ptype C<const char*>
1163 * New features in the GDB remote stub, gdbserver
1165 - The "--wrapper" command-line argument tells gdbserver to use a
1166 wrapper program to launch programs for debugging.
1168 - On PowerPC and S/390 targets, it is now possible to use a single
1169 gdbserver executable to debug both 32-bit and 64-bit programs.
1170 (This requires gdbserver itself to be built as a 64-bit executable.)
1172 - gdbserver uses the new noack protocol mode for TCP connections to
1173 reduce communications latency, if also supported and enabled in GDB.
1175 - Support for the sparc64-linux-gnu target is now included in
1178 - The amd64-linux build of gdbserver now supports debugging both
1179 32-bit and 64-bit programs.
1181 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1182 now support hardware watchpoints, and will use them automatically
1187 GDB now has support for scripting using Python. Whether this is
1188 available is determined at configure time.
1190 New GDB commands can now be written in Python.
1192 * Ada tasking support
1194 Ada tasks can now be inspected in GDB. The following commands have
1198 Print the list of Ada tasks.
1200 Print detailed information about task number N.
1202 Print the task number of the current task.
1204 Switch the context of debugging to task number N.
1206 * Support for user-defined prefixed commands. The "define" command can
1207 add new commands to existing prefixes, e.g. "target".
1209 * Multi-inferior, multi-process debugging.
1211 GDB now has generalized support for multi-inferior debugging. See
1212 "Debugging Multiple Inferiors" in the manual for more information.
1213 Although availability still depends on target support, the command
1214 set is more uniform now. The GNU/Linux specific multi-forks support
1215 has been migrated to this new framework. This implied some user
1216 visible changes; see "New commands" and also "Removed commands"
1219 * Target descriptions can now describe the target OS ABI. See the
1220 "Target Description Format" section in the user manual for more
1223 * Target descriptions can now describe "compatible" architectures
1224 to indicate that the target can execute applications for a different
1225 architecture in addition to those for the main target architecture.
1226 See the "Target Description Format" section in the user manual for
1229 * Multi-architecture debugging.
1231 GDB now includes general supports for debugging applications on
1232 hybrid systems that use more than one single processor architecture
1233 at the same time. Each such hybrid architecture still requires
1234 specific support to be added. The only hybrid architecture supported
1235 in this version of GDB is the Cell Broadband Engine.
1237 * GDB now supports integrated debugging of Cell/B.E. applications that
1238 use both the PPU and SPU architectures. To enable support for hybrid
1239 Cell/B.E. debugging, you need to configure GDB to support both the
1240 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1241 --enable-targets configure option.
1243 * Non-stop mode debugging.
1245 For some targets, GDB now supports an optional mode of operation in
1246 which you can examine stopped threads while other threads continue
1247 to execute freely. This is referred to as non-stop mode, with the
1248 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1249 section in the user manual for more information.
1251 To be able to support remote non-stop debugging, a remote stub needs
1252 to implement the non-stop mode remote protocol extensions, as
1253 described in the "Remote Non-Stop" section of the user manual. The
1254 GDB remote stub, gdbserver, has been adjusted to support these
1255 extensions on linux targets.
1257 * New commands (for set/show, see "New options" below)
1259 catch syscall [NAME(S) | NUMBER(S)]
1260 Catch system calls. Arguments, which should be names of system
1261 calls or their numbers, mean catch only those syscalls. Without
1262 arguments, every syscall will be caught. When the inferior issues
1263 any of the specified syscalls, GDB will stop and announce the system
1264 call, both when it is called and when its call returns. This
1265 feature is currently available with a native GDB running on the
1266 Linux Kernel, under the following architectures: x86, x86_64,
1267 PowerPC and PowerPC64.
1269 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1271 Search memory for a sequence of bytes.
1273 maint set python print-stack
1274 maint show python print-stack
1275 Show a stack trace when an error is encountered in a Python script.
1278 Invoke CODE by passing it to the Python interpreter.
1283 These allow macros to be defined, undefined, and listed
1287 Show operating system information about processes.
1290 List the inferiors currently under GDB's control.
1293 Switch focus to inferior number NUM.
1296 Detach from inferior number NUM.
1299 Kill inferior number NUM.
1303 set spu stop-on-load
1304 show spu stop-on-load
1305 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1307 set spu auto-flush-cache
1308 show spu auto-flush-cache
1309 Control whether to automatically flush the software-managed cache
1310 during Cell/B.E. debugging.
1312 set sh calling-convention
1313 show sh calling-convention
1314 Control the calling convention used when calling SH target functions.
1317 show debug timestamp
1318 Control display of timestamps with GDB debugging output.
1320 set disassemble-next-line
1321 show disassemble-next-line
1322 Control display of disassembled source lines or instructions when
1325 set remote noack-packet
1326 show remote noack-packet
1327 Set/show the use of remote protocol QStartNoAckMode packet. See above
1328 under "New remote packets."
1330 set remote query-attached-packet
1331 show remote query-attached-packet
1332 Control use of remote protocol `qAttached' (query-attached) packet.
1334 set remote read-siginfo-object
1335 show remote read-siginfo-object
1336 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1339 set remote write-siginfo-object
1340 show remote write-siginfo-object
1341 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1344 set remote reverse-continue
1345 show remote reverse-continue
1346 Control use of remote protocol 'bc' (reverse-continue) packet.
1348 set remote reverse-step
1349 show remote reverse-step
1350 Control use of remote protocol 'bs' (reverse-step) packet.
1352 set displaced-stepping
1353 show displaced-stepping
1354 Control displaced stepping mode. Displaced stepping is a way to
1355 single-step over breakpoints without removing them from the debuggee.
1356 Also known as "out-of-line single-stepping".
1359 show debug displaced
1360 Control display of debugging info for displaced stepping.
1362 maint set internal-error
1363 maint show internal-error
1364 Control what GDB does when an internal error is detected.
1366 maint set internal-warning
1367 maint show internal-warning
1368 Control what GDB does when an internal warning is detected.
1373 Use a wrapper program to launch programs for debugging.
1375 set multiple-symbols (all|ask|cancel)
1376 show multiple-symbols
1377 The value of this variable can be changed to adjust the debugger behavior
1378 when an expression or a breakpoint location contains an ambiguous symbol
1379 name (an overloaded function name, for instance).
1381 set breakpoint always-inserted
1382 show breakpoint always-inserted
1383 Keep breakpoints always inserted in the target, as opposed to inserting
1384 them when resuming the target, and removing them when the target stops.
1385 This option can improve debugger performance on slow remote targets.
1387 set arm fallback-mode (arm|thumb|auto)
1388 show arm fallback-mode
1389 set arm force-mode (arm|thumb|auto)
1391 These commands control how ARM GDB determines whether instructions
1392 are ARM or Thumb. The default for both settings is auto, which uses
1393 the current CPSR value for instructions without symbols; previous
1394 versions of GDB behaved as if "set arm fallback-mode arm".
1396 set disable-randomization
1397 show disable-randomization
1398 Standalone programs run with the virtual address space randomization enabled
1399 by default on some platforms. This option keeps the addresses stable across
1400 multiple debugging sessions.
1404 Control whether other threads are stopped or not when some thread hits
1409 Requests that asynchronous execution is enabled in the target, if available.
1410 In this case, it's possible to resume target in the background, and interact
1411 with GDB while the target is running. "show target-async" displays the
1412 current state of asynchronous execution of the target.
1414 set target-wide-charset
1415 show target-wide-charset
1416 The target-wide-charset is the name of the character set that GDB
1417 uses when printing characters whose type is wchar_t.
1419 set tcp auto-retry (on|off)
1421 set tcp connect-timeout
1422 show tcp connect-timeout
1423 These commands allow GDB to retry failed TCP connections to a remote stub
1424 with a specified timeout period; this is useful if the stub is launched
1425 in parallel with GDB but may not be ready to accept connections immediately.
1427 set libthread-db-search-path
1428 show libthread-db-search-path
1429 Control list of directories which GDB will search for appropriate
1432 set schedule-multiple (on|off)
1433 show schedule-multiple
1434 Allow GDB to resume all threads of all processes or only threads of
1435 the current process.
1439 Use more aggressive caching for accesses to the stack. This improves
1440 performance of remote debugging (particularly backtraces) without
1441 affecting correctness.
1443 set interactive-mode (on|off|auto)
1444 show interactive-mode
1445 Control whether GDB runs in interactive mode (on) or not (off).
1446 When in interactive mode, GDB waits for the user to answer all
1447 queries. Otherwise, GDB does not wait and assumes the default
1448 answer. When set to auto (the default), GDB determines which
1449 mode to use based on the stdin settings.
1454 For program forks, this is replaced by the new more generic `info
1455 inferiors' command. To list checkpoints, you can still use the
1456 `info checkpoints' command, which was an alias for the `info forks'
1460 Replaced by the new `inferior' command. To switch between
1461 checkpoints, you can still use the `restart' command, which was an
1462 alias for the `fork' command.
1465 This is removed, since some targets don't have a notion of
1466 processes. To switch between processes, you can still use the
1467 `inferior' command using GDB's own inferior number.
1470 For program forks, this is replaced by the new more generic `kill
1471 inferior' command. To delete a checkpoint, you can still use the
1472 `delete checkpoint' command, which was an alias for the `delete
1476 For program forks, this is replaced by the new more generic `detach
1477 inferior' command. To detach a checkpoint, you can still use the
1478 `detach checkpoint' command, which was an alias for the `detach
1481 * New native configurations
1483 x86/x86_64 Darwin i[34567]86-*-darwin*
1485 x86_64 MinGW x86_64-*-mingw*
1489 Lattice Mico32 lm32-*
1490 x86 DICOS i[34567]86-*-dicos*
1491 x86_64 DICOS x86_64-*-dicos*
1494 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1495 (mingw32ce) debugging.
1501 These commands were actually not implemented on any target.
1503 *** Changes in GDB 6.8
1505 * New native configurations
1507 NetBSD/hppa hppa*-*netbsd*
1508 Xtensa GNU/Linux xtensa*-*-linux*
1512 NetBSD/hppa hppa*-*-netbsd*
1513 Xtensa GNU/Lunux xtensa*-*-linux*
1515 * Change in command line behavior -- corefiles vs. process ids.
1517 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1518 attaching to process NUMBER fails, GDB no longer attempts to open a
1519 core file named NUMBER. Attaching to a program using the -c option
1520 is no longer supported. Instead, use the '-p' or '--pid' options.
1522 * GDB can now be built as a native debugger for debugging Windows x86
1523 (mingw32) Portable Executable (PE) programs.
1525 * Pending breakpoints no longer change their number when their address
1528 * GDB now supports breakpoints with multiple locations,
1529 including breakpoints on C++ constructors, inside C++ templates,
1530 and in inlined functions.
1532 * GDB's ability to debug optimized code has been improved. GDB more
1533 accurately identifies function bodies and lexical blocks that occupy
1534 more than one contiguous range of addresses.
1536 * Target descriptions can now describe registers for PowerPC.
1538 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1539 registers on PowerPC targets.
1541 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1542 targets even when the libthread_db library is not available.
1544 * The GDB remote stub, gdbserver, now supports the new file transfer
1545 commands (remote put, remote get, and remote delete).
1547 * The GDB remote stub, gdbserver, now supports run and attach in
1548 extended-remote mode.
1550 * hppa*64*-*-hpux11* target broken
1551 The debugger is unable to start a program and fails with the following
1552 error: "Error trying to get information about dynamic linker".
1553 The gdb-6.7 release is also affected.
1555 * GDB now supports the --enable-targets= configure option to allow
1556 building a single GDB executable that supports multiple remote
1557 target architectures.
1559 * GDB now supports debugging C and C++ programs which use the
1560 Decimal Floating Point extension. In addition, the PowerPC target
1561 now has a set of pseudo-registers to inspect decimal float values
1562 stored in two consecutive float registers.
1564 * The -break-insert MI command can optionally create pending
1567 * Improved support for debugging Ada
1568 Many improvements to the Ada language support have been made. These
1570 - Better support for Ada2005 interface types
1571 - Improved handling of arrays and slices in general
1572 - Better support for Taft-amendment types
1573 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1575 - Improved command completion in Ada
1578 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1583 set print frame-arguments (all|scalars|none)
1584 show print frame-arguments
1585 The value of this variable can be changed to control which argument
1586 values should be printed by the debugger when displaying a frame.
1591 Transfer files to and from a remote target, and delete remote files.
1598 Transfer files to and from a remote target, and delete remote files.
1600 * New remote packets
1607 Open, close, read, write, and delete files on the remote system.
1610 Attach to an existing process on the remote system, in extended-remote
1614 Run a new process on the remote system, in extended-remote mode.
1616 *** Changes in GDB 6.7
1618 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1619 bfd, libiberty and opcodes, as revealed by static analysis donated by
1620 Coverity, Inc. (http://scan.coverity.com).
1622 * When looking up multiply-defined global symbols, GDB will now prefer the
1623 symbol definition in the current shared library if it was built using the
1624 -Bsymbolic linker option.
1626 * When the Text User Interface (TUI) is not configured, GDB will now
1627 recognize the -tui command-line option and print a message that the TUI
1630 * The GDB remote stub, gdbserver, now has lower overhead for high
1631 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1633 * GDB for MIPS targets now autodetects whether a remote target provides
1634 32-bit or 64-bit register values.
1636 * Support for C++ member pointers has been improved.
1638 * GDB now understands XML target descriptions, which specify the
1639 target's overall architecture. GDB can read a description from
1640 a local file or over the remote serial protocol.
1642 * Vectors of single-byte data use a new integer type which is not
1643 automatically displayed as character or string data.
1645 * The /s format now works with the print command. It displays
1646 arrays of single-byte integers and pointers to single-byte integers
1649 * Target descriptions can now describe target-specific registers,
1650 for architectures which have implemented the support (currently
1651 only ARM, M68K, and MIPS).
1653 * GDB and the GDB remote stub, gdbserver, now support the XScale
1656 * The GDB remote stub, gdbserver, has been updated to support
1657 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1658 has been rewritten to use the standard GDB remote protocol.
1660 * GDB can now step into C++ functions which are called through thunks.
1662 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1664 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1665 layout. It also supports a TextSeg= and DataSeg= response when only
1666 segment base addresses (rather than offsets) are available.
1668 * The /i format now outputs any trailing branch delay slot instructions
1669 immediately following the last instruction within the count specified.
1671 * The GDB remote protocol "T" stop reply packet now supports a
1672 "library" response. Combined with the new "qXfer:libraries:read"
1673 packet, this response allows GDB to debug shared libraries on targets
1674 where the operating system manages the list of loaded libraries (e.g.
1675 Windows and SymbianOS).
1677 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1678 (DLLs) on Windows and Windows CE targets.
1680 * GDB now supports a faster verification that a .debug file matches its binary
1681 according to its build-id signature, if the signature is present.
1687 Enable or disable hardware flow control (RTS/CTS) on the serial port
1688 when debugging using remote targets.
1690 set mem inaccessible-by-default
1691 show mem inaccessible-by-default
1692 If the target supplies a memory map, for instance via the remote
1693 protocol's "qXfer:memory-map:read" packet, setting this variable
1694 prevents GDB from accessing memory outside the memory map. This
1695 is useful for targets with memory mapped registers or which react
1696 badly to accesses of unmapped address space.
1698 set breakpoint auto-hw
1699 show breakpoint auto-hw
1700 If the target supplies a memory map, for instance via the remote
1701 protocol's "qXfer:memory-map:read" packet, setting this variable
1702 lets GDB use hardware breakpoints automatically for memory regions
1703 where it can not use software breakpoints. This covers both the
1704 "break" command and internal breakpoints used for other commands
1705 including "next" and "finish".
1708 catch exception unhandled
1709 Stop the program execution when Ada exceptions are raised.
1712 Stop the program execution when an Ada assertion failed.
1716 Set an alternate system root for target files. This is a more
1717 general version of "set solib-absolute-prefix", which is now
1718 an alias to "set sysroot".
1721 Provide extended SPU facility status information. This set of
1722 commands is available only when debugging the Cell/B.E. SPU
1725 * New native configurations
1727 OpenBSD/sh sh*-*openbsd*
1730 unset tdesc filename
1732 Use the specified local file as an XML target description, and do
1733 not query the target for its built-in description.
1737 OpenBSD/sh sh*-*-openbsd*
1738 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1739 Toshiba Media Processor mep-elf
1741 * New remote packets
1744 Ignore the specified signals; pass them directly to the debugged program
1745 without stopping other threads or reporting them to GDB.
1747 qXfer:features:read:
1748 Read an XML target description from the target, which describes its
1753 Read or write contents of an spufs file on the target system. These
1754 packets are available only on the Cell/B.E. SPU architecture.
1756 qXfer:libraries:read:
1757 Report the loaded shared libraries. Combined with new "T" packet
1758 response, this packet allows GDB to debug shared libraries on
1759 targets where the operating system manages the list of loaded
1760 libraries (e.g. Windows and SymbianOS).
1764 Support for these obsolete configurations has been removed.
1772 i[34567]86-*-lynxos*
1773 i[34567]86-*-netware*
1774 i[34567]86-*-sco3.2v5*
1775 i[34567]86-*-sco3.2v4*
1777 i[34567]86-*-sysv4.2*
1780 i[34567]86-*-unixware2*
1781 i[34567]86-*-unixware*
1790 * Other removed features
1797 Various m68k-only ROM monitors.
1804 Various Renesas ROM monitors and debugging interfaces for SH and
1809 Support for a Macraigor serial interface to on-chip debugging.
1810 GDB does not directly support the newer parallel or USB
1815 A debug information format. The predecessor to DWARF 2 and
1816 DWARF 3, which are still supported.
1818 Support for the HP aCC compiler on HP-UX/PA-RISC
1820 SOM-encapsulated symbolic debugging information, automatic
1821 invocation of pxdb, and the aCC custom C++ ABI. This does not
1822 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1823 with aCC can still be debugged on an assembly level.
1825 MIPS ".pdr" sections
1827 A MIPS-specific format used to describe stack frame layout
1828 in debugging information.
1832 GDB could work with an older version of Guile to debug
1833 the interpreter and Scheme programs running in it.
1835 set mips stack-arg-size
1836 set mips saved-gpreg-size
1838 Use "set mips abi" to control parameter passing for MIPS.
1840 *** Changes in GDB 6.6
1845 Cell Broadband Engine SPU spu-elf
1847 * GDB can now be configured as a cross-debugger targeting native Windows
1848 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1849 running on a Windows system over TCP/IP to debug Windows programs.
1851 * The GDB remote stub, gdbserver, has been updated to support Windows and
1852 Cygwin debugging. Both single-threaded and multi-threaded programs are
1855 * The "set trust-readonly-sections" command works again. This command was
1856 broken in GDB 6.3, 6.4, and 6.5.
1858 * The "load" command now supports writing to flash memory, if the remote
1859 stub provides the required support.
1861 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1862 longer requires symbolic debug information (e.g. DWARF-2).
1867 unset substitute-path
1868 show substitute-path
1869 Manage a list of substitution rules that GDB uses to rewrite the name
1870 of the directories where the sources are located. This can be useful
1871 for instance when the sources were moved to a different location
1872 between compilation and debugging.
1876 Print each CLI command as it is executed. Each command is prefixed with
1877 a number of `+' symbols representing the nesting depth.
1878 The source command now has a `-v' option to enable the same feature.
1882 The ARM Demon monitor support (RDP protocol, "target rdp").
1884 Kernel Object Display, an embedded debugging feature which only worked with
1885 an obsolete version of Cisco IOS.
1887 The 'set download-write-size' and 'show download-write-size' commands.
1889 * New remote packets
1892 Tell a stub about GDB client features, and request remote target features.
1893 The first feature implemented is PacketSize, which allows the target to
1894 specify the size of packets it can handle - to minimize the number of
1895 packets required and improve performance when connected to a remote
1899 Fetch an OS auxilliary vector from the remote stub. This packet is a
1900 more efficient replacement for qPart:auxv:read.
1902 qXfer:memory-map:read:
1903 Fetch a memory map from the remote stub, including information about
1904 RAM, ROM, and flash memory devices.
1909 Erase and program a flash memory device.
1911 * Removed remote packets
1914 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1915 used it, and only gdbserver implemented it.
1917 *** Changes in GDB 6.5
1921 Renesas M32C/M16C m32c-elf
1923 Morpho Technologies ms1 ms1-elf
1927 init-if-undefined Initialize a convenience variable, but
1928 only if it doesn't already have a value.
1930 The following commands are presently only implemented for native GNU/Linux:
1932 checkpoint Save a snapshot of the program state.
1934 restart <n> Return the program state to a
1935 previously saved state.
1937 info checkpoints List currently saved checkpoints.
1939 delete-checkpoint <n> Delete a previously saved checkpoint.
1941 set|show detach-on-fork Tell gdb whether to detach from a newly
1942 forked process, or to keep debugging it.
1944 info forks List forks of the user program that
1945 are available to be debugged.
1947 fork <n> Switch to debugging one of several
1948 forks of the user program that are
1949 available to be debugged.
1951 delete-fork <n> Delete a fork from the list of forks
1952 that are available to be debugged (and
1953 kill the forked process).
1955 detach-fork <n> Delete a fork from the list of forks
1956 that are available to be debugged (and
1957 allow the process to continue).
1961 Morpho Technologies ms2 ms1-elf
1963 * Improved Windows host support
1965 GDB now builds as a cross debugger hosted on i686-mingw32, including
1966 native console support, and remote communications using either
1967 network sockets or serial ports.
1969 * Improved Modula-2 language support
1971 GDB can now print most types in the Modula-2 syntax. This includes:
1972 basic types, set types, record types, enumerated types, range types,
1973 pointer types and ARRAY types. Procedure var parameters are correctly
1974 printed and hexadecimal addresses and character constants are also
1975 written in the Modula-2 syntax. Best results can be obtained by using
1976 GNU Modula-2 together with the -gdwarf-2 command line option.
1980 The ARM rdi-share module.
1982 The Netware NLM debug server.
1984 *** Changes in GDB 6.4
1986 * New native configurations
1988 OpenBSD/arm arm*-*-openbsd*
1989 OpenBSD/mips64 mips64-*-openbsd*
1993 Morpho Technologies ms1 ms1-elf
1995 * New command line options
1997 --batch-silent As for --batch, but totally silent.
1998 --return-child-result The debugger will exist with the same value
1999 the child (debugged) program exited with.
2000 --eval-command COMMAND, -ex COMMAND
2001 Execute a single GDB CLI command. This may be
2002 specified multiple times and in conjunction
2003 with the --command (-x) option.
2005 * Deprecated commands removed
2007 The following commands, that were deprecated in 2000, have been
2011 set|show arm disassembly-flavor set|show arm disassembler
2012 othernames set arm disassembler
2013 set|show remotedebug set|show debug remote
2014 set|show archdebug set|show debug arch
2015 set|show eventdebug set|show debug event
2018 * New BSD user-level threads support
2020 It is now possible to debug programs using the user-level threads
2021 library on OpenBSD and FreeBSD. Currently supported (target)
2024 FreeBSD/amd64 x86_64-*-freebsd*
2025 FreeBSD/i386 i386-*-freebsd*
2026 OpenBSD/i386 i386-*-openbsd*
2028 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2029 are not yet supported.
2031 * New support for Matsushita MN10300 w/sim added
2032 (Work in progress). mn10300-elf.
2034 * REMOVED configurations and files
2036 VxWorks and the XDR protocol *-*-vxworks
2037 Motorola MCORE mcore-*-*
2038 National Semiconductor NS32000 ns32k-*-*
2040 * New "set print array-indexes" command
2042 After turning this setting "on", GDB prints the index of each element
2043 when displaying arrays. The default is "off" to preserve the previous
2046 * VAX floating point support
2048 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2050 * User-defined command support
2052 In addition to using $arg0..$arg9 for argument passing, it is now possible
2053 to use $argc to determine now many arguments have been passed. See the
2054 section on user-defined commands in the user manual for more information.
2056 *** Changes in GDB 6.3:
2058 * New command line option
2060 GDB now accepts -l followed by a number to set the timeout for remote
2063 * GDB works with GCC -feliminate-dwarf2-dups
2065 GDB now supports a more compact representation of DWARF-2 debug
2066 information using DW_FORM_ref_addr references. These are produced
2067 by GCC with the option -feliminate-dwarf2-dups and also by some
2068 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2069 to use -feliminate-dwarf2-dups.
2071 * Internationalization
2073 When supported by the host system, GDB will be built with
2074 internationalization (libintl). The task of marking up the sources is
2075 continued, we're looking forward to our first translation.
2079 Initial support for debugging programs compiled with the GNAT
2080 implementation of the Ada programming language has been integrated
2081 into GDB. In this release, support is limited to expression evaluation.
2083 * New native configurations
2085 GNU/Linux/m32r m32r-*-linux-gnu
2089 GDB's remote protocol now includes support for the 'p' packet. This
2090 packet is used to fetch individual registers from a remote inferior.
2092 * END-OF-LIFE registers[] compatibility module
2094 GDB's internal register infrastructure has been completely rewritten.
2095 The new infrastructure making possible the implementation of key new
2096 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2099 GDB 6.3 will be the last release to include the the registers[]
2100 compatibility module that allowed out-of-date configurations to
2101 continue to work. This change directly impacts the following
2111 powerpc bdm protocol
2113 Unless there is activity to revive these configurations, they will be
2114 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2116 * OBSOLETE configurations and files
2118 Configurations that have been declared obsolete in this release have
2119 been commented out. Unless there is activity to revive these
2120 configurations, the next release of GDB will have their sources
2121 permanently REMOVED.
2130 *** Changes in GDB 6.2.1:
2132 * MIPS `break main; run' gave an heuristic-fence-post warning
2134 When attempting to run even a simple program, a warning about
2135 heuristic-fence-post being hit would be reported. This problem has
2138 * MIPS IRIX 'long double' crashed GDB
2140 When examining a long double variable, GDB would get a segmentation
2141 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2142 IRIX long double values).
2146 A bug in the VAX stack code was causing problems with the "next"
2147 command. This problem has been fixed.
2149 *** Changes in GDB 6.2:
2151 * Fix for ``many threads''
2153 On GNU/Linux systems that use the NPTL threads library, a program
2154 rapidly creating and deleting threads would confuse GDB leading to the
2157 ptrace: No such process.
2158 thread_db_get_info: cannot get thread info: generic error
2160 This problem has been fixed.
2162 * "-async" and "-noasync" options removed.
2164 Support for the broken "-noasync" option has been removed (it caused
2167 * New ``start'' command.
2169 This command runs the program until the begining of the main procedure.
2171 * New BSD Kernel Data Access Library (libkvm) interface
2173 Using ``target kvm'' it is now possible to debug kernel core dumps and
2174 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2175 platforms. Currently supported (native-only) configurations are:
2177 FreeBSD/amd64 x86_64-*-freebsd*
2178 FreeBSD/i386 i?86-*-freebsd*
2179 NetBSD/i386 i?86-*-netbsd*
2180 NetBSD/m68k m68*-*-netbsd*
2181 NetBSD/sparc sparc-*-netbsd*
2182 OpenBSD/amd64 x86_64-*-openbsd*
2183 OpenBSD/i386 i?86-*-openbsd*
2184 OpenBSD/m68k m68*-openbsd*
2185 OpenBSD/sparc sparc-*-openbsd*
2187 * Signal trampoline code overhauled
2189 Many generic problems with GDB's signal handling code have been fixed.
2190 These include: backtraces through non-contiguous stacks; recognition
2191 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2192 call; backtrace through a signal trampoline; step into and out of
2193 signal handlers; and single-stepping in the signal trampoline.
2195 Please note that kernel bugs are a limiting factor here. These
2196 features have been shown to work on an s390 GNU/Linux system that
2197 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2199 * Cygwin support for DWARF 2 added.
2201 * New native configurations
2203 GNU/Linux/hppa hppa*-*-linux*
2204 OpenBSD/hppa hppa*-*-openbsd*
2205 OpenBSD/m68k m68*-*-openbsd*
2206 OpenBSD/m88k m88*-*-openbsd*
2207 OpenBSD/powerpc powerpc-*-openbsd*
2208 NetBSD/vax vax-*-netbsd*
2209 OpenBSD/vax vax-*-openbsd*
2211 * END-OF-LIFE frame compatibility module
2213 GDB's internal frame infrastructure has been completely rewritten.
2214 The new infrastructure making it possible to support key new features
2215 including DWARF 2 Call Frame Information. To aid in the task of
2216 migrating old configurations to this new infrastructure, a
2217 compatibility module, that allowed old configurations to continue to
2218 work, was also included.
2220 GDB 6.2 will be the last release to include this frame compatibility
2221 module. This change directly impacts the following configurations:
2231 Unless there is activity to revive these configurations, they will be
2232 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2234 * REMOVED configurations and files
2236 Sun 3, running SunOS 3 m68*-*-sunos3*
2237 Sun 3, running SunOS 4 m68*-*-sunos4*
2238 Sun 2, running SunOS 3 m68000-*-sunos3*
2239 Sun 2, running SunOS 4 m68000-*-sunos4*
2240 Motorola 680x0 running LynxOS m68*-*-lynxos*
2241 AT&T 3b1/Unix pc m68*-att-*
2242 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2243 decstation mips-dec-* mips-little-*
2244 riscos mips-*-riscos* mips-*-sysv*
2245 sonymips mips-sony-*
2246 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2248 *** Changes in GDB 6.1.1:
2250 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2252 The TUI (Text-mode User Interface) is now built as part of a default
2253 GDB configuration. It is enabled by either selecting the TUI with the
2254 command line option "-i=tui" or by running the separate "gdbtui"
2255 program. For more information on the TUI, see the manual "Debugging
2258 * Pending breakpoint support (also included in GDB 6.1)
2260 Support has been added to allow you to specify breakpoints in shared
2261 libraries that have not yet been loaded. If a breakpoint location
2262 cannot be found, and the "breakpoint pending" option is set to auto,
2263 GDB queries you if you wish to make the breakpoint pending on a future
2264 shared-library load. If and when GDB resolves the breakpoint symbol,
2265 the pending breakpoint is removed as one or more regular breakpoints
2268 Pending breakpoints are very useful for GCJ Java debugging.
2270 * Fixed ISO-C build problems
2272 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2273 non ISO-C code that stopped them being built using a more strict ISO-C
2274 compiler (e.g., IBM's C compiler).
2276 * Fixed build problem on IRIX 5
2278 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2279 wasn't able to compile compile on an IRIX 5 system.
2281 * Added execute permission to gdb/gdbserver/configure
2283 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2284 permission. This bug would cause configure to fail on a number of
2285 systems (Solaris, IRIX). Ref: server/519.
2287 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2289 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2290 has been updated to use constant array sizes.
2292 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2294 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2295 its generated DWARF Call Frame Info. This encoding was causing GDB to
2296 panic, that panic has been fixed. Ref: gdb/1628.
2298 * Fixed a problem when examining parameters in shared library code.
2300 When examining parameters in optimized shared library code generated
2301 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2302 not available''. GDB now correctly displays the variable's value.
2304 *** Changes in GDB 6.1:
2306 * Removed --with-mmalloc
2308 Support for the mmalloc memory manager has been removed, as it
2309 conflicted with the internal gdb byte cache.
2311 * Changes in AMD64 configurations
2313 The AMD64 target now includes the %cs and %ss registers. As a result
2314 the AMD64 remote protocol has changed; this affects the floating-point
2315 and SSE registers. If you rely on those registers for your debugging,
2316 you should upgrade gdbserver on the remote side.
2318 * Revised SPARC target
2320 The SPARC target has been completely revised, incorporating the
2321 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2322 support for LynxOS and SunOS 4 has been dropped. Calling functions
2323 from within GDB on operating systems with a non-executable stack
2324 (Solaris, OpenBSD) now works.
2328 GDB has a new C++ demangler which does a better job on the mangled
2329 names generated by current versions of g++. It also runs faster, so
2330 with this and other changes gdb should now start faster on large C++
2333 * DWARF 2 Location Expressions
2335 GDB support for location expressions has been extended to support function
2336 arguments and frame bases. Older versions of GDB could crash when they
2339 * C++ nested types and namespaces
2341 GDB's support for nested types and namespaces in C++ has been
2342 improved, especially if you use the DWARF 2 debugging format. (This
2343 is the default for recent versions of GCC on most platforms.)
2344 Specifically, if you have a class "Inner" defined within a class or
2345 namespace "Outer", then GDB realizes that the class's name is
2346 "Outer::Inner", not simply "Inner". This should greatly reduce the
2347 frequency of complaints about not finding RTTI symbols. In addition,
2348 if you are stopped at inside of a function defined within a namespace,
2349 GDB modifies its name lookup accordingly.
2351 * New native configurations
2353 NetBSD/amd64 x86_64-*-netbsd*
2354 OpenBSD/amd64 x86_64-*-openbsd*
2355 OpenBSD/alpha alpha*-*-openbsd*
2356 OpenBSD/sparc sparc-*-openbsd*
2357 OpenBSD/sparc64 sparc64-*-openbsd*
2359 * New debugging protocols
2361 M32R with SDI protocol m32r-*-elf*
2363 * "set prompt-escape-char" command deleted.
2365 The command "set prompt-escape-char" has been deleted. This command,
2366 and its very obscure effet on GDB's prompt, was never documented,
2367 tested, nor mentioned in the NEWS file.
2369 * OBSOLETE configurations and files
2371 Configurations that have been declared obsolete in this release have
2372 been commented out. Unless there is activity to revive these
2373 configurations, the next release of GDB will have their sources
2374 permanently REMOVED.
2376 Sun 3, running SunOS 3 m68*-*-sunos3*
2377 Sun 3, running SunOS 4 m68*-*-sunos4*
2378 Sun 2, running SunOS 3 m68000-*-sunos3*
2379 Sun 2, running SunOS 4 m68000-*-sunos4*
2380 Motorola 680x0 running LynxOS m68*-*-lynxos*
2381 AT&T 3b1/Unix pc m68*-att-*
2382 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2383 decstation mips-dec-* mips-little-*
2384 riscos mips-*-riscos* mips-*-sysv*
2385 sonymips mips-sony-*
2386 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2388 * REMOVED configurations and files
2390 SGI Irix-4.x mips-sgi-irix4 or iris4
2391 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2392 Z8000 simulator z8k-zilog-none or z8ksim
2393 Matsushita MN10200 w/simulator mn10200-*-*
2394 H8/500 simulator h8500-hitachi-hms or h8500hms
2395 HP/PA running BSD hppa*-*-bsd*
2396 HP/PA running OSF/1 hppa*-*-osf*
2397 HP/PA Pro target hppa*-*-pro*
2398 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2399 386BSD i[3456]86-*-bsd*
2400 Sequent family i[3456]86-sequent-sysv4*
2401 i[3456]86-sequent-sysv*
2402 i[3456]86-sequent-bsd*
2403 SPARC running LynxOS sparc-*-lynxos*
2404 SPARC running SunOS 4 sparc-*-sunos4*
2405 Tsqware Sparclet sparclet-*-*
2406 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2408 *** Changes in GDB 6.0:
2412 Support for debugging the Objective-C programming language has been
2413 integrated into GDB.
2415 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2417 DWARF 2's Call Frame Information makes available compiler generated
2418 information that more exactly describes the program's run-time stack.
2419 By using this information, GDB is able to provide more robust stack
2422 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2423 have been updated to use a new backtrace mechanism which includes
2424 DWARF 2 CFI support.
2428 GDB's remote protocol has been extended to include support for hosted
2429 file I/O (where the remote target uses GDB's file system). See GDB's
2430 remote protocol documentation for details.
2432 * All targets using the new architecture framework.
2434 All of GDB's targets have been updated to use the new internal
2435 architecture framework. The way is now open for future GDB releases
2436 to include cross-architecture native debugging support (i386 on amd64,
2439 * GNU/Linux's Thread Local Storage (TLS)
2441 GDB now includes support for for the GNU/Linux implementation of
2442 per-thread variables.
2444 * GNU/Linux's Native POSIX Thread Library (NPTL)
2446 GDB's thread code has been updated to work with either the new
2447 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2449 * Separate debug info.
2451 GDB, in conjunction with BINUTILS, now supports a mechanism for
2452 automatically loading debug information from a separate file. Instead
2453 of shipping full debug and non-debug versions of system libraries,
2454 system integrators can now instead ship just the stripped libraries
2455 and optional debug files.
2457 * DWARF 2 Location Expressions
2459 DWARF 2 Location Expressions allow the compiler to more completely
2460 describe the location of variables (even in optimized code) to the
2463 GDB now includes preliminary support for location expressions (support
2464 for DW_OP_piece is still missing).
2468 A number of long standing bugs that caused GDB to die while starting a
2469 Java application have been fixed. GDB's Java support is now
2470 considered "useable".
2472 * GNU/Linux support for fork, vfork, and exec.
2474 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2475 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2478 * GDB supports logging output to a file
2480 There are two new commands, "set logging" and "show logging", which can be
2481 used to capture GDB's output to a file.
2483 * The meaning of "detach" has changed for gdbserver
2485 The "detach" command will now resume the application, as documented. To
2486 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2489 * d10v, m68hc11 `regs' command deprecated
2491 The `info registers' command has been updated so that it displays the
2492 registers using a format identical to the old `regs' command.
2496 A new command, "maint set profile on/off", has been added. This command can
2497 be used to enable or disable profiling while running GDB, to profile a
2498 session or a set of commands. In addition there is a new configure switch,
2499 "--enable-profiling", which will cause GDB to be compiled with profiling
2500 data, for more informative profiling results.
2502 * Default MI syntax changed to "mi2".
2504 The default MI (machine interface) syntax, enabled by the command line
2505 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2506 "mi1", can be enabled by specifying the option "-i=mi1".
2508 Support for the original "mi0" syntax (included in GDB 5.0) has been
2511 Fix for gdb/192: removed extraneous space when displaying frame level.
2512 Fix for gdb/672: update changelist is now output in mi list format.
2513 Fix for gdb/702: a -var-assign that updates the value now shows up
2514 in a subsequent -var-update.
2516 * New native configurations.
2518 FreeBSD/amd64 x86_64-*-freebsd*
2520 * Multi-arched targets.
2522 HP/PA HPUX11 hppa*-*-hpux*
2523 Renesas M32R/D w/simulator m32r-*-elf*
2525 * OBSOLETE configurations and files
2527 Configurations that have been declared obsolete in this release have
2528 been commented out. Unless there is activity to revive these
2529 configurations, the next release of GDB will have their sources
2530 permanently REMOVED.
2532 Z8000 simulator z8k-zilog-none or z8ksim
2533 Matsushita MN10200 w/simulator mn10200-*-*
2534 H8/500 simulator h8500-hitachi-hms or h8500hms
2535 HP/PA running BSD hppa*-*-bsd*
2536 HP/PA running OSF/1 hppa*-*-osf*
2537 HP/PA Pro target hppa*-*-pro*
2538 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2539 Sequent family i[3456]86-sequent-sysv4*
2540 i[3456]86-sequent-sysv*
2541 i[3456]86-sequent-bsd*
2542 Tsqware Sparclet sparclet-*-*
2543 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2545 * REMOVED configurations and files
2548 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2549 IBM AIX PS/2 i[3456]86-*-aix
2550 i386 running Mach 3.0 i[3456]86-*-mach3*
2551 i386 running Mach i[3456]86-*-mach*
2552 i386 running OSF/1 i[3456]86-*osf1mk*
2553 HP/Apollo 68k Family m68*-apollo*-sysv*,
2555 m68*-hp-bsd*, m68*-hp-hpux*
2556 Argonaut Risc Chip (ARC) arc-*-*
2557 Mitsubishi D30V d30v-*-*
2558 Fujitsu FR30 fr30-*-elf*
2559 OS/9000 i[34]86-*-os9k
2560 I960 with MON960 i960-*-coff
2562 * MIPS $fp behavior changed
2564 The convenience variable $fp, for the MIPS, now consistently returns
2565 the address of the current frame's base. Previously, depending on the
2566 context, $fp could refer to either $sp or the current frame's base
2567 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2568 The GNU Source-Level Debugger''.
2570 *** Changes in GDB 5.3:
2572 * GNU/Linux shared library multi-threaded performance improved.
2574 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2575 `/proc', in preference to `ptrace' for memory reads. This may result
2576 in an improvement in the start-up time of multi-threaded, shared
2577 library applications when run under GDB. One GDB user writes: ``loads
2578 shared libs like mad''.
2580 * ``gdbserver'' now supports multi-threaded applications on some targets
2582 Support for debugging multi-threaded applications which use
2583 the GNU/Linux LinuxThreads package has been added for
2584 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2585 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2587 * GDB now supports C/C++ preprocessor macros.
2589 GDB now expands preprocessor macro invocations in C/C++ expressions,
2590 and provides various commands for showing macro definitions and how
2593 The new command `macro expand EXPRESSION' expands any macro
2594 invocations in expression, and shows the result.
2596 The new command `show macro MACRO-NAME' shows the definition of the
2597 macro named MACRO-NAME, and where it was defined.
2599 Most compilers don't include information about macros in the debugging
2600 information by default. In GCC 3.1, for example, you need to compile
2601 your program with the options `-gdwarf-2 -g3'. If the macro
2602 information is present in the executable, GDB will read it.
2604 * Multi-arched targets.
2606 DEC Alpha (partial) alpha*-*-*
2607 DEC VAX (partial) vax-*-*
2609 National Semiconductor NS32000 (partial) ns32k-*-*
2610 Motorola 68000 (partial) m68k-*-*
2611 Motorola MCORE mcore-*-*
2615 Fujitsu FRV architecture added by Red Hat frv*-*-*
2618 * New native configurations
2620 Alpha NetBSD alpha*-*-netbsd*
2621 SH NetBSD sh*-*-netbsdelf*
2622 MIPS NetBSD mips*-*-netbsd*
2623 UltraSPARC NetBSD sparc64-*-netbsd*
2625 * OBSOLETE configurations and files
2627 Configurations that have been declared obsolete in this release have
2628 been commented out. Unless there is activity to revive these
2629 configurations, the next release of GDB will have their sources
2630 permanently REMOVED.
2632 Mitsubishi D30V d30v-*-*
2633 OS/9000 i[34]86-*-os9k
2634 IBM AIX PS/2 i[3456]86-*-aix
2635 Fujitsu FR30 fr30-*-elf*
2636 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2637 Argonaut Risc Chip (ARC) arc-*-*
2638 i386 running Mach 3.0 i[3456]86-*-mach3*
2639 i386 running Mach i[3456]86-*-mach*
2640 i386 running OSF/1 i[3456]86-*osf1mk*
2641 HP/Apollo 68k Family m68*-apollo*-sysv*,
2643 m68*-hp-bsd*, m68*-hp-hpux*
2644 I960 with MON960 i960-*-coff
2646 * OBSOLETE languages
2648 CHILL, a Pascal like language used by telecommunications companies.
2650 * REMOVED configurations and files
2652 AMD 29k family via UDI a29k-amd-udi, udi29k
2653 A29K VxWorks a29k-*-vxworks
2654 AMD 29000 embedded, using EBMON a29k-none-none
2655 AMD 29000 embedded with COFF a29k-none-coff
2656 AMD 29000 embedded with a.out a29k-none-aout
2658 testsuite/gdb.hp/gdb.threads-hp/ directory
2660 * New command "set max-user-call-depth <nnn>"
2662 This command allows the user to limit the call depth of user-defined
2663 commands. The default is 1024.
2665 * Changes in FreeBSD/i386 native debugging.
2667 Support for the "generate-core-file" has been added.
2669 * New commands "dump", "append", and "restore".
2671 These commands allow data to be copied from target memory
2672 to a bfd-format or binary file (dump and append), and back
2673 from a file into memory (restore).
2675 * Improved "next/step" support on multi-processor Alpha Tru64.
2677 The previous single-step mechanism could cause unpredictable problems,
2678 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2679 of a software single-step mechanism prevents this.
2681 *** Changes in GDB 5.2.1:
2689 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2690 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2691 Fix, by Joel Brobecker imported from mainline.
2693 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2694 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2695 Fix, by Fred Fish, imported from mainline.
2697 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2698 Surprisingly enough, it works now.
2699 By Michal Ludvig, imported from mainline.
2701 i386 hardware watchpoint support:
2702 avoid misses on second run for some targets.
2703 By Pierre Muller, imported from mainline.
2705 *** Changes in GDB 5.2:
2707 * New command "set trust-readonly-sections on[off]".
2709 This command is a hint that tells gdb that read-only sections
2710 really are read-only (ie. that their contents will not change).
2711 In this mode, gdb will go to the object file rather than the
2712 target to read memory from read-only sections (such as ".text").
2713 This can be a significant performance improvement on some
2714 (notably embedded) targets.
2716 * New command "generate-core-file" (or "gcore").
2718 This new gdb command allows the user to drop a core file of the child
2719 process state at any time. So far it's been implemented only for
2720 GNU/Linux and Solaris, but should be relatively easily ported to other
2721 hosts. Argument is core file name (defaults to core.<pid>).
2723 * New command line option
2725 GDB now accepts --pid or -p followed by a process id.
2727 * Change in command line behavior -- corefiles vs. process ids.
2729 There is a subtle behavior in the way in which GDB handles
2730 command line arguments. The first non-flag argument is always
2731 a program to debug, but the second non-flag argument may either
2732 be a corefile or a process id. Previously, GDB would attempt to
2733 open the second argument as a corefile, and if that failed, would
2734 issue a superfluous error message and then attempt to attach it as
2735 a process. Now, if the second argument begins with a non-digit,
2736 it will be treated as a corefile. If it begins with a digit,
2737 GDB will attempt to attach it as a process, and if no such process
2738 is found, will then attempt to open it as a corefile.
2740 * Changes in ARM configurations.
2742 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2743 configuration is fully multi-arch.
2745 * New native configurations
2747 ARM NetBSD arm*-*-netbsd*
2748 x86 OpenBSD i[3456]86-*-openbsd*
2749 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2750 Sparc64 running FreeBSD sparc64-*-freebsd*
2754 Sanyo XStormy16 xstormy16-elf
2756 * OBSOLETE configurations and files
2758 Configurations that have been declared obsolete in this release have
2759 been commented out. Unless there is activity to revive these
2760 configurations, the next release of GDB will have their sources
2761 permanently REMOVED.
2763 AMD 29k family via UDI a29k-amd-udi, udi29k
2764 A29K VxWorks a29k-*-vxworks
2765 AMD 29000 embedded, using EBMON a29k-none-none
2766 AMD 29000 embedded with COFF a29k-none-coff
2767 AMD 29000 embedded with a.out a29k-none-aout
2769 testsuite/gdb.hp/gdb.threads-hp/ directory
2771 * REMOVED configurations and files
2773 TI TMS320C80 tic80-*-*
2775 PowerPC Solaris powerpcle-*-solaris*
2776 PowerPC Windows NT powerpcle-*-cygwin32
2777 PowerPC Netware powerpc-*-netware*
2778 Harris/CXUX m88k m88*-harris-cxux*
2779 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2780 ns32k-utek-sysv* ns32k-utek-*
2781 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2782 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2783 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2784 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2785 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2787 * Changes to command line processing
2789 The new `--args' feature can be used to specify command-line arguments
2790 for the inferior from gdb's command line.
2792 * Changes to key bindings
2794 There is a new `operate-and-get-next' function bound to `C-o'.
2796 *** Changes in GDB 5.1.1
2798 Fix compile problem on DJGPP.
2800 Fix a problem with floating-point registers on the i386 being
2803 Fix to stop GDB crashing on .debug_str debug info.
2805 Numerous documentation fixes.
2807 Numerous testsuite fixes.
2809 *** Changes in GDB 5.1:
2811 * New native configurations
2813 Alpha FreeBSD alpha*-*-freebsd*
2814 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2815 MIPS GNU/Linux mips*-*-linux*
2816 MIPS SGI Irix 6.x mips*-sgi-irix6*
2817 ia64 AIX ia64-*-aix*
2818 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2822 Motorola 68HC11 and 68HC12 m68hc11-elf
2824 UltraSparc running GNU/Linux sparc64-*-linux*
2826 * OBSOLETE configurations and files
2828 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2829 Harris/CXUX m88k m88*-harris-cxux*
2830 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2831 ns32k-utek-sysv* ns32k-utek-*
2832 TI TMS320C80 tic80-*-*
2834 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2835 PowerPC Solaris powerpcle-*-solaris*
2836 PowerPC Windows NT powerpcle-*-cygwin32
2837 PowerPC Netware powerpc-*-netware*
2838 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2839 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2840 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2841 Apple Macintosh (MPW) host N/A
2843 stuff.c (Program to stuff files into a specially prepared space in kdb)
2844 kdb-start.c (Main loop for the standalone kernel debugger)
2846 Configurations that have been declared obsolete in this release have
2847 been commented out. Unless there is activity to revive these
2848 configurations, the next release of GDB will have their sources
2849 permanently REMOVED.
2851 * REMOVED configurations and files
2853 Altos 3068 m68*-altos-*
2854 Convex c1-*-*, c2-*-*
2856 ARM RISCix arm-*-* (as host)
2860 * GDB has been converted to ISO C.
2862 GDB's source code has been converted to ISO C. In particular, the
2863 sources are fully protoized, and rely on standard headers being
2868 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2870 * The MI enabled by default.
2872 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2873 revised and enabled by default. Packages which use GDB as a debugging
2874 engine behind a UI or another front end are encouraged to switch to
2875 using the GDB/MI interface, instead of the old annotations interface
2876 which is now deprecated.
2878 * Support for debugging Pascal programs.
2880 GDB now includes support for debugging Pascal programs. The following
2881 main features are supported:
2883 - Pascal-specific data types such as sets;
2885 - automatic recognition of Pascal sources based on file-name
2888 - Pascal-style display of data types, variables, and functions;
2890 - a Pascal expression parser.
2892 However, some important features are not yet supported.
2894 - Pascal string operations are not supported at all;
2896 - there are some problems with boolean types;
2898 - Pascal type hexadecimal constants are not supported
2899 because they conflict with the internal variables format;
2901 - support for Pascal objects and classes is not full yet;
2903 - unlike Pascal, GDB is case-sensitive for symbol names.
2905 * Changes in completion.
2907 Commands such as `shell', `run' and `set args', which pass arguments
2908 to inferior programs, now complete on file names, similar to what
2909 users expect at the shell prompt.
2911 Commands which accept locations, such as `disassemble', `print',
2912 `breakpoint', `until', etc. now complete on filenames as well as
2913 program symbols. Thus, if you type "break foob TAB", and the source
2914 files linked into the programs include `foobar.c', that file name will
2915 be one of the candidates for completion. However, file names are not
2916 considered for completion after you typed a colon that delimits a file
2917 name from a name of a function in that file, as in "break foo.c:bar".
2919 `set demangle-style' completes on available demangling styles.
2921 * New platform-independent commands:
2923 It is now possible to define a post-hook for a command as well as a
2924 hook that runs before the command. For more details, see the
2925 documentation of `hookpost' in the GDB manual.
2927 * Changes in GNU/Linux native debugging.
2929 Support for debugging multi-threaded programs has been completely
2930 revised for all platforms except m68k and sparc. You can now debug as
2931 many threads as your system allows you to have.
2933 Attach/detach is supported for multi-threaded programs.
2935 Support for SSE registers was added for x86. This doesn't work for
2936 multi-threaded programs though.
2938 * Changes in MIPS configurations.
2940 Multi-arch support is enabled for all MIPS configurations.
2942 GDB can now be built as native debugger on SGI Irix 6.x systems for
2943 debugging n32 executables. (Debugging 64-bit executables is not yet
2946 * Unified support for hardware watchpoints in all x86 configurations.
2948 Most (if not all) native x86 configurations support hardware-assisted
2949 breakpoints and watchpoints in a unified manner. This support
2950 implements debug register sharing between watchpoints, which allows to
2951 put a virtually infinite number of watchpoints on the same address,
2952 and also supports watching regions up to 16 bytes with several debug
2955 The new maintenance command `maintenance show-debug-regs' toggles
2956 debugging print-outs in functions that insert, remove, and test
2957 watchpoints and hardware breakpoints.
2959 * Changes in the DJGPP native configuration.
2961 New command ``info dos sysinfo'' displays assorted information about
2962 the CPU, OS, memory, and DPMI server.
2964 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2965 display information about segment descriptors stored in GDT, LDT, and
2968 New commands ``info dos pde'' and ``info dos pte'' display entries
2969 from Page Directory and Page Tables (for now works with CWSDPMI only).
2970 New command ``info dos address-pte'' displays the Page Table entry for
2971 a given linear address.
2973 GDB can now pass command lines longer than 126 characters to the
2974 program being debugged (requires an update to the libdbg.a library
2975 which is part of the DJGPP development kit).
2977 DWARF2 debug info is now supported.
2979 It is now possible to `step' and `next' through calls to `longjmp'.
2981 * Changes in documentation.
2983 All GDB documentation was converted to GFDL, the GNU Free
2984 Documentation License.
2986 Tracepoints-related commands are now fully documented in the GDB
2989 TUI, the Text-mode User Interface, is now documented in the manual.
2991 Tracepoints-related commands are now fully documented in the GDB
2994 The "GDB Internals" manual now has an index. It also includes
2995 documentation of `ui_out' functions, GDB coding standards, x86
2996 hardware watchpoints, and memory region attributes.
2998 * GDB's version number moved to ``version.in''
3000 The Makefile variable VERSION has been replaced by the file
3001 ``version.in''. People creating GDB distributions should update the
3002 contents of this file.
3006 GUD support is now a standard part of the EMACS distribution.
3008 *** Changes in GDB 5.0:
3010 * Improved support for debugging FP programs on x86 targets
3012 Unified and much-improved support for debugging floating-point
3013 programs on all x86 targets. In particular, ``info float'' now
3014 displays the FP registers in the same format on all x86 targets, with
3015 greater level of detail.
3017 * Improvements and bugfixes in hardware-assisted watchpoints
3019 It is now possible to watch array elements, struct members, and
3020 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3021 on x86 targets no longer erroneously trigger when the address is
3024 * Improvements in the native DJGPP version of GDB
3026 The distribution now includes all the scripts and auxiliary files
3027 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3028 machines ``out of the box''.
3030 The DJGPP version can now debug programs that use signals. It is
3031 possible to catch signals that happened in the debuggee, deliver
3032 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3033 would kill the program being debugged.) Programs that hook hardware
3034 interrupts (keyboard, timer, etc.) can also be debugged.
3036 It is now possible to debug DJGPP programs that redirect their
3037 standard handles or switch them to raw (as opposed to cooked) mode, or
3038 even close them. The command ``run < foo > bar'' works as expected,
3039 and ``info terminal'' reports useful information about the debuggee's
3040 terminal, including raw/cooked mode, redirection, etc.
3042 The DJGPP version now uses termios functions for console I/O, which
3043 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3046 DOS-style file names with drive letters are now fully supported by
3049 It is now possible to debug DJGPP programs that switch their working
3050 directory. It is also possible to rerun the debuggee any number of
3051 times without restarting GDB; thus, you can use the same setup,
3052 breakpoints, etc. for many debugging sessions.
3054 * New native configurations
3056 ARM GNU/Linux arm*-*-linux*
3057 PowerPC GNU/Linux powerpc-*-linux*
3061 Motorola MCore mcore-*-*
3062 x86 VxWorks i[3456]86-*-vxworks*
3063 PowerPC VxWorks powerpc-*-vxworks*
3064 TI TMS320C80 tic80-*-*
3066 * OBSOLETE configurations
3068 Altos 3068 m68*-altos-*
3069 Convex c1-*-*, c2-*-*
3071 ARM RISCix arm-*-* (as host)
3074 Configurations that have been declared obsolete will be commented out,
3075 but the code will be left in place. If there is no activity to revive
3076 these configurations before the next release of GDB, the sources will
3077 be permanently REMOVED.
3079 * Gould support removed
3081 Support for the Gould PowerNode and NP1 has been removed.
3083 * New features for SVR4
3085 On SVR4 native platforms (such as Solaris), if you attach to a process
3086 without first loading a symbol file, GDB will now attempt to locate and
3087 load symbols from the running process's executable file.
3089 * Many C++ enhancements
3091 C++ support has been greatly improved. Overload resolution now works properly
3092 in almost all cases. RTTI support is on the way.
3094 * Remote targets can connect to a sub-program
3096 A popen(3) style serial-device has been added. This device starts a
3097 sub-process (such as a stand-alone simulator) and then communicates
3098 with that. The sub-program to run is specified using the syntax
3099 ``|<program> <args>'' vis:
3101 (gdb) set remotedebug 1
3102 (gdb) target extended-remote |mn10300-elf-sim program-args
3104 * MIPS 64 remote protocol
3106 A long standing bug in the mips64 remote protocol where by GDB
3107 expected certain 32 bit registers (ex SR) to be transfered as 32
3108 instead of 64 bits has been fixed.
3110 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3111 added to provide backward compatibility with older versions of GDB.
3113 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3115 The command ``set remotebinarydownload'' command has been replaced by
3116 ``set remote X-packet''. Other commands in ``set remote'' family
3117 include ``set remote P-packet''.
3119 * Breakpoint commands accept ranges.
3121 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3122 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3123 ``tracepoint passcount'' also accepts a range of tracepoints.
3125 * ``apropos'' command added.
3127 The ``apropos'' command searches through command names and
3128 documentation strings, printing out matches, making it much easier to
3129 try to find a command that does what you are looking for.
3133 A new machine oriented interface (MI) has been added to GDB. This
3134 interface is designed for debug environments running GDB as a separate
3135 process. This is part of the long term libGDB project. See the
3136 "GDB/MI" chapter of the GDB manual for further information. It can be
3137 enabled by configuring with:
3139 .../configure --enable-gdbmi
3141 *** Changes in GDB-4.18:
3143 * New native configurations
3145 HP-UX 10.20 hppa*-*-hpux10.20
3146 HP-UX 11.x hppa*-*-hpux11.0*
3147 M68K GNU/Linux m68*-*-linux*
3151 Fujitsu FR30 fr30-*-elf*
3152 Intel StrongARM strongarm-*-*
3153 Mitsubishi D30V d30v-*-*
3155 * OBSOLETE configurations
3157 Gould PowerNode, NP1 np1-*-*, pn-*-*
3159 Configurations that have been declared obsolete will be commented out,
3160 but the code will be left in place. If there is no activity to revive
3161 these configurations before the next release of GDB, the sources will
3162 be permanently REMOVED.
3166 As a compatibility experiment, GDB's source files buildsym.h and
3167 buildsym.c have been converted to pure standard C, no longer
3168 containing any K&R compatibility code. We believe that all systems in
3169 use today either come with a standard C compiler, or have a GCC port
3170 available. If this is not true, please report the affected
3171 configuration to bug-gdb@gnu.org immediately. See the README file for
3172 information about getting a standard C compiler if you don't have one
3177 GDB now uses readline 2.2.
3179 * set extension-language
3181 You can now control the mapping between filename extensions and source
3182 languages by using the `set extension-language' command. For instance,
3183 you can ask GDB to treat .c files as C++ by saying
3184 set extension-language .c c++
3185 The command `info extensions' lists all of the recognized extensions
3186 and their associated languages.
3188 * Setting processor type for PowerPC and RS/6000
3190 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3191 you can use the `set processor' command to specify what variant of the
3192 PowerPC family you are debugging. The command
3196 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3197 following PowerPC and RS6000 variants:
3199 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3200 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3202 403GC IBM PowerPC 403GC
3203 505 Motorola PowerPC 505
3204 860 Motorola PowerPC 860 or 850
3205 601 Motorola PowerPC 601
3206 602 Motorola PowerPC 602
3207 603 Motorola/IBM PowerPC 603 or 603e
3208 604 Motorola PowerPC 604 or 604e
3209 750 Motorola/IBM PowerPC 750 or 750
3211 At the moment, this command just tells GDB what to name the
3212 special-purpose processor registers. Since almost all the affected
3213 registers are inaccessible to user-level programs, this command is
3214 only useful for remote debugging in its present form.
3218 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3219 more extensive support for HP-UX. Added features include shared
3220 library support, kernel threads and hardware watchpoints for 11.00,
3221 support for HP's ANSI C and C++ compilers, and a compatibility mode
3222 for xdb and dbx commands.
3226 HP's donation includes the new concept of catchpoints, which is a
3227 generalization of the old catch command. On HP-UX, it is now possible
3228 to catch exec, fork, and vfork, as well as library loading.
3230 This means that the existing catch command has changed; its first
3231 argument now specifies the type of catch to be set up. See the
3232 output of "help catch" for a list of catchpoint types.
3234 * Debugging across forks
3236 On HP-UX, you can choose which process to debug when a fork() happens
3241 HP has donated a curses-based terminal user interface (TUI). To get
3242 it, build with --enable-tui. Although this can be enabled for any
3243 configuration, at present it only works for native HP debugging.
3245 * GDB remote protocol additions
3247 A new protocol packet 'X' that writes binary data is now available.
3248 Default behavior is to try 'X', then drop back to 'M' if the stub
3249 fails to respond. The settable variable `remotebinarydownload'
3250 allows explicit control over the use of 'X'.
3252 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3253 full 64-bit address. The command
3255 set remoteaddresssize 32
3257 can be used to revert to the old behaviour. For existing remote stubs
3258 the change should not be noticed, as the additional address information
3261 In order to assist in debugging stubs, you may use the maintenance
3262 command `packet' to send any text string to the stub. For instance,
3264 maint packet heythere
3266 sends the packet "$heythere#<checksum>". Note that it is very easy to
3267 disrupt a debugging session by sending the wrong packet at the wrong
3270 The compare-sections command allows you to compare section data on the
3271 target to what is in the executable file without uploading or
3272 downloading, by comparing CRC checksums.
3274 * Tracing can collect general expressions
3276 You may now collect general expressions at tracepoints. This requires
3277 further additions to the target-side stub; see tracepoint.c and
3278 doc/agentexpr.texi for further details.
3280 * mask-address variable for Mips
3282 For Mips targets, you may control the zeroing of the upper 32 bits of
3283 a 64-bit address by entering `set mask-address on'. This is mainly
3284 of interest to users of embedded R4xxx and R5xxx processors.
3286 * Higher serial baud rates
3288 GDB's serial code now allows you to specify baud rates 57600, 115200,
3289 230400, and 460800 baud. (Note that your host system may not be able
3290 to achieve all of these rates.)
3294 The i960 configuration now includes an initial implementation of a
3295 builtin simulator, contributed by Jim Wilson.
3298 *** Changes in GDB-4.17:
3300 * New native configurations
3302 Alpha GNU/Linux alpha*-*-linux*
3303 Unixware 2.x i[3456]86-unixware2*
3304 Irix 6.x mips*-sgi-irix6*
3305 PowerPC GNU/Linux powerpc-*-linux*
3306 PowerPC Solaris powerpcle-*-solaris*
3307 Sparc GNU/Linux sparc-*-linux*
3308 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3312 Argonaut Risc Chip (ARC) arc-*-*
3313 Hitachi H8/300S h8300*-*-*
3314 Matsushita MN10200 w/simulator mn10200-*-*
3315 Matsushita MN10300 w/simulator mn10300-*-*
3316 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3317 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3318 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3319 Mitsubishi D10V w/simulator d10v-*-*
3320 Mitsubishi M32R/D w/simulator m32r-*-elf*
3321 Tsqware Sparclet sparclet-*-*
3322 NEC V850 w/simulator v850-*-*
3324 * New debugging protocols
3326 ARM with RDI protocol arm*-*-*
3327 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3328 DDB and LSI variants of PMON protocol mips*-*-*
3329 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3330 PowerPC with SDS protocol powerpc{,le}-*-eabi
3331 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3335 All configurations can now understand and use the DWARF 2 debugging
3336 format. The choice is automatic, if the symbol file contains DWARF 2
3341 GDB now includes basic Java language support. This support is
3342 only useful with Java compilers that produce native machine code.
3344 * solib-absolute-prefix and solib-search-path
3346 For SunOS and SVR4 shared libraries, you may now set the prefix for
3347 loading absolute shared library symbol files, and the search path for
3348 locating non-absolute shared library symbol files.
3350 * Live range splitting
3352 GDB can now effectively debug code for which GCC has performed live
3353 range splitting as part of its optimization. See gdb/doc/LRS for
3354 more details on the expected format of the stabs information.
3358 GDB's support for the GNU Hurd, including thread debugging, has been
3359 updated to work with current versions of the Hurd.
3363 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3364 instruction set. ARM GDB automatically detects when Thumb
3365 instructions are in use, and adjusts disassembly and backtracing
3370 GDB's MIPS target configurations now handle the MIP16 16-bit
3375 GDB now includes support for overlays; if an executable has been
3376 linked such that multiple sections are based at the same address, GDB
3377 will decide which section to use for symbolic info. You can choose to
3378 control the decision manually, using overlay commands, or implement
3379 additional target-side support and use "overlay load-target" to bring
3380 in the overlay mapping. Do "help overlay" for more detail.
3384 The command "info symbol <address>" displays information about
3385 the symbol at the specified address.
3389 The standard remote protocol now includes an extension that allows
3390 asynchronous collection and display of trace data. This requires
3391 extensive support in the target-side debugging stub. Tracing mode
3392 includes a new interaction mode in GDB and new commands: see the
3393 file tracepoint.c for more details.
3397 Configurations for embedded MIPS now include a simulator contributed
3398 by Cygnus Solutions. The simulator supports the instruction sets
3399 of most MIPS variants.
3403 Sparc configurations may now include the ERC32 simulator contributed
3404 by the European Space Agency. The simulator is not built into
3405 Sparc targets by default; configure with --enable-sim to include it.
3409 For target configurations that may include multiple variants of a
3410 basic architecture (such as MIPS and SH), you may now set the
3411 architecture explicitly. "set arch" sets, "info arch" lists
3412 the possible architectures.
3414 *** Changes in GDB-4.16:
3416 * New native configurations
3418 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3419 M68K NetBSD m68k-*-netbsd*
3420 PowerPC AIX 4.x powerpc-*-aix*
3421 PowerPC MacOS powerpc-*-macos*
3422 PowerPC Windows NT powerpcle-*-cygwin32
3423 RS/6000 AIX 4.x rs6000-*-aix4*
3427 ARM with RDP protocol arm-*-*
3428 I960 with MON960 i960-*-coff
3429 MIPS VxWorks mips*-*-vxworks*
3430 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3431 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3433 Matra Sparclet sparclet-*-*
3437 The powerpc-eabi configuration now includes the PSIM simulator,
3438 contributed by Andrew Cagney, with assistance from Mike Meissner.
3439 PSIM is a very elaborate model of the PowerPC, including not only
3440 basic instruction set execution, but also details of execution unit
3441 performance and I/O hardware. See sim/ppc/README for more details.
3445 GDB now works with Solaris 2.5.
3447 * Windows 95/NT native
3449 GDB will now work as a native debugger on Windows 95 and Windows NT.
3450 To build it from source, you must use the "gnu-win32" environment,
3451 which uses a DLL to emulate enough of Unix to run the GNU tools.
3452 Further information, binaries, and sources are available at
3453 ftp.cygnus.com, under pub/gnu-win32.
3455 * dont-repeat command
3457 If a user-defined command includes the command `dont-repeat', then the
3458 command will not be repeated if the user just types return. This is
3459 useful if the command is time-consuming to run, so that accidental
3460 extra keystrokes don't run the same command many times.
3462 * Send break instead of ^C
3464 The standard remote protocol now includes an option to send a break
3465 rather than a ^C to the target in order to interrupt it. By default,
3466 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3468 * Remote protocol timeout
3470 The standard remote protocol includes a new variable `remotetimeout'
3471 that allows you to set the number of seconds before GDB gives up trying
3472 to read from the target. The default value is 2.
3474 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3476 By default GDB will automatically keep track of objects as they are
3477 loaded and unloaded by the dynamic linker. By using the command `set
3478 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3479 when shared library events occur, thus allowing you to set breakpoints
3480 in shared libraries which are explicitly loaded by the inferior.
3482 Note this feature does not work on hpux8. On hpux9 you must link
3483 /usr/lib/end.o into your program. This feature should work
3484 automatically on hpux10.
3486 * Irix 5.x hardware watchpoint support
3488 Irix 5 configurations now support the use of hardware watchpoints.
3490 * Mips protocol "SYN garbage limit"
3492 When debugging a Mips target using the `target mips' protocol, you
3493 may set the number of characters that GDB will ignore by setting
3494 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3495 every character. The default value is 1050.
3497 * Recording and replaying remote debug sessions
3499 If you set `remotelogfile' to the name of a file, gdb will write to it
3500 a recording of a remote debug session. This recording may then be
3501 replayed back to gdb using "gdbreplay". See gdbserver/README for
3502 details. This is useful when you have a problem with GDB while doing
3503 remote debugging; you can make a recording of the session and send it
3504 to someone else, who can then recreate the problem.
3506 * Speedups for remote debugging
3508 GDB includes speedups for downloading and stepping MIPS systems using
3509 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3510 and more efficient S-record downloading.
3512 * Memory use reductions and statistics collection
3514 GDB now uses less memory and reports statistics about memory usage.
3515 Try the `maint print statistics' command, for example.
3517 *** Changes in GDB-4.15:
3519 * Psymtabs for XCOFF
3521 The symbol reader for AIX GDB now uses partial symbol tables. This
3522 can greatly improve startup time, especially for large executables.
3524 * Remote targets use caching
3526 Remote targets now use a data cache to speed up communication with the
3527 remote side. The data cache could lead to incorrect results because
3528 it doesn't know about volatile variables, thus making it impossible to
3529 debug targets which use memory mapped I/O devices. `set remotecache
3530 off' turns the the data cache off.
3532 * Remote targets may have threads
3534 The standard remote protocol now includes support for multiple threads
3535 in the target system, using new protocol commands 'H' and 'T'. See
3536 gdb/remote.c for details.
3540 If GDB is configured with `--enable-netrom', then it will include
3541 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3542 acts as though it is a bank of ROM on the target board, but you can
3543 write into it over the network. GDB's support consists only of
3544 support for fast loading into the emulated ROM; to debug, you must use
3545 another protocol, such as standard remote protocol. The usual
3546 sequence is something like
3548 target nrom <netrom-hostname>
3550 target remote <netrom-hostname>:1235
3554 GDB now includes support for the Apple Macintosh, as a host only. It
3555 may be run as either an MPW tool or as a standalone application, and
3556 it can debug through the serial port. All the usual GDB commands are
3557 available, but to the target command, you must supply "serial" as the
3558 device type instead of "/dev/ttyXX". See mpw-README in the main
3559 directory for more information on how to build. The MPW configuration
3560 scripts */mpw-config.in support only a few targets, and only the
3561 mips-idt-ecoff target has been tested.
3565 GDB configuration now uses autoconf. This is not user-visible,
3566 but does simplify configuration and building.
3570 GDB now supports hpux10.
3572 *** Changes in GDB-4.14:
3574 * New native configurations
3576 x86 FreeBSD i[345]86-*-freebsd
3577 x86 NetBSD i[345]86-*-netbsd
3578 NS32k NetBSD ns32k-*-netbsd
3579 Sparc NetBSD sparc-*-netbsd
3583 A29K VxWorks a29k-*-vxworks
3584 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3585 CPU32 EST-300 emulator m68*-*-est*
3586 PowerPC ELF powerpc-*-elf
3589 * Alpha OSF/1 support for procfs
3591 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3592 possible to attach to running processes. As the mounting of the /proc
3593 filesystem is optional on the Alpha, GDB automatically determines
3594 the availability of /proc during startup. This can lead to problems
3595 if /proc is unmounted after GDB has been started.
3597 * Arguments to user-defined commands
3599 User commands may accept up to 10 arguments separated by whitespace.
3600 Arguments are accessed within the user command via $arg0..$arg9. A
3603 print $arg0 + $arg1 + $arg2
3605 To execute the command use:
3608 Defines the command "adder" which prints the sum of its three arguments.
3609 Note the arguments are text substitutions, so they may reference variables,
3610 use complex expressions, or even perform inferior function calls.
3612 * New `if' and `while' commands
3614 This makes it possible to write more sophisticated user-defined
3615 commands. Both commands take a single argument, which is the
3616 expression to evaluate, and must be followed by the commands to
3617 execute, one per line, if the expression is nonzero, the list being
3618 terminated by the word `end'. The `if' command list may include an
3619 `else' word, which causes the following commands to be executed only
3620 if the expression is zero.
3622 * Fortran source language mode
3624 GDB now includes partial support for Fortran 77. It will recognize
3625 Fortran programs and can evaluate a subset of Fortran expressions, but
3626 variables and functions may not be handled correctly. GDB will work
3627 with G77, but does not yet know much about symbols emitted by other
3630 * Better HPUX support
3632 Most debugging facilities now work on dynamic executables for HPPAs
3633 running hpux9 or later. You can attach to running dynamically linked
3634 processes, but by default the dynamic libraries will be read-only, so
3635 for instance you won't be able to put breakpoints in them. To change
3636 that behavior do the following before running the program:
3642 This will cause the libraries to be mapped private and read-write.
3643 To revert to the normal behavior, do this:
3649 You cannot set breakpoints or examine data in the library until after
3650 the library is loaded if the function/data symbols do not have
3653 GDB can now also read debug symbols produced by the HP C compiler on
3654 HPPAs (sorry, no C++, Fortran or 68k support).
3656 * Target byte order now dynamically selectable
3658 You can choose which byte order to use with a target system, via the
3659 commands "set endian big" and "set endian little", and you can see the
3660 current setting by using "show endian". You can also give the command
3661 "set endian auto", in which case GDB will use the byte order
3662 associated with the executable. Currently, only embedded MIPS
3663 configurations support dynamic selection of target byte order.
3665 * New DOS host serial code
3667 This version uses DPMI interrupts to handle buffered I/O, so you
3668 no longer need to run asynctsr when debugging boards connected to
3671 *** Changes in GDB-4.13:
3673 * New "complete" command
3675 This lists all the possible completions for the rest of the line, if it
3676 were to be given as a command itself. This is intended for use by emacs.
3678 * Trailing space optional in prompt
3680 "set prompt" no longer adds a space for you after the prompt you set. This
3681 allows you to set a prompt which ends in a space or one that does not.
3683 * Breakpoint hit counts
3685 "info break" now displays a count of the number of times the breakpoint
3686 has been hit. This is especially useful in conjunction with "ignore"; you
3687 can ignore a large number of breakpoint hits, look at the breakpoint info
3688 to see how many times the breakpoint was hit, then run again, ignoring one
3689 less than that number, and this will get you quickly to the last hit of
3692 * Ability to stop printing at NULL character
3694 "set print null-stop" will cause GDB to stop printing the characters of
3695 an array when the first NULL is encountered. This is useful when large
3696 arrays actually contain only short strings.
3698 * Shared library breakpoints
3700 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3701 breakpoints in shared libraries before the executable is run.
3703 * Hardware watchpoints
3705 There is a new hardware breakpoint for the watch command for sparclite
3706 targets. See gdb/sparclite/hw_breakpoint.note.
3708 Hardware watchpoints are also now supported under GNU/Linux.
3712 Annotations have been added. These are for use with graphical interfaces,
3713 and are still experimental. Currently only gdba.el uses these.
3715 * Improved Irix 5 support
3717 GDB now works properly with Irix 5.2.
3719 * Improved HPPA support
3721 GDB now works properly with the latest GCC and GAS.
3723 * New native configurations
3725 Sequent PTX4 i[34]86-sequent-ptx4
3726 HPPA running OSF/1 hppa*-*-osf*
3727 Atari TT running SVR4 m68*-*-sysv4*
3728 RS/6000 LynxOS rs6000-*-lynxos*
3732 OS/9000 i[34]86-*-os9k
3733 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3736 * Hitachi SH7000 and E7000-PC ICE support
3738 There is now support for communicating with the Hitachi E7000-PC ICE.
3739 This is available automatically when GDB is configured for the SH.
3743 As usual, a variety of small fixes and improvements, both generic
3744 and configuration-specific. See the ChangeLog for more detail.
3746 *** Changes in GDB-4.12:
3748 * Irix 5 is now supported
3752 GDB-4.12 on the HPPA has a number of changes which make it unable
3753 to debug the output from the currently released versions of GCC and
3754 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3755 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3756 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3759 *** Changes in GDB-4.11:
3761 * User visible changes:
3765 The "set remotedebug" option is now consistent between the mips remote
3766 target, remote targets using the gdb-specific protocol, UDI (AMD's
3767 debug protocol for the 29k) and the 88k bug monitor. It is now an
3768 integer specifying a debug level (normally 0 or 1, but 2 means more
3769 debugging info for the mips target).
3771 * DEC Alpha native support
3773 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3774 debug info, but GDB works fairly well with the DEC compiler and should
3775 work with a future GCC release. See the README file for a few
3776 Alpha-specific notes.
3778 * Preliminary thread implementation
3780 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3782 * LynxOS native and target support for 386
3784 This release has been hosted on LynxOS 2.2, and also can be configured
3785 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3788 * Improvements in C++ mangling/demangling.
3790 This release has much better g++ debugging, specifically in name
3791 mangling/demangling, virtual function calls, print virtual table,
3792 call methods, ...etc.
3794 *** Changes in GDB-4.10:
3796 * User visible changes:
3798 Remote debugging using the GDB-specific (`target remote') protocol now
3799 supports the `load' command. This is only useful if you have some
3800 other way of getting the stub to the target system, and you can put it
3801 somewhere in memory where it won't get clobbered by the download.
3803 Filename completion now works.
3805 When run under emacs mode, the "info line" command now causes the
3806 arrow to point to the line specified. Also, "info line" prints
3807 addresses in symbolic form (as well as hex).
3809 All vxworks based targets now support a user settable option, called
3810 vxworks-timeout. This option represents the number of seconds gdb
3811 should wait for responses to rpc's. You might want to use this if
3812 your vxworks target is, perhaps, a slow software simulator or happens
3813 to be on the far side of a thin network line.
3817 This release contains support for using a DEC alpha as a GDB host for
3818 cross debugging. Native alpha debugging is not supported yet.
3821 *** Changes in GDB-4.9:
3825 This is the first GDB release which is accompanied by a matching testsuite.
3826 The testsuite requires installation of dejagnu, which should be available
3827 via ftp from most sites that carry GNU software.
3831 'Cfront' style demangling has had its name changed to 'ARM' style, to
3832 emphasize that it was written from the specifications in the C++ Annotated
3833 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3834 disclaimers, it still generated too much confusion with users attempting to
3835 use gdb with AT&T cfront.
3839 GDB now uses a standard remote interface to a simulator library.
3840 So far, the library contains simulators for the Zilog Z8001/2, the
3841 Hitachi H8/300, H8/500 and Super-H.
3843 * New targets supported
3845 H8/300 simulator h8300-hitachi-hms or h8300hms
3846 H8/500 simulator h8500-hitachi-hms or h8500hms
3847 SH simulator sh-hitachi-hms or sh
3848 Z8000 simulator z8k-zilog-none or z8ksim
3849 IDT MIPS board over serial line mips-idt-ecoff
3851 Cross-debugging to GO32 targets is supported. It requires a custom
3852 version of the i386-stub.c module which is integrated with the
3853 GO32 memory extender.
3855 * New remote protocols
3857 MIPS remote debugging protocol.
3859 * New source languages supported
3861 This version includes preliminary support for Chill, a Pascal like language
3862 used by telecommunications companies. Chill support is also being integrated
3863 into the GNU compiler, but we don't know when it will be publically available.
3866 *** Changes in GDB-4.8:
3868 * HP Precision Architecture supported
3870 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3871 version of this support was available as a set of patches from the
3872 University of Utah. GDB does not support debugging of programs
3873 compiled with the HP compiler, because HP will not document their file
3874 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3875 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3877 Many problems in the preliminary version have been fixed.
3879 * Faster and better demangling
3881 We have improved template demangling and fixed numerous bugs in the GNU style
3882 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3883 character types (wchar_t) are now supported. Demangling of each symbol is now
3884 only done once, and is cached when the symbol table for a file is read in.
3885 This results in a small increase in memory usage for C programs, a moderate
3886 increase in memory usage for C++ programs, and a fantastic speedup in
3889 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3890 from the specifications in the Annotated Reference Manual, which AT&T's
3891 compiler does not actually implement.
3893 * G++ multiple inheritance compiler problem
3895 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3896 inheritance lattices was reworked to properly discover ambiguities. We
3897 recently found an example which causes this new algorithm to fail in a
3898 very subtle way, producing bad debug information for those classes.
3899 The file 'gcc.patch' (in this directory) can be applied to gcc to
3900 circumvent the problem. A future GCC release will contain a complete
3903 The previous G++ debug info problem (mentioned below for the gdb-4.7
3904 release) is fixed in gcc version 2.3.2.
3906 * Improved configure script
3908 The `configure' script will now attempt to guess your system type if
3909 you don't supply a host system type. The old scheme of supplying a
3910 host system triplet is preferable over using this. All the magic is
3911 done in the new `config.guess' script. Examine it for details.
3913 We have also brought our configure script much more in line with the FSF's
3914 version. It now supports the --with-xxx options. In particular,
3915 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3916 The resulting GDB will not be able to read arbitrary object file formats --
3917 only the format ``expected'' to be used on the configured target system.
3918 We hope to make this the default in a future release.
3920 * Documentation improvements
3922 There's new internal documentation on how to modify GDB, and how to
3923 produce clean changes to the code. We implore people to read it
3924 before submitting changes.
3926 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3927 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3928 `info' files are also provided. To build `info' files from scratch,
3929 you will need the latest `makeinfo' release, which will be available in
3930 a future texinfo-X.Y release.
3932 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3933 We're not sure exactly which versions have this problem, but it has
3934 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3935 or better. If that isn't possible, there is a patch in
3936 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3937 around this problem.
3941 GDB now supports array constants that can be used in expressions typed in by
3942 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3943 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3946 The new directory `gdb/sparclite' contains a program that demonstrates
3947 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3949 * New native hosts supported
3951 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3952 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3954 * New targets supported
3956 AMD 29k family via UDI a29k-amd-udi or udi29k
3958 * New file formats supported
3960 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3961 HPUX core files, and SCO 3.2v2 core files.
3965 Attaching to processes now works again; thanks for the many bug reports.
3967 We have also stomped on a bunch of core dumps caused by
3968 printf_filtered("%s") problems.
3970 We eliminated a copyright problem on the rpc and ptrace header files
3971 for VxWorks, which was discovered at the last minute during the 4.7
3972 release. You should now be able to build a VxWorks GDB.
3974 You can now interrupt gdb while an attached process is running. This
3975 will cause the attached process to stop, and give control back to GDB.
3977 We fixed problems caused by using too many file descriptors
3978 for reading symbols from object files and libraries. This was
3979 especially a problem for programs that used many (~100) shared
3982 The `step' command now only enters a subroutine if there is line number
3983 information for the subroutine. Otherwise it acts like the `next'
3984 command. Previously, `step' would enter subroutines if there was
3985 any debugging information about the routine. This avoids problems
3986 when using `cc -g1' on MIPS machines.
3988 * Internal improvements
3990 GDB's internal interfaces have been improved to make it easier to support
3991 debugging of multiple languages in the future.
3993 GDB now uses a common structure for symbol information internally.
3994 Minimal symbols (derived from linkage symbols in object files), partial
3995 symbols (from a quick scan of debug information), and full symbols
3996 contain a common subset of information, making it easier to write
3997 shared code that handles any of them.
3999 * New command line options
4001 We now accept --silent as an alias for --quiet.
4005 The memory-mapped-malloc library is now licensed under the GNU Library
4006 General Public License.
4008 *** Changes in GDB-4.7:
4010 * Host/native/target split
4012 GDB has had some major internal surgery to untangle the support for
4013 hosts and remote targets. Now, when you configure GDB for a remote
4014 target, it will no longer load in all of the support for debugging
4015 local programs on the host. When fully completed and tested, this will
4016 ensure that arbitrary host/target combinations are possible.
4018 The primary conceptual shift is to separate the non-portable code in
4019 GDB into three categories. Host specific code is required any time GDB
4020 is compiled on that host, regardless of the target. Target specific
4021 code relates to the peculiarities of the target, but can be compiled on
4022 any host. Native specific code is everything else: it can only be
4023 built when the host and target are the same system. Child process
4024 handling and core file support are two common `native' examples.
4026 GDB's use of /proc for controlling Unix child processes is now cleaner.
4027 It has been split out into a single module under the `target_ops' vector,
4028 plus two native-dependent functions for each system that uses /proc.
4030 * New hosts supported
4032 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4033 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4034 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4036 * New targets supported
4038 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4039 68030 and CPU32 m68030-*-*, m68332-*-*
4041 * New native hosts supported
4043 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4044 (386bsd is not well tested yet)
4045 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4047 * New file formats supported
4049 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4050 supports reading of `a.out.adobe' object files, which are an a.out
4051 format extended with minimal information about multiple sections.
4055 `show copying' is the same as the old `info copying'.
4056 `show warranty' is the same as `info warrantee'.
4057 These were renamed for consistency. The old commands continue to work.
4059 `info handle' is a new alias for `info signals'.
4061 You can now define pre-command hooks, which attach arbitrary command
4062 scripts to any command. The commands in the hook will be executed
4063 prior to the user's command. You can also create a hook which will be
4064 executed whenever the program stops. See gdb.texinfo.
4068 We now deal with Cfront style name mangling, and can even extract type
4069 info from mangled symbols. GDB can automatically figure out which
4070 symbol mangling style your C++ compiler uses.
4072 Calling of methods and virtual functions has been improved as well.
4076 The crash that occured when debugging Sun Ansi-C compiled binaries is
4077 fixed. This was due to mishandling of the extra N_SO stabs output
4080 We also finally got Ultrix 4.2 running in house, and fixed core file
4081 support, with help from a dozen people on the net.
4083 John M. Farrell discovered that the reason that single-stepping was so
4084 slow on all of the Mips based platforms (primarily SGI and DEC) was
4085 that we were trying to demangle and lookup a symbol used for internal
4086 purposes on every instruction that was being stepped through. Changing
4087 the name of that symbol so that it couldn't be mistaken for a C++
4088 mangled symbol sped things up a great deal.
4090 Rich Pixley sped up symbol lookups in general by getting much smarter
4091 about when C++ symbol mangling is necessary. This should make symbol
4092 completion (TAB on the command line) much faster. It's not as fast as
4093 we'd like, but it's significantly faster than gdb-4.6.
4097 A new user controllable variable 'call_scratch_address' can
4098 specify the location of a scratch area to be used when GDB
4099 calls a function in the target. This is necessary because the
4100 usual method of putting the scratch area on the stack does not work
4101 in systems that have separate instruction and data spaces.
4103 We integrated changes to support the 29k UDI (Universal Debugger
4104 Interface), but discovered at the last minute that we didn't have all
4105 of the appropriate copyright paperwork. We are working with AMD to
4106 resolve this, and hope to have it available soon.
4110 We have sped up the remote serial line protocol, especially for targets
4111 with lots of registers. It now supports a new `expedited status' ('T')
4112 message which can be used in place of the existing 'S' status message.
4113 This allows the remote stub to send only the registers that GDB
4114 needs to make a quick decision about single-stepping or conditional
4115 breakpoints, eliminating the need to fetch the entire register set for
4116 each instruction being stepped through.
4118 The GDB remote serial protocol now implements a write-through cache for
4119 registers, only re-reading the registers if the target has run.
4121 There is also a new remote serial stub for SPARC processors. You can
4122 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4123 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4124 processor with a serial port.
4128 Configure.in files have become much easier to read and modify. A new
4129 `table driven' format makes it more obvious what configurations are
4130 supported, and what files each one uses.
4134 There is a new opcodes library which will eventually contain all of the
4135 disassembly routines and opcode tables. At present, it only contains
4136 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4137 disassembler (binutils/objdump) to share these routines.
4139 The libiberty library is now copylefted under the GNU Library General
4140 Public License. This allows more liberal use, and was done so libg++
4141 can use it. This makes no difference to GDB, since the Library License
4142 grants all the rights from the General Public License.
4146 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4147 reference to the stabs symbol info used by the debugger. It is (as far
4148 as we know) the only published document on this fascinating topic. We
4149 encourage you to read it, compare it to the stabs information on your
4150 system, and send improvements on the document in general (to
4151 bug-gdb@prep.ai.mit.edu).
4153 And, of course, many bugs have been fixed.
4156 *** Changes in GDB-4.6:
4158 * Better support for C++ function names
4160 GDB now accepts as input the "demangled form" of C++ overloaded function
4161 names and member function names, and can do command completion on such names
4162 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4163 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4164 Make use of command completion, it is your friend.
4166 GDB also now accepts a variety of C++ mangled symbol formats. They are
4167 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4168 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4169 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4170 for the list of formats.
4172 * G++ symbol mangling problem
4174 Recent versions of gcc have a bug in how they emit debugging information for
4175 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4176 directory) can be applied to gcc to fix the problem. Alternatively, if you
4177 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4178 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4179 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4182 * New 'maintenance' command
4184 All of the commands related to hacking GDB internals have been moved out of
4185 the main command set, and now live behind the 'maintenance' command. This
4186 can also be abbreviated as 'mt'. The following changes were made:
4188 dump-me -> maintenance dump-me
4189 info all-breakpoints -> maintenance info breakpoints
4190 printmsyms -> maintenance print msyms
4191 printobjfiles -> maintenance print objfiles
4192 printpsyms -> maintenance print psymbols
4193 printsyms -> maintenance print symbols
4195 The following commands are new:
4197 maintenance demangle Call internal GDB demangler routine to
4198 demangle a C++ link name and prints the result.
4199 maintenance print type Print a type chain for a given symbol
4201 * Change to .gdbinit file processing
4203 We now read the $HOME/.gdbinit file before processing the argv arguments
4204 (e.g. reading symbol files or core files). This allows global parameters to
4205 be set, which will apply during the symbol reading. The ./.gdbinit is still
4206 read after argv processing.
4208 * New hosts supported
4210 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4212 GNU/Linux support i386-unknown-linux or linux
4214 We are also including code to support the HP/PA running BSD and HPUX. This
4215 is almost guaranteed not to work, as we didn't have time to test or build it
4216 for this release. We are including it so that the more adventurous (or
4217 masochistic) of you can play with it. We also had major problems with the
4218 fact that the compiler that we got from HP doesn't support the -g option.
4221 * New targets supported
4223 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4225 * More smarts about finding #include files
4227 GDB now remembers the compilation directory for all include files, and for
4228 all files from which C is generated (like yacc and lex sources). This
4229 greatly improves GDB's ability to find yacc/lex sources, and include files,
4230 especially if you are debugging your program from a directory different from
4231 the one that contains your sources.
4233 We also fixed a bug which caused difficulty with listing and setting
4234 breakpoints in include files which contain C code. (In the past, you had to
4235 try twice in order to list an include file that you hadn't looked at before.)
4237 * Interesting infernals change
4239 GDB now deals with arbitrary numbers of sections, where the symbols for each
4240 section must be relocated relative to that section's landing place in the
4241 target's address space. This work was needed to support ELF with embedded
4242 stabs used by Solaris-2.0.
4244 * Bug fixes (of course!)
4246 There have been loads of fixes for the following things:
4247 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4248 i960, stabs, DOS(GO32), procfs, etc...
4250 See the ChangeLog for details.
4252 *** Changes in GDB-4.5:
4254 * New machines supported (host and target)
4256 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4258 SGI Irix-4.x mips-sgi-irix4 or iris4
4260 * New malloc package
4262 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4263 Mmalloc is capable of handling mutiple heaps of memory. It is also
4264 capable of saving a heap to a file, and then mapping it back in later.
4265 This can be used to greatly speedup the startup of GDB by using a
4266 pre-parsed symbol table which lives in a mmalloc managed heap. For
4267 more details, please read mmalloc/mmalloc.texi.
4271 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4272 'help info proc' for details.
4274 * MIPS ecoff symbol table format
4276 The code that reads MIPS symbol table format is now supported on all hosts.
4277 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4280 * File name changes for MS-DOS
4282 Many files in the config directories have been renamed to make it easier to
4283 support GDB on MS-DOSe systems (which have very restrictive file name
4284 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4285 environment) is close to working but has some remaining problems. Note
4286 that debugging of DOS programs is not supported, due to limitations
4287 in the ``operating system'', but it can be used to host cross-debugging.
4289 * Cross byte order fixes
4291 Many fixes have been made to support cross debugging of Sparc and MIPS
4292 targets from hosts whose byte order differs.
4294 * New -mapped and -readnow options
4296 If memory-mapped files are available on your system through the 'mmap'
4297 system call, you can use the -mapped option on the `file' or
4298 `symbol-file' commands to cause GDB to write the symbols from your
4299 program into a reusable file. If the program you are debugging is
4300 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4301 Future GDB debugging sessions will notice the presence of this file,
4302 and will quickly map in symbol information from it, rather than reading
4303 the symbol table from the executable program. Using the '-mapped'
4304 option in a GDB `file' or `symbol-file' command has the same effect as
4305 starting GDB with the '-mapped' command-line option.
4307 You can cause GDB to read the entire symbol table immediately by using
4308 the '-readnow' option with any of the commands that load symbol table
4309 information (or on the GDB command line). This makes the command
4310 slower, but makes future operations faster.
4312 The -mapped and -readnow options are typically combined in order to
4313 build a `fred.syms' file that contains complete symbol information.
4314 A simple GDB invocation to do nothing but build a `.syms' file for future
4317 gdb -batch -nx -mapped -readnow programname
4319 The `.syms' file is specific to the host machine on which GDB is run.
4320 It holds an exact image of GDB's internal symbol table. It cannot be
4321 shared across multiple host platforms.
4323 * longjmp() handling
4325 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4326 siglongjmp() without losing control. This feature has not yet been ported to
4327 all systems. It currently works on many 386 platforms, all MIPS-based
4328 platforms (SGI, DECstation, etc), and Sun3/4.
4332 Preliminary work has been put in to support the new Solaris OS from Sun. At
4333 this time, it can control and debug processes, but it is not capable of
4338 As always, many many bug fixes. The major areas were with g++, and mipsread.
4339 People using the MIPS-based platforms should experience fewer mysterious
4340 crashes and trashed symbol tables.
4342 *** Changes in GDB-4.4:
4344 * New machines supported (host and target)
4346 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4348 BSD Reno on Vax vax-dec-bsd
4349 Ultrix on Vax vax-dec-ultrix
4351 * New machines supported (target)
4353 AMD 29000 embedded, using EBMON a29k-none-none
4357 GDB continues to improve its handling of C++. `References' work better.
4358 The demangler has also been improved, and now deals with symbols mangled as
4359 per the Annotated C++ Reference Guide.
4361 GDB also now handles `stabs' symbol information embedded in MIPS
4362 `ecoff' symbol tables. Since the ecoff format was not easily
4363 extensible to handle new languages such as C++, this appeared to be a
4364 good way to put C++ debugging info into MIPS binaries. This option
4365 will be supported in the GNU C compiler, version 2, when it is
4368 * New features for SVR4
4370 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4371 shared libraries. Debugging dynamically linked programs should present
4372 only minor differences from debugging statically linked programs.
4374 The `info proc' command will print out information about any process
4375 on an SVR4 system (including the one you are debugging). At the moment,
4376 it prints the address mappings of the process.
4378 If you bring up GDB on another SVR4 system, please send mail to
4379 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4381 * Better dynamic linking support in SunOS
4383 Reading symbols from shared libraries which contain debugging symbols
4384 now works properly. However, there remain issues such as automatic
4385 skipping of `transfer vector' code during function calls, which
4386 make it harder to debug code in a shared library, than to debug the
4387 same code linked statically.
4391 GDB is now using the latest `getopt' routines from the FSF. This
4392 version accepts the -- prefix for options with long names. GDB will
4393 continue to accept the old forms (-option and +option) as well.
4394 Various single letter abbreviations for options have been explicity
4395 added to the option table so that they won't get overshadowed in the
4396 future by other options that begin with the same letter.
4400 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4401 Many assorted bugs have been handled. Many more remain to be handled.
4402 See the various ChangeLog files (primarily in gdb and bfd) for details.
4405 *** Changes in GDB-4.3:
4407 * New machines supported (host and target)
4409 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4410 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4411 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4413 * Almost SCO Unix support
4415 We had hoped to support:
4416 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4417 (except for core file support), but we discovered very late in the release
4418 that it has problems with process groups that render gdb unusable. Sorry
4419 about that. I encourage people to fix it and post the fixes.
4421 * Preliminary ELF and DWARF support
4423 GDB can read ELF object files on System V Release 4, and can handle
4424 debugging records for C, in DWARF format, in ELF files. This support
4425 is preliminary. If you bring up GDB on another SVR4 system, please
4426 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4431 GDB now uses the latest `readline' library. One user-visible change
4432 is that two tabs will list possible command completions, which previously
4433 required typing M-? (meta-question mark, or ESC ?).
4437 The `stepi' bug that many of you noticed has been squashed.
4438 Many bugs in C++ have been handled. Many more remain to be handled.
4439 See the various ChangeLog files (primarily in gdb and bfd) for details.
4441 * State of the MIPS world (in case you wondered):
4443 GDB can understand the symbol tables emitted by the compilers
4444 supplied by most vendors of MIPS-based machines, including DEC. These
4445 symbol tables are in a format that essentially nobody else uses.
4447 Some versions of gcc come with an assembler post-processor called
4448 mips-tfile. This program is required if you want to do source-level
4449 debugging of gcc-compiled programs. I believe FSF does not ship
4450 mips-tfile with gcc version 1, but it will eventually come with gcc
4453 Debugging of g++ output remains a problem. g++ version 1.xx does not
4454 really support it at all. (If you're lucky, you should be able to get
4455 line numbers and stack traces to work, but no parameters or local
4456 variables.) With some work it should be possible to improve the
4459 When gcc version 2 is released, you will have somewhat better luck.
4460 However, even then you will get confusing results for inheritance and
4463 We will eventually provide full debugging of g++ output on
4464 DECstations. This will probably involve some kind of stabs-in-ecoff
4465 encapulation, but the details have not been worked out yet.
4468 *** Changes in GDB-4.2:
4470 * Improved configuration
4472 Only one copy of `configure' exists now, and it is not self-modifying.
4473 Porting BFD is simpler.
4477 The `step' and `next' commands now only stop at the first instruction
4478 of a source line. This prevents the multiple stops that used to occur
4479 in switch statements, for-loops, etc. `Step' continues to stop if a
4480 function that has debugging information is called within the line.
4484 Lots of small bugs fixed. More remain.
4486 * New host supported (not target)
4488 Intel 386 PC clone running Mach i386-none-mach
4491 *** Changes in GDB-4.1:
4493 * Multiple source language support
4495 GDB now has internal scaffolding to handle several source languages.
4496 It determines the type of each source file from its filename extension,
4497 and will switch expression parsing and number formatting to match the
4498 language of the function in the currently selected stack frame.
4499 You can also specifically set the language to be used, with
4500 `set language c' or `set language modula-2'.
4504 GDB now has preliminary support for the GNU Modula-2 compiler,
4505 currently under development at the State University of New York at
4506 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4507 continue through the fall of 1991 and into 1992.
4509 Other Modula-2 compilers are currently not supported, and attempting to
4510 debug programs compiled with them will likely result in an error as the
4511 symbol table is read. Feel free to work on it, though!
4513 There are hooks in GDB for strict type checking and range checking,
4514 in the `Modula-2 philosophy', but they do not currently work.
4518 GDB can now write to executable and core files (e.g. patch
4519 a variable's value). You must turn this switch on, specify
4520 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4521 by assigning a new value to a variable. Modifications take
4524 * Automatic SunOS shared library reading
4526 When you run your program, GDB automatically determines where its
4527 shared libraries (if any) have been loaded, and reads their symbols.
4528 The `share' command is no longer needed. This also works when
4529 examining core files.
4533 You can specify the number of lines that the `list' command shows.
4536 * New machines supported (host and target)
4538 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4539 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4540 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4542 * New hosts supported (not targets)
4544 IBM RT/PC: romp-ibm-aix or rtpc
4546 * New targets supported (not hosts)
4548 AMD 29000 embedded with COFF a29k-none-coff
4549 AMD 29000 embedded with a.out a29k-none-aout
4550 Ultracomputer remote kernel debug a29k-nyu-kern
4552 * New remote interfaces
4558 *** Changes in GDB-4.0:
4562 Wide output is wrapped at good places to make the output more readable.
4564 Gdb now supports cross-debugging from a host machine of one type to a
4565 target machine of another type. Communication with the target system
4566 is over serial lines. The ``target'' command handles connecting to the
4567 remote system; the ``load'' command will download a program into the
4568 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4569 also supports debugging of realtime processes running under VxWorks,
4570 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4571 stub on the target system.
4573 New CPUs supported include the AMD 29000 and Intel 960.
4575 GDB now reads object files and symbol tables via a ``binary file''
4576 library, which allows a single copy of GDB to debug programs of multiple
4577 object file types such as a.out and coff.
4579 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4580 refcard.dvi and refcard.ps are available to format it).
4583 * Control-Variable user interface simplified
4585 All variables that control the operation of the debugger can be set
4586 by the ``set'' command, and displayed by the ``show'' command.
4588 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4589 ``Show prompt'' produces the response:
4590 Gdb's prompt is new-gdb=>.
4592 What follows are the NEW set commands. The command ``help set'' will
4593 print a complete list of old and new set commands. ``help set FOO''
4594 will give a longer description of the variable FOO. ``show'' will show
4595 all of the variable descriptions and their current settings.
4597 confirm on/off: Enables warning questions for operations that are
4598 hard to recover from, e.g. rerunning the program while
4599 it is already running. Default is ON.
4601 editing on/off: Enables EMACS style command line editing
4602 of input. Previous lines can be recalled with
4603 control-P, the current line can be edited with control-B,
4604 you can search for commands with control-R, etc.
4607 history filename NAME: NAME is where the gdb command history
4608 will be stored. The default is .gdb_history,
4609 or the value of the environment variable
4612 history size N: The size, in commands, of the command history. The
4613 default is 256, or the value of the environment variable
4616 history save on/off: If this value is set to ON, the history file will
4617 be saved after exiting gdb. If set to OFF, the
4618 file will not be saved. The default is OFF.
4620 history expansion on/off: If this value is set to ON, then csh-like
4621 history expansion will be performed on
4622 command line input. The default is OFF.
4624 radix N: Sets the default radix for input and output. It can be set
4625 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4626 in the current radix, so "set radix 10" is always a no-op.
4628 height N: This integer value is the number of lines on a page. Default
4629 is 24, the current `stty rows'' setting, or the ``li#''
4630 setting from the termcap entry matching the environment
4633 width N: This integer value is the number of characters on a line.
4634 Default is 80, the current `stty cols'' setting, or the ``co#''
4635 setting from the termcap entry matching the environment
4638 Note: ``set screensize'' is obsolete. Use ``set height'' and
4639 ``set width'' instead.
4641 print address on/off: Print memory addresses in various command displays,
4642 such as stack traces and structure values. Gdb looks
4643 more ``symbolic'' if you turn this off; it looks more
4644 ``machine level'' with it on. Default is ON.
4646 print array on/off: Prettyprint arrays. New convenient format! Default
4649 print demangle on/off: Print C++ symbols in "source" form if on,
4652 print asm-demangle on/off: Same, for assembler level printouts
4655 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4658 * Support for Epoch Environment.
4660 The epoch environment is a version of Emacs v18 with windowing. One
4661 new command, ``inspect'', is identical to ``print'', except that if you
4662 are running in the epoch environment, the value is printed in its own
4666 * Support for Shared Libraries
4668 GDB can now debug programs and core files that use SunOS shared libraries.
4669 Symbols from a shared library cannot be referenced
4670 before the shared library has been linked with the program (this
4671 happens after you type ``run'' and before the function main() is entered).
4672 At any time after this linking (including when examining core files
4673 from dynamically linked programs), gdb reads the symbols from each
4674 shared library when you type the ``sharedlibrary'' command.
4675 It can be abbreviated ``share''.
4677 sharedlibrary REGEXP: Load shared object library symbols for files
4678 matching a unix regular expression. No argument
4679 indicates to load symbols for all shared libraries.
4681 info sharedlibrary: Status of loaded shared libraries.
4686 A watchpoint stops execution of a program whenever the value of an
4687 expression changes. Checking for this slows down execution
4688 tremendously whenever you are in the scope of the expression, but is
4689 quite useful for catching tough ``bit-spreader'' or pointer misuse
4690 problems. Some machines such as the 386 have hardware for doing this
4691 more quickly, and future versions of gdb will use this hardware.
4693 watch EXP: Set a watchpoint (breakpoint) for an expression.
4695 info watchpoints: Information about your watchpoints.
4697 delete N: Deletes watchpoint number N (same as breakpoints).
4698 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4699 enable N: Re-enables watchpoint number N (same as breakpoints).
4702 * C++ multiple inheritance
4704 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4707 * C++ exception handling
4709 Gdb now supports limited C++ exception handling. Besides the existing
4710 ability to breakpoint on an exception handler, gdb can breakpoint on
4711 the raising of an exception (before the stack is peeled back to the
4714 catch FOO: If there is a FOO exception handler in the dynamic scope,
4715 set a breakpoint to catch exceptions which may be raised there.
4716 Multiple exceptions (``catch foo bar baz'') may be caught.
4718 info catch: Lists all exceptions which may be caught in the
4719 current stack frame.
4722 * Minor command changes
4724 The command ``call func (arg, arg, ...)'' now acts like the print
4725 command, except it does not print or save a value if the function's result
4726 is void. This is similar to dbx usage.
4728 The ``up'' and ``down'' commands now always print the frame they end up
4729 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4730 frames without printing.
4732 * New directory command
4734 'dir' now adds directories to the FRONT of the source search path.
4735 The path starts off empty. Source files that contain debug information
4736 about the directory in which they were compiled can be found even
4737 with an empty path; Sun CC and GCC include this information. If GDB can't
4738 find your source file in the current directory, type "dir .".
4740 * Configuring GDB for compilation
4742 For normal use, type ``./configure host''. See README or gdb.texinfo
4745 GDB now handles cross debugging. If you are remotely debugging between
4746 two different machines, type ``./configure host -target=targ''.
4747 Host is the machine where GDB will run; targ is the machine
4748 where the program that you are debugging will run.