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
70 ** "*stopped" events can report several new "reason"s, such as
73 ** Breakpoint changes are now notified using new async records, like
74 "=breakpoint-modified".
76 ** New command -ada-task-info.
78 * libthread-db-search-path now supports two special values: $sdir and $pdir.
79 $sdir specifies the default system locations of shared libraries.
80 $pdir specifies the directory where the libpthread used by the application
83 GDB no longer looks in $sdir and $pdir after it has searched the directories
84 mentioned in libthread-db-search-path. If you want to search those
85 directories, they must be specified in libthread-db-search-path.
86 The default value of libthread-db-search-path on GNU/Linux and Solaris
87 systems is now "$sdir:$pdir".
89 $pdir is not supported by gdbserver, it is currently ignored.
90 $sdir is supported by gdbserver.
92 * New configure option --with-iconv-bin.
93 When using the internationalization support like the one in the GNU C
94 library, GDB will invoke the "iconv" program to get a list of supported
95 character sets. If this program lives in a non-standard location, one can
96 use this option to specify where to find it.
98 * When natively debugging programs on PowerPC BookE processors running
99 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
100 watchpoints, which specify a mask in addition to an address to watch.
101 The mask specifies that some bits of an address (the bits which are
102 reset in the mask) should be ignored when matching the address accessed
103 by the inferior against the watchpoint address. See the "PowerPC Embedded"
104 section in the user manual for more details.
106 * The new option --once causes GDBserver to stop listening for connections once
107 the first connection is made. The listening port used by GDBserver will
108 become available after that.
110 * New commands "info macros" and "alias" have been added.
112 * New function parameters suffix @entry specifies value of function parameter
113 at the time the function got called. Entry values are available only since
119 "!" is now an alias of the "shell" command.
120 Note that no space is needed between "!" and SHELL COMMAND.
124 watch EXPRESSION mask MASK_VALUE
125 The watch command now supports the mask argument which allows creation
126 of masked watchpoints, if the current architecture supports this feature.
128 info auto-load-scripts [REGEXP]
129 This command was formerly named "maintenance print section-scripts".
130 It is now generally useful and is no longer a maintenance-only command.
132 info macro [-all] [--] MACRO
133 The info macro command has new options `-all' and `--'. The first for
134 printing all definitions of a macro. The second for explicitly specifying
135 the end of arguments and the beginning of the macro name in case the macro
136 name starts with a hyphen.
138 collect[/s] EXPRESSIONS
139 The tracepoint collect command now takes an optional modifier "/s"
140 that directs it to dereference pointer-to-character types and
141 collect the bytes of memory up to a zero byte. The behavior is
142 similar to what you see when you use the regular print command on a
143 string. An optional integer following the "/s" sets a bound on the
144 number of bytes that will be collected.
147 The trace start command now interprets any supplied arguments as a
148 note to be recorded with the trace run, with an effect similar to
149 setting the variable trace-notes.
152 The trace stop command now interprets any arguments as a note to be
153 mentioned along with the tstatus report that the trace was stopped
154 with a command. The effect is similar to setting the variable
157 * Tracepoints can now be enabled and disabled at any time after a trace
158 experiment has been started using the standard "enable" and "disable"
159 commands. It is now possible to start a trace experiment with no enabled
160 tracepoints; GDB will display a warning, but will allow the experiment to
161 begin, assuming that tracepoints will be enabled as needed while the trace
164 * Fast tracepoints on 32-bit x86-architectures can now be placed at
165 locations with 4-byte instructions, when they were previously
166 limited to locations with instructions of 5 bytes or longer.
172 Set the GDB prompt, and allow escape sequences to be inserted to
173 display miscellaneous information (see 'help set extended-prompt'
174 for the list of sequences). This prompt (and any information
175 accessed through the escape sequences) is updated every time the
178 set print entry-values (both|compact|default|if-needed|no|only|preferred)
179 show print entry-values
180 Set printing of frame argument values at function entry. In some cases
181 GDB can determine the value of function argument which was passed by the
182 function caller, even if the value was modified inside the called function.
184 set debug entry-values
185 show debug entry-values
186 Control display of debugging info for determining frame argument values at
187 function entry and virtual tail call frames.
189 set basenames-may-differ
190 show basenames-may-differ
191 Set whether a source file may have multiple base names.
192 (A "base name" is the name of a file with the directory part removed.
193 Example: The base name of "/home/user/hello.c" is "hello.c".)
194 If set, GDB will canonicalize file names (e.g., expand symlinks)
195 before comparing them. Canonicalization is an expensive operation,
196 but it allows the same file be known by more than one base name.
197 If not set (the default), all source files are assumed to have just
198 one base name, and gdb will do file name comparisons more efficiently.
204 Set a user name and notes for the current and any future trace runs.
205 This is useful for long-running and/or disconnected traces, to
206 inform others (or yourself) as to who is running the trace, supply
207 contact information, or otherwise explain what is going on.
210 show trace-stop-notes
211 Set a note attached to the trace run, that is displayed when the
212 trace has been stopped by a tstop command. This is useful for
213 instance as an explanation, if you are stopping a trace run that was
214 started by someone else.
220 Dynamically enable a tracepoint in a started trace experiment.
224 Dynamically disable a tracepoint in a started trace experiment.
228 Set the user and notes of the trace run.
232 Query the current status of a tracepoint.
236 Query the minimum length of instruction at which a fast tracepoint may
239 * Dcache size (number of lines) and line-size are now runtime-configurable
240 via "set dcache line" and "set dcache line-size" commands.
244 Texas Instruments TMS320C6x tic6x-*-*
248 Renesas RL78 rl78-*-elf
250 *** Changes in GDB 7.3.1
252 * The build failure for NetBSD and OpenBSD targets have now been fixed.
254 *** Changes in GDB 7.3
256 * GDB has a new command: "thread find [REGEXP]".
257 It finds the thread id whose name, target id, or thread extra info
258 matches the given regular expression.
260 * The "catch syscall" command now works on mips*-linux* targets.
262 * The -data-disassemble MI command now supports modes 2 and 3 for
263 dumping the instruction opcodes.
265 * New command line options
267 -data-directory DIR Specify DIR as the "data-directory".
268 This is mostly for testing purposes.
270 * The "maint set python auto-load on|off" command has been renamed to
271 "set auto-load-scripts on|off".
273 * GDB has a new command: "set directories".
274 It is like the "dir" command except that it replaces the
275 source path list instead of augmenting it.
277 * GDB now understands thread names.
279 On GNU/Linux, "info threads" will display the thread name as set by
280 prctl or pthread_setname_np.
282 There is also a new command, "thread name", which can be used to
283 assign a name internally for GDB to display.
286 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
287 has been integrated into GDB.
291 ** The function gdb.Write now accepts an optional keyword 'stream'.
292 This keyword, when provided, will direct the output to either
293 stdout, stderr, or GDB's logging output.
295 ** Parameters can now be be sub-classed in Python, and in particular
296 you may implement the get_set_doc and get_show_doc functions.
297 This improves how Parameter set/show documentation is processed
298 and allows for more dynamic content.
300 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
301 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
302 have an is_valid method.
304 ** Breakpoints can now be sub-classed in Python, and in particular
305 you may implement a 'stop' function that is executed each time
306 the inferior reaches that breakpoint.
308 ** New function gdb.lookup_global_symbol looks up a global symbol.
310 ** GDB values in Python are now callable if the value represents a
311 function. For example, if 'some_value' represents a function that
312 takes two integer parameters and returns a value, you can call
313 that function like so:
315 result = some_value (10,20)
317 ** Module gdb.types has been added.
318 It contains a collection of utilities for working with gdb.Types objects:
319 get_basic_type, has_field, make_enum_dict.
321 ** Module gdb.printing has been added.
322 It contains utilities for writing and registering pretty-printers.
323 New classes: PrettyPrinter, SubPrettyPrinter,
324 RegexpCollectionPrettyPrinter.
325 New function: register_pretty_printer.
327 ** New commands "info pretty-printers", "enable pretty-printer" and
328 "disable pretty-printer" have been added.
330 ** gdb.parameter("directories") is now available.
332 ** New function gdb.newest_frame returns the newest frame in the
335 ** The gdb.InferiorThread class has a new "name" attribute. This
336 holds the thread's name.
338 ** Python Support for Inferior events.
339 Python scripts can add observers to be notified of events
340 occurring in the process being debugged.
341 The following events are currently supported:
342 - gdb.events.cont Continue event.
343 - gdb.events.exited Inferior exited event.
344 - gdb.events.stop Signal received, and Breakpoint hit events.
348 ** GDB now puts template parameters in scope when debugging in an
349 instantiation. For example, if you have:
351 template<int X> int func (void) { return X; }
353 then if you step into func<5>, "print X" will show "5". This
354 feature requires proper debuginfo support from the compiler; it
355 was added to GCC 4.5.
357 ** The motion commands "next", "finish", "until", and "advance" now
358 work better when exceptions are thrown. In particular, GDB will
359 no longer lose control of the inferior; instead, the GDB will
360 stop the inferior at the point at which the exception is caught.
361 This functionality requires a change in the exception handling
362 code that was introduced in GCC 4.5.
364 * GDB now follows GCC's rules on accessing volatile objects when
365 reading or writing target state during expression evaluation.
366 One notable difference to prior behavior is that "print x = 0"
367 no longer generates a read of x; the value of the assignment is
368 now always taken directly from the value being assigned.
370 * GDB now has some support for using labels in the program's source in
371 linespecs. For instance, you can use "advance label" to continue
372 execution to a label.
374 * GDB now has support for reading and writing a new .gdb_index
375 section. This section holds a fast index of DWARF debugging
376 information and can be used to greatly speed up GDB startup and
377 operation. See the documentation for `save gdb-index' for details.
379 * The "watch" command now accepts an optional "-location" argument.
380 When used, this causes GDB to watch the memory referred to by the
381 expression. Such a watchpoint is never deleted due to it going out
384 * GDB now supports thread debugging of core dumps on GNU/Linux.
386 GDB now activates thread debugging using the libthread_db library
387 when debugging GNU/Linux core dumps, similarly to when debugging
388 live processes. As a result, when debugging a core dump file, GDB
389 is now able to display pthread_t ids of threads. For example, "info
390 threads" shows the same output as when debugging the process when it
391 was live. In earlier releases, you'd see something like this:
394 * 1 LWP 6780 main () at main.c:10
396 While now you see this:
399 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
401 It is also now possible to inspect TLS variables when debugging core
404 When debugging a core dump generated on a machine other than the one
405 used to run GDB, you may need to point GDB at the correct
406 libthread_db library with the "set libthread-db-search-path"
407 command. See the user manual for more details on this command.
409 * When natively debugging programs on PowerPC BookE processors running
410 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
411 which stop execution of the inferior whenever it executes an instruction
412 at any address within the specified range. See the "PowerPC Embedded"
413 section in the user manual for more details.
415 * New features in the GDB remote stub, GDBserver
417 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
418 and i686 LynxOS (version 5.x).
420 ** GDBserver is now supported on Blackfin Linux.
422 * New native configurations
424 ia64 HP-UX ia64-*-hpux*
428 Analog Devices, Inc. Blackfin Processor bfin-*
430 * Ada task switching is now supported on sparc-elf targets when
431 debugging a program using the Ravenscar Profile. For more information,
432 see the "Tasking Support when using the Ravenscar Profile" section
433 in the GDB user manual.
435 * Guile support was removed.
437 * New features in the GNU simulator
439 ** The --map-info flag lists all known core mappings.
441 ** CFI flashes may be simulated via the "cfi" device.
443 *** Changes in GDB 7.2
445 * Shared library support for remote targets by default
447 When GDB is configured for a generic, non-OS specific target, like
448 for example, --target=arm-eabi or one of the many *-*-elf targets,
449 GDB now queries remote stubs for loaded shared libraries using the
450 `qXfer:libraries:read' packet. Previously, shared library support
451 was always disabled for such configurations.
455 ** Argument Dependent Lookup (ADL)
457 In C++ ADL lookup directs function search to the namespaces of its
458 arguments even if the namespace has not been imported.
468 Here the compiler will search for `foo' in the namespace of 'b'
469 and find A::foo. GDB now supports this. This construct is commonly
470 used in the Standard Template Library for operators.
472 ** Improved User Defined Operator Support
474 In addition to member operators, GDB now supports lookup of operators
475 defined in a namespace and imported with a `using' directive, operators
476 defined in the global scope, operators imported implicitly from an
477 anonymous namespace, and the ADL operators mentioned in the previous
479 GDB now also supports proper overload resolution for all the previously
480 mentioned flavors of operators.
482 ** static const class members
484 Printing of static const class members that are initialized in the
485 class definition has been fixed.
487 * Windows Thread Information Block access.
489 On Windows targets, GDB now supports displaying the Windows Thread
490 Information Block (TIB) structure. This structure is visible either
491 by using the new command `info w32 thread-information-block' or, by
492 dereferencing the new convenience variable named `$_tlb', a
493 thread-specific pointer to the TIB. This feature is also supported
494 when remote debugging using GDBserver.
498 Static tracepoints are calls in the user program into a tracing
499 library. One such library is a port of the LTTng kernel tracer to
500 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
501 When debugging with GDBserver, GDB now supports combining the GDB
502 tracepoint machinery with such libraries. For example: the user can
503 use GDB to probe a static tracepoint marker (a call from the user
504 program into the tracing library) with the new "strace" command (see
505 "New commands" below). This creates a "static tracepoint" in the
506 breakpoint list, that can be manipulated with the same feature set
507 as fast and regular tracepoints. E.g., collect registers, local and
508 global variables, collect trace state variables, and define
509 tracepoint conditions. In addition, the user can collect extra
510 static tracepoint marker specific data, by collecting the new
511 $_sdata internal variable. When analyzing the trace buffer, you can
512 inspect $_sdata like any other variable available to GDB. For more
513 information, see the "Tracepoints" chapter in GDB user manual. New
514 remote packets have been defined to support static tracepoints, see
515 the "New remote packets" section below.
517 * Better reconstruction of tracepoints after disconnected tracing
519 GDB will attempt to download the original source form of tracepoint
520 definitions when starting a trace run, and then will upload these
521 upon reconnection to the target, resulting in a more accurate
522 reconstruction of the tracepoints that are in use on the target.
526 You can now exercise direct control over the ways that GDB can
527 affect your program. For instance, you can disallow the setting of
528 breakpoints, so that the program can run continuously (assuming
529 non-stop mode). In addition, the "observer" variable is available
530 to switch all of the different controls; in observer mode, GDB
531 cannot affect the target's behavior at all, which is useful for
532 tasks like diagnosing live systems in the field.
534 * The new convenience variable $_thread holds the number of the
541 Return the address of the Windows Thread Information Block of a given thread.
545 In response to several of the tracepoint packets, the target may now
546 also respond with a number of intermediate `qRelocInsn' request
547 packets before the final result packet, to have GDB handle
548 relocating an instruction to execute at a different address. This
549 is particularly useful for stubs that support fast tracepoints. GDB
550 reports support for this feature in the qSupported packet.
554 List static tracepoint markers in the target program.
558 List static tracepoint markers at a given address in the target
561 qXfer:statictrace:read
563 Read the static trace data collected (by a `collect $_sdata'
564 tracepoint action). The remote stub reports support for this packet
565 to gdb's qSupported query.
569 Send the current settings of GDB's permission flags.
573 Send part of the source (textual) form of a tracepoint definition,
574 which includes location, conditional, and action list.
576 * The source command now accepts a -s option to force searching for the
577 script in the source search path even if the script name specifies
580 * New features in the GDB remote stub, GDBserver
582 - GDBserver now support tracepoints (including fast tracepoints, and
583 static tracepoints). The feature is currently supported by the
584 i386-linux and amd64-linux builds. See the "Tracepoints support
585 in gdbserver" section in the manual for more information.
587 GDBserver JIT compiles the tracepoint's conditional agent
588 expression bytecode into native code whenever possible for low
589 overhead dynamic tracepoints conditionals. For such tracepoints,
590 an expression that examines program state is evaluated when the
591 tracepoint is reached, in order to determine whether to capture
592 trace data. If the condition is simple and false, processing the
593 tracepoint finishes very quickly and no data is gathered.
595 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
596 for static tracepoints support.
598 - GDBserver now supports x86_64 Windows 64-bit debugging.
600 * GDB now sends xmlRegisters= in qSupported packet to indicate that
601 it understands register description.
603 * The --batch flag now disables pagination and queries.
605 * X86 general purpose registers
607 GDB now supports reading/writing byte, word and double-word x86
608 general purpose registers directly. This means you can use, say,
609 $ah or $ax to refer, respectively, to the byte register AH and
610 16-bit word register AX that are actually portions of the 32-bit
611 register EAX or 64-bit register RAX.
613 * The `commands' command now accepts a range of breakpoints to modify.
614 A plain `commands' following a command that creates multiple
615 breakpoints affects all the breakpoints set by that command. This
616 applies to breakpoints set by `rbreak', and also applies when a
617 single `break' command creates multiple breakpoints (e.g.,
618 breakpoints on overloaded c++ functions).
620 * The `rbreak' command now accepts a filename specification as part of
621 its argument, limiting the functions selected by the regex to those
622 in the specified file.
624 * Support for remote debugging Windows and SymbianOS shared libraries
625 from Unix hosts has been improved. Non Windows GDB builds now can
626 understand target reported file names that follow MS-DOS based file
627 system semantics, such as file names that include drive letters and
628 use the backslash character as directory separator. This makes it
629 possible to transparently use the "set sysroot" and "set
630 solib-search-path" on Unix hosts to point as host copies of the
631 target's shared libraries. See the new command "set
632 target-file-system-kind" described below, and the "Commands to
633 specify files" section in the user manual for more information.
637 eval template, expressions...
638 Convert the values of one or more expressions under the control
639 of the string template to a command line, and call it.
641 set target-file-system-kind unix|dos-based|auto
642 show target-file-system-kind
643 Set or show the assumed file system kind for target reported file
646 save breakpoints <filename>
647 Save all current breakpoint definitions to a file suitable for use
648 in a later debugging session. To read the saved breakpoint
649 definitions, use the `source' command.
651 `save tracepoints' is a new alias for `save-tracepoints'. The latter
654 info static-tracepoint-markers
655 Display information about static tracepoint markers in the target.
657 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
658 Define a static tracepoint by probing a marker at the given
659 function, line, address, or marker ID.
663 Enable and disable observer mode.
665 set may-write-registers on|off
666 set may-write-memory on|off
667 set may-insert-breakpoints on|off
668 set may-insert-tracepoints on|off
669 set may-insert-fast-tracepoints on|off
670 set may-interrupt on|off
671 Set individual permissions for GDB effects on the target. Note that
672 some of these settings can have undesirable or surprising
673 consequences, particularly when changed in the middle of a session.
674 For instance, disabling the writing of memory can prevent
675 breakpoints from being inserted, cause single-stepping to fail, or
676 even crash your program, if you disable after breakpoints have been
677 inserted. However, GDB should not crash.
679 set record memory-query on|off
680 show record memory-query
681 Control whether to stop the inferior if memory changes caused
682 by an instruction cannot be recorded.
687 The disassemble command now supports "start,+length" form of two arguments.
691 ** GDB now provides a new directory location, called the python directory,
692 where Python scripts written for GDB can be installed. The location
693 of that directory is <data-directory>/python, where <data-directory>
694 is the GDB data directory. For more details, see section `Scripting
695 GDB using Python' in the manual.
697 ** The GDB Python API now has access to breakpoints, symbols, symbol
698 tables, program spaces, inferiors, threads and frame's code blocks.
699 Additionally, GDB Parameters can now be created from the API, and
700 manipulated via set/show in the CLI.
702 ** New functions gdb.target_charset, gdb.target_wide_charset,
703 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
705 ** New exception gdb.GdbError.
707 ** Pretty-printers are now also looked up in the current program space.
709 ** Pretty-printers can now be individually enabled and disabled.
711 ** GDB now looks for names of Python scripts to auto-load in a
712 special section named `.debug_gdb_scripts', in addition to looking
713 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
715 * Tracepoint actions were unified with breakpoint commands. In particular,
716 there are no longer differences in "info break" output for breakpoints and
717 tracepoints and the "commands" command can be used for both tracepoints and
722 ARM Symbian arm*-*-symbianelf*
724 * D language support.
725 GDB now supports debugging programs written in the D programming
728 * GDB now supports the extended ptrace interface for PowerPC which is
729 available since Linux kernel version 2.6.34. This automatically enables
730 any hardware breakpoints and additional hardware watchpoints available in
731 the processor. The old ptrace interface exposes just one hardware
732 watchpoint and no hardware breakpoints.
734 * GDB is now able to use the Data Value Compare (DVC) register available on
735 embedded PowerPC processors to implement in hardware simple watchpoint
736 conditions of the form:
738 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
740 This works in native GDB running on Linux kernels with the extended ptrace
741 interface mentioned above.
743 *** Changes in GDB 7.1
749 GDB now supports importing of namespaces in C++. This enables the
750 user to inspect variables from imported namespaces. Support for
751 namepace aliasing has also been added. So, if a namespace is
752 aliased in the current scope (e.g. namepace C=A; ) the user can
753 print variables using the alias (e.g. (gdb) print C::x).
757 All known bugs relating to the printing of virtual base class were
758 fixed. It is now possible to call overloaded static methods using a
763 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
764 and reinterpret_cast<> are now handled by the C++ expression parser.
768 Xilinx MicroBlaze microblaze-*-*
773 Xilinx MicroBlaze microblaze
776 * Multi-program debugging.
778 GDB now has support for multi-program (a.k.a. multi-executable or
779 multi-exec) debugging. This allows for debugging multiple inferiors
780 simultaneously each running a different program under the same GDB
781 session. See "Debugging Multiple Inferiors and Programs" in the
782 manual for more information. This implied some user visible changes
783 in the multi-inferior support. For example, "info inferiors" now
784 lists inferiors that are not running yet or that have exited
785 already. See also "New commands" and "New options" below.
787 * New tracing features
789 GDB's tracepoint facility now includes several new features:
791 ** Trace state variables
793 GDB tracepoints now include support for trace state variables, which
794 are variables managed by the target agent during a tracing
795 experiment. They are useful for tracepoints that trigger each
796 other, so for instance one tracepoint can count hits in a variable,
797 and then a second tracepoint has a condition that is true when the
798 count reaches a particular value. Trace state variables share the
799 $-syntax of GDB convenience variables, and can appear in both
800 tracepoint actions and condition expressions. Use the "tvariable"
801 command to create, and "info tvariables" to view; see "Trace State
802 Variables" in the manual for more detail.
806 GDB now includes an option for defining fast tracepoints, which
807 targets may implement more efficiently, such as by installing a jump
808 into the target agent rather than a trap instruction. The resulting
809 speedup can be by two orders of magnitude or more, although the
810 tradeoff is that some program locations on some target architectures
811 might not allow fast tracepoint installation, for instance if the
812 instruction to be replaced is shorter than the jump. To request a
813 fast tracepoint, use the "ftrace" command, with syntax identical to
814 the regular trace command.
816 ** Disconnected tracing
818 It is now possible to detach GDB from the target while it is running
819 a trace experiment, then reconnect later to see how the experiment
820 is going. In addition, a new variable disconnected-tracing lets you
821 tell the target agent whether to continue running a trace if the
822 connection is lost unexpectedly.
826 GDB now has the ability to save the trace buffer into a file, and
827 then use that file as a target, similarly to you can do with
828 corefiles. You can select trace frames, print data that was
829 collected in them, and use tstatus to display the state of the
830 tracing run at the moment that it was saved. To create a trace
831 file, use "tsave <filename>", and to use it, do "target tfile
834 ** Circular trace buffer
836 You can ask the target agent to handle the trace buffer as a
837 circular buffer, discarding the oldest trace frames to make room for
838 newer ones, by setting circular-trace-buffer to on. This feature may
839 not be available for all target agents.
844 The disassemble command, when invoked with two arguments, now requires
845 the arguments to be comma-separated.
848 The info variables command now displays variable definitions. Files
849 which only declare a variable are not shown.
852 The source command is now capable of sourcing Python scripts.
853 This feature is dependent on the debugger being build with Python
856 Related to this enhancement is also the introduction of a new command
857 "set script-extension" (see below).
859 * New commands (for set/show, see "New options" below)
861 record save [<FILENAME>]
862 Save a file (in core file format) containing the process record
863 execution log for replay debugging at a later time.
865 record restore <FILENAME>
866 Restore the process record execution log that was saved at an
867 earlier time, for replay debugging.
869 add-inferior [-copies <N>] [-exec <FILENAME>]
872 clone-inferior [-copies <N>] [ID]
873 Make a new inferior ready to execute the same program another
879 maint info program-spaces
880 List the program spaces loaded into GDB.
882 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
883 show remote interrupt-sequence
884 Allow the user to select one of ^C, a BREAK signal or BREAK-g
885 as the sequence to the remote target in order to interrupt the execution.
886 Ctrl-C is a default. Some system prefers BREAK which is high level of
887 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
888 Magic SysRq g. It is BREAK signal and character 'g'.
890 set remote interrupt-on-connect [on | off]
891 show remote interrupt-on-connect
892 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
893 remote target when gdb connects to it. This is needed when you debug
896 set remotebreak [on | off]
898 Deprecated. Use "set/show remote interrupt-sequence" instead.
900 tvariable $NAME [ = EXP ]
901 Create or modify a trace state variable.
904 List trace state variables and their values.
906 delete tvariable $NAME ...
907 Delete one or more trace state variables.
910 Evaluate the given expressions without collecting anything into the
911 trace buffer. (Valid in tracepoint actions only.)
913 ftrace FN / FILE:LINE / *ADDR
914 Define a fast tracepoint at the given function, line, or address.
916 * New expression syntax
918 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
919 GDB now parses 0b101010 identically with 42.
923 set follow-exec-mode new|same
924 show follow-exec-mode
925 Control whether GDB reuses the same inferior across an exec call or
926 creates a new one. This is useful to be able to restart the old
927 executable after the inferior having done an exec call.
929 set default-collect EXPR, ...
931 Define a list of expressions to be collected at each tracepoint.
932 This is a useful way to ensure essential items are not overlooked,
933 such as registers or a critical global variable.
935 set disconnected-tracing
936 show disconnected-tracing
937 If set to 1, the target is instructed to continue tracing if it
938 loses its connection to GDB. If 0, the target is to stop tracing
941 set circular-trace-buffer
942 show circular-trace-buffer
943 If set to on, the target is instructed to use a circular trace buffer
944 and discard the oldest trace frames instead of stopping the trace due
945 to a full trace buffer. If set to off, the trace stops when the buffer
946 fills up. Some targets may not support this.
948 set script-extension off|soft|strict
949 show script-extension
950 If set to "off", the debugger does not perform any script language
951 recognition, and all sourced files are assumed to be GDB scripts.
952 If set to "soft" (the default), files are sourced according to
953 filename extension, falling back to GDB scripts if the first
955 If set to "strict", files are sourced according to filename extension.
957 set ada trust-PAD-over-XVS on|off
958 show ada trust-PAD-over-XVS
959 If off, activate a workaround against a bug in the debugging information
960 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
961 the GCC sources for more information about the GNAT encoding and
962 PAD types in particular). It is always safe to set this option to
963 off, but this introduces a slight performance penalty. The default
966 * Python API Improvements
968 ** GDB provides the new class gdb.LazyString. This is useful in
969 some pretty-printing cases. The new method gdb.Value.lazy_string
970 provides a simple way to create objects of this type.
972 ** The fields returned by gdb.Type.fields now have an
973 `is_base_class' attribute.
975 ** The new method gdb.Type.range returns the range of an array type.
977 ** The new method gdb.parse_and_eval can be used to parse and
978 evaluate an expression.
983 Define a trace state variable.
986 Get the current value of a trace state variable.
989 Set desired tracing behavior upon disconnection.
992 Set the trace buffer to be linear or circular.
995 Get data about the tracepoints currently in use.
999 Process record now works correctly with hardware watchpoints.
1001 Multiple bug fixes have been made to the mips-irix port, making it
1002 much more reliable. In particular:
1003 - Debugging threaded applications is now possible again. Previously,
1004 GDB would hang while starting the program, or while waiting for
1005 the program to stop at a breakpoint.
1006 - Attaching to a running process no longer hangs.
1007 - An error occurring while loading a core file has been fixed.
1008 - Changing the value of the PC register now works again. This fixes
1009 problems observed when using the "jump" command, or when calling
1010 a function from GDB, or even when assigning a new value to $pc.
1011 - With the "finish" and "return" commands, the return value for functions
1012 returning a small array is now correctly printed.
1013 - It is now possible to break on shared library code which gets executed
1014 during a shared library init phase (code executed while executing
1015 their .init section). Previously, the breakpoint would have no effect.
1016 - GDB is now able to backtrace through the signal handler for
1017 non-threaded programs.
1019 PIE (Position Independent Executable) programs debugging is now supported.
1020 This includes debugging execution of PIC (Position Independent Code) shared
1021 libraries although for that, it should be possible to run such libraries as an
1024 *** Changes in GDB 7.0
1026 * GDB now has an interface for JIT compilation. Applications that
1027 dynamically generate code can create symbol files in memory and register
1028 them with GDB. For users, the feature should work transparently, and
1029 for JIT developers, the interface is documented in the GDB manual in the
1030 "JIT Compilation Interface" chapter.
1032 * Tracepoints may now be conditional. The syntax is as for
1033 breakpoints; either an "if" clause appended to the "trace" command,
1034 or the "condition" command is available. GDB sends the condition to
1035 the target for evaluation using the same bytecode format as is used
1036 for tracepoint actions.
1038 * The disassemble command now supports: an optional /r modifier, print the
1039 raw instructions in hex as well as in symbolic form, and an optional /m
1040 modifier to print mixed source+assembly.
1042 * Process record and replay
1044 In a architecture environment that supports ``process record and
1045 replay'', ``process record and replay'' target can record a log of
1046 the process execution, and replay it with both forward and reverse
1049 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1050 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1051 set execution-direction {forward|reverse}, for targets that support
1054 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1055 feature is available with a native GDB running on kernel version
1058 * GDB now has support for multi-byte and wide character sets on the
1059 target. Strings whose character type is wchar_t, char16_t, or
1060 char32_t are now correctly printed. GDB supports wide- and unicode-
1061 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1062 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1063 `printf'. This feature requires iconv to work properly; if your
1064 system does not have a working iconv, GDB can use GNU libiconv. See
1065 the installation instructions for more information.
1067 * GDB now supports automatic retrieval of shared library files from
1068 remote targets. To use this feature, specify a system root that begins
1069 with the `remote:' prefix, either via the `set sysroot' command or via
1070 the `--with-sysroot' configure-time option.
1072 * "info sharedlibrary" now takes an optional regex of libraries to show,
1073 and it now reports if a shared library has no debugging information.
1075 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1076 now complete on file names.
1078 * When completing in expressions, gdb will attempt to limit
1079 completions to allowable structure or union fields, where appropriate.
1080 For instance, consider:
1082 # struct example { int f1; double f2; };
1083 # struct example variable;
1086 If the user types TAB at the end of this command line, the available
1087 completions will be "f1" and "f2".
1089 * Inlined functions are now supported. They show up in backtraces, and
1090 the "step", "next", and "finish" commands handle them automatically.
1092 * GDB now supports the token-splicing (##) and stringification (#)
1093 operators when expanding macros. It also supports variable-arity
1096 * GDB now supports inspecting extra signal information, exported by
1097 the new $_siginfo convenience variable. The feature is currently
1098 implemented on linux ARM, i386 and amd64.
1100 * GDB can now display the VFP floating point registers and NEON vector
1101 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1102 can provide these registers (requires Linux 2.6.30 or later). Remote
1103 and simulator targets may also provide them.
1105 * New remote packets
1108 Search memory for a sequence of bytes.
1111 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1112 operation over reliable transport links. Use of this packet is
1113 controlled by the `set remote noack-packet' command.
1116 Kill the process with the specified process ID. Use this in preference
1117 to `k' when multiprocess protocol extensions are supported.
1120 Obtains additional operating system information
1124 Read or write additional signal information.
1126 * Removed remote protocol undocumented extension
1128 An undocumented extension to the remote protocol's `S' stop reply
1129 packet that permited the stub to pass a process id was removed.
1130 Remote servers should use the `T' stop reply packet instead.
1132 * GDB now supports multiple function calling conventions according to the
1133 DWARF-2 DW_AT_calling_convention function attribute.
1135 * The SH target utilizes the aforementioned change to distinguish between gcc
1136 and Renesas calling convention. It also adds the new CLI commands
1137 `set/show sh calling-convention'.
1139 * GDB can now read compressed debug sections, as produced by GNU gold
1140 with the --compress-debug-sections=zlib flag.
1142 * 64-bit core files are now supported on AIX.
1144 * Thread switching is now supported on Tru64.
1146 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1147 which will be allocated using malloc later in program execution.
1149 * The qXfer:libraries:read remote procotol packet now allows passing a
1150 list of section offsets.
1152 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1153 conditions handling signals delivered during attach or thread creation
1154 have also been fixed.
1156 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1157 From the user's standpoint, all unqualified instances of True and False
1158 are treated as the standard definitions, regardless of context.
1160 * GDB now parses C++ symbol and type names more flexibly. For
1163 template<typename T> class C { };
1166 GDB will now correctly handle all of:
1168 ptype C<char const *>
1169 ptype C<char const*>
1170 ptype C<const char *>
1171 ptype C<const char*>
1173 * New features in the GDB remote stub, gdbserver
1175 - The "--wrapper" command-line argument tells gdbserver to use a
1176 wrapper program to launch programs for debugging.
1178 - On PowerPC and S/390 targets, it is now possible to use a single
1179 gdbserver executable to debug both 32-bit and 64-bit programs.
1180 (This requires gdbserver itself to be built as a 64-bit executable.)
1182 - gdbserver uses the new noack protocol mode for TCP connections to
1183 reduce communications latency, if also supported and enabled in GDB.
1185 - Support for the sparc64-linux-gnu target is now included in
1188 - The amd64-linux build of gdbserver now supports debugging both
1189 32-bit and 64-bit programs.
1191 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1192 now support hardware watchpoints, and will use them automatically
1197 GDB now has support for scripting using Python. Whether this is
1198 available is determined at configure time.
1200 New GDB commands can now be written in Python.
1202 * Ada tasking support
1204 Ada tasks can now be inspected in GDB. The following commands have
1208 Print the list of Ada tasks.
1210 Print detailed information about task number N.
1212 Print the task number of the current task.
1214 Switch the context of debugging to task number N.
1216 * Support for user-defined prefixed commands. The "define" command can
1217 add new commands to existing prefixes, e.g. "target".
1219 * Multi-inferior, multi-process debugging.
1221 GDB now has generalized support for multi-inferior debugging. See
1222 "Debugging Multiple Inferiors" in the manual for more information.
1223 Although availability still depends on target support, the command
1224 set is more uniform now. The GNU/Linux specific multi-forks support
1225 has been migrated to this new framework. This implied some user
1226 visible changes; see "New commands" and also "Removed commands"
1229 * Target descriptions can now describe the target OS ABI. See the
1230 "Target Description Format" section in the user manual for more
1233 * Target descriptions can now describe "compatible" architectures
1234 to indicate that the target can execute applications for a different
1235 architecture in addition to those for the main target architecture.
1236 See the "Target Description Format" section in the user manual for
1239 * Multi-architecture debugging.
1241 GDB now includes general supports for debugging applications on
1242 hybrid systems that use more than one single processor architecture
1243 at the same time. Each such hybrid architecture still requires
1244 specific support to be added. The only hybrid architecture supported
1245 in this version of GDB is the Cell Broadband Engine.
1247 * GDB now supports integrated debugging of Cell/B.E. applications that
1248 use both the PPU and SPU architectures. To enable support for hybrid
1249 Cell/B.E. debugging, you need to configure GDB to support both the
1250 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1251 --enable-targets configure option.
1253 * Non-stop mode debugging.
1255 For some targets, GDB now supports an optional mode of operation in
1256 which you can examine stopped threads while other threads continue
1257 to execute freely. This is referred to as non-stop mode, with the
1258 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1259 section in the user manual for more information.
1261 To be able to support remote non-stop debugging, a remote stub needs
1262 to implement the non-stop mode remote protocol extensions, as
1263 described in the "Remote Non-Stop" section of the user manual. The
1264 GDB remote stub, gdbserver, has been adjusted to support these
1265 extensions on linux targets.
1267 * New commands (for set/show, see "New options" below)
1269 catch syscall [NAME(S) | NUMBER(S)]
1270 Catch system calls. Arguments, which should be names of system
1271 calls or their numbers, mean catch only those syscalls. Without
1272 arguments, every syscall will be caught. When the inferior issues
1273 any of the specified syscalls, GDB will stop and announce the system
1274 call, both when it is called and when its call returns. This
1275 feature is currently available with a native GDB running on the
1276 Linux Kernel, under the following architectures: x86, x86_64,
1277 PowerPC and PowerPC64.
1279 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1281 Search memory for a sequence of bytes.
1283 maint set python print-stack
1284 maint show python print-stack
1285 Show a stack trace when an error is encountered in a Python script.
1288 Invoke CODE by passing it to the Python interpreter.
1293 These allow macros to be defined, undefined, and listed
1297 Show operating system information about processes.
1300 List the inferiors currently under GDB's control.
1303 Switch focus to inferior number NUM.
1306 Detach from inferior number NUM.
1309 Kill inferior number NUM.
1313 set spu stop-on-load
1314 show spu stop-on-load
1315 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1317 set spu auto-flush-cache
1318 show spu auto-flush-cache
1319 Control whether to automatically flush the software-managed cache
1320 during Cell/B.E. debugging.
1322 set sh calling-convention
1323 show sh calling-convention
1324 Control the calling convention used when calling SH target functions.
1327 show debug timestamp
1328 Control display of timestamps with GDB debugging output.
1330 set disassemble-next-line
1331 show disassemble-next-line
1332 Control display of disassembled source lines or instructions when
1335 set remote noack-packet
1336 show remote noack-packet
1337 Set/show the use of remote protocol QStartNoAckMode packet. See above
1338 under "New remote packets."
1340 set remote query-attached-packet
1341 show remote query-attached-packet
1342 Control use of remote protocol `qAttached' (query-attached) packet.
1344 set remote read-siginfo-object
1345 show remote read-siginfo-object
1346 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1349 set remote write-siginfo-object
1350 show remote write-siginfo-object
1351 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1354 set remote reverse-continue
1355 show remote reverse-continue
1356 Control use of remote protocol 'bc' (reverse-continue) packet.
1358 set remote reverse-step
1359 show remote reverse-step
1360 Control use of remote protocol 'bs' (reverse-step) packet.
1362 set displaced-stepping
1363 show displaced-stepping
1364 Control displaced stepping mode. Displaced stepping is a way to
1365 single-step over breakpoints without removing them from the debuggee.
1366 Also known as "out-of-line single-stepping".
1369 show debug displaced
1370 Control display of debugging info for displaced stepping.
1372 maint set internal-error
1373 maint show internal-error
1374 Control what GDB does when an internal error is detected.
1376 maint set internal-warning
1377 maint show internal-warning
1378 Control what GDB does when an internal warning is detected.
1383 Use a wrapper program to launch programs for debugging.
1385 set multiple-symbols (all|ask|cancel)
1386 show multiple-symbols
1387 The value of this variable can be changed to adjust the debugger behavior
1388 when an expression or a breakpoint location contains an ambiguous symbol
1389 name (an overloaded function name, for instance).
1391 set breakpoint always-inserted
1392 show breakpoint always-inserted
1393 Keep breakpoints always inserted in the target, as opposed to inserting
1394 them when resuming the target, and removing them when the target stops.
1395 This option can improve debugger performance on slow remote targets.
1397 set arm fallback-mode (arm|thumb|auto)
1398 show arm fallback-mode
1399 set arm force-mode (arm|thumb|auto)
1401 These commands control how ARM GDB determines whether instructions
1402 are ARM or Thumb. The default for both settings is auto, which uses
1403 the current CPSR value for instructions without symbols; previous
1404 versions of GDB behaved as if "set arm fallback-mode arm".
1406 set disable-randomization
1407 show disable-randomization
1408 Standalone programs run with the virtual address space randomization enabled
1409 by default on some platforms. This option keeps the addresses stable across
1410 multiple debugging sessions.
1414 Control whether other threads are stopped or not when some thread hits
1419 Requests that asynchronous execution is enabled in the target, if available.
1420 In this case, it's possible to resume target in the background, and interact
1421 with GDB while the target is running. "show target-async" displays the
1422 current state of asynchronous execution of the target.
1424 set target-wide-charset
1425 show target-wide-charset
1426 The target-wide-charset is the name of the character set that GDB
1427 uses when printing characters whose type is wchar_t.
1429 set tcp auto-retry (on|off)
1431 set tcp connect-timeout
1432 show tcp connect-timeout
1433 These commands allow GDB to retry failed TCP connections to a remote stub
1434 with a specified timeout period; this is useful if the stub is launched
1435 in parallel with GDB but may not be ready to accept connections immediately.
1437 set libthread-db-search-path
1438 show libthread-db-search-path
1439 Control list of directories which GDB will search for appropriate
1442 set schedule-multiple (on|off)
1443 show schedule-multiple
1444 Allow GDB to resume all threads of all processes or only threads of
1445 the current process.
1449 Use more aggressive caching for accesses to the stack. This improves
1450 performance of remote debugging (particularly backtraces) without
1451 affecting correctness.
1453 set interactive-mode (on|off|auto)
1454 show interactive-mode
1455 Control whether GDB runs in interactive mode (on) or not (off).
1456 When in interactive mode, GDB waits for the user to answer all
1457 queries. Otherwise, GDB does not wait and assumes the default
1458 answer. When set to auto (the default), GDB determines which
1459 mode to use based on the stdin settings.
1464 For program forks, this is replaced by the new more generic `info
1465 inferiors' command. To list checkpoints, you can still use the
1466 `info checkpoints' command, which was an alias for the `info forks'
1470 Replaced by the new `inferior' command. To switch between
1471 checkpoints, you can still use the `restart' command, which was an
1472 alias for the `fork' command.
1475 This is removed, since some targets don't have a notion of
1476 processes. To switch between processes, you can still use the
1477 `inferior' command using GDB's own inferior number.
1480 For program forks, this is replaced by the new more generic `kill
1481 inferior' command. To delete a checkpoint, you can still use the
1482 `delete checkpoint' command, which was an alias for the `delete
1486 For program forks, this is replaced by the new more generic `detach
1487 inferior' command. To detach a checkpoint, you can still use the
1488 `detach checkpoint' command, which was an alias for the `detach
1491 * New native configurations
1493 x86/x86_64 Darwin i[34567]86-*-darwin*
1495 x86_64 MinGW x86_64-*-mingw*
1499 Lattice Mico32 lm32-*
1500 x86 DICOS i[34567]86-*-dicos*
1501 x86_64 DICOS x86_64-*-dicos*
1504 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1505 (mingw32ce) debugging.
1511 These commands were actually not implemented on any target.
1513 *** Changes in GDB 6.8
1515 * New native configurations
1517 NetBSD/hppa hppa*-*netbsd*
1518 Xtensa GNU/Linux xtensa*-*-linux*
1522 NetBSD/hppa hppa*-*-netbsd*
1523 Xtensa GNU/Lunux xtensa*-*-linux*
1525 * Change in command line behavior -- corefiles vs. process ids.
1527 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1528 attaching to process NUMBER fails, GDB no longer attempts to open a
1529 core file named NUMBER. Attaching to a program using the -c option
1530 is no longer supported. Instead, use the '-p' or '--pid' options.
1532 * GDB can now be built as a native debugger for debugging Windows x86
1533 (mingw32) Portable Executable (PE) programs.
1535 * Pending breakpoints no longer change their number when their address
1538 * GDB now supports breakpoints with multiple locations,
1539 including breakpoints on C++ constructors, inside C++ templates,
1540 and in inlined functions.
1542 * GDB's ability to debug optimized code has been improved. GDB more
1543 accurately identifies function bodies and lexical blocks that occupy
1544 more than one contiguous range of addresses.
1546 * Target descriptions can now describe registers for PowerPC.
1548 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1549 registers on PowerPC targets.
1551 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1552 targets even when the libthread_db library is not available.
1554 * The GDB remote stub, gdbserver, now supports the new file transfer
1555 commands (remote put, remote get, and remote delete).
1557 * The GDB remote stub, gdbserver, now supports run and attach in
1558 extended-remote mode.
1560 * hppa*64*-*-hpux11* target broken
1561 The debugger is unable to start a program and fails with the following
1562 error: "Error trying to get information about dynamic linker".
1563 The gdb-6.7 release is also affected.
1565 * GDB now supports the --enable-targets= configure option to allow
1566 building a single GDB executable that supports multiple remote
1567 target architectures.
1569 * GDB now supports debugging C and C++ programs which use the
1570 Decimal Floating Point extension. In addition, the PowerPC target
1571 now has a set of pseudo-registers to inspect decimal float values
1572 stored in two consecutive float registers.
1574 * The -break-insert MI command can optionally create pending
1577 * Improved support for debugging Ada
1578 Many improvements to the Ada language support have been made. These
1580 - Better support for Ada2005 interface types
1581 - Improved handling of arrays and slices in general
1582 - Better support for Taft-amendment types
1583 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1585 - Improved command completion in Ada
1588 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1593 set print frame-arguments (all|scalars|none)
1594 show print frame-arguments
1595 The value of this variable can be changed to control which argument
1596 values should be printed by the debugger when displaying a frame.
1601 Transfer files to and from a remote target, and delete remote files.
1608 Transfer files to and from a remote target, and delete remote files.
1610 * New remote packets
1617 Open, close, read, write, and delete files on the remote system.
1620 Attach to an existing process on the remote system, in extended-remote
1624 Run a new process on the remote system, in extended-remote mode.
1626 *** Changes in GDB 6.7
1628 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1629 bfd, libiberty and opcodes, as revealed by static analysis donated by
1630 Coverity, Inc. (http://scan.coverity.com).
1632 * When looking up multiply-defined global symbols, GDB will now prefer the
1633 symbol definition in the current shared library if it was built using the
1634 -Bsymbolic linker option.
1636 * When the Text User Interface (TUI) is not configured, GDB will now
1637 recognize the -tui command-line option and print a message that the TUI
1640 * The GDB remote stub, gdbserver, now has lower overhead for high
1641 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1643 * GDB for MIPS targets now autodetects whether a remote target provides
1644 32-bit or 64-bit register values.
1646 * Support for C++ member pointers has been improved.
1648 * GDB now understands XML target descriptions, which specify the
1649 target's overall architecture. GDB can read a description from
1650 a local file or over the remote serial protocol.
1652 * Vectors of single-byte data use a new integer type which is not
1653 automatically displayed as character or string data.
1655 * The /s format now works with the print command. It displays
1656 arrays of single-byte integers and pointers to single-byte integers
1659 * Target descriptions can now describe target-specific registers,
1660 for architectures which have implemented the support (currently
1661 only ARM, M68K, and MIPS).
1663 * GDB and the GDB remote stub, gdbserver, now support the XScale
1666 * The GDB remote stub, gdbserver, has been updated to support
1667 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1668 has been rewritten to use the standard GDB remote protocol.
1670 * GDB can now step into C++ functions which are called through thunks.
1672 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1674 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1675 layout. It also supports a TextSeg= and DataSeg= response when only
1676 segment base addresses (rather than offsets) are available.
1678 * The /i format now outputs any trailing branch delay slot instructions
1679 immediately following the last instruction within the count specified.
1681 * The GDB remote protocol "T" stop reply packet now supports a
1682 "library" response. Combined with the new "qXfer:libraries:read"
1683 packet, this response allows GDB to debug shared libraries on targets
1684 where the operating system manages the list of loaded libraries (e.g.
1685 Windows and SymbianOS).
1687 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1688 (DLLs) on Windows and Windows CE targets.
1690 * GDB now supports a faster verification that a .debug file matches its binary
1691 according to its build-id signature, if the signature is present.
1697 Enable or disable hardware flow control (RTS/CTS) on the serial port
1698 when debugging using remote targets.
1700 set mem inaccessible-by-default
1701 show mem inaccessible-by-default
1702 If the target supplies a memory map, for instance via the remote
1703 protocol's "qXfer:memory-map:read" packet, setting this variable
1704 prevents GDB from accessing memory outside the memory map. This
1705 is useful for targets with memory mapped registers or which react
1706 badly to accesses of unmapped address space.
1708 set breakpoint auto-hw
1709 show breakpoint auto-hw
1710 If the target supplies a memory map, for instance via the remote
1711 protocol's "qXfer:memory-map:read" packet, setting this variable
1712 lets GDB use hardware breakpoints automatically for memory regions
1713 where it can not use software breakpoints. This covers both the
1714 "break" command and internal breakpoints used for other commands
1715 including "next" and "finish".
1718 catch exception unhandled
1719 Stop the program execution when Ada exceptions are raised.
1722 Stop the program execution when an Ada assertion failed.
1726 Set an alternate system root for target files. This is a more
1727 general version of "set solib-absolute-prefix", which is now
1728 an alias to "set sysroot".
1731 Provide extended SPU facility status information. This set of
1732 commands is available only when debugging the Cell/B.E. SPU
1735 * New native configurations
1737 OpenBSD/sh sh*-*openbsd*
1740 unset tdesc filename
1742 Use the specified local file as an XML target description, and do
1743 not query the target for its built-in description.
1747 OpenBSD/sh sh*-*-openbsd*
1748 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1749 Toshiba Media Processor mep-elf
1751 * New remote packets
1754 Ignore the specified signals; pass them directly to the debugged program
1755 without stopping other threads or reporting them to GDB.
1757 qXfer:features:read:
1758 Read an XML target description from the target, which describes its
1763 Read or write contents of an spufs file on the target system. These
1764 packets are available only on the Cell/B.E. SPU architecture.
1766 qXfer:libraries:read:
1767 Report the loaded shared libraries. Combined with new "T" packet
1768 response, this packet allows GDB to debug shared libraries on
1769 targets where the operating system manages the list of loaded
1770 libraries (e.g. Windows and SymbianOS).
1774 Support for these obsolete configurations has been removed.
1782 i[34567]86-*-lynxos*
1783 i[34567]86-*-netware*
1784 i[34567]86-*-sco3.2v5*
1785 i[34567]86-*-sco3.2v4*
1787 i[34567]86-*-sysv4.2*
1790 i[34567]86-*-unixware2*
1791 i[34567]86-*-unixware*
1800 * Other removed features
1807 Various m68k-only ROM monitors.
1814 Various Renesas ROM monitors and debugging interfaces for SH and
1819 Support for a Macraigor serial interface to on-chip debugging.
1820 GDB does not directly support the newer parallel or USB
1825 A debug information format. The predecessor to DWARF 2 and
1826 DWARF 3, which are still supported.
1828 Support for the HP aCC compiler on HP-UX/PA-RISC
1830 SOM-encapsulated symbolic debugging information, automatic
1831 invocation of pxdb, and the aCC custom C++ ABI. This does not
1832 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1833 with aCC can still be debugged on an assembly level.
1835 MIPS ".pdr" sections
1837 A MIPS-specific format used to describe stack frame layout
1838 in debugging information.
1842 GDB could work with an older version of Guile to debug
1843 the interpreter and Scheme programs running in it.
1845 set mips stack-arg-size
1846 set mips saved-gpreg-size
1848 Use "set mips abi" to control parameter passing for MIPS.
1850 *** Changes in GDB 6.6
1855 Cell Broadband Engine SPU spu-elf
1857 * GDB can now be configured as a cross-debugger targeting native Windows
1858 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1859 running on a Windows system over TCP/IP to debug Windows programs.
1861 * The GDB remote stub, gdbserver, has been updated to support Windows and
1862 Cygwin debugging. Both single-threaded and multi-threaded programs are
1865 * The "set trust-readonly-sections" command works again. This command was
1866 broken in GDB 6.3, 6.4, and 6.5.
1868 * The "load" command now supports writing to flash memory, if the remote
1869 stub provides the required support.
1871 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1872 longer requires symbolic debug information (e.g. DWARF-2).
1877 unset substitute-path
1878 show substitute-path
1879 Manage a list of substitution rules that GDB uses to rewrite the name
1880 of the directories where the sources are located. This can be useful
1881 for instance when the sources were moved to a different location
1882 between compilation and debugging.
1886 Print each CLI command as it is executed. Each command is prefixed with
1887 a number of `+' symbols representing the nesting depth.
1888 The source command now has a `-v' option to enable the same feature.
1892 The ARM Demon monitor support (RDP protocol, "target rdp").
1894 Kernel Object Display, an embedded debugging feature which only worked with
1895 an obsolete version of Cisco IOS.
1897 The 'set download-write-size' and 'show download-write-size' commands.
1899 * New remote packets
1902 Tell a stub about GDB client features, and request remote target features.
1903 The first feature implemented is PacketSize, which allows the target to
1904 specify the size of packets it can handle - to minimize the number of
1905 packets required and improve performance when connected to a remote
1909 Fetch an OS auxilliary vector from the remote stub. This packet is a
1910 more efficient replacement for qPart:auxv:read.
1912 qXfer:memory-map:read:
1913 Fetch a memory map from the remote stub, including information about
1914 RAM, ROM, and flash memory devices.
1919 Erase and program a flash memory device.
1921 * Removed remote packets
1924 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1925 used it, and only gdbserver implemented it.
1927 *** Changes in GDB 6.5
1931 Renesas M32C/M16C m32c-elf
1933 Morpho Technologies ms1 ms1-elf
1937 init-if-undefined Initialize a convenience variable, but
1938 only if it doesn't already have a value.
1940 The following commands are presently only implemented for native GNU/Linux:
1942 checkpoint Save a snapshot of the program state.
1944 restart <n> Return the program state to a
1945 previously saved state.
1947 info checkpoints List currently saved checkpoints.
1949 delete-checkpoint <n> Delete a previously saved checkpoint.
1951 set|show detach-on-fork Tell gdb whether to detach from a newly
1952 forked process, or to keep debugging it.
1954 info forks List forks of the user program that
1955 are available to be debugged.
1957 fork <n> Switch to debugging one of several
1958 forks of the user program that are
1959 available to be debugged.
1961 delete-fork <n> Delete a fork from the list of forks
1962 that are available to be debugged (and
1963 kill the forked process).
1965 detach-fork <n> Delete a fork from the list of forks
1966 that are available to be debugged (and
1967 allow the process to continue).
1971 Morpho Technologies ms2 ms1-elf
1973 * Improved Windows host support
1975 GDB now builds as a cross debugger hosted on i686-mingw32, including
1976 native console support, and remote communications using either
1977 network sockets or serial ports.
1979 * Improved Modula-2 language support
1981 GDB can now print most types in the Modula-2 syntax. This includes:
1982 basic types, set types, record types, enumerated types, range types,
1983 pointer types and ARRAY types. Procedure var parameters are correctly
1984 printed and hexadecimal addresses and character constants are also
1985 written in the Modula-2 syntax. Best results can be obtained by using
1986 GNU Modula-2 together with the -gdwarf-2 command line option.
1990 The ARM rdi-share module.
1992 The Netware NLM debug server.
1994 *** Changes in GDB 6.4
1996 * New native configurations
1998 OpenBSD/arm arm*-*-openbsd*
1999 OpenBSD/mips64 mips64-*-openbsd*
2003 Morpho Technologies ms1 ms1-elf
2005 * New command line options
2007 --batch-silent As for --batch, but totally silent.
2008 --return-child-result The debugger will exist with the same value
2009 the child (debugged) program exited with.
2010 --eval-command COMMAND, -ex COMMAND
2011 Execute a single GDB CLI command. This may be
2012 specified multiple times and in conjunction
2013 with the --command (-x) option.
2015 * Deprecated commands removed
2017 The following commands, that were deprecated in 2000, have been
2021 set|show arm disassembly-flavor set|show arm disassembler
2022 othernames set arm disassembler
2023 set|show remotedebug set|show debug remote
2024 set|show archdebug set|show debug arch
2025 set|show eventdebug set|show debug event
2028 * New BSD user-level threads support
2030 It is now possible to debug programs using the user-level threads
2031 library on OpenBSD and FreeBSD. Currently supported (target)
2034 FreeBSD/amd64 x86_64-*-freebsd*
2035 FreeBSD/i386 i386-*-freebsd*
2036 OpenBSD/i386 i386-*-openbsd*
2038 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2039 are not yet supported.
2041 * New support for Matsushita MN10300 w/sim added
2042 (Work in progress). mn10300-elf.
2044 * REMOVED configurations and files
2046 VxWorks and the XDR protocol *-*-vxworks
2047 Motorola MCORE mcore-*-*
2048 National Semiconductor NS32000 ns32k-*-*
2050 * New "set print array-indexes" command
2052 After turning this setting "on", GDB prints the index of each element
2053 when displaying arrays. The default is "off" to preserve the previous
2056 * VAX floating point support
2058 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2060 * User-defined command support
2062 In addition to using $arg0..$arg9 for argument passing, it is now possible
2063 to use $argc to determine now many arguments have been passed. See the
2064 section on user-defined commands in the user manual for more information.
2066 *** Changes in GDB 6.3:
2068 * New command line option
2070 GDB now accepts -l followed by a number to set the timeout for remote
2073 * GDB works with GCC -feliminate-dwarf2-dups
2075 GDB now supports a more compact representation of DWARF-2 debug
2076 information using DW_FORM_ref_addr references. These are produced
2077 by GCC with the option -feliminate-dwarf2-dups and also by some
2078 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2079 to use -feliminate-dwarf2-dups.
2081 * Internationalization
2083 When supported by the host system, GDB will be built with
2084 internationalization (libintl). The task of marking up the sources is
2085 continued, we're looking forward to our first translation.
2089 Initial support for debugging programs compiled with the GNAT
2090 implementation of the Ada programming language has been integrated
2091 into GDB. In this release, support is limited to expression evaluation.
2093 * New native configurations
2095 GNU/Linux/m32r m32r-*-linux-gnu
2099 GDB's remote protocol now includes support for the 'p' packet. This
2100 packet is used to fetch individual registers from a remote inferior.
2102 * END-OF-LIFE registers[] compatibility module
2104 GDB's internal register infrastructure has been completely rewritten.
2105 The new infrastructure making possible the implementation of key new
2106 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2109 GDB 6.3 will be the last release to include the the registers[]
2110 compatibility module that allowed out-of-date configurations to
2111 continue to work. This change directly impacts the following
2121 powerpc bdm protocol
2123 Unless there is activity to revive these configurations, they will be
2124 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2126 * OBSOLETE configurations and files
2128 Configurations that have been declared obsolete in this release have
2129 been commented out. Unless there is activity to revive these
2130 configurations, the next release of GDB will have their sources
2131 permanently REMOVED.
2140 *** Changes in GDB 6.2.1:
2142 * MIPS `break main; run' gave an heuristic-fence-post warning
2144 When attempting to run even a simple program, a warning about
2145 heuristic-fence-post being hit would be reported. This problem has
2148 * MIPS IRIX 'long double' crashed GDB
2150 When examining a long double variable, GDB would get a segmentation
2151 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2152 IRIX long double values).
2156 A bug in the VAX stack code was causing problems with the "next"
2157 command. This problem has been fixed.
2159 *** Changes in GDB 6.2:
2161 * Fix for ``many threads''
2163 On GNU/Linux systems that use the NPTL threads library, a program
2164 rapidly creating and deleting threads would confuse GDB leading to the
2167 ptrace: No such process.
2168 thread_db_get_info: cannot get thread info: generic error
2170 This problem has been fixed.
2172 * "-async" and "-noasync" options removed.
2174 Support for the broken "-noasync" option has been removed (it caused
2177 * New ``start'' command.
2179 This command runs the program until the begining of the main procedure.
2181 * New BSD Kernel Data Access Library (libkvm) interface
2183 Using ``target kvm'' it is now possible to debug kernel core dumps and
2184 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2185 platforms. Currently supported (native-only) configurations are:
2187 FreeBSD/amd64 x86_64-*-freebsd*
2188 FreeBSD/i386 i?86-*-freebsd*
2189 NetBSD/i386 i?86-*-netbsd*
2190 NetBSD/m68k m68*-*-netbsd*
2191 NetBSD/sparc sparc-*-netbsd*
2192 OpenBSD/amd64 x86_64-*-openbsd*
2193 OpenBSD/i386 i?86-*-openbsd*
2194 OpenBSD/m68k m68*-openbsd*
2195 OpenBSD/sparc sparc-*-openbsd*
2197 * Signal trampoline code overhauled
2199 Many generic problems with GDB's signal handling code have been fixed.
2200 These include: backtraces through non-contiguous stacks; recognition
2201 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2202 call; backtrace through a signal trampoline; step into and out of
2203 signal handlers; and single-stepping in the signal trampoline.
2205 Please note that kernel bugs are a limiting factor here. These
2206 features have been shown to work on an s390 GNU/Linux system that
2207 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2209 * Cygwin support for DWARF 2 added.
2211 * New native configurations
2213 GNU/Linux/hppa hppa*-*-linux*
2214 OpenBSD/hppa hppa*-*-openbsd*
2215 OpenBSD/m68k m68*-*-openbsd*
2216 OpenBSD/m88k m88*-*-openbsd*
2217 OpenBSD/powerpc powerpc-*-openbsd*
2218 NetBSD/vax vax-*-netbsd*
2219 OpenBSD/vax vax-*-openbsd*
2221 * END-OF-LIFE frame compatibility module
2223 GDB's internal frame infrastructure has been completely rewritten.
2224 The new infrastructure making it possible to support key new features
2225 including DWARF 2 Call Frame Information. To aid in the task of
2226 migrating old configurations to this new infrastructure, a
2227 compatibility module, that allowed old configurations to continue to
2228 work, was also included.
2230 GDB 6.2 will be the last release to include this frame compatibility
2231 module. This change directly impacts the following configurations:
2241 Unless there is activity to revive these configurations, they will be
2242 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2244 * REMOVED configurations and files
2246 Sun 3, running SunOS 3 m68*-*-sunos3*
2247 Sun 3, running SunOS 4 m68*-*-sunos4*
2248 Sun 2, running SunOS 3 m68000-*-sunos3*
2249 Sun 2, running SunOS 4 m68000-*-sunos4*
2250 Motorola 680x0 running LynxOS m68*-*-lynxos*
2251 AT&T 3b1/Unix pc m68*-att-*
2252 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2253 decstation mips-dec-* mips-little-*
2254 riscos mips-*-riscos* mips-*-sysv*
2255 sonymips mips-sony-*
2256 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2258 *** Changes in GDB 6.1.1:
2260 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2262 The TUI (Text-mode User Interface) is now built as part of a default
2263 GDB configuration. It is enabled by either selecting the TUI with the
2264 command line option "-i=tui" or by running the separate "gdbtui"
2265 program. For more information on the TUI, see the manual "Debugging
2268 * Pending breakpoint support (also included in GDB 6.1)
2270 Support has been added to allow you to specify breakpoints in shared
2271 libraries that have not yet been loaded. If a breakpoint location
2272 cannot be found, and the "breakpoint pending" option is set to auto,
2273 GDB queries you if you wish to make the breakpoint pending on a future
2274 shared-library load. If and when GDB resolves the breakpoint symbol,
2275 the pending breakpoint is removed as one or more regular breakpoints
2278 Pending breakpoints are very useful for GCJ Java debugging.
2280 * Fixed ISO-C build problems
2282 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2283 non ISO-C code that stopped them being built using a more strict ISO-C
2284 compiler (e.g., IBM's C compiler).
2286 * Fixed build problem on IRIX 5
2288 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2289 wasn't able to compile compile on an IRIX 5 system.
2291 * Added execute permission to gdb/gdbserver/configure
2293 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2294 permission. This bug would cause configure to fail on a number of
2295 systems (Solaris, IRIX). Ref: server/519.
2297 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2299 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2300 has been updated to use constant array sizes.
2302 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2304 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2305 its generated DWARF Call Frame Info. This encoding was causing GDB to
2306 panic, that panic has been fixed. Ref: gdb/1628.
2308 * Fixed a problem when examining parameters in shared library code.
2310 When examining parameters in optimized shared library code generated
2311 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2312 not available''. GDB now correctly displays the variable's value.
2314 *** Changes in GDB 6.1:
2316 * Removed --with-mmalloc
2318 Support for the mmalloc memory manager has been removed, as it
2319 conflicted with the internal gdb byte cache.
2321 * Changes in AMD64 configurations
2323 The AMD64 target now includes the %cs and %ss registers. As a result
2324 the AMD64 remote protocol has changed; this affects the floating-point
2325 and SSE registers. If you rely on those registers for your debugging,
2326 you should upgrade gdbserver on the remote side.
2328 * Revised SPARC target
2330 The SPARC target has been completely revised, incorporating the
2331 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2332 support for LynxOS and SunOS 4 has been dropped. Calling functions
2333 from within GDB on operating systems with a non-executable stack
2334 (Solaris, OpenBSD) now works.
2338 GDB has a new C++ demangler which does a better job on the mangled
2339 names generated by current versions of g++. It also runs faster, so
2340 with this and other changes gdb should now start faster on large C++
2343 * DWARF 2 Location Expressions
2345 GDB support for location expressions has been extended to support function
2346 arguments and frame bases. Older versions of GDB could crash when they
2349 * C++ nested types and namespaces
2351 GDB's support for nested types and namespaces in C++ has been
2352 improved, especially if you use the DWARF 2 debugging format. (This
2353 is the default for recent versions of GCC on most platforms.)
2354 Specifically, if you have a class "Inner" defined within a class or
2355 namespace "Outer", then GDB realizes that the class's name is
2356 "Outer::Inner", not simply "Inner". This should greatly reduce the
2357 frequency of complaints about not finding RTTI symbols. In addition,
2358 if you are stopped at inside of a function defined within a namespace,
2359 GDB modifies its name lookup accordingly.
2361 * New native configurations
2363 NetBSD/amd64 x86_64-*-netbsd*
2364 OpenBSD/amd64 x86_64-*-openbsd*
2365 OpenBSD/alpha alpha*-*-openbsd*
2366 OpenBSD/sparc sparc-*-openbsd*
2367 OpenBSD/sparc64 sparc64-*-openbsd*
2369 * New debugging protocols
2371 M32R with SDI protocol m32r-*-elf*
2373 * "set prompt-escape-char" command deleted.
2375 The command "set prompt-escape-char" has been deleted. This command,
2376 and its very obscure effet on GDB's prompt, was never documented,
2377 tested, nor mentioned in the NEWS file.
2379 * OBSOLETE configurations and files
2381 Configurations that have been declared obsolete in this release have
2382 been commented out. Unless there is activity to revive these
2383 configurations, the next release of GDB will have their sources
2384 permanently REMOVED.
2386 Sun 3, running SunOS 3 m68*-*-sunos3*
2387 Sun 3, running SunOS 4 m68*-*-sunos4*
2388 Sun 2, running SunOS 3 m68000-*-sunos3*
2389 Sun 2, running SunOS 4 m68000-*-sunos4*
2390 Motorola 680x0 running LynxOS m68*-*-lynxos*
2391 AT&T 3b1/Unix pc m68*-att-*
2392 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2393 decstation mips-dec-* mips-little-*
2394 riscos mips-*-riscos* mips-*-sysv*
2395 sonymips mips-sony-*
2396 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2398 * REMOVED configurations and files
2400 SGI Irix-4.x mips-sgi-irix4 or iris4
2401 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2402 Z8000 simulator z8k-zilog-none or z8ksim
2403 Matsushita MN10200 w/simulator mn10200-*-*
2404 H8/500 simulator h8500-hitachi-hms or h8500hms
2405 HP/PA running BSD hppa*-*-bsd*
2406 HP/PA running OSF/1 hppa*-*-osf*
2407 HP/PA Pro target hppa*-*-pro*
2408 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2409 386BSD i[3456]86-*-bsd*
2410 Sequent family i[3456]86-sequent-sysv4*
2411 i[3456]86-sequent-sysv*
2412 i[3456]86-sequent-bsd*
2413 SPARC running LynxOS sparc-*-lynxos*
2414 SPARC running SunOS 4 sparc-*-sunos4*
2415 Tsqware Sparclet sparclet-*-*
2416 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2418 *** Changes in GDB 6.0:
2422 Support for debugging the Objective-C programming language has been
2423 integrated into GDB.
2425 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2427 DWARF 2's Call Frame Information makes available compiler generated
2428 information that more exactly describes the program's run-time stack.
2429 By using this information, GDB is able to provide more robust stack
2432 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2433 have been updated to use a new backtrace mechanism which includes
2434 DWARF 2 CFI support.
2438 GDB's remote protocol has been extended to include support for hosted
2439 file I/O (where the remote target uses GDB's file system). See GDB's
2440 remote protocol documentation for details.
2442 * All targets using the new architecture framework.
2444 All of GDB's targets have been updated to use the new internal
2445 architecture framework. The way is now open for future GDB releases
2446 to include cross-architecture native debugging support (i386 on amd64,
2449 * GNU/Linux's Thread Local Storage (TLS)
2451 GDB now includes support for for the GNU/Linux implementation of
2452 per-thread variables.
2454 * GNU/Linux's Native POSIX Thread Library (NPTL)
2456 GDB's thread code has been updated to work with either the new
2457 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2459 * Separate debug info.
2461 GDB, in conjunction with BINUTILS, now supports a mechanism for
2462 automatically loading debug information from a separate file. Instead
2463 of shipping full debug and non-debug versions of system libraries,
2464 system integrators can now instead ship just the stripped libraries
2465 and optional debug files.
2467 * DWARF 2 Location Expressions
2469 DWARF 2 Location Expressions allow the compiler to more completely
2470 describe the location of variables (even in optimized code) to the
2473 GDB now includes preliminary support for location expressions (support
2474 for DW_OP_piece is still missing).
2478 A number of long standing bugs that caused GDB to die while starting a
2479 Java application have been fixed. GDB's Java support is now
2480 considered "useable".
2482 * GNU/Linux support for fork, vfork, and exec.
2484 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2485 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2488 * GDB supports logging output to a file
2490 There are two new commands, "set logging" and "show logging", which can be
2491 used to capture GDB's output to a file.
2493 * The meaning of "detach" has changed for gdbserver
2495 The "detach" command will now resume the application, as documented. To
2496 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2499 * d10v, m68hc11 `regs' command deprecated
2501 The `info registers' command has been updated so that it displays the
2502 registers using a format identical to the old `regs' command.
2506 A new command, "maint set profile on/off", has been added. This command can
2507 be used to enable or disable profiling while running GDB, to profile a
2508 session or a set of commands. In addition there is a new configure switch,
2509 "--enable-profiling", which will cause GDB to be compiled with profiling
2510 data, for more informative profiling results.
2512 * Default MI syntax changed to "mi2".
2514 The default MI (machine interface) syntax, enabled by the command line
2515 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2516 "mi1", can be enabled by specifying the option "-i=mi1".
2518 Support for the original "mi0" syntax (included in GDB 5.0) has been
2521 Fix for gdb/192: removed extraneous space when displaying frame level.
2522 Fix for gdb/672: update changelist is now output in mi list format.
2523 Fix for gdb/702: a -var-assign that updates the value now shows up
2524 in a subsequent -var-update.
2526 * New native configurations.
2528 FreeBSD/amd64 x86_64-*-freebsd*
2530 * Multi-arched targets.
2532 HP/PA HPUX11 hppa*-*-hpux*
2533 Renesas M32R/D w/simulator m32r-*-elf*
2535 * OBSOLETE configurations and files
2537 Configurations that have been declared obsolete in this release have
2538 been commented out. Unless there is activity to revive these
2539 configurations, the next release of GDB will have their sources
2540 permanently REMOVED.
2542 Z8000 simulator z8k-zilog-none or z8ksim
2543 Matsushita MN10200 w/simulator mn10200-*-*
2544 H8/500 simulator h8500-hitachi-hms or h8500hms
2545 HP/PA running BSD hppa*-*-bsd*
2546 HP/PA running OSF/1 hppa*-*-osf*
2547 HP/PA Pro target hppa*-*-pro*
2548 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2549 Sequent family i[3456]86-sequent-sysv4*
2550 i[3456]86-sequent-sysv*
2551 i[3456]86-sequent-bsd*
2552 Tsqware Sparclet sparclet-*-*
2553 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2555 * REMOVED configurations and files
2558 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2559 IBM AIX PS/2 i[3456]86-*-aix
2560 i386 running Mach 3.0 i[3456]86-*-mach3*
2561 i386 running Mach i[3456]86-*-mach*
2562 i386 running OSF/1 i[3456]86-*osf1mk*
2563 HP/Apollo 68k Family m68*-apollo*-sysv*,
2565 m68*-hp-bsd*, m68*-hp-hpux*
2566 Argonaut Risc Chip (ARC) arc-*-*
2567 Mitsubishi D30V d30v-*-*
2568 Fujitsu FR30 fr30-*-elf*
2569 OS/9000 i[34]86-*-os9k
2570 I960 with MON960 i960-*-coff
2572 * MIPS $fp behavior changed
2574 The convenience variable $fp, for the MIPS, now consistently returns
2575 the address of the current frame's base. Previously, depending on the
2576 context, $fp could refer to either $sp or the current frame's base
2577 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2578 The GNU Source-Level Debugger''.
2580 *** Changes in GDB 5.3:
2582 * GNU/Linux shared library multi-threaded performance improved.
2584 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2585 `/proc', in preference to `ptrace' for memory reads. This may result
2586 in an improvement in the start-up time of multi-threaded, shared
2587 library applications when run under GDB. One GDB user writes: ``loads
2588 shared libs like mad''.
2590 * ``gdbserver'' now supports multi-threaded applications on some targets
2592 Support for debugging multi-threaded applications which use
2593 the GNU/Linux LinuxThreads package has been added for
2594 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2595 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2597 * GDB now supports C/C++ preprocessor macros.
2599 GDB now expands preprocessor macro invocations in C/C++ expressions,
2600 and provides various commands for showing macro definitions and how
2603 The new command `macro expand EXPRESSION' expands any macro
2604 invocations in expression, and shows the result.
2606 The new command `show macro MACRO-NAME' shows the definition of the
2607 macro named MACRO-NAME, and where it was defined.
2609 Most compilers don't include information about macros in the debugging
2610 information by default. In GCC 3.1, for example, you need to compile
2611 your program with the options `-gdwarf-2 -g3'. If the macro
2612 information is present in the executable, GDB will read it.
2614 * Multi-arched targets.
2616 DEC Alpha (partial) alpha*-*-*
2617 DEC VAX (partial) vax-*-*
2619 National Semiconductor NS32000 (partial) ns32k-*-*
2620 Motorola 68000 (partial) m68k-*-*
2621 Motorola MCORE mcore-*-*
2625 Fujitsu FRV architecture added by Red Hat frv*-*-*
2628 * New native configurations
2630 Alpha NetBSD alpha*-*-netbsd*
2631 SH NetBSD sh*-*-netbsdelf*
2632 MIPS NetBSD mips*-*-netbsd*
2633 UltraSPARC NetBSD sparc64-*-netbsd*
2635 * OBSOLETE configurations and files
2637 Configurations that have been declared obsolete in this release have
2638 been commented out. Unless there is activity to revive these
2639 configurations, the next release of GDB will have their sources
2640 permanently REMOVED.
2642 Mitsubishi D30V d30v-*-*
2643 OS/9000 i[34]86-*-os9k
2644 IBM AIX PS/2 i[3456]86-*-aix
2645 Fujitsu FR30 fr30-*-elf*
2646 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2647 Argonaut Risc Chip (ARC) arc-*-*
2648 i386 running Mach 3.0 i[3456]86-*-mach3*
2649 i386 running Mach i[3456]86-*-mach*
2650 i386 running OSF/1 i[3456]86-*osf1mk*
2651 HP/Apollo 68k Family m68*-apollo*-sysv*,
2653 m68*-hp-bsd*, m68*-hp-hpux*
2654 I960 with MON960 i960-*-coff
2656 * OBSOLETE languages
2658 CHILL, a Pascal like language used by telecommunications companies.
2660 * REMOVED configurations and files
2662 AMD 29k family via UDI a29k-amd-udi, udi29k
2663 A29K VxWorks a29k-*-vxworks
2664 AMD 29000 embedded, using EBMON a29k-none-none
2665 AMD 29000 embedded with COFF a29k-none-coff
2666 AMD 29000 embedded with a.out a29k-none-aout
2668 testsuite/gdb.hp/gdb.threads-hp/ directory
2670 * New command "set max-user-call-depth <nnn>"
2672 This command allows the user to limit the call depth of user-defined
2673 commands. The default is 1024.
2675 * Changes in FreeBSD/i386 native debugging.
2677 Support for the "generate-core-file" has been added.
2679 * New commands "dump", "append", and "restore".
2681 These commands allow data to be copied from target memory
2682 to a bfd-format or binary file (dump and append), and back
2683 from a file into memory (restore).
2685 * Improved "next/step" support on multi-processor Alpha Tru64.
2687 The previous single-step mechanism could cause unpredictable problems,
2688 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2689 of a software single-step mechanism prevents this.
2691 *** Changes in GDB 5.2.1:
2699 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2700 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2701 Fix, by Joel Brobecker imported from mainline.
2703 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2704 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2705 Fix, by Fred Fish, imported from mainline.
2707 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2708 Surprisingly enough, it works now.
2709 By Michal Ludvig, imported from mainline.
2711 i386 hardware watchpoint support:
2712 avoid misses on second run for some targets.
2713 By Pierre Muller, imported from mainline.
2715 *** Changes in GDB 5.2:
2717 * New command "set trust-readonly-sections on[off]".
2719 This command is a hint that tells gdb that read-only sections
2720 really are read-only (ie. that their contents will not change).
2721 In this mode, gdb will go to the object file rather than the
2722 target to read memory from read-only sections (such as ".text").
2723 This can be a significant performance improvement on some
2724 (notably embedded) targets.
2726 * New command "generate-core-file" (or "gcore").
2728 This new gdb command allows the user to drop a core file of the child
2729 process state at any time. So far it's been implemented only for
2730 GNU/Linux and Solaris, but should be relatively easily ported to other
2731 hosts. Argument is core file name (defaults to core.<pid>).
2733 * New command line option
2735 GDB now accepts --pid or -p followed by a process id.
2737 * Change in command line behavior -- corefiles vs. process ids.
2739 There is a subtle behavior in the way in which GDB handles
2740 command line arguments. The first non-flag argument is always
2741 a program to debug, but the second non-flag argument may either
2742 be a corefile or a process id. Previously, GDB would attempt to
2743 open the second argument as a corefile, and if that failed, would
2744 issue a superfluous error message and then attempt to attach it as
2745 a process. Now, if the second argument begins with a non-digit,
2746 it will be treated as a corefile. If it begins with a digit,
2747 GDB will attempt to attach it as a process, and if no such process
2748 is found, will then attempt to open it as a corefile.
2750 * Changes in ARM configurations.
2752 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2753 configuration is fully multi-arch.
2755 * New native configurations
2757 ARM NetBSD arm*-*-netbsd*
2758 x86 OpenBSD i[3456]86-*-openbsd*
2759 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2760 Sparc64 running FreeBSD sparc64-*-freebsd*
2764 Sanyo XStormy16 xstormy16-elf
2766 * OBSOLETE configurations and files
2768 Configurations that have been declared obsolete in this release have
2769 been commented out. Unless there is activity to revive these
2770 configurations, the next release of GDB will have their sources
2771 permanently REMOVED.
2773 AMD 29k family via UDI a29k-amd-udi, udi29k
2774 A29K VxWorks a29k-*-vxworks
2775 AMD 29000 embedded, using EBMON a29k-none-none
2776 AMD 29000 embedded with COFF a29k-none-coff
2777 AMD 29000 embedded with a.out a29k-none-aout
2779 testsuite/gdb.hp/gdb.threads-hp/ directory
2781 * REMOVED configurations and files
2783 TI TMS320C80 tic80-*-*
2785 PowerPC Solaris powerpcle-*-solaris*
2786 PowerPC Windows NT powerpcle-*-cygwin32
2787 PowerPC Netware powerpc-*-netware*
2788 Harris/CXUX m88k m88*-harris-cxux*
2789 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2790 ns32k-utek-sysv* ns32k-utek-*
2791 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2792 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2793 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2794 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2795 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2797 * Changes to command line processing
2799 The new `--args' feature can be used to specify command-line arguments
2800 for the inferior from gdb's command line.
2802 * Changes to key bindings
2804 There is a new `operate-and-get-next' function bound to `C-o'.
2806 *** Changes in GDB 5.1.1
2808 Fix compile problem on DJGPP.
2810 Fix a problem with floating-point registers on the i386 being
2813 Fix to stop GDB crashing on .debug_str debug info.
2815 Numerous documentation fixes.
2817 Numerous testsuite fixes.
2819 *** Changes in GDB 5.1:
2821 * New native configurations
2823 Alpha FreeBSD alpha*-*-freebsd*
2824 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2825 MIPS GNU/Linux mips*-*-linux*
2826 MIPS SGI Irix 6.x mips*-sgi-irix6*
2827 ia64 AIX ia64-*-aix*
2828 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2832 Motorola 68HC11 and 68HC12 m68hc11-elf
2834 UltraSparc running GNU/Linux sparc64-*-linux*
2836 * OBSOLETE configurations and files
2838 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2839 Harris/CXUX m88k m88*-harris-cxux*
2840 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2841 ns32k-utek-sysv* ns32k-utek-*
2842 TI TMS320C80 tic80-*-*
2844 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2845 PowerPC Solaris powerpcle-*-solaris*
2846 PowerPC Windows NT powerpcle-*-cygwin32
2847 PowerPC Netware powerpc-*-netware*
2848 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2849 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2850 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2851 Apple Macintosh (MPW) host N/A
2853 stuff.c (Program to stuff files into a specially prepared space in kdb)
2854 kdb-start.c (Main loop for the standalone kernel debugger)
2856 Configurations that have been declared obsolete in this release have
2857 been commented out. Unless there is activity to revive these
2858 configurations, the next release of GDB will have their sources
2859 permanently REMOVED.
2861 * REMOVED configurations and files
2863 Altos 3068 m68*-altos-*
2864 Convex c1-*-*, c2-*-*
2866 ARM RISCix arm-*-* (as host)
2870 * GDB has been converted to ISO C.
2872 GDB's source code has been converted to ISO C. In particular, the
2873 sources are fully protoized, and rely on standard headers being
2878 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2880 * The MI enabled by default.
2882 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2883 revised and enabled by default. Packages which use GDB as a debugging
2884 engine behind a UI or another front end are encouraged to switch to
2885 using the GDB/MI interface, instead of the old annotations interface
2886 which is now deprecated.
2888 * Support for debugging Pascal programs.
2890 GDB now includes support for debugging Pascal programs. The following
2891 main features are supported:
2893 - Pascal-specific data types such as sets;
2895 - automatic recognition of Pascal sources based on file-name
2898 - Pascal-style display of data types, variables, and functions;
2900 - a Pascal expression parser.
2902 However, some important features are not yet supported.
2904 - Pascal string operations are not supported at all;
2906 - there are some problems with boolean types;
2908 - Pascal type hexadecimal constants are not supported
2909 because they conflict with the internal variables format;
2911 - support for Pascal objects and classes is not full yet;
2913 - unlike Pascal, GDB is case-sensitive for symbol names.
2915 * Changes in completion.
2917 Commands such as `shell', `run' and `set args', which pass arguments
2918 to inferior programs, now complete on file names, similar to what
2919 users expect at the shell prompt.
2921 Commands which accept locations, such as `disassemble', `print',
2922 `breakpoint', `until', etc. now complete on filenames as well as
2923 program symbols. Thus, if you type "break foob TAB", and the source
2924 files linked into the programs include `foobar.c', that file name will
2925 be one of the candidates for completion. However, file names are not
2926 considered for completion after you typed a colon that delimits a file
2927 name from a name of a function in that file, as in "break foo.c:bar".
2929 `set demangle-style' completes on available demangling styles.
2931 * New platform-independent commands:
2933 It is now possible to define a post-hook for a command as well as a
2934 hook that runs before the command. For more details, see the
2935 documentation of `hookpost' in the GDB manual.
2937 * Changes in GNU/Linux native debugging.
2939 Support for debugging multi-threaded programs has been completely
2940 revised for all platforms except m68k and sparc. You can now debug as
2941 many threads as your system allows you to have.
2943 Attach/detach is supported for multi-threaded programs.
2945 Support for SSE registers was added for x86. This doesn't work for
2946 multi-threaded programs though.
2948 * Changes in MIPS configurations.
2950 Multi-arch support is enabled for all MIPS configurations.
2952 GDB can now be built as native debugger on SGI Irix 6.x systems for
2953 debugging n32 executables. (Debugging 64-bit executables is not yet
2956 * Unified support for hardware watchpoints in all x86 configurations.
2958 Most (if not all) native x86 configurations support hardware-assisted
2959 breakpoints and watchpoints in a unified manner. This support
2960 implements debug register sharing between watchpoints, which allows to
2961 put a virtually infinite number of watchpoints on the same address,
2962 and also supports watching regions up to 16 bytes with several debug
2965 The new maintenance command `maintenance show-debug-regs' toggles
2966 debugging print-outs in functions that insert, remove, and test
2967 watchpoints and hardware breakpoints.
2969 * Changes in the DJGPP native configuration.
2971 New command ``info dos sysinfo'' displays assorted information about
2972 the CPU, OS, memory, and DPMI server.
2974 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2975 display information about segment descriptors stored in GDT, LDT, and
2978 New commands ``info dos pde'' and ``info dos pte'' display entries
2979 from Page Directory and Page Tables (for now works with CWSDPMI only).
2980 New command ``info dos address-pte'' displays the Page Table entry for
2981 a given linear address.
2983 GDB can now pass command lines longer than 126 characters to the
2984 program being debugged (requires an update to the libdbg.a library
2985 which is part of the DJGPP development kit).
2987 DWARF2 debug info is now supported.
2989 It is now possible to `step' and `next' through calls to `longjmp'.
2991 * Changes in documentation.
2993 All GDB documentation was converted to GFDL, the GNU Free
2994 Documentation License.
2996 Tracepoints-related commands are now fully documented in the GDB
2999 TUI, the Text-mode User Interface, is now documented in the manual.
3001 Tracepoints-related commands are now fully documented in the GDB
3004 The "GDB Internals" manual now has an index. It also includes
3005 documentation of `ui_out' functions, GDB coding standards, x86
3006 hardware watchpoints, and memory region attributes.
3008 * GDB's version number moved to ``version.in''
3010 The Makefile variable VERSION has been replaced by the file
3011 ``version.in''. People creating GDB distributions should update the
3012 contents of this file.
3016 GUD support is now a standard part of the EMACS distribution.
3018 *** Changes in GDB 5.0:
3020 * Improved support for debugging FP programs on x86 targets
3022 Unified and much-improved support for debugging floating-point
3023 programs on all x86 targets. In particular, ``info float'' now
3024 displays the FP registers in the same format on all x86 targets, with
3025 greater level of detail.
3027 * Improvements and bugfixes in hardware-assisted watchpoints
3029 It is now possible to watch array elements, struct members, and
3030 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3031 on x86 targets no longer erroneously trigger when the address is
3034 * Improvements in the native DJGPP version of GDB
3036 The distribution now includes all the scripts and auxiliary files
3037 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3038 machines ``out of the box''.
3040 The DJGPP version can now debug programs that use signals. It is
3041 possible to catch signals that happened in the debuggee, deliver
3042 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3043 would kill the program being debugged.) Programs that hook hardware
3044 interrupts (keyboard, timer, etc.) can also be debugged.
3046 It is now possible to debug DJGPP programs that redirect their
3047 standard handles or switch them to raw (as opposed to cooked) mode, or
3048 even close them. The command ``run < foo > bar'' works as expected,
3049 and ``info terminal'' reports useful information about the debuggee's
3050 terminal, including raw/cooked mode, redirection, etc.
3052 The DJGPP version now uses termios functions for console I/O, which
3053 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3056 DOS-style file names with drive letters are now fully supported by
3059 It is now possible to debug DJGPP programs that switch their working
3060 directory. It is also possible to rerun the debuggee any number of
3061 times without restarting GDB; thus, you can use the same setup,
3062 breakpoints, etc. for many debugging sessions.
3064 * New native configurations
3066 ARM GNU/Linux arm*-*-linux*
3067 PowerPC GNU/Linux powerpc-*-linux*
3071 Motorola MCore mcore-*-*
3072 x86 VxWorks i[3456]86-*-vxworks*
3073 PowerPC VxWorks powerpc-*-vxworks*
3074 TI TMS320C80 tic80-*-*
3076 * OBSOLETE configurations
3078 Altos 3068 m68*-altos-*
3079 Convex c1-*-*, c2-*-*
3081 ARM RISCix arm-*-* (as host)
3084 Configurations that have been declared obsolete will be commented out,
3085 but the code will be left in place. If there is no activity to revive
3086 these configurations before the next release of GDB, the sources will
3087 be permanently REMOVED.
3089 * Gould support removed
3091 Support for the Gould PowerNode and NP1 has been removed.
3093 * New features for SVR4
3095 On SVR4 native platforms (such as Solaris), if you attach to a process
3096 without first loading a symbol file, GDB will now attempt to locate and
3097 load symbols from the running process's executable file.
3099 * Many C++ enhancements
3101 C++ support has been greatly improved. Overload resolution now works properly
3102 in almost all cases. RTTI support is on the way.
3104 * Remote targets can connect to a sub-program
3106 A popen(3) style serial-device has been added. This device starts a
3107 sub-process (such as a stand-alone simulator) and then communicates
3108 with that. The sub-program to run is specified using the syntax
3109 ``|<program> <args>'' vis:
3111 (gdb) set remotedebug 1
3112 (gdb) target extended-remote |mn10300-elf-sim program-args
3114 * MIPS 64 remote protocol
3116 A long standing bug in the mips64 remote protocol where by GDB
3117 expected certain 32 bit registers (ex SR) to be transfered as 32
3118 instead of 64 bits has been fixed.
3120 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3121 added to provide backward compatibility with older versions of GDB.
3123 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3125 The command ``set remotebinarydownload'' command has been replaced by
3126 ``set remote X-packet''. Other commands in ``set remote'' family
3127 include ``set remote P-packet''.
3129 * Breakpoint commands accept ranges.
3131 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3132 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3133 ``tracepoint passcount'' also accepts a range of tracepoints.
3135 * ``apropos'' command added.
3137 The ``apropos'' command searches through command names and
3138 documentation strings, printing out matches, making it much easier to
3139 try to find a command that does what you are looking for.
3143 A new machine oriented interface (MI) has been added to GDB. This
3144 interface is designed for debug environments running GDB as a separate
3145 process. This is part of the long term libGDB project. See the
3146 "GDB/MI" chapter of the GDB manual for further information. It can be
3147 enabled by configuring with:
3149 .../configure --enable-gdbmi
3151 *** Changes in GDB-4.18:
3153 * New native configurations
3155 HP-UX 10.20 hppa*-*-hpux10.20
3156 HP-UX 11.x hppa*-*-hpux11.0*
3157 M68K GNU/Linux m68*-*-linux*
3161 Fujitsu FR30 fr30-*-elf*
3162 Intel StrongARM strongarm-*-*
3163 Mitsubishi D30V d30v-*-*
3165 * OBSOLETE configurations
3167 Gould PowerNode, NP1 np1-*-*, pn-*-*
3169 Configurations that have been declared obsolete will be commented out,
3170 but the code will be left in place. If there is no activity to revive
3171 these configurations before the next release of GDB, the sources will
3172 be permanently REMOVED.
3176 As a compatibility experiment, GDB's source files buildsym.h and
3177 buildsym.c have been converted to pure standard C, no longer
3178 containing any K&R compatibility code. We believe that all systems in
3179 use today either come with a standard C compiler, or have a GCC port
3180 available. If this is not true, please report the affected
3181 configuration to bug-gdb@gnu.org immediately. See the README file for
3182 information about getting a standard C compiler if you don't have one
3187 GDB now uses readline 2.2.
3189 * set extension-language
3191 You can now control the mapping between filename extensions and source
3192 languages by using the `set extension-language' command. For instance,
3193 you can ask GDB to treat .c files as C++ by saying
3194 set extension-language .c c++
3195 The command `info extensions' lists all of the recognized extensions
3196 and their associated languages.
3198 * Setting processor type for PowerPC and RS/6000
3200 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3201 you can use the `set processor' command to specify what variant of the
3202 PowerPC family you are debugging. The command
3206 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3207 following PowerPC and RS6000 variants:
3209 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3210 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3212 403GC IBM PowerPC 403GC
3213 505 Motorola PowerPC 505
3214 860 Motorola PowerPC 860 or 850
3215 601 Motorola PowerPC 601
3216 602 Motorola PowerPC 602
3217 603 Motorola/IBM PowerPC 603 or 603e
3218 604 Motorola PowerPC 604 or 604e
3219 750 Motorola/IBM PowerPC 750 or 750
3221 At the moment, this command just tells GDB what to name the
3222 special-purpose processor registers. Since almost all the affected
3223 registers are inaccessible to user-level programs, this command is
3224 only useful for remote debugging in its present form.
3228 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3229 more extensive support for HP-UX. Added features include shared
3230 library support, kernel threads and hardware watchpoints for 11.00,
3231 support for HP's ANSI C and C++ compilers, and a compatibility mode
3232 for xdb and dbx commands.
3236 HP's donation includes the new concept of catchpoints, which is a
3237 generalization of the old catch command. On HP-UX, it is now possible
3238 to catch exec, fork, and vfork, as well as library loading.
3240 This means that the existing catch command has changed; its first
3241 argument now specifies the type of catch to be set up. See the
3242 output of "help catch" for a list of catchpoint types.
3244 * Debugging across forks
3246 On HP-UX, you can choose which process to debug when a fork() happens
3251 HP has donated a curses-based terminal user interface (TUI). To get
3252 it, build with --enable-tui. Although this can be enabled for any
3253 configuration, at present it only works for native HP debugging.
3255 * GDB remote protocol additions
3257 A new protocol packet 'X' that writes binary data is now available.
3258 Default behavior is to try 'X', then drop back to 'M' if the stub
3259 fails to respond. The settable variable `remotebinarydownload'
3260 allows explicit control over the use of 'X'.
3262 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3263 full 64-bit address. The command
3265 set remoteaddresssize 32
3267 can be used to revert to the old behaviour. For existing remote stubs
3268 the change should not be noticed, as the additional address information
3271 In order to assist in debugging stubs, you may use the maintenance
3272 command `packet' to send any text string to the stub. For instance,
3274 maint packet heythere
3276 sends the packet "$heythere#<checksum>". Note that it is very easy to
3277 disrupt a debugging session by sending the wrong packet at the wrong
3280 The compare-sections command allows you to compare section data on the
3281 target to what is in the executable file without uploading or
3282 downloading, by comparing CRC checksums.
3284 * Tracing can collect general expressions
3286 You may now collect general expressions at tracepoints. This requires
3287 further additions to the target-side stub; see tracepoint.c and
3288 doc/agentexpr.texi for further details.
3290 * mask-address variable for Mips
3292 For Mips targets, you may control the zeroing of the upper 32 bits of
3293 a 64-bit address by entering `set mask-address on'. This is mainly
3294 of interest to users of embedded R4xxx and R5xxx processors.
3296 * Higher serial baud rates
3298 GDB's serial code now allows you to specify baud rates 57600, 115200,
3299 230400, and 460800 baud. (Note that your host system may not be able
3300 to achieve all of these rates.)
3304 The i960 configuration now includes an initial implementation of a
3305 builtin simulator, contributed by Jim Wilson.
3308 *** Changes in GDB-4.17:
3310 * New native configurations
3312 Alpha GNU/Linux alpha*-*-linux*
3313 Unixware 2.x i[3456]86-unixware2*
3314 Irix 6.x mips*-sgi-irix6*
3315 PowerPC GNU/Linux powerpc-*-linux*
3316 PowerPC Solaris powerpcle-*-solaris*
3317 Sparc GNU/Linux sparc-*-linux*
3318 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3322 Argonaut Risc Chip (ARC) arc-*-*
3323 Hitachi H8/300S h8300*-*-*
3324 Matsushita MN10200 w/simulator mn10200-*-*
3325 Matsushita MN10300 w/simulator mn10300-*-*
3326 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3327 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3328 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3329 Mitsubishi D10V w/simulator d10v-*-*
3330 Mitsubishi M32R/D w/simulator m32r-*-elf*
3331 Tsqware Sparclet sparclet-*-*
3332 NEC V850 w/simulator v850-*-*
3334 * New debugging protocols
3336 ARM with RDI protocol arm*-*-*
3337 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3338 DDB and LSI variants of PMON protocol mips*-*-*
3339 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3340 PowerPC with SDS protocol powerpc{,le}-*-eabi
3341 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3345 All configurations can now understand and use the DWARF 2 debugging
3346 format. The choice is automatic, if the symbol file contains DWARF 2
3351 GDB now includes basic Java language support. This support is
3352 only useful with Java compilers that produce native machine code.
3354 * solib-absolute-prefix and solib-search-path
3356 For SunOS and SVR4 shared libraries, you may now set the prefix for
3357 loading absolute shared library symbol files, and the search path for
3358 locating non-absolute shared library symbol files.
3360 * Live range splitting
3362 GDB can now effectively debug code for which GCC has performed live
3363 range splitting as part of its optimization. See gdb/doc/LRS for
3364 more details on the expected format of the stabs information.
3368 GDB's support for the GNU Hurd, including thread debugging, has been
3369 updated to work with current versions of the Hurd.
3373 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3374 instruction set. ARM GDB automatically detects when Thumb
3375 instructions are in use, and adjusts disassembly and backtracing
3380 GDB's MIPS target configurations now handle the MIP16 16-bit
3385 GDB now includes support for overlays; if an executable has been
3386 linked such that multiple sections are based at the same address, GDB
3387 will decide which section to use for symbolic info. You can choose to
3388 control the decision manually, using overlay commands, or implement
3389 additional target-side support and use "overlay load-target" to bring
3390 in the overlay mapping. Do "help overlay" for more detail.
3394 The command "info symbol <address>" displays information about
3395 the symbol at the specified address.
3399 The standard remote protocol now includes an extension that allows
3400 asynchronous collection and display of trace data. This requires
3401 extensive support in the target-side debugging stub. Tracing mode
3402 includes a new interaction mode in GDB and new commands: see the
3403 file tracepoint.c for more details.
3407 Configurations for embedded MIPS now include a simulator contributed
3408 by Cygnus Solutions. The simulator supports the instruction sets
3409 of most MIPS variants.
3413 Sparc configurations may now include the ERC32 simulator contributed
3414 by the European Space Agency. The simulator is not built into
3415 Sparc targets by default; configure with --enable-sim to include it.
3419 For target configurations that may include multiple variants of a
3420 basic architecture (such as MIPS and SH), you may now set the
3421 architecture explicitly. "set arch" sets, "info arch" lists
3422 the possible architectures.
3424 *** Changes in GDB-4.16:
3426 * New native configurations
3428 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3429 M68K NetBSD m68k-*-netbsd*
3430 PowerPC AIX 4.x powerpc-*-aix*
3431 PowerPC MacOS powerpc-*-macos*
3432 PowerPC Windows NT powerpcle-*-cygwin32
3433 RS/6000 AIX 4.x rs6000-*-aix4*
3437 ARM with RDP protocol arm-*-*
3438 I960 with MON960 i960-*-coff
3439 MIPS VxWorks mips*-*-vxworks*
3440 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3441 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3443 Matra Sparclet sparclet-*-*
3447 The powerpc-eabi configuration now includes the PSIM simulator,
3448 contributed by Andrew Cagney, with assistance from Mike Meissner.
3449 PSIM is a very elaborate model of the PowerPC, including not only
3450 basic instruction set execution, but also details of execution unit
3451 performance and I/O hardware. See sim/ppc/README for more details.
3455 GDB now works with Solaris 2.5.
3457 * Windows 95/NT native
3459 GDB will now work as a native debugger on Windows 95 and Windows NT.
3460 To build it from source, you must use the "gnu-win32" environment,
3461 which uses a DLL to emulate enough of Unix to run the GNU tools.
3462 Further information, binaries, and sources are available at
3463 ftp.cygnus.com, under pub/gnu-win32.
3465 * dont-repeat command
3467 If a user-defined command includes the command `dont-repeat', then the
3468 command will not be repeated if the user just types return. This is
3469 useful if the command is time-consuming to run, so that accidental
3470 extra keystrokes don't run the same command many times.
3472 * Send break instead of ^C
3474 The standard remote protocol now includes an option to send a break
3475 rather than a ^C to the target in order to interrupt it. By default,
3476 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3478 * Remote protocol timeout
3480 The standard remote protocol includes a new variable `remotetimeout'
3481 that allows you to set the number of seconds before GDB gives up trying
3482 to read from the target. The default value is 2.
3484 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3486 By default GDB will automatically keep track of objects as they are
3487 loaded and unloaded by the dynamic linker. By using the command `set
3488 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3489 when shared library events occur, thus allowing you to set breakpoints
3490 in shared libraries which are explicitly loaded by the inferior.
3492 Note this feature does not work on hpux8. On hpux9 you must link
3493 /usr/lib/end.o into your program. This feature should work
3494 automatically on hpux10.
3496 * Irix 5.x hardware watchpoint support
3498 Irix 5 configurations now support the use of hardware watchpoints.
3500 * Mips protocol "SYN garbage limit"
3502 When debugging a Mips target using the `target mips' protocol, you
3503 may set the number of characters that GDB will ignore by setting
3504 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3505 every character. The default value is 1050.
3507 * Recording and replaying remote debug sessions
3509 If you set `remotelogfile' to the name of a file, gdb will write to it
3510 a recording of a remote debug session. This recording may then be
3511 replayed back to gdb using "gdbreplay". See gdbserver/README for
3512 details. This is useful when you have a problem with GDB while doing
3513 remote debugging; you can make a recording of the session and send it
3514 to someone else, who can then recreate the problem.
3516 * Speedups for remote debugging
3518 GDB includes speedups for downloading and stepping MIPS systems using
3519 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3520 and more efficient S-record downloading.
3522 * Memory use reductions and statistics collection
3524 GDB now uses less memory and reports statistics about memory usage.
3525 Try the `maint print statistics' command, for example.
3527 *** Changes in GDB-4.15:
3529 * Psymtabs for XCOFF
3531 The symbol reader for AIX GDB now uses partial symbol tables. This
3532 can greatly improve startup time, especially for large executables.
3534 * Remote targets use caching
3536 Remote targets now use a data cache to speed up communication with the
3537 remote side. The data cache could lead to incorrect results because
3538 it doesn't know about volatile variables, thus making it impossible to
3539 debug targets which use memory mapped I/O devices. `set remotecache
3540 off' turns the the data cache off.
3542 * Remote targets may have threads
3544 The standard remote protocol now includes support for multiple threads
3545 in the target system, using new protocol commands 'H' and 'T'. See
3546 gdb/remote.c for details.
3550 If GDB is configured with `--enable-netrom', then it will include
3551 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3552 acts as though it is a bank of ROM on the target board, but you can
3553 write into it over the network. GDB's support consists only of
3554 support for fast loading into the emulated ROM; to debug, you must use
3555 another protocol, such as standard remote protocol. The usual
3556 sequence is something like
3558 target nrom <netrom-hostname>
3560 target remote <netrom-hostname>:1235
3564 GDB now includes support for the Apple Macintosh, as a host only. It
3565 may be run as either an MPW tool or as a standalone application, and
3566 it can debug through the serial port. All the usual GDB commands are
3567 available, but to the target command, you must supply "serial" as the
3568 device type instead of "/dev/ttyXX". See mpw-README in the main
3569 directory for more information on how to build. The MPW configuration
3570 scripts */mpw-config.in support only a few targets, and only the
3571 mips-idt-ecoff target has been tested.
3575 GDB configuration now uses autoconf. This is not user-visible,
3576 but does simplify configuration and building.
3580 GDB now supports hpux10.
3582 *** Changes in GDB-4.14:
3584 * New native configurations
3586 x86 FreeBSD i[345]86-*-freebsd
3587 x86 NetBSD i[345]86-*-netbsd
3588 NS32k NetBSD ns32k-*-netbsd
3589 Sparc NetBSD sparc-*-netbsd
3593 A29K VxWorks a29k-*-vxworks
3594 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3595 CPU32 EST-300 emulator m68*-*-est*
3596 PowerPC ELF powerpc-*-elf
3599 * Alpha OSF/1 support for procfs
3601 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3602 possible to attach to running processes. As the mounting of the /proc
3603 filesystem is optional on the Alpha, GDB automatically determines
3604 the availability of /proc during startup. This can lead to problems
3605 if /proc is unmounted after GDB has been started.
3607 * Arguments to user-defined commands
3609 User commands may accept up to 10 arguments separated by whitespace.
3610 Arguments are accessed within the user command via $arg0..$arg9. A
3613 print $arg0 + $arg1 + $arg2
3615 To execute the command use:
3618 Defines the command "adder" which prints the sum of its three arguments.
3619 Note the arguments are text substitutions, so they may reference variables,
3620 use complex expressions, or even perform inferior function calls.
3622 * New `if' and `while' commands
3624 This makes it possible to write more sophisticated user-defined
3625 commands. Both commands take a single argument, which is the
3626 expression to evaluate, and must be followed by the commands to
3627 execute, one per line, if the expression is nonzero, the list being
3628 terminated by the word `end'. The `if' command list may include an
3629 `else' word, which causes the following commands to be executed only
3630 if the expression is zero.
3632 * Fortran source language mode
3634 GDB now includes partial support for Fortran 77. It will recognize
3635 Fortran programs and can evaluate a subset of Fortran expressions, but
3636 variables and functions may not be handled correctly. GDB will work
3637 with G77, but does not yet know much about symbols emitted by other
3640 * Better HPUX support
3642 Most debugging facilities now work on dynamic executables for HPPAs
3643 running hpux9 or later. You can attach to running dynamically linked
3644 processes, but by default the dynamic libraries will be read-only, so
3645 for instance you won't be able to put breakpoints in them. To change
3646 that behavior do the following before running the program:
3652 This will cause the libraries to be mapped private and read-write.
3653 To revert to the normal behavior, do this:
3659 You cannot set breakpoints or examine data in the library until after
3660 the library is loaded if the function/data symbols do not have
3663 GDB can now also read debug symbols produced by the HP C compiler on
3664 HPPAs (sorry, no C++, Fortran or 68k support).
3666 * Target byte order now dynamically selectable
3668 You can choose which byte order to use with a target system, via the
3669 commands "set endian big" and "set endian little", and you can see the
3670 current setting by using "show endian". You can also give the command
3671 "set endian auto", in which case GDB will use the byte order
3672 associated with the executable. Currently, only embedded MIPS
3673 configurations support dynamic selection of target byte order.
3675 * New DOS host serial code
3677 This version uses DPMI interrupts to handle buffered I/O, so you
3678 no longer need to run asynctsr when debugging boards connected to
3681 *** Changes in GDB-4.13:
3683 * New "complete" command
3685 This lists all the possible completions for the rest of the line, if it
3686 were to be given as a command itself. This is intended for use by emacs.
3688 * Trailing space optional in prompt
3690 "set prompt" no longer adds a space for you after the prompt you set. This
3691 allows you to set a prompt which ends in a space or one that does not.
3693 * Breakpoint hit counts
3695 "info break" now displays a count of the number of times the breakpoint
3696 has been hit. This is especially useful in conjunction with "ignore"; you
3697 can ignore a large number of breakpoint hits, look at the breakpoint info
3698 to see how many times the breakpoint was hit, then run again, ignoring one
3699 less than that number, and this will get you quickly to the last hit of
3702 * Ability to stop printing at NULL character
3704 "set print null-stop" will cause GDB to stop printing the characters of
3705 an array when the first NULL is encountered. This is useful when large
3706 arrays actually contain only short strings.
3708 * Shared library breakpoints
3710 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3711 breakpoints in shared libraries before the executable is run.
3713 * Hardware watchpoints
3715 There is a new hardware breakpoint for the watch command for sparclite
3716 targets. See gdb/sparclite/hw_breakpoint.note.
3718 Hardware watchpoints are also now supported under GNU/Linux.
3722 Annotations have been added. These are for use with graphical interfaces,
3723 and are still experimental. Currently only gdba.el uses these.
3725 * Improved Irix 5 support
3727 GDB now works properly with Irix 5.2.
3729 * Improved HPPA support
3731 GDB now works properly with the latest GCC and GAS.
3733 * New native configurations
3735 Sequent PTX4 i[34]86-sequent-ptx4
3736 HPPA running OSF/1 hppa*-*-osf*
3737 Atari TT running SVR4 m68*-*-sysv4*
3738 RS/6000 LynxOS rs6000-*-lynxos*
3742 OS/9000 i[34]86-*-os9k
3743 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3746 * Hitachi SH7000 and E7000-PC ICE support
3748 There is now support for communicating with the Hitachi E7000-PC ICE.
3749 This is available automatically when GDB is configured for the SH.
3753 As usual, a variety of small fixes and improvements, both generic
3754 and configuration-specific. See the ChangeLog for more detail.
3756 *** Changes in GDB-4.12:
3758 * Irix 5 is now supported
3762 GDB-4.12 on the HPPA has a number of changes which make it unable
3763 to debug the output from the currently released versions of GCC and
3764 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3765 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3766 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3769 *** Changes in GDB-4.11:
3771 * User visible changes:
3775 The "set remotedebug" option is now consistent between the mips remote
3776 target, remote targets using the gdb-specific protocol, UDI (AMD's
3777 debug protocol for the 29k) and the 88k bug monitor. It is now an
3778 integer specifying a debug level (normally 0 or 1, but 2 means more
3779 debugging info for the mips target).
3781 * DEC Alpha native support
3783 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3784 debug info, but GDB works fairly well with the DEC compiler and should
3785 work with a future GCC release. See the README file for a few
3786 Alpha-specific notes.
3788 * Preliminary thread implementation
3790 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3792 * LynxOS native and target support for 386
3794 This release has been hosted on LynxOS 2.2, and also can be configured
3795 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3798 * Improvements in C++ mangling/demangling.
3800 This release has much better g++ debugging, specifically in name
3801 mangling/demangling, virtual function calls, print virtual table,
3802 call methods, ...etc.
3804 *** Changes in GDB-4.10:
3806 * User visible changes:
3808 Remote debugging using the GDB-specific (`target remote') protocol now
3809 supports the `load' command. This is only useful if you have some
3810 other way of getting the stub to the target system, and you can put it
3811 somewhere in memory where it won't get clobbered by the download.
3813 Filename completion now works.
3815 When run under emacs mode, the "info line" command now causes the
3816 arrow to point to the line specified. Also, "info line" prints
3817 addresses in symbolic form (as well as hex).
3819 All vxworks based targets now support a user settable option, called
3820 vxworks-timeout. This option represents the number of seconds gdb
3821 should wait for responses to rpc's. You might want to use this if
3822 your vxworks target is, perhaps, a slow software simulator or happens
3823 to be on the far side of a thin network line.
3827 This release contains support for using a DEC alpha as a GDB host for
3828 cross debugging. Native alpha debugging is not supported yet.
3831 *** Changes in GDB-4.9:
3835 This is the first GDB release which is accompanied by a matching testsuite.
3836 The testsuite requires installation of dejagnu, which should be available
3837 via ftp from most sites that carry GNU software.
3841 'Cfront' style demangling has had its name changed to 'ARM' style, to
3842 emphasize that it was written from the specifications in the C++ Annotated
3843 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3844 disclaimers, it still generated too much confusion with users attempting to
3845 use gdb with AT&T cfront.
3849 GDB now uses a standard remote interface to a simulator library.
3850 So far, the library contains simulators for the Zilog Z8001/2, the
3851 Hitachi H8/300, H8/500 and Super-H.
3853 * New targets supported
3855 H8/300 simulator h8300-hitachi-hms or h8300hms
3856 H8/500 simulator h8500-hitachi-hms or h8500hms
3857 SH simulator sh-hitachi-hms or sh
3858 Z8000 simulator z8k-zilog-none or z8ksim
3859 IDT MIPS board over serial line mips-idt-ecoff
3861 Cross-debugging to GO32 targets is supported. It requires a custom
3862 version of the i386-stub.c module which is integrated with the
3863 GO32 memory extender.
3865 * New remote protocols
3867 MIPS remote debugging protocol.
3869 * New source languages supported
3871 This version includes preliminary support for Chill, a Pascal like language
3872 used by telecommunications companies. Chill support is also being integrated
3873 into the GNU compiler, but we don't know when it will be publically available.
3876 *** Changes in GDB-4.8:
3878 * HP Precision Architecture supported
3880 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3881 version of this support was available as a set of patches from the
3882 University of Utah. GDB does not support debugging of programs
3883 compiled with the HP compiler, because HP will not document their file
3884 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3885 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3887 Many problems in the preliminary version have been fixed.
3889 * Faster and better demangling
3891 We have improved template demangling and fixed numerous bugs in the GNU style
3892 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3893 character types (wchar_t) are now supported. Demangling of each symbol is now
3894 only done once, and is cached when the symbol table for a file is read in.
3895 This results in a small increase in memory usage for C programs, a moderate
3896 increase in memory usage for C++ programs, and a fantastic speedup in
3899 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3900 from the specifications in the Annotated Reference Manual, which AT&T's
3901 compiler does not actually implement.
3903 * G++ multiple inheritance compiler problem
3905 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3906 inheritance lattices was reworked to properly discover ambiguities. We
3907 recently found an example which causes this new algorithm to fail in a
3908 very subtle way, producing bad debug information for those classes.
3909 The file 'gcc.patch' (in this directory) can be applied to gcc to
3910 circumvent the problem. A future GCC release will contain a complete
3913 The previous G++ debug info problem (mentioned below for the gdb-4.7
3914 release) is fixed in gcc version 2.3.2.
3916 * Improved configure script
3918 The `configure' script will now attempt to guess your system type if
3919 you don't supply a host system type. The old scheme of supplying a
3920 host system triplet is preferable over using this. All the magic is
3921 done in the new `config.guess' script. Examine it for details.
3923 We have also brought our configure script much more in line with the FSF's
3924 version. It now supports the --with-xxx options. In particular,
3925 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3926 The resulting GDB will not be able to read arbitrary object file formats --
3927 only the format ``expected'' to be used on the configured target system.
3928 We hope to make this the default in a future release.
3930 * Documentation improvements
3932 There's new internal documentation on how to modify GDB, and how to
3933 produce clean changes to the code. We implore people to read it
3934 before submitting changes.
3936 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3937 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3938 `info' files are also provided. To build `info' files from scratch,
3939 you will need the latest `makeinfo' release, which will be available in
3940 a future texinfo-X.Y release.
3942 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3943 We're not sure exactly which versions have this problem, but it has
3944 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3945 or better. If that isn't possible, there is a patch in
3946 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3947 around this problem.
3951 GDB now supports array constants that can be used in expressions typed in by
3952 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3953 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3956 The new directory `gdb/sparclite' contains a program that demonstrates
3957 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3959 * New native hosts supported
3961 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3962 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3964 * New targets supported
3966 AMD 29k family via UDI a29k-amd-udi or udi29k
3968 * New file formats supported
3970 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3971 HPUX core files, and SCO 3.2v2 core files.
3975 Attaching to processes now works again; thanks for the many bug reports.
3977 We have also stomped on a bunch of core dumps caused by
3978 printf_filtered("%s") problems.
3980 We eliminated a copyright problem on the rpc and ptrace header files
3981 for VxWorks, which was discovered at the last minute during the 4.7
3982 release. You should now be able to build a VxWorks GDB.
3984 You can now interrupt gdb while an attached process is running. This
3985 will cause the attached process to stop, and give control back to GDB.
3987 We fixed problems caused by using too many file descriptors
3988 for reading symbols from object files and libraries. This was
3989 especially a problem for programs that used many (~100) shared
3992 The `step' command now only enters a subroutine if there is line number
3993 information for the subroutine. Otherwise it acts like the `next'
3994 command. Previously, `step' would enter subroutines if there was
3995 any debugging information about the routine. This avoids problems
3996 when using `cc -g1' on MIPS machines.
3998 * Internal improvements
4000 GDB's internal interfaces have been improved to make it easier to support
4001 debugging of multiple languages in the future.
4003 GDB now uses a common structure for symbol information internally.
4004 Minimal symbols (derived from linkage symbols in object files), partial
4005 symbols (from a quick scan of debug information), and full symbols
4006 contain a common subset of information, making it easier to write
4007 shared code that handles any of them.
4009 * New command line options
4011 We now accept --silent as an alias for --quiet.
4015 The memory-mapped-malloc library is now licensed under the GNU Library
4016 General Public License.
4018 *** Changes in GDB-4.7:
4020 * Host/native/target split
4022 GDB has had some major internal surgery to untangle the support for
4023 hosts and remote targets. Now, when you configure GDB for a remote
4024 target, it will no longer load in all of the support for debugging
4025 local programs on the host. When fully completed and tested, this will
4026 ensure that arbitrary host/target combinations are possible.
4028 The primary conceptual shift is to separate the non-portable code in
4029 GDB into three categories. Host specific code is required any time GDB
4030 is compiled on that host, regardless of the target. Target specific
4031 code relates to the peculiarities of the target, but can be compiled on
4032 any host. Native specific code is everything else: it can only be
4033 built when the host and target are the same system. Child process
4034 handling and core file support are two common `native' examples.
4036 GDB's use of /proc for controlling Unix child processes is now cleaner.
4037 It has been split out into a single module under the `target_ops' vector,
4038 plus two native-dependent functions for each system that uses /proc.
4040 * New hosts supported
4042 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4043 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4044 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4046 * New targets supported
4048 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4049 68030 and CPU32 m68030-*-*, m68332-*-*
4051 * New native hosts supported
4053 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4054 (386bsd is not well tested yet)
4055 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4057 * New file formats supported
4059 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4060 supports reading of `a.out.adobe' object files, which are an a.out
4061 format extended with minimal information about multiple sections.
4065 `show copying' is the same as the old `info copying'.
4066 `show warranty' is the same as `info warrantee'.
4067 These were renamed for consistency. The old commands continue to work.
4069 `info handle' is a new alias for `info signals'.
4071 You can now define pre-command hooks, which attach arbitrary command
4072 scripts to any command. The commands in the hook will be executed
4073 prior to the user's command. You can also create a hook which will be
4074 executed whenever the program stops. See gdb.texinfo.
4078 We now deal with Cfront style name mangling, and can even extract type
4079 info from mangled symbols. GDB can automatically figure out which
4080 symbol mangling style your C++ compiler uses.
4082 Calling of methods and virtual functions has been improved as well.
4086 The crash that occured when debugging Sun Ansi-C compiled binaries is
4087 fixed. This was due to mishandling of the extra N_SO stabs output
4090 We also finally got Ultrix 4.2 running in house, and fixed core file
4091 support, with help from a dozen people on the net.
4093 John M. Farrell discovered that the reason that single-stepping was so
4094 slow on all of the Mips based platforms (primarily SGI and DEC) was
4095 that we were trying to demangle and lookup a symbol used for internal
4096 purposes on every instruction that was being stepped through. Changing
4097 the name of that symbol so that it couldn't be mistaken for a C++
4098 mangled symbol sped things up a great deal.
4100 Rich Pixley sped up symbol lookups in general by getting much smarter
4101 about when C++ symbol mangling is necessary. This should make symbol
4102 completion (TAB on the command line) much faster. It's not as fast as
4103 we'd like, but it's significantly faster than gdb-4.6.
4107 A new user controllable variable 'call_scratch_address' can
4108 specify the location of a scratch area to be used when GDB
4109 calls a function in the target. This is necessary because the
4110 usual method of putting the scratch area on the stack does not work
4111 in systems that have separate instruction and data spaces.
4113 We integrated changes to support the 29k UDI (Universal Debugger
4114 Interface), but discovered at the last minute that we didn't have all
4115 of the appropriate copyright paperwork. We are working with AMD to
4116 resolve this, and hope to have it available soon.
4120 We have sped up the remote serial line protocol, especially for targets
4121 with lots of registers. It now supports a new `expedited status' ('T')
4122 message which can be used in place of the existing 'S' status message.
4123 This allows the remote stub to send only the registers that GDB
4124 needs to make a quick decision about single-stepping or conditional
4125 breakpoints, eliminating the need to fetch the entire register set for
4126 each instruction being stepped through.
4128 The GDB remote serial protocol now implements a write-through cache for
4129 registers, only re-reading the registers if the target has run.
4131 There is also a new remote serial stub for SPARC processors. You can
4132 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4133 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4134 processor with a serial port.
4138 Configure.in files have become much easier to read and modify. A new
4139 `table driven' format makes it more obvious what configurations are
4140 supported, and what files each one uses.
4144 There is a new opcodes library which will eventually contain all of the
4145 disassembly routines and opcode tables. At present, it only contains
4146 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4147 disassembler (binutils/objdump) to share these routines.
4149 The libiberty library is now copylefted under the GNU Library General
4150 Public License. This allows more liberal use, and was done so libg++
4151 can use it. This makes no difference to GDB, since the Library License
4152 grants all the rights from the General Public License.
4156 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4157 reference to the stabs symbol info used by the debugger. It is (as far
4158 as we know) the only published document on this fascinating topic. We
4159 encourage you to read it, compare it to the stabs information on your
4160 system, and send improvements on the document in general (to
4161 bug-gdb@prep.ai.mit.edu).
4163 And, of course, many bugs have been fixed.
4166 *** Changes in GDB-4.6:
4168 * Better support for C++ function names
4170 GDB now accepts as input the "demangled form" of C++ overloaded function
4171 names and member function names, and can do command completion on such names
4172 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4173 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4174 Make use of command completion, it is your friend.
4176 GDB also now accepts a variety of C++ mangled symbol formats. They are
4177 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4178 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4179 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4180 for the list of formats.
4182 * G++ symbol mangling problem
4184 Recent versions of gcc have a bug in how they emit debugging information for
4185 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4186 directory) can be applied to gcc to fix the problem. Alternatively, if you
4187 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4188 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4189 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4192 * New 'maintenance' command
4194 All of the commands related to hacking GDB internals have been moved out of
4195 the main command set, and now live behind the 'maintenance' command. This
4196 can also be abbreviated as 'mt'. The following changes were made:
4198 dump-me -> maintenance dump-me
4199 info all-breakpoints -> maintenance info breakpoints
4200 printmsyms -> maintenance print msyms
4201 printobjfiles -> maintenance print objfiles
4202 printpsyms -> maintenance print psymbols
4203 printsyms -> maintenance print symbols
4205 The following commands are new:
4207 maintenance demangle Call internal GDB demangler routine to
4208 demangle a C++ link name and prints the result.
4209 maintenance print type Print a type chain for a given symbol
4211 * Change to .gdbinit file processing
4213 We now read the $HOME/.gdbinit file before processing the argv arguments
4214 (e.g. reading symbol files or core files). This allows global parameters to
4215 be set, which will apply during the symbol reading. The ./.gdbinit is still
4216 read after argv processing.
4218 * New hosts supported
4220 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4222 GNU/Linux support i386-unknown-linux or linux
4224 We are also including code to support the HP/PA running BSD and HPUX. This
4225 is almost guaranteed not to work, as we didn't have time to test or build it
4226 for this release. We are including it so that the more adventurous (or
4227 masochistic) of you can play with it. We also had major problems with the
4228 fact that the compiler that we got from HP doesn't support the -g option.
4231 * New targets supported
4233 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4235 * More smarts about finding #include files
4237 GDB now remembers the compilation directory for all include files, and for
4238 all files from which C is generated (like yacc and lex sources). This
4239 greatly improves GDB's ability to find yacc/lex sources, and include files,
4240 especially if you are debugging your program from a directory different from
4241 the one that contains your sources.
4243 We also fixed a bug which caused difficulty with listing and setting
4244 breakpoints in include files which contain C code. (In the past, you had to
4245 try twice in order to list an include file that you hadn't looked at before.)
4247 * Interesting infernals change
4249 GDB now deals with arbitrary numbers of sections, where the symbols for each
4250 section must be relocated relative to that section's landing place in the
4251 target's address space. This work was needed to support ELF with embedded
4252 stabs used by Solaris-2.0.
4254 * Bug fixes (of course!)
4256 There have been loads of fixes for the following things:
4257 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4258 i960, stabs, DOS(GO32), procfs, etc...
4260 See the ChangeLog for details.
4262 *** Changes in GDB-4.5:
4264 * New machines supported (host and target)
4266 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4268 SGI Irix-4.x mips-sgi-irix4 or iris4
4270 * New malloc package
4272 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4273 Mmalloc is capable of handling mutiple heaps of memory. It is also
4274 capable of saving a heap to a file, and then mapping it back in later.
4275 This can be used to greatly speedup the startup of GDB by using a
4276 pre-parsed symbol table which lives in a mmalloc managed heap. For
4277 more details, please read mmalloc/mmalloc.texi.
4281 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4282 'help info proc' for details.
4284 * MIPS ecoff symbol table format
4286 The code that reads MIPS symbol table format is now supported on all hosts.
4287 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4290 * File name changes for MS-DOS
4292 Many files in the config directories have been renamed to make it easier to
4293 support GDB on MS-DOSe systems (which have very restrictive file name
4294 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4295 environment) is close to working but has some remaining problems. Note
4296 that debugging of DOS programs is not supported, due to limitations
4297 in the ``operating system'', but it can be used to host cross-debugging.
4299 * Cross byte order fixes
4301 Many fixes have been made to support cross debugging of Sparc and MIPS
4302 targets from hosts whose byte order differs.
4304 * New -mapped and -readnow options
4306 If memory-mapped files are available on your system through the 'mmap'
4307 system call, you can use the -mapped option on the `file' or
4308 `symbol-file' commands to cause GDB to write the symbols from your
4309 program into a reusable file. If the program you are debugging is
4310 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4311 Future GDB debugging sessions will notice the presence of this file,
4312 and will quickly map in symbol information from it, rather than reading
4313 the symbol table from the executable program. Using the '-mapped'
4314 option in a GDB `file' or `symbol-file' command has the same effect as
4315 starting GDB with the '-mapped' command-line option.
4317 You can cause GDB to read the entire symbol table immediately by using
4318 the '-readnow' option with any of the commands that load symbol table
4319 information (or on the GDB command line). This makes the command
4320 slower, but makes future operations faster.
4322 The -mapped and -readnow options are typically combined in order to
4323 build a `fred.syms' file that contains complete symbol information.
4324 A simple GDB invocation to do nothing but build a `.syms' file for future
4327 gdb -batch -nx -mapped -readnow programname
4329 The `.syms' file is specific to the host machine on which GDB is run.
4330 It holds an exact image of GDB's internal symbol table. It cannot be
4331 shared across multiple host platforms.
4333 * longjmp() handling
4335 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4336 siglongjmp() without losing control. This feature has not yet been ported to
4337 all systems. It currently works on many 386 platforms, all MIPS-based
4338 platforms (SGI, DECstation, etc), and Sun3/4.
4342 Preliminary work has been put in to support the new Solaris OS from Sun. At
4343 this time, it can control and debug processes, but it is not capable of
4348 As always, many many bug fixes. The major areas were with g++, and mipsread.
4349 People using the MIPS-based platforms should experience fewer mysterious
4350 crashes and trashed symbol tables.
4352 *** Changes in GDB-4.4:
4354 * New machines supported (host and target)
4356 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4358 BSD Reno on Vax vax-dec-bsd
4359 Ultrix on Vax vax-dec-ultrix
4361 * New machines supported (target)
4363 AMD 29000 embedded, using EBMON a29k-none-none
4367 GDB continues to improve its handling of C++. `References' work better.
4368 The demangler has also been improved, and now deals with symbols mangled as
4369 per the Annotated C++ Reference Guide.
4371 GDB also now handles `stabs' symbol information embedded in MIPS
4372 `ecoff' symbol tables. Since the ecoff format was not easily
4373 extensible to handle new languages such as C++, this appeared to be a
4374 good way to put C++ debugging info into MIPS binaries. This option
4375 will be supported in the GNU C compiler, version 2, when it is
4378 * New features for SVR4
4380 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4381 shared libraries. Debugging dynamically linked programs should present
4382 only minor differences from debugging statically linked programs.
4384 The `info proc' command will print out information about any process
4385 on an SVR4 system (including the one you are debugging). At the moment,
4386 it prints the address mappings of the process.
4388 If you bring up GDB on another SVR4 system, please send mail to
4389 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4391 * Better dynamic linking support in SunOS
4393 Reading symbols from shared libraries which contain debugging symbols
4394 now works properly. However, there remain issues such as automatic
4395 skipping of `transfer vector' code during function calls, which
4396 make it harder to debug code in a shared library, than to debug the
4397 same code linked statically.
4401 GDB is now using the latest `getopt' routines from the FSF. This
4402 version accepts the -- prefix for options with long names. GDB will
4403 continue to accept the old forms (-option and +option) as well.
4404 Various single letter abbreviations for options have been explicity
4405 added to the option table so that they won't get overshadowed in the
4406 future by other options that begin with the same letter.
4410 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4411 Many assorted bugs have been handled. Many more remain to be handled.
4412 See the various ChangeLog files (primarily in gdb and bfd) for details.
4415 *** Changes in GDB-4.3:
4417 * New machines supported (host and target)
4419 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4420 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4421 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4423 * Almost SCO Unix support
4425 We had hoped to support:
4426 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4427 (except for core file support), but we discovered very late in the release
4428 that it has problems with process groups that render gdb unusable. Sorry
4429 about that. I encourage people to fix it and post the fixes.
4431 * Preliminary ELF and DWARF support
4433 GDB can read ELF object files on System V Release 4, and can handle
4434 debugging records for C, in DWARF format, in ELF files. This support
4435 is preliminary. If you bring up GDB on another SVR4 system, please
4436 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4441 GDB now uses the latest `readline' library. One user-visible change
4442 is that two tabs will list possible command completions, which previously
4443 required typing M-? (meta-question mark, or ESC ?).
4447 The `stepi' bug that many of you noticed has been squashed.
4448 Many bugs in C++ have been handled. Many more remain to be handled.
4449 See the various ChangeLog files (primarily in gdb and bfd) for details.
4451 * State of the MIPS world (in case you wondered):
4453 GDB can understand the symbol tables emitted by the compilers
4454 supplied by most vendors of MIPS-based machines, including DEC. These
4455 symbol tables are in a format that essentially nobody else uses.
4457 Some versions of gcc come with an assembler post-processor called
4458 mips-tfile. This program is required if you want to do source-level
4459 debugging of gcc-compiled programs. I believe FSF does not ship
4460 mips-tfile with gcc version 1, but it will eventually come with gcc
4463 Debugging of g++ output remains a problem. g++ version 1.xx does not
4464 really support it at all. (If you're lucky, you should be able to get
4465 line numbers and stack traces to work, but no parameters or local
4466 variables.) With some work it should be possible to improve the
4469 When gcc version 2 is released, you will have somewhat better luck.
4470 However, even then you will get confusing results for inheritance and
4473 We will eventually provide full debugging of g++ output on
4474 DECstations. This will probably involve some kind of stabs-in-ecoff
4475 encapulation, but the details have not been worked out yet.
4478 *** Changes in GDB-4.2:
4480 * Improved configuration
4482 Only one copy of `configure' exists now, and it is not self-modifying.
4483 Porting BFD is simpler.
4487 The `step' and `next' commands now only stop at the first instruction
4488 of a source line. This prevents the multiple stops that used to occur
4489 in switch statements, for-loops, etc. `Step' continues to stop if a
4490 function that has debugging information is called within the line.
4494 Lots of small bugs fixed. More remain.
4496 * New host supported (not target)
4498 Intel 386 PC clone running Mach i386-none-mach
4501 *** Changes in GDB-4.1:
4503 * Multiple source language support
4505 GDB now has internal scaffolding to handle several source languages.
4506 It determines the type of each source file from its filename extension,
4507 and will switch expression parsing and number formatting to match the
4508 language of the function in the currently selected stack frame.
4509 You can also specifically set the language to be used, with
4510 `set language c' or `set language modula-2'.
4514 GDB now has preliminary support for the GNU Modula-2 compiler,
4515 currently under development at the State University of New York at
4516 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4517 continue through the fall of 1991 and into 1992.
4519 Other Modula-2 compilers are currently not supported, and attempting to
4520 debug programs compiled with them will likely result in an error as the
4521 symbol table is read. Feel free to work on it, though!
4523 There are hooks in GDB for strict type checking and range checking,
4524 in the `Modula-2 philosophy', but they do not currently work.
4528 GDB can now write to executable and core files (e.g. patch
4529 a variable's value). You must turn this switch on, specify
4530 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4531 by assigning a new value to a variable. Modifications take
4534 * Automatic SunOS shared library reading
4536 When you run your program, GDB automatically determines where its
4537 shared libraries (if any) have been loaded, and reads their symbols.
4538 The `share' command is no longer needed. This also works when
4539 examining core files.
4543 You can specify the number of lines that the `list' command shows.
4546 * New machines supported (host and target)
4548 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4549 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4550 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4552 * New hosts supported (not targets)
4554 IBM RT/PC: romp-ibm-aix or rtpc
4556 * New targets supported (not hosts)
4558 AMD 29000 embedded with COFF a29k-none-coff
4559 AMD 29000 embedded with a.out a29k-none-aout
4560 Ultracomputer remote kernel debug a29k-nyu-kern
4562 * New remote interfaces
4568 *** Changes in GDB-4.0:
4572 Wide output is wrapped at good places to make the output more readable.
4574 Gdb now supports cross-debugging from a host machine of one type to a
4575 target machine of another type. Communication with the target system
4576 is over serial lines. The ``target'' command handles connecting to the
4577 remote system; the ``load'' command will download a program into the
4578 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4579 also supports debugging of realtime processes running under VxWorks,
4580 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4581 stub on the target system.
4583 New CPUs supported include the AMD 29000 and Intel 960.
4585 GDB now reads object files and symbol tables via a ``binary file''
4586 library, which allows a single copy of GDB to debug programs of multiple
4587 object file types such as a.out and coff.
4589 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4590 refcard.dvi and refcard.ps are available to format it).
4593 * Control-Variable user interface simplified
4595 All variables that control the operation of the debugger can be set
4596 by the ``set'' command, and displayed by the ``show'' command.
4598 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4599 ``Show prompt'' produces the response:
4600 Gdb's prompt is new-gdb=>.
4602 What follows are the NEW set commands. The command ``help set'' will
4603 print a complete list of old and new set commands. ``help set FOO''
4604 will give a longer description of the variable FOO. ``show'' will show
4605 all of the variable descriptions and their current settings.
4607 confirm on/off: Enables warning questions for operations that are
4608 hard to recover from, e.g. rerunning the program while
4609 it is already running. Default is ON.
4611 editing on/off: Enables EMACS style command line editing
4612 of input. Previous lines can be recalled with
4613 control-P, the current line can be edited with control-B,
4614 you can search for commands with control-R, etc.
4617 history filename NAME: NAME is where the gdb command history
4618 will be stored. The default is .gdb_history,
4619 or the value of the environment variable
4622 history size N: The size, in commands, of the command history. The
4623 default is 256, or the value of the environment variable
4626 history save on/off: If this value is set to ON, the history file will
4627 be saved after exiting gdb. If set to OFF, the
4628 file will not be saved. The default is OFF.
4630 history expansion on/off: If this value is set to ON, then csh-like
4631 history expansion will be performed on
4632 command line input. The default is OFF.
4634 radix N: Sets the default radix for input and output. It can be set
4635 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4636 in the current radix, so "set radix 10" is always a no-op.
4638 height N: This integer value is the number of lines on a page. Default
4639 is 24, the current `stty rows'' setting, or the ``li#''
4640 setting from the termcap entry matching the environment
4643 width N: This integer value is the number of characters on a line.
4644 Default is 80, the current `stty cols'' setting, or the ``co#''
4645 setting from the termcap entry matching the environment
4648 Note: ``set screensize'' is obsolete. Use ``set height'' and
4649 ``set width'' instead.
4651 print address on/off: Print memory addresses in various command displays,
4652 such as stack traces and structure values. Gdb looks
4653 more ``symbolic'' if you turn this off; it looks more
4654 ``machine level'' with it on. Default is ON.
4656 print array on/off: Prettyprint arrays. New convenient format! Default
4659 print demangle on/off: Print C++ symbols in "source" form if on,
4662 print asm-demangle on/off: Same, for assembler level printouts
4665 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4668 * Support for Epoch Environment.
4670 The epoch environment is a version of Emacs v18 with windowing. One
4671 new command, ``inspect'', is identical to ``print'', except that if you
4672 are running in the epoch environment, the value is printed in its own
4676 * Support for Shared Libraries
4678 GDB can now debug programs and core files that use SunOS shared libraries.
4679 Symbols from a shared library cannot be referenced
4680 before the shared library has been linked with the program (this
4681 happens after you type ``run'' and before the function main() is entered).
4682 At any time after this linking (including when examining core files
4683 from dynamically linked programs), gdb reads the symbols from each
4684 shared library when you type the ``sharedlibrary'' command.
4685 It can be abbreviated ``share''.
4687 sharedlibrary REGEXP: Load shared object library symbols for files
4688 matching a unix regular expression. No argument
4689 indicates to load symbols for all shared libraries.
4691 info sharedlibrary: Status of loaded shared libraries.
4696 A watchpoint stops execution of a program whenever the value of an
4697 expression changes. Checking for this slows down execution
4698 tremendously whenever you are in the scope of the expression, but is
4699 quite useful for catching tough ``bit-spreader'' or pointer misuse
4700 problems. Some machines such as the 386 have hardware for doing this
4701 more quickly, and future versions of gdb will use this hardware.
4703 watch EXP: Set a watchpoint (breakpoint) for an expression.
4705 info watchpoints: Information about your watchpoints.
4707 delete N: Deletes watchpoint number N (same as breakpoints).
4708 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4709 enable N: Re-enables watchpoint number N (same as breakpoints).
4712 * C++ multiple inheritance
4714 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4717 * C++ exception handling
4719 Gdb now supports limited C++ exception handling. Besides the existing
4720 ability to breakpoint on an exception handler, gdb can breakpoint on
4721 the raising of an exception (before the stack is peeled back to the
4724 catch FOO: If there is a FOO exception handler in the dynamic scope,
4725 set a breakpoint to catch exceptions which may be raised there.
4726 Multiple exceptions (``catch foo bar baz'') may be caught.
4728 info catch: Lists all exceptions which may be caught in the
4729 current stack frame.
4732 * Minor command changes
4734 The command ``call func (arg, arg, ...)'' now acts like the print
4735 command, except it does not print or save a value if the function's result
4736 is void. This is similar to dbx usage.
4738 The ``up'' and ``down'' commands now always print the frame they end up
4739 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4740 frames without printing.
4742 * New directory command
4744 'dir' now adds directories to the FRONT of the source search path.
4745 The path starts off empty. Source files that contain debug information
4746 about the directory in which they were compiled can be found even
4747 with an empty path; Sun CC and GCC include this information. If GDB can't
4748 find your source file in the current directory, type "dir .".
4750 * Configuring GDB for compilation
4752 For normal use, type ``./configure host''. See README or gdb.texinfo
4755 GDB now handles cross debugging. If you are remotely debugging between
4756 two different machines, type ``./configure host -target=targ''.
4757 Host is the machine where GDB will run; targ is the machine
4758 where the program that you are debugging will run.