1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 8.1
6 * 'info proc' now works on running processes on FreeBSD systems and core
7 files created on FreeBSD systems.
11 * GDB now supports dynamically creating arbitrary register groups specified
12 in XML target descriptions. This allows for finer grain grouping of
13 registers on systems with a large amount of registers.
15 * The 'ptype' command now accepts a '/o' flag, which prints the
16 offsets and sizes of fields in a struct, like the pahole(1) tool.
18 * New "--readnever" command line option instructs GDB to not read each
19 symbol file's symbolic debug information. This makes startup faster
20 but at the expense of not being able to perform symbolic debugging.
21 This option is intended for use cases where symbolic debugging will
22 not be used, e.g., when you only need to dump the debuggee's core.
24 * GDB now uses the GNU MPFR library, if available, to emulate target
25 floating-point arithmetic during expression evaluation when the target
26 uses different floating-point formats than the host. At least version
27 3.1 of GNU MPFR is required.
29 * GDB now supports access to the guarded-storage-control registers and the
30 software-based guarded-storage broadcast control registers on IBM z14.
32 * On Unix systems, GDB now supports transmitting environment variables
33 that are to be set or unset to GDBserver. These variables will
34 affect the environment to be passed to the remote inferior.
36 To inform GDB of environment variables that are to be transmitted to
37 GDBserver, use the "set environment" command. Only user set
38 environment variables are sent to GDBserver.
40 To inform GDB of environment variables that are to be unset before
41 the remote inferior is started by the GDBserver, use the "unset
44 * Completion improvements
46 ** GDB can now complete function parameters in linespecs and
47 explicit locations without quoting. When setting breakpoints,
48 quoting around functions names to help with TAB-completion is
49 generally no longer necessary. For example, this now completes
52 (gdb) b function(in[TAB]
55 Related, GDB is no longer confused with completing functions in
56 C++ anonymous namespaces:
59 (gdb) b (anonymous namespace)::[TAB][TAB]
60 (anonymous namespace)::a_function()
61 (anonymous namespace)::b_function()
63 ** GDB now has much improved linespec and explicit locations TAB
64 completion support, that better understands what you're
65 completing and offers better suggestions. For example, GDB no
66 longer offers data symbols as possible completions when you're
69 ** GDB now TAB-completes label symbol names.
71 ** The "complete" command now mimics TAB completion accurately.
73 * New command line options (gcore)
76 Dump all memory mappings.
78 * Breakpoints on C++ functions are now set on all scopes by default
80 By default, breakpoints on functions/methods are now interpreted as
81 specifying all functions with the given name ignoring missing
82 leading scopes (namespaces and classes).
84 For example, assuming a C++ program with symbols named:
89 both commands "break func()" and "break B::func()" set a breakpoint
92 You can use the new flag "-qualified" to override this. This makes
93 GDB interpret the specified function name as a complete
94 fully-qualified name instead. For example, using the same C++
95 program, the "break -q B::func" command sets a breakpoint on
96 "B::func", only. A parameter has been added to the Python
97 gdb.Breakpoint constructor to achieve the same result when creating
98 a breakpoint from Python.
100 * Breakpoints on functions marked with C++ ABI tags
102 GDB can now set breakpoints on functions marked with C++ ABI tags
103 (e.g., [abi:cxx11]). See here for a description of ABI tags:
104 https://developers.redhat.com/blog/2015/02/05/gcc5-and-the-c11-abi/
106 Functions with a C++11 abi tag are demangled/displayed like this:
108 function[abi:cxx11](int)
111 You can now set a breakpoint on such functions simply as if they had
114 (gdb) b function(int)
116 Or if you need to disambiguate between tags, like:
118 (gdb) b function[abi:other_tag](int)
120 Tab completion was adjusted accordingly as well.
124 ** New events gdb.new_inferior, gdb.inferior_deleted, and
125 gdb.new_thread are emitted. See the manual for further
126 description of these.
128 ** A new command, "rbreak" has been added to the Python API. This
129 command allows the setting of a large number of breakpoints via a
130 regex pattern in Python. See the manual for further details.
132 ** Python breakpoints can now accept explicit locations. See the
133 manual for a further description of this feature.
136 * New features in the GDB remote stub, GDBserver
138 ** GDBserver is now able to start inferior processes with a
139 specified initial working directory.
141 The user can set the desired working directory to be used from
142 GDB using the new "set cwd" command.
144 ** New "--selftest" command line option runs some GDBserver self
145 tests. These self tests are disabled in releases.
147 ** On Unix systems, GDBserver now does globbing expansion and variable
148 substitution in inferior command line arguments.
150 This is done by starting inferiors using a shell, like GDB does.
151 See "set startup-with-shell" in the user manual for how to disable
152 this from GDB when using "target extended-remote". When using
153 "target remote", you can disable the startup with shell by using the
154 new "--no-startup-with-shell" GDBserver command line option.
156 ** On Unix systems, GDBserver now supports receiving environment
157 variables that are to be set or unset from GDB. These variables
158 will affect the environment to be passed to the inferior.
160 * When catching an Ada exception raised with a message, GDB now prints
161 the message in the catchpoint hit notification. In GDB/MI mode, that
162 information is provided as an extra field named "exception-message"
163 in the *stopped notification.
165 * Trait objects can now be inspected When debugging Rust code. This
166 requires compiler support which will appear in Rust 1.24.
170 QEnvironmentHexEncoded
171 Inform GDBserver of an environment variable that is to be passed to
172 the inferior when starting it.
175 Inform GDBserver of an environment variable that is to be unset
176 before starting the remote inferior.
179 Inform GDBserver that the environment should be reset (i.e.,
180 user-set environment variables should be unset).
183 Indicates whether the inferior must be started with a shell or not.
186 Tell GDBserver that the inferior to be started should use a specific
189 * The "maintenance print c-tdesc" command now takes an optional
190 argument which is the file name of XML target description.
192 * The "maintenance selftest" command now takes an optional argument to
193 filter the tests to be run.
195 * The "enable", and "disable" commands now accept a range of
196 breakpoint locations, e.g. "enable 1.3-5".
201 Set and show the current working directory for the inferior.
204 Set and show compilation command used for compiling and injecting code
205 with the 'compile' commands.
207 set debug separate-debug-file
208 show debug separate-debug-file
209 Control the display of debug output about separate debug file search.
211 set dump-excluded-mappings
212 show dump-excluded-mappings
213 Control whether mappings marked with the VM_DONTDUMP flag should be
214 dumped when generating a core file.
217 List the registered selftests.
220 Start the debugged program stopping at the first instruction.
223 Control display of debugging messages related to OpenRISC targets.
225 set|show print type nested-type-limit
226 Set and show the limit of nesting level for nested types that the
227 type printer will show.
229 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
232 * Safer/improved support for debugging with no debug info
234 GDB no longer assumes functions with no debug information return
237 This means that GDB now refuses to call such functions unless you
238 tell it the function's type, by either casting the call to the
239 declared return type, or by casting the function to a function
240 pointer of the right type, and calling that:
242 (gdb) p getenv ("PATH")
243 'getenv' has unknown return type; cast the call to its declared return type
244 (gdb) p (char *) getenv ("PATH")
245 $1 = 0x7fffffffe "/usr/local/bin:/"...
246 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
247 $2 = 0x7fffffffe "/usr/local/bin:/"...
249 Similarly, GDB no longer assumes that global variables with no debug
250 info have type 'int', and refuses to print the variable's value
251 unless you tell it the variable's type:
254 'var' has unknown type; cast it to its declared type
258 * New native configurations
260 FreeBSD/aarch64 aarch64*-*-freebsd*
261 FreeBSD/arm arm*-*-freebsd*
265 FreeBSD/aarch64 aarch64*-*-freebsd*
266 FreeBSD/arm arm*-*-freebsd*
267 OpenRISC ELF or1k*-*-elf
269 * Removed targets and native configurations
271 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
273 *** Changes in GDB 8.0
275 * GDB now supports access to the PKU register on GNU/Linux. The register is
276 added by the Memory Protection Keys for Userspace feature which will be
277 available in future Intel CPUs.
279 * GDB now supports C++11 rvalue references.
283 ** New functions to start, stop and access a running btrace recording.
284 ** Rvalue references are now supported in gdb.Type.
286 * GDB now supports recording and replaying rdrand and rdseed Intel 64
289 * Building GDB and GDBserver now requires a C++11 compiler.
291 For example, GCC 4.8 or later.
293 It is no longer possible to build GDB or GDBserver with a C
294 compiler. The --disable-build-with-cxx configure option has been
297 * Building GDB and GDBserver now requires GNU make >= 3.81.
299 It is no longer supported to build GDB or GDBserver with another
300 implementation of the make program or an earlier version of GNU make.
302 * Native debugging on MS-Windows supports command-line redirection
304 Command-line arguments used for starting programs on MS-Windows can
305 now include redirection symbols supported by native Windows shells,
306 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
307 as "run", "start", and "set args", as well as the corresponding MI
310 * Support for thread names on MS-Windows.
312 GDB now catches and handles the special exception that programs
313 running on MS-Windows use to assign names to threads in the
316 * Support for Java programs compiled with gcj has been removed.
318 * User commands now accept an unlimited number of arguments.
319 Previously, only up to 10 was accepted.
321 * The "eval" command now expands user-defined command arguments.
323 This makes it easier to process a variable number of arguments:
328 eval "print $arg%d", $i
333 * Target descriptions can now describe registers for sparc32 and sparc64.
335 * GDB now supports DWARF version 5 (debug information format).
336 Its .debug_names index is not yet supported.
338 * New native configurations
340 FreeBSD/mips mips*-*-freebsd
344 Synopsys ARC arc*-*-elf32
345 FreeBSD/mips mips*-*-freebsd
347 * Removed targets and native configurations
349 Alpha running FreeBSD alpha*-*-freebsd*
350 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
355 Erases all the flash memory regions reported by the target.
357 maint print arc arc-instruction address
358 Print internal disassembler information about instruction at a given address.
362 set disassembler-options
363 show disassembler-options
364 Controls the passing of target specific information to the disassembler.
365 If it is necessary to specify more than one disassembler option then
366 multiple options can be placed together into a comma separated list.
367 The default value is the empty string. Currently, the only supported
368 targets are ARM, PowerPC and S/390.
373 Erases all the flash memory regions reported by the target. This is
374 equivalent to the CLI command flash-erase.
376 -file-list-shared-libraries
377 List the shared libraries in the program. This is
378 equivalent to the CLI command "info shared".
381 Catchpoints stopping the program when Ada exceptions are
382 handled. This is equivalent to the CLI command "catch handlers".
384 *** Changes in GDB 7.12
386 * GDB and GDBserver now build with a C++ compiler by default.
388 The --enable-build-with-cxx configure option is now enabled by
389 default. One must now explicitly configure with
390 --disable-build-with-cxx in order to build with a C compiler. This
391 option will be removed in a future release.
393 * GDBserver now supports recording btrace without maintaining an active
396 * GDB now supports a negative repeat count in the 'x' command to examine
397 memory backward from the given address. For example:
400 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
401 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
402 (gdb) x/-5i 0x0000000000400580
403 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
404 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
405 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
406 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
407 0x40057b <main(int, char**)+25>:
408 callq 0x400536 <Func1(int, char const*)>
410 * Fortran: Support structures with fields of dynamic types and
411 arrays of dynamic types.
413 * The symbol dumping maintenance commands have new syntax.
414 maint print symbols [-pc address] [--] [filename]
415 maint print symbols [-objfile objfile] [-source source] [--] [filename]
416 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
417 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
418 maint print msymbols [-objfile objfile] [--] [filename]
420 * GDB now supports multibit bitfields and enums in target register
423 * New Python-based convenience function $_as_string(val), which returns
424 the textual representation of a value. This function is especially
425 useful to obtain the text label of an enum value.
427 * Intel MPX bound violation handling.
429 Segmentation faults caused by a Intel MPX boundary violation
430 now display the kind of violation (upper or lower), the memory
431 address accessed and the memory bounds, along with the usual
432 signal received and code location.
436 Program received signal SIGSEGV, Segmentation fault
437 Upper bound violation while accessing address 0x7fffffffc3b3
438 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
439 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
441 * Rust language support.
442 GDB now supports debugging programs written in the Rust programming
443 language. See https://www.rust-lang.org/ for more information about
446 * Support for running interpreters on specified input/output devices
448 GDB now supports a new mechanism that allows frontends to provide
449 fully featured GDB console views, as a better alternative to
450 building such views on top of the "-interpreter-exec console"
451 command. See the new "new-ui" command below. With that command,
452 frontends can now start GDB in the traditional command-line mode
453 running in an embedded terminal emulator widget, and create a
454 separate MI interpreter running on a specified i/o device. In this
455 way, GDB handles line editing, history, tab completion, etc. in the
456 console all by itself, and the GUI uses the separate MI interpreter
457 for its own control and synchronization, invisible to the command
460 * The "catch syscall" command catches groups of related syscalls.
462 The "catch syscall" command now supports catching a group of related
463 syscalls using the 'group:' or 'g:' prefix.
468 skip -gfile file-glob-pattern
469 skip -function function
470 skip -rfunction regular-expression
471 A generalized form of the skip command, with new support for
472 glob-style file names and regular expressions for function names.
473 Additionally, a file spec and a function spec may now be combined.
475 maint info line-table REGEXP
476 Display the contents of GDB's internal line table data struture.
479 Run any GDB unit tests that were compiled in.
482 Start a new user interface instance running INTERP as interpreter,
483 using the TTY file for input/output.
487 ** gdb.Breakpoint objects have a new attribute "pending", which
488 indicates whether the breakpoint is pending.
489 ** Three new breakpoint-related events have been added:
490 gdb.breakpoint_created, gdb.breakpoint_modified, and
491 gdb.breakpoint_deleted.
494 Signal ("set") the given MS-Windows event object. This is used in
495 conjunction with the Windows JIT debugging (AeDebug) support, where
496 the OS suspends a crashing process until a debugger can attach to
497 it. Resuming the crashing process, in order to debug it, is done by
500 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
501 was added in GDBserver, including JIT compiling fast tracepoint's
502 conditional expression bytecode into native code.
504 * Support for various remote target protocols and ROM monitors has
507 target m32rsdi Remote M32R debugging over SDI
508 target mips MIPS remote debugging protocol
509 target pmon PMON ROM monitor
510 target ddb NEC's DDB variant of PMON for Vr4300
511 target rockhopper NEC RockHopper variant of PMON
512 target lsi LSI variant of PMO
514 * Support for tracepoints and fast tracepoints on powerpc-linux,
515 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
516 including JIT compiling fast tracepoint's conditional expression
517 bytecode into native code.
519 * MI async record =record-started now includes the method and format used for
520 recording. For example:
522 =record-started,thread-group="i1",method="btrace",format="bts"
524 * MI async record =thread-selected now includes the frame field. For example:
526 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
530 Andes NDS32 nds32*-*-elf
532 *** Changes in GDB 7.11
534 * GDB now supports debugging kernel-based threads on FreeBSD.
536 * Per-inferior thread numbers
538 Thread numbers are now per inferior instead of global. If you're
539 debugging multiple inferiors, GDB displays thread IDs using a
540 qualified INF_NUM.THR_NUM form. For example:
544 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
545 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
546 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
547 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
549 As consequence, thread numbers as visible in the $_thread
550 convenience variable and in Python's InferiorThread.num attribute
551 are no longer unique between inferiors.
553 GDB now maintains a second thread ID per thread, referred to as the
554 global thread ID, which is the new equivalent of thread numbers in
555 previous releases. See also $_gthread below.
557 For backwards compatibility, MI's thread IDs always refer to global
560 * Commands that accept thread IDs now accept the qualified
561 INF_NUM.THR_NUM form as well. For example:
564 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
567 * In commands that accept a list of thread IDs, you can now refer to
568 all threads of an inferior using a star wildcard. GDB accepts
569 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
570 refer to all threads of the current inferior. For example, "info
573 * You can use "info threads -gid" to display the global thread ID of
576 * The new convenience variable $_gthread holds the global number of
579 * The new convenience variable $_inferior holds the number of the
582 * GDB now displays the ID and name of the thread that hit a breakpoint
583 or received a signal, if your program is multi-threaded. For
586 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
587 Thread 1 "main" received signal SIGINT, Interrupt.
589 * Record btrace now supports non-stop mode.
591 * Support for tracepoints on aarch64-linux was added in GDBserver.
593 * The 'record instruction-history' command now indicates speculative execution
594 when using the Intel Processor Trace recording format.
596 * GDB now allows users to specify explicit locations, bypassing
597 the linespec parser. This feature is also available to GDB/MI
600 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
601 GDB now is able to debug both AArch64 applications and ARM applications
604 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
605 including JIT compiling fast tracepoint's conditional expression bytecode
608 * GDB now supports displaced stepping on AArch64 GNU/Linux.
610 * "info threads", "info inferiors", "info display", "info checkpoints"
611 and "maint info program-spaces" now list the corresponding items in
612 ascending ID order, for consistency with all other "info" commands.
614 * In Ada, the overloads selection menu has been enhanced to display the
615 parameter types and the return types for the matching overloaded subprograms.
619 maint set target-non-stop (on|off|auto)
620 maint show target-non-stop
621 Control whether GDB targets always operate in non-stop mode even if
622 "set non-stop" is "off". The default is "auto", meaning non-stop
623 mode is enabled if supported by the target.
625 maint set bfd-sharing
626 maint show bfd-sharing
627 Control the reuse of bfd objects.
631 Control display of debugging info regarding bfd caching.
635 Control display of debugging info regarding FreeBSD threads.
637 set remote multiprocess-extensions-packet
638 show remote multiprocess-extensions-packet
639 Set/show the use of the remote protocol multiprocess extensions.
641 set remote thread-events
642 show remote thread-events
643 Set/show the use of thread create/exit events.
645 set ada print-signatures on|off
646 show ada print-signatures"
647 Control whether parameter types and return types are displayed in overloads
648 selection menus. It is activaled (@code{on}) by default.
652 Controls the maximum size of memory, in bytes, that GDB will
653 allocate for value contents. Prevents incorrect programs from
654 causing GDB to allocate overly large buffers. Default is 64k.
656 * The "disassemble" command accepts a new modifier: /s.
657 It prints mixed source+disassembly like /m with two differences:
658 - disassembled instructions are now printed in program order, and
659 - and source for all relevant files is now printed.
660 The "/m" option is now considered deprecated: its "source-centric"
661 output hasn't proved useful in practice.
663 * The "record instruction-history" command accepts a new modifier: /s.
664 It behaves exactly like /m and prints mixed source+disassembly.
666 * The "set scheduler-locking" command supports a new mode "replay".
667 It behaves like "off" in record mode and like "on" in replay mode.
669 * Support for various ROM monitors has been removed:
671 target dbug dBUG ROM monitor for Motorola ColdFire
672 target picobug Motorola picobug monitor
673 target dink32 DINK32 ROM monitor for PowerPC
674 target m32r Renesas M32R/D ROM monitor
675 target mon2000 mon2000 ROM monitor
676 target ppcbug PPCBUG ROM monitor for PowerPC
678 * Support for reading/writing memory and extracting values on architectures
679 whose memory is addressable in units of any integral multiple of 8 bits.
682 Allows to break when an Ada exception is handled.
687 Indicates that an exec system call was executed.
689 exec-events feature in qSupported
690 The qSupported packet allows GDB to request support for exec
691 events using the new 'gdbfeature' exec-event, and the qSupported
692 response can contain the corresponding 'stubfeature'. Set and
693 show commands can be used to display whether these features are enabled.
696 Equivalent to interrupting with the ^C character, but works in
699 thread created stop reason (T05 create:...)
700 Indicates that the thread was just created and is stopped at entry.
702 thread exit stop reply (w exitcode;tid)
703 Indicates that the thread has terminated.
706 Enables/disables thread create and exit event reporting. For
707 example, this is used in non-stop mode when GDB stops a set of
708 threads and synchronously waits for the their corresponding stop
709 replies. Without exit events, if one of the threads exits, GDB
710 would hang forever not knowing that it should no longer expect a
711 stop for that same thread.
714 Indicates that there are no resumed threads left in the target (all
715 threads are stopped). The remote stub reports support for this stop
716 reply to GDB's qSupported query.
719 Enables/disables catching syscalls from the inferior process.
720 The remote stub reports support for this packet to GDB's qSupported query.
722 syscall_entry stop reason
723 Indicates that a syscall was just called.
725 syscall_return stop reason
726 Indicates that a syscall just returned.
728 * Extended-remote exec events
730 ** GDB now has support for exec events on extended-remote Linux targets.
731 For such targets with Linux kernels 2.5.46 and later, this enables
732 follow-exec-mode and exec catchpoints.
734 set remote exec-event-feature-packet
735 show remote exec-event-feature-packet
736 Set/show the use of the remote exec event feature.
738 * Thread names in remote protocol
740 The reply to qXfer:threads:read may now include a name attribute for each
743 * Target remote mode fork and exec events
745 ** GDB now has support for fork and exec events on target remote mode
746 Linux targets. For such targets with Linux kernels 2.5.46 and later,
747 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
748 fork and exec catchpoints.
750 * Remote syscall events
752 ** GDB now has support for catch syscall on remote Linux targets,
753 currently enabled on x86/x86_64 architectures.
755 set remote catch-syscall-packet
756 show remote catch-syscall-packet
757 Set/show the use of the remote catch syscall feature.
761 ** The -var-set-format command now accepts the zero-hexadecimal
762 format. It outputs data in hexadecimal format with zero-padding on the
767 ** gdb.InferiorThread objects have a new attribute "global_num",
768 which refers to the thread's global thread ID. The existing
769 "num" attribute now refers to the thread's per-inferior number.
770 See "Per-inferior thread numbers" above.
771 ** gdb.InferiorThread objects have a new attribute "inferior", which
772 is the Inferior object the thread belongs to.
774 *** Changes in GDB 7.10
776 * Support for process record-replay and reverse debugging on aarch64*-linux*
777 targets has been added. GDB now supports recording of A64 instruction set
778 including advance SIMD instructions.
780 * Support for Sun's version of the "stabs" debug file format has been removed.
782 * GDB now honors the content of the file /proc/PID/coredump_filter
783 (PID is the process ID) on GNU/Linux systems. This file can be used
784 to specify the types of memory mappings that will be included in a
785 corefile. For more information, please refer to the manual page of
786 "core(5)". GDB also has a new command: "set use-coredump-filter
787 on|off". It allows to set whether GDB will read the content of the
788 /proc/PID/coredump_filter file when generating a corefile.
790 * The "info os" command on GNU/Linux can now display information on
792 "info os cpus" Listing of all cpus/cores on the system
794 * GDB has two new commands: "set serial parity odd|even|none" and
795 "show serial parity". These allows to set or show parity for the
798 * The "info source" command now displays the producer string if it was
799 present in the debug info. This typically includes the compiler version
800 and may include things like its command line arguments.
802 * The "info dll", an alias of the "info sharedlibrary" command,
803 is now available on all platforms.
805 * Directory names supplied to the "set sysroot" commands may be
806 prefixed with "target:" to tell GDB to access shared libraries from
807 the target system, be it local or remote. This replaces the prefix
808 "remote:". The default sysroot has been changed from "" to
809 "target:". "remote:" is automatically converted to "target:" for
810 backward compatibility.
812 * The system root specified by "set sysroot" will be prepended to the
813 filename of the main executable (if reported to GDB as absolute by
814 the operating system) when starting processes remotely, and when
815 attaching to already-running local or remote processes.
817 * GDB now supports automatic location and retrieval of executable
818 files from remote targets. Remote debugging can now be initiated
819 using only a "target remote" or "target extended-remote" command
820 (no "set sysroot" or "file" commands are required). See "New remote
823 * The "dump" command now supports verilog hex format.
825 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
827 * On GNU/Linux, GDB and gdbserver are now able to access executable
828 and shared library files without a "set sysroot" command when
829 attaching to processes running in different mount namespaces from
830 the debugger. This makes it possible to attach to processes in
831 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
832 See "New remote packets" below.
834 * The "tui reg" command now provides completion for all of the
835 available register groups, including target specific groups.
837 * The HISTSIZE environment variable is no longer read when determining
838 the size of GDB's command history. GDB now instead reads the dedicated
839 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
840 disables truncation of command history. Non-numeric values of GDBHISTSIZE
845 ** Memory ports can now be unbuffered.
849 ** gdb.Objfile objects have a new attribute "username",
850 which is the name of the objfile as specified by the user,
851 without, for example, resolving symlinks.
852 ** You can now write frame unwinders in Python.
853 ** gdb.Type objects have a new method "optimized_out",
854 returning optimized out gdb.Value instance of this type.
855 ** gdb.Value objects have new methods "reference_value" and
856 "const_value" which return a reference to the value and a
857 "const" version of the value respectively.
861 maint print symbol-cache
862 Print the contents of the symbol cache.
864 maint print symbol-cache-statistics
865 Print statistics of symbol cache usage.
867 maint flush-symbol-cache
868 Flush the contents of the symbol cache.
872 Start branch trace recording using Branch Trace Store (BTS) format.
875 Evaluate expression by using the compiler and print result.
879 Explicit commands for enabling and disabling tui mode.
882 set mpx bound on i386 and amd64
883 Support for bound table investigation on Intel MPX enabled applications.
887 Start branch trace recording using Intel Processor Trace format.
890 Print information about branch tracing internals.
892 maint btrace packet-history
893 Print the raw branch tracing data.
895 maint btrace clear-packet-history
896 Discard the stored raw branch tracing data.
899 Discard all branch tracing data. It will be fetched and processed
900 anew by the next "record" command.
905 Renamed from "set debug dwarf2-die".
907 Renamed from "show debug dwarf2-die".
910 Renamed from "set debug dwarf2-read".
911 show debug dwarf-read
912 Renamed from "show debug dwarf2-read".
914 maint set dwarf always-disassemble
915 Renamed from "maint set dwarf2 always-disassemble".
916 maint show dwarf always-disassemble
917 Renamed from "maint show dwarf2 always-disassemble".
919 maint set dwarf max-cache-age
920 Renamed from "maint set dwarf2 max-cache-age".
921 maint show dwarf max-cache-age
922 Renamed from "maint show dwarf2 max-cache-age".
925 show debug dwarf-line
926 Control display of debugging info regarding DWARF line processing.
930 Set the maximum number of candidates to be considered during
931 completion. The default value is 200. This limit allows GDB
932 to avoid generating large completion lists, the computation of
933 which can cause the debugger to become temporarily unresponsive.
935 set history remove-duplicates
936 show history remove-duplicates
937 Control the removal of duplicate history entries.
939 maint set symbol-cache-size
940 maint show symbol-cache-size
941 Control the size of the symbol cache.
943 set|show record btrace bts buffer-size
944 Set and show the size of the ring buffer used for branch tracing in
946 The obtained size may differ from the requested size. Use "info
947 record" to see the obtained buffer size.
949 set debug linux-namespaces
950 show debug linux-namespaces
951 Control display of debugging info regarding Linux namespaces.
953 set|show record btrace pt buffer-size
954 Set and show the size of the ring buffer used for branch tracing in
955 Intel Processor Trace format.
956 The obtained size may differ from the requested size. Use "info
957 record" to see the obtained buffer size.
959 maint set|show btrace pt skip-pad
960 Set and show whether PAD packets are skipped when computing the
963 * The command 'thread apply all' can now support new option '-ascending'
964 to call its specified command for all threads in ascending order.
966 * Python/Guile scripting
968 ** GDB now supports auto-loading of Python/Guile scripts contained in the
969 special section named `.debug_gdb_scripts'.
973 qXfer:btrace-conf:read
974 Return the branch trace configuration for the current thread.
976 Qbtrace-conf:bts:size
977 Set the requested ring buffer size for branch tracing in BTS format.
980 Enable Intel Procesor Trace-based branch tracing for the current
981 process. The remote stub reports support for this packet to GDB's
985 Set the requested ring buffer size for branch tracing in Intel Processor
989 Indicates a memory breakpoint instruction was executed, irrespective
990 of whether it was GDB that planted the breakpoint or the breakpoint
991 is hardcoded in the program. This is required for correct non-stop
995 Indicates the target stopped for a hardware breakpoint. This is
996 required for correct non-stop mode operation.
999 Return information about files on the remote system.
1001 qXfer:exec-file:read
1002 Return the full absolute name of the file that was executed to
1003 create a process running on the remote system.
1006 Select the filesystem on which vFile: operations with filename
1007 arguments will operate. This is required for GDB to be able to
1008 access files on remote targets where the remote stub does not
1009 share a common filesystem with the inferior(s).
1012 Indicates that a fork system call was executed.
1015 Indicates that a vfork system call was executed.
1017 vforkdone stop reason
1018 Indicates that a vfork child of the specified process has executed
1019 an exec or exit, allowing the vfork parent to resume execution.
1021 fork-events and vfork-events features in qSupported
1022 The qSupported packet allows GDB to request support for fork and
1023 vfork events using new 'gdbfeatures' fork-events and vfork-events,
1024 and the qSupported response can contain the corresponding
1025 'stubfeatures'. Set and show commands can be used to display
1026 whether these features are enabled.
1028 * Extended-remote fork events
1030 ** GDB now has support for fork events on extended-remote Linux
1031 targets. For targets with Linux kernels 2.5.60 and later, this
1032 enables follow-fork-mode and detach-on-fork for both fork and
1033 vfork, as well as fork and vfork catchpoints.
1035 * The info record command now shows the recording format and the
1036 branch tracing configuration for the current thread when using
1037 the btrace record target.
1038 For the BTS format, it shows the ring buffer size.
1040 * GDB now has support for DTrace USDT (Userland Static Defined
1041 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
1043 * GDB now supports access to vector registers on S/390 GNU/Linux
1046 * Removed command line options
1048 -xdb HP-UX XDB compatibility mode.
1050 * Removed targets and native configurations
1052 HP/PA running HP-UX hppa*-*-hpux*
1053 Itanium running HP-UX ia64-*-hpux*
1055 * New configure options
1058 This configure option allows the user to build GDB with support for
1059 Intel Processor Trace (default: auto). This requires libipt.
1061 --with-libipt-prefix=PATH
1062 Specify the path to the version of libipt that GDB should use.
1063 $PATH/include should contain the intel-pt.h header and
1064 $PATH/lib should contain the libipt.so library.
1066 *** Changes in GDB 7.9.1
1070 ** Xmethods can now specify a result type.
1072 *** Changes in GDB 7.9
1074 * GDB now supports hardware watchpoints on x86 GNU Hurd.
1078 ** You can now access frame registers from Python scripts.
1079 ** New attribute 'producer' for gdb.Symtab objects.
1080 ** gdb.Objfile objects have a new attribute "progspace",
1081 which is the gdb.Progspace object of the containing program space.
1082 ** gdb.Objfile objects have a new attribute "owner".
1083 ** gdb.Objfile objects have a new attribute "build_id",
1084 which is the build ID generated when the file was built.
1085 ** gdb.Objfile objects have a new method "add_separate_debug_file".
1086 ** A new event "gdb.clear_objfiles" has been added, triggered when
1087 selecting a new file to debug.
1088 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
1089 ** New function gdb.lookup_objfile.
1091 New events which are triggered when GDB modifies the state of the
1094 ** gdb.events.inferior_call_pre: Function call is about to be made.
1095 ** gdb.events.inferior_call_post: Function call has just been made.
1096 ** gdb.events.memory_changed: A memory location has been altered.
1097 ** gdb.events.register_changed: A register has been altered.
1099 * New Python-based convenience functions:
1101 ** $_caller_is(name [, number_of_frames])
1102 ** $_caller_matches(regexp [, number_of_frames])
1103 ** $_any_caller_is(name [, number_of_frames])
1104 ** $_any_caller_matches(regexp [, number_of_frames])
1106 * GDB now supports the compilation and injection of source code into
1107 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
1108 to compile the source code to object code, and if successful, inject
1109 and execute that code within the current context of the inferior.
1110 Currently the C language is supported. The commands used to
1111 interface with this new feature are:
1113 compile code [-raw|-r] [--] [source code]
1114 compile file [-raw|-r] filename
1118 demangle [-l language] [--] name
1119 Demangle "name" in the specified language, or the current language
1120 if elided. This command is renamed from the "maint demangle" command.
1121 The latter is kept as a no-op to avoid "maint demangle" being interpreted
1122 as "maint demangler-warning".
1124 queue-signal signal-name-or-number
1125 Queue a signal to be delivered to the thread when it is resumed.
1127 add-auto-load-scripts-directory directory
1128 Add entries to the list of directories from which to load auto-loaded
1131 maint print user-registers
1132 List all currently available "user" registers.
1134 compile code [-r|-raw] [--] [source code]
1135 Compile, inject, and execute in the inferior the executable object
1136 code produced by compiling the provided source code.
1138 compile file [-r|-raw] filename
1139 Compile and inject into the inferior the executable object code
1140 produced by compiling the source code stored in the filename
1143 * On resume, GDB now always passes the signal the program had stopped
1144 for to the thread the signal was sent to, even if the user changed
1145 threads before resuming. Previously GDB would often (but not
1146 always) deliver the signal to the thread that happens to be current
1149 * Conversely, the "signal" command now consistently delivers the
1150 requested signal to the current thread. GDB now asks for
1151 confirmation if the program had stopped for a signal and the user
1152 switched threads meanwhile.
1154 * "breakpoint always-inserted" modes "off" and "auto" merged.
1156 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
1157 won't remove breakpoints from the target until all threads stop,
1158 even in non-stop mode. The "auto" mode has been removed, and "off"
1159 is now the default mode.
1163 set debug symbol-lookup
1164 show debug symbol-lookup
1165 Control display of debugging info regarding symbol lookup.
1169 ** The -list-thread-groups command outputs an exit-code field for
1170 inferiors that have exited.
1174 MIPS SDE mips*-sde*-elf*
1178 Support for these obsolete configurations has been removed.
1180 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
1181 SGI Irix-5.x mips-*-irix5*
1182 SGI Irix-6.x mips-*-irix6*
1183 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
1184 VAX running Ultrix vax-*-ultrix*
1186 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1187 and "assf"), have been removed. Use the "sharedlibrary" command, or
1188 its alias "share", instead.
1190 *** Changes in GDB 7.8
1192 * New command line options
1195 This is an alias for the --data-directory option.
1197 * GDB supports printing and modifying of variable length automatic arrays
1198 as specified in ISO C99.
1200 * The ARM simulator now supports instruction level tracing
1201 with or without disassembly.
1205 GDB now has support for scripting using Guile. Whether this is
1206 available is determined at configure time.
1207 Guile version 2.0 or greater is required.
1208 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
1210 * New commands (for set/show, see "New options" below)
1214 Invoke CODE by passing it to the Guile interpreter.
1218 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
1220 info auto-load guile-scripts [regexp]
1221 Print the list of automatically loaded Guile scripts.
1223 * The source command is now capable of sourcing Guile scripts.
1224 This feature is dependent on the debugger being built with Guile support.
1228 set print symbol-loading (off|brief|full)
1229 show print symbol-loading
1230 Control whether to print informational messages when loading symbol
1231 information for a file. The default is "full", but when debugging
1232 programs with large numbers of shared libraries the amount of output
1233 becomes less useful.
1235 set guile print-stack (none|message|full)
1236 show guile print-stack
1237 Show a stack trace when an error is encountered in a Guile script.
1239 set auto-load guile-scripts (on|off)
1240 show auto-load guile-scripts
1241 Control auto-loading of Guile script files.
1243 maint ada set ignore-descriptive-types (on|off)
1244 maint ada show ignore-descriptive-types
1245 Control whether the debugger should ignore descriptive types in Ada
1246 programs. The default is not to ignore the descriptive types. See
1247 the user manual for more details on descriptive types and the intended
1248 usage of this option.
1250 set auto-connect-native-target
1252 Control whether GDB is allowed to automatically connect to the
1253 native target for the run, attach, etc. commands when not connected
1254 to any target yet. See also "target native" below.
1256 set record btrace replay-memory-access (read-only|read-write)
1257 show record btrace replay-memory-access
1258 Control what memory accesses are allowed during replay.
1260 maint set target-async (on|off)
1261 maint show target-async
1262 This controls whether GDB targets operate in synchronous or
1263 asynchronous mode. Normally the default is asynchronous, if it is
1264 available; but this can be changed to more easily debug problems
1265 occurring only in synchronous mode.
1267 set mi-async (on|off)
1269 Control whether MI asynchronous mode is preferred. This supersedes
1270 "set target-async" of previous GDB versions.
1272 * "set target-async" is deprecated as a CLI option and is now an alias
1273 for "set mi-async" (only puts MI into async mode).
1275 * Background execution commands (e.g., "c&", "s&", etc.) are now
1276 possible ``out of the box'' if the target supports them. Previously
1277 the user would need to explicitly enable the possibility with the
1278 "set target-async on" command.
1280 * New features in the GDB remote stub, GDBserver
1282 ** New option --debug-format=option1[,option2,...] allows one to add
1283 additional text to each output. At present only timestamps
1284 are supported: --debug-format=timestamps.
1285 Timestamps can also be turned on with the
1286 "monitor set debug-format timestamps" command from GDB.
1288 * The 'record instruction-history' command now starts counting instructions
1289 at one. This also affects the instruction ranges reported by the
1290 'record function-call-history' command when given the /i modifier.
1292 * The command 'record function-call-history' supports a new modifier '/c' to
1293 indent the function names based on their call stack depth.
1294 The fields for the '/i' and '/l' modifier have been reordered.
1295 The source line range is now prefixed with 'at'.
1296 The instruction range is now prefixed with 'inst'.
1297 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1298 "record instruction-history" and "list" commands.
1300 * The ranges given as arguments to the 'record function-call-history' and
1301 'record instruction-history' commands are now inclusive.
1303 * The btrace record target now supports the 'record goto' command.
1304 For locations inside the execution trace, the back trace is computed
1305 based on the information stored in the execution trace.
1307 * The btrace record target supports limited reverse execution and replay.
1308 The target does not record data and therefore does not allow reading
1309 memory or registers.
1311 * The "catch syscall" command now works on s390*-linux* targets.
1313 * The "compare-sections" command is no longer specific to target
1314 remote. It now works with all targets.
1316 * All native targets are now consistently called "native".
1317 Consequently, the "target child", "target GNU", "target djgpp",
1318 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1319 commands have been replaced with "target native". The QNX/NTO port
1320 leaves the "procfs" target in place and adds a "native" target for
1321 consistency with other ports. The impact on users should be minimal
1322 as these commands previously either throwed an error, or were
1323 no-ops. The target's name is visible in the output of the following
1324 commands: "help target", "info target", "info files", "maint print
1327 * The "target native" command now connects to the native target. This
1328 can be used to launch native programs even when "set
1329 auto-connect-native-target" is set to off.
1331 * GDB now supports access to Intel MPX registers on GNU/Linux.
1333 * Support for Intel AVX-512 registers on GNU/Linux.
1334 Support displaying and modifying Intel AVX-512 registers
1335 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1337 * New remote packets
1339 qXfer:btrace:read's annex
1340 The qXfer:btrace:read packet supports a new annex 'delta' to read
1341 branch trace incrementally.
1345 ** Valid Python operations on gdb.Value objects representing
1346 structs/classes invoke the corresponding overloaded operators if
1348 ** New `Xmethods' feature in the Python API. Xmethods are
1349 additional methods or replacements for existing methods of a C++
1350 class. This feature is useful for those cases where a method
1351 defined in C++ source code could be inlined or optimized out by
1352 the compiler, making it unavailable to GDB.
1355 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1357 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1358 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1359 its alias "share", instead.
1361 * The commands "set remotebaud" and "show remotebaud" are no longer
1362 supported. Use "set serial baud" and "show serial baud" (respectively)
1367 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1368 target-async". The latter is left as a deprecated alias of the
1369 former for backward compatibility. If the target supports it,
1370 CLI background execution commands are now always possible by
1371 default, independently of whether the frontend stated a
1372 preference for asynchronous execution with "-gdb-set mi-async".
1373 Previously "-gdb-set target-async off" affected both MI execution
1374 commands and CLI execution commands.
1376 *** Changes in GDB 7.7
1378 * Improved support for process record-replay and reverse debugging on
1379 arm*-linux* targets. Support for thumb32 and syscall instruction
1380 recording has been added.
1382 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1384 * GDB now supports Fission DWP file format version 2.
1385 http://gcc.gnu.org/wiki/DebugFission
1387 * New convenience function "$_isvoid", to check whether an expression
1388 is void. A void expression is an expression where the type of the
1389 result is "void". For example, some convenience variables may be
1390 "void" when evaluated (e.g., "$_exitcode" before the execution of
1391 the program being debugged; or an undefined convenience variable).
1392 Another example, when calling a function whose return type is
1395 * The "maintenance print objfiles" command now takes an optional regexp.
1397 * The "catch syscall" command now works on arm*-linux* targets.
1399 * GDB now consistently shows "<not saved>" when printing values of
1400 registers the debug info indicates have not been saved in the frame
1401 and there's nowhere to retrieve them from
1402 (callee-saved/call-clobbered registers):
1407 (gdb) info registers rax
1410 Before, the former would print "<optimized out>", and the latter
1411 "*value not available*".
1413 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1418 ** Frame filters and frame decorators have been added.
1419 ** Temporary breakpoints are now supported.
1420 ** Line tables representation has been added.
1421 ** New attribute 'parent_type' for gdb.Field objects.
1422 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1423 ** New attribute 'name' for gdb.Type objects.
1427 Nios II ELF nios2*-*-elf
1428 Nios II GNU/Linux nios2*-*-linux
1429 Texas Instruments MSP430 msp430*-*-elf
1431 * Removed native configurations
1433 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1434 been removed. ELF variants of these configurations are kept supported.
1436 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1437 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1438 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1439 i[34567]86-*-openbsd3.[0-3]
1440 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1441 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1442 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1446 Like "catch throw", but catches a re-thrown exception.
1447 maint check-psymtabs
1448 Renamed from old "maint check-symtabs".
1450 Perform consistency checks on symtabs.
1451 maint expand-symtabs
1452 Expand symtabs matching an optional regexp.
1455 Display the details of GDB configure-time options.
1457 maint set|show per-command
1458 maint set|show per-command space
1459 maint set|show per-command time
1460 maint set|show per-command symtab
1461 Enable display of per-command gdb resource usage.
1463 remove-symbol-file FILENAME
1464 remove-symbol-file -a ADDRESS
1465 Remove a symbol file added via add-symbol-file. The file to remove
1466 can be identified by its filename or by an address that lies within
1467 the boundaries of this symbol file in memory.
1470 info exceptions REGEXP
1471 Display the list of Ada exceptions defined in the program being
1472 debugged. If provided, only the exceptions whose names match REGEXP
1477 set debug symfile off|on
1479 Control display of debugging info regarding reading symbol files and
1480 symbol tables within those files
1482 set print raw frame-arguments
1483 show print raw frame-arguments
1484 Set/show whether to print frame arguments in raw mode,
1485 disregarding any defined pretty-printers.
1487 set remote trace-status-packet
1488 show remote trace-status-packet
1489 Set/show the use of remote protocol qTStatus packet.
1493 Control display of debugging messages related to Nios II targets.
1497 Control whether target-assisted range stepping is enabled.
1499 set startup-with-shell
1500 show startup-with-shell
1501 Specifies whether Unix child processes are started via a shell or
1506 Use the target memory cache for accesses to the code segment. This
1507 improves performance of remote debugging (particularly disassembly).
1509 * You can now use a literal value 'unlimited' for options that
1510 interpret 0 or -1 as meaning "unlimited". E.g., "set
1511 trace-buffer-size unlimited" is now an alias for "set
1512 trace-buffer-size -1" and "set height unlimited" is now an alias for
1515 * The "set debug symtab-create" debugging option of GDB has been changed to
1516 accept a verbosity level. 0 means "off", 1 provides basic debugging
1517 output, and values of 2 or greater provides more verbose output.
1519 * New command-line options
1521 Display the details of GDB configure-time options.
1523 * The command 'tsave' can now support new option '-ctf' to save trace
1524 buffer in Common Trace Format.
1526 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1529 * GDB now implements the the C++ 'typeid' operator.
1531 * The new convenience variable $_exception holds the exception being
1532 thrown or caught at an exception-related catchpoint.
1534 * The exception-related catchpoints, like "catch throw", now accept a
1535 regular expression which can be used to filter exceptions by type.
1537 * The new convenience variable $_exitsignal is automatically set to
1538 the terminating signal number when the program being debugged dies
1539 due to an uncaught signal.
1543 ** All MI commands now accept an optional "--language" option.
1544 Support for this feature can be verified by using the "-list-features"
1545 command, which should contain "language-option".
1547 ** The new command -info-gdb-mi-command allows the user to determine
1548 whether a GDB/MI command is supported or not.
1550 ** The "^error" result record returned when trying to execute an undefined
1551 GDB/MI command now provides a variable named "code" whose content is the
1552 "undefined-command" error code. Support for this feature can be verified
1553 by using the "-list-features" command, which should contain
1554 "undefined-command-error-code".
1556 ** The -trace-save MI command can optionally save trace buffer in Common
1559 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1561 ** The command -data-list-register-values now accepts an optional
1562 "--skip-unavailable" option. When used, only the available registers
1565 ** The new command -trace-frame-collected dumps collected variables,
1566 computed expressions, tvars, memory and registers in a traceframe.
1568 ** The commands -stack-list-locals, -stack-list-arguments and
1569 -stack-list-variables now accept an option "--skip-unavailable".
1570 When used, only the available locals or arguments are displayed.
1572 ** The -exec-run command now accepts an optional "--start" option.
1573 When used, the command follows the same semantics as the "start"
1574 command, stopping the program's execution at the start of its
1575 main subprogram. Support for this feature can be verified using
1576 the "-list-features" command, which should contain
1577 "exec-run-start-option".
1579 ** The new commands -catch-assert and -catch-exceptions insert
1580 catchpoints stopping the program when Ada exceptions are raised.
1582 ** The new command -info-ada-exceptions provides the equivalent of
1583 the new "info exceptions" command.
1585 * New system-wide configuration scripts
1586 A GDB installation now provides scripts suitable for use as system-wide
1587 configuration scripts for the following systems:
1591 * GDB now supports target-assigned range stepping with remote targets.
1592 This improves the performance of stepping source lines by reducing
1593 the number of control packets from/to GDB. See "New remote packets"
1596 * GDB now understands the element 'tvar' in the XML traceframe info.
1597 It has the id of the collected trace state variables.
1599 * On S/390 targets that provide the transactional-execution feature,
1600 the program interruption transaction diagnostic block (TDB) is now
1601 represented as a number of additional "registers" in GDB.
1603 * New remote packets
1607 The vCont packet supports a new 'r' action, that tells the remote
1608 stub to step through an address range itself, without GDB
1609 involvemement at each single-step.
1611 qXfer:libraries-svr4:read's annex
1612 The previously unused annex of the qXfer:libraries-svr4:read packet
1613 is now used to support passing an argument list. The remote stub
1614 reports support for this argument list to GDB's qSupported query.
1615 The defined arguments are "start" and "prev", used to reduce work
1616 necessary for library list updating, resulting in significant
1619 * New features in the GDB remote stub, GDBserver
1621 ** GDBserver now supports target-assisted range stepping. Currently
1622 enabled on x86/x86_64 GNU/Linux targets.
1624 ** GDBserver now adds element 'tvar' in the XML in the reply to
1625 'qXfer:traceframe-info:read'. It has the id of the collected
1626 trace state variables.
1628 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1631 * New 'z' formatter for printing and examining memory, this displays the
1632 value as hexadecimal zero padded on the left to the size of the type.
1634 * GDB can now use Windows x64 unwinding data.
1636 * The "set remotebaud" command has been replaced by "set serial baud".
1637 Similarly, "show remotebaud" has been replaced by "show serial baud".
1638 The "set remotebaud" and "show remotebaud" commands are still available
1639 to provide backward compatibility with older versions of GDB.
1641 *** Changes in GDB 7.6
1643 * Target record has been renamed to record-full.
1644 Record/replay is now enabled with the "record full" command.
1645 This also affects settings that are associated with full record/replay
1646 that have been moved from "set/show record" to "set/show record full":
1648 set|show record full insn-number-max
1649 set|show record full stop-at-limit
1650 set|show record full memory-query
1652 * A new record target "record-btrace" has been added. The new target
1653 uses hardware support to record the control-flow of a process. It
1654 does not support replaying the execution, but it implements the
1655 below new commands for investigating the recorded execution log.
1656 This new recording method can be enabled using:
1660 The "record-btrace" target is only available on Intel Atom processors
1661 and requires a Linux kernel 2.6.32 or later.
1663 * Two new commands have been added for record/replay to give information
1664 about the recorded execution without having to replay the execution.
1665 The commands are only supported by "record btrace".
1667 record instruction-history prints the execution history at
1668 instruction granularity
1670 record function-call-history prints the execution history at
1671 function granularity
1673 * New native configurations
1675 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1676 FreeBSD/powerpc powerpc*-*-freebsd
1677 x86_64/Cygwin x86_64-*-cygwin*
1678 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1682 ARM AArch64 aarch64*-*-elf
1683 ARM AArch64 GNU/Linux aarch64*-*-linux
1684 Lynx 178 PowerPC powerpc-*-lynx*178
1685 x86_64/Cygwin x86_64-*-cygwin*
1686 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1688 * If the configured location of system.gdbinit file (as given by the
1689 --with-system-gdbinit option at configure time) is in the
1690 data-directory (as specified by --with-gdb-datadir at configure
1691 time) or in one of its subdirectories, then GDB will look for the
1692 system-wide init file in the directory specified by the
1693 --data-directory command-line option.
1695 * New command line options:
1697 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1698 other initialization files, unlike -nx which disables all of them.
1700 * Removed command line options
1702 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1705 * The 'ptype' and 'whatis' commands now accept an argument to control
1708 * 'info proc' now works on some core files.
1712 ** Vectors can be created with gdb.Type.vector.
1714 ** Python's atexit.register now works in GDB.
1716 ** Types can be pretty-printed via a Python API.
1718 ** Python 3 is now supported (in addition to Python 2.4 or later)
1720 ** New class gdb.Architecture exposes GDB's internal representation
1721 of architecture in the Python API.
1723 ** New method Frame.architecture returns the gdb.Architecture object
1724 corresponding to the frame's architecture.
1726 * New Python-based convenience functions:
1728 ** $_memeq(buf1, buf2, length)
1729 ** $_streq(str1, str2)
1731 ** $_regex(str, regex)
1733 * The 'cd' command now defaults to using '~' (the home directory) if not
1736 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1737 default for GCC since November 2000.
1739 * The command 'forward-search' can now be abbreviated as 'fo'.
1741 * The command 'info tracepoints' can now display 'installed on target'
1742 or 'not installed on target' for each non-pending location of tracepoint.
1744 * New configure options
1746 --enable-libmcheck/--disable-libmcheck
1747 By default, development versions are built with -lmcheck on hosts
1748 that support it, in order to help track memory corruption issues.
1749 Release versions, on the other hand, are built without -lmcheck
1750 by default. The --enable-libmcheck/--disable-libmcheck configure
1751 options allow the user to override that default.
1752 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1753 This configure option allows the user to build GDB with
1754 libbabeltrace using which GDB can read Common Trace Format data.
1756 * New commands (for set/show, see "New options" below)
1759 Catch signals. This is similar to "handle", but allows commands and
1760 conditions to be attached.
1763 List the BFDs known to GDB.
1765 python-interactive [command]
1767 Start a Python interactive prompt, or evaluate the optional command
1768 and print the result of expressions.
1771 "py" is a new alias for "python".
1773 enable type-printer [name]...
1774 disable type-printer [name]...
1775 Enable or disable type printers.
1779 ** For the Renesas Super-H architecture, the "regs" command has been removed
1780 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1785 set print type methods (on|off)
1786 show print type methods
1787 Control whether method declarations are displayed by "ptype".
1788 The default is to show them.
1790 set print type typedefs (on|off)
1791 show print type typedefs
1792 Control whether typedef definitions are displayed by "ptype".
1793 The default is to show them.
1795 set filename-display basename|relative|absolute
1796 show filename-display
1797 Control the way in which filenames is displayed.
1798 The default is "relative", which preserves previous behavior.
1800 set trace-buffer-size
1801 show trace-buffer-size
1802 Request target to change the size of trace buffer.
1804 set remote trace-buffer-size-packet auto|on|off
1805 show remote trace-buffer-size-packet
1806 Control the use of the remote protocol `QTBuffer:size' packet.
1810 Control display of debugging messages related to ARM AArch64.
1813 set debug coff-pe-read
1814 show debug coff-pe-read
1815 Control display of debugging messages related to reading of COFF/PE
1820 Control display of debugging messages related to Mach-O symbols
1823 set debug notification
1824 show debug notification
1825 Control display of debugging info for async remote notification.
1829 ** Command parameter changes are now notified using new async record
1830 "=cmd-param-changed".
1831 ** Trace frame changes caused by command "tfind" are now notified using
1832 new async record "=traceframe-changed".
1833 ** The creation, deletion and modification of trace state variables
1834 are now notified using new async records "=tsv-created",
1835 "=tsv-deleted" and "=tsv-modified".
1836 ** The start and stop of process record are now notified using new
1837 async record "=record-started" and "=record-stopped".
1838 ** Memory changes are now notified using new async record
1840 ** The data-disassemble command response will include a "fullname" field
1841 containing the absolute file name when source has been requested.
1842 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1843 command, to allow pattern filling of memory areas.
1844 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1845 library load/unload events.
1846 ** The response to breakpoint commands and breakpoint async records
1847 includes an "installed" field containing a boolean state about each
1848 non-pending tracepoint location is whether installed on target or not.
1849 ** Output of the "-trace-status" command includes a "trace-file" field
1850 containing the name of the trace file being examined. This field is
1851 optional, and only present when examining a trace file.
1852 ** The "fullname" field is now always present along with the "file" field,
1853 even if the file cannot be found by GDB.
1855 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1856 You must have the LZMA library available when configuring GDB for this
1857 feature to be enabled. For more information, see:
1858 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1860 * New remote packets
1863 Set the size of trace buffer. The remote stub reports support for this
1864 packet to gdb's qSupported query.
1867 Enable Branch Trace Store (BTS)-based branch tracing for the current
1868 thread. The remote stub reports support for this packet to gdb's
1872 Disable branch tracing for the current thread. The remote stub reports
1873 support for this packet to gdb's qSupported query.
1876 Read the traced branches for the current thread. The remote stub
1877 reports support for this packet to gdb's qSupported query.
1879 *** Changes in GDB 7.5
1881 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1882 for more x32 ABI info.
1884 * GDB now supports access to MIPS DSP registers on Linux targets.
1886 * GDB now supports debugging microMIPS binaries.
1888 * The "info os" command on GNU/Linux can now display information on
1889 several new classes of objects managed by the operating system:
1890 "info os procgroups" lists process groups
1891 "info os files" lists file descriptors
1892 "info os sockets" lists internet-domain sockets
1893 "info os shm" lists shared-memory regions
1894 "info os semaphores" lists semaphores
1895 "info os msg" lists message queues
1896 "info os modules" lists loaded kernel modules
1898 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1899 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1900 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1901 options and inspect the probe arguments using the new $_probe_arg family
1902 of convenience variables. You can obtain more information about SystemTap
1903 in <http://sourceware.org/systemtap/>.
1905 * GDB now supports reversible debugging on ARM, it allows you to
1906 debug basic ARM and THUMB instructions, and provides
1907 record/replay support.
1909 * The option "symbol-reloading" has been deleted as it is no longer used.
1913 ** GDB commands implemented in Python can now be put in command class
1916 ** The "maint set python print-stack on|off" is now deleted.
1918 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1919 apply "flag enum"-style pretty-printing to any enum.
1921 ** gdb.lookup_symbol can now work when there is no current frame.
1923 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1924 the source at which the symbol was defined.
1926 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1927 method 'value'. The former indicates whether the symbol needs a
1928 frame in order to compute its value, and the latter computes the
1931 ** A new method 'referenced_value' on gdb.Value objects which can
1932 dereference pointer as well as C++ reference values.
1934 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1935 which return the global and static blocks (as gdb.Block objects),
1936 of the underlying symbol table, respectively.
1938 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1939 object associated with a PC value.
1941 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1942 of the address range occupied by code for the current source line.
1944 * Go language support.
1945 GDB now supports debugging programs written in the Go programming
1948 * GDBserver now supports stdio connections.
1949 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1951 * The binary "gdbtui" can no longer be built or installed.
1952 Use "gdb -tui" instead.
1954 * GDB will now print "flag" enums specially. A flag enum is one where
1955 all the enumerator values have no bits in common when pairwise
1956 "and"ed. When printing a value whose type is a flag enum, GDB will
1957 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1958 (gdb) print (enum E) 3
1961 * The filename part of a linespec will now match trailing components
1962 of a source file name. For example, "break gcc/expr.c:1000" will
1963 now set a breakpoint in build/gcc/expr.c, but not
1964 build/libcpp/expr.c.
1966 * The "info proc" and "generate-core-file" commands will now also
1967 work on remote targets connected to GDBserver on Linux.
1969 * The command "info catch" has been removed. It has been disabled
1970 since December 2007.
1972 * The "catch exception" and "catch assert" commands now accept
1973 a condition at the end of the command, much like the "break"
1974 command does. For instance:
1976 (gdb) catch exception Constraint_Error if Barrier = True
1978 Previously, it was possible to add a condition to such catchpoints,
1979 but it had to be done as a second step, after the catchpoint had been
1980 created, using the "condition" command.
1982 * The "info static-tracepoint-marker" command will now also work on
1983 native Linux targets with in-process agent.
1985 * GDB can now set breakpoints on inlined functions.
1987 * The .gdb_index section has been updated to include symbols for
1988 inlined functions. GDB will ignore older .gdb_index sections by
1989 default, which could cause symbol files to be loaded more slowly
1990 until their .gdb_index sections can be recreated. The new command
1991 "set use-deprecated-index-sections on" will cause GDB to use any older
1992 .gdb_index sections it finds. This will restore performance, but the
1993 ability to set breakpoints on inlined functions will be lost in symbol
1994 files with older .gdb_index sections.
1996 The .gdb_index section has also been updated to record more information
1997 about each symbol. This speeds up the "info variables", "info functions"
1998 and "info types" commands when used with programs having the .gdb_index
1999 section, as well as speeding up debugging with shared libraries using
2000 the .gdb_index section.
2002 * Ada support for GDB/MI Variable Objects has been added.
2004 * GDB can now support 'breakpoint always-inserted mode' in 'record'
2009 ** New command -info-os is the MI equivalent of "info os".
2011 ** Output logs ("set logging" and related) now include MI output.
2015 ** "set use-deprecated-index-sections on|off"
2016 "show use-deprecated-index-sections on|off"
2017 Controls the use of deprecated .gdb_index sections.
2019 ** "catch load" and "catch unload" can be used to stop when a shared
2020 library is loaded or unloaded, respectively.
2022 ** "enable count" can be used to auto-disable a breakpoint after
2025 ** "info vtbl" can be used to show the virtual method tables for
2026 C++ and Java objects.
2028 ** "explore" and its sub commands "explore value" and "explore type"
2029 can be used to recursively explore values and types of
2030 expressions. These commands are available only if GDB is
2031 configured with '--with-python'.
2033 ** "info auto-load" shows status of all kinds of auto-loaded files,
2034 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
2035 sequences of commands files, "info auto-load python-scripts"
2036 shows status of auto-loading Python script files,
2037 "info auto-load local-gdbinit" shows status of loading init file
2038 (.gdbinit) from current directory and "info auto-load libthread-db" shows
2039 status of inferior specific thread debugging shared library loading.
2041 ** "info auto-load-scripts", "set auto-load-scripts on|off"
2042 and "show auto-load-scripts" commands have been deprecated, use their
2043 "info auto-load python-scripts", "set auto-load python-scripts on|off"
2044 and "show auto-load python-scripts" counterparts instead.
2046 ** "dprintf location,format,args..." creates a dynamic printf, which
2047 is basically a breakpoint that does a printf and immediately
2048 resumes your program's execution, so it is like a printf that you
2049 can insert dynamically at runtime instead of at compiletime.
2051 ** "set print symbol"
2053 Controls whether GDB attempts to display the symbol, if any,
2054 corresponding to addresses it prints. This defaults to "on", but
2055 you can set it to "off" to restore GDB's previous behavior.
2057 * Deprecated commands
2059 ** For the Renesas Super-H architecture, the "regs" command has been
2060 deprecated, and "info all-registers" should be used instead.
2064 Renesas RL78 rl78-*-elf
2065 HP OpenVMS ia64 ia64-hp-openvms*
2067 * GDBserver supports evaluation of breakpoint conditions. When
2068 support is advertised by GDBserver, GDB may be told to send the
2069 breakpoint conditions in bytecode form to GDBserver. GDBserver
2070 will only report the breakpoint trigger to GDB when its condition
2075 set mips compression
2076 show mips compression
2077 Select the compressed ISA encoding used in functions that have no symbol
2078 information available. The encoding can be set to either of:
2081 and is updated automatically from ELF file flags if available.
2083 set breakpoint condition-evaluation
2084 show breakpoint condition-evaluation
2085 Control whether breakpoint conditions are evaluated by GDB ("host") or by
2086 GDBserver ("target"). Default option "auto" chooses the most efficient
2088 This option can improve debugger efficiency depending on the speed of the
2092 Disable auto-loading globally.
2095 Show auto-loading setting of all kinds of auto-loaded files.
2097 set auto-load gdb-scripts on|off
2098 show auto-load gdb-scripts
2099 Control auto-loading of GDB canned sequences of commands files.
2101 set auto-load python-scripts on|off
2102 show auto-load python-scripts
2103 Control auto-loading of Python script files.
2105 set auto-load local-gdbinit on|off
2106 show auto-load local-gdbinit
2107 Control loading of init file (.gdbinit) from current directory.
2109 set auto-load libthread-db on|off
2110 show auto-load libthread-db
2111 Control auto-loading of inferior specific thread debugging shared library.
2113 set auto-load scripts-directory <dir1>[:<dir2>...]
2114 show auto-load scripts-directory
2115 Set a list of directories from which to load auto-loaded scripts.
2116 Automatically loaded Python scripts and GDB scripts are located in one
2117 of the directories listed by this option.
2118 The delimiter (':' above) may differ according to the host platform.
2120 set auto-load safe-path <dir1>[:<dir2>...]
2121 show auto-load safe-path
2122 Set a list of directories from which it is safe to auto-load files.
2123 The delimiter (':' above) may differ according to the host platform.
2125 set debug auto-load on|off
2126 show debug auto-load
2127 Control display of debugging info for auto-loading the files above.
2129 set dprintf-style gdb|call|agent
2131 Control the way in which a dynamic printf is performed; "gdb"
2132 requests a GDB printf command, while "call" causes dprintf to call a
2133 function in the inferior. "agent" requests that the target agent
2134 (such as GDBserver) do the printing.
2136 set dprintf-function <expr>
2137 show dprintf-function
2138 set dprintf-channel <expr>
2139 show dprintf-channel
2140 Set the function and optional first argument to the call when using
2141 the "call" style of dynamic printf.
2143 set disconnected-dprintf on|off
2144 show disconnected-dprintf
2145 Control whether agent-style dynamic printfs continue to be in effect
2146 after GDB disconnects.
2148 * New configure options
2150 --with-auto-load-dir
2151 Configure default value for the 'set auto-load scripts-directory'
2152 setting above. It defaults to '$debugdir:$datadir/auto-load',
2153 $debugdir representing global debugging info directories (available
2154 via 'show debug-file-directory') and $datadir representing GDB's data
2155 directory (available via 'show data-directory').
2157 --with-auto-load-safe-path
2158 Configure default value for the 'set auto-load safe-path' setting
2159 above. It defaults to the --with-auto-load-dir setting.
2161 --without-auto-load-safe-path
2162 Set 'set auto-load safe-path' to '/', effectively disabling this
2165 * New remote packets
2167 z0/z1 conditional breakpoints extension
2169 The z0/z1 breakpoint insertion packets have been extended to carry
2170 a list of conditional expressions over to the remote stub depending on the
2171 condition evaluation mode. The use of this extension can be controlled
2172 via the "set remote conditional-breakpoints-packet" command.
2176 Specify the signals which the remote stub may pass to the debugged
2177 program without GDB involvement.
2179 * New command line options
2181 --init-command=FILE, -ix Like --command, -x but execute it
2182 before loading inferior.
2183 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
2184 execute it before loading inferior.
2186 *** Changes in GDB 7.4
2188 * GDB now handles ambiguous linespecs more consistently; the existing
2189 FILE:LINE support has been expanded to other types of linespecs. A
2190 breakpoint will now be set on all matching locations in all
2191 inferiors, and locations will be added or removed according to
2194 * GDB now allows you to skip uninteresting functions and files when
2195 stepping with the "skip function" and "skip file" commands.
2197 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
2198 and "show remote hardware-watchpoint-length-limit". These allows to
2199 set or show the maximum length limit (in bytes) of a remote
2200 target hardware watchpoint.
2202 This allows e.g. to use "unlimited" hardware watchpoints with the
2203 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
2204 watchpoints are slower than real hardware watchpoints but are
2205 significantly faster than gdb software watchpoints.
2209 ** The register_pretty_printer function in module gdb.printing now takes
2210 an optional `replace' argument. If True, the new printer replaces any
2213 ** The "maint set python print-stack on|off" command has been
2214 deprecated and will be deleted in GDB 7.5.
2215 A new command: "set python print-stack none|full|message" has
2216 replaced it. Additionally, the default for "print-stack" is
2217 now "message", which just prints the error message without
2220 ** A prompt substitution hook (prompt_hook) is now available to the
2223 ** A new Python module, gdb.prompt has been added to the GDB Python
2224 modules library. This module provides functionality for
2225 escape sequences in prompts (used by set/show
2226 extended-prompt). These escape sequences are replaced by their
2227 corresponding value.
2229 ** Python commands and convenience-functions located in
2230 'data-directory'/python/gdb/command and
2231 'data-directory'/python/gdb/function are now automatically loaded
2234 ** Blocks now provide four new attributes. global_block and
2235 static_block will return the global and static blocks
2236 respectively. is_static and is_global are boolean attributes
2237 that indicate if the block is one of those two types.
2239 ** Symbols now provide the "type" attribute, the type of the symbol.
2241 ** The "gdb.breakpoint" function has been deprecated in favor of
2244 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2245 of a function. This class is based on the "finish" command
2246 available in the CLI.
2248 ** Type objects for struct and union types now allow access to
2249 the fields using standard Python dictionary (mapping) methods.
2250 For example, "some_type['myfield']" now works, as does
2251 "some_type.items()".
2253 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2256 ** A new function, "deep_items" has been added to the gdb.types
2257 module in the GDB Python modules library. This function returns
2258 an iterator over the fields of a struct or union type. Unlike
2259 the standard Python "iteritems" method, it will recursively traverse
2260 any anonymous fields.
2264 ** "*stopped" events can report several new "reason"s, such as
2267 ** Breakpoint changes are now notified using new async records, like
2268 "=breakpoint-modified".
2270 ** New command -ada-task-info.
2272 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2273 $sdir specifies the default system locations of shared libraries.
2274 $pdir specifies the directory where the libpthread used by the application
2277 GDB no longer looks in $sdir and $pdir after it has searched the directories
2278 mentioned in libthread-db-search-path. If you want to search those
2279 directories, they must be specified in libthread-db-search-path.
2280 The default value of libthread-db-search-path on GNU/Linux and Solaris
2281 systems is now "$sdir:$pdir".
2283 $pdir is not supported by gdbserver, it is currently ignored.
2284 $sdir is supported by gdbserver.
2286 * New configure option --with-iconv-bin.
2287 When using the internationalization support like the one in the GNU C
2288 library, GDB will invoke the "iconv" program to get a list of supported
2289 character sets. If this program lives in a non-standard location, one can
2290 use this option to specify where to find it.
2292 * When natively debugging programs on PowerPC BookE processors running
2293 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2294 watchpoints, which specify a mask in addition to an address to watch.
2295 The mask specifies that some bits of an address (the bits which are
2296 reset in the mask) should be ignored when matching the address accessed
2297 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2298 section in the user manual for more details.
2300 * The new option --once causes GDBserver to stop listening for connections once
2301 the first connection is made. The listening port used by GDBserver will
2302 become available after that.
2304 * New commands "info macros" and "alias" have been added.
2306 * New function parameters suffix @entry specifies value of function parameter
2307 at the time the function got called. Entry values are available only since
2313 "!" is now an alias of the "shell" command.
2314 Note that no space is needed between "!" and SHELL COMMAND.
2318 watch EXPRESSION mask MASK_VALUE
2319 The watch command now supports the mask argument which allows creation
2320 of masked watchpoints, if the current architecture supports this feature.
2322 info auto-load-scripts [REGEXP]
2323 This command was formerly named "maintenance print section-scripts".
2324 It is now generally useful and is no longer a maintenance-only command.
2326 info macro [-all] [--] MACRO
2327 The info macro command has new options `-all' and `--'. The first for
2328 printing all definitions of a macro. The second for explicitly specifying
2329 the end of arguments and the beginning of the macro name in case the macro
2330 name starts with a hyphen.
2332 collect[/s] EXPRESSIONS
2333 The tracepoint collect command now takes an optional modifier "/s"
2334 that directs it to dereference pointer-to-character types and
2335 collect the bytes of memory up to a zero byte. The behavior is
2336 similar to what you see when you use the regular print command on a
2337 string. An optional integer following the "/s" sets a bound on the
2338 number of bytes that will be collected.
2341 The trace start command now interprets any supplied arguments as a
2342 note to be recorded with the trace run, with an effect similar to
2343 setting the variable trace-notes.
2346 The trace stop command now interprets any arguments as a note to be
2347 mentioned along with the tstatus report that the trace was stopped
2348 with a command. The effect is similar to setting the variable
2351 * Tracepoints can now be enabled and disabled at any time after a trace
2352 experiment has been started using the standard "enable" and "disable"
2353 commands. It is now possible to start a trace experiment with no enabled
2354 tracepoints; GDB will display a warning, but will allow the experiment to
2355 begin, assuming that tracepoints will be enabled as needed while the trace
2358 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2359 locations with 4-byte instructions, when they were previously
2360 limited to locations with instructions of 5 bytes or longer.
2364 set debug dwarf2-read
2365 show debug dwarf2-read
2366 Turns on or off display of debugging messages related to reading
2367 DWARF debug info. The default is off.
2369 set debug symtab-create
2370 show debug symtab-create
2371 Turns on or off display of debugging messages related to symbol table
2372 creation. The default is off.
2375 show extended-prompt
2376 Set the GDB prompt, and allow escape sequences to be inserted to
2377 display miscellaneous information (see 'help set extended-prompt'
2378 for the list of sequences). This prompt (and any information
2379 accessed through the escape sequences) is updated every time the
2380 prompt is displayed.
2382 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2383 show print entry-values
2384 Set printing of frame argument values at function entry. In some cases
2385 GDB can determine the value of function argument which was passed by the
2386 function caller, even if the value was modified inside the called function.
2388 set debug entry-values
2389 show debug entry-values
2390 Control display of debugging info for determining frame argument values at
2391 function entry and virtual tail call frames.
2393 set basenames-may-differ
2394 show basenames-may-differ
2395 Set whether a source file may have multiple base names.
2396 (A "base name" is the name of a file with the directory part removed.
2397 Example: The base name of "/home/user/hello.c" is "hello.c".)
2398 If set, GDB will canonicalize file names (e.g., expand symlinks)
2399 before comparing them. Canonicalization is an expensive operation,
2400 but it allows the same file be known by more than one base name.
2401 If not set (the default), all source files are assumed to have just
2402 one base name, and gdb will do file name comparisons more efficiently.
2408 Set a user name and notes for the current and any future trace runs.
2409 This is useful for long-running and/or disconnected traces, to
2410 inform others (or yourself) as to who is running the trace, supply
2411 contact information, or otherwise explain what is going on.
2413 set trace-stop-notes
2414 show trace-stop-notes
2415 Set a note attached to the trace run, that is displayed when the
2416 trace has been stopped by a tstop command. This is useful for
2417 instance as an explanation, if you are stopping a trace run that was
2418 started by someone else.
2420 * New remote packets
2424 Dynamically enable a tracepoint in a started trace experiment.
2428 Dynamically disable a tracepoint in a started trace experiment.
2432 Set the user and notes of the trace run.
2436 Query the current status of a tracepoint.
2440 Query the minimum length of instruction at which a fast tracepoint may
2443 * Dcache size (number of lines) and line-size are now runtime-configurable
2444 via "set dcache line" and "set dcache line-size" commands.
2448 Texas Instruments TMS320C6x tic6x-*-*
2452 Renesas RL78 rl78-*-elf
2454 *** Changes in GDB 7.3.1
2456 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2458 *** Changes in GDB 7.3
2460 * GDB has a new command: "thread find [REGEXP]".
2461 It finds the thread id whose name, target id, or thread extra info
2462 matches the given regular expression.
2464 * The "catch syscall" command now works on mips*-linux* targets.
2466 * The -data-disassemble MI command now supports modes 2 and 3 for
2467 dumping the instruction opcodes.
2469 * New command line options
2471 -data-directory DIR Specify DIR as the "data-directory".
2472 This is mostly for testing purposes.
2474 * The "maint set python auto-load on|off" command has been renamed to
2475 "set auto-load-scripts on|off".
2477 * GDB has a new command: "set directories".
2478 It is like the "dir" command except that it replaces the
2479 source path list instead of augmenting it.
2481 * GDB now understands thread names.
2483 On GNU/Linux, "info threads" will display the thread name as set by
2484 prctl or pthread_setname_np.
2486 There is also a new command, "thread name", which can be used to
2487 assign a name internally for GDB to display.
2490 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2491 has been integrated into GDB.
2495 ** The function gdb.Write now accepts an optional keyword 'stream'.
2496 This keyword, when provided, will direct the output to either
2497 stdout, stderr, or GDB's logging output.
2499 ** Parameters can now be be sub-classed in Python, and in particular
2500 you may implement the get_set_doc and get_show_doc functions.
2501 This improves how Parameter set/show documentation is processed
2502 and allows for more dynamic content.
2504 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2505 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2506 have an is_valid method.
2508 ** Breakpoints can now be sub-classed in Python, and in particular
2509 you may implement a 'stop' function that is executed each time
2510 the inferior reaches that breakpoint.
2512 ** New function gdb.lookup_global_symbol looks up a global symbol.
2514 ** GDB values in Python are now callable if the value represents a
2515 function. For example, if 'some_value' represents a function that
2516 takes two integer parameters and returns a value, you can call
2517 that function like so:
2519 result = some_value (10,20)
2521 ** Module gdb.types has been added.
2522 It contains a collection of utilities for working with gdb.Types objects:
2523 get_basic_type, has_field, make_enum_dict.
2525 ** Module gdb.printing has been added.
2526 It contains utilities for writing and registering pretty-printers.
2527 New classes: PrettyPrinter, SubPrettyPrinter,
2528 RegexpCollectionPrettyPrinter.
2529 New function: register_pretty_printer.
2531 ** New commands "info pretty-printers", "enable pretty-printer" and
2532 "disable pretty-printer" have been added.
2534 ** gdb.parameter("directories") is now available.
2536 ** New function gdb.newest_frame returns the newest frame in the
2539 ** The gdb.InferiorThread class has a new "name" attribute. This
2540 holds the thread's name.
2542 ** Python Support for Inferior events.
2543 Python scripts can add observers to be notified of events
2544 occurring in the process being debugged.
2545 The following events are currently supported:
2546 - gdb.events.cont Continue event.
2547 - gdb.events.exited Inferior exited event.
2548 - gdb.events.stop Signal received, and Breakpoint hit events.
2552 ** GDB now puts template parameters in scope when debugging in an
2553 instantiation. For example, if you have:
2555 template<int X> int func (void) { return X; }
2557 then if you step into func<5>, "print X" will show "5". This
2558 feature requires proper debuginfo support from the compiler; it
2559 was added to GCC 4.5.
2561 ** The motion commands "next", "finish", "until", and "advance" now
2562 work better when exceptions are thrown. In particular, GDB will
2563 no longer lose control of the inferior; instead, the GDB will
2564 stop the inferior at the point at which the exception is caught.
2565 This functionality requires a change in the exception handling
2566 code that was introduced in GCC 4.5.
2568 * GDB now follows GCC's rules on accessing volatile objects when
2569 reading or writing target state during expression evaluation.
2570 One notable difference to prior behavior is that "print x = 0"
2571 no longer generates a read of x; the value of the assignment is
2572 now always taken directly from the value being assigned.
2574 * GDB now has some support for using labels in the program's source in
2575 linespecs. For instance, you can use "advance label" to continue
2576 execution to a label.
2578 * GDB now has support for reading and writing a new .gdb_index
2579 section. This section holds a fast index of DWARF debugging
2580 information and can be used to greatly speed up GDB startup and
2581 operation. See the documentation for `save gdb-index' for details.
2583 * The "watch" command now accepts an optional "-location" argument.
2584 When used, this causes GDB to watch the memory referred to by the
2585 expression. Such a watchpoint is never deleted due to it going out
2588 * GDB now supports thread debugging of core dumps on GNU/Linux.
2590 GDB now activates thread debugging using the libthread_db library
2591 when debugging GNU/Linux core dumps, similarly to when debugging
2592 live processes. As a result, when debugging a core dump file, GDB
2593 is now able to display pthread_t ids of threads. For example, "info
2594 threads" shows the same output as when debugging the process when it
2595 was live. In earlier releases, you'd see something like this:
2598 * 1 LWP 6780 main () at main.c:10
2600 While now you see this:
2603 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2605 It is also now possible to inspect TLS variables when debugging core
2608 When debugging a core dump generated on a machine other than the one
2609 used to run GDB, you may need to point GDB at the correct
2610 libthread_db library with the "set libthread-db-search-path"
2611 command. See the user manual for more details on this command.
2613 * When natively debugging programs on PowerPC BookE processors running
2614 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2615 which stop execution of the inferior whenever it executes an instruction
2616 at any address within the specified range. See the "PowerPC Embedded"
2617 section in the user manual for more details.
2619 * New features in the GDB remote stub, GDBserver
2621 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2622 and i686 LynxOS (version 5.x).
2624 ** GDBserver is now supported on Blackfin Linux.
2626 * New native configurations
2628 ia64 HP-UX ia64-*-hpux*
2632 Analog Devices, Inc. Blackfin Processor bfin-*
2634 * Ada task switching is now supported on sparc-elf targets when
2635 debugging a program using the Ravenscar Profile. For more information,
2636 see the "Tasking Support when using the Ravenscar Profile" section
2637 in the GDB user manual.
2639 * Guile support was removed.
2641 * New features in the GNU simulator
2643 ** The --map-info flag lists all known core mappings.
2645 ** CFI flashes may be simulated via the "cfi" device.
2647 *** Changes in GDB 7.2
2649 * Shared library support for remote targets by default
2651 When GDB is configured for a generic, non-OS specific target, like
2652 for example, --target=arm-eabi or one of the many *-*-elf targets,
2653 GDB now queries remote stubs for loaded shared libraries using the
2654 `qXfer:libraries:read' packet. Previously, shared library support
2655 was always disabled for such configurations.
2659 ** Argument Dependent Lookup (ADL)
2661 In C++ ADL lookup directs function search to the namespaces of its
2662 arguments even if the namespace has not been imported.
2672 Here the compiler will search for `foo' in the namespace of 'b'
2673 and find A::foo. GDB now supports this. This construct is commonly
2674 used in the Standard Template Library for operators.
2676 ** Improved User Defined Operator Support
2678 In addition to member operators, GDB now supports lookup of operators
2679 defined in a namespace and imported with a `using' directive, operators
2680 defined in the global scope, operators imported implicitly from an
2681 anonymous namespace, and the ADL operators mentioned in the previous
2683 GDB now also supports proper overload resolution for all the previously
2684 mentioned flavors of operators.
2686 ** static const class members
2688 Printing of static const class members that are initialized in the
2689 class definition has been fixed.
2691 * Windows Thread Information Block access.
2693 On Windows targets, GDB now supports displaying the Windows Thread
2694 Information Block (TIB) structure. This structure is visible either
2695 by using the new command `info w32 thread-information-block' or, by
2696 dereferencing the new convenience variable named `$_tlb', a
2697 thread-specific pointer to the TIB. This feature is also supported
2698 when remote debugging using GDBserver.
2700 * Static tracepoints
2702 Static tracepoints are calls in the user program into a tracing
2703 library. One such library is a port of the LTTng kernel tracer to
2704 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2705 When debugging with GDBserver, GDB now supports combining the GDB
2706 tracepoint machinery with such libraries. For example: the user can
2707 use GDB to probe a static tracepoint marker (a call from the user
2708 program into the tracing library) with the new "strace" command (see
2709 "New commands" below). This creates a "static tracepoint" in the
2710 breakpoint list, that can be manipulated with the same feature set
2711 as fast and regular tracepoints. E.g., collect registers, local and
2712 global variables, collect trace state variables, and define
2713 tracepoint conditions. In addition, the user can collect extra
2714 static tracepoint marker specific data, by collecting the new
2715 $_sdata internal variable. When analyzing the trace buffer, you can
2716 inspect $_sdata like any other variable available to GDB. For more
2717 information, see the "Tracepoints" chapter in GDB user manual. New
2718 remote packets have been defined to support static tracepoints, see
2719 the "New remote packets" section below.
2721 * Better reconstruction of tracepoints after disconnected tracing
2723 GDB will attempt to download the original source form of tracepoint
2724 definitions when starting a trace run, and then will upload these
2725 upon reconnection to the target, resulting in a more accurate
2726 reconstruction of the tracepoints that are in use on the target.
2730 You can now exercise direct control over the ways that GDB can
2731 affect your program. For instance, you can disallow the setting of
2732 breakpoints, so that the program can run continuously (assuming
2733 non-stop mode). In addition, the "observer" variable is available
2734 to switch all of the different controls; in observer mode, GDB
2735 cannot affect the target's behavior at all, which is useful for
2736 tasks like diagnosing live systems in the field.
2738 * The new convenience variable $_thread holds the number of the
2741 * New remote packets
2745 Return the address of the Windows Thread Information Block of a given thread.
2749 In response to several of the tracepoint packets, the target may now
2750 also respond with a number of intermediate `qRelocInsn' request
2751 packets before the final result packet, to have GDB handle
2752 relocating an instruction to execute at a different address. This
2753 is particularly useful for stubs that support fast tracepoints. GDB
2754 reports support for this feature in the qSupported packet.
2758 List static tracepoint markers in the target program.
2762 List static tracepoint markers at a given address in the target
2765 qXfer:statictrace:read
2767 Read the static trace data collected (by a `collect $_sdata'
2768 tracepoint action). The remote stub reports support for this packet
2769 to gdb's qSupported query.
2773 Send the current settings of GDB's permission flags.
2777 Send part of the source (textual) form of a tracepoint definition,
2778 which includes location, conditional, and action list.
2780 * The source command now accepts a -s option to force searching for the
2781 script in the source search path even if the script name specifies
2784 * New features in the GDB remote stub, GDBserver
2786 - GDBserver now support tracepoints (including fast tracepoints, and
2787 static tracepoints). The feature is currently supported by the
2788 i386-linux and amd64-linux builds. See the "Tracepoints support
2789 in gdbserver" section in the manual for more information.
2791 GDBserver JIT compiles the tracepoint's conditional agent
2792 expression bytecode into native code whenever possible for low
2793 overhead dynamic tracepoints conditionals. For such tracepoints,
2794 an expression that examines program state is evaluated when the
2795 tracepoint is reached, in order to determine whether to capture
2796 trace data. If the condition is simple and false, processing the
2797 tracepoint finishes very quickly and no data is gathered.
2799 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2800 for static tracepoints support.
2802 - GDBserver now supports x86_64 Windows 64-bit debugging.
2804 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2805 it understands register description.
2807 * The --batch flag now disables pagination and queries.
2809 * X86 general purpose registers
2811 GDB now supports reading/writing byte, word and double-word x86
2812 general purpose registers directly. This means you can use, say,
2813 $ah or $ax to refer, respectively, to the byte register AH and
2814 16-bit word register AX that are actually portions of the 32-bit
2815 register EAX or 64-bit register RAX.
2817 * The `commands' command now accepts a range of breakpoints to modify.
2818 A plain `commands' following a command that creates multiple
2819 breakpoints affects all the breakpoints set by that command. This
2820 applies to breakpoints set by `rbreak', and also applies when a
2821 single `break' command creates multiple breakpoints (e.g.,
2822 breakpoints on overloaded c++ functions).
2824 * The `rbreak' command now accepts a filename specification as part of
2825 its argument, limiting the functions selected by the regex to those
2826 in the specified file.
2828 * Support for remote debugging Windows and SymbianOS shared libraries
2829 from Unix hosts has been improved. Non Windows GDB builds now can
2830 understand target reported file names that follow MS-DOS based file
2831 system semantics, such as file names that include drive letters and
2832 use the backslash character as directory separator. This makes it
2833 possible to transparently use the "set sysroot" and "set
2834 solib-search-path" on Unix hosts to point as host copies of the
2835 target's shared libraries. See the new command "set
2836 target-file-system-kind" described below, and the "Commands to
2837 specify files" section in the user manual for more information.
2841 eval template, expressions...
2842 Convert the values of one or more expressions under the control
2843 of the string template to a command line, and call it.
2845 set target-file-system-kind unix|dos-based|auto
2846 show target-file-system-kind
2847 Set or show the assumed file system kind for target reported file
2850 save breakpoints <filename>
2851 Save all current breakpoint definitions to a file suitable for use
2852 in a later debugging session. To read the saved breakpoint
2853 definitions, use the `source' command.
2855 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2858 info static-tracepoint-markers
2859 Display information about static tracepoint markers in the target.
2861 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2862 Define a static tracepoint by probing a marker at the given
2863 function, line, address, or marker ID.
2867 Enable and disable observer mode.
2869 set may-write-registers on|off
2870 set may-write-memory on|off
2871 set may-insert-breakpoints on|off
2872 set may-insert-tracepoints on|off
2873 set may-insert-fast-tracepoints on|off
2874 set may-interrupt on|off
2875 Set individual permissions for GDB effects on the target. Note that
2876 some of these settings can have undesirable or surprising
2877 consequences, particularly when changed in the middle of a session.
2878 For instance, disabling the writing of memory can prevent
2879 breakpoints from being inserted, cause single-stepping to fail, or
2880 even crash your program, if you disable after breakpoints have been
2881 inserted. However, GDB should not crash.
2883 set record memory-query on|off
2884 show record memory-query
2885 Control whether to stop the inferior if memory changes caused
2886 by an instruction cannot be recorded.
2891 The disassemble command now supports "start,+length" form of two arguments.
2895 ** GDB now provides a new directory location, called the python directory,
2896 where Python scripts written for GDB can be installed. The location
2897 of that directory is <data-directory>/python, where <data-directory>
2898 is the GDB data directory. For more details, see section `Scripting
2899 GDB using Python' in the manual.
2901 ** The GDB Python API now has access to breakpoints, symbols, symbol
2902 tables, program spaces, inferiors, threads and frame's code blocks.
2903 Additionally, GDB Parameters can now be created from the API, and
2904 manipulated via set/show in the CLI.
2906 ** New functions gdb.target_charset, gdb.target_wide_charset,
2907 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2909 ** New exception gdb.GdbError.
2911 ** Pretty-printers are now also looked up in the current program space.
2913 ** Pretty-printers can now be individually enabled and disabled.
2915 ** GDB now looks for names of Python scripts to auto-load in a
2916 special section named `.debug_gdb_scripts', in addition to looking
2917 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2919 * Tracepoint actions were unified with breakpoint commands. In particular,
2920 there are no longer differences in "info break" output for breakpoints and
2921 tracepoints and the "commands" command can be used for both tracepoints and
2922 regular breakpoints.
2926 ARM Symbian arm*-*-symbianelf*
2928 * D language support.
2929 GDB now supports debugging programs written in the D programming
2932 * GDB now supports the extended ptrace interface for PowerPC which is
2933 available since Linux kernel version 2.6.34. This automatically enables
2934 any hardware breakpoints and additional hardware watchpoints available in
2935 the processor. The old ptrace interface exposes just one hardware
2936 watchpoint and no hardware breakpoints.
2938 * GDB is now able to use the Data Value Compare (DVC) register available on
2939 embedded PowerPC processors to implement in hardware simple watchpoint
2940 conditions of the form:
2942 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2944 This works in native GDB running on Linux kernels with the extended ptrace
2945 interface mentioned above.
2947 *** Changes in GDB 7.1
2951 ** Namespace Support
2953 GDB now supports importing of namespaces in C++. This enables the
2954 user to inspect variables from imported namespaces. Support for
2955 namepace aliasing has also been added. So, if a namespace is
2956 aliased in the current scope (e.g. namepace C=A; ) the user can
2957 print variables using the alias (e.g. (gdb) print C::x).
2961 All known bugs relating to the printing of virtual base class were
2962 fixed. It is now possible to call overloaded static methods using a
2967 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2968 and reinterpret_cast<> are now handled by the C++ expression parser.
2972 Xilinx MicroBlaze microblaze-*-*
2977 Xilinx MicroBlaze microblaze
2980 * Multi-program debugging.
2982 GDB now has support for multi-program (a.k.a. multi-executable or
2983 multi-exec) debugging. This allows for debugging multiple inferiors
2984 simultaneously each running a different program under the same GDB
2985 session. See "Debugging Multiple Inferiors and Programs" in the
2986 manual for more information. This implied some user visible changes
2987 in the multi-inferior support. For example, "info inferiors" now
2988 lists inferiors that are not running yet or that have exited
2989 already. See also "New commands" and "New options" below.
2991 * New tracing features
2993 GDB's tracepoint facility now includes several new features:
2995 ** Trace state variables
2997 GDB tracepoints now include support for trace state variables, which
2998 are variables managed by the target agent during a tracing
2999 experiment. They are useful for tracepoints that trigger each
3000 other, so for instance one tracepoint can count hits in a variable,
3001 and then a second tracepoint has a condition that is true when the
3002 count reaches a particular value. Trace state variables share the
3003 $-syntax of GDB convenience variables, and can appear in both
3004 tracepoint actions and condition expressions. Use the "tvariable"
3005 command to create, and "info tvariables" to view; see "Trace State
3006 Variables" in the manual for more detail.
3010 GDB now includes an option for defining fast tracepoints, which
3011 targets may implement more efficiently, such as by installing a jump
3012 into the target agent rather than a trap instruction. The resulting
3013 speedup can be by two orders of magnitude or more, although the
3014 tradeoff is that some program locations on some target architectures
3015 might not allow fast tracepoint installation, for instance if the
3016 instruction to be replaced is shorter than the jump. To request a
3017 fast tracepoint, use the "ftrace" command, with syntax identical to
3018 the regular trace command.
3020 ** Disconnected tracing
3022 It is now possible to detach GDB from the target while it is running
3023 a trace experiment, then reconnect later to see how the experiment
3024 is going. In addition, a new variable disconnected-tracing lets you
3025 tell the target agent whether to continue running a trace if the
3026 connection is lost unexpectedly.
3030 GDB now has the ability to save the trace buffer into a file, and
3031 then use that file as a target, similarly to you can do with
3032 corefiles. You can select trace frames, print data that was
3033 collected in them, and use tstatus to display the state of the
3034 tracing run at the moment that it was saved. To create a trace
3035 file, use "tsave <filename>", and to use it, do "target tfile
3038 ** Circular trace buffer
3040 You can ask the target agent to handle the trace buffer as a
3041 circular buffer, discarding the oldest trace frames to make room for
3042 newer ones, by setting circular-trace-buffer to on. This feature may
3043 not be available for all target agents.
3048 The disassemble command, when invoked with two arguments, now requires
3049 the arguments to be comma-separated.
3052 The info variables command now displays variable definitions. Files
3053 which only declare a variable are not shown.
3056 The source command is now capable of sourcing Python scripts.
3057 This feature is dependent on the debugger being build with Python
3060 Related to this enhancement is also the introduction of a new command
3061 "set script-extension" (see below).
3063 * New commands (for set/show, see "New options" below)
3065 record save [<FILENAME>]
3066 Save a file (in core file format) containing the process record
3067 execution log for replay debugging at a later time.
3069 record restore <FILENAME>
3070 Restore the process record execution log that was saved at an
3071 earlier time, for replay debugging.
3073 add-inferior [-copies <N>] [-exec <FILENAME>]
3076 clone-inferior [-copies <N>] [ID]
3077 Make a new inferior ready to execute the same program another
3078 inferior has loaded.
3083 maint info program-spaces
3084 List the program spaces loaded into GDB.
3086 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
3087 show remote interrupt-sequence
3088 Allow the user to select one of ^C, a BREAK signal or BREAK-g
3089 as the sequence to the remote target in order to interrupt the execution.
3090 Ctrl-C is a default. Some system prefers BREAK which is high level of
3091 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
3092 Magic SysRq g. It is BREAK signal and character 'g'.
3094 set remote interrupt-on-connect [on | off]
3095 show remote interrupt-on-connect
3096 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
3097 remote target when gdb connects to it. This is needed when you debug
3100 set remotebreak [on | off]
3102 Deprecated. Use "set/show remote interrupt-sequence" instead.
3104 tvariable $NAME [ = EXP ]
3105 Create or modify a trace state variable.
3108 List trace state variables and their values.
3110 delete tvariable $NAME ...
3111 Delete one or more trace state variables.
3114 Evaluate the given expressions without collecting anything into the
3115 trace buffer. (Valid in tracepoint actions only.)
3117 ftrace FN / FILE:LINE / *ADDR
3118 Define a fast tracepoint at the given function, line, or address.
3120 * New expression syntax
3122 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
3123 GDB now parses 0b101010 identically with 42.
3127 set follow-exec-mode new|same
3128 show follow-exec-mode
3129 Control whether GDB reuses the same inferior across an exec call or
3130 creates a new one. This is useful to be able to restart the old
3131 executable after the inferior having done an exec call.
3133 set default-collect EXPR, ...
3134 show default-collect
3135 Define a list of expressions to be collected at each tracepoint.
3136 This is a useful way to ensure essential items are not overlooked,
3137 such as registers or a critical global variable.
3139 set disconnected-tracing
3140 show disconnected-tracing
3141 If set to 1, the target is instructed to continue tracing if it
3142 loses its connection to GDB. If 0, the target is to stop tracing
3145 set circular-trace-buffer
3146 show circular-trace-buffer
3147 If set to on, the target is instructed to use a circular trace buffer
3148 and discard the oldest trace frames instead of stopping the trace due
3149 to a full trace buffer. If set to off, the trace stops when the buffer
3150 fills up. Some targets may not support this.
3152 set script-extension off|soft|strict
3153 show script-extension
3154 If set to "off", the debugger does not perform any script language
3155 recognition, and all sourced files are assumed to be GDB scripts.
3156 If set to "soft" (the default), files are sourced according to
3157 filename extension, falling back to GDB scripts if the first
3159 If set to "strict", files are sourced according to filename extension.
3161 set ada trust-PAD-over-XVS on|off
3162 show ada trust-PAD-over-XVS
3163 If off, activate a workaround against a bug in the debugging information
3164 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
3165 the GCC sources for more information about the GNAT encoding and
3166 PAD types in particular). It is always safe to set this option to
3167 off, but this introduces a slight performance penalty. The default
3170 * Python API Improvements
3172 ** GDB provides the new class gdb.LazyString. This is useful in
3173 some pretty-printing cases. The new method gdb.Value.lazy_string
3174 provides a simple way to create objects of this type.
3176 ** The fields returned by gdb.Type.fields now have an
3177 `is_base_class' attribute.
3179 ** The new method gdb.Type.range returns the range of an array type.
3181 ** The new method gdb.parse_and_eval can be used to parse and
3182 evaluate an expression.
3184 * New remote packets
3187 Define a trace state variable.
3190 Get the current value of a trace state variable.
3193 Set desired tracing behavior upon disconnection.
3196 Set the trace buffer to be linear or circular.
3199 Get data about the tracepoints currently in use.
3203 Process record now works correctly with hardware watchpoints.
3205 Multiple bug fixes have been made to the mips-irix port, making it
3206 much more reliable. In particular:
3207 - Debugging threaded applications is now possible again. Previously,
3208 GDB would hang while starting the program, or while waiting for
3209 the program to stop at a breakpoint.
3210 - Attaching to a running process no longer hangs.
3211 - An error occurring while loading a core file has been fixed.
3212 - Changing the value of the PC register now works again. This fixes
3213 problems observed when using the "jump" command, or when calling
3214 a function from GDB, or even when assigning a new value to $pc.
3215 - With the "finish" and "return" commands, the return value for functions
3216 returning a small array is now correctly printed.
3217 - It is now possible to break on shared library code which gets executed
3218 during a shared library init phase (code executed while executing
3219 their .init section). Previously, the breakpoint would have no effect.
3220 - GDB is now able to backtrace through the signal handler for
3221 non-threaded programs.
3223 PIE (Position Independent Executable) programs debugging is now supported.
3224 This includes debugging execution of PIC (Position Independent Code) shared
3225 libraries although for that, it should be possible to run such libraries as an
3228 *** Changes in GDB 7.0
3230 * GDB now has an interface for JIT compilation. Applications that
3231 dynamically generate code can create symbol files in memory and register
3232 them with GDB. For users, the feature should work transparently, and
3233 for JIT developers, the interface is documented in the GDB manual in the
3234 "JIT Compilation Interface" chapter.
3236 * Tracepoints may now be conditional. The syntax is as for
3237 breakpoints; either an "if" clause appended to the "trace" command,
3238 or the "condition" command is available. GDB sends the condition to
3239 the target for evaluation using the same bytecode format as is used
3240 for tracepoint actions.
3242 * The disassemble command now supports: an optional /r modifier, print the
3243 raw instructions in hex as well as in symbolic form, and an optional /m
3244 modifier to print mixed source+assembly.
3246 * Process record and replay
3248 In a architecture environment that supports ``process record and
3249 replay'', ``process record and replay'' target can record a log of
3250 the process execution, and replay it with both forward and reverse
3253 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3254 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3255 set execution-direction {forward|reverse}, for targets that support
3258 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3259 feature is available with a native GDB running on kernel version
3262 * GDB now has support for multi-byte and wide character sets on the
3263 target. Strings whose character type is wchar_t, char16_t, or
3264 char32_t are now correctly printed. GDB supports wide- and unicode-
3265 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3266 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3267 `printf'. This feature requires iconv to work properly; if your
3268 system does not have a working iconv, GDB can use GNU libiconv. See
3269 the installation instructions for more information.
3271 * GDB now supports automatic retrieval of shared library files from
3272 remote targets. To use this feature, specify a system root that begins
3273 with the `remote:' prefix, either via the `set sysroot' command or via
3274 the `--with-sysroot' configure-time option.
3276 * "info sharedlibrary" now takes an optional regex of libraries to show,
3277 and it now reports if a shared library has no debugging information.
3279 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3280 now complete on file names.
3282 * When completing in expressions, gdb will attempt to limit
3283 completions to allowable structure or union fields, where appropriate.
3284 For instance, consider:
3286 # struct example { int f1; double f2; };
3287 # struct example variable;
3290 If the user types TAB at the end of this command line, the available
3291 completions will be "f1" and "f2".
3293 * Inlined functions are now supported. They show up in backtraces, and
3294 the "step", "next", and "finish" commands handle them automatically.
3296 * GDB now supports the token-splicing (##) and stringification (#)
3297 operators when expanding macros. It also supports variable-arity
3300 * GDB now supports inspecting extra signal information, exported by
3301 the new $_siginfo convenience variable. The feature is currently
3302 implemented on linux ARM, i386 and amd64.
3304 * GDB can now display the VFP floating point registers and NEON vector
3305 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3306 can provide these registers (requires Linux 2.6.30 or later). Remote
3307 and simulator targets may also provide them.
3309 * New remote packets
3312 Search memory for a sequence of bytes.
3315 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3316 operation over reliable transport links. Use of this packet is
3317 controlled by the `set remote noack-packet' command.
3320 Kill the process with the specified process ID. Use this in preference
3321 to `k' when multiprocess protocol extensions are supported.
3324 Obtains additional operating system information
3328 Read or write additional signal information.
3330 * Removed remote protocol undocumented extension
3332 An undocumented extension to the remote protocol's `S' stop reply
3333 packet that permited the stub to pass a process id was removed.
3334 Remote servers should use the `T' stop reply packet instead.
3336 * GDB now supports multiple function calling conventions according to the
3337 DWARF-2 DW_AT_calling_convention function attribute.
3339 * The SH target utilizes the aforementioned change to distinguish between gcc
3340 and Renesas calling convention. It also adds the new CLI commands
3341 `set/show sh calling-convention'.
3343 * GDB can now read compressed debug sections, as produced by GNU gold
3344 with the --compress-debug-sections=zlib flag.
3346 * 64-bit core files are now supported on AIX.
3348 * Thread switching is now supported on Tru64.
3350 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3351 which will be allocated using malloc later in program execution.
3353 * The qXfer:libraries:read remote procotol packet now allows passing a
3354 list of section offsets.
3356 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3357 conditions handling signals delivered during attach or thread creation
3358 have also been fixed.
3360 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3361 From the user's standpoint, all unqualified instances of True and False
3362 are treated as the standard definitions, regardless of context.
3364 * GDB now parses C++ symbol and type names more flexibly. For
3367 template<typename T> class C { };
3370 GDB will now correctly handle all of:
3372 ptype C<char const *>
3373 ptype C<char const*>
3374 ptype C<const char *>
3375 ptype C<const char*>
3377 * New features in the GDB remote stub, gdbserver
3379 - The "--wrapper" command-line argument tells gdbserver to use a
3380 wrapper program to launch programs for debugging.
3382 - On PowerPC and S/390 targets, it is now possible to use a single
3383 gdbserver executable to debug both 32-bit and 64-bit programs.
3384 (This requires gdbserver itself to be built as a 64-bit executable.)
3386 - gdbserver uses the new noack protocol mode for TCP connections to
3387 reduce communications latency, if also supported and enabled in GDB.
3389 - Support for the sparc64-linux-gnu target is now included in
3392 - The amd64-linux build of gdbserver now supports debugging both
3393 32-bit and 64-bit programs.
3395 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3396 now support hardware watchpoints, and will use them automatically
3401 GDB now has support for scripting using Python. Whether this is
3402 available is determined at configure time.
3404 New GDB commands can now be written in Python.
3406 * Ada tasking support
3408 Ada tasks can now be inspected in GDB. The following commands have
3412 Print the list of Ada tasks.
3414 Print detailed information about task number N.
3416 Print the task number of the current task.
3418 Switch the context of debugging to task number N.
3420 * Support for user-defined prefixed commands. The "define" command can
3421 add new commands to existing prefixes, e.g. "target".
3423 * Multi-inferior, multi-process debugging.
3425 GDB now has generalized support for multi-inferior debugging. See
3426 "Debugging Multiple Inferiors" in the manual for more information.
3427 Although availability still depends on target support, the command
3428 set is more uniform now. The GNU/Linux specific multi-forks support
3429 has been migrated to this new framework. This implied some user
3430 visible changes; see "New commands" and also "Removed commands"
3433 * Target descriptions can now describe the target OS ABI. See the
3434 "Target Description Format" section in the user manual for more
3437 * Target descriptions can now describe "compatible" architectures
3438 to indicate that the target can execute applications for a different
3439 architecture in addition to those for the main target architecture.
3440 See the "Target Description Format" section in the user manual for
3443 * Multi-architecture debugging.
3445 GDB now includes general supports for debugging applications on
3446 hybrid systems that use more than one single processor architecture
3447 at the same time. Each such hybrid architecture still requires
3448 specific support to be added. The only hybrid architecture supported
3449 in this version of GDB is the Cell Broadband Engine.
3451 * GDB now supports integrated debugging of Cell/B.E. applications that
3452 use both the PPU and SPU architectures. To enable support for hybrid
3453 Cell/B.E. debugging, you need to configure GDB to support both the
3454 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3455 --enable-targets configure option.
3457 * Non-stop mode debugging.
3459 For some targets, GDB now supports an optional mode of operation in
3460 which you can examine stopped threads while other threads continue
3461 to execute freely. This is referred to as non-stop mode, with the
3462 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3463 section in the user manual for more information.
3465 To be able to support remote non-stop debugging, a remote stub needs
3466 to implement the non-stop mode remote protocol extensions, as
3467 described in the "Remote Non-Stop" section of the user manual. The
3468 GDB remote stub, gdbserver, has been adjusted to support these
3469 extensions on linux targets.
3471 * New commands (for set/show, see "New options" below)
3473 catch syscall [NAME(S) | NUMBER(S)]
3474 Catch system calls. Arguments, which should be names of system
3475 calls or their numbers, mean catch only those syscalls. Without
3476 arguments, every syscall will be caught. When the inferior issues
3477 any of the specified syscalls, GDB will stop and announce the system
3478 call, both when it is called and when its call returns. This
3479 feature is currently available with a native GDB running on the
3480 Linux Kernel, under the following architectures: x86, x86_64,
3481 PowerPC and PowerPC64.
3483 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3485 Search memory for a sequence of bytes.
3487 maint set python print-stack
3488 maint show python print-stack
3489 Show a stack trace when an error is encountered in a Python script.
3492 Invoke CODE by passing it to the Python interpreter.
3497 These allow macros to be defined, undefined, and listed
3501 Show operating system information about processes.
3504 List the inferiors currently under GDB's control.
3507 Switch focus to inferior number NUM.
3510 Detach from inferior number NUM.
3513 Kill inferior number NUM.
3517 set spu stop-on-load
3518 show spu stop-on-load
3519 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3521 set spu auto-flush-cache
3522 show spu auto-flush-cache
3523 Control whether to automatically flush the software-managed cache
3524 during Cell/B.E. debugging.
3526 set sh calling-convention
3527 show sh calling-convention
3528 Control the calling convention used when calling SH target functions.
3531 show debug timestamp
3532 Control display of timestamps with GDB debugging output.
3534 set disassemble-next-line
3535 show disassemble-next-line
3536 Control display of disassembled source lines or instructions when
3539 set remote noack-packet
3540 show remote noack-packet
3541 Set/show the use of remote protocol QStartNoAckMode packet. See above
3542 under "New remote packets."
3544 set remote query-attached-packet
3545 show remote query-attached-packet
3546 Control use of remote protocol `qAttached' (query-attached) packet.
3548 set remote read-siginfo-object
3549 show remote read-siginfo-object
3550 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3553 set remote write-siginfo-object
3554 show remote write-siginfo-object
3555 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3558 set remote reverse-continue
3559 show remote reverse-continue
3560 Control use of remote protocol 'bc' (reverse-continue) packet.
3562 set remote reverse-step
3563 show remote reverse-step
3564 Control use of remote protocol 'bs' (reverse-step) packet.
3566 set displaced-stepping
3567 show displaced-stepping
3568 Control displaced stepping mode. Displaced stepping is a way to
3569 single-step over breakpoints without removing them from the debuggee.
3570 Also known as "out-of-line single-stepping".
3573 show debug displaced
3574 Control display of debugging info for displaced stepping.
3576 maint set internal-error
3577 maint show internal-error
3578 Control what GDB does when an internal error is detected.
3580 maint set internal-warning
3581 maint show internal-warning
3582 Control what GDB does when an internal warning is detected.
3587 Use a wrapper program to launch programs for debugging.
3589 set multiple-symbols (all|ask|cancel)
3590 show multiple-symbols
3591 The value of this variable can be changed to adjust the debugger behavior
3592 when an expression or a breakpoint location contains an ambiguous symbol
3593 name (an overloaded function name, for instance).
3595 set breakpoint always-inserted
3596 show breakpoint always-inserted
3597 Keep breakpoints always inserted in the target, as opposed to inserting
3598 them when resuming the target, and removing them when the target stops.
3599 This option can improve debugger performance on slow remote targets.
3601 set arm fallback-mode (arm|thumb|auto)
3602 show arm fallback-mode
3603 set arm force-mode (arm|thumb|auto)
3605 These commands control how ARM GDB determines whether instructions
3606 are ARM or Thumb. The default for both settings is auto, which uses
3607 the current CPSR value for instructions without symbols; previous
3608 versions of GDB behaved as if "set arm fallback-mode arm".
3610 set disable-randomization
3611 show disable-randomization
3612 Standalone programs run with the virtual address space randomization enabled
3613 by default on some platforms. This option keeps the addresses stable across
3614 multiple debugging sessions.
3618 Control whether other threads are stopped or not when some thread hits
3623 Requests that asynchronous execution is enabled in the target, if available.
3624 In this case, it's possible to resume target in the background, and interact
3625 with GDB while the target is running. "show target-async" displays the
3626 current state of asynchronous execution of the target.
3628 set target-wide-charset
3629 show target-wide-charset
3630 The target-wide-charset is the name of the character set that GDB
3631 uses when printing characters whose type is wchar_t.
3633 set tcp auto-retry (on|off)
3635 set tcp connect-timeout
3636 show tcp connect-timeout
3637 These commands allow GDB to retry failed TCP connections to a remote stub
3638 with a specified timeout period; this is useful if the stub is launched
3639 in parallel with GDB but may not be ready to accept connections immediately.
3641 set libthread-db-search-path
3642 show libthread-db-search-path
3643 Control list of directories which GDB will search for appropriate
3646 set schedule-multiple (on|off)
3647 show schedule-multiple
3648 Allow GDB to resume all threads of all processes or only threads of
3649 the current process.
3653 Use more aggressive caching for accesses to the stack. This improves
3654 performance of remote debugging (particularly backtraces) without
3655 affecting correctness.
3657 set interactive-mode (on|off|auto)
3658 show interactive-mode
3659 Control whether GDB runs in interactive mode (on) or not (off).
3660 When in interactive mode, GDB waits for the user to answer all
3661 queries. Otherwise, GDB does not wait and assumes the default
3662 answer. When set to auto (the default), GDB determines which
3663 mode to use based on the stdin settings.
3668 For program forks, this is replaced by the new more generic `info
3669 inferiors' command. To list checkpoints, you can still use the
3670 `info checkpoints' command, which was an alias for the `info forks'
3674 Replaced by the new `inferior' command. To switch between
3675 checkpoints, you can still use the `restart' command, which was an
3676 alias for the `fork' command.
3679 This is removed, since some targets don't have a notion of
3680 processes. To switch between processes, you can still use the
3681 `inferior' command using GDB's own inferior number.
3684 For program forks, this is replaced by the new more generic `kill
3685 inferior' command. To delete a checkpoint, you can still use the
3686 `delete checkpoint' command, which was an alias for the `delete
3690 For program forks, this is replaced by the new more generic `detach
3691 inferior' command. To detach a checkpoint, you can still use the
3692 `detach checkpoint' command, which was an alias for the `detach
3695 * New native configurations
3697 x86/x86_64 Darwin i[34567]86-*-darwin*
3699 x86_64 MinGW x86_64-*-mingw*
3703 Lattice Mico32 lm32-*
3704 x86 DICOS i[34567]86-*-dicos*
3705 x86_64 DICOS x86_64-*-dicos*
3708 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3709 (mingw32ce) debugging.
3715 These commands were actually not implemented on any target.
3717 *** Changes in GDB 6.8
3719 * New native configurations
3721 NetBSD/hppa hppa*-*netbsd*
3722 Xtensa GNU/Linux xtensa*-*-linux*
3726 NetBSD/hppa hppa*-*-netbsd*
3727 Xtensa GNU/Lunux xtensa*-*-linux*
3729 * Change in command line behavior -- corefiles vs. process ids.
3731 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3732 attaching to process NUMBER fails, GDB no longer attempts to open a
3733 core file named NUMBER. Attaching to a program using the -c option
3734 is no longer supported. Instead, use the '-p' or '--pid' options.
3736 * GDB can now be built as a native debugger for debugging Windows x86
3737 (mingw32) Portable Executable (PE) programs.
3739 * Pending breakpoints no longer change their number when their address
3742 * GDB now supports breakpoints with multiple locations,
3743 including breakpoints on C++ constructors, inside C++ templates,
3744 and in inlined functions.
3746 * GDB's ability to debug optimized code has been improved. GDB more
3747 accurately identifies function bodies and lexical blocks that occupy
3748 more than one contiguous range of addresses.
3750 * Target descriptions can now describe registers for PowerPC.
3752 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3753 registers on PowerPC targets.
3755 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3756 targets even when the libthread_db library is not available.
3758 * The GDB remote stub, gdbserver, now supports the new file transfer
3759 commands (remote put, remote get, and remote delete).
3761 * The GDB remote stub, gdbserver, now supports run and attach in
3762 extended-remote mode.
3764 * hppa*64*-*-hpux11* target broken
3765 The debugger is unable to start a program and fails with the following
3766 error: "Error trying to get information about dynamic linker".
3767 The gdb-6.7 release is also affected.
3769 * GDB now supports the --enable-targets= configure option to allow
3770 building a single GDB executable that supports multiple remote
3771 target architectures.
3773 * GDB now supports debugging C and C++ programs which use the
3774 Decimal Floating Point extension. In addition, the PowerPC target
3775 now has a set of pseudo-registers to inspect decimal float values
3776 stored in two consecutive float registers.
3778 * The -break-insert MI command can optionally create pending
3781 * Improved support for debugging Ada
3782 Many improvements to the Ada language support have been made. These
3784 - Better support for Ada2005 interface types
3785 - Improved handling of arrays and slices in general
3786 - Better support for Taft-amendment types
3787 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3789 - Improved command completion in Ada
3792 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3797 set print frame-arguments (all|scalars|none)
3798 show print frame-arguments
3799 The value of this variable can be changed to control which argument
3800 values should be printed by the debugger when displaying a frame.
3805 Transfer files to and from a remote target, and delete remote files.
3812 Transfer files to and from a remote target, and delete remote files.
3814 * New remote packets
3821 Open, close, read, write, and delete files on the remote system.
3824 Attach to an existing process on the remote system, in extended-remote
3828 Run a new process on the remote system, in extended-remote mode.
3830 *** Changes in GDB 6.7
3832 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3833 bfd, libiberty and opcodes, as revealed by static analysis donated by
3834 Coverity, Inc. (http://scan.coverity.com).
3836 * When looking up multiply-defined global symbols, GDB will now prefer the
3837 symbol definition in the current shared library if it was built using the
3838 -Bsymbolic linker option.
3840 * When the Text User Interface (TUI) is not configured, GDB will now
3841 recognize the -tui command-line option and print a message that the TUI
3844 * The GDB remote stub, gdbserver, now has lower overhead for high
3845 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3847 * GDB for MIPS targets now autodetects whether a remote target provides
3848 32-bit or 64-bit register values.
3850 * Support for C++ member pointers has been improved.
3852 * GDB now understands XML target descriptions, which specify the
3853 target's overall architecture. GDB can read a description from
3854 a local file or over the remote serial protocol.
3856 * Vectors of single-byte data use a new integer type which is not
3857 automatically displayed as character or string data.
3859 * The /s format now works with the print command. It displays
3860 arrays of single-byte integers and pointers to single-byte integers
3863 * Target descriptions can now describe target-specific registers,
3864 for architectures which have implemented the support (currently
3865 only ARM, M68K, and MIPS).
3867 * GDB and the GDB remote stub, gdbserver, now support the XScale
3870 * The GDB remote stub, gdbserver, has been updated to support
3871 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3872 has been rewritten to use the standard GDB remote protocol.
3874 * GDB can now step into C++ functions which are called through thunks.
3876 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3878 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3879 layout. It also supports a TextSeg= and DataSeg= response when only
3880 segment base addresses (rather than offsets) are available.
3882 * The /i format now outputs any trailing branch delay slot instructions
3883 immediately following the last instruction within the count specified.
3885 * The GDB remote protocol "T" stop reply packet now supports a
3886 "library" response. Combined with the new "qXfer:libraries:read"
3887 packet, this response allows GDB to debug shared libraries on targets
3888 where the operating system manages the list of loaded libraries (e.g.
3889 Windows and SymbianOS).
3891 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3892 (DLLs) on Windows and Windows CE targets.
3894 * GDB now supports a faster verification that a .debug file matches its binary
3895 according to its build-id signature, if the signature is present.
3901 Enable or disable hardware flow control (RTS/CTS) on the serial port
3902 when debugging using remote targets.
3904 set mem inaccessible-by-default
3905 show mem inaccessible-by-default
3906 If the target supplies a memory map, for instance via the remote
3907 protocol's "qXfer:memory-map:read" packet, setting this variable
3908 prevents GDB from accessing memory outside the memory map. This
3909 is useful for targets with memory mapped registers or which react
3910 badly to accesses of unmapped address space.
3912 set breakpoint auto-hw
3913 show breakpoint auto-hw
3914 If the target supplies a memory map, for instance via the remote
3915 protocol's "qXfer:memory-map:read" packet, setting this variable
3916 lets GDB use hardware breakpoints automatically for memory regions
3917 where it can not use software breakpoints. This covers both the
3918 "break" command and internal breakpoints used for other commands
3919 including "next" and "finish".
3922 catch exception unhandled
3923 Stop the program execution when Ada exceptions are raised.
3926 Stop the program execution when an Ada assertion failed.
3930 Set an alternate system root for target files. This is a more
3931 general version of "set solib-absolute-prefix", which is now
3932 an alias to "set sysroot".
3935 Provide extended SPU facility status information. This set of
3936 commands is available only when debugging the Cell/B.E. SPU
3939 * New native configurations
3941 OpenBSD/sh sh*-*openbsd*
3944 unset tdesc filename
3946 Use the specified local file as an XML target description, and do
3947 not query the target for its built-in description.
3951 OpenBSD/sh sh*-*-openbsd*
3952 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3953 Toshiba Media Processor mep-elf
3955 * New remote packets
3958 Ignore the specified signals; pass them directly to the debugged program
3959 without stopping other threads or reporting them to GDB.
3961 qXfer:features:read:
3962 Read an XML target description from the target, which describes its
3967 Read or write contents of an spufs file on the target system. These
3968 packets are available only on the Cell/B.E. SPU architecture.
3970 qXfer:libraries:read:
3971 Report the loaded shared libraries. Combined with new "T" packet
3972 response, this packet allows GDB to debug shared libraries on
3973 targets where the operating system manages the list of loaded
3974 libraries (e.g. Windows and SymbianOS).
3978 Support for these obsolete configurations has been removed.
3986 i[34567]86-*-lynxos*
3987 i[34567]86-*-netware*
3988 i[34567]86-*-sco3.2v5*
3989 i[34567]86-*-sco3.2v4*
3991 i[34567]86-*-sysv4.2*
3994 i[34567]86-*-unixware2*
3995 i[34567]86-*-unixware*
4004 * Other removed features
4011 Various m68k-only ROM monitors.
4018 Various Renesas ROM monitors and debugging interfaces for SH and
4023 Support for a Macraigor serial interface to on-chip debugging.
4024 GDB does not directly support the newer parallel or USB
4029 A debug information format. The predecessor to DWARF 2 and
4030 DWARF 3, which are still supported.
4032 Support for the HP aCC compiler on HP-UX/PA-RISC
4034 SOM-encapsulated symbolic debugging information, automatic
4035 invocation of pxdb, and the aCC custom C++ ABI. This does not
4036 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
4037 with aCC can still be debugged on an assembly level.
4039 MIPS ".pdr" sections
4041 A MIPS-specific format used to describe stack frame layout
4042 in debugging information.
4046 GDB could work with an older version of Guile to debug
4047 the interpreter and Scheme programs running in it.
4049 set mips stack-arg-size
4050 set mips saved-gpreg-size
4052 Use "set mips abi" to control parameter passing for MIPS.
4054 *** Changes in GDB 6.6
4059 Cell Broadband Engine SPU spu-elf
4061 * GDB can now be configured as a cross-debugger targeting native Windows
4062 (mingw32) or Cygwin. It can communicate with a remote debugging stub
4063 running on a Windows system over TCP/IP to debug Windows programs.
4065 * The GDB remote stub, gdbserver, has been updated to support Windows and
4066 Cygwin debugging. Both single-threaded and multi-threaded programs are
4069 * The "set trust-readonly-sections" command works again. This command was
4070 broken in GDB 6.3, 6.4, and 6.5.
4072 * The "load" command now supports writing to flash memory, if the remote
4073 stub provides the required support.
4075 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
4076 longer requires symbolic debug information (e.g. DWARF-2).
4081 unset substitute-path
4082 show substitute-path
4083 Manage a list of substitution rules that GDB uses to rewrite the name
4084 of the directories where the sources are located. This can be useful
4085 for instance when the sources were moved to a different location
4086 between compilation and debugging.
4090 Print each CLI command as it is executed. Each command is prefixed with
4091 a number of `+' symbols representing the nesting depth.
4092 The source command now has a `-v' option to enable the same feature.
4096 The ARM Demon monitor support (RDP protocol, "target rdp").
4098 Kernel Object Display, an embedded debugging feature which only worked with
4099 an obsolete version of Cisco IOS.
4101 The 'set download-write-size' and 'show download-write-size' commands.
4103 * New remote packets
4106 Tell a stub about GDB client features, and request remote target features.
4107 The first feature implemented is PacketSize, which allows the target to
4108 specify the size of packets it can handle - to minimize the number of
4109 packets required and improve performance when connected to a remote
4113 Fetch an OS auxilliary vector from the remote stub. This packet is a
4114 more efficient replacement for qPart:auxv:read.
4116 qXfer:memory-map:read:
4117 Fetch a memory map from the remote stub, including information about
4118 RAM, ROM, and flash memory devices.
4123 Erase and program a flash memory device.
4125 * Removed remote packets
4128 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
4129 used it, and only gdbserver implemented it.
4131 *** Changes in GDB 6.5
4135 Renesas M32C/M16C m32c-elf
4137 Morpho Technologies ms1 ms1-elf
4141 init-if-undefined Initialize a convenience variable, but
4142 only if it doesn't already have a value.
4144 The following commands are presently only implemented for native GNU/Linux:
4146 checkpoint Save a snapshot of the program state.
4148 restart <n> Return the program state to a
4149 previously saved state.
4151 info checkpoints List currently saved checkpoints.
4153 delete-checkpoint <n> Delete a previously saved checkpoint.
4155 set|show detach-on-fork Tell gdb whether to detach from a newly
4156 forked process, or to keep debugging it.
4158 info forks List forks of the user program that
4159 are available to be debugged.
4161 fork <n> Switch to debugging one of several
4162 forks of the user program that are
4163 available to be debugged.
4165 delete-fork <n> Delete a fork from the list of forks
4166 that are available to be debugged (and
4167 kill the forked process).
4169 detach-fork <n> Delete a fork from the list of forks
4170 that are available to be debugged (and
4171 allow the process to continue).
4175 Morpho Technologies ms2 ms1-elf
4177 * Improved Windows host support
4179 GDB now builds as a cross debugger hosted on i686-mingw32, including
4180 native console support, and remote communications using either
4181 network sockets or serial ports.
4183 * Improved Modula-2 language support
4185 GDB can now print most types in the Modula-2 syntax. This includes:
4186 basic types, set types, record types, enumerated types, range types,
4187 pointer types and ARRAY types. Procedure var parameters are correctly
4188 printed and hexadecimal addresses and character constants are also
4189 written in the Modula-2 syntax. Best results can be obtained by using
4190 GNU Modula-2 together with the -gdwarf-2 command line option.
4194 The ARM rdi-share module.
4196 The Netware NLM debug server.
4198 *** Changes in GDB 6.4
4200 * New native configurations
4202 OpenBSD/arm arm*-*-openbsd*
4203 OpenBSD/mips64 mips64-*-openbsd*
4207 Morpho Technologies ms1 ms1-elf
4209 * New command line options
4211 --batch-silent As for --batch, but totally silent.
4212 --return-child-result The debugger will exist with the same value
4213 the child (debugged) program exited with.
4214 --eval-command COMMAND, -ex COMMAND
4215 Execute a single GDB CLI command. This may be
4216 specified multiple times and in conjunction
4217 with the --command (-x) option.
4219 * Deprecated commands removed
4221 The following commands, that were deprecated in 2000, have been
4225 set|show arm disassembly-flavor set|show arm disassembler
4226 othernames set arm disassembler
4227 set|show remotedebug set|show debug remote
4228 set|show archdebug set|show debug arch
4229 set|show eventdebug set|show debug event
4232 * New BSD user-level threads support
4234 It is now possible to debug programs using the user-level threads
4235 library on OpenBSD and FreeBSD. Currently supported (target)
4238 FreeBSD/amd64 x86_64-*-freebsd*
4239 FreeBSD/i386 i386-*-freebsd*
4240 OpenBSD/i386 i386-*-openbsd*
4242 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4243 are not yet supported.
4245 * New support for Matsushita MN10300 w/sim added
4246 (Work in progress). mn10300-elf.
4248 * REMOVED configurations and files
4250 VxWorks and the XDR protocol *-*-vxworks
4251 Motorola MCORE mcore-*-*
4252 National Semiconductor NS32000 ns32k-*-*
4254 * New "set print array-indexes" command
4256 After turning this setting "on", GDB prints the index of each element
4257 when displaying arrays. The default is "off" to preserve the previous
4260 * VAX floating point support
4262 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4264 * User-defined command support
4266 In addition to using $arg0..$arg9 for argument passing, it is now possible
4267 to use $argc to determine now many arguments have been passed. See the
4268 section on user-defined commands in the user manual for more information.
4270 *** Changes in GDB 6.3:
4272 * New command line option
4274 GDB now accepts -l followed by a number to set the timeout for remote
4277 * GDB works with GCC -feliminate-dwarf2-dups
4279 GDB now supports a more compact representation of DWARF-2 debug
4280 information using DW_FORM_ref_addr references. These are produced
4281 by GCC with the option -feliminate-dwarf2-dups and also by some
4282 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4283 to use -feliminate-dwarf2-dups.
4285 * Internationalization
4287 When supported by the host system, GDB will be built with
4288 internationalization (libintl). The task of marking up the sources is
4289 continued, we're looking forward to our first translation.
4293 Initial support for debugging programs compiled with the GNAT
4294 implementation of the Ada programming language has been integrated
4295 into GDB. In this release, support is limited to expression evaluation.
4297 * New native configurations
4299 GNU/Linux/m32r m32r-*-linux-gnu
4303 GDB's remote protocol now includes support for the 'p' packet. This
4304 packet is used to fetch individual registers from a remote inferior.
4306 * END-OF-LIFE registers[] compatibility module
4308 GDB's internal register infrastructure has been completely rewritten.
4309 The new infrastructure making possible the implementation of key new
4310 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4313 GDB 6.3 will be the last release to include the the registers[]
4314 compatibility module that allowed out-of-date configurations to
4315 continue to work. This change directly impacts the following
4325 powerpc bdm protocol
4327 Unless there is activity to revive these configurations, they will be
4328 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4330 * OBSOLETE configurations and files
4332 Configurations that have been declared obsolete in this release have
4333 been commented out. Unless there is activity to revive these
4334 configurations, the next release of GDB will have their sources
4335 permanently REMOVED.
4344 *** Changes in GDB 6.2.1:
4346 * MIPS `break main; run' gave an heuristic-fence-post warning
4348 When attempting to run even a simple program, a warning about
4349 heuristic-fence-post being hit would be reported. This problem has
4352 * MIPS IRIX 'long double' crashed GDB
4354 When examining a long double variable, GDB would get a segmentation
4355 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4356 IRIX long double values).
4360 A bug in the VAX stack code was causing problems with the "next"
4361 command. This problem has been fixed.
4363 *** Changes in GDB 6.2:
4365 * Fix for ``many threads''
4367 On GNU/Linux systems that use the NPTL threads library, a program
4368 rapidly creating and deleting threads would confuse GDB leading to the
4371 ptrace: No such process.
4372 thread_db_get_info: cannot get thread info: generic error
4374 This problem has been fixed.
4376 * "-async" and "-noasync" options removed.
4378 Support for the broken "-noasync" option has been removed (it caused
4381 * New ``start'' command.
4383 This command runs the program until the begining of the main procedure.
4385 * New BSD Kernel Data Access Library (libkvm) interface
4387 Using ``target kvm'' it is now possible to debug kernel core dumps and
4388 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4389 platforms. Currently supported (native-only) configurations are:
4391 FreeBSD/amd64 x86_64-*-freebsd*
4392 FreeBSD/i386 i?86-*-freebsd*
4393 NetBSD/i386 i?86-*-netbsd*
4394 NetBSD/m68k m68*-*-netbsd*
4395 NetBSD/sparc sparc-*-netbsd*
4396 OpenBSD/amd64 x86_64-*-openbsd*
4397 OpenBSD/i386 i?86-*-openbsd*
4398 OpenBSD/m68k m68*-openbsd*
4399 OpenBSD/sparc sparc-*-openbsd*
4401 * Signal trampoline code overhauled
4403 Many generic problems with GDB's signal handling code have been fixed.
4404 These include: backtraces through non-contiguous stacks; recognition
4405 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4406 call; backtrace through a signal trampoline; step into and out of
4407 signal handlers; and single-stepping in the signal trampoline.
4409 Please note that kernel bugs are a limiting factor here. These
4410 features have been shown to work on an s390 GNU/Linux system that
4411 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4413 * Cygwin support for DWARF 2 added.
4415 * New native configurations
4417 GNU/Linux/hppa hppa*-*-linux*
4418 OpenBSD/hppa hppa*-*-openbsd*
4419 OpenBSD/m68k m68*-*-openbsd*
4420 OpenBSD/m88k m88*-*-openbsd*
4421 OpenBSD/powerpc powerpc-*-openbsd*
4422 NetBSD/vax vax-*-netbsd*
4423 OpenBSD/vax vax-*-openbsd*
4425 * END-OF-LIFE frame compatibility module
4427 GDB's internal frame infrastructure has been completely rewritten.
4428 The new infrastructure making it possible to support key new features
4429 including DWARF 2 Call Frame Information. To aid in the task of
4430 migrating old configurations to this new infrastructure, a
4431 compatibility module, that allowed old configurations to continue to
4432 work, was also included.
4434 GDB 6.2 will be the last release to include this frame compatibility
4435 module. This change directly impacts the following configurations:
4445 Unless there is activity to revive these configurations, they will be
4446 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4448 * REMOVED configurations and files
4450 Sun 3, running SunOS 3 m68*-*-sunos3*
4451 Sun 3, running SunOS 4 m68*-*-sunos4*
4452 Sun 2, running SunOS 3 m68000-*-sunos3*
4453 Sun 2, running SunOS 4 m68000-*-sunos4*
4454 Motorola 680x0 running LynxOS m68*-*-lynxos*
4455 AT&T 3b1/Unix pc m68*-att-*
4456 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4457 decstation mips-dec-* mips-little-*
4458 riscos mips-*-riscos* mips-*-sysv*
4459 sonymips mips-sony-*
4460 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4462 *** Changes in GDB 6.1.1:
4464 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4466 The TUI (Text-mode User Interface) is now built as part of a default
4467 GDB configuration. It is enabled by either selecting the TUI with the
4468 command line option "-i=tui" or by running the separate "gdbtui"
4469 program. For more information on the TUI, see the manual "Debugging
4472 * Pending breakpoint support (also included in GDB 6.1)
4474 Support has been added to allow you to specify breakpoints in shared
4475 libraries that have not yet been loaded. If a breakpoint location
4476 cannot be found, and the "breakpoint pending" option is set to auto,
4477 GDB queries you if you wish to make the breakpoint pending on a future
4478 shared-library load. If and when GDB resolves the breakpoint symbol,
4479 the pending breakpoint is removed as one or more regular breakpoints
4482 Pending breakpoints are very useful for GCJ Java debugging.
4484 * Fixed ISO-C build problems
4486 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4487 non ISO-C code that stopped them being built using a more strict ISO-C
4488 compiler (e.g., IBM's C compiler).
4490 * Fixed build problem on IRIX 5
4492 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4493 wasn't able to compile compile on an IRIX 5 system.
4495 * Added execute permission to gdb/gdbserver/configure
4497 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4498 permission. This bug would cause configure to fail on a number of
4499 systems (Solaris, IRIX). Ref: server/519.
4501 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4503 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4504 has been updated to use constant array sizes.
4506 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4508 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4509 its generated DWARF Call Frame Info. This encoding was causing GDB to
4510 panic, that panic has been fixed. Ref: gdb/1628.
4512 * Fixed a problem when examining parameters in shared library code.
4514 When examining parameters in optimized shared library code generated
4515 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4516 not available''. GDB now correctly displays the variable's value.
4518 *** Changes in GDB 6.1:
4520 * Removed --with-mmalloc
4522 Support for the mmalloc memory manager has been removed, as it
4523 conflicted with the internal gdb byte cache.
4525 * Changes in AMD64 configurations
4527 The AMD64 target now includes the %cs and %ss registers. As a result
4528 the AMD64 remote protocol has changed; this affects the floating-point
4529 and SSE registers. If you rely on those registers for your debugging,
4530 you should upgrade gdbserver on the remote side.
4532 * Revised SPARC target
4534 The SPARC target has been completely revised, incorporating the
4535 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4536 support for LynxOS and SunOS 4 has been dropped. Calling functions
4537 from within GDB on operating systems with a non-executable stack
4538 (Solaris, OpenBSD) now works.
4542 GDB has a new C++ demangler which does a better job on the mangled
4543 names generated by current versions of g++. It also runs faster, so
4544 with this and other changes gdb should now start faster on large C++
4547 * DWARF 2 Location Expressions
4549 GDB support for location expressions has been extended to support function
4550 arguments and frame bases. Older versions of GDB could crash when they
4553 * C++ nested types and namespaces
4555 GDB's support for nested types and namespaces in C++ has been
4556 improved, especially if you use the DWARF 2 debugging format. (This
4557 is the default for recent versions of GCC on most platforms.)
4558 Specifically, if you have a class "Inner" defined within a class or
4559 namespace "Outer", then GDB realizes that the class's name is
4560 "Outer::Inner", not simply "Inner". This should greatly reduce the
4561 frequency of complaints about not finding RTTI symbols. In addition,
4562 if you are stopped at inside of a function defined within a namespace,
4563 GDB modifies its name lookup accordingly.
4565 * New native configurations
4567 NetBSD/amd64 x86_64-*-netbsd*
4568 OpenBSD/amd64 x86_64-*-openbsd*
4569 OpenBSD/alpha alpha*-*-openbsd*
4570 OpenBSD/sparc sparc-*-openbsd*
4571 OpenBSD/sparc64 sparc64-*-openbsd*
4573 * New debugging protocols
4575 M32R with SDI protocol m32r-*-elf*
4577 * "set prompt-escape-char" command deleted.
4579 The command "set prompt-escape-char" has been deleted. This command,
4580 and its very obscure effet on GDB's prompt, was never documented,
4581 tested, nor mentioned in the NEWS file.
4583 * OBSOLETE configurations and files
4585 Configurations that have been declared obsolete in this release have
4586 been commented out. Unless there is activity to revive these
4587 configurations, the next release of GDB will have their sources
4588 permanently REMOVED.
4590 Sun 3, running SunOS 3 m68*-*-sunos3*
4591 Sun 3, running SunOS 4 m68*-*-sunos4*
4592 Sun 2, running SunOS 3 m68000-*-sunos3*
4593 Sun 2, running SunOS 4 m68000-*-sunos4*
4594 Motorola 680x0 running LynxOS m68*-*-lynxos*
4595 AT&T 3b1/Unix pc m68*-att-*
4596 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4597 decstation mips-dec-* mips-little-*
4598 riscos mips-*-riscos* mips-*-sysv*
4599 sonymips mips-sony-*
4600 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4602 * REMOVED configurations and files
4604 SGI Irix-4.x mips-sgi-irix4 or iris4
4605 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4606 Z8000 simulator z8k-zilog-none or z8ksim
4607 Matsushita MN10200 w/simulator mn10200-*-*
4608 H8/500 simulator h8500-hitachi-hms or h8500hms
4609 HP/PA running BSD hppa*-*-bsd*
4610 HP/PA running OSF/1 hppa*-*-osf*
4611 HP/PA Pro target hppa*-*-pro*
4612 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4613 386BSD i[3456]86-*-bsd*
4614 Sequent family i[3456]86-sequent-sysv4*
4615 i[3456]86-sequent-sysv*
4616 i[3456]86-sequent-bsd*
4617 SPARC running LynxOS sparc-*-lynxos*
4618 SPARC running SunOS 4 sparc-*-sunos4*
4619 Tsqware Sparclet sparclet-*-*
4620 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4622 *** Changes in GDB 6.0:
4626 Support for debugging the Objective-C programming language has been
4627 integrated into GDB.
4629 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4631 DWARF 2's Call Frame Information makes available compiler generated
4632 information that more exactly describes the program's run-time stack.
4633 By using this information, GDB is able to provide more robust stack
4636 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4637 have been updated to use a new backtrace mechanism which includes
4638 DWARF 2 CFI support.
4642 GDB's remote protocol has been extended to include support for hosted
4643 file I/O (where the remote target uses GDB's file system). See GDB's
4644 remote protocol documentation for details.
4646 * All targets using the new architecture framework.
4648 All of GDB's targets have been updated to use the new internal
4649 architecture framework. The way is now open for future GDB releases
4650 to include cross-architecture native debugging support (i386 on amd64,
4653 * GNU/Linux's Thread Local Storage (TLS)
4655 GDB now includes support for for the GNU/Linux implementation of
4656 per-thread variables.
4658 * GNU/Linux's Native POSIX Thread Library (NPTL)
4660 GDB's thread code has been updated to work with either the new
4661 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4663 * Separate debug info.
4665 GDB, in conjunction with BINUTILS, now supports a mechanism for
4666 automatically loading debug information from a separate file. Instead
4667 of shipping full debug and non-debug versions of system libraries,
4668 system integrators can now instead ship just the stripped libraries
4669 and optional debug files.
4671 * DWARF 2 Location Expressions
4673 DWARF 2 Location Expressions allow the compiler to more completely
4674 describe the location of variables (even in optimized code) to the
4677 GDB now includes preliminary support for location expressions (support
4678 for DW_OP_piece is still missing).
4682 A number of long standing bugs that caused GDB to die while starting a
4683 Java application have been fixed. GDB's Java support is now
4684 considered "useable".
4686 * GNU/Linux support for fork, vfork, and exec.
4688 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4689 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4692 * GDB supports logging output to a file
4694 There are two new commands, "set logging" and "show logging", which can be
4695 used to capture GDB's output to a file.
4697 * The meaning of "detach" has changed for gdbserver
4699 The "detach" command will now resume the application, as documented. To
4700 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4703 * d10v, m68hc11 `regs' command deprecated
4705 The `info registers' command has been updated so that it displays the
4706 registers using a format identical to the old `regs' command.
4710 A new command, "maint set profile on/off", has been added. This command can
4711 be used to enable or disable profiling while running GDB, to profile a
4712 session or a set of commands. In addition there is a new configure switch,
4713 "--enable-profiling", which will cause GDB to be compiled with profiling
4714 data, for more informative profiling results.
4716 * Default MI syntax changed to "mi2".
4718 The default MI (machine interface) syntax, enabled by the command line
4719 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4720 "mi1", can be enabled by specifying the option "-i=mi1".
4722 Support for the original "mi0" syntax (included in GDB 5.0) has been
4725 Fix for gdb/192: removed extraneous space when displaying frame level.
4726 Fix for gdb/672: update changelist is now output in mi list format.
4727 Fix for gdb/702: a -var-assign that updates the value now shows up
4728 in a subsequent -var-update.
4730 * New native configurations.
4732 FreeBSD/amd64 x86_64-*-freebsd*
4734 * Multi-arched targets.
4736 HP/PA HPUX11 hppa*-*-hpux*
4737 Renesas M32R/D w/simulator m32r-*-elf*
4739 * OBSOLETE configurations and files
4741 Configurations that have been declared obsolete in this release have
4742 been commented out. Unless there is activity to revive these
4743 configurations, the next release of GDB will have their sources
4744 permanently REMOVED.
4746 Z8000 simulator z8k-zilog-none or z8ksim
4747 Matsushita MN10200 w/simulator mn10200-*-*
4748 H8/500 simulator h8500-hitachi-hms or h8500hms
4749 HP/PA running BSD hppa*-*-bsd*
4750 HP/PA running OSF/1 hppa*-*-osf*
4751 HP/PA Pro target hppa*-*-pro*
4752 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4753 Sequent family i[3456]86-sequent-sysv4*
4754 i[3456]86-sequent-sysv*
4755 i[3456]86-sequent-bsd*
4756 Tsqware Sparclet sparclet-*-*
4757 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4759 * REMOVED configurations and files
4762 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4763 IBM AIX PS/2 i[3456]86-*-aix
4764 i386 running Mach 3.0 i[3456]86-*-mach3*
4765 i386 running Mach i[3456]86-*-mach*
4766 i386 running OSF/1 i[3456]86-*osf1mk*
4767 HP/Apollo 68k Family m68*-apollo*-sysv*,
4769 m68*-hp-bsd*, m68*-hp-hpux*
4770 Argonaut Risc Chip (ARC) arc-*-*
4771 Mitsubishi D30V d30v-*-*
4772 Fujitsu FR30 fr30-*-elf*
4773 OS/9000 i[34]86-*-os9k
4774 I960 with MON960 i960-*-coff
4776 * MIPS $fp behavior changed
4778 The convenience variable $fp, for the MIPS, now consistently returns
4779 the address of the current frame's base. Previously, depending on the
4780 context, $fp could refer to either $sp or the current frame's base
4781 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4782 The GNU Source-Level Debugger''.
4784 *** Changes in GDB 5.3:
4786 * GNU/Linux shared library multi-threaded performance improved.
4788 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4789 `/proc', in preference to `ptrace' for memory reads. This may result
4790 in an improvement in the start-up time of multi-threaded, shared
4791 library applications when run under GDB. One GDB user writes: ``loads
4792 shared libs like mad''.
4794 * ``gdbserver'' now supports multi-threaded applications on some targets
4796 Support for debugging multi-threaded applications which use
4797 the GNU/Linux LinuxThreads package has been added for
4798 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4799 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4801 * GDB now supports C/C++ preprocessor macros.
4803 GDB now expands preprocessor macro invocations in C/C++ expressions,
4804 and provides various commands for showing macro definitions and how
4807 The new command `macro expand EXPRESSION' expands any macro
4808 invocations in expression, and shows the result.
4810 The new command `show macro MACRO-NAME' shows the definition of the
4811 macro named MACRO-NAME, and where it was defined.
4813 Most compilers don't include information about macros in the debugging
4814 information by default. In GCC 3.1, for example, you need to compile
4815 your program with the options `-gdwarf-2 -g3'. If the macro
4816 information is present in the executable, GDB will read it.
4818 * Multi-arched targets.
4820 DEC Alpha (partial) alpha*-*-*
4821 DEC VAX (partial) vax-*-*
4823 National Semiconductor NS32000 (partial) ns32k-*-*
4824 Motorola 68000 (partial) m68k-*-*
4825 Motorola MCORE mcore-*-*
4829 Fujitsu FRV architecture added by Red Hat frv*-*-*
4832 * New native configurations
4834 Alpha NetBSD alpha*-*-netbsd*
4835 SH NetBSD sh*-*-netbsdelf*
4836 MIPS NetBSD mips*-*-netbsd*
4837 UltraSPARC NetBSD sparc64-*-netbsd*
4839 * OBSOLETE configurations and files
4841 Configurations that have been declared obsolete in this release have
4842 been commented out. Unless there is activity to revive these
4843 configurations, the next release of GDB will have their sources
4844 permanently REMOVED.
4846 Mitsubishi D30V d30v-*-*
4847 OS/9000 i[34]86-*-os9k
4848 IBM AIX PS/2 i[3456]86-*-aix
4849 Fujitsu FR30 fr30-*-elf*
4850 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4851 Argonaut Risc Chip (ARC) arc-*-*
4852 i386 running Mach 3.0 i[3456]86-*-mach3*
4853 i386 running Mach i[3456]86-*-mach*
4854 i386 running OSF/1 i[3456]86-*osf1mk*
4855 HP/Apollo 68k Family m68*-apollo*-sysv*,
4857 m68*-hp-bsd*, m68*-hp-hpux*
4858 I960 with MON960 i960-*-coff
4860 * OBSOLETE languages
4862 CHILL, a Pascal like language used by telecommunications companies.
4864 * REMOVED configurations and files
4866 AMD 29k family via UDI a29k-amd-udi, udi29k
4867 A29K VxWorks a29k-*-vxworks
4868 AMD 29000 embedded, using EBMON a29k-none-none
4869 AMD 29000 embedded with COFF a29k-none-coff
4870 AMD 29000 embedded with a.out a29k-none-aout
4872 testsuite/gdb.hp/gdb.threads-hp/ directory
4874 * New command "set max-user-call-depth <nnn>"
4876 This command allows the user to limit the call depth of user-defined
4877 commands. The default is 1024.
4879 * Changes in FreeBSD/i386 native debugging.
4881 Support for the "generate-core-file" has been added.
4883 * New commands "dump", "append", and "restore".
4885 These commands allow data to be copied from target memory
4886 to a bfd-format or binary file (dump and append), and back
4887 from a file into memory (restore).
4889 * Improved "next/step" support on multi-processor Alpha Tru64.
4891 The previous single-step mechanism could cause unpredictable problems,
4892 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4893 of a software single-step mechanism prevents this.
4895 *** Changes in GDB 5.2.1:
4903 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4904 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4905 Fix, by Joel Brobecker imported from mainline.
4907 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4908 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4909 Fix, by Fred Fish, imported from mainline.
4911 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4912 Surprisingly enough, it works now.
4913 By Michal Ludvig, imported from mainline.
4915 i386 hardware watchpoint support:
4916 avoid misses on second run for some targets.
4917 By Pierre Muller, imported from mainline.
4919 *** Changes in GDB 5.2:
4921 * New command "set trust-readonly-sections on[off]".
4923 This command is a hint that tells gdb that read-only sections
4924 really are read-only (ie. that their contents will not change).
4925 In this mode, gdb will go to the object file rather than the
4926 target to read memory from read-only sections (such as ".text").
4927 This can be a significant performance improvement on some
4928 (notably embedded) targets.
4930 * New command "generate-core-file" (or "gcore").
4932 This new gdb command allows the user to drop a core file of the child
4933 process state at any time. So far it's been implemented only for
4934 GNU/Linux and Solaris, but should be relatively easily ported to other
4935 hosts. Argument is core file name (defaults to core.<pid>).
4937 * New command line option
4939 GDB now accepts --pid or -p followed by a process id.
4941 * Change in command line behavior -- corefiles vs. process ids.
4943 There is a subtle behavior in the way in which GDB handles
4944 command line arguments. The first non-flag argument is always
4945 a program to debug, but the second non-flag argument may either
4946 be a corefile or a process id. Previously, GDB would attempt to
4947 open the second argument as a corefile, and if that failed, would
4948 issue a superfluous error message and then attempt to attach it as
4949 a process. Now, if the second argument begins with a non-digit,
4950 it will be treated as a corefile. If it begins with a digit,
4951 GDB will attempt to attach it as a process, and if no such process
4952 is found, will then attempt to open it as a corefile.
4954 * Changes in ARM configurations.
4956 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4957 configuration is fully multi-arch.
4959 * New native configurations
4961 ARM NetBSD arm*-*-netbsd*
4962 x86 OpenBSD i[3456]86-*-openbsd*
4963 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4964 Sparc64 running FreeBSD sparc64-*-freebsd*
4968 Sanyo XStormy16 xstormy16-elf
4970 * OBSOLETE configurations and files
4972 Configurations that have been declared obsolete in this release have
4973 been commented out. Unless there is activity to revive these
4974 configurations, the next release of GDB will have their sources
4975 permanently REMOVED.
4977 AMD 29k family via UDI a29k-amd-udi, udi29k
4978 A29K VxWorks a29k-*-vxworks
4979 AMD 29000 embedded, using EBMON a29k-none-none
4980 AMD 29000 embedded with COFF a29k-none-coff
4981 AMD 29000 embedded with a.out a29k-none-aout
4983 testsuite/gdb.hp/gdb.threads-hp/ directory
4985 * REMOVED configurations and files
4987 TI TMS320C80 tic80-*-*
4989 PowerPC Solaris powerpcle-*-solaris*
4990 PowerPC Windows NT powerpcle-*-cygwin32
4991 PowerPC Netware powerpc-*-netware*
4992 Harris/CXUX m88k m88*-harris-cxux*
4993 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4994 ns32k-utek-sysv* ns32k-utek-*
4995 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4996 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4997 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4998 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4999 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
5001 * Changes to command line processing
5003 The new `--args' feature can be used to specify command-line arguments
5004 for the inferior from gdb's command line.
5006 * Changes to key bindings
5008 There is a new `operate-and-get-next' function bound to `C-o'.
5010 *** Changes in GDB 5.1.1
5012 Fix compile problem on DJGPP.
5014 Fix a problem with floating-point registers on the i386 being
5017 Fix to stop GDB crashing on .debug_str debug info.
5019 Numerous documentation fixes.
5021 Numerous testsuite fixes.
5023 *** Changes in GDB 5.1:
5025 * New native configurations
5027 Alpha FreeBSD alpha*-*-freebsd*
5028 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
5029 MIPS GNU/Linux mips*-*-linux*
5030 MIPS SGI Irix 6.x mips*-sgi-irix6*
5031 ia64 AIX ia64-*-aix*
5032 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
5036 Motorola 68HC11 and 68HC12 m68hc11-elf
5038 UltraSparc running GNU/Linux sparc64-*-linux*
5040 * OBSOLETE configurations and files
5042 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
5043 Harris/CXUX m88k m88*-harris-cxux*
5044 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5045 ns32k-utek-sysv* ns32k-utek-*
5046 TI TMS320C80 tic80-*-*
5048 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5049 PowerPC Solaris powerpcle-*-solaris*
5050 PowerPC Windows NT powerpcle-*-cygwin32
5051 PowerPC Netware powerpc-*-netware*
5052 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5053 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5054 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5055 Apple Macintosh (MPW) host N/A
5057 stuff.c (Program to stuff files into a specially prepared space in kdb)
5058 kdb-start.c (Main loop for the standalone kernel debugger)
5060 Configurations that have been declared obsolete in this release have
5061 been commented out. Unless there is activity to revive these
5062 configurations, the next release of GDB will have their sources
5063 permanently REMOVED.
5065 * REMOVED configurations and files
5067 Altos 3068 m68*-altos-*
5068 Convex c1-*-*, c2-*-*
5070 ARM RISCix arm-*-* (as host)
5074 * GDB has been converted to ISO C.
5076 GDB's source code has been converted to ISO C. In particular, the
5077 sources are fully protoized, and rely on standard headers being
5082 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
5084 * The MI enabled by default.
5086 The new machine oriented interface (MI) introduced in GDB 5.0 has been
5087 revised and enabled by default. Packages which use GDB as a debugging
5088 engine behind a UI or another front end are encouraged to switch to
5089 using the GDB/MI interface, instead of the old annotations interface
5090 which is now deprecated.
5092 * Support for debugging Pascal programs.
5094 GDB now includes support for debugging Pascal programs. The following
5095 main features are supported:
5097 - Pascal-specific data types such as sets;
5099 - automatic recognition of Pascal sources based on file-name
5102 - Pascal-style display of data types, variables, and functions;
5104 - a Pascal expression parser.
5106 However, some important features are not yet supported.
5108 - Pascal string operations are not supported at all;
5110 - there are some problems with boolean types;
5112 - Pascal type hexadecimal constants are not supported
5113 because they conflict with the internal variables format;
5115 - support for Pascal objects and classes is not full yet;
5117 - unlike Pascal, GDB is case-sensitive for symbol names.
5119 * Changes in completion.
5121 Commands such as `shell', `run' and `set args', which pass arguments
5122 to inferior programs, now complete on file names, similar to what
5123 users expect at the shell prompt.
5125 Commands which accept locations, such as `disassemble', `print',
5126 `breakpoint', `until', etc. now complete on filenames as well as
5127 program symbols. Thus, if you type "break foob TAB", and the source
5128 files linked into the programs include `foobar.c', that file name will
5129 be one of the candidates for completion. However, file names are not
5130 considered for completion after you typed a colon that delimits a file
5131 name from a name of a function in that file, as in "break foo.c:bar".
5133 `set demangle-style' completes on available demangling styles.
5135 * New platform-independent commands:
5137 It is now possible to define a post-hook for a command as well as a
5138 hook that runs before the command. For more details, see the
5139 documentation of `hookpost' in the GDB manual.
5141 * Changes in GNU/Linux native debugging.
5143 Support for debugging multi-threaded programs has been completely
5144 revised for all platforms except m68k and sparc. You can now debug as
5145 many threads as your system allows you to have.
5147 Attach/detach is supported for multi-threaded programs.
5149 Support for SSE registers was added for x86. This doesn't work for
5150 multi-threaded programs though.
5152 * Changes in MIPS configurations.
5154 Multi-arch support is enabled for all MIPS configurations.
5156 GDB can now be built as native debugger on SGI Irix 6.x systems for
5157 debugging n32 executables. (Debugging 64-bit executables is not yet
5160 * Unified support for hardware watchpoints in all x86 configurations.
5162 Most (if not all) native x86 configurations support hardware-assisted
5163 breakpoints and watchpoints in a unified manner. This support
5164 implements debug register sharing between watchpoints, which allows to
5165 put a virtually infinite number of watchpoints on the same address,
5166 and also supports watching regions up to 16 bytes with several debug
5169 The new maintenance command `maintenance show-debug-regs' toggles
5170 debugging print-outs in functions that insert, remove, and test
5171 watchpoints and hardware breakpoints.
5173 * Changes in the DJGPP native configuration.
5175 New command ``info dos sysinfo'' displays assorted information about
5176 the CPU, OS, memory, and DPMI server.
5178 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
5179 display information about segment descriptors stored in GDT, LDT, and
5182 New commands ``info dos pde'' and ``info dos pte'' display entries
5183 from Page Directory and Page Tables (for now works with CWSDPMI only).
5184 New command ``info dos address-pte'' displays the Page Table entry for
5185 a given linear address.
5187 GDB can now pass command lines longer than 126 characters to the
5188 program being debugged (requires an update to the libdbg.a library
5189 which is part of the DJGPP development kit).
5191 DWARF2 debug info is now supported.
5193 It is now possible to `step' and `next' through calls to `longjmp'.
5195 * Changes in documentation.
5197 All GDB documentation was converted to GFDL, the GNU Free
5198 Documentation License.
5200 Tracepoints-related commands are now fully documented in the GDB
5203 TUI, the Text-mode User Interface, is now documented in the manual.
5205 Tracepoints-related commands are now fully documented in the GDB
5208 The "GDB Internals" manual now has an index. It also includes
5209 documentation of `ui_out' functions, GDB coding standards, x86
5210 hardware watchpoints, and memory region attributes.
5212 * GDB's version number moved to ``version.in''
5214 The Makefile variable VERSION has been replaced by the file
5215 ``version.in''. People creating GDB distributions should update the
5216 contents of this file.
5220 GUD support is now a standard part of the EMACS distribution.
5222 *** Changes in GDB 5.0:
5224 * Improved support for debugging FP programs on x86 targets
5226 Unified and much-improved support for debugging floating-point
5227 programs on all x86 targets. In particular, ``info float'' now
5228 displays the FP registers in the same format on all x86 targets, with
5229 greater level of detail.
5231 * Improvements and bugfixes in hardware-assisted watchpoints
5233 It is now possible to watch array elements, struct members, and
5234 bitfields with hardware-assisted watchpoints. Data-read watchpoints
5235 on x86 targets no longer erroneously trigger when the address is
5238 * Improvements in the native DJGPP version of GDB
5240 The distribution now includes all the scripts and auxiliary files
5241 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5242 machines ``out of the box''.
5244 The DJGPP version can now debug programs that use signals. It is
5245 possible to catch signals that happened in the debuggee, deliver
5246 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5247 would kill the program being debugged.) Programs that hook hardware
5248 interrupts (keyboard, timer, etc.) can also be debugged.
5250 It is now possible to debug DJGPP programs that redirect their
5251 standard handles or switch them to raw (as opposed to cooked) mode, or
5252 even close them. The command ``run < foo > bar'' works as expected,
5253 and ``info terminal'' reports useful information about the debuggee's
5254 terminal, including raw/cooked mode, redirection, etc.
5256 The DJGPP version now uses termios functions for console I/O, which
5257 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5260 DOS-style file names with drive letters are now fully supported by
5263 It is now possible to debug DJGPP programs that switch their working
5264 directory. It is also possible to rerun the debuggee any number of
5265 times without restarting GDB; thus, you can use the same setup,
5266 breakpoints, etc. for many debugging sessions.
5268 * New native configurations
5270 ARM GNU/Linux arm*-*-linux*
5271 PowerPC GNU/Linux powerpc-*-linux*
5275 Motorola MCore mcore-*-*
5276 x86 VxWorks i[3456]86-*-vxworks*
5277 PowerPC VxWorks powerpc-*-vxworks*
5278 TI TMS320C80 tic80-*-*
5280 * OBSOLETE configurations
5282 Altos 3068 m68*-altos-*
5283 Convex c1-*-*, c2-*-*
5285 ARM RISCix arm-*-* (as host)
5288 Configurations that have been declared obsolete will be commented out,
5289 but the code will be left in place. If there is no activity to revive
5290 these configurations before the next release of GDB, the sources will
5291 be permanently REMOVED.
5293 * Gould support removed
5295 Support for the Gould PowerNode and NP1 has been removed.
5297 * New features for SVR4
5299 On SVR4 native platforms (such as Solaris), if you attach to a process
5300 without first loading a symbol file, GDB will now attempt to locate and
5301 load symbols from the running process's executable file.
5303 * Many C++ enhancements
5305 C++ support has been greatly improved. Overload resolution now works properly
5306 in almost all cases. RTTI support is on the way.
5308 * Remote targets can connect to a sub-program
5310 A popen(3) style serial-device has been added. This device starts a
5311 sub-process (such as a stand-alone simulator) and then communicates
5312 with that. The sub-program to run is specified using the syntax
5313 ``|<program> <args>'' vis:
5315 (gdb) set remotedebug 1
5316 (gdb) target extended-remote |mn10300-elf-sim program-args
5318 * MIPS 64 remote protocol
5320 A long standing bug in the mips64 remote protocol where by GDB
5321 expected certain 32 bit registers (ex SR) to be transfered as 32
5322 instead of 64 bits has been fixed.
5324 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5325 added to provide backward compatibility with older versions of GDB.
5327 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5329 The command ``set remotebinarydownload'' command has been replaced by
5330 ``set remote X-packet''. Other commands in ``set remote'' family
5331 include ``set remote P-packet''.
5333 * Breakpoint commands accept ranges.
5335 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5336 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5337 ``tracepoint passcount'' also accepts a range of tracepoints.
5339 * ``apropos'' command added.
5341 The ``apropos'' command searches through command names and
5342 documentation strings, printing out matches, making it much easier to
5343 try to find a command that does what you are looking for.
5347 A new machine oriented interface (MI) has been added to GDB. This
5348 interface is designed for debug environments running GDB as a separate
5349 process. This is part of the long term libGDB project. See the
5350 "GDB/MI" chapter of the GDB manual for further information. It can be
5351 enabled by configuring with:
5353 .../configure --enable-gdbmi
5355 *** Changes in GDB-4.18:
5357 * New native configurations
5359 HP-UX 10.20 hppa*-*-hpux10.20
5360 HP-UX 11.x hppa*-*-hpux11.0*
5361 M68K GNU/Linux m68*-*-linux*
5365 Fujitsu FR30 fr30-*-elf*
5366 Intel StrongARM strongarm-*-*
5367 Mitsubishi D30V d30v-*-*
5369 * OBSOLETE configurations
5371 Gould PowerNode, NP1 np1-*-*, pn-*-*
5373 Configurations that have been declared obsolete will be commented out,
5374 but the code will be left in place. If there is no activity to revive
5375 these configurations before the next release of GDB, the sources will
5376 be permanently REMOVED.
5380 As a compatibility experiment, GDB's source files buildsym.h and
5381 buildsym.c have been converted to pure standard C, no longer
5382 containing any K&R compatibility code. We believe that all systems in
5383 use today either come with a standard C compiler, or have a GCC port
5384 available. If this is not true, please report the affected
5385 configuration to bug-gdb@gnu.org immediately. See the README file for
5386 information about getting a standard C compiler if you don't have one
5391 GDB now uses readline 2.2.
5393 * set extension-language
5395 You can now control the mapping between filename extensions and source
5396 languages by using the `set extension-language' command. For instance,
5397 you can ask GDB to treat .c files as C++ by saying
5398 set extension-language .c c++
5399 The command `info extensions' lists all of the recognized extensions
5400 and their associated languages.
5402 * Setting processor type for PowerPC and RS/6000
5404 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5405 you can use the `set processor' command to specify what variant of the
5406 PowerPC family you are debugging. The command
5410 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5411 following PowerPC and RS6000 variants:
5413 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5414 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5416 403GC IBM PowerPC 403GC
5417 505 Motorola PowerPC 505
5418 860 Motorola PowerPC 860 or 850
5419 601 Motorola PowerPC 601
5420 602 Motorola PowerPC 602
5421 603 Motorola/IBM PowerPC 603 or 603e
5422 604 Motorola PowerPC 604 or 604e
5423 750 Motorola/IBM PowerPC 750 or 750
5425 At the moment, this command just tells GDB what to name the
5426 special-purpose processor registers. Since almost all the affected
5427 registers are inaccessible to user-level programs, this command is
5428 only useful for remote debugging in its present form.
5432 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5433 more extensive support for HP-UX. Added features include shared
5434 library support, kernel threads and hardware watchpoints for 11.00,
5435 support for HP's ANSI C and C++ compilers, and a compatibility mode
5436 for xdb and dbx commands.
5440 HP's donation includes the new concept of catchpoints, which is a
5441 generalization of the old catch command. On HP-UX, it is now possible
5442 to catch exec, fork, and vfork, as well as library loading.
5444 This means that the existing catch command has changed; its first
5445 argument now specifies the type of catch to be set up. See the
5446 output of "help catch" for a list of catchpoint types.
5448 * Debugging across forks
5450 On HP-UX, you can choose which process to debug when a fork() happens
5455 HP has donated a curses-based terminal user interface (TUI). To get
5456 it, build with --enable-tui. Although this can be enabled for any
5457 configuration, at present it only works for native HP debugging.
5459 * GDB remote protocol additions
5461 A new protocol packet 'X' that writes binary data is now available.
5462 Default behavior is to try 'X', then drop back to 'M' if the stub
5463 fails to respond. The settable variable `remotebinarydownload'
5464 allows explicit control over the use of 'X'.
5466 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5467 full 64-bit address. The command
5469 set remoteaddresssize 32
5471 can be used to revert to the old behaviour. For existing remote stubs
5472 the change should not be noticed, as the additional address information
5475 In order to assist in debugging stubs, you may use the maintenance
5476 command `packet' to send any text string to the stub. For instance,
5478 maint packet heythere
5480 sends the packet "$heythere#<checksum>". Note that it is very easy to
5481 disrupt a debugging session by sending the wrong packet at the wrong
5484 The compare-sections command allows you to compare section data on the
5485 target to what is in the executable file without uploading or
5486 downloading, by comparing CRC checksums.
5488 * Tracing can collect general expressions
5490 You may now collect general expressions at tracepoints. This requires
5491 further additions to the target-side stub; see tracepoint.c and
5492 doc/agentexpr.texi for further details.
5494 * mask-address variable for Mips
5496 For Mips targets, you may control the zeroing of the upper 32 bits of
5497 a 64-bit address by entering `set mask-address on'. This is mainly
5498 of interest to users of embedded R4xxx and R5xxx processors.
5500 * Higher serial baud rates
5502 GDB's serial code now allows you to specify baud rates 57600, 115200,
5503 230400, and 460800 baud. (Note that your host system may not be able
5504 to achieve all of these rates.)
5508 The i960 configuration now includes an initial implementation of a
5509 builtin simulator, contributed by Jim Wilson.
5512 *** Changes in GDB-4.17:
5514 * New native configurations
5516 Alpha GNU/Linux alpha*-*-linux*
5517 Unixware 2.x i[3456]86-unixware2*
5518 Irix 6.x mips*-sgi-irix6*
5519 PowerPC GNU/Linux powerpc-*-linux*
5520 PowerPC Solaris powerpcle-*-solaris*
5521 Sparc GNU/Linux sparc-*-linux*
5522 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5526 Argonaut Risc Chip (ARC) arc-*-*
5527 Hitachi H8/300S h8300*-*-*
5528 Matsushita MN10200 w/simulator mn10200-*-*
5529 Matsushita MN10300 w/simulator mn10300-*-*
5530 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5531 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5532 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5533 Mitsubishi D10V w/simulator d10v-*-*
5534 Mitsubishi M32R/D w/simulator m32r-*-elf*
5535 Tsqware Sparclet sparclet-*-*
5536 NEC V850 w/simulator v850-*-*
5538 * New debugging protocols
5540 ARM with RDI protocol arm*-*-*
5541 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5542 DDB and LSI variants of PMON protocol mips*-*-*
5543 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5544 PowerPC with SDS protocol powerpc{,le}-*-eabi
5545 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5549 All configurations can now understand and use the DWARF 2 debugging
5550 format. The choice is automatic, if the symbol file contains DWARF 2
5555 GDB now includes basic Java language support. This support is
5556 only useful with Java compilers that produce native machine code.
5558 * solib-absolute-prefix and solib-search-path
5560 For SunOS and SVR4 shared libraries, you may now set the prefix for
5561 loading absolute shared library symbol files, and the search path for
5562 locating non-absolute shared library symbol files.
5564 * Live range splitting
5566 GDB can now effectively debug code for which GCC has performed live
5567 range splitting as part of its optimization. See gdb/doc/LRS for
5568 more details on the expected format of the stabs information.
5572 GDB's support for the GNU Hurd, including thread debugging, has been
5573 updated to work with current versions of the Hurd.
5577 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5578 instruction set. ARM GDB automatically detects when Thumb
5579 instructions are in use, and adjusts disassembly and backtracing
5584 GDB's MIPS target configurations now handle the MIP16 16-bit
5589 GDB now includes support for overlays; if an executable has been
5590 linked such that multiple sections are based at the same address, GDB
5591 will decide which section to use for symbolic info. You can choose to
5592 control the decision manually, using overlay commands, or implement
5593 additional target-side support and use "overlay load-target" to bring
5594 in the overlay mapping. Do "help overlay" for more detail.
5598 The command "info symbol <address>" displays information about
5599 the symbol at the specified address.
5603 The standard remote protocol now includes an extension that allows
5604 asynchronous collection and display of trace data. This requires
5605 extensive support in the target-side debugging stub. Tracing mode
5606 includes a new interaction mode in GDB and new commands: see the
5607 file tracepoint.c for more details.
5611 Configurations for embedded MIPS now include a simulator contributed
5612 by Cygnus Solutions. The simulator supports the instruction sets
5613 of most MIPS variants.
5617 Sparc configurations may now include the ERC32 simulator contributed
5618 by the European Space Agency. The simulator is not built into
5619 Sparc targets by default; configure with --enable-sim to include it.
5623 For target configurations that may include multiple variants of a
5624 basic architecture (such as MIPS and SH), you may now set the
5625 architecture explicitly. "set arch" sets, "info arch" lists
5626 the possible architectures.
5628 *** Changes in GDB-4.16:
5630 * New native configurations
5632 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5633 M68K NetBSD m68k-*-netbsd*
5634 PowerPC AIX 4.x powerpc-*-aix*
5635 PowerPC MacOS powerpc-*-macos*
5636 PowerPC Windows NT powerpcle-*-cygwin32
5637 RS/6000 AIX 4.x rs6000-*-aix4*
5641 ARM with RDP protocol arm-*-*
5642 I960 with MON960 i960-*-coff
5643 MIPS VxWorks mips*-*-vxworks*
5644 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5645 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5647 Matra Sparclet sparclet-*-*
5651 The powerpc-eabi configuration now includes the PSIM simulator,
5652 contributed by Andrew Cagney, with assistance from Mike Meissner.
5653 PSIM is a very elaborate model of the PowerPC, including not only
5654 basic instruction set execution, but also details of execution unit
5655 performance and I/O hardware. See sim/ppc/README for more details.
5659 GDB now works with Solaris 2.5.
5661 * Windows 95/NT native
5663 GDB will now work as a native debugger on Windows 95 and Windows NT.
5664 To build it from source, you must use the "gnu-win32" environment,
5665 which uses a DLL to emulate enough of Unix to run the GNU tools.
5666 Further information, binaries, and sources are available at
5667 ftp.cygnus.com, under pub/gnu-win32.
5669 * dont-repeat command
5671 If a user-defined command includes the command `dont-repeat', then the
5672 command will not be repeated if the user just types return. This is
5673 useful if the command is time-consuming to run, so that accidental
5674 extra keystrokes don't run the same command many times.
5676 * Send break instead of ^C
5678 The standard remote protocol now includes an option to send a break
5679 rather than a ^C to the target in order to interrupt it. By default,
5680 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5682 * Remote protocol timeout
5684 The standard remote protocol includes a new variable `remotetimeout'
5685 that allows you to set the number of seconds before GDB gives up trying
5686 to read from the target. The default value is 2.
5688 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5690 By default GDB will automatically keep track of objects as they are
5691 loaded and unloaded by the dynamic linker. By using the command `set
5692 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5693 when shared library events occur, thus allowing you to set breakpoints
5694 in shared libraries which are explicitly loaded by the inferior.
5696 Note this feature does not work on hpux8. On hpux9 you must link
5697 /usr/lib/end.o into your program. This feature should work
5698 automatically on hpux10.
5700 * Irix 5.x hardware watchpoint support
5702 Irix 5 configurations now support the use of hardware watchpoints.
5704 * Mips protocol "SYN garbage limit"
5706 When debugging a Mips target using the `target mips' protocol, you
5707 may set the number of characters that GDB will ignore by setting
5708 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5709 every character. The default value is 1050.
5711 * Recording and replaying remote debug sessions
5713 If you set `remotelogfile' to the name of a file, gdb will write to it
5714 a recording of a remote debug session. This recording may then be
5715 replayed back to gdb using "gdbreplay". See gdbserver/README for
5716 details. This is useful when you have a problem with GDB while doing
5717 remote debugging; you can make a recording of the session and send it
5718 to someone else, who can then recreate the problem.
5720 * Speedups for remote debugging
5722 GDB includes speedups for downloading and stepping MIPS systems using
5723 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5724 and more efficient S-record downloading.
5726 * Memory use reductions and statistics collection
5728 GDB now uses less memory and reports statistics about memory usage.
5729 Try the `maint print statistics' command, for example.
5731 *** Changes in GDB-4.15:
5733 * Psymtabs for XCOFF
5735 The symbol reader for AIX GDB now uses partial symbol tables. This
5736 can greatly improve startup time, especially for large executables.
5738 * Remote targets use caching
5740 Remote targets now use a data cache to speed up communication with the
5741 remote side. The data cache could lead to incorrect results because
5742 it doesn't know about volatile variables, thus making it impossible to
5743 debug targets which use memory mapped I/O devices. `set remotecache
5744 off' turns the the data cache off.
5746 * Remote targets may have threads
5748 The standard remote protocol now includes support for multiple threads
5749 in the target system, using new protocol commands 'H' and 'T'. See
5750 gdb/remote.c for details.
5754 If GDB is configured with `--enable-netrom', then it will include
5755 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5756 acts as though it is a bank of ROM on the target board, but you can
5757 write into it over the network. GDB's support consists only of
5758 support for fast loading into the emulated ROM; to debug, you must use
5759 another protocol, such as standard remote protocol. The usual
5760 sequence is something like
5762 target nrom <netrom-hostname>
5764 target remote <netrom-hostname>:1235
5768 GDB now includes support for the Apple Macintosh, as a host only. It
5769 may be run as either an MPW tool or as a standalone application, and
5770 it can debug through the serial port. All the usual GDB commands are
5771 available, but to the target command, you must supply "serial" as the
5772 device type instead of "/dev/ttyXX". See mpw-README in the main
5773 directory for more information on how to build. The MPW configuration
5774 scripts */mpw-config.in support only a few targets, and only the
5775 mips-idt-ecoff target has been tested.
5779 GDB configuration now uses autoconf. This is not user-visible,
5780 but does simplify configuration and building.
5784 GDB now supports hpux10.
5786 *** Changes in GDB-4.14:
5788 * New native configurations
5790 x86 FreeBSD i[345]86-*-freebsd
5791 x86 NetBSD i[345]86-*-netbsd
5792 NS32k NetBSD ns32k-*-netbsd
5793 Sparc NetBSD sparc-*-netbsd
5797 A29K VxWorks a29k-*-vxworks
5798 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5799 CPU32 EST-300 emulator m68*-*-est*
5800 PowerPC ELF powerpc-*-elf
5803 * Alpha OSF/1 support for procfs
5805 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5806 possible to attach to running processes. As the mounting of the /proc
5807 filesystem is optional on the Alpha, GDB automatically determines
5808 the availability of /proc during startup. This can lead to problems
5809 if /proc is unmounted after GDB has been started.
5811 * Arguments to user-defined commands
5813 User commands may accept up to 10 arguments separated by whitespace.
5814 Arguments are accessed within the user command via $arg0..$arg9. A
5817 print $arg0 + $arg1 + $arg2
5819 To execute the command use:
5822 Defines the command "adder" which prints the sum of its three arguments.
5823 Note the arguments are text substitutions, so they may reference variables,
5824 use complex expressions, or even perform inferior function calls.
5826 * New `if' and `while' commands
5828 This makes it possible to write more sophisticated user-defined
5829 commands. Both commands take a single argument, which is the
5830 expression to evaluate, and must be followed by the commands to
5831 execute, one per line, if the expression is nonzero, the list being
5832 terminated by the word `end'. The `if' command list may include an
5833 `else' word, which causes the following commands to be executed only
5834 if the expression is zero.
5836 * Fortran source language mode
5838 GDB now includes partial support for Fortran 77. It will recognize
5839 Fortran programs and can evaluate a subset of Fortran expressions, but
5840 variables and functions may not be handled correctly. GDB will work
5841 with G77, but does not yet know much about symbols emitted by other
5844 * Better HPUX support
5846 Most debugging facilities now work on dynamic executables for HPPAs
5847 running hpux9 or later. You can attach to running dynamically linked
5848 processes, but by default the dynamic libraries will be read-only, so
5849 for instance you won't be able to put breakpoints in them. To change
5850 that behavior do the following before running the program:
5856 This will cause the libraries to be mapped private and read-write.
5857 To revert to the normal behavior, do this:
5863 You cannot set breakpoints or examine data in the library until after
5864 the library is loaded if the function/data symbols do not have
5867 GDB can now also read debug symbols produced by the HP C compiler on
5868 HPPAs (sorry, no C++, Fortran or 68k support).
5870 * Target byte order now dynamically selectable
5872 You can choose which byte order to use with a target system, via the
5873 commands "set endian big" and "set endian little", and you can see the
5874 current setting by using "show endian". You can also give the command
5875 "set endian auto", in which case GDB will use the byte order
5876 associated with the executable. Currently, only embedded MIPS
5877 configurations support dynamic selection of target byte order.
5879 * New DOS host serial code
5881 This version uses DPMI interrupts to handle buffered I/O, so you
5882 no longer need to run asynctsr when debugging boards connected to
5885 *** Changes in GDB-4.13:
5887 * New "complete" command
5889 This lists all the possible completions for the rest of the line, if it
5890 were to be given as a command itself. This is intended for use by emacs.
5892 * Trailing space optional in prompt
5894 "set prompt" no longer adds a space for you after the prompt you set. This
5895 allows you to set a prompt which ends in a space or one that does not.
5897 * Breakpoint hit counts
5899 "info break" now displays a count of the number of times the breakpoint
5900 has been hit. This is especially useful in conjunction with "ignore"; you
5901 can ignore a large number of breakpoint hits, look at the breakpoint info
5902 to see how many times the breakpoint was hit, then run again, ignoring one
5903 less than that number, and this will get you quickly to the last hit of
5906 * Ability to stop printing at NULL character
5908 "set print null-stop" will cause GDB to stop printing the characters of
5909 an array when the first NULL is encountered. This is useful when large
5910 arrays actually contain only short strings.
5912 * Shared library breakpoints
5914 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5915 breakpoints in shared libraries before the executable is run.
5917 * Hardware watchpoints
5919 There is a new hardware breakpoint for the watch command for sparclite
5920 targets. See gdb/sparclite/hw_breakpoint.note.
5922 Hardware watchpoints are also now supported under GNU/Linux.
5926 Annotations have been added. These are for use with graphical interfaces,
5927 and are still experimental. Currently only gdba.el uses these.
5929 * Improved Irix 5 support
5931 GDB now works properly with Irix 5.2.
5933 * Improved HPPA support
5935 GDB now works properly with the latest GCC and GAS.
5937 * New native configurations
5939 Sequent PTX4 i[34]86-sequent-ptx4
5940 HPPA running OSF/1 hppa*-*-osf*
5941 Atari TT running SVR4 m68*-*-sysv4*
5942 RS/6000 LynxOS rs6000-*-lynxos*
5946 OS/9000 i[34]86-*-os9k
5947 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5950 * Hitachi SH7000 and E7000-PC ICE support
5952 There is now support for communicating with the Hitachi E7000-PC ICE.
5953 This is available automatically when GDB is configured for the SH.
5957 As usual, a variety of small fixes and improvements, both generic
5958 and configuration-specific. See the ChangeLog for more detail.
5960 *** Changes in GDB-4.12:
5962 * Irix 5 is now supported
5966 GDB-4.12 on the HPPA has a number of changes which make it unable
5967 to debug the output from the currently released versions of GCC and
5968 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5969 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5970 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5973 *** Changes in GDB-4.11:
5975 * User visible changes:
5979 The "set remotedebug" option is now consistent between the mips remote
5980 target, remote targets using the gdb-specific protocol, UDI (AMD's
5981 debug protocol for the 29k) and the 88k bug monitor. It is now an
5982 integer specifying a debug level (normally 0 or 1, but 2 means more
5983 debugging info for the mips target).
5985 * DEC Alpha native support
5987 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5988 debug info, but GDB works fairly well with the DEC compiler and should
5989 work with a future GCC release. See the README file for a few
5990 Alpha-specific notes.
5992 * Preliminary thread implementation
5994 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5996 * LynxOS native and target support for 386
5998 This release has been hosted on LynxOS 2.2, and also can be configured
5999 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
6002 * Improvements in C++ mangling/demangling.
6004 This release has much better g++ debugging, specifically in name
6005 mangling/demangling, virtual function calls, print virtual table,
6006 call methods, ...etc.
6008 *** Changes in GDB-4.10:
6010 * User visible changes:
6012 Remote debugging using the GDB-specific (`target remote') protocol now
6013 supports the `load' command. This is only useful if you have some
6014 other way of getting the stub to the target system, and you can put it
6015 somewhere in memory where it won't get clobbered by the download.
6017 Filename completion now works.
6019 When run under emacs mode, the "info line" command now causes the
6020 arrow to point to the line specified. Also, "info line" prints
6021 addresses in symbolic form (as well as hex).
6023 All vxworks based targets now support a user settable option, called
6024 vxworks-timeout. This option represents the number of seconds gdb
6025 should wait for responses to rpc's. You might want to use this if
6026 your vxworks target is, perhaps, a slow software simulator or happens
6027 to be on the far side of a thin network line.
6031 This release contains support for using a DEC alpha as a GDB host for
6032 cross debugging. Native alpha debugging is not supported yet.
6035 *** Changes in GDB-4.9:
6039 This is the first GDB release which is accompanied by a matching testsuite.
6040 The testsuite requires installation of dejagnu, which should be available
6041 via ftp from most sites that carry GNU software.
6045 'Cfront' style demangling has had its name changed to 'ARM' style, to
6046 emphasize that it was written from the specifications in the C++ Annotated
6047 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
6048 disclaimers, it still generated too much confusion with users attempting to
6049 use gdb with AT&T cfront.
6053 GDB now uses a standard remote interface to a simulator library.
6054 So far, the library contains simulators for the Zilog Z8001/2, the
6055 Hitachi H8/300, H8/500 and Super-H.
6057 * New targets supported
6059 H8/300 simulator h8300-hitachi-hms or h8300hms
6060 H8/500 simulator h8500-hitachi-hms or h8500hms
6061 SH simulator sh-hitachi-hms or sh
6062 Z8000 simulator z8k-zilog-none or z8ksim
6063 IDT MIPS board over serial line mips-idt-ecoff
6065 Cross-debugging to GO32 targets is supported. It requires a custom
6066 version of the i386-stub.c module which is integrated with the
6067 GO32 memory extender.
6069 * New remote protocols
6071 MIPS remote debugging protocol.
6073 * New source languages supported
6075 This version includes preliminary support for Chill, a Pascal like language
6076 used by telecommunications companies. Chill support is also being integrated
6077 into the GNU compiler, but we don't know when it will be publically available.
6080 *** Changes in GDB-4.8:
6082 * HP Precision Architecture supported
6084 GDB now supports HP PA-RISC machines running HPUX. A preliminary
6085 version of this support was available as a set of patches from the
6086 University of Utah. GDB does not support debugging of programs
6087 compiled with the HP compiler, because HP will not document their file
6088 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
6089 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
6091 Many problems in the preliminary version have been fixed.
6093 * Faster and better demangling
6095 We have improved template demangling and fixed numerous bugs in the GNU style
6096 demangler. It can now handle type modifiers such as `static' or `const'. Wide
6097 character types (wchar_t) are now supported. Demangling of each symbol is now
6098 only done once, and is cached when the symbol table for a file is read in.
6099 This results in a small increase in memory usage for C programs, a moderate
6100 increase in memory usage for C++ programs, and a fantastic speedup in
6103 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
6104 from the specifications in the Annotated Reference Manual, which AT&T's
6105 compiler does not actually implement.
6107 * G++ multiple inheritance compiler problem
6109 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
6110 inheritance lattices was reworked to properly discover ambiguities. We
6111 recently found an example which causes this new algorithm to fail in a
6112 very subtle way, producing bad debug information for those classes.
6113 The file 'gcc.patch' (in this directory) can be applied to gcc to
6114 circumvent the problem. A future GCC release will contain a complete
6117 The previous G++ debug info problem (mentioned below for the gdb-4.7
6118 release) is fixed in gcc version 2.3.2.
6120 * Improved configure script
6122 The `configure' script will now attempt to guess your system type if
6123 you don't supply a host system type. The old scheme of supplying a
6124 host system triplet is preferable over using this. All the magic is
6125 done in the new `config.guess' script. Examine it for details.
6127 We have also brought our configure script much more in line with the FSF's
6128 version. It now supports the --with-xxx options. In particular,
6129 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
6130 The resulting GDB will not be able to read arbitrary object file formats --
6131 only the format ``expected'' to be used on the configured target system.
6132 We hope to make this the default in a future release.
6134 * Documentation improvements
6136 There's new internal documentation on how to modify GDB, and how to
6137 produce clean changes to the code. We implore people to read it
6138 before submitting changes.
6140 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
6141 M4 macros. The new texinfo.tex is provided in this release. Pre-built
6142 `info' files are also provided. To build `info' files from scratch,
6143 you will need the latest `makeinfo' release, which will be available in
6144 a future texinfo-X.Y release.
6146 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
6147 We're not sure exactly which versions have this problem, but it has
6148 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
6149 or better. If that isn't possible, there is a patch in
6150 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
6151 around this problem.
6155 GDB now supports array constants that can be used in expressions typed in by
6156 the user. The syntax is `{element, element, ...}'. Ie: you can now type
6157 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
6160 The new directory `gdb/sparclite' contains a program that demonstrates
6161 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
6163 * New native hosts supported
6165 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
6166 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
6168 * New targets supported
6170 AMD 29k family via UDI a29k-amd-udi or udi29k
6172 * New file formats supported
6174 BFD now supports reading HP/PA-RISC executables (SOM file format?),
6175 HPUX core files, and SCO 3.2v2 core files.
6179 Attaching to processes now works again; thanks for the many bug reports.
6181 We have also stomped on a bunch of core dumps caused by
6182 printf_filtered("%s") problems.
6184 We eliminated a copyright problem on the rpc and ptrace header files
6185 for VxWorks, which was discovered at the last minute during the 4.7
6186 release. You should now be able to build a VxWorks GDB.
6188 You can now interrupt gdb while an attached process is running. This
6189 will cause the attached process to stop, and give control back to GDB.
6191 We fixed problems caused by using too many file descriptors
6192 for reading symbols from object files and libraries. This was
6193 especially a problem for programs that used many (~100) shared
6196 The `step' command now only enters a subroutine if there is line number
6197 information for the subroutine. Otherwise it acts like the `next'
6198 command. Previously, `step' would enter subroutines if there was
6199 any debugging information about the routine. This avoids problems
6200 when using `cc -g1' on MIPS machines.
6202 * Internal improvements
6204 GDB's internal interfaces have been improved to make it easier to support
6205 debugging of multiple languages in the future.
6207 GDB now uses a common structure for symbol information internally.
6208 Minimal symbols (derived from linkage symbols in object files), partial
6209 symbols (from a quick scan of debug information), and full symbols
6210 contain a common subset of information, making it easier to write
6211 shared code that handles any of them.
6213 * New command line options
6215 We now accept --silent as an alias for --quiet.
6219 The memory-mapped-malloc library is now licensed under the GNU Library
6220 General Public License.
6222 *** Changes in GDB-4.7:
6224 * Host/native/target split
6226 GDB has had some major internal surgery to untangle the support for
6227 hosts and remote targets. Now, when you configure GDB for a remote
6228 target, it will no longer load in all of the support for debugging
6229 local programs on the host. When fully completed and tested, this will
6230 ensure that arbitrary host/target combinations are possible.
6232 The primary conceptual shift is to separate the non-portable code in
6233 GDB into three categories. Host specific code is required any time GDB
6234 is compiled on that host, regardless of the target. Target specific
6235 code relates to the peculiarities of the target, but can be compiled on
6236 any host. Native specific code is everything else: it can only be
6237 built when the host and target are the same system. Child process
6238 handling and core file support are two common `native' examples.
6240 GDB's use of /proc for controlling Unix child processes is now cleaner.
6241 It has been split out into a single module under the `target_ops' vector,
6242 plus two native-dependent functions for each system that uses /proc.
6244 * New hosts supported
6246 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6247 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6248 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6250 * New targets supported
6252 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6253 68030 and CPU32 m68030-*-*, m68332-*-*
6255 * New native hosts supported
6257 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6258 (386bsd is not well tested yet)
6259 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6261 * New file formats supported
6263 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6264 supports reading of `a.out.adobe' object files, which are an a.out
6265 format extended with minimal information about multiple sections.
6269 `show copying' is the same as the old `info copying'.
6270 `show warranty' is the same as `info warrantee'.
6271 These were renamed for consistency. The old commands continue to work.
6273 `info handle' is a new alias for `info signals'.
6275 You can now define pre-command hooks, which attach arbitrary command
6276 scripts to any command. The commands in the hook will be executed
6277 prior to the user's command. You can also create a hook which will be
6278 executed whenever the program stops. See gdb.texinfo.
6282 We now deal with Cfront style name mangling, and can even extract type
6283 info from mangled symbols. GDB can automatically figure out which
6284 symbol mangling style your C++ compiler uses.
6286 Calling of methods and virtual functions has been improved as well.
6290 The crash that occured when debugging Sun Ansi-C compiled binaries is
6291 fixed. This was due to mishandling of the extra N_SO stabs output
6294 We also finally got Ultrix 4.2 running in house, and fixed core file
6295 support, with help from a dozen people on the net.
6297 John M. Farrell discovered that the reason that single-stepping was so
6298 slow on all of the Mips based platforms (primarily SGI and DEC) was
6299 that we were trying to demangle and lookup a symbol used for internal
6300 purposes on every instruction that was being stepped through. Changing
6301 the name of that symbol so that it couldn't be mistaken for a C++
6302 mangled symbol sped things up a great deal.
6304 Rich Pixley sped up symbol lookups in general by getting much smarter
6305 about when C++ symbol mangling is necessary. This should make symbol
6306 completion (TAB on the command line) much faster. It's not as fast as
6307 we'd like, but it's significantly faster than gdb-4.6.
6311 A new user controllable variable 'call_scratch_address' can
6312 specify the location of a scratch area to be used when GDB
6313 calls a function in the target. This is necessary because the
6314 usual method of putting the scratch area on the stack does not work
6315 in systems that have separate instruction and data spaces.
6317 We integrated changes to support the 29k UDI (Universal Debugger
6318 Interface), but discovered at the last minute that we didn't have all
6319 of the appropriate copyright paperwork. We are working with AMD to
6320 resolve this, and hope to have it available soon.
6324 We have sped up the remote serial line protocol, especially for targets
6325 with lots of registers. It now supports a new `expedited status' ('T')
6326 message which can be used in place of the existing 'S' status message.
6327 This allows the remote stub to send only the registers that GDB
6328 needs to make a quick decision about single-stepping or conditional
6329 breakpoints, eliminating the need to fetch the entire register set for
6330 each instruction being stepped through.
6332 The GDB remote serial protocol now implements a write-through cache for
6333 registers, only re-reading the registers if the target has run.
6335 There is also a new remote serial stub for SPARC processors. You can
6336 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6337 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6338 processor with a serial port.
6342 Configure.in files have become much easier to read and modify. A new
6343 `table driven' format makes it more obvious what configurations are
6344 supported, and what files each one uses.
6348 There is a new opcodes library which will eventually contain all of the
6349 disassembly routines and opcode tables. At present, it only contains
6350 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6351 disassembler (binutils/objdump) to share these routines.
6353 The libiberty library is now copylefted under the GNU Library General
6354 Public License. This allows more liberal use, and was done so libg++
6355 can use it. This makes no difference to GDB, since the Library License
6356 grants all the rights from the General Public License.
6360 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6361 reference to the stabs symbol info used by the debugger. It is (as far
6362 as we know) the only published document on this fascinating topic. We
6363 encourage you to read it, compare it to the stabs information on your
6364 system, and send improvements on the document in general (to
6365 bug-gdb@prep.ai.mit.edu).
6367 And, of course, many bugs have been fixed.
6370 *** Changes in GDB-4.6:
6372 * Better support for C++ function names
6374 GDB now accepts as input the "demangled form" of C++ overloaded function
6375 names and member function names, and can do command completion on such names
6376 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6377 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6378 Make use of command completion, it is your friend.
6380 GDB also now accepts a variety of C++ mangled symbol formats. They are
6381 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6382 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6383 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6384 for the list of formats.
6386 * G++ symbol mangling problem
6388 Recent versions of gcc have a bug in how they emit debugging information for
6389 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6390 directory) can be applied to gcc to fix the problem. Alternatively, if you
6391 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6392 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6393 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6396 * New 'maintenance' command
6398 All of the commands related to hacking GDB internals have been moved out of
6399 the main command set, and now live behind the 'maintenance' command. This
6400 can also be abbreviated as 'mt'. The following changes were made:
6402 dump-me -> maintenance dump-me
6403 info all-breakpoints -> maintenance info breakpoints
6404 printmsyms -> maintenance print msyms
6405 printobjfiles -> maintenance print objfiles
6406 printpsyms -> maintenance print psymbols
6407 printsyms -> maintenance print symbols
6409 The following commands are new:
6411 maintenance demangle Call internal GDB demangler routine to
6412 demangle a C++ link name and prints the result.
6413 maintenance print type Print a type chain for a given symbol
6415 * Change to .gdbinit file processing
6417 We now read the $HOME/.gdbinit file before processing the argv arguments
6418 (e.g. reading symbol files or core files). This allows global parameters to
6419 be set, which will apply during the symbol reading. The ./.gdbinit is still
6420 read after argv processing.
6422 * New hosts supported
6424 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6426 GNU/Linux support i386-unknown-linux or linux
6428 We are also including code to support the HP/PA running BSD and HPUX. This
6429 is almost guaranteed not to work, as we didn't have time to test or build it
6430 for this release. We are including it so that the more adventurous (or
6431 masochistic) of you can play with it. We also had major problems with the
6432 fact that the compiler that we got from HP doesn't support the -g option.
6435 * New targets supported
6437 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6439 * More smarts about finding #include files
6441 GDB now remembers the compilation directory for all include files, and for
6442 all files from which C is generated (like yacc and lex sources). This
6443 greatly improves GDB's ability to find yacc/lex sources, and include files,
6444 especially if you are debugging your program from a directory different from
6445 the one that contains your sources.
6447 We also fixed a bug which caused difficulty with listing and setting
6448 breakpoints in include files which contain C code. (In the past, you had to
6449 try twice in order to list an include file that you hadn't looked at before.)
6451 * Interesting infernals change
6453 GDB now deals with arbitrary numbers of sections, where the symbols for each
6454 section must be relocated relative to that section's landing place in the
6455 target's address space. This work was needed to support ELF with embedded
6456 stabs used by Solaris-2.0.
6458 * Bug fixes (of course!)
6460 There have been loads of fixes for the following things:
6461 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6462 i960, stabs, DOS(GO32), procfs, etc...
6464 See the ChangeLog for details.
6466 *** Changes in GDB-4.5:
6468 * New machines supported (host and target)
6470 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6472 SGI Irix-4.x mips-sgi-irix4 or iris4
6474 * New malloc package
6476 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6477 Mmalloc is capable of handling mutiple heaps of memory. It is also
6478 capable of saving a heap to a file, and then mapping it back in later.
6479 This can be used to greatly speedup the startup of GDB by using a
6480 pre-parsed symbol table which lives in a mmalloc managed heap. For
6481 more details, please read mmalloc/mmalloc.texi.
6485 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6486 'help info proc' for details.
6488 * MIPS ecoff symbol table format
6490 The code that reads MIPS symbol table format is now supported on all hosts.
6491 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6494 * File name changes for MS-DOS
6496 Many files in the config directories have been renamed to make it easier to
6497 support GDB on MS-DOSe systems (which have very restrictive file name
6498 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6499 environment) is close to working but has some remaining problems. Note
6500 that debugging of DOS programs is not supported, due to limitations
6501 in the ``operating system'', but it can be used to host cross-debugging.
6503 * Cross byte order fixes
6505 Many fixes have been made to support cross debugging of Sparc and MIPS
6506 targets from hosts whose byte order differs.
6508 * New -mapped and -readnow options
6510 If memory-mapped files are available on your system through the 'mmap'
6511 system call, you can use the -mapped option on the `file' or
6512 `symbol-file' commands to cause GDB to write the symbols from your
6513 program into a reusable file. If the program you are debugging is
6514 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6515 Future GDB debugging sessions will notice the presence of this file,
6516 and will quickly map in symbol information from it, rather than reading
6517 the symbol table from the executable program. Using the '-mapped'
6518 option in a GDB `file' or `symbol-file' command has the same effect as
6519 starting GDB with the '-mapped' command-line option.
6521 You can cause GDB to read the entire symbol table immediately by using
6522 the '-readnow' option with any of the commands that load symbol table
6523 information (or on the GDB command line). This makes the command
6524 slower, but makes future operations faster.
6526 The -mapped and -readnow options are typically combined in order to
6527 build a `fred.syms' file that contains complete symbol information.
6528 A simple GDB invocation to do nothing but build a `.syms' file for future
6531 gdb -batch -nx -mapped -readnow programname
6533 The `.syms' file is specific to the host machine on which GDB is run.
6534 It holds an exact image of GDB's internal symbol table. It cannot be
6535 shared across multiple host platforms.
6537 * longjmp() handling
6539 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6540 siglongjmp() without losing control. This feature has not yet been ported to
6541 all systems. It currently works on many 386 platforms, all MIPS-based
6542 platforms (SGI, DECstation, etc), and Sun3/4.
6546 Preliminary work has been put in to support the new Solaris OS from Sun. At
6547 this time, it can control and debug processes, but it is not capable of
6552 As always, many many bug fixes. The major areas were with g++, and mipsread.
6553 People using the MIPS-based platforms should experience fewer mysterious
6554 crashes and trashed symbol tables.
6556 *** Changes in GDB-4.4:
6558 * New machines supported (host and target)
6560 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6562 BSD Reno on Vax vax-dec-bsd
6563 Ultrix on Vax vax-dec-ultrix
6565 * New machines supported (target)
6567 AMD 29000 embedded, using EBMON a29k-none-none
6571 GDB continues to improve its handling of C++. `References' work better.
6572 The demangler has also been improved, and now deals with symbols mangled as
6573 per the Annotated C++ Reference Guide.
6575 GDB also now handles `stabs' symbol information embedded in MIPS
6576 `ecoff' symbol tables. Since the ecoff format was not easily
6577 extensible to handle new languages such as C++, this appeared to be a
6578 good way to put C++ debugging info into MIPS binaries. This option
6579 will be supported in the GNU C compiler, version 2, when it is
6582 * New features for SVR4
6584 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6585 shared libraries. Debugging dynamically linked programs should present
6586 only minor differences from debugging statically linked programs.
6588 The `info proc' command will print out information about any process
6589 on an SVR4 system (including the one you are debugging). At the moment,
6590 it prints the address mappings of the process.
6592 If you bring up GDB on another SVR4 system, please send mail to
6593 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6595 * Better dynamic linking support in SunOS
6597 Reading symbols from shared libraries which contain debugging symbols
6598 now works properly. However, there remain issues such as automatic
6599 skipping of `transfer vector' code during function calls, which
6600 make it harder to debug code in a shared library, than to debug the
6601 same code linked statically.
6605 GDB is now using the latest `getopt' routines from the FSF. This
6606 version accepts the -- prefix for options with long names. GDB will
6607 continue to accept the old forms (-option and +option) as well.
6608 Various single letter abbreviations for options have been explicity
6609 added to the option table so that they won't get overshadowed in the
6610 future by other options that begin with the same letter.
6614 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6615 Many assorted bugs have been handled. Many more remain to be handled.
6616 See the various ChangeLog files (primarily in gdb and bfd) for details.
6619 *** Changes in GDB-4.3:
6621 * New machines supported (host and target)
6623 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6624 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6625 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6627 * Almost SCO Unix support
6629 We had hoped to support:
6630 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6631 (except for core file support), but we discovered very late in the release
6632 that it has problems with process groups that render gdb unusable. Sorry
6633 about that. I encourage people to fix it and post the fixes.
6635 * Preliminary ELF and DWARF support
6637 GDB can read ELF object files on System V Release 4, and can handle
6638 debugging records for C, in DWARF format, in ELF files. This support
6639 is preliminary. If you bring up GDB on another SVR4 system, please
6640 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6645 GDB now uses the latest `readline' library. One user-visible change
6646 is that two tabs will list possible command completions, which previously
6647 required typing M-? (meta-question mark, or ESC ?).
6651 The `stepi' bug that many of you noticed has been squashed.
6652 Many bugs in C++ have been handled. Many more remain to be handled.
6653 See the various ChangeLog files (primarily in gdb and bfd) for details.
6655 * State of the MIPS world (in case you wondered):
6657 GDB can understand the symbol tables emitted by the compilers
6658 supplied by most vendors of MIPS-based machines, including DEC. These
6659 symbol tables are in a format that essentially nobody else uses.
6661 Some versions of gcc come with an assembler post-processor called
6662 mips-tfile. This program is required if you want to do source-level
6663 debugging of gcc-compiled programs. I believe FSF does not ship
6664 mips-tfile with gcc version 1, but it will eventually come with gcc
6667 Debugging of g++ output remains a problem. g++ version 1.xx does not
6668 really support it at all. (If you're lucky, you should be able to get
6669 line numbers and stack traces to work, but no parameters or local
6670 variables.) With some work it should be possible to improve the
6673 When gcc version 2 is released, you will have somewhat better luck.
6674 However, even then you will get confusing results for inheritance and
6677 We will eventually provide full debugging of g++ output on
6678 DECstations. This will probably involve some kind of stabs-in-ecoff
6679 encapulation, but the details have not been worked out yet.
6682 *** Changes in GDB-4.2:
6684 * Improved configuration
6686 Only one copy of `configure' exists now, and it is not self-modifying.
6687 Porting BFD is simpler.
6691 The `step' and `next' commands now only stop at the first instruction
6692 of a source line. This prevents the multiple stops that used to occur
6693 in switch statements, for-loops, etc. `Step' continues to stop if a
6694 function that has debugging information is called within the line.
6698 Lots of small bugs fixed. More remain.
6700 * New host supported (not target)
6702 Intel 386 PC clone running Mach i386-none-mach
6705 *** Changes in GDB-4.1:
6707 * Multiple source language support
6709 GDB now has internal scaffolding to handle several source languages.
6710 It determines the type of each source file from its filename extension,
6711 and will switch expression parsing and number formatting to match the
6712 language of the function in the currently selected stack frame.
6713 You can also specifically set the language to be used, with
6714 `set language c' or `set language modula-2'.
6718 GDB now has preliminary support for the GNU Modula-2 compiler,
6719 currently under development at the State University of New York at
6720 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6721 continue through the fall of 1991 and into 1992.
6723 Other Modula-2 compilers are currently not supported, and attempting to
6724 debug programs compiled with them will likely result in an error as the
6725 symbol table is read. Feel free to work on it, though!
6727 There are hooks in GDB for strict type checking and range checking,
6728 in the `Modula-2 philosophy', but they do not currently work.
6732 GDB can now write to executable and core files (e.g. patch
6733 a variable's value). You must turn this switch on, specify
6734 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6735 by assigning a new value to a variable. Modifications take
6738 * Automatic SunOS shared library reading
6740 When you run your program, GDB automatically determines where its
6741 shared libraries (if any) have been loaded, and reads their symbols.
6742 The `share' command is no longer needed. This also works when
6743 examining core files.
6747 You can specify the number of lines that the `list' command shows.
6750 * New machines supported (host and target)
6752 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6753 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6754 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6756 * New hosts supported (not targets)
6758 IBM RT/PC: romp-ibm-aix or rtpc
6760 * New targets supported (not hosts)
6762 AMD 29000 embedded with COFF a29k-none-coff
6763 AMD 29000 embedded with a.out a29k-none-aout
6764 Ultracomputer remote kernel debug a29k-nyu-kern
6766 * New remote interfaces
6772 *** Changes in GDB-4.0:
6776 Wide output is wrapped at good places to make the output more readable.
6778 Gdb now supports cross-debugging from a host machine of one type to a
6779 target machine of another type. Communication with the target system
6780 is over serial lines. The ``target'' command handles connecting to the
6781 remote system; the ``load'' command will download a program into the
6782 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6783 also supports debugging of realtime processes running under VxWorks,
6784 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6785 stub on the target system.
6787 New CPUs supported include the AMD 29000 and Intel 960.
6789 GDB now reads object files and symbol tables via a ``binary file''
6790 library, which allows a single copy of GDB to debug programs of multiple
6791 object file types such as a.out and coff.
6793 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6794 refcard.dvi and refcard.ps are available to format it).
6797 * Control-Variable user interface simplified
6799 All variables that control the operation of the debugger can be set
6800 by the ``set'' command, and displayed by the ``show'' command.
6802 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6803 ``Show prompt'' produces the response:
6804 Gdb's prompt is new-gdb=>.
6806 What follows are the NEW set commands. The command ``help set'' will
6807 print a complete list of old and new set commands. ``help set FOO''
6808 will give a longer description of the variable FOO. ``show'' will show
6809 all of the variable descriptions and their current settings.
6811 confirm on/off: Enables warning questions for operations that are
6812 hard to recover from, e.g. rerunning the program while
6813 it is already running. Default is ON.
6815 editing on/off: Enables EMACS style command line editing
6816 of input. Previous lines can be recalled with
6817 control-P, the current line can be edited with control-B,
6818 you can search for commands with control-R, etc.
6821 history filename NAME: NAME is where the gdb command history
6822 will be stored. The default is .gdb_history,
6823 or the value of the environment variable
6826 history size N: The size, in commands, of the command history. The
6827 default is 256, or the value of the environment variable
6830 history save on/off: If this value is set to ON, the history file will
6831 be saved after exiting gdb. If set to OFF, the
6832 file will not be saved. The default is OFF.
6834 history expansion on/off: If this value is set to ON, then csh-like
6835 history expansion will be performed on
6836 command line input. The default is OFF.
6838 radix N: Sets the default radix for input and output. It can be set
6839 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6840 in the current radix, so "set radix 10" is always a no-op.
6842 height N: This integer value is the number of lines on a page. Default
6843 is 24, the current `stty rows'' setting, or the ``li#''
6844 setting from the termcap entry matching the environment
6847 width N: This integer value is the number of characters on a line.
6848 Default is 80, the current `stty cols'' setting, or the ``co#''
6849 setting from the termcap entry matching the environment
6852 Note: ``set screensize'' is obsolete. Use ``set height'' and
6853 ``set width'' instead.
6855 print address on/off: Print memory addresses in various command displays,
6856 such as stack traces and structure values. Gdb looks
6857 more ``symbolic'' if you turn this off; it looks more
6858 ``machine level'' with it on. Default is ON.
6860 print array on/off: Prettyprint arrays. New convenient format! Default
6863 print demangle on/off: Print C++ symbols in "source" form if on,
6866 print asm-demangle on/off: Same, for assembler level printouts
6869 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6872 * Support for Epoch Environment.
6874 The epoch environment is a version of Emacs v18 with windowing. One
6875 new command, ``inspect'', is identical to ``print'', except that if you
6876 are running in the epoch environment, the value is printed in its own
6880 * Support for Shared Libraries
6882 GDB can now debug programs and core files that use SunOS shared libraries.
6883 Symbols from a shared library cannot be referenced
6884 before the shared library has been linked with the program (this
6885 happens after you type ``run'' and before the function main() is entered).
6886 At any time after this linking (including when examining core files
6887 from dynamically linked programs), gdb reads the symbols from each
6888 shared library when you type the ``sharedlibrary'' command.
6889 It can be abbreviated ``share''.
6891 sharedlibrary REGEXP: Load shared object library symbols for files
6892 matching a unix regular expression. No argument
6893 indicates to load symbols for all shared libraries.
6895 info sharedlibrary: Status of loaded shared libraries.
6900 A watchpoint stops execution of a program whenever the value of an
6901 expression changes. Checking for this slows down execution
6902 tremendously whenever you are in the scope of the expression, but is
6903 quite useful for catching tough ``bit-spreader'' or pointer misuse
6904 problems. Some machines such as the 386 have hardware for doing this
6905 more quickly, and future versions of gdb will use this hardware.
6907 watch EXP: Set a watchpoint (breakpoint) for an expression.
6909 info watchpoints: Information about your watchpoints.
6911 delete N: Deletes watchpoint number N (same as breakpoints).
6912 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6913 enable N: Re-enables watchpoint number N (same as breakpoints).
6916 * C++ multiple inheritance
6918 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6921 * C++ exception handling
6923 Gdb now supports limited C++ exception handling. Besides the existing
6924 ability to breakpoint on an exception handler, gdb can breakpoint on
6925 the raising of an exception (before the stack is peeled back to the
6928 catch FOO: If there is a FOO exception handler in the dynamic scope,
6929 set a breakpoint to catch exceptions which may be raised there.
6930 Multiple exceptions (``catch foo bar baz'') may be caught.
6932 info catch: Lists all exceptions which may be caught in the
6933 current stack frame.
6936 * Minor command changes
6938 The command ``call func (arg, arg, ...)'' now acts like the print
6939 command, except it does not print or save a value if the function's result
6940 is void. This is similar to dbx usage.
6942 The ``up'' and ``down'' commands now always print the frame they end up
6943 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6944 frames without printing.
6946 * New directory command
6948 'dir' now adds directories to the FRONT of the source search path.
6949 The path starts off empty. Source files that contain debug information
6950 about the directory in which they were compiled can be found even
6951 with an empty path; Sun CC and GCC include this information. If GDB can't
6952 find your source file in the current directory, type "dir .".
6954 * Configuring GDB for compilation
6956 For normal use, type ``./configure host''. See README or gdb.texinfo
6959 GDB now handles cross debugging. If you are remotely debugging between
6960 two different machines, type ``./configure host -target=targ''.
6961 Host is the machine where GDB will run; targ is the machine
6962 where the program that you are debugging will run.