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".
380 *** Changes in GDB 7.12
382 * GDB and GDBserver now build with a C++ compiler by default.
384 The --enable-build-with-cxx configure option is now enabled by
385 default. One must now explicitly configure with
386 --disable-build-with-cxx in order to build with a C compiler. This
387 option will be removed in a future release.
389 * GDBserver now supports recording btrace without maintaining an active
392 * GDB now supports a negative repeat count in the 'x' command to examine
393 memory backward from the given address. For example:
396 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
397 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
398 (gdb) x/-5i 0x0000000000400580
399 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
400 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
401 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
402 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
403 0x40057b <main(int, char**)+25>:
404 callq 0x400536 <Func1(int, char const*)>
406 * Fortran: Support structures with fields of dynamic types and
407 arrays of dynamic types.
409 * The symbol dumping maintenance commands have new syntax.
410 maint print symbols [-pc address] [--] [filename]
411 maint print symbols [-objfile objfile] [-source source] [--] [filename]
412 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
413 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
414 maint print msymbols [-objfile objfile] [--] [filename]
416 * GDB now supports multibit bitfields and enums in target register
419 * New Python-based convenience function $_as_string(val), which returns
420 the textual representation of a value. This function is especially
421 useful to obtain the text label of an enum value.
423 * Intel MPX bound violation handling.
425 Segmentation faults caused by a Intel MPX boundary violation
426 now display the kind of violation (upper or lower), the memory
427 address accessed and the memory bounds, along with the usual
428 signal received and code location.
432 Program received signal SIGSEGV, Segmentation fault
433 Upper bound violation while accessing address 0x7fffffffc3b3
434 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
435 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
437 * Rust language support.
438 GDB now supports debugging programs written in the Rust programming
439 language. See https://www.rust-lang.org/ for more information about
442 * Support for running interpreters on specified input/output devices
444 GDB now supports a new mechanism that allows frontends to provide
445 fully featured GDB console views, as a better alternative to
446 building such views on top of the "-interpreter-exec console"
447 command. See the new "new-ui" command below. With that command,
448 frontends can now start GDB in the traditional command-line mode
449 running in an embedded terminal emulator widget, and create a
450 separate MI interpreter running on a specified i/o device. In this
451 way, GDB handles line editing, history, tab completion, etc. in the
452 console all by itself, and the GUI uses the separate MI interpreter
453 for its own control and synchronization, invisible to the command
456 * The "catch syscall" command catches groups of related syscalls.
458 The "catch syscall" command now supports catching a group of related
459 syscalls using the 'group:' or 'g:' prefix.
464 skip -gfile file-glob-pattern
465 skip -function function
466 skip -rfunction regular-expression
467 A generalized form of the skip command, with new support for
468 glob-style file names and regular expressions for function names.
469 Additionally, a file spec and a function spec may now be combined.
471 maint info line-table REGEXP
472 Display the contents of GDB's internal line table data struture.
475 Run any GDB unit tests that were compiled in.
478 Start a new user interface instance running INTERP as interpreter,
479 using the TTY file for input/output.
483 ** gdb.Breakpoint objects have a new attribute "pending", which
484 indicates whether the breakpoint is pending.
485 ** Three new breakpoint-related events have been added:
486 gdb.breakpoint_created, gdb.breakpoint_modified, and
487 gdb.breakpoint_deleted.
490 Signal ("set") the given MS-Windows event object. This is used in
491 conjunction with the Windows JIT debugging (AeDebug) support, where
492 the OS suspends a crashing process until a debugger can attach to
493 it. Resuming the crashing process, in order to debug it, is done by
496 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
497 was added in GDBserver, including JIT compiling fast tracepoint's
498 conditional expression bytecode into native code.
500 * Support for various remote target protocols and ROM monitors has
503 target m32rsdi Remote M32R debugging over SDI
504 target mips MIPS remote debugging protocol
505 target pmon PMON ROM monitor
506 target ddb NEC's DDB variant of PMON for Vr4300
507 target rockhopper NEC RockHopper variant of PMON
508 target lsi LSI variant of PMO
510 * Support for tracepoints and fast tracepoints on powerpc-linux,
511 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
512 including JIT compiling fast tracepoint's conditional expression
513 bytecode into native code.
515 * MI async record =record-started now includes the method and format used for
516 recording. For example:
518 =record-started,thread-group="i1",method="btrace",format="bts"
520 * MI async record =thread-selected now includes the frame field. For example:
522 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
526 Andes NDS32 nds32*-*-elf
528 *** Changes in GDB 7.11
530 * GDB now supports debugging kernel-based threads on FreeBSD.
532 * Per-inferior thread numbers
534 Thread numbers are now per inferior instead of global. If you're
535 debugging multiple inferiors, GDB displays thread IDs using a
536 qualified INF_NUM.THR_NUM form. For example:
540 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
541 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
542 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
543 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
545 As consequence, thread numbers as visible in the $_thread
546 convenience variable and in Python's InferiorThread.num attribute
547 are no longer unique between inferiors.
549 GDB now maintains a second thread ID per thread, referred to as the
550 global thread ID, which is the new equivalent of thread numbers in
551 previous releases. See also $_gthread below.
553 For backwards compatibility, MI's thread IDs always refer to global
556 * Commands that accept thread IDs now accept the qualified
557 INF_NUM.THR_NUM form as well. For example:
560 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
563 * In commands that accept a list of thread IDs, you can now refer to
564 all threads of an inferior using a star wildcard. GDB accepts
565 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
566 refer to all threads of the current inferior. For example, "info
569 * You can use "info threads -gid" to display the global thread ID of
572 * The new convenience variable $_gthread holds the global number of
575 * The new convenience variable $_inferior holds the number of the
578 * GDB now displays the ID and name of the thread that hit a breakpoint
579 or received a signal, if your program is multi-threaded. For
582 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
583 Thread 1 "main" received signal SIGINT, Interrupt.
585 * Record btrace now supports non-stop mode.
587 * Support for tracepoints on aarch64-linux was added in GDBserver.
589 * The 'record instruction-history' command now indicates speculative execution
590 when using the Intel Processor Trace recording format.
592 * GDB now allows users to specify explicit locations, bypassing
593 the linespec parser. This feature is also available to GDB/MI
596 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
597 GDB now is able to debug both AArch64 applications and ARM applications
600 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
601 including JIT compiling fast tracepoint's conditional expression bytecode
604 * GDB now supports displaced stepping on AArch64 GNU/Linux.
606 * "info threads", "info inferiors", "info display", "info checkpoints"
607 and "maint info program-spaces" now list the corresponding items in
608 ascending ID order, for consistency with all other "info" commands.
610 * In Ada, the overloads selection menu has been enhanced to display the
611 parameter types and the return types for the matching overloaded subprograms.
615 maint set target-non-stop (on|off|auto)
616 maint show target-non-stop
617 Control whether GDB targets always operate in non-stop mode even if
618 "set non-stop" is "off". The default is "auto", meaning non-stop
619 mode is enabled if supported by the target.
621 maint set bfd-sharing
622 maint show bfd-sharing
623 Control the reuse of bfd objects.
627 Control display of debugging info regarding bfd caching.
631 Control display of debugging info regarding FreeBSD threads.
633 set remote multiprocess-extensions-packet
634 show remote multiprocess-extensions-packet
635 Set/show the use of the remote protocol multiprocess extensions.
637 set remote thread-events
638 show remote thread-events
639 Set/show the use of thread create/exit events.
641 set ada print-signatures on|off
642 show ada print-signatures"
643 Control whether parameter types and return types are displayed in overloads
644 selection menus. It is activaled (@code{on}) by default.
648 Controls the maximum size of memory, in bytes, that GDB will
649 allocate for value contents. Prevents incorrect programs from
650 causing GDB to allocate overly large buffers. Default is 64k.
652 * The "disassemble" command accepts a new modifier: /s.
653 It prints mixed source+disassembly like /m with two differences:
654 - disassembled instructions are now printed in program order, and
655 - and source for all relevant files is now printed.
656 The "/m" option is now considered deprecated: its "source-centric"
657 output hasn't proved useful in practice.
659 * The "record instruction-history" command accepts a new modifier: /s.
660 It behaves exactly like /m and prints mixed source+disassembly.
662 * The "set scheduler-locking" command supports a new mode "replay".
663 It behaves like "off" in record mode and like "on" in replay mode.
665 * Support for various ROM monitors has been removed:
667 target dbug dBUG ROM monitor for Motorola ColdFire
668 target picobug Motorola picobug monitor
669 target dink32 DINK32 ROM monitor for PowerPC
670 target m32r Renesas M32R/D ROM monitor
671 target mon2000 mon2000 ROM monitor
672 target ppcbug PPCBUG ROM monitor for PowerPC
674 * Support for reading/writing memory and extracting values on architectures
675 whose memory is addressable in units of any integral multiple of 8 bits.
678 Allows to break when an Ada exception is handled.
683 Indicates that an exec system call was executed.
685 exec-events feature in qSupported
686 The qSupported packet allows GDB to request support for exec
687 events using the new 'gdbfeature' exec-event, and the qSupported
688 response can contain the corresponding 'stubfeature'. Set and
689 show commands can be used to display whether these features are enabled.
692 Equivalent to interrupting with the ^C character, but works in
695 thread created stop reason (T05 create:...)
696 Indicates that the thread was just created and is stopped at entry.
698 thread exit stop reply (w exitcode;tid)
699 Indicates that the thread has terminated.
702 Enables/disables thread create and exit event reporting. For
703 example, this is used in non-stop mode when GDB stops a set of
704 threads and synchronously waits for the their corresponding stop
705 replies. Without exit events, if one of the threads exits, GDB
706 would hang forever not knowing that it should no longer expect a
707 stop for that same thread.
710 Indicates that there are no resumed threads left in the target (all
711 threads are stopped). The remote stub reports support for this stop
712 reply to GDB's qSupported query.
715 Enables/disables catching syscalls from the inferior process.
716 The remote stub reports support for this packet to GDB's qSupported query.
718 syscall_entry stop reason
719 Indicates that a syscall was just called.
721 syscall_return stop reason
722 Indicates that a syscall just returned.
724 * Extended-remote exec events
726 ** GDB now has support for exec events on extended-remote Linux targets.
727 For such targets with Linux kernels 2.5.46 and later, this enables
728 follow-exec-mode and exec catchpoints.
730 set remote exec-event-feature-packet
731 show remote exec-event-feature-packet
732 Set/show the use of the remote exec event feature.
734 * Thread names in remote protocol
736 The reply to qXfer:threads:read may now include a name attribute for each
739 * Target remote mode fork and exec events
741 ** GDB now has support for fork and exec events on target remote mode
742 Linux targets. For such targets with Linux kernels 2.5.46 and later,
743 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
744 fork and exec catchpoints.
746 * Remote syscall events
748 ** GDB now has support for catch syscall on remote Linux targets,
749 currently enabled on x86/x86_64 architectures.
751 set remote catch-syscall-packet
752 show remote catch-syscall-packet
753 Set/show the use of the remote catch syscall feature.
757 ** The -var-set-format command now accepts the zero-hexadecimal
758 format. It outputs data in hexadecimal format with zero-padding on the
763 ** gdb.InferiorThread objects have a new attribute "global_num",
764 which refers to the thread's global thread ID. The existing
765 "num" attribute now refers to the thread's per-inferior number.
766 See "Per-inferior thread numbers" above.
767 ** gdb.InferiorThread objects have a new attribute "inferior", which
768 is the Inferior object the thread belongs to.
770 *** Changes in GDB 7.10
772 * Support for process record-replay and reverse debugging on aarch64*-linux*
773 targets has been added. GDB now supports recording of A64 instruction set
774 including advance SIMD instructions.
776 * Support for Sun's version of the "stabs" debug file format has been removed.
778 * GDB now honors the content of the file /proc/PID/coredump_filter
779 (PID is the process ID) on GNU/Linux systems. This file can be used
780 to specify the types of memory mappings that will be included in a
781 corefile. For more information, please refer to the manual page of
782 "core(5)". GDB also has a new command: "set use-coredump-filter
783 on|off". It allows to set whether GDB will read the content of the
784 /proc/PID/coredump_filter file when generating a corefile.
786 * The "info os" command on GNU/Linux can now display information on
788 "info os cpus" Listing of all cpus/cores on the system
790 * GDB has two new commands: "set serial parity odd|even|none" and
791 "show serial parity". These allows to set or show parity for the
794 * The "info source" command now displays the producer string if it was
795 present in the debug info. This typically includes the compiler version
796 and may include things like its command line arguments.
798 * The "info dll", an alias of the "info sharedlibrary" command,
799 is now available on all platforms.
801 * Directory names supplied to the "set sysroot" commands may be
802 prefixed with "target:" to tell GDB to access shared libraries from
803 the target system, be it local or remote. This replaces the prefix
804 "remote:". The default sysroot has been changed from "" to
805 "target:". "remote:" is automatically converted to "target:" for
806 backward compatibility.
808 * The system root specified by "set sysroot" will be prepended to the
809 filename of the main executable (if reported to GDB as absolute by
810 the operating system) when starting processes remotely, and when
811 attaching to already-running local or remote processes.
813 * GDB now supports automatic location and retrieval of executable
814 files from remote targets. Remote debugging can now be initiated
815 using only a "target remote" or "target extended-remote" command
816 (no "set sysroot" or "file" commands are required). See "New remote
819 * The "dump" command now supports verilog hex format.
821 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
823 * On GNU/Linux, GDB and gdbserver are now able to access executable
824 and shared library files without a "set sysroot" command when
825 attaching to processes running in different mount namespaces from
826 the debugger. This makes it possible to attach to processes in
827 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
828 See "New remote packets" below.
830 * The "tui reg" command now provides completion for all of the
831 available register groups, including target specific groups.
833 * The HISTSIZE environment variable is no longer read when determining
834 the size of GDB's command history. GDB now instead reads the dedicated
835 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
836 disables truncation of command history. Non-numeric values of GDBHISTSIZE
841 ** Memory ports can now be unbuffered.
845 ** gdb.Objfile objects have a new attribute "username",
846 which is the name of the objfile as specified by the user,
847 without, for example, resolving symlinks.
848 ** You can now write frame unwinders in Python.
849 ** gdb.Type objects have a new method "optimized_out",
850 returning optimized out gdb.Value instance of this type.
851 ** gdb.Value objects have new methods "reference_value" and
852 "const_value" which return a reference to the value and a
853 "const" version of the value respectively.
857 maint print symbol-cache
858 Print the contents of the symbol cache.
860 maint print symbol-cache-statistics
861 Print statistics of symbol cache usage.
863 maint flush-symbol-cache
864 Flush the contents of the symbol cache.
868 Start branch trace recording using Branch Trace Store (BTS) format.
871 Evaluate expression by using the compiler and print result.
875 Explicit commands for enabling and disabling tui mode.
878 set mpx bound on i386 and amd64
879 Support for bound table investigation on Intel MPX enabled applications.
883 Start branch trace recording using Intel Processor Trace format.
886 Print information about branch tracing internals.
888 maint btrace packet-history
889 Print the raw branch tracing data.
891 maint btrace clear-packet-history
892 Discard the stored raw branch tracing data.
895 Discard all branch tracing data. It will be fetched and processed
896 anew by the next "record" command.
901 Renamed from "set debug dwarf2-die".
903 Renamed from "show debug dwarf2-die".
906 Renamed from "set debug dwarf2-read".
907 show debug dwarf-read
908 Renamed from "show debug dwarf2-read".
910 maint set dwarf always-disassemble
911 Renamed from "maint set dwarf2 always-disassemble".
912 maint show dwarf always-disassemble
913 Renamed from "maint show dwarf2 always-disassemble".
915 maint set dwarf max-cache-age
916 Renamed from "maint set dwarf2 max-cache-age".
917 maint show dwarf max-cache-age
918 Renamed from "maint show dwarf2 max-cache-age".
921 show debug dwarf-line
922 Control display of debugging info regarding DWARF line processing.
926 Set the maximum number of candidates to be considered during
927 completion. The default value is 200. This limit allows GDB
928 to avoid generating large completion lists, the computation of
929 which can cause the debugger to become temporarily unresponsive.
931 set history remove-duplicates
932 show history remove-duplicates
933 Control the removal of duplicate history entries.
935 maint set symbol-cache-size
936 maint show symbol-cache-size
937 Control the size of the symbol cache.
939 set|show record btrace bts buffer-size
940 Set and show the size of the ring buffer used for branch tracing in
942 The obtained size may differ from the requested size. Use "info
943 record" to see the obtained buffer size.
945 set debug linux-namespaces
946 show debug linux-namespaces
947 Control display of debugging info regarding Linux namespaces.
949 set|show record btrace pt buffer-size
950 Set and show the size of the ring buffer used for branch tracing in
951 Intel Processor Trace format.
952 The obtained size may differ from the requested size. Use "info
953 record" to see the obtained buffer size.
955 maint set|show btrace pt skip-pad
956 Set and show whether PAD packets are skipped when computing the
959 * The command 'thread apply all' can now support new option '-ascending'
960 to call its specified command for all threads in ascending order.
962 * Python/Guile scripting
964 ** GDB now supports auto-loading of Python/Guile scripts contained in the
965 special section named `.debug_gdb_scripts'.
969 qXfer:btrace-conf:read
970 Return the branch trace configuration for the current thread.
972 Qbtrace-conf:bts:size
973 Set the requested ring buffer size for branch tracing in BTS format.
976 Enable Intel Procesor Trace-based branch tracing for the current
977 process. The remote stub reports support for this packet to GDB's
981 Set the requested ring buffer size for branch tracing in Intel Processor
985 Indicates a memory breakpoint instruction was executed, irrespective
986 of whether it was GDB that planted the breakpoint or the breakpoint
987 is hardcoded in the program. This is required for correct non-stop
991 Indicates the target stopped for a hardware breakpoint. This is
992 required for correct non-stop mode operation.
995 Return information about files on the remote system.
998 Return the full absolute name of the file that was executed to
999 create a process running on the remote system.
1002 Select the filesystem on which vFile: operations with filename
1003 arguments will operate. This is required for GDB to be able to
1004 access files on remote targets where the remote stub does not
1005 share a common filesystem with the inferior(s).
1008 Indicates that a fork system call was executed.
1011 Indicates that a vfork system call was executed.
1013 vforkdone stop reason
1014 Indicates that a vfork child of the specified process has executed
1015 an exec or exit, allowing the vfork parent to resume execution.
1017 fork-events and vfork-events features in qSupported
1018 The qSupported packet allows GDB to request support for fork and
1019 vfork events using new 'gdbfeatures' fork-events and vfork-events,
1020 and the qSupported response can contain the corresponding
1021 'stubfeatures'. Set and show commands can be used to display
1022 whether these features are enabled.
1024 * Extended-remote fork events
1026 ** GDB now has support for fork events on extended-remote Linux
1027 targets. For targets with Linux kernels 2.5.60 and later, this
1028 enables follow-fork-mode and detach-on-fork for both fork and
1029 vfork, as well as fork and vfork catchpoints.
1031 * The info record command now shows the recording format and the
1032 branch tracing configuration for the current thread when using
1033 the btrace record target.
1034 For the BTS format, it shows the ring buffer size.
1036 * GDB now has support for DTrace USDT (Userland Static Defined
1037 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
1039 * GDB now supports access to vector registers on S/390 GNU/Linux
1042 * Removed command line options
1044 -xdb HP-UX XDB compatibility mode.
1046 * Removed targets and native configurations
1048 HP/PA running HP-UX hppa*-*-hpux*
1049 Itanium running HP-UX ia64-*-hpux*
1051 * New configure options
1054 This configure option allows the user to build GDB with support for
1055 Intel Processor Trace (default: auto). This requires libipt.
1057 --with-libipt-prefix=PATH
1058 Specify the path to the version of libipt that GDB should use.
1059 $PATH/include should contain the intel-pt.h header and
1060 $PATH/lib should contain the libipt.so library.
1062 *** Changes in GDB 7.9.1
1066 ** Xmethods can now specify a result type.
1068 *** Changes in GDB 7.9
1070 * GDB now supports hardware watchpoints on x86 GNU Hurd.
1074 ** You can now access frame registers from Python scripts.
1075 ** New attribute 'producer' for gdb.Symtab objects.
1076 ** gdb.Objfile objects have a new attribute "progspace",
1077 which is the gdb.Progspace object of the containing program space.
1078 ** gdb.Objfile objects have a new attribute "owner".
1079 ** gdb.Objfile objects have a new attribute "build_id",
1080 which is the build ID generated when the file was built.
1081 ** gdb.Objfile objects have a new method "add_separate_debug_file".
1082 ** A new event "gdb.clear_objfiles" has been added, triggered when
1083 selecting a new file to debug.
1084 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
1085 ** New function gdb.lookup_objfile.
1087 New events which are triggered when GDB modifies the state of the
1090 ** gdb.events.inferior_call_pre: Function call is about to be made.
1091 ** gdb.events.inferior_call_post: Function call has just been made.
1092 ** gdb.events.memory_changed: A memory location has been altered.
1093 ** gdb.events.register_changed: A register has been altered.
1095 * New Python-based convenience functions:
1097 ** $_caller_is(name [, number_of_frames])
1098 ** $_caller_matches(regexp [, number_of_frames])
1099 ** $_any_caller_is(name [, number_of_frames])
1100 ** $_any_caller_matches(regexp [, number_of_frames])
1102 * GDB now supports the compilation and injection of source code into
1103 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
1104 to compile the source code to object code, and if successful, inject
1105 and execute that code within the current context of the inferior.
1106 Currently the C language is supported. The commands used to
1107 interface with this new feature are:
1109 compile code [-raw|-r] [--] [source code]
1110 compile file [-raw|-r] filename
1114 demangle [-l language] [--] name
1115 Demangle "name" in the specified language, or the current language
1116 if elided. This command is renamed from the "maint demangle" command.
1117 The latter is kept as a no-op to avoid "maint demangle" being interpreted
1118 as "maint demangler-warning".
1120 queue-signal signal-name-or-number
1121 Queue a signal to be delivered to the thread when it is resumed.
1123 add-auto-load-scripts-directory directory
1124 Add entries to the list of directories from which to load auto-loaded
1127 maint print user-registers
1128 List all currently available "user" registers.
1130 compile code [-r|-raw] [--] [source code]
1131 Compile, inject, and execute in the inferior the executable object
1132 code produced by compiling the provided source code.
1134 compile file [-r|-raw] filename
1135 Compile and inject into the inferior the executable object code
1136 produced by compiling the source code stored in the filename
1139 * On resume, GDB now always passes the signal the program had stopped
1140 for to the thread the signal was sent to, even if the user changed
1141 threads before resuming. Previously GDB would often (but not
1142 always) deliver the signal to the thread that happens to be current
1145 * Conversely, the "signal" command now consistently delivers the
1146 requested signal to the current thread. GDB now asks for
1147 confirmation if the program had stopped for a signal and the user
1148 switched threads meanwhile.
1150 * "breakpoint always-inserted" modes "off" and "auto" merged.
1152 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
1153 won't remove breakpoints from the target until all threads stop,
1154 even in non-stop mode. The "auto" mode has been removed, and "off"
1155 is now the default mode.
1159 set debug symbol-lookup
1160 show debug symbol-lookup
1161 Control display of debugging info regarding symbol lookup.
1165 ** The -list-thread-groups command outputs an exit-code field for
1166 inferiors that have exited.
1170 MIPS SDE mips*-sde*-elf*
1174 Support for these obsolete configurations has been removed.
1176 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
1177 SGI Irix-5.x mips-*-irix5*
1178 SGI Irix-6.x mips-*-irix6*
1179 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
1180 VAX running Ultrix vax-*-ultrix*
1182 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1183 and "assf"), have been removed. Use the "sharedlibrary" command, or
1184 its alias "share", instead.
1186 *** Changes in GDB 7.8
1188 * New command line options
1191 This is an alias for the --data-directory option.
1193 * GDB supports printing and modifying of variable length automatic arrays
1194 as specified in ISO C99.
1196 * The ARM simulator now supports instruction level tracing
1197 with or without disassembly.
1201 GDB now has support for scripting using Guile. Whether this is
1202 available is determined at configure time.
1203 Guile version 2.0 or greater is required.
1204 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
1206 * New commands (for set/show, see "New options" below)
1210 Invoke CODE by passing it to the Guile interpreter.
1214 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
1216 info auto-load guile-scripts [regexp]
1217 Print the list of automatically loaded Guile scripts.
1219 * The source command is now capable of sourcing Guile scripts.
1220 This feature is dependent on the debugger being built with Guile support.
1224 set print symbol-loading (off|brief|full)
1225 show print symbol-loading
1226 Control whether to print informational messages when loading symbol
1227 information for a file. The default is "full", but when debugging
1228 programs with large numbers of shared libraries the amount of output
1229 becomes less useful.
1231 set guile print-stack (none|message|full)
1232 show guile print-stack
1233 Show a stack trace when an error is encountered in a Guile script.
1235 set auto-load guile-scripts (on|off)
1236 show auto-load guile-scripts
1237 Control auto-loading of Guile script files.
1239 maint ada set ignore-descriptive-types (on|off)
1240 maint ada show ignore-descriptive-types
1241 Control whether the debugger should ignore descriptive types in Ada
1242 programs. The default is not to ignore the descriptive types. See
1243 the user manual for more details on descriptive types and the intended
1244 usage of this option.
1246 set auto-connect-native-target
1248 Control whether GDB is allowed to automatically connect to the
1249 native target for the run, attach, etc. commands when not connected
1250 to any target yet. See also "target native" below.
1252 set record btrace replay-memory-access (read-only|read-write)
1253 show record btrace replay-memory-access
1254 Control what memory accesses are allowed during replay.
1256 maint set target-async (on|off)
1257 maint show target-async
1258 This controls whether GDB targets operate in synchronous or
1259 asynchronous mode. Normally the default is asynchronous, if it is
1260 available; but this can be changed to more easily debug problems
1261 occurring only in synchronous mode.
1263 set mi-async (on|off)
1265 Control whether MI asynchronous mode is preferred. This supersedes
1266 "set target-async" of previous GDB versions.
1268 * "set target-async" is deprecated as a CLI option and is now an alias
1269 for "set mi-async" (only puts MI into async mode).
1271 * Background execution commands (e.g., "c&", "s&", etc.) are now
1272 possible ``out of the box'' if the target supports them. Previously
1273 the user would need to explicitly enable the possibility with the
1274 "set target-async on" command.
1276 * New features in the GDB remote stub, GDBserver
1278 ** New option --debug-format=option1[,option2,...] allows one to add
1279 additional text to each output. At present only timestamps
1280 are supported: --debug-format=timestamps.
1281 Timestamps can also be turned on with the
1282 "monitor set debug-format timestamps" command from GDB.
1284 * The 'record instruction-history' command now starts counting instructions
1285 at one. This also affects the instruction ranges reported by the
1286 'record function-call-history' command when given the /i modifier.
1288 * The command 'record function-call-history' supports a new modifier '/c' to
1289 indent the function names based on their call stack depth.
1290 The fields for the '/i' and '/l' modifier have been reordered.
1291 The source line range is now prefixed with 'at'.
1292 The instruction range is now prefixed with 'inst'.
1293 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1294 "record instruction-history" and "list" commands.
1296 * The ranges given as arguments to the 'record function-call-history' and
1297 'record instruction-history' commands are now inclusive.
1299 * The btrace record target now supports the 'record goto' command.
1300 For locations inside the execution trace, the back trace is computed
1301 based on the information stored in the execution trace.
1303 * The btrace record target supports limited reverse execution and replay.
1304 The target does not record data and therefore does not allow reading
1305 memory or registers.
1307 * The "catch syscall" command now works on s390*-linux* targets.
1309 * The "compare-sections" command is no longer specific to target
1310 remote. It now works with all targets.
1312 * All native targets are now consistently called "native".
1313 Consequently, the "target child", "target GNU", "target djgpp",
1314 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1315 commands have been replaced with "target native". The QNX/NTO port
1316 leaves the "procfs" target in place and adds a "native" target for
1317 consistency with other ports. The impact on users should be minimal
1318 as these commands previously either throwed an error, or were
1319 no-ops. The target's name is visible in the output of the following
1320 commands: "help target", "info target", "info files", "maint print
1323 * The "target native" command now connects to the native target. This
1324 can be used to launch native programs even when "set
1325 auto-connect-native-target" is set to off.
1327 * GDB now supports access to Intel MPX registers on GNU/Linux.
1329 * Support for Intel AVX-512 registers on GNU/Linux.
1330 Support displaying and modifying Intel AVX-512 registers
1331 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1333 * New remote packets
1335 qXfer:btrace:read's annex
1336 The qXfer:btrace:read packet supports a new annex 'delta' to read
1337 branch trace incrementally.
1341 ** Valid Python operations on gdb.Value objects representing
1342 structs/classes invoke the corresponding overloaded operators if
1344 ** New `Xmethods' feature in the Python API. Xmethods are
1345 additional methods or replacements for existing methods of a C++
1346 class. This feature is useful for those cases where a method
1347 defined in C++ source code could be inlined or optimized out by
1348 the compiler, making it unavailable to GDB.
1351 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1353 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1354 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1355 its alias "share", instead.
1357 * The commands "set remotebaud" and "show remotebaud" are no longer
1358 supported. Use "set serial baud" and "show serial baud" (respectively)
1363 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1364 target-async". The latter is left as a deprecated alias of the
1365 former for backward compatibility. If the target supports it,
1366 CLI background execution commands are now always possible by
1367 default, independently of whether the frontend stated a
1368 preference for asynchronous execution with "-gdb-set mi-async".
1369 Previously "-gdb-set target-async off" affected both MI execution
1370 commands and CLI execution commands.
1372 *** Changes in GDB 7.7
1374 * Improved support for process record-replay and reverse debugging on
1375 arm*-linux* targets. Support for thumb32 and syscall instruction
1376 recording has been added.
1378 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1380 * GDB now supports Fission DWP file format version 2.
1381 http://gcc.gnu.org/wiki/DebugFission
1383 * New convenience function "$_isvoid", to check whether an expression
1384 is void. A void expression is an expression where the type of the
1385 result is "void". For example, some convenience variables may be
1386 "void" when evaluated (e.g., "$_exitcode" before the execution of
1387 the program being debugged; or an undefined convenience variable).
1388 Another example, when calling a function whose return type is
1391 * The "maintenance print objfiles" command now takes an optional regexp.
1393 * The "catch syscall" command now works on arm*-linux* targets.
1395 * GDB now consistently shows "<not saved>" when printing values of
1396 registers the debug info indicates have not been saved in the frame
1397 and there's nowhere to retrieve them from
1398 (callee-saved/call-clobbered registers):
1403 (gdb) info registers rax
1406 Before, the former would print "<optimized out>", and the latter
1407 "*value not available*".
1409 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1414 ** Frame filters and frame decorators have been added.
1415 ** Temporary breakpoints are now supported.
1416 ** Line tables representation has been added.
1417 ** New attribute 'parent_type' for gdb.Field objects.
1418 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1419 ** New attribute 'name' for gdb.Type objects.
1423 Nios II ELF nios2*-*-elf
1424 Nios II GNU/Linux nios2*-*-linux
1425 Texas Instruments MSP430 msp430*-*-elf
1427 * Removed native configurations
1429 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1430 been removed. ELF variants of these configurations are kept supported.
1432 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1433 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1434 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1435 i[34567]86-*-openbsd3.[0-3]
1436 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1437 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1438 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1442 Like "catch throw", but catches a re-thrown exception.
1443 maint check-psymtabs
1444 Renamed from old "maint check-symtabs".
1446 Perform consistency checks on symtabs.
1447 maint expand-symtabs
1448 Expand symtabs matching an optional regexp.
1451 Display the details of GDB configure-time options.
1453 maint set|show per-command
1454 maint set|show per-command space
1455 maint set|show per-command time
1456 maint set|show per-command symtab
1457 Enable display of per-command gdb resource usage.
1459 remove-symbol-file FILENAME
1460 remove-symbol-file -a ADDRESS
1461 Remove a symbol file added via add-symbol-file. The file to remove
1462 can be identified by its filename or by an address that lies within
1463 the boundaries of this symbol file in memory.
1466 info exceptions REGEXP
1467 Display the list of Ada exceptions defined in the program being
1468 debugged. If provided, only the exceptions whose names match REGEXP
1473 set debug symfile off|on
1475 Control display of debugging info regarding reading symbol files and
1476 symbol tables within those files
1478 set print raw frame-arguments
1479 show print raw frame-arguments
1480 Set/show whether to print frame arguments in raw mode,
1481 disregarding any defined pretty-printers.
1483 set remote trace-status-packet
1484 show remote trace-status-packet
1485 Set/show the use of remote protocol qTStatus packet.
1489 Control display of debugging messages related to Nios II targets.
1493 Control whether target-assisted range stepping is enabled.
1495 set startup-with-shell
1496 show startup-with-shell
1497 Specifies whether Unix child processes are started via a shell or
1502 Use the target memory cache for accesses to the code segment. This
1503 improves performance of remote debugging (particularly disassembly).
1505 * You can now use a literal value 'unlimited' for options that
1506 interpret 0 or -1 as meaning "unlimited". E.g., "set
1507 trace-buffer-size unlimited" is now an alias for "set
1508 trace-buffer-size -1" and "set height unlimited" is now an alias for
1511 * The "set debug symtab-create" debugging option of GDB has been changed to
1512 accept a verbosity level. 0 means "off", 1 provides basic debugging
1513 output, and values of 2 or greater provides more verbose output.
1515 * New command-line options
1517 Display the details of GDB configure-time options.
1519 * The command 'tsave' can now support new option '-ctf' to save trace
1520 buffer in Common Trace Format.
1522 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1525 * GDB now implements the the C++ 'typeid' operator.
1527 * The new convenience variable $_exception holds the exception being
1528 thrown or caught at an exception-related catchpoint.
1530 * The exception-related catchpoints, like "catch throw", now accept a
1531 regular expression which can be used to filter exceptions by type.
1533 * The new convenience variable $_exitsignal is automatically set to
1534 the terminating signal number when the program being debugged dies
1535 due to an uncaught signal.
1539 ** All MI commands now accept an optional "--language" option.
1540 Support for this feature can be verified by using the "-list-features"
1541 command, which should contain "language-option".
1543 ** The new command -info-gdb-mi-command allows the user to determine
1544 whether a GDB/MI command is supported or not.
1546 ** The "^error" result record returned when trying to execute an undefined
1547 GDB/MI command now provides a variable named "code" whose content is the
1548 "undefined-command" error code. Support for this feature can be verified
1549 by using the "-list-features" command, which should contain
1550 "undefined-command-error-code".
1552 ** The -trace-save MI command can optionally save trace buffer in Common
1555 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1557 ** The command -data-list-register-values now accepts an optional
1558 "--skip-unavailable" option. When used, only the available registers
1561 ** The new command -trace-frame-collected dumps collected variables,
1562 computed expressions, tvars, memory and registers in a traceframe.
1564 ** The commands -stack-list-locals, -stack-list-arguments and
1565 -stack-list-variables now accept an option "--skip-unavailable".
1566 When used, only the available locals or arguments are displayed.
1568 ** The -exec-run command now accepts an optional "--start" option.
1569 When used, the command follows the same semantics as the "start"
1570 command, stopping the program's execution at the start of its
1571 main subprogram. Support for this feature can be verified using
1572 the "-list-features" command, which should contain
1573 "exec-run-start-option".
1575 ** The new commands -catch-assert and -catch-exceptions insert
1576 catchpoints stopping the program when Ada exceptions are raised.
1578 ** The new command -info-ada-exceptions provides the equivalent of
1579 the new "info exceptions" command.
1581 * New system-wide configuration scripts
1582 A GDB installation now provides scripts suitable for use as system-wide
1583 configuration scripts for the following systems:
1587 * GDB now supports target-assigned range stepping with remote targets.
1588 This improves the performance of stepping source lines by reducing
1589 the number of control packets from/to GDB. See "New remote packets"
1592 * GDB now understands the element 'tvar' in the XML traceframe info.
1593 It has the id of the collected trace state variables.
1595 * On S/390 targets that provide the transactional-execution feature,
1596 the program interruption transaction diagnostic block (TDB) is now
1597 represented as a number of additional "registers" in GDB.
1599 * New remote packets
1603 The vCont packet supports a new 'r' action, that tells the remote
1604 stub to step through an address range itself, without GDB
1605 involvemement at each single-step.
1607 qXfer:libraries-svr4:read's annex
1608 The previously unused annex of the qXfer:libraries-svr4:read packet
1609 is now used to support passing an argument list. The remote stub
1610 reports support for this argument list to GDB's qSupported query.
1611 The defined arguments are "start" and "prev", used to reduce work
1612 necessary for library list updating, resulting in significant
1615 * New features in the GDB remote stub, GDBserver
1617 ** GDBserver now supports target-assisted range stepping. Currently
1618 enabled on x86/x86_64 GNU/Linux targets.
1620 ** GDBserver now adds element 'tvar' in the XML in the reply to
1621 'qXfer:traceframe-info:read'. It has the id of the collected
1622 trace state variables.
1624 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1627 * New 'z' formatter for printing and examining memory, this displays the
1628 value as hexadecimal zero padded on the left to the size of the type.
1630 * GDB can now use Windows x64 unwinding data.
1632 * The "set remotebaud" command has been replaced by "set serial baud".
1633 Similarly, "show remotebaud" has been replaced by "show serial baud".
1634 The "set remotebaud" and "show remotebaud" commands are still available
1635 to provide backward compatibility with older versions of GDB.
1637 *** Changes in GDB 7.6
1639 * Target record has been renamed to record-full.
1640 Record/replay is now enabled with the "record full" command.
1641 This also affects settings that are associated with full record/replay
1642 that have been moved from "set/show record" to "set/show record full":
1644 set|show record full insn-number-max
1645 set|show record full stop-at-limit
1646 set|show record full memory-query
1648 * A new record target "record-btrace" has been added. The new target
1649 uses hardware support to record the control-flow of a process. It
1650 does not support replaying the execution, but it implements the
1651 below new commands for investigating the recorded execution log.
1652 This new recording method can be enabled using:
1656 The "record-btrace" target is only available on Intel Atom processors
1657 and requires a Linux kernel 2.6.32 or later.
1659 * Two new commands have been added for record/replay to give information
1660 about the recorded execution without having to replay the execution.
1661 The commands are only supported by "record btrace".
1663 record instruction-history prints the execution history at
1664 instruction granularity
1666 record function-call-history prints the execution history at
1667 function granularity
1669 * New native configurations
1671 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1672 FreeBSD/powerpc powerpc*-*-freebsd
1673 x86_64/Cygwin x86_64-*-cygwin*
1674 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1678 ARM AArch64 aarch64*-*-elf
1679 ARM AArch64 GNU/Linux aarch64*-*-linux
1680 Lynx 178 PowerPC powerpc-*-lynx*178
1681 x86_64/Cygwin x86_64-*-cygwin*
1682 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1684 * If the configured location of system.gdbinit file (as given by the
1685 --with-system-gdbinit option at configure time) is in the
1686 data-directory (as specified by --with-gdb-datadir at configure
1687 time) or in one of its subdirectories, then GDB will look for the
1688 system-wide init file in the directory specified by the
1689 --data-directory command-line option.
1691 * New command line options:
1693 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1694 other initialization files, unlike -nx which disables all of them.
1696 * Removed command line options
1698 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1701 * The 'ptype' and 'whatis' commands now accept an argument to control
1704 * 'info proc' now works on some core files.
1708 ** Vectors can be created with gdb.Type.vector.
1710 ** Python's atexit.register now works in GDB.
1712 ** Types can be pretty-printed via a Python API.
1714 ** Python 3 is now supported (in addition to Python 2.4 or later)
1716 ** New class gdb.Architecture exposes GDB's internal representation
1717 of architecture in the Python API.
1719 ** New method Frame.architecture returns the gdb.Architecture object
1720 corresponding to the frame's architecture.
1722 * New Python-based convenience functions:
1724 ** $_memeq(buf1, buf2, length)
1725 ** $_streq(str1, str2)
1727 ** $_regex(str, regex)
1729 * The 'cd' command now defaults to using '~' (the home directory) if not
1732 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1733 default for GCC since November 2000.
1735 * The command 'forward-search' can now be abbreviated as 'fo'.
1737 * The command 'info tracepoints' can now display 'installed on target'
1738 or 'not installed on target' for each non-pending location of tracepoint.
1740 * New configure options
1742 --enable-libmcheck/--disable-libmcheck
1743 By default, development versions are built with -lmcheck on hosts
1744 that support it, in order to help track memory corruption issues.
1745 Release versions, on the other hand, are built without -lmcheck
1746 by default. The --enable-libmcheck/--disable-libmcheck configure
1747 options allow the user to override that default.
1748 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1749 This configure option allows the user to build GDB with
1750 libbabeltrace using which GDB can read Common Trace Format data.
1752 * New commands (for set/show, see "New options" below)
1755 Catch signals. This is similar to "handle", but allows commands and
1756 conditions to be attached.
1759 List the BFDs known to GDB.
1761 python-interactive [command]
1763 Start a Python interactive prompt, or evaluate the optional command
1764 and print the result of expressions.
1767 "py" is a new alias for "python".
1769 enable type-printer [name]...
1770 disable type-printer [name]...
1771 Enable or disable type printers.
1775 ** For the Renesas Super-H architecture, the "regs" command has been removed
1776 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1781 set print type methods (on|off)
1782 show print type methods
1783 Control whether method declarations are displayed by "ptype".
1784 The default is to show them.
1786 set print type typedefs (on|off)
1787 show print type typedefs
1788 Control whether typedef definitions are displayed by "ptype".
1789 The default is to show them.
1791 set filename-display basename|relative|absolute
1792 show filename-display
1793 Control the way in which filenames is displayed.
1794 The default is "relative", which preserves previous behavior.
1796 set trace-buffer-size
1797 show trace-buffer-size
1798 Request target to change the size of trace buffer.
1800 set remote trace-buffer-size-packet auto|on|off
1801 show remote trace-buffer-size-packet
1802 Control the use of the remote protocol `QTBuffer:size' packet.
1806 Control display of debugging messages related to ARM AArch64.
1809 set debug coff-pe-read
1810 show debug coff-pe-read
1811 Control display of debugging messages related to reading of COFF/PE
1816 Control display of debugging messages related to Mach-O symbols
1819 set debug notification
1820 show debug notification
1821 Control display of debugging info for async remote notification.
1825 ** Command parameter changes are now notified using new async record
1826 "=cmd-param-changed".
1827 ** Trace frame changes caused by command "tfind" are now notified using
1828 new async record "=traceframe-changed".
1829 ** The creation, deletion and modification of trace state variables
1830 are now notified using new async records "=tsv-created",
1831 "=tsv-deleted" and "=tsv-modified".
1832 ** The start and stop of process record are now notified using new
1833 async record "=record-started" and "=record-stopped".
1834 ** Memory changes are now notified using new async record
1836 ** The data-disassemble command response will include a "fullname" field
1837 containing the absolute file name when source has been requested.
1838 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1839 command, to allow pattern filling of memory areas.
1840 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1841 library load/unload events.
1842 ** The response to breakpoint commands and breakpoint async records
1843 includes an "installed" field containing a boolean state about each
1844 non-pending tracepoint location is whether installed on target or not.
1845 ** Output of the "-trace-status" command includes a "trace-file" field
1846 containing the name of the trace file being examined. This field is
1847 optional, and only present when examining a trace file.
1848 ** The "fullname" field is now always present along with the "file" field,
1849 even if the file cannot be found by GDB.
1851 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1852 You must have the LZMA library available when configuring GDB for this
1853 feature to be enabled. For more information, see:
1854 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1856 * New remote packets
1859 Set the size of trace buffer. The remote stub reports support for this
1860 packet to gdb's qSupported query.
1863 Enable Branch Trace Store (BTS)-based branch tracing for the current
1864 thread. The remote stub reports support for this packet to gdb's
1868 Disable branch tracing for the current thread. The remote stub reports
1869 support for this packet to gdb's qSupported query.
1872 Read the traced branches for the current thread. The remote stub
1873 reports support for this packet to gdb's qSupported query.
1875 *** Changes in GDB 7.5
1877 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1878 for more x32 ABI info.
1880 * GDB now supports access to MIPS DSP registers on Linux targets.
1882 * GDB now supports debugging microMIPS binaries.
1884 * The "info os" command on GNU/Linux can now display information on
1885 several new classes of objects managed by the operating system:
1886 "info os procgroups" lists process groups
1887 "info os files" lists file descriptors
1888 "info os sockets" lists internet-domain sockets
1889 "info os shm" lists shared-memory regions
1890 "info os semaphores" lists semaphores
1891 "info os msg" lists message queues
1892 "info os modules" lists loaded kernel modules
1894 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1895 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1896 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1897 options and inspect the probe arguments using the new $_probe_arg family
1898 of convenience variables. You can obtain more information about SystemTap
1899 in <http://sourceware.org/systemtap/>.
1901 * GDB now supports reversible debugging on ARM, it allows you to
1902 debug basic ARM and THUMB instructions, and provides
1903 record/replay support.
1905 * The option "symbol-reloading" has been deleted as it is no longer used.
1909 ** GDB commands implemented in Python can now be put in command class
1912 ** The "maint set python print-stack on|off" is now deleted.
1914 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1915 apply "flag enum"-style pretty-printing to any enum.
1917 ** gdb.lookup_symbol can now work when there is no current frame.
1919 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1920 the source at which the symbol was defined.
1922 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1923 method 'value'. The former indicates whether the symbol needs a
1924 frame in order to compute its value, and the latter computes the
1927 ** A new method 'referenced_value' on gdb.Value objects which can
1928 dereference pointer as well as C++ reference values.
1930 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1931 which return the global and static blocks (as gdb.Block objects),
1932 of the underlying symbol table, respectively.
1934 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1935 object associated with a PC value.
1937 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1938 of the address range occupied by code for the current source line.
1940 * Go language support.
1941 GDB now supports debugging programs written in the Go programming
1944 * GDBserver now supports stdio connections.
1945 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1947 * The binary "gdbtui" can no longer be built or installed.
1948 Use "gdb -tui" instead.
1950 * GDB will now print "flag" enums specially. A flag enum is one where
1951 all the enumerator values have no bits in common when pairwise
1952 "and"ed. When printing a value whose type is a flag enum, GDB will
1953 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1954 (gdb) print (enum E) 3
1957 * The filename part of a linespec will now match trailing components
1958 of a source file name. For example, "break gcc/expr.c:1000" will
1959 now set a breakpoint in build/gcc/expr.c, but not
1960 build/libcpp/expr.c.
1962 * The "info proc" and "generate-core-file" commands will now also
1963 work on remote targets connected to GDBserver on Linux.
1965 * The command "info catch" has been removed. It has been disabled
1966 since December 2007.
1968 * The "catch exception" and "catch assert" commands now accept
1969 a condition at the end of the command, much like the "break"
1970 command does. For instance:
1972 (gdb) catch exception Constraint_Error if Barrier = True
1974 Previously, it was possible to add a condition to such catchpoints,
1975 but it had to be done as a second step, after the catchpoint had been
1976 created, using the "condition" command.
1978 * The "info static-tracepoint-marker" command will now also work on
1979 native Linux targets with in-process agent.
1981 * GDB can now set breakpoints on inlined functions.
1983 * The .gdb_index section has been updated to include symbols for
1984 inlined functions. GDB will ignore older .gdb_index sections by
1985 default, which could cause symbol files to be loaded more slowly
1986 until their .gdb_index sections can be recreated. The new command
1987 "set use-deprecated-index-sections on" will cause GDB to use any older
1988 .gdb_index sections it finds. This will restore performance, but the
1989 ability to set breakpoints on inlined functions will be lost in symbol
1990 files with older .gdb_index sections.
1992 The .gdb_index section has also been updated to record more information
1993 about each symbol. This speeds up the "info variables", "info functions"
1994 and "info types" commands when used with programs having the .gdb_index
1995 section, as well as speeding up debugging with shared libraries using
1996 the .gdb_index section.
1998 * Ada support for GDB/MI Variable Objects has been added.
2000 * GDB can now support 'breakpoint always-inserted mode' in 'record'
2005 ** New command -info-os is the MI equivalent of "info os".
2007 ** Output logs ("set logging" and related) now include MI output.
2011 ** "set use-deprecated-index-sections on|off"
2012 "show use-deprecated-index-sections on|off"
2013 Controls the use of deprecated .gdb_index sections.
2015 ** "catch load" and "catch unload" can be used to stop when a shared
2016 library is loaded or unloaded, respectively.
2018 ** "enable count" can be used to auto-disable a breakpoint after
2021 ** "info vtbl" can be used to show the virtual method tables for
2022 C++ and Java objects.
2024 ** "explore" and its sub commands "explore value" and "explore type"
2025 can be used to recursively explore values and types of
2026 expressions. These commands are available only if GDB is
2027 configured with '--with-python'.
2029 ** "info auto-load" shows status of all kinds of auto-loaded files,
2030 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
2031 sequences of commands files, "info auto-load python-scripts"
2032 shows status of auto-loading Python script files,
2033 "info auto-load local-gdbinit" shows status of loading init file
2034 (.gdbinit) from current directory and "info auto-load libthread-db" shows
2035 status of inferior specific thread debugging shared library loading.
2037 ** "info auto-load-scripts", "set auto-load-scripts on|off"
2038 and "show auto-load-scripts" commands have been deprecated, use their
2039 "info auto-load python-scripts", "set auto-load python-scripts on|off"
2040 and "show auto-load python-scripts" counterparts instead.
2042 ** "dprintf location,format,args..." creates a dynamic printf, which
2043 is basically a breakpoint that does a printf and immediately
2044 resumes your program's execution, so it is like a printf that you
2045 can insert dynamically at runtime instead of at compiletime.
2047 ** "set print symbol"
2049 Controls whether GDB attempts to display the symbol, if any,
2050 corresponding to addresses it prints. This defaults to "on", but
2051 you can set it to "off" to restore GDB's previous behavior.
2053 * Deprecated commands
2055 ** For the Renesas Super-H architecture, the "regs" command has been
2056 deprecated, and "info all-registers" should be used instead.
2060 Renesas RL78 rl78-*-elf
2061 HP OpenVMS ia64 ia64-hp-openvms*
2063 * GDBserver supports evaluation of breakpoint conditions. When
2064 support is advertised by GDBserver, GDB may be told to send the
2065 breakpoint conditions in bytecode form to GDBserver. GDBserver
2066 will only report the breakpoint trigger to GDB when its condition
2071 set mips compression
2072 show mips compression
2073 Select the compressed ISA encoding used in functions that have no symbol
2074 information available. The encoding can be set to either of:
2077 and is updated automatically from ELF file flags if available.
2079 set breakpoint condition-evaluation
2080 show breakpoint condition-evaluation
2081 Control whether breakpoint conditions are evaluated by GDB ("host") or by
2082 GDBserver ("target"). Default option "auto" chooses the most efficient
2084 This option can improve debugger efficiency depending on the speed of the
2088 Disable auto-loading globally.
2091 Show auto-loading setting of all kinds of auto-loaded files.
2093 set auto-load gdb-scripts on|off
2094 show auto-load gdb-scripts
2095 Control auto-loading of GDB canned sequences of commands files.
2097 set auto-load python-scripts on|off
2098 show auto-load python-scripts
2099 Control auto-loading of Python script files.
2101 set auto-load local-gdbinit on|off
2102 show auto-load local-gdbinit
2103 Control loading of init file (.gdbinit) from current directory.
2105 set auto-load libthread-db on|off
2106 show auto-load libthread-db
2107 Control auto-loading of inferior specific thread debugging shared library.
2109 set auto-load scripts-directory <dir1>[:<dir2>...]
2110 show auto-load scripts-directory
2111 Set a list of directories from which to load auto-loaded scripts.
2112 Automatically loaded Python scripts and GDB scripts are located in one
2113 of the directories listed by this option.
2114 The delimiter (':' above) may differ according to the host platform.
2116 set auto-load safe-path <dir1>[:<dir2>...]
2117 show auto-load safe-path
2118 Set a list of directories from which it is safe to auto-load files.
2119 The delimiter (':' above) may differ according to the host platform.
2121 set debug auto-load on|off
2122 show debug auto-load
2123 Control display of debugging info for auto-loading the files above.
2125 set dprintf-style gdb|call|agent
2127 Control the way in which a dynamic printf is performed; "gdb"
2128 requests a GDB printf command, while "call" causes dprintf to call a
2129 function in the inferior. "agent" requests that the target agent
2130 (such as GDBserver) do the printing.
2132 set dprintf-function <expr>
2133 show dprintf-function
2134 set dprintf-channel <expr>
2135 show dprintf-channel
2136 Set the function and optional first argument to the call when using
2137 the "call" style of dynamic printf.
2139 set disconnected-dprintf on|off
2140 show disconnected-dprintf
2141 Control whether agent-style dynamic printfs continue to be in effect
2142 after GDB disconnects.
2144 * New configure options
2146 --with-auto-load-dir
2147 Configure default value for the 'set auto-load scripts-directory'
2148 setting above. It defaults to '$debugdir:$datadir/auto-load',
2149 $debugdir representing global debugging info directories (available
2150 via 'show debug-file-directory') and $datadir representing GDB's data
2151 directory (available via 'show data-directory').
2153 --with-auto-load-safe-path
2154 Configure default value for the 'set auto-load safe-path' setting
2155 above. It defaults to the --with-auto-load-dir setting.
2157 --without-auto-load-safe-path
2158 Set 'set auto-load safe-path' to '/', effectively disabling this
2161 * New remote packets
2163 z0/z1 conditional breakpoints extension
2165 The z0/z1 breakpoint insertion packets have been extended to carry
2166 a list of conditional expressions over to the remote stub depending on the
2167 condition evaluation mode. The use of this extension can be controlled
2168 via the "set remote conditional-breakpoints-packet" command.
2172 Specify the signals which the remote stub may pass to the debugged
2173 program without GDB involvement.
2175 * New command line options
2177 --init-command=FILE, -ix Like --command, -x but execute it
2178 before loading inferior.
2179 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
2180 execute it before loading inferior.
2182 *** Changes in GDB 7.4
2184 * GDB now handles ambiguous linespecs more consistently; the existing
2185 FILE:LINE support has been expanded to other types of linespecs. A
2186 breakpoint will now be set on all matching locations in all
2187 inferiors, and locations will be added or removed according to
2190 * GDB now allows you to skip uninteresting functions and files when
2191 stepping with the "skip function" and "skip file" commands.
2193 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
2194 and "show remote hardware-watchpoint-length-limit". These allows to
2195 set or show the maximum length limit (in bytes) of a remote
2196 target hardware watchpoint.
2198 This allows e.g. to use "unlimited" hardware watchpoints with the
2199 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
2200 watchpoints are slower than real hardware watchpoints but are
2201 significantly faster than gdb software watchpoints.
2205 ** The register_pretty_printer function in module gdb.printing now takes
2206 an optional `replace' argument. If True, the new printer replaces any
2209 ** The "maint set python print-stack on|off" command has been
2210 deprecated and will be deleted in GDB 7.5.
2211 A new command: "set python print-stack none|full|message" has
2212 replaced it. Additionally, the default for "print-stack" is
2213 now "message", which just prints the error message without
2216 ** A prompt substitution hook (prompt_hook) is now available to the
2219 ** A new Python module, gdb.prompt has been added to the GDB Python
2220 modules library. This module provides functionality for
2221 escape sequences in prompts (used by set/show
2222 extended-prompt). These escape sequences are replaced by their
2223 corresponding value.
2225 ** Python commands and convenience-functions located in
2226 'data-directory'/python/gdb/command and
2227 'data-directory'/python/gdb/function are now automatically loaded
2230 ** Blocks now provide four new attributes. global_block and
2231 static_block will return the global and static blocks
2232 respectively. is_static and is_global are boolean attributes
2233 that indicate if the block is one of those two types.
2235 ** Symbols now provide the "type" attribute, the type of the symbol.
2237 ** The "gdb.breakpoint" function has been deprecated in favor of
2240 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2241 of a function. This class is based on the "finish" command
2242 available in the CLI.
2244 ** Type objects for struct and union types now allow access to
2245 the fields using standard Python dictionary (mapping) methods.
2246 For example, "some_type['myfield']" now works, as does
2247 "some_type.items()".
2249 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2252 ** A new function, "deep_items" has been added to the gdb.types
2253 module in the GDB Python modules library. This function returns
2254 an iterator over the fields of a struct or union type. Unlike
2255 the standard Python "iteritems" method, it will recursively traverse
2256 any anonymous fields.
2260 ** "*stopped" events can report several new "reason"s, such as
2263 ** Breakpoint changes are now notified using new async records, like
2264 "=breakpoint-modified".
2266 ** New command -ada-task-info.
2268 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2269 $sdir specifies the default system locations of shared libraries.
2270 $pdir specifies the directory where the libpthread used by the application
2273 GDB no longer looks in $sdir and $pdir after it has searched the directories
2274 mentioned in libthread-db-search-path. If you want to search those
2275 directories, they must be specified in libthread-db-search-path.
2276 The default value of libthread-db-search-path on GNU/Linux and Solaris
2277 systems is now "$sdir:$pdir".
2279 $pdir is not supported by gdbserver, it is currently ignored.
2280 $sdir is supported by gdbserver.
2282 * New configure option --with-iconv-bin.
2283 When using the internationalization support like the one in the GNU C
2284 library, GDB will invoke the "iconv" program to get a list of supported
2285 character sets. If this program lives in a non-standard location, one can
2286 use this option to specify where to find it.
2288 * When natively debugging programs on PowerPC BookE processors running
2289 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2290 watchpoints, which specify a mask in addition to an address to watch.
2291 The mask specifies that some bits of an address (the bits which are
2292 reset in the mask) should be ignored when matching the address accessed
2293 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2294 section in the user manual for more details.
2296 * The new option --once causes GDBserver to stop listening for connections once
2297 the first connection is made. The listening port used by GDBserver will
2298 become available after that.
2300 * New commands "info macros" and "alias" have been added.
2302 * New function parameters suffix @entry specifies value of function parameter
2303 at the time the function got called. Entry values are available only since
2309 "!" is now an alias of the "shell" command.
2310 Note that no space is needed between "!" and SHELL COMMAND.
2314 watch EXPRESSION mask MASK_VALUE
2315 The watch command now supports the mask argument which allows creation
2316 of masked watchpoints, if the current architecture supports this feature.
2318 info auto-load-scripts [REGEXP]
2319 This command was formerly named "maintenance print section-scripts".
2320 It is now generally useful and is no longer a maintenance-only command.
2322 info macro [-all] [--] MACRO
2323 The info macro command has new options `-all' and `--'. The first for
2324 printing all definitions of a macro. The second for explicitly specifying
2325 the end of arguments and the beginning of the macro name in case the macro
2326 name starts with a hyphen.
2328 collect[/s] EXPRESSIONS
2329 The tracepoint collect command now takes an optional modifier "/s"
2330 that directs it to dereference pointer-to-character types and
2331 collect the bytes of memory up to a zero byte. The behavior is
2332 similar to what you see when you use the regular print command on a
2333 string. An optional integer following the "/s" sets a bound on the
2334 number of bytes that will be collected.
2337 The trace start command now interprets any supplied arguments as a
2338 note to be recorded with the trace run, with an effect similar to
2339 setting the variable trace-notes.
2342 The trace stop command now interprets any arguments as a note to be
2343 mentioned along with the tstatus report that the trace was stopped
2344 with a command. The effect is similar to setting the variable
2347 * Tracepoints can now be enabled and disabled at any time after a trace
2348 experiment has been started using the standard "enable" and "disable"
2349 commands. It is now possible to start a trace experiment with no enabled
2350 tracepoints; GDB will display a warning, but will allow the experiment to
2351 begin, assuming that tracepoints will be enabled as needed while the trace
2354 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2355 locations with 4-byte instructions, when they were previously
2356 limited to locations with instructions of 5 bytes or longer.
2360 set debug dwarf2-read
2361 show debug dwarf2-read
2362 Turns on or off display of debugging messages related to reading
2363 DWARF debug info. The default is off.
2365 set debug symtab-create
2366 show debug symtab-create
2367 Turns on or off display of debugging messages related to symbol table
2368 creation. The default is off.
2371 show extended-prompt
2372 Set the GDB prompt, and allow escape sequences to be inserted to
2373 display miscellaneous information (see 'help set extended-prompt'
2374 for the list of sequences). This prompt (and any information
2375 accessed through the escape sequences) is updated every time the
2376 prompt is displayed.
2378 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2379 show print entry-values
2380 Set printing of frame argument values at function entry. In some cases
2381 GDB can determine the value of function argument which was passed by the
2382 function caller, even if the value was modified inside the called function.
2384 set debug entry-values
2385 show debug entry-values
2386 Control display of debugging info for determining frame argument values at
2387 function entry and virtual tail call frames.
2389 set basenames-may-differ
2390 show basenames-may-differ
2391 Set whether a source file may have multiple base names.
2392 (A "base name" is the name of a file with the directory part removed.
2393 Example: The base name of "/home/user/hello.c" is "hello.c".)
2394 If set, GDB will canonicalize file names (e.g., expand symlinks)
2395 before comparing them. Canonicalization is an expensive operation,
2396 but it allows the same file be known by more than one base name.
2397 If not set (the default), all source files are assumed to have just
2398 one base name, and gdb will do file name comparisons more efficiently.
2404 Set a user name and notes for the current and any future trace runs.
2405 This is useful for long-running and/or disconnected traces, to
2406 inform others (or yourself) as to who is running the trace, supply
2407 contact information, or otherwise explain what is going on.
2409 set trace-stop-notes
2410 show trace-stop-notes
2411 Set a note attached to the trace run, that is displayed when the
2412 trace has been stopped by a tstop command. This is useful for
2413 instance as an explanation, if you are stopping a trace run that was
2414 started by someone else.
2416 * New remote packets
2420 Dynamically enable a tracepoint in a started trace experiment.
2424 Dynamically disable a tracepoint in a started trace experiment.
2428 Set the user and notes of the trace run.
2432 Query the current status of a tracepoint.
2436 Query the minimum length of instruction at which a fast tracepoint may
2439 * Dcache size (number of lines) and line-size are now runtime-configurable
2440 via "set dcache line" and "set dcache line-size" commands.
2444 Texas Instruments TMS320C6x tic6x-*-*
2448 Renesas RL78 rl78-*-elf
2450 *** Changes in GDB 7.3.1
2452 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2454 *** Changes in GDB 7.3
2456 * GDB has a new command: "thread find [REGEXP]".
2457 It finds the thread id whose name, target id, or thread extra info
2458 matches the given regular expression.
2460 * The "catch syscall" command now works on mips*-linux* targets.
2462 * The -data-disassemble MI command now supports modes 2 and 3 for
2463 dumping the instruction opcodes.
2465 * New command line options
2467 -data-directory DIR Specify DIR as the "data-directory".
2468 This is mostly for testing purposes.
2470 * The "maint set python auto-load on|off" command has been renamed to
2471 "set auto-load-scripts on|off".
2473 * GDB has a new command: "set directories".
2474 It is like the "dir" command except that it replaces the
2475 source path list instead of augmenting it.
2477 * GDB now understands thread names.
2479 On GNU/Linux, "info threads" will display the thread name as set by
2480 prctl or pthread_setname_np.
2482 There is also a new command, "thread name", which can be used to
2483 assign a name internally for GDB to display.
2486 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2487 has been integrated into GDB.
2491 ** The function gdb.Write now accepts an optional keyword 'stream'.
2492 This keyword, when provided, will direct the output to either
2493 stdout, stderr, or GDB's logging output.
2495 ** Parameters can now be be sub-classed in Python, and in particular
2496 you may implement the get_set_doc and get_show_doc functions.
2497 This improves how Parameter set/show documentation is processed
2498 and allows for more dynamic content.
2500 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2501 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2502 have an is_valid method.
2504 ** Breakpoints can now be sub-classed in Python, and in particular
2505 you may implement a 'stop' function that is executed each time
2506 the inferior reaches that breakpoint.
2508 ** New function gdb.lookup_global_symbol looks up a global symbol.
2510 ** GDB values in Python are now callable if the value represents a
2511 function. For example, if 'some_value' represents a function that
2512 takes two integer parameters and returns a value, you can call
2513 that function like so:
2515 result = some_value (10,20)
2517 ** Module gdb.types has been added.
2518 It contains a collection of utilities for working with gdb.Types objects:
2519 get_basic_type, has_field, make_enum_dict.
2521 ** Module gdb.printing has been added.
2522 It contains utilities for writing and registering pretty-printers.
2523 New classes: PrettyPrinter, SubPrettyPrinter,
2524 RegexpCollectionPrettyPrinter.
2525 New function: register_pretty_printer.
2527 ** New commands "info pretty-printers", "enable pretty-printer" and
2528 "disable pretty-printer" have been added.
2530 ** gdb.parameter("directories") is now available.
2532 ** New function gdb.newest_frame returns the newest frame in the
2535 ** The gdb.InferiorThread class has a new "name" attribute. This
2536 holds the thread's name.
2538 ** Python Support for Inferior events.
2539 Python scripts can add observers to be notified of events
2540 occurring in the process being debugged.
2541 The following events are currently supported:
2542 - gdb.events.cont Continue event.
2543 - gdb.events.exited Inferior exited event.
2544 - gdb.events.stop Signal received, and Breakpoint hit events.
2548 ** GDB now puts template parameters in scope when debugging in an
2549 instantiation. For example, if you have:
2551 template<int X> int func (void) { return X; }
2553 then if you step into func<5>, "print X" will show "5". This
2554 feature requires proper debuginfo support from the compiler; it
2555 was added to GCC 4.5.
2557 ** The motion commands "next", "finish", "until", and "advance" now
2558 work better when exceptions are thrown. In particular, GDB will
2559 no longer lose control of the inferior; instead, the GDB will
2560 stop the inferior at the point at which the exception is caught.
2561 This functionality requires a change in the exception handling
2562 code that was introduced in GCC 4.5.
2564 * GDB now follows GCC's rules on accessing volatile objects when
2565 reading or writing target state during expression evaluation.
2566 One notable difference to prior behavior is that "print x = 0"
2567 no longer generates a read of x; the value of the assignment is
2568 now always taken directly from the value being assigned.
2570 * GDB now has some support for using labels in the program's source in
2571 linespecs. For instance, you can use "advance label" to continue
2572 execution to a label.
2574 * GDB now has support for reading and writing a new .gdb_index
2575 section. This section holds a fast index of DWARF debugging
2576 information and can be used to greatly speed up GDB startup and
2577 operation. See the documentation for `save gdb-index' for details.
2579 * The "watch" command now accepts an optional "-location" argument.
2580 When used, this causes GDB to watch the memory referred to by the
2581 expression. Such a watchpoint is never deleted due to it going out
2584 * GDB now supports thread debugging of core dumps on GNU/Linux.
2586 GDB now activates thread debugging using the libthread_db library
2587 when debugging GNU/Linux core dumps, similarly to when debugging
2588 live processes. As a result, when debugging a core dump file, GDB
2589 is now able to display pthread_t ids of threads. For example, "info
2590 threads" shows the same output as when debugging the process when it
2591 was live. In earlier releases, you'd see something like this:
2594 * 1 LWP 6780 main () at main.c:10
2596 While now you see this:
2599 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2601 It is also now possible to inspect TLS variables when debugging core
2604 When debugging a core dump generated on a machine other than the one
2605 used to run GDB, you may need to point GDB at the correct
2606 libthread_db library with the "set libthread-db-search-path"
2607 command. See the user manual for more details on this command.
2609 * When natively debugging programs on PowerPC BookE processors running
2610 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2611 which stop execution of the inferior whenever it executes an instruction
2612 at any address within the specified range. See the "PowerPC Embedded"
2613 section in the user manual for more details.
2615 * New features in the GDB remote stub, GDBserver
2617 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2618 and i686 LynxOS (version 5.x).
2620 ** GDBserver is now supported on Blackfin Linux.
2622 * New native configurations
2624 ia64 HP-UX ia64-*-hpux*
2628 Analog Devices, Inc. Blackfin Processor bfin-*
2630 * Ada task switching is now supported on sparc-elf targets when
2631 debugging a program using the Ravenscar Profile. For more information,
2632 see the "Tasking Support when using the Ravenscar Profile" section
2633 in the GDB user manual.
2635 * Guile support was removed.
2637 * New features in the GNU simulator
2639 ** The --map-info flag lists all known core mappings.
2641 ** CFI flashes may be simulated via the "cfi" device.
2643 *** Changes in GDB 7.2
2645 * Shared library support for remote targets by default
2647 When GDB is configured for a generic, non-OS specific target, like
2648 for example, --target=arm-eabi or one of the many *-*-elf targets,
2649 GDB now queries remote stubs for loaded shared libraries using the
2650 `qXfer:libraries:read' packet. Previously, shared library support
2651 was always disabled for such configurations.
2655 ** Argument Dependent Lookup (ADL)
2657 In C++ ADL lookup directs function search to the namespaces of its
2658 arguments even if the namespace has not been imported.
2668 Here the compiler will search for `foo' in the namespace of 'b'
2669 and find A::foo. GDB now supports this. This construct is commonly
2670 used in the Standard Template Library for operators.
2672 ** Improved User Defined Operator Support
2674 In addition to member operators, GDB now supports lookup of operators
2675 defined in a namespace and imported with a `using' directive, operators
2676 defined in the global scope, operators imported implicitly from an
2677 anonymous namespace, and the ADL operators mentioned in the previous
2679 GDB now also supports proper overload resolution for all the previously
2680 mentioned flavors of operators.
2682 ** static const class members
2684 Printing of static const class members that are initialized in the
2685 class definition has been fixed.
2687 * Windows Thread Information Block access.
2689 On Windows targets, GDB now supports displaying the Windows Thread
2690 Information Block (TIB) structure. This structure is visible either
2691 by using the new command `info w32 thread-information-block' or, by
2692 dereferencing the new convenience variable named `$_tlb', a
2693 thread-specific pointer to the TIB. This feature is also supported
2694 when remote debugging using GDBserver.
2696 * Static tracepoints
2698 Static tracepoints are calls in the user program into a tracing
2699 library. One such library is a port of the LTTng kernel tracer to
2700 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2701 When debugging with GDBserver, GDB now supports combining the GDB
2702 tracepoint machinery with such libraries. For example: the user can
2703 use GDB to probe a static tracepoint marker (a call from the user
2704 program into the tracing library) with the new "strace" command (see
2705 "New commands" below). This creates a "static tracepoint" in the
2706 breakpoint list, that can be manipulated with the same feature set
2707 as fast and regular tracepoints. E.g., collect registers, local and
2708 global variables, collect trace state variables, and define
2709 tracepoint conditions. In addition, the user can collect extra
2710 static tracepoint marker specific data, by collecting the new
2711 $_sdata internal variable. When analyzing the trace buffer, you can
2712 inspect $_sdata like any other variable available to GDB. For more
2713 information, see the "Tracepoints" chapter in GDB user manual. New
2714 remote packets have been defined to support static tracepoints, see
2715 the "New remote packets" section below.
2717 * Better reconstruction of tracepoints after disconnected tracing
2719 GDB will attempt to download the original source form of tracepoint
2720 definitions when starting a trace run, and then will upload these
2721 upon reconnection to the target, resulting in a more accurate
2722 reconstruction of the tracepoints that are in use on the target.
2726 You can now exercise direct control over the ways that GDB can
2727 affect your program. For instance, you can disallow the setting of
2728 breakpoints, so that the program can run continuously (assuming
2729 non-stop mode). In addition, the "observer" variable is available
2730 to switch all of the different controls; in observer mode, GDB
2731 cannot affect the target's behavior at all, which is useful for
2732 tasks like diagnosing live systems in the field.
2734 * The new convenience variable $_thread holds the number of the
2737 * New remote packets
2741 Return the address of the Windows Thread Information Block of a given thread.
2745 In response to several of the tracepoint packets, the target may now
2746 also respond with a number of intermediate `qRelocInsn' request
2747 packets before the final result packet, to have GDB handle
2748 relocating an instruction to execute at a different address. This
2749 is particularly useful for stubs that support fast tracepoints. GDB
2750 reports support for this feature in the qSupported packet.
2754 List static tracepoint markers in the target program.
2758 List static tracepoint markers at a given address in the target
2761 qXfer:statictrace:read
2763 Read the static trace data collected (by a `collect $_sdata'
2764 tracepoint action). The remote stub reports support for this packet
2765 to gdb's qSupported query.
2769 Send the current settings of GDB's permission flags.
2773 Send part of the source (textual) form of a tracepoint definition,
2774 which includes location, conditional, and action list.
2776 * The source command now accepts a -s option to force searching for the
2777 script in the source search path even if the script name specifies
2780 * New features in the GDB remote stub, GDBserver
2782 - GDBserver now support tracepoints (including fast tracepoints, and
2783 static tracepoints). The feature is currently supported by the
2784 i386-linux and amd64-linux builds. See the "Tracepoints support
2785 in gdbserver" section in the manual for more information.
2787 GDBserver JIT compiles the tracepoint's conditional agent
2788 expression bytecode into native code whenever possible for low
2789 overhead dynamic tracepoints conditionals. For such tracepoints,
2790 an expression that examines program state is evaluated when the
2791 tracepoint is reached, in order to determine whether to capture
2792 trace data. If the condition is simple and false, processing the
2793 tracepoint finishes very quickly and no data is gathered.
2795 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2796 for static tracepoints support.
2798 - GDBserver now supports x86_64 Windows 64-bit debugging.
2800 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2801 it understands register description.
2803 * The --batch flag now disables pagination and queries.
2805 * X86 general purpose registers
2807 GDB now supports reading/writing byte, word and double-word x86
2808 general purpose registers directly. This means you can use, say,
2809 $ah or $ax to refer, respectively, to the byte register AH and
2810 16-bit word register AX that are actually portions of the 32-bit
2811 register EAX or 64-bit register RAX.
2813 * The `commands' command now accepts a range of breakpoints to modify.
2814 A plain `commands' following a command that creates multiple
2815 breakpoints affects all the breakpoints set by that command. This
2816 applies to breakpoints set by `rbreak', and also applies when a
2817 single `break' command creates multiple breakpoints (e.g.,
2818 breakpoints on overloaded c++ functions).
2820 * The `rbreak' command now accepts a filename specification as part of
2821 its argument, limiting the functions selected by the regex to those
2822 in the specified file.
2824 * Support for remote debugging Windows and SymbianOS shared libraries
2825 from Unix hosts has been improved. Non Windows GDB builds now can
2826 understand target reported file names that follow MS-DOS based file
2827 system semantics, such as file names that include drive letters and
2828 use the backslash character as directory separator. This makes it
2829 possible to transparently use the "set sysroot" and "set
2830 solib-search-path" on Unix hosts to point as host copies of the
2831 target's shared libraries. See the new command "set
2832 target-file-system-kind" described below, and the "Commands to
2833 specify files" section in the user manual for more information.
2837 eval template, expressions...
2838 Convert the values of one or more expressions under the control
2839 of the string template to a command line, and call it.
2841 set target-file-system-kind unix|dos-based|auto
2842 show target-file-system-kind
2843 Set or show the assumed file system kind for target reported file
2846 save breakpoints <filename>
2847 Save all current breakpoint definitions to a file suitable for use
2848 in a later debugging session. To read the saved breakpoint
2849 definitions, use the `source' command.
2851 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2854 info static-tracepoint-markers
2855 Display information about static tracepoint markers in the target.
2857 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2858 Define a static tracepoint by probing a marker at the given
2859 function, line, address, or marker ID.
2863 Enable and disable observer mode.
2865 set may-write-registers on|off
2866 set may-write-memory on|off
2867 set may-insert-breakpoints on|off
2868 set may-insert-tracepoints on|off
2869 set may-insert-fast-tracepoints on|off
2870 set may-interrupt on|off
2871 Set individual permissions for GDB effects on the target. Note that
2872 some of these settings can have undesirable or surprising
2873 consequences, particularly when changed in the middle of a session.
2874 For instance, disabling the writing of memory can prevent
2875 breakpoints from being inserted, cause single-stepping to fail, or
2876 even crash your program, if you disable after breakpoints have been
2877 inserted. However, GDB should not crash.
2879 set record memory-query on|off
2880 show record memory-query
2881 Control whether to stop the inferior if memory changes caused
2882 by an instruction cannot be recorded.
2887 The disassemble command now supports "start,+length" form of two arguments.
2891 ** GDB now provides a new directory location, called the python directory,
2892 where Python scripts written for GDB can be installed. The location
2893 of that directory is <data-directory>/python, where <data-directory>
2894 is the GDB data directory. For more details, see section `Scripting
2895 GDB using Python' in the manual.
2897 ** The GDB Python API now has access to breakpoints, symbols, symbol
2898 tables, program spaces, inferiors, threads and frame's code blocks.
2899 Additionally, GDB Parameters can now be created from the API, and
2900 manipulated via set/show in the CLI.
2902 ** New functions gdb.target_charset, gdb.target_wide_charset,
2903 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2905 ** New exception gdb.GdbError.
2907 ** Pretty-printers are now also looked up in the current program space.
2909 ** Pretty-printers can now be individually enabled and disabled.
2911 ** GDB now looks for names of Python scripts to auto-load in a
2912 special section named `.debug_gdb_scripts', in addition to looking
2913 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2915 * Tracepoint actions were unified with breakpoint commands. In particular,
2916 there are no longer differences in "info break" output for breakpoints and
2917 tracepoints and the "commands" command can be used for both tracepoints and
2918 regular breakpoints.
2922 ARM Symbian arm*-*-symbianelf*
2924 * D language support.
2925 GDB now supports debugging programs written in the D programming
2928 * GDB now supports the extended ptrace interface for PowerPC which is
2929 available since Linux kernel version 2.6.34. This automatically enables
2930 any hardware breakpoints and additional hardware watchpoints available in
2931 the processor. The old ptrace interface exposes just one hardware
2932 watchpoint and no hardware breakpoints.
2934 * GDB is now able to use the Data Value Compare (DVC) register available on
2935 embedded PowerPC processors to implement in hardware simple watchpoint
2936 conditions of the form:
2938 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2940 This works in native GDB running on Linux kernels with the extended ptrace
2941 interface mentioned above.
2943 *** Changes in GDB 7.1
2947 ** Namespace Support
2949 GDB now supports importing of namespaces in C++. This enables the
2950 user to inspect variables from imported namespaces. Support for
2951 namepace aliasing has also been added. So, if a namespace is
2952 aliased in the current scope (e.g. namepace C=A; ) the user can
2953 print variables using the alias (e.g. (gdb) print C::x).
2957 All known bugs relating to the printing of virtual base class were
2958 fixed. It is now possible to call overloaded static methods using a
2963 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2964 and reinterpret_cast<> are now handled by the C++ expression parser.
2968 Xilinx MicroBlaze microblaze-*-*
2973 Xilinx MicroBlaze microblaze
2976 * Multi-program debugging.
2978 GDB now has support for multi-program (a.k.a. multi-executable or
2979 multi-exec) debugging. This allows for debugging multiple inferiors
2980 simultaneously each running a different program under the same GDB
2981 session. See "Debugging Multiple Inferiors and Programs" in the
2982 manual for more information. This implied some user visible changes
2983 in the multi-inferior support. For example, "info inferiors" now
2984 lists inferiors that are not running yet or that have exited
2985 already. See also "New commands" and "New options" below.
2987 * New tracing features
2989 GDB's tracepoint facility now includes several new features:
2991 ** Trace state variables
2993 GDB tracepoints now include support for trace state variables, which
2994 are variables managed by the target agent during a tracing
2995 experiment. They are useful for tracepoints that trigger each
2996 other, so for instance one tracepoint can count hits in a variable,
2997 and then a second tracepoint has a condition that is true when the
2998 count reaches a particular value. Trace state variables share the
2999 $-syntax of GDB convenience variables, and can appear in both
3000 tracepoint actions and condition expressions. Use the "tvariable"
3001 command to create, and "info tvariables" to view; see "Trace State
3002 Variables" in the manual for more detail.
3006 GDB now includes an option for defining fast tracepoints, which
3007 targets may implement more efficiently, such as by installing a jump
3008 into the target agent rather than a trap instruction. The resulting
3009 speedup can be by two orders of magnitude or more, although the
3010 tradeoff is that some program locations on some target architectures
3011 might not allow fast tracepoint installation, for instance if the
3012 instruction to be replaced is shorter than the jump. To request a
3013 fast tracepoint, use the "ftrace" command, with syntax identical to
3014 the regular trace command.
3016 ** Disconnected tracing
3018 It is now possible to detach GDB from the target while it is running
3019 a trace experiment, then reconnect later to see how the experiment
3020 is going. In addition, a new variable disconnected-tracing lets you
3021 tell the target agent whether to continue running a trace if the
3022 connection is lost unexpectedly.
3026 GDB now has the ability to save the trace buffer into a file, and
3027 then use that file as a target, similarly to you can do with
3028 corefiles. You can select trace frames, print data that was
3029 collected in them, and use tstatus to display the state of the
3030 tracing run at the moment that it was saved. To create a trace
3031 file, use "tsave <filename>", and to use it, do "target tfile
3034 ** Circular trace buffer
3036 You can ask the target agent to handle the trace buffer as a
3037 circular buffer, discarding the oldest trace frames to make room for
3038 newer ones, by setting circular-trace-buffer to on. This feature may
3039 not be available for all target agents.
3044 The disassemble command, when invoked with two arguments, now requires
3045 the arguments to be comma-separated.
3048 The info variables command now displays variable definitions. Files
3049 which only declare a variable are not shown.
3052 The source command is now capable of sourcing Python scripts.
3053 This feature is dependent on the debugger being build with Python
3056 Related to this enhancement is also the introduction of a new command
3057 "set script-extension" (see below).
3059 * New commands (for set/show, see "New options" below)
3061 record save [<FILENAME>]
3062 Save a file (in core file format) containing the process record
3063 execution log for replay debugging at a later time.
3065 record restore <FILENAME>
3066 Restore the process record execution log that was saved at an
3067 earlier time, for replay debugging.
3069 add-inferior [-copies <N>] [-exec <FILENAME>]
3072 clone-inferior [-copies <N>] [ID]
3073 Make a new inferior ready to execute the same program another
3074 inferior has loaded.
3079 maint info program-spaces
3080 List the program spaces loaded into GDB.
3082 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
3083 show remote interrupt-sequence
3084 Allow the user to select one of ^C, a BREAK signal or BREAK-g
3085 as the sequence to the remote target in order to interrupt the execution.
3086 Ctrl-C is a default. Some system prefers BREAK which is high level of
3087 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
3088 Magic SysRq g. It is BREAK signal and character 'g'.
3090 set remote interrupt-on-connect [on | off]
3091 show remote interrupt-on-connect
3092 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
3093 remote target when gdb connects to it. This is needed when you debug
3096 set remotebreak [on | off]
3098 Deprecated. Use "set/show remote interrupt-sequence" instead.
3100 tvariable $NAME [ = EXP ]
3101 Create or modify a trace state variable.
3104 List trace state variables and their values.
3106 delete tvariable $NAME ...
3107 Delete one or more trace state variables.
3110 Evaluate the given expressions without collecting anything into the
3111 trace buffer. (Valid in tracepoint actions only.)
3113 ftrace FN / FILE:LINE / *ADDR
3114 Define a fast tracepoint at the given function, line, or address.
3116 * New expression syntax
3118 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
3119 GDB now parses 0b101010 identically with 42.
3123 set follow-exec-mode new|same
3124 show follow-exec-mode
3125 Control whether GDB reuses the same inferior across an exec call or
3126 creates a new one. This is useful to be able to restart the old
3127 executable after the inferior having done an exec call.
3129 set default-collect EXPR, ...
3130 show default-collect
3131 Define a list of expressions to be collected at each tracepoint.
3132 This is a useful way to ensure essential items are not overlooked,
3133 such as registers or a critical global variable.
3135 set disconnected-tracing
3136 show disconnected-tracing
3137 If set to 1, the target is instructed to continue tracing if it
3138 loses its connection to GDB. If 0, the target is to stop tracing
3141 set circular-trace-buffer
3142 show circular-trace-buffer
3143 If set to on, the target is instructed to use a circular trace buffer
3144 and discard the oldest trace frames instead of stopping the trace due
3145 to a full trace buffer. If set to off, the trace stops when the buffer
3146 fills up. Some targets may not support this.
3148 set script-extension off|soft|strict
3149 show script-extension
3150 If set to "off", the debugger does not perform any script language
3151 recognition, and all sourced files are assumed to be GDB scripts.
3152 If set to "soft" (the default), files are sourced according to
3153 filename extension, falling back to GDB scripts if the first
3155 If set to "strict", files are sourced according to filename extension.
3157 set ada trust-PAD-over-XVS on|off
3158 show ada trust-PAD-over-XVS
3159 If off, activate a workaround against a bug in the debugging information
3160 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
3161 the GCC sources for more information about the GNAT encoding and
3162 PAD types in particular). It is always safe to set this option to
3163 off, but this introduces a slight performance penalty. The default
3166 * Python API Improvements
3168 ** GDB provides the new class gdb.LazyString. This is useful in
3169 some pretty-printing cases. The new method gdb.Value.lazy_string
3170 provides a simple way to create objects of this type.
3172 ** The fields returned by gdb.Type.fields now have an
3173 `is_base_class' attribute.
3175 ** The new method gdb.Type.range returns the range of an array type.
3177 ** The new method gdb.parse_and_eval can be used to parse and
3178 evaluate an expression.
3180 * New remote packets
3183 Define a trace state variable.
3186 Get the current value of a trace state variable.
3189 Set desired tracing behavior upon disconnection.
3192 Set the trace buffer to be linear or circular.
3195 Get data about the tracepoints currently in use.
3199 Process record now works correctly with hardware watchpoints.
3201 Multiple bug fixes have been made to the mips-irix port, making it
3202 much more reliable. In particular:
3203 - Debugging threaded applications is now possible again. Previously,
3204 GDB would hang while starting the program, or while waiting for
3205 the program to stop at a breakpoint.
3206 - Attaching to a running process no longer hangs.
3207 - An error occurring while loading a core file has been fixed.
3208 - Changing the value of the PC register now works again. This fixes
3209 problems observed when using the "jump" command, or when calling
3210 a function from GDB, or even when assigning a new value to $pc.
3211 - With the "finish" and "return" commands, the return value for functions
3212 returning a small array is now correctly printed.
3213 - It is now possible to break on shared library code which gets executed
3214 during a shared library init phase (code executed while executing
3215 their .init section). Previously, the breakpoint would have no effect.
3216 - GDB is now able to backtrace through the signal handler for
3217 non-threaded programs.
3219 PIE (Position Independent Executable) programs debugging is now supported.
3220 This includes debugging execution of PIC (Position Independent Code) shared
3221 libraries although for that, it should be possible to run such libraries as an
3224 *** Changes in GDB 7.0
3226 * GDB now has an interface for JIT compilation. Applications that
3227 dynamically generate code can create symbol files in memory and register
3228 them with GDB. For users, the feature should work transparently, and
3229 for JIT developers, the interface is documented in the GDB manual in the
3230 "JIT Compilation Interface" chapter.
3232 * Tracepoints may now be conditional. The syntax is as for
3233 breakpoints; either an "if" clause appended to the "trace" command,
3234 or the "condition" command is available. GDB sends the condition to
3235 the target for evaluation using the same bytecode format as is used
3236 for tracepoint actions.
3238 * The disassemble command now supports: an optional /r modifier, print the
3239 raw instructions in hex as well as in symbolic form, and an optional /m
3240 modifier to print mixed source+assembly.
3242 * Process record and replay
3244 In a architecture environment that supports ``process record and
3245 replay'', ``process record and replay'' target can record a log of
3246 the process execution, and replay it with both forward and reverse
3249 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3250 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3251 set execution-direction {forward|reverse}, for targets that support
3254 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3255 feature is available with a native GDB running on kernel version
3258 * GDB now has support for multi-byte and wide character sets on the
3259 target. Strings whose character type is wchar_t, char16_t, or
3260 char32_t are now correctly printed. GDB supports wide- and unicode-
3261 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3262 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3263 `printf'. This feature requires iconv to work properly; if your
3264 system does not have a working iconv, GDB can use GNU libiconv. See
3265 the installation instructions for more information.
3267 * GDB now supports automatic retrieval of shared library files from
3268 remote targets. To use this feature, specify a system root that begins
3269 with the `remote:' prefix, either via the `set sysroot' command or via
3270 the `--with-sysroot' configure-time option.
3272 * "info sharedlibrary" now takes an optional regex of libraries to show,
3273 and it now reports if a shared library has no debugging information.
3275 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3276 now complete on file names.
3278 * When completing in expressions, gdb will attempt to limit
3279 completions to allowable structure or union fields, where appropriate.
3280 For instance, consider:
3282 # struct example { int f1; double f2; };
3283 # struct example variable;
3286 If the user types TAB at the end of this command line, the available
3287 completions will be "f1" and "f2".
3289 * Inlined functions are now supported. They show up in backtraces, and
3290 the "step", "next", and "finish" commands handle them automatically.
3292 * GDB now supports the token-splicing (##) and stringification (#)
3293 operators when expanding macros. It also supports variable-arity
3296 * GDB now supports inspecting extra signal information, exported by
3297 the new $_siginfo convenience variable. The feature is currently
3298 implemented on linux ARM, i386 and amd64.
3300 * GDB can now display the VFP floating point registers and NEON vector
3301 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3302 can provide these registers (requires Linux 2.6.30 or later). Remote
3303 and simulator targets may also provide them.
3305 * New remote packets
3308 Search memory for a sequence of bytes.
3311 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3312 operation over reliable transport links. Use of this packet is
3313 controlled by the `set remote noack-packet' command.
3316 Kill the process with the specified process ID. Use this in preference
3317 to `k' when multiprocess protocol extensions are supported.
3320 Obtains additional operating system information
3324 Read or write additional signal information.
3326 * Removed remote protocol undocumented extension
3328 An undocumented extension to the remote protocol's `S' stop reply
3329 packet that permited the stub to pass a process id was removed.
3330 Remote servers should use the `T' stop reply packet instead.
3332 * GDB now supports multiple function calling conventions according to the
3333 DWARF-2 DW_AT_calling_convention function attribute.
3335 * The SH target utilizes the aforementioned change to distinguish between gcc
3336 and Renesas calling convention. It also adds the new CLI commands
3337 `set/show sh calling-convention'.
3339 * GDB can now read compressed debug sections, as produced by GNU gold
3340 with the --compress-debug-sections=zlib flag.
3342 * 64-bit core files are now supported on AIX.
3344 * Thread switching is now supported on Tru64.
3346 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3347 which will be allocated using malloc later in program execution.
3349 * The qXfer:libraries:read remote procotol packet now allows passing a
3350 list of section offsets.
3352 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3353 conditions handling signals delivered during attach or thread creation
3354 have also been fixed.
3356 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3357 From the user's standpoint, all unqualified instances of True and False
3358 are treated as the standard definitions, regardless of context.
3360 * GDB now parses C++ symbol and type names more flexibly. For
3363 template<typename T> class C { };
3366 GDB will now correctly handle all of:
3368 ptype C<char const *>
3369 ptype C<char const*>
3370 ptype C<const char *>
3371 ptype C<const char*>
3373 * New features in the GDB remote stub, gdbserver
3375 - The "--wrapper" command-line argument tells gdbserver to use a
3376 wrapper program to launch programs for debugging.
3378 - On PowerPC and S/390 targets, it is now possible to use a single
3379 gdbserver executable to debug both 32-bit and 64-bit programs.
3380 (This requires gdbserver itself to be built as a 64-bit executable.)
3382 - gdbserver uses the new noack protocol mode for TCP connections to
3383 reduce communications latency, if also supported and enabled in GDB.
3385 - Support for the sparc64-linux-gnu target is now included in
3388 - The amd64-linux build of gdbserver now supports debugging both
3389 32-bit and 64-bit programs.
3391 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3392 now support hardware watchpoints, and will use them automatically
3397 GDB now has support for scripting using Python. Whether this is
3398 available is determined at configure time.
3400 New GDB commands can now be written in Python.
3402 * Ada tasking support
3404 Ada tasks can now be inspected in GDB. The following commands have
3408 Print the list of Ada tasks.
3410 Print detailed information about task number N.
3412 Print the task number of the current task.
3414 Switch the context of debugging to task number N.
3416 * Support for user-defined prefixed commands. The "define" command can
3417 add new commands to existing prefixes, e.g. "target".
3419 * Multi-inferior, multi-process debugging.
3421 GDB now has generalized support for multi-inferior debugging. See
3422 "Debugging Multiple Inferiors" in the manual for more information.
3423 Although availability still depends on target support, the command
3424 set is more uniform now. The GNU/Linux specific multi-forks support
3425 has been migrated to this new framework. This implied some user
3426 visible changes; see "New commands" and also "Removed commands"
3429 * Target descriptions can now describe the target OS ABI. See the
3430 "Target Description Format" section in the user manual for more
3433 * Target descriptions can now describe "compatible" architectures
3434 to indicate that the target can execute applications for a different
3435 architecture in addition to those for the main target architecture.
3436 See the "Target Description Format" section in the user manual for
3439 * Multi-architecture debugging.
3441 GDB now includes general supports for debugging applications on
3442 hybrid systems that use more than one single processor architecture
3443 at the same time. Each such hybrid architecture still requires
3444 specific support to be added. The only hybrid architecture supported
3445 in this version of GDB is the Cell Broadband Engine.
3447 * GDB now supports integrated debugging of Cell/B.E. applications that
3448 use both the PPU and SPU architectures. To enable support for hybrid
3449 Cell/B.E. debugging, you need to configure GDB to support both the
3450 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3451 --enable-targets configure option.
3453 * Non-stop mode debugging.
3455 For some targets, GDB now supports an optional mode of operation in
3456 which you can examine stopped threads while other threads continue
3457 to execute freely. This is referred to as non-stop mode, with the
3458 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3459 section in the user manual for more information.
3461 To be able to support remote non-stop debugging, a remote stub needs
3462 to implement the non-stop mode remote protocol extensions, as
3463 described in the "Remote Non-Stop" section of the user manual. The
3464 GDB remote stub, gdbserver, has been adjusted to support these
3465 extensions on linux targets.
3467 * New commands (for set/show, see "New options" below)
3469 catch syscall [NAME(S) | NUMBER(S)]
3470 Catch system calls. Arguments, which should be names of system
3471 calls or their numbers, mean catch only those syscalls. Without
3472 arguments, every syscall will be caught. When the inferior issues
3473 any of the specified syscalls, GDB will stop and announce the system
3474 call, both when it is called and when its call returns. This
3475 feature is currently available with a native GDB running on the
3476 Linux Kernel, under the following architectures: x86, x86_64,
3477 PowerPC and PowerPC64.
3479 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3481 Search memory for a sequence of bytes.
3483 maint set python print-stack
3484 maint show python print-stack
3485 Show a stack trace when an error is encountered in a Python script.
3488 Invoke CODE by passing it to the Python interpreter.
3493 These allow macros to be defined, undefined, and listed
3497 Show operating system information about processes.
3500 List the inferiors currently under GDB's control.
3503 Switch focus to inferior number NUM.
3506 Detach from inferior number NUM.
3509 Kill inferior number NUM.
3513 set spu stop-on-load
3514 show spu stop-on-load
3515 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3517 set spu auto-flush-cache
3518 show spu auto-flush-cache
3519 Control whether to automatically flush the software-managed cache
3520 during Cell/B.E. debugging.
3522 set sh calling-convention
3523 show sh calling-convention
3524 Control the calling convention used when calling SH target functions.
3527 show debug timestamp
3528 Control display of timestamps with GDB debugging output.
3530 set disassemble-next-line
3531 show disassemble-next-line
3532 Control display of disassembled source lines or instructions when
3535 set remote noack-packet
3536 show remote noack-packet
3537 Set/show the use of remote protocol QStartNoAckMode packet. See above
3538 under "New remote packets."
3540 set remote query-attached-packet
3541 show remote query-attached-packet
3542 Control use of remote protocol `qAttached' (query-attached) packet.
3544 set remote read-siginfo-object
3545 show remote read-siginfo-object
3546 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3549 set remote write-siginfo-object
3550 show remote write-siginfo-object
3551 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3554 set remote reverse-continue
3555 show remote reverse-continue
3556 Control use of remote protocol 'bc' (reverse-continue) packet.
3558 set remote reverse-step
3559 show remote reverse-step
3560 Control use of remote protocol 'bs' (reverse-step) packet.
3562 set displaced-stepping
3563 show displaced-stepping
3564 Control displaced stepping mode. Displaced stepping is a way to
3565 single-step over breakpoints without removing them from the debuggee.
3566 Also known as "out-of-line single-stepping".
3569 show debug displaced
3570 Control display of debugging info for displaced stepping.
3572 maint set internal-error
3573 maint show internal-error
3574 Control what GDB does when an internal error is detected.
3576 maint set internal-warning
3577 maint show internal-warning
3578 Control what GDB does when an internal warning is detected.
3583 Use a wrapper program to launch programs for debugging.
3585 set multiple-symbols (all|ask|cancel)
3586 show multiple-symbols
3587 The value of this variable can be changed to adjust the debugger behavior
3588 when an expression or a breakpoint location contains an ambiguous symbol
3589 name (an overloaded function name, for instance).
3591 set breakpoint always-inserted
3592 show breakpoint always-inserted
3593 Keep breakpoints always inserted in the target, as opposed to inserting
3594 them when resuming the target, and removing them when the target stops.
3595 This option can improve debugger performance on slow remote targets.
3597 set arm fallback-mode (arm|thumb|auto)
3598 show arm fallback-mode
3599 set arm force-mode (arm|thumb|auto)
3601 These commands control how ARM GDB determines whether instructions
3602 are ARM or Thumb. The default for both settings is auto, which uses
3603 the current CPSR value for instructions without symbols; previous
3604 versions of GDB behaved as if "set arm fallback-mode arm".
3606 set disable-randomization
3607 show disable-randomization
3608 Standalone programs run with the virtual address space randomization enabled
3609 by default on some platforms. This option keeps the addresses stable across
3610 multiple debugging sessions.
3614 Control whether other threads are stopped or not when some thread hits
3619 Requests that asynchronous execution is enabled in the target, if available.
3620 In this case, it's possible to resume target in the background, and interact
3621 with GDB while the target is running. "show target-async" displays the
3622 current state of asynchronous execution of the target.
3624 set target-wide-charset
3625 show target-wide-charset
3626 The target-wide-charset is the name of the character set that GDB
3627 uses when printing characters whose type is wchar_t.
3629 set tcp auto-retry (on|off)
3631 set tcp connect-timeout
3632 show tcp connect-timeout
3633 These commands allow GDB to retry failed TCP connections to a remote stub
3634 with a specified timeout period; this is useful if the stub is launched
3635 in parallel with GDB but may not be ready to accept connections immediately.
3637 set libthread-db-search-path
3638 show libthread-db-search-path
3639 Control list of directories which GDB will search for appropriate
3642 set schedule-multiple (on|off)
3643 show schedule-multiple
3644 Allow GDB to resume all threads of all processes or only threads of
3645 the current process.
3649 Use more aggressive caching for accesses to the stack. This improves
3650 performance of remote debugging (particularly backtraces) without
3651 affecting correctness.
3653 set interactive-mode (on|off|auto)
3654 show interactive-mode
3655 Control whether GDB runs in interactive mode (on) or not (off).
3656 When in interactive mode, GDB waits for the user to answer all
3657 queries. Otherwise, GDB does not wait and assumes the default
3658 answer. When set to auto (the default), GDB determines which
3659 mode to use based on the stdin settings.
3664 For program forks, this is replaced by the new more generic `info
3665 inferiors' command. To list checkpoints, you can still use the
3666 `info checkpoints' command, which was an alias for the `info forks'
3670 Replaced by the new `inferior' command. To switch between
3671 checkpoints, you can still use the `restart' command, which was an
3672 alias for the `fork' command.
3675 This is removed, since some targets don't have a notion of
3676 processes. To switch between processes, you can still use the
3677 `inferior' command using GDB's own inferior number.
3680 For program forks, this is replaced by the new more generic `kill
3681 inferior' command. To delete a checkpoint, you can still use the
3682 `delete checkpoint' command, which was an alias for the `delete
3686 For program forks, this is replaced by the new more generic `detach
3687 inferior' command. To detach a checkpoint, you can still use the
3688 `detach checkpoint' command, which was an alias for the `detach
3691 * New native configurations
3693 x86/x86_64 Darwin i[34567]86-*-darwin*
3695 x86_64 MinGW x86_64-*-mingw*
3699 Lattice Mico32 lm32-*
3700 x86 DICOS i[34567]86-*-dicos*
3701 x86_64 DICOS x86_64-*-dicos*
3704 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3705 (mingw32ce) debugging.
3711 These commands were actually not implemented on any target.
3713 *** Changes in GDB 6.8
3715 * New native configurations
3717 NetBSD/hppa hppa*-*netbsd*
3718 Xtensa GNU/Linux xtensa*-*-linux*
3722 NetBSD/hppa hppa*-*-netbsd*
3723 Xtensa GNU/Lunux xtensa*-*-linux*
3725 * Change in command line behavior -- corefiles vs. process ids.
3727 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3728 attaching to process NUMBER fails, GDB no longer attempts to open a
3729 core file named NUMBER. Attaching to a program using the -c option
3730 is no longer supported. Instead, use the '-p' or '--pid' options.
3732 * GDB can now be built as a native debugger for debugging Windows x86
3733 (mingw32) Portable Executable (PE) programs.
3735 * Pending breakpoints no longer change their number when their address
3738 * GDB now supports breakpoints with multiple locations,
3739 including breakpoints on C++ constructors, inside C++ templates,
3740 and in inlined functions.
3742 * GDB's ability to debug optimized code has been improved. GDB more
3743 accurately identifies function bodies and lexical blocks that occupy
3744 more than one contiguous range of addresses.
3746 * Target descriptions can now describe registers for PowerPC.
3748 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3749 registers on PowerPC targets.
3751 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3752 targets even when the libthread_db library is not available.
3754 * The GDB remote stub, gdbserver, now supports the new file transfer
3755 commands (remote put, remote get, and remote delete).
3757 * The GDB remote stub, gdbserver, now supports run and attach in
3758 extended-remote mode.
3760 * hppa*64*-*-hpux11* target broken
3761 The debugger is unable to start a program and fails with the following
3762 error: "Error trying to get information about dynamic linker".
3763 The gdb-6.7 release is also affected.
3765 * GDB now supports the --enable-targets= configure option to allow
3766 building a single GDB executable that supports multiple remote
3767 target architectures.
3769 * GDB now supports debugging C and C++ programs which use the
3770 Decimal Floating Point extension. In addition, the PowerPC target
3771 now has a set of pseudo-registers to inspect decimal float values
3772 stored in two consecutive float registers.
3774 * The -break-insert MI command can optionally create pending
3777 * Improved support for debugging Ada
3778 Many improvements to the Ada language support have been made. These
3780 - Better support for Ada2005 interface types
3781 - Improved handling of arrays and slices in general
3782 - Better support for Taft-amendment types
3783 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3785 - Improved command completion in Ada
3788 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3793 set print frame-arguments (all|scalars|none)
3794 show print frame-arguments
3795 The value of this variable can be changed to control which argument
3796 values should be printed by the debugger when displaying a frame.
3801 Transfer files to and from a remote target, and delete remote files.
3808 Transfer files to and from a remote target, and delete remote files.
3810 * New remote packets
3817 Open, close, read, write, and delete files on the remote system.
3820 Attach to an existing process on the remote system, in extended-remote
3824 Run a new process on the remote system, in extended-remote mode.
3826 *** Changes in GDB 6.7
3828 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3829 bfd, libiberty and opcodes, as revealed by static analysis donated by
3830 Coverity, Inc. (http://scan.coverity.com).
3832 * When looking up multiply-defined global symbols, GDB will now prefer the
3833 symbol definition in the current shared library if it was built using the
3834 -Bsymbolic linker option.
3836 * When the Text User Interface (TUI) is not configured, GDB will now
3837 recognize the -tui command-line option and print a message that the TUI
3840 * The GDB remote stub, gdbserver, now has lower overhead for high
3841 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3843 * GDB for MIPS targets now autodetects whether a remote target provides
3844 32-bit or 64-bit register values.
3846 * Support for C++ member pointers has been improved.
3848 * GDB now understands XML target descriptions, which specify the
3849 target's overall architecture. GDB can read a description from
3850 a local file or over the remote serial protocol.
3852 * Vectors of single-byte data use a new integer type which is not
3853 automatically displayed as character or string data.
3855 * The /s format now works with the print command. It displays
3856 arrays of single-byte integers and pointers to single-byte integers
3859 * Target descriptions can now describe target-specific registers,
3860 for architectures which have implemented the support (currently
3861 only ARM, M68K, and MIPS).
3863 * GDB and the GDB remote stub, gdbserver, now support the XScale
3866 * The GDB remote stub, gdbserver, has been updated to support
3867 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3868 has been rewritten to use the standard GDB remote protocol.
3870 * GDB can now step into C++ functions which are called through thunks.
3872 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3874 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3875 layout. It also supports a TextSeg= and DataSeg= response when only
3876 segment base addresses (rather than offsets) are available.
3878 * The /i format now outputs any trailing branch delay slot instructions
3879 immediately following the last instruction within the count specified.
3881 * The GDB remote protocol "T" stop reply packet now supports a
3882 "library" response. Combined with the new "qXfer:libraries:read"
3883 packet, this response allows GDB to debug shared libraries on targets
3884 where the operating system manages the list of loaded libraries (e.g.
3885 Windows and SymbianOS).
3887 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3888 (DLLs) on Windows and Windows CE targets.
3890 * GDB now supports a faster verification that a .debug file matches its binary
3891 according to its build-id signature, if the signature is present.
3897 Enable or disable hardware flow control (RTS/CTS) on the serial port
3898 when debugging using remote targets.
3900 set mem inaccessible-by-default
3901 show mem inaccessible-by-default
3902 If the target supplies a memory map, for instance via the remote
3903 protocol's "qXfer:memory-map:read" packet, setting this variable
3904 prevents GDB from accessing memory outside the memory map. This
3905 is useful for targets with memory mapped registers or which react
3906 badly to accesses of unmapped address space.
3908 set breakpoint auto-hw
3909 show breakpoint auto-hw
3910 If the target supplies a memory map, for instance via the remote
3911 protocol's "qXfer:memory-map:read" packet, setting this variable
3912 lets GDB use hardware breakpoints automatically for memory regions
3913 where it can not use software breakpoints. This covers both the
3914 "break" command and internal breakpoints used for other commands
3915 including "next" and "finish".
3918 catch exception unhandled
3919 Stop the program execution when Ada exceptions are raised.
3922 Stop the program execution when an Ada assertion failed.
3926 Set an alternate system root for target files. This is a more
3927 general version of "set solib-absolute-prefix", which is now
3928 an alias to "set sysroot".
3931 Provide extended SPU facility status information. This set of
3932 commands is available only when debugging the Cell/B.E. SPU
3935 * New native configurations
3937 OpenBSD/sh sh*-*openbsd*
3940 unset tdesc filename
3942 Use the specified local file as an XML target description, and do
3943 not query the target for its built-in description.
3947 OpenBSD/sh sh*-*-openbsd*
3948 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3949 Toshiba Media Processor mep-elf
3951 * New remote packets
3954 Ignore the specified signals; pass them directly to the debugged program
3955 without stopping other threads or reporting them to GDB.
3957 qXfer:features:read:
3958 Read an XML target description from the target, which describes its
3963 Read or write contents of an spufs file on the target system. These
3964 packets are available only on the Cell/B.E. SPU architecture.
3966 qXfer:libraries:read:
3967 Report the loaded shared libraries. Combined with new "T" packet
3968 response, this packet allows GDB to debug shared libraries on
3969 targets where the operating system manages the list of loaded
3970 libraries (e.g. Windows and SymbianOS).
3974 Support for these obsolete configurations has been removed.
3982 i[34567]86-*-lynxos*
3983 i[34567]86-*-netware*
3984 i[34567]86-*-sco3.2v5*
3985 i[34567]86-*-sco3.2v4*
3987 i[34567]86-*-sysv4.2*
3990 i[34567]86-*-unixware2*
3991 i[34567]86-*-unixware*
4000 * Other removed features
4007 Various m68k-only ROM monitors.
4014 Various Renesas ROM monitors and debugging interfaces for SH and
4019 Support for a Macraigor serial interface to on-chip debugging.
4020 GDB does not directly support the newer parallel or USB
4025 A debug information format. The predecessor to DWARF 2 and
4026 DWARF 3, which are still supported.
4028 Support for the HP aCC compiler on HP-UX/PA-RISC
4030 SOM-encapsulated symbolic debugging information, automatic
4031 invocation of pxdb, and the aCC custom C++ ABI. This does not
4032 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
4033 with aCC can still be debugged on an assembly level.
4035 MIPS ".pdr" sections
4037 A MIPS-specific format used to describe stack frame layout
4038 in debugging information.
4042 GDB could work with an older version of Guile to debug
4043 the interpreter and Scheme programs running in it.
4045 set mips stack-arg-size
4046 set mips saved-gpreg-size
4048 Use "set mips abi" to control parameter passing for MIPS.
4050 *** Changes in GDB 6.6
4055 Cell Broadband Engine SPU spu-elf
4057 * GDB can now be configured as a cross-debugger targeting native Windows
4058 (mingw32) or Cygwin. It can communicate with a remote debugging stub
4059 running on a Windows system over TCP/IP to debug Windows programs.
4061 * The GDB remote stub, gdbserver, has been updated to support Windows and
4062 Cygwin debugging. Both single-threaded and multi-threaded programs are
4065 * The "set trust-readonly-sections" command works again. This command was
4066 broken in GDB 6.3, 6.4, and 6.5.
4068 * The "load" command now supports writing to flash memory, if the remote
4069 stub provides the required support.
4071 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
4072 longer requires symbolic debug information (e.g. DWARF-2).
4077 unset substitute-path
4078 show substitute-path
4079 Manage a list of substitution rules that GDB uses to rewrite the name
4080 of the directories where the sources are located. This can be useful
4081 for instance when the sources were moved to a different location
4082 between compilation and debugging.
4086 Print each CLI command as it is executed. Each command is prefixed with
4087 a number of `+' symbols representing the nesting depth.
4088 The source command now has a `-v' option to enable the same feature.
4092 The ARM Demon monitor support (RDP protocol, "target rdp").
4094 Kernel Object Display, an embedded debugging feature which only worked with
4095 an obsolete version of Cisco IOS.
4097 The 'set download-write-size' and 'show download-write-size' commands.
4099 * New remote packets
4102 Tell a stub about GDB client features, and request remote target features.
4103 The first feature implemented is PacketSize, which allows the target to
4104 specify the size of packets it can handle - to minimize the number of
4105 packets required and improve performance when connected to a remote
4109 Fetch an OS auxilliary vector from the remote stub. This packet is a
4110 more efficient replacement for qPart:auxv:read.
4112 qXfer:memory-map:read:
4113 Fetch a memory map from the remote stub, including information about
4114 RAM, ROM, and flash memory devices.
4119 Erase and program a flash memory device.
4121 * Removed remote packets
4124 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
4125 used it, and only gdbserver implemented it.
4127 *** Changes in GDB 6.5
4131 Renesas M32C/M16C m32c-elf
4133 Morpho Technologies ms1 ms1-elf
4137 init-if-undefined Initialize a convenience variable, but
4138 only if it doesn't already have a value.
4140 The following commands are presently only implemented for native GNU/Linux:
4142 checkpoint Save a snapshot of the program state.
4144 restart <n> Return the program state to a
4145 previously saved state.
4147 info checkpoints List currently saved checkpoints.
4149 delete-checkpoint <n> Delete a previously saved checkpoint.
4151 set|show detach-on-fork Tell gdb whether to detach from a newly
4152 forked process, or to keep debugging it.
4154 info forks List forks of the user program that
4155 are available to be debugged.
4157 fork <n> Switch to debugging one of several
4158 forks of the user program that are
4159 available to be debugged.
4161 delete-fork <n> Delete a fork from the list of forks
4162 that are available to be debugged (and
4163 kill the forked process).
4165 detach-fork <n> Delete a fork from the list of forks
4166 that are available to be debugged (and
4167 allow the process to continue).
4171 Morpho Technologies ms2 ms1-elf
4173 * Improved Windows host support
4175 GDB now builds as a cross debugger hosted on i686-mingw32, including
4176 native console support, and remote communications using either
4177 network sockets or serial ports.
4179 * Improved Modula-2 language support
4181 GDB can now print most types in the Modula-2 syntax. This includes:
4182 basic types, set types, record types, enumerated types, range types,
4183 pointer types and ARRAY types. Procedure var parameters are correctly
4184 printed and hexadecimal addresses and character constants are also
4185 written in the Modula-2 syntax. Best results can be obtained by using
4186 GNU Modula-2 together with the -gdwarf-2 command line option.
4190 The ARM rdi-share module.
4192 The Netware NLM debug server.
4194 *** Changes in GDB 6.4
4196 * New native configurations
4198 OpenBSD/arm arm*-*-openbsd*
4199 OpenBSD/mips64 mips64-*-openbsd*
4203 Morpho Technologies ms1 ms1-elf
4205 * New command line options
4207 --batch-silent As for --batch, but totally silent.
4208 --return-child-result The debugger will exist with the same value
4209 the child (debugged) program exited with.
4210 --eval-command COMMAND, -ex COMMAND
4211 Execute a single GDB CLI command. This may be
4212 specified multiple times and in conjunction
4213 with the --command (-x) option.
4215 * Deprecated commands removed
4217 The following commands, that were deprecated in 2000, have been
4221 set|show arm disassembly-flavor set|show arm disassembler
4222 othernames set arm disassembler
4223 set|show remotedebug set|show debug remote
4224 set|show archdebug set|show debug arch
4225 set|show eventdebug set|show debug event
4228 * New BSD user-level threads support
4230 It is now possible to debug programs using the user-level threads
4231 library on OpenBSD and FreeBSD. Currently supported (target)
4234 FreeBSD/amd64 x86_64-*-freebsd*
4235 FreeBSD/i386 i386-*-freebsd*
4236 OpenBSD/i386 i386-*-openbsd*
4238 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4239 are not yet supported.
4241 * New support for Matsushita MN10300 w/sim added
4242 (Work in progress). mn10300-elf.
4244 * REMOVED configurations and files
4246 VxWorks and the XDR protocol *-*-vxworks
4247 Motorola MCORE mcore-*-*
4248 National Semiconductor NS32000 ns32k-*-*
4250 * New "set print array-indexes" command
4252 After turning this setting "on", GDB prints the index of each element
4253 when displaying arrays. The default is "off" to preserve the previous
4256 * VAX floating point support
4258 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4260 * User-defined command support
4262 In addition to using $arg0..$arg9 for argument passing, it is now possible
4263 to use $argc to determine now many arguments have been passed. See the
4264 section on user-defined commands in the user manual for more information.
4266 *** Changes in GDB 6.3:
4268 * New command line option
4270 GDB now accepts -l followed by a number to set the timeout for remote
4273 * GDB works with GCC -feliminate-dwarf2-dups
4275 GDB now supports a more compact representation of DWARF-2 debug
4276 information using DW_FORM_ref_addr references. These are produced
4277 by GCC with the option -feliminate-dwarf2-dups and also by some
4278 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4279 to use -feliminate-dwarf2-dups.
4281 * Internationalization
4283 When supported by the host system, GDB will be built with
4284 internationalization (libintl). The task of marking up the sources is
4285 continued, we're looking forward to our first translation.
4289 Initial support for debugging programs compiled with the GNAT
4290 implementation of the Ada programming language has been integrated
4291 into GDB. In this release, support is limited to expression evaluation.
4293 * New native configurations
4295 GNU/Linux/m32r m32r-*-linux-gnu
4299 GDB's remote protocol now includes support for the 'p' packet. This
4300 packet is used to fetch individual registers from a remote inferior.
4302 * END-OF-LIFE registers[] compatibility module
4304 GDB's internal register infrastructure has been completely rewritten.
4305 The new infrastructure making possible the implementation of key new
4306 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4309 GDB 6.3 will be the last release to include the the registers[]
4310 compatibility module that allowed out-of-date configurations to
4311 continue to work. This change directly impacts the following
4321 powerpc bdm protocol
4323 Unless there is activity to revive these configurations, they will be
4324 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4326 * OBSOLETE configurations and files
4328 Configurations that have been declared obsolete in this release have
4329 been commented out. Unless there is activity to revive these
4330 configurations, the next release of GDB will have their sources
4331 permanently REMOVED.
4340 *** Changes in GDB 6.2.1:
4342 * MIPS `break main; run' gave an heuristic-fence-post warning
4344 When attempting to run even a simple program, a warning about
4345 heuristic-fence-post being hit would be reported. This problem has
4348 * MIPS IRIX 'long double' crashed GDB
4350 When examining a long double variable, GDB would get a segmentation
4351 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4352 IRIX long double values).
4356 A bug in the VAX stack code was causing problems with the "next"
4357 command. This problem has been fixed.
4359 *** Changes in GDB 6.2:
4361 * Fix for ``many threads''
4363 On GNU/Linux systems that use the NPTL threads library, a program
4364 rapidly creating and deleting threads would confuse GDB leading to the
4367 ptrace: No such process.
4368 thread_db_get_info: cannot get thread info: generic error
4370 This problem has been fixed.
4372 * "-async" and "-noasync" options removed.
4374 Support for the broken "-noasync" option has been removed (it caused
4377 * New ``start'' command.
4379 This command runs the program until the begining of the main procedure.
4381 * New BSD Kernel Data Access Library (libkvm) interface
4383 Using ``target kvm'' it is now possible to debug kernel core dumps and
4384 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4385 platforms. Currently supported (native-only) configurations are:
4387 FreeBSD/amd64 x86_64-*-freebsd*
4388 FreeBSD/i386 i?86-*-freebsd*
4389 NetBSD/i386 i?86-*-netbsd*
4390 NetBSD/m68k m68*-*-netbsd*
4391 NetBSD/sparc sparc-*-netbsd*
4392 OpenBSD/amd64 x86_64-*-openbsd*
4393 OpenBSD/i386 i?86-*-openbsd*
4394 OpenBSD/m68k m68*-openbsd*
4395 OpenBSD/sparc sparc-*-openbsd*
4397 * Signal trampoline code overhauled
4399 Many generic problems with GDB's signal handling code have been fixed.
4400 These include: backtraces through non-contiguous stacks; recognition
4401 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4402 call; backtrace through a signal trampoline; step into and out of
4403 signal handlers; and single-stepping in the signal trampoline.
4405 Please note that kernel bugs are a limiting factor here. These
4406 features have been shown to work on an s390 GNU/Linux system that
4407 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4409 * Cygwin support for DWARF 2 added.
4411 * New native configurations
4413 GNU/Linux/hppa hppa*-*-linux*
4414 OpenBSD/hppa hppa*-*-openbsd*
4415 OpenBSD/m68k m68*-*-openbsd*
4416 OpenBSD/m88k m88*-*-openbsd*
4417 OpenBSD/powerpc powerpc-*-openbsd*
4418 NetBSD/vax vax-*-netbsd*
4419 OpenBSD/vax vax-*-openbsd*
4421 * END-OF-LIFE frame compatibility module
4423 GDB's internal frame infrastructure has been completely rewritten.
4424 The new infrastructure making it possible to support key new features
4425 including DWARF 2 Call Frame Information. To aid in the task of
4426 migrating old configurations to this new infrastructure, a
4427 compatibility module, that allowed old configurations to continue to
4428 work, was also included.
4430 GDB 6.2 will be the last release to include this frame compatibility
4431 module. This change directly impacts the following configurations:
4441 Unless there is activity to revive these configurations, they will be
4442 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4444 * REMOVED configurations and files
4446 Sun 3, running SunOS 3 m68*-*-sunos3*
4447 Sun 3, running SunOS 4 m68*-*-sunos4*
4448 Sun 2, running SunOS 3 m68000-*-sunos3*
4449 Sun 2, running SunOS 4 m68000-*-sunos4*
4450 Motorola 680x0 running LynxOS m68*-*-lynxos*
4451 AT&T 3b1/Unix pc m68*-att-*
4452 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4453 decstation mips-dec-* mips-little-*
4454 riscos mips-*-riscos* mips-*-sysv*
4455 sonymips mips-sony-*
4456 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4458 *** Changes in GDB 6.1.1:
4460 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4462 The TUI (Text-mode User Interface) is now built as part of a default
4463 GDB configuration. It is enabled by either selecting the TUI with the
4464 command line option "-i=tui" or by running the separate "gdbtui"
4465 program. For more information on the TUI, see the manual "Debugging
4468 * Pending breakpoint support (also included in GDB 6.1)
4470 Support has been added to allow you to specify breakpoints in shared
4471 libraries that have not yet been loaded. If a breakpoint location
4472 cannot be found, and the "breakpoint pending" option is set to auto,
4473 GDB queries you if you wish to make the breakpoint pending on a future
4474 shared-library load. If and when GDB resolves the breakpoint symbol,
4475 the pending breakpoint is removed as one or more regular breakpoints
4478 Pending breakpoints are very useful for GCJ Java debugging.
4480 * Fixed ISO-C build problems
4482 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4483 non ISO-C code that stopped them being built using a more strict ISO-C
4484 compiler (e.g., IBM's C compiler).
4486 * Fixed build problem on IRIX 5
4488 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4489 wasn't able to compile compile on an IRIX 5 system.
4491 * Added execute permission to gdb/gdbserver/configure
4493 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4494 permission. This bug would cause configure to fail on a number of
4495 systems (Solaris, IRIX). Ref: server/519.
4497 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4499 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4500 has been updated to use constant array sizes.
4502 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4504 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4505 its generated DWARF Call Frame Info. This encoding was causing GDB to
4506 panic, that panic has been fixed. Ref: gdb/1628.
4508 * Fixed a problem when examining parameters in shared library code.
4510 When examining parameters in optimized shared library code generated
4511 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4512 not available''. GDB now correctly displays the variable's value.
4514 *** Changes in GDB 6.1:
4516 * Removed --with-mmalloc
4518 Support for the mmalloc memory manager has been removed, as it
4519 conflicted with the internal gdb byte cache.
4521 * Changes in AMD64 configurations
4523 The AMD64 target now includes the %cs and %ss registers. As a result
4524 the AMD64 remote protocol has changed; this affects the floating-point
4525 and SSE registers. If you rely on those registers for your debugging,
4526 you should upgrade gdbserver on the remote side.
4528 * Revised SPARC target
4530 The SPARC target has been completely revised, incorporating the
4531 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4532 support for LynxOS and SunOS 4 has been dropped. Calling functions
4533 from within GDB on operating systems with a non-executable stack
4534 (Solaris, OpenBSD) now works.
4538 GDB has a new C++ demangler which does a better job on the mangled
4539 names generated by current versions of g++. It also runs faster, so
4540 with this and other changes gdb should now start faster on large C++
4543 * DWARF 2 Location Expressions
4545 GDB support for location expressions has been extended to support function
4546 arguments and frame bases. Older versions of GDB could crash when they
4549 * C++ nested types and namespaces
4551 GDB's support for nested types and namespaces in C++ has been
4552 improved, especially if you use the DWARF 2 debugging format. (This
4553 is the default for recent versions of GCC on most platforms.)
4554 Specifically, if you have a class "Inner" defined within a class or
4555 namespace "Outer", then GDB realizes that the class's name is
4556 "Outer::Inner", not simply "Inner". This should greatly reduce the
4557 frequency of complaints about not finding RTTI symbols. In addition,
4558 if you are stopped at inside of a function defined within a namespace,
4559 GDB modifies its name lookup accordingly.
4561 * New native configurations
4563 NetBSD/amd64 x86_64-*-netbsd*
4564 OpenBSD/amd64 x86_64-*-openbsd*
4565 OpenBSD/alpha alpha*-*-openbsd*
4566 OpenBSD/sparc sparc-*-openbsd*
4567 OpenBSD/sparc64 sparc64-*-openbsd*
4569 * New debugging protocols
4571 M32R with SDI protocol m32r-*-elf*
4573 * "set prompt-escape-char" command deleted.
4575 The command "set prompt-escape-char" has been deleted. This command,
4576 and its very obscure effet on GDB's prompt, was never documented,
4577 tested, nor mentioned in the NEWS file.
4579 * OBSOLETE configurations and files
4581 Configurations that have been declared obsolete in this release have
4582 been commented out. Unless there is activity to revive these
4583 configurations, the next release of GDB will have their sources
4584 permanently REMOVED.
4586 Sun 3, running SunOS 3 m68*-*-sunos3*
4587 Sun 3, running SunOS 4 m68*-*-sunos4*
4588 Sun 2, running SunOS 3 m68000-*-sunos3*
4589 Sun 2, running SunOS 4 m68000-*-sunos4*
4590 Motorola 680x0 running LynxOS m68*-*-lynxos*
4591 AT&T 3b1/Unix pc m68*-att-*
4592 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4593 decstation mips-dec-* mips-little-*
4594 riscos mips-*-riscos* mips-*-sysv*
4595 sonymips mips-sony-*
4596 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4598 * REMOVED configurations and files
4600 SGI Irix-4.x mips-sgi-irix4 or iris4
4601 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4602 Z8000 simulator z8k-zilog-none or z8ksim
4603 Matsushita MN10200 w/simulator mn10200-*-*
4604 H8/500 simulator h8500-hitachi-hms or h8500hms
4605 HP/PA running BSD hppa*-*-bsd*
4606 HP/PA running OSF/1 hppa*-*-osf*
4607 HP/PA Pro target hppa*-*-pro*
4608 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4609 386BSD i[3456]86-*-bsd*
4610 Sequent family i[3456]86-sequent-sysv4*
4611 i[3456]86-sequent-sysv*
4612 i[3456]86-sequent-bsd*
4613 SPARC running LynxOS sparc-*-lynxos*
4614 SPARC running SunOS 4 sparc-*-sunos4*
4615 Tsqware Sparclet sparclet-*-*
4616 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4618 *** Changes in GDB 6.0:
4622 Support for debugging the Objective-C programming language has been
4623 integrated into GDB.
4625 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4627 DWARF 2's Call Frame Information makes available compiler generated
4628 information that more exactly describes the program's run-time stack.
4629 By using this information, GDB is able to provide more robust stack
4632 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4633 have been updated to use a new backtrace mechanism which includes
4634 DWARF 2 CFI support.
4638 GDB's remote protocol has been extended to include support for hosted
4639 file I/O (where the remote target uses GDB's file system). See GDB's
4640 remote protocol documentation for details.
4642 * All targets using the new architecture framework.
4644 All of GDB's targets have been updated to use the new internal
4645 architecture framework. The way is now open for future GDB releases
4646 to include cross-architecture native debugging support (i386 on amd64,
4649 * GNU/Linux's Thread Local Storage (TLS)
4651 GDB now includes support for for the GNU/Linux implementation of
4652 per-thread variables.
4654 * GNU/Linux's Native POSIX Thread Library (NPTL)
4656 GDB's thread code has been updated to work with either the new
4657 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4659 * Separate debug info.
4661 GDB, in conjunction with BINUTILS, now supports a mechanism for
4662 automatically loading debug information from a separate file. Instead
4663 of shipping full debug and non-debug versions of system libraries,
4664 system integrators can now instead ship just the stripped libraries
4665 and optional debug files.
4667 * DWARF 2 Location Expressions
4669 DWARF 2 Location Expressions allow the compiler to more completely
4670 describe the location of variables (even in optimized code) to the
4673 GDB now includes preliminary support for location expressions (support
4674 for DW_OP_piece is still missing).
4678 A number of long standing bugs that caused GDB to die while starting a
4679 Java application have been fixed. GDB's Java support is now
4680 considered "useable".
4682 * GNU/Linux support for fork, vfork, and exec.
4684 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4685 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4688 * GDB supports logging output to a file
4690 There are two new commands, "set logging" and "show logging", which can be
4691 used to capture GDB's output to a file.
4693 * The meaning of "detach" has changed for gdbserver
4695 The "detach" command will now resume the application, as documented. To
4696 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4699 * d10v, m68hc11 `regs' command deprecated
4701 The `info registers' command has been updated so that it displays the
4702 registers using a format identical to the old `regs' command.
4706 A new command, "maint set profile on/off", has been added. This command can
4707 be used to enable or disable profiling while running GDB, to profile a
4708 session or a set of commands. In addition there is a new configure switch,
4709 "--enable-profiling", which will cause GDB to be compiled with profiling
4710 data, for more informative profiling results.
4712 * Default MI syntax changed to "mi2".
4714 The default MI (machine interface) syntax, enabled by the command line
4715 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4716 "mi1", can be enabled by specifying the option "-i=mi1".
4718 Support for the original "mi0" syntax (included in GDB 5.0) has been
4721 Fix for gdb/192: removed extraneous space when displaying frame level.
4722 Fix for gdb/672: update changelist is now output in mi list format.
4723 Fix for gdb/702: a -var-assign that updates the value now shows up
4724 in a subsequent -var-update.
4726 * New native configurations.
4728 FreeBSD/amd64 x86_64-*-freebsd*
4730 * Multi-arched targets.
4732 HP/PA HPUX11 hppa*-*-hpux*
4733 Renesas M32R/D w/simulator m32r-*-elf*
4735 * OBSOLETE configurations and files
4737 Configurations that have been declared obsolete in this release have
4738 been commented out. Unless there is activity to revive these
4739 configurations, the next release of GDB will have their sources
4740 permanently REMOVED.
4742 Z8000 simulator z8k-zilog-none or z8ksim
4743 Matsushita MN10200 w/simulator mn10200-*-*
4744 H8/500 simulator h8500-hitachi-hms or h8500hms
4745 HP/PA running BSD hppa*-*-bsd*
4746 HP/PA running OSF/1 hppa*-*-osf*
4747 HP/PA Pro target hppa*-*-pro*
4748 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4749 Sequent family i[3456]86-sequent-sysv4*
4750 i[3456]86-sequent-sysv*
4751 i[3456]86-sequent-bsd*
4752 Tsqware Sparclet sparclet-*-*
4753 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4755 * REMOVED configurations and files
4758 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4759 IBM AIX PS/2 i[3456]86-*-aix
4760 i386 running Mach 3.0 i[3456]86-*-mach3*
4761 i386 running Mach i[3456]86-*-mach*
4762 i386 running OSF/1 i[3456]86-*osf1mk*
4763 HP/Apollo 68k Family m68*-apollo*-sysv*,
4765 m68*-hp-bsd*, m68*-hp-hpux*
4766 Argonaut Risc Chip (ARC) arc-*-*
4767 Mitsubishi D30V d30v-*-*
4768 Fujitsu FR30 fr30-*-elf*
4769 OS/9000 i[34]86-*-os9k
4770 I960 with MON960 i960-*-coff
4772 * MIPS $fp behavior changed
4774 The convenience variable $fp, for the MIPS, now consistently returns
4775 the address of the current frame's base. Previously, depending on the
4776 context, $fp could refer to either $sp or the current frame's base
4777 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4778 The GNU Source-Level Debugger''.
4780 *** Changes in GDB 5.3:
4782 * GNU/Linux shared library multi-threaded performance improved.
4784 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4785 `/proc', in preference to `ptrace' for memory reads. This may result
4786 in an improvement in the start-up time of multi-threaded, shared
4787 library applications when run under GDB. One GDB user writes: ``loads
4788 shared libs like mad''.
4790 * ``gdbserver'' now supports multi-threaded applications on some targets
4792 Support for debugging multi-threaded applications which use
4793 the GNU/Linux LinuxThreads package has been added for
4794 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4795 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4797 * GDB now supports C/C++ preprocessor macros.
4799 GDB now expands preprocessor macro invocations in C/C++ expressions,
4800 and provides various commands for showing macro definitions and how
4803 The new command `macro expand EXPRESSION' expands any macro
4804 invocations in expression, and shows the result.
4806 The new command `show macro MACRO-NAME' shows the definition of the
4807 macro named MACRO-NAME, and where it was defined.
4809 Most compilers don't include information about macros in the debugging
4810 information by default. In GCC 3.1, for example, you need to compile
4811 your program with the options `-gdwarf-2 -g3'. If the macro
4812 information is present in the executable, GDB will read it.
4814 * Multi-arched targets.
4816 DEC Alpha (partial) alpha*-*-*
4817 DEC VAX (partial) vax-*-*
4819 National Semiconductor NS32000 (partial) ns32k-*-*
4820 Motorola 68000 (partial) m68k-*-*
4821 Motorola MCORE mcore-*-*
4825 Fujitsu FRV architecture added by Red Hat frv*-*-*
4828 * New native configurations
4830 Alpha NetBSD alpha*-*-netbsd*
4831 SH NetBSD sh*-*-netbsdelf*
4832 MIPS NetBSD mips*-*-netbsd*
4833 UltraSPARC NetBSD sparc64-*-netbsd*
4835 * OBSOLETE configurations and files
4837 Configurations that have been declared obsolete in this release have
4838 been commented out. Unless there is activity to revive these
4839 configurations, the next release of GDB will have their sources
4840 permanently REMOVED.
4842 Mitsubishi D30V d30v-*-*
4843 OS/9000 i[34]86-*-os9k
4844 IBM AIX PS/2 i[3456]86-*-aix
4845 Fujitsu FR30 fr30-*-elf*
4846 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4847 Argonaut Risc Chip (ARC) arc-*-*
4848 i386 running Mach 3.0 i[3456]86-*-mach3*
4849 i386 running Mach i[3456]86-*-mach*
4850 i386 running OSF/1 i[3456]86-*osf1mk*
4851 HP/Apollo 68k Family m68*-apollo*-sysv*,
4853 m68*-hp-bsd*, m68*-hp-hpux*
4854 I960 with MON960 i960-*-coff
4856 * OBSOLETE languages
4858 CHILL, a Pascal like language used by telecommunications companies.
4860 * REMOVED configurations and files
4862 AMD 29k family via UDI a29k-amd-udi, udi29k
4863 A29K VxWorks a29k-*-vxworks
4864 AMD 29000 embedded, using EBMON a29k-none-none
4865 AMD 29000 embedded with COFF a29k-none-coff
4866 AMD 29000 embedded with a.out a29k-none-aout
4868 testsuite/gdb.hp/gdb.threads-hp/ directory
4870 * New command "set max-user-call-depth <nnn>"
4872 This command allows the user to limit the call depth of user-defined
4873 commands. The default is 1024.
4875 * Changes in FreeBSD/i386 native debugging.
4877 Support for the "generate-core-file" has been added.
4879 * New commands "dump", "append", and "restore".
4881 These commands allow data to be copied from target memory
4882 to a bfd-format or binary file (dump and append), and back
4883 from a file into memory (restore).
4885 * Improved "next/step" support on multi-processor Alpha Tru64.
4887 The previous single-step mechanism could cause unpredictable problems,
4888 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4889 of a software single-step mechanism prevents this.
4891 *** Changes in GDB 5.2.1:
4899 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4900 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4901 Fix, by Joel Brobecker imported from mainline.
4903 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4904 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4905 Fix, by Fred Fish, imported from mainline.
4907 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4908 Surprisingly enough, it works now.
4909 By Michal Ludvig, imported from mainline.
4911 i386 hardware watchpoint support:
4912 avoid misses on second run for some targets.
4913 By Pierre Muller, imported from mainline.
4915 *** Changes in GDB 5.2:
4917 * New command "set trust-readonly-sections on[off]".
4919 This command is a hint that tells gdb that read-only sections
4920 really are read-only (ie. that their contents will not change).
4921 In this mode, gdb will go to the object file rather than the
4922 target to read memory from read-only sections (such as ".text").
4923 This can be a significant performance improvement on some
4924 (notably embedded) targets.
4926 * New command "generate-core-file" (or "gcore").
4928 This new gdb command allows the user to drop a core file of the child
4929 process state at any time. So far it's been implemented only for
4930 GNU/Linux and Solaris, but should be relatively easily ported to other
4931 hosts. Argument is core file name (defaults to core.<pid>).
4933 * New command line option
4935 GDB now accepts --pid or -p followed by a process id.
4937 * Change in command line behavior -- corefiles vs. process ids.
4939 There is a subtle behavior in the way in which GDB handles
4940 command line arguments. The first non-flag argument is always
4941 a program to debug, but the second non-flag argument may either
4942 be a corefile or a process id. Previously, GDB would attempt to
4943 open the second argument as a corefile, and if that failed, would
4944 issue a superfluous error message and then attempt to attach it as
4945 a process. Now, if the second argument begins with a non-digit,
4946 it will be treated as a corefile. If it begins with a digit,
4947 GDB will attempt to attach it as a process, and if no such process
4948 is found, will then attempt to open it as a corefile.
4950 * Changes in ARM configurations.
4952 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4953 configuration is fully multi-arch.
4955 * New native configurations
4957 ARM NetBSD arm*-*-netbsd*
4958 x86 OpenBSD i[3456]86-*-openbsd*
4959 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4960 Sparc64 running FreeBSD sparc64-*-freebsd*
4964 Sanyo XStormy16 xstormy16-elf
4966 * OBSOLETE configurations and files
4968 Configurations that have been declared obsolete in this release have
4969 been commented out. Unless there is activity to revive these
4970 configurations, the next release of GDB will have their sources
4971 permanently REMOVED.
4973 AMD 29k family via UDI a29k-amd-udi, udi29k
4974 A29K VxWorks a29k-*-vxworks
4975 AMD 29000 embedded, using EBMON a29k-none-none
4976 AMD 29000 embedded with COFF a29k-none-coff
4977 AMD 29000 embedded with a.out a29k-none-aout
4979 testsuite/gdb.hp/gdb.threads-hp/ directory
4981 * REMOVED configurations and files
4983 TI TMS320C80 tic80-*-*
4985 PowerPC Solaris powerpcle-*-solaris*
4986 PowerPC Windows NT powerpcle-*-cygwin32
4987 PowerPC Netware powerpc-*-netware*
4988 Harris/CXUX m88k m88*-harris-cxux*
4989 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4990 ns32k-utek-sysv* ns32k-utek-*
4991 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4992 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4993 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4994 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4995 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4997 * Changes to command line processing
4999 The new `--args' feature can be used to specify command-line arguments
5000 for the inferior from gdb's command line.
5002 * Changes to key bindings
5004 There is a new `operate-and-get-next' function bound to `C-o'.
5006 *** Changes in GDB 5.1.1
5008 Fix compile problem on DJGPP.
5010 Fix a problem with floating-point registers on the i386 being
5013 Fix to stop GDB crashing on .debug_str debug info.
5015 Numerous documentation fixes.
5017 Numerous testsuite fixes.
5019 *** Changes in GDB 5.1:
5021 * New native configurations
5023 Alpha FreeBSD alpha*-*-freebsd*
5024 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
5025 MIPS GNU/Linux mips*-*-linux*
5026 MIPS SGI Irix 6.x mips*-sgi-irix6*
5027 ia64 AIX ia64-*-aix*
5028 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
5032 Motorola 68HC11 and 68HC12 m68hc11-elf
5034 UltraSparc running GNU/Linux sparc64-*-linux*
5036 * OBSOLETE configurations and files
5038 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
5039 Harris/CXUX m88k m88*-harris-cxux*
5040 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5041 ns32k-utek-sysv* ns32k-utek-*
5042 TI TMS320C80 tic80-*-*
5044 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5045 PowerPC Solaris powerpcle-*-solaris*
5046 PowerPC Windows NT powerpcle-*-cygwin32
5047 PowerPC Netware powerpc-*-netware*
5048 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5049 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5050 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5051 Apple Macintosh (MPW) host N/A
5053 stuff.c (Program to stuff files into a specially prepared space in kdb)
5054 kdb-start.c (Main loop for the standalone kernel debugger)
5056 Configurations that have been declared obsolete in this release have
5057 been commented out. Unless there is activity to revive these
5058 configurations, the next release of GDB will have their sources
5059 permanently REMOVED.
5061 * REMOVED configurations and files
5063 Altos 3068 m68*-altos-*
5064 Convex c1-*-*, c2-*-*
5066 ARM RISCix arm-*-* (as host)
5070 * GDB has been converted to ISO C.
5072 GDB's source code has been converted to ISO C. In particular, the
5073 sources are fully protoized, and rely on standard headers being
5078 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
5080 * The MI enabled by default.
5082 The new machine oriented interface (MI) introduced in GDB 5.0 has been
5083 revised and enabled by default. Packages which use GDB as a debugging
5084 engine behind a UI or another front end are encouraged to switch to
5085 using the GDB/MI interface, instead of the old annotations interface
5086 which is now deprecated.
5088 * Support for debugging Pascal programs.
5090 GDB now includes support for debugging Pascal programs. The following
5091 main features are supported:
5093 - Pascal-specific data types such as sets;
5095 - automatic recognition of Pascal sources based on file-name
5098 - Pascal-style display of data types, variables, and functions;
5100 - a Pascal expression parser.
5102 However, some important features are not yet supported.
5104 - Pascal string operations are not supported at all;
5106 - there are some problems with boolean types;
5108 - Pascal type hexadecimal constants are not supported
5109 because they conflict with the internal variables format;
5111 - support for Pascal objects and classes is not full yet;
5113 - unlike Pascal, GDB is case-sensitive for symbol names.
5115 * Changes in completion.
5117 Commands such as `shell', `run' and `set args', which pass arguments
5118 to inferior programs, now complete on file names, similar to what
5119 users expect at the shell prompt.
5121 Commands which accept locations, such as `disassemble', `print',
5122 `breakpoint', `until', etc. now complete on filenames as well as
5123 program symbols. Thus, if you type "break foob TAB", and the source
5124 files linked into the programs include `foobar.c', that file name will
5125 be one of the candidates for completion. However, file names are not
5126 considered for completion after you typed a colon that delimits a file
5127 name from a name of a function in that file, as in "break foo.c:bar".
5129 `set demangle-style' completes on available demangling styles.
5131 * New platform-independent commands:
5133 It is now possible to define a post-hook for a command as well as a
5134 hook that runs before the command. For more details, see the
5135 documentation of `hookpost' in the GDB manual.
5137 * Changes in GNU/Linux native debugging.
5139 Support for debugging multi-threaded programs has been completely
5140 revised for all platforms except m68k and sparc. You can now debug as
5141 many threads as your system allows you to have.
5143 Attach/detach is supported for multi-threaded programs.
5145 Support for SSE registers was added for x86. This doesn't work for
5146 multi-threaded programs though.
5148 * Changes in MIPS configurations.
5150 Multi-arch support is enabled for all MIPS configurations.
5152 GDB can now be built as native debugger on SGI Irix 6.x systems for
5153 debugging n32 executables. (Debugging 64-bit executables is not yet
5156 * Unified support for hardware watchpoints in all x86 configurations.
5158 Most (if not all) native x86 configurations support hardware-assisted
5159 breakpoints and watchpoints in a unified manner. This support
5160 implements debug register sharing between watchpoints, which allows to
5161 put a virtually infinite number of watchpoints on the same address,
5162 and also supports watching regions up to 16 bytes with several debug
5165 The new maintenance command `maintenance show-debug-regs' toggles
5166 debugging print-outs in functions that insert, remove, and test
5167 watchpoints and hardware breakpoints.
5169 * Changes in the DJGPP native configuration.
5171 New command ``info dos sysinfo'' displays assorted information about
5172 the CPU, OS, memory, and DPMI server.
5174 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
5175 display information about segment descriptors stored in GDT, LDT, and
5178 New commands ``info dos pde'' and ``info dos pte'' display entries
5179 from Page Directory and Page Tables (for now works with CWSDPMI only).
5180 New command ``info dos address-pte'' displays the Page Table entry for
5181 a given linear address.
5183 GDB can now pass command lines longer than 126 characters to the
5184 program being debugged (requires an update to the libdbg.a library
5185 which is part of the DJGPP development kit).
5187 DWARF2 debug info is now supported.
5189 It is now possible to `step' and `next' through calls to `longjmp'.
5191 * Changes in documentation.
5193 All GDB documentation was converted to GFDL, the GNU Free
5194 Documentation License.
5196 Tracepoints-related commands are now fully documented in the GDB
5199 TUI, the Text-mode User Interface, is now documented in the manual.
5201 Tracepoints-related commands are now fully documented in the GDB
5204 The "GDB Internals" manual now has an index. It also includes
5205 documentation of `ui_out' functions, GDB coding standards, x86
5206 hardware watchpoints, and memory region attributes.
5208 * GDB's version number moved to ``version.in''
5210 The Makefile variable VERSION has been replaced by the file
5211 ``version.in''. People creating GDB distributions should update the
5212 contents of this file.
5216 GUD support is now a standard part of the EMACS distribution.
5218 *** Changes in GDB 5.0:
5220 * Improved support for debugging FP programs on x86 targets
5222 Unified and much-improved support for debugging floating-point
5223 programs on all x86 targets. In particular, ``info float'' now
5224 displays the FP registers in the same format on all x86 targets, with
5225 greater level of detail.
5227 * Improvements and bugfixes in hardware-assisted watchpoints
5229 It is now possible to watch array elements, struct members, and
5230 bitfields with hardware-assisted watchpoints. Data-read watchpoints
5231 on x86 targets no longer erroneously trigger when the address is
5234 * Improvements in the native DJGPP version of GDB
5236 The distribution now includes all the scripts and auxiliary files
5237 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5238 machines ``out of the box''.
5240 The DJGPP version can now debug programs that use signals. It is
5241 possible to catch signals that happened in the debuggee, deliver
5242 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5243 would kill the program being debugged.) Programs that hook hardware
5244 interrupts (keyboard, timer, etc.) can also be debugged.
5246 It is now possible to debug DJGPP programs that redirect their
5247 standard handles or switch them to raw (as opposed to cooked) mode, or
5248 even close them. The command ``run < foo > bar'' works as expected,
5249 and ``info terminal'' reports useful information about the debuggee's
5250 terminal, including raw/cooked mode, redirection, etc.
5252 The DJGPP version now uses termios functions for console I/O, which
5253 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5256 DOS-style file names with drive letters are now fully supported by
5259 It is now possible to debug DJGPP programs that switch their working
5260 directory. It is also possible to rerun the debuggee any number of
5261 times without restarting GDB; thus, you can use the same setup,
5262 breakpoints, etc. for many debugging sessions.
5264 * New native configurations
5266 ARM GNU/Linux arm*-*-linux*
5267 PowerPC GNU/Linux powerpc-*-linux*
5271 Motorola MCore mcore-*-*
5272 x86 VxWorks i[3456]86-*-vxworks*
5273 PowerPC VxWorks powerpc-*-vxworks*
5274 TI TMS320C80 tic80-*-*
5276 * OBSOLETE configurations
5278 Altos 3068 m68*-altos-*
5279 Convex c1-*-*, c2-*-*
5281 ARM RISCix arm-*-* (as host)
5284 Configurations that have been declared obsolete will be commented out,
5285 but the code will be left in place. If there is no activity to revive
5286 these configurations before the next release of GDB, the sources will
5287 be permanently REMOVED.
5289 * Gould support removed
5291 Support for the Gould PowerNode and NP1 has been removed.
5293 * New features for SVR4
5295 On SVR4 native platforms (such as Solaris), if you attach to a process
5296 without first loading a symbol file, GDB will now attempt to locate and
5297 load symbols from the running process's executable file.
5299 * Many C++ enhancements
5301 C++ support has been greatly improved. Overload resolution now works properly
5302 in almost all cases. RTTI support is on the way.
5304 * Remote targets can connect to a sub-program
5306 A popen(3) style serial-device has been added. This device starts a
5307 sub-process (such as a stand-alone simulator) and then communicates
5308 with that. The sub-program to run is specified using the syntax
5309 ``|<program> <args>'' vis:
5311 (gdb) set remotedebug 1
5312 (gdb) target extended-remote |mn10300-elf-sim program-args
5314 * MIPS 64 remote protocol
5316 A long standing bug in the mips64 remote protocol where by GDB
5317 expected certain 32 bit registers (ex SR) to be transfered as 32
5318 instead of 64 bits has been fixed.
5320 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5321 added to provide backward compatibility with older versions of GDB.
5323 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5325 The command ``set remotebinarydownload'' command has been replaced by
5326 ``set remote X-packet''. Other commands in ``set remote'' family
5327 include ``set remote P-packet''.
5329 * Breakpoint commands accept ranges.
5331 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5332 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5333 ``tracepoint passcount'' also accepts a range of tracepoints.
5335 * ``apropos'' command added.
5337 The ``apropos'' command searches through command names and
5338 documentation strings, printing out matches, making it much easier to
5339 try to find a command that does what you are looking for.
5343 A new machine oriented interface (MI) has been added to GDB. This
5344 interface is designed for debug environments running GDB as a separate
5345 process. This is part of the long term libGDB project. See the
5346 "GDB/MI" chapter of the GDB manual for further information. It can be
5347 enabled by configuring with:
5349 .../configure --enable-gdbmi
5351 *** Changes in GDB-4.18:
5353 * New native configurations
5355 HP-UX 10.20 hppa*-*-hpux10.20
5356 HP-UX 11.x hppa*-*-hpux11.0*
5357 M68K GNU/Linux m68*-*-linux*
5361 Fujitsu FR30 fr30-*-elf*
5362 Intel StrongARM strongarm-*-*
5363 Mitsubishi D30V d30v-*-*
5365 * OBSOLETE configurations
5367 Gould PowerNode, NP1 np1-*-*, pn-*-*
5369 Configurations that have been declared obsolete will be commented out,
5370 but the code will be left in place. If there is no activity to revive
5371 these configurations before the next release of GDB, the sources will
5372 be permanently REMOVED.
5376 As a compatibility experiment, GDB's source files buildsym.h and
5377 buildsym.c have been converted to pure standard C, no longer
5378 containing any K&R compatibility code. We believe that all systems in
5379 use today either come with a standard C compiler, or have a GCC port
5380 available. If this is not true, please report the affected
5381 configuration to bug-gdb@gnu.org immediately. See the README file for
5382 information about getting a standard C compiler if you don't have one
5387 GDB now uses readline 2.2.
5389 * set extension-language
5391 You can now control the mapping between filename extensions and source
5392 languages by using the `set extension-language' command. For instance,
5393 you can ask GDB to treat .c files as C++ by saying
5394 set extension-language .c c++
5395 The command `info extensions' lists all of the recognized extensions
5396 and their associated languages.
5398 * Setting processor type for PowerPC and RS/6000
5400 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5401 you can use the `set processor' command to specify what variant of the
5402 PowerPC family you are debugging. The command
5406 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5407 following PowerPC and RS6000 variants:
5409 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5410 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5412 403GC IBM PowerPC 403GC
5413 505 Motorola PowerPC 505
5414 860 Motorola PowerPC 860 or 850
5415 601 Motorola PowerPC 601
5416 602 Motorola PowerPC 602
5417 603 Motorola/IBM PowerPC 603 or 603e
5418 604 Motorola PowerPC 604 or 604e
5419 750 Motorola/IBM PowerPC 750 or 750
5421 At the moment, this command just tells GDB what to name the
5422 special-purpose processor registers. Since almost all the affected
5423 registers are inaccessible to user-level programs, this command is
5424 only useful for remote debugging in its present form.
5428 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5429 more extensive support for HP-UX. Added features include shared
5430 library support, kernel threads and hardware watchpoints for 11.00,
5431 support for HP's ANSI C and C++ compilers, and a compatibility mode
5432 for xdb and dbx commands.
5436 HP's donation includes the new concept of catchpoints, which is a
5437 generalization of the old catch command. On HP-UX, it is now possible
5438 to catch exec, fork, and vfork, as well as library loading.
5440 This means that the existing catch command has changed; its first
5441 argument now specifies the type of catch to be set up. See the
5442 output of "help catch" for a list of catchpoint types.
5444 * Debugging across forks
5446 On HP-UX, you can choose which process to debug when a fork() happens
5451 HP has donated a curses-based terminal user interface (TUI). To get
5452 it, build with --enable-tui. Although this can be enabled for any
5453 configuration, at present it only works for native HP debugging.
5455 * GDB remote protocol additions
5457 A new protocol packet 'X' that writes binary data is now available.
5458 Default behavior is to try 'X', then drop back to 'M' if the stub
5459 fails to respond. The settable variable `remotebinarydownload'
5460 allows explicit control over the use of 'X'.
5462 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5463 full 64-bit address. The command
5465 set remoteaddresssize 32
5467 can be used to revert to the old behaviour. For existing remote stubs
5468 the change should not be noticed, as the additional address information
5471 In order to assist in debugging stubs, you may use the maintenance
5472 command `packet' to send any text string to the stub. For instance,
5474 maint packet heythere
5476 sends the packet "$heythere#<checksum>". Note that it is very easy to
5477 disrupt a debugging session by sending the wrong packet at the wrong
5480 The compare-sections command allows you to compare section data on the
5481 target to what is in the executable file without uploading or
5482 downloading, by comparing CRC checksums.
5484 * Tracing can collect general expressions
5486 You may now collect general expressions at tracepoints. This requires
5487 further additions to the target-side stub; see tracepoint.c and
5488 doc/agentexpr.texi for further details.
5490 * mask-address variable for Mips
5492 For Mips targets, you may control the zeroing of the upper 32 bits of
5493 a 64-bit address by entering `set mask-address on'. This is mainly
5494 of interest to users of embedded R4xxx and R5xxx processors.
5496 * Higher serial baud rates
5498 GDB's serial code now allows you to specify baud rates 57600, 115200,
5499 230400, and 460800 baud. (Note that your host system may not be able
5500 to achieve all of these rates.)
5504 The i960 configuration now includes an initial implementation of a
5505 builtin simulator, contributed by Jim Wilson.
5508 *** Changes in GDB-4.17:
5510 * New native configurations
5512 Alpha GNU/Linux alpha*-*-linux*
5513 Unixware 2.x i[3456]86-unixware2*
5514 Irix 6.x mips*-sgi-irix6*
5515 PowerPC GNU/Linux powerpc-*-linux*
5516 PowerPC Solaris powerpcle-*-solaris*
5517 Sparc GNU/Linux sparc-*-linux*
5518 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5522 Argonaut Risc Chip (ARC) arc-*-*
5523 Hitachi H8/300S h8300*-*-*
5524 Matsushita MN10200 w/simulator mn10200-*-*
5525 Matsushita MN10300 w/simulator mn10300-*-*
5526 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5527 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5528 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5529 Mitsubishi D10V w/simulator d10v-*-*
5530 Mitsubishi M32R/D w/simulator m32r-*-elf*
5531 Tsqware Sparclet sparclet-*-*
5532 NEC V850 w/simulator v850-*-*
5534 * New debugging protocols
5536 ARM with RDI protocol arm*-*-*
5537 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5538 DDB and LSI variants of PMON protocol mips*-*-*
5539 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5540 PowerPC with SDS protocol powerpc{,le}-*-eabi
5541 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5545 All configurations can now understand and use the DWARF 2 debugging
5546 format. The choice is automatic, if the symbol file contains DWARF 2
5551 GDB now includes basic Java language support. This support is
5552 only useful with Java compilers that produce native machine code.
5554 * solib-absolute-prefix and solib-search-path
5556 For SunOS and SVR4 shared libraries, you may now set the prefix for
5557 loading absolute shared library symbol files, and the search path for
5558 locating non-absolute shared library symbol files.
5560 * Live range splitting
5562 GDB can now effectively debug code for which GCC has performed live
5563 range splitting as part of its optimization. See gdb/doc/LRS for
5564 more details on the expected format of the stabs information.
5568 GDB's support for the GNU Hurd, including thread debugging, has been
5569 updated to work with current versions of the Hurd.
5573 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5574 instruction set. ARM GDB automatically detects when Thumb
5575 instructions are in use, and adjusts disassembly and backtracing
5580 GDB's MIPS target configurations now handle the MIP16 16-bit
5585 GDB now includes support for overlays; if an executable has been
5586 linked such that multiple sections are based at the same address, GDB
5587 will decide which section to use for symbolic info. You can choose to
5588 control the decision manually, using overlay commands, or implement
5589 additional target-side support and use "overlay load-target" to bring
5590 in the overlay mapping. Do "help overlay" for more detail.
5594 The command "info symbol <address>" displays information about
5595 the symbol at the specified address.
5599 The standard remote protocol now includes an extension that allows
5600 asynchronous collection and display of trace data. This requires
5601 extensive support in the target-side debugging stub. Tracing mode
5602 includes a new interaction mode in GDB and new commands: see the
5603 file tracepoint.c for more details.
5607 Configurations for embedded MIPS now include a simulator contributed
5608 by Cygnus Solutions. The simulator supports the instruction sets
5609 of most MIPS variants.
5613 Sparc configurations may now include the ERC32 simulator contributed
5614 by the European Space Agency. The simulator is not built into
5615 Sparc targets by default; configure with --enable-sim to include it.
5619 For target configurations that may include multiple variants of a
5620 basic architecture (such as MIPS and SH), you may now set the
5621 architecture explicitly. "set arch" sets, "info arch" lists
5622 the possible architectures.
5624 *** Changes in GDB-4.16:
5626 * New native configurations
5628 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5629 M68K NetBSD m68k-*-netbsd*
5630 PowerPC AIX 4.x powerpc-*-aix*
5631 PowerPC MacOS powerpc-*-macos*
5632 PowerPC Windows NT powerpcle-*-cygwin32
5633 RS/6000 AIX 4.x rs6000-*-aix4*
5637 ARM with RDP protocol arm-*-*
5638 I960 with MON960 i960-*-coff
5639 MIPS VxWorks mips*-*-vxworks*
5640 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5641 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5643 Matra Sparclet sparclet-*-*
5647 The powerpc-eabi configuration now includes the PSIM simulator,
5648 contributed by Andrew Cagney, with assistance from Mike Meissner.
5649 PSIM is a very elaborate model of the PowerPC, including not only
5650 basic instruction set execution, but also details of execution unit
5651 performance and I/O hardware. See sim/ppc/README for more details.
5655 GDB now works with Solaris 2.5.
5657 * Windows 95/NT native
5659 GDB will now work as a native debugger on Windows 95 and Windows NT.
5660 To build it from source, you must use the "gnu-win32" environment,
5661 which uses a DLL to emulate enough of Unix to run the GNU tools.
5662 Further information, binaries, and sources are available at
5663 ftp.cygnus.com, under pub/gnu-win32.
5665 * dont-repeat command
5667 If a user-defined command includes the command `dont-repeat', then the
5668 command will not be repeated if the user just types return. This is
5669 useful if the command is time-consuming to run, so that accidental
5670 extra keystrokes don't run the same command many times.
5672 * Send break instead of ^C
5674 The standard remote protocol now includes an option to send a break
5675 rather than a ^C to the target in order to interrupt it. By default,
5676 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5678 * Remote protocol timeout
5680 The standard remote protocol includes a new variable `remotetimeout'
5681 that allows you to set the number of seconds before GDB gives up trying
5682 to read from the target. The default value is 2.
5684 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5686 By default GDB will automatically keep track of objects as they are
5687 loaded and unloaded by the dynamic linker. By using the command `set
5688 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5689 when shared library events occur, thus allowing you to set breakpoints
5690 in shared libraries which are explicitly loaded by the inferior.
5692 Note this feature does not work on hpux8. On hpux9 you must link
5693 /usr/lib/end.o into your program. This feature should work
5694 automatically on hpux10.
5696 * Irix 5.x hardware watchpoint support
5698 Irix 5 configurations now support the use of hardware watchpoints.
5700 * Mips protocol "SYN garbage limit"
5702 When debugging a Mips target using the `target mips' protocol, you
5703 may set the number of characters that GDB will ignore by setting
5704 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5705 every character. The default value is 1050.
5707 * Recording and replaying remote debug sessions
5709 If you set `remotelogfile' to the name of a file, gdb will write to it
5710 a recording of a remote debug session. This recording may then be
5711 replayed back to gdb using "gdbreplay". See gdbserver/README for
5712 details. This is useful when you have a problem with GDB while doing
5713 remote debugging; you can make a recording of the session and send it
5714 to someone else, who can then recreate the problem.
5716 * Speedups for remote debugging
5718 GDB includes speedups for downloading and stepping MIPS systems using
5719 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5720 and more efficient S-record downloading.
5722 * Memory use reductions and statistics collection
5724 GDB now uses less memory and reports statistics about memory usage.
5725 Try the `maint print statistics' command, for example.
5727 *** Changes in GDB-4.15:
5729 * Psymtabs for XCOFF
5731 The symbol reader for AIX GDB now uses partial symbol tables. This
5732 can greatly improve startup time, especially for large executables.
5734 * Remote targets use caching
5736 Remote targets now use a data cache to speed up communication with the
5737 remote side. The data cache could lead to incorrect results because
5738 it doesn't know about volatile variables, thus making it impossible to
5739 debug targets which use memory mapped I/O devices. `set remotecache
5740 off' turns the the data cache off.
5742 * Remote targets may have threads
5744 The standard remote protocol now includes support for multiple threads
5745 in the target system, using new protocol commands 'H' and 'T'. See
5746 gdb/remote.c for details.
5750 If GDB is configured with `--enable-netrom', then it will include
5751 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5752 acts as though it is a bank of ROM on the target board, but you can
5753 write into it over the network. GDB's support consists only of
5754 support for fast loading into the emulated ROM; to debug, you must use
5755 another protocol, such as standard remote protocol. The usual
5756 sequence is something like
5758 target nrom <netrom-hostname>
5760 target remote <netrom-hostname>:1235
5764 GDB now includes support for the Apple Macintosh, as a host only. It
5765 may be run as either an MPW tool or as a standalone application, and
5766 it can debug through the serial port. All the usual GDB commands are
5767 available, but to the target command, you must supply "serial" as the
5768 device type instead of "/dev/ttyXX". See mpw-README in the main
5769 directory for more information on how to build. The MPW configuration
5770 scripts */mpw-config.in support only a few targets, and only the
5771 mips-idt-ecoff target has been tested.
5775 GDB configuration now uses autoconf. This is not user-visible,
5776 but does simplify configuration and building.
5780 GDB now supports hpux10.
5782 *** Changes in GDB-4.14:
5784 * New native configurations
5786 x86 FreeBSD i[345]86-*-freebsd
5787 x86 NetBSD i[345]86-*-netbsd
5788 NS32k NetBSD ns32k-*-netbsd
5789 Sparc NetBSD sparc-*-netbsd
5793 A29K VxWorks a29k-*-vxworks
5794 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5795 CPU32 EST-300 emulator m68*-*-est*
5796 PowerPC ELF powerpc-*-elf
5799 * Alpha OSF/1 support for procfs
5801 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5802 possible to attach to running processes. As the mounting of the /proc
5803 filesystem is optional on the Alpha, GDB automatically determines
5804 the availability of /proc during startup. This can lead to problems
5805 if /proc is unmounted after GDB has been started.
5807 * Arguments to user-defined commands
5809 User commands may accept up to 10 arguments separated by whitespace.
5810 Arguments are accessed within the user command via $arg0..$arg9. A
5813 print $arg0 + $arg1 + $arg2
5815 To execute the command use:
5818 Defines the command "adder" which prints the sum of its three arguments.
5819 Note the arguments are text substitutions, so they may reference variables,
5820 use complex expressions, or even perform inferior function calls.
5822 * New `if' and `while' commands
5824 This makes it possible to write more sophisticated user-defined
5825 commands. Both commands take a single argument, which is the
5826 expression to evaluate, and must be followed by the commands to
5827 execute, one per line, if the expression is nonzero, the list being
5828 terminated by the word `end'. The `if' command list may include an
5829 `else' word, which causes the following commands to be executed only
5830 if the expression is zero.
5832 * Fortran source language mode
5834 GDB now includes partial support for Fortran 77. It will recognize
5835 Fortran programs and can evaluate a subset of Fortran expressions, but
5836 variables and functions may not be handled correctly. GDB will work
5837 with G77, but does not yet know much about symbols emitted by other
5840 * Better HPUX support
5842 Most debugging facilities now work on dynamic executables for HPPAs
5843 running hpux9 or later. You can attach to running dynamically linked
5844 processes, but by default the dynamic libraries will be read-only, so
5845 for instance you won't be able to put breakpoints in them. To change
5846 that behavior do the following before running the program:
5852 This will cause the libraries to be mapped private and read-write.
5853 To revert to the normal behavior, do this:
5859 You cannot set breakpoints or examine data in the library until after
5860 the library is loaded if the function/data symbols do not have
5863 GDB can now also read debug symbols produced by the HP C compiler on
5864 HPPAs (sorry, no C++, Fortran or 68k support).
5866 * Target byte order now dynamically selectable
5868 You can choose which byte order to use with a target system, via the
5869 commands "set endian big" and "set endian little", and you can see the
5870 current setting by using "show endian". You can also give the command
5871 "set endian auto", in which case GDB will use the byte order
5872 associated with the executable. Currently, only embedded MIPS
5873 configurations support dynamic selection of target byte order.
5875 * New DOS host serial code
5877 This version uses DPMI interrupts to handle buffered I/O, so you
5878 no longer need to run asynctsr when debugging boards connected to
5881 *** Changes in GDB-4.13:
5883 * New "complete" command
5885 This lists all the possible completions for the rest of the line, if it
5886 were to be given as a command itself. This is intended for use by emacs.
5888 * Trailing space optional in prompt
5890 "set prompt" no longer adds a space for you after the prompt you set. This
5891 allows you to set a prompt which ends in a space or one that does not.
5893 * Breakpoint hit counts
5895 "info break" now displays a count of the number of times the breakpoint
5896 has been hit. This is especially useful in conjunction with "ignore"; you
5897 can ignore a large number of breakpoint hits, look at the breakpoint info
5898 to see how many times the breakpoint was hit, then run again, ignoring one
5899 less than that number, and this will get you quickly to the last hit of
5902 * Ability to stop printing at NULL character
5904 "set print null-stop" will cause GDB to stop printing the characters of
5905 an array when the first NULL is encountered. This is useful when large
5906 arrays actually contain only short strings.
5908 * Shared library breakpoints
5910 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5911 breakpoints in shared libraries before the executable is run.
5913 * Hardware watchpoints
5915 There is a new hardware breakpoint for the watch command for sparclite
5916 targets. See gdb/sparclite/hw_breakpoint.note.
5918 Hardware watchpoints are also now supported under GNU/Linux.
5922 Annotations have been added. These are for use with graphical interfaces,
5923 and are still experimental. Currently only gdba.el uses these.
5925 * Improved Irix 5 support
5927 GDB now works properly with Irix 5.2.
5929 * Improved HPPA support
5931 GDB now works properly with the latest GCC and GAS.
5933 * New native configurations
5935 Sequent PTX4 i[34]86-sequent-ptx4
5936 HPPA running OSF/1 hppa*-*-osf*
5937 Atari TT running SVR4 m68*-*-sysv4*
5938 RS/6000 LynxOS rs6000-*-lynxos*
5942 OS/9000 i[34]86-*-os9k
5943 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5946 * Hitachi SH7000 and E7000-PC ICE support
5948 There is now support for communicating with the Hitachi E7000-PC ICE.
5949 This is available automatically when GDB is configured for the SH.
5953 As usual, a variety of small fixes and improvements, both generic
5954 and configuration-specific. See the ChangeLog for more detail.
5956 *** Changes in GDB-4.12:
5958 * Irix 5 is now supported
5962 GDB-4.12 on the HPPA has a number of changes which make it unable
5963 to debug the output from the currently released versions of GCC and
5964 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5965 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5966 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5969 *** Changes in GDB-4.11:
5971 * User visible changes:
5975 The "set remotedebug" option is now consistent between the mips remote
5976 target, remote targets using the gdb-specific protocol, UDI (AMD's
5977 debug protocol for the 29k) and the 88k bug monitor. It is now an
5978 integer specifying a debug level (normally 0 or 1, but 2 means more
5979 debugging info for the mips target).
5981 * DEC Alpha native support
5983 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5984 debug info, but GDB works fairly well with the DEC compiler and should
5985 work with a future GCC release. See the README file for a few
5986 Alpha-specific notes.
5988 * Preliminary thread implementation
5990 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5992 * LynxOS native and target support for 386
5994 This release has been hosted on LynxOS 2.2, and also can be configured
5995 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5998 * Improvements in C++ mangling/demangling.
6000 This release has much better g++ debugging, specifically in name
6001 mangling/demangling, virtual function calls, print virtual table,
6002 call methods, ...etc.
6004 *** Changes in GDB-4.10:
6006 * User visible changes:
6008 Remote debugging using the GDB-specific (`target remote') protocol now
6009 supports the `load' command. This is only useful if you have some
6010 other way of getting the stub to the target system, and you can put it
6011 somewhere in memory where it won't get clobbered by the download.
6013 Filename completion now works.
6015 When run under emacs mode, the "info line" command now causes the
6016 arrow to point to the line specified. Also, "info line" prints
6017 addresses in symbolic form (as well as hex).
6019 All vxworks based targets now support a user settable option, called
6020 vxworks-timeout. This option represents the number of seconds gdb
6021 should wait for responses to rpc's. You might want to use this if
6022 your vxworks target is, perhaps, a slow software simulator or happens
6023 to be on the far side of a thin network line.
6027 This release contains support for using a DEC alpha as a GDB host for
6028 cross debugging. Native alpha debugging is not supported yet.
6031 *** Changes in GDB-4.9:
6035 This is the first GDB release which is accompanied by a matching testsuite.
6036 The testsuite requires installation of dejagnu, which should be available
6037 via ftp from most sites that carry GNU software.
6041 'Cfront' style demangling has had its name changed to 'ARM' style, to
6042 emphasize that it was written from the specifications in the C++ Annotated
6043 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
6044 disclaimers, it still generated too much confusion with users attempting to
6045 use gdb with AT&T cfront.
6049 GDB now uses a standard remote interface to a simulator library.
6050 So far, the library contains simulators for the Zilog Z8001/2, the
6051 Hitachi H8/300, H8/500 and Super-H.
6053 * New targets supported
6055 H8/300 simulator h8300-hitachi-hms or h8300hms
6056 H8/500 simulator h8500-hitachi-hms or h8500hms
6057 SH simulator sh-hitachi-hms or sh
6058 Z8000 simulator z8k-zilog-none or z8ksim
6059 IDT MIPS board over serial line mips-idt-ecoff
6061 Cross-debugging to GO32 targets is supported. It requires a custom
6062 version of the i386-stub.c module which is integrated with the
6063 GO32 memory extender.
6065 * New remote protocols
6067 MIPS remote debugging protocol.
6069 * New source languages supported
6071 This version includes preliminary support for Chill, a Pascal like language
6072 used by telecommunications companies. Chill support is also being integrated
6073 into the GNU compiler, but we don't know when it will be publically available.
6076 *** Changes in GDB-4.8:
6078 * HP Precision Architecture supported
6080 GDB now supports HP PA-RISC machines running HPUX. A preliminary
6081 version of this support was available as a set of patches from the
6082 University of Utah. GDB does not support debugging of programs
6083 compiled with the HP compiler, because HP will not document their file
6084 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
6085 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
6087 Many problems in the preliminary version have been fixed.
6089 * Faster and better demangling
6091 We have improved template demangling and fixed numerous bugs in the GNU style
6092 demangler. It can now handle type modifiers such as `static' or `const'. Wide
6093 character types (wchar_t) are now supported. Demangling of each symbol is now
6094 only done once, and is cached when the symbol table for a file is read in.
6095 This results in a small increase in memory usage for C programs, a moderate
6096 increase in memory usage for C++ programs, and a fantastic speedup in
6099 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
6100 from the specifications in the Annotated Reference Manual, which AT&T's
6101 compiler does not actually implement.
6103 * G++ multiple inheritance compiler problem
6105 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
6106 inheritance lattices was reworked to properly discover ambiguities. We
6107 recently found an example which causes this new algorithm to fail in a
6108 very subtle way, producing bad debug information for those classes.
6109 The file 'gcc.patch' (in this directory) can be applied to gcc to
6110 circumvent the problem. A future GCC release will contain a complete
6113 The previous G++ debug info problem (mentioned below for the gdb-4.7
6114 release) is fixed in gcc version 2.3.2.
6116 * Improved configure script
6118 The `configure' script will now attempt to guess your system type if
6119 you don't supply a host system type. The old scheme of supplying a
6120 host system triplet is preferable over using this. All the magic is
6121 done in the new `config.guess' script. Examine it for details.
6123 We have also brought our configure script much more in line with the FSF's
6124 version. It now supports the --with-xxx options. In particular,
6125 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
6126 The resulting GDB will not be able to read arbitrary object file formats --
6127 only the format ``expected'' to be used on the configured target system.
6128 We hope to make this the default in a future release.
6130 * Documentation improvements
6132 There's new internal documentation on how to modify GDB, and how to
6133 produce clean changes to the code. We implore people to read it
6134 before submitting changes.
6136 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
6137 M4 macros. The new texinfo.tex is provided in this release. Pre-built
6138 `info' files are also provided. To build `info' files from scratch,
6139 you will need the latest `makeinfo' release, which will be available in
6140 a future texinfo-X.Y release.
6142 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
6143 We're not sure exactly which versions have this problem, but it has
6144 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
6145 or better. If that isn't possible, there is a patch in
6146 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
6147 around this problem.
6151 GDB now supports array constants that can be used in expressions typed in by
6152 the user. The syntax is `{element, element, ...}'. Ie: you can now type
6153 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
6156 The new directory `gdb/sparclite' contains a program that demonstrates
6157 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
6159 * New native hosts supported
6161 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
6162 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
6164 * New targets supported
6166 AMD 29k family via UDI a29k-amd-udi or udi29k
6168 * New file formats supported
6170 BFD now supports reading HP/PA-RISC executables (SOM file format?),
6171 HPUX core files, and SCO 3.2v2 core files.
6175 Attaching to processes now works again; thanks for the many bug reports.
6177 We have also stomped on a bunch of core dumps caused by
6178 printf_filtered("%s") problems.
6180 We eliminated a copyright problem on the rpc and ptrace header files
6181 for VxWorks, which was discovered at the last minute during the 4.7
6182 release. You should now be able to build a VxWorks GDB.
6184 You can now interrupt gdb while an attached process is running. This
6185 will cause the attached process to stop, and give control back to GDB.
6187 We fixed problems caused by using too many file descriptors
6188 for reading symbols from object files and libraries. This was
6189 especially a problem for programs that used many (~100) shared
6192 The `step' command now only enters a subroutine if there is line number
6193 information for the subroutine. Otherwise it acts like the `next'
6194 command. Previously, `step' would enter subroutines if there was
6195 any debugging information about the routine. This avoids problems
6196 when using `cc -g1' on MIPS machines.
6198 * Internal improvements
6200 GDB's internal interfaces have been improved to make it easier to support
6201 debugging of multiple languages in the future.
6203 GDB now uses a common structure for symbol information internally.
6204 Minimal symbols (derived from linkage symbols in object files), partial
6205 symbols (from a quick scan of debug information), and full symbols
6206 contain a common subset of information, making it easier to write
6207 shared code that handles any of them.
6209 * New command line options
6211 We now accept --silent as an alias for --quiet.
6215 The memory-mapped-malloc library is now licensed under the GNU Library
6216 General Public License.
6218 *** Changes in GDB-4.7:
6220 * Host/native/target split
6222 GDB has had some major internal surgery to untangle the support for
6223 hosts and remote targets. Now, when you configure GDB for a remote
6224 target, it will no longer load in all of the support for debugging
6225 local programs on the host. When fully completed and tested, this will
6226 ensure that arbitrary host/target combinations are possible.
6228 The primary conceptual shift is to separate the non-portable code in
6229 GDB into three categories. Host specific code is required any time GDB
6230 is compiled on that host, regardless of the target. Target specific
6231 code relates to the peculiarities of the target, but can be compiled on
6232 any host. Native specific code is everything else: it can only be
6233 built when the host and target are the same system. Child process
6234 handling and core file support are two common `native' examples.
6236 GDB's use of /proc for controlling Unix child processes is now cleaner.
6237 It has been split out into a single module under the `target_ops' vector,
6238 plus two native-dependent functions for each system that uses /proc.
6240 * New hosts supported
6242 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6243 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6244 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6246 * New targets supported
6248 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6249 68030 and CPU32 m68030-*-*, m68332-*-*
6251 * New native hosts supported
6253 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6254 (386bsd is not well tested yet)
6255 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6257 * New file formats supported
6259 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6260 supports reading of `a.out.adobe' object files, which are an a.out
6261 format extended with minimal information about multiple sections.
6265 `show copying' is the same as the old `info copying'.
6266 `show warranty' is the same as `info warrantee'.
6267 These were renamed for consistency. The old commands continue to work.
6269 `info handle' is a new alias for `info signals'.
6271 You can now define pre-command hooks, which attach arbitrary command
6272 scripts to any command. The commands in the hook will be executed
6273 prior to the user's command. You can also create a hook which will be
6274 executed whenever the program stops. See gdb.texinfo.
6278 We now deal with Cfront style name mangling, and can even extract type
6279 info from mangled symbols. GDB can automatically figure out which
6280 symbol mangling style your C++ compiler uses.
6282 Calling of methods and virtual functions has been improved as well.
6286 The crash that occured when debugging Sun Ansi-C compiled binaries is
6287 fixed. This was due to mishandling of the extra N_SO stabs output
6290 We also finally got Ultrix 4.2 running in house, and fixed core file
6291 support, with help from a dozen people on the net.
6293 John M. Farrell discovered that the reason that single-stepping was so
6294 slow on all of the Mips based platforms (primarily SGI and DEC) was
6295 that we were trying to demangle and lookup a symbol used for internal
6296 purposes on every instruction that was being stepped through. Changing
6297 the name of that symbol so that it couldn't be mistaken for a C++
6298 mangled symbol sped things up a great deal.
6300 Rich Pixley sped up symbol lookups in general by getting much smarter
6301 about when C++ symbol mangling is necessary. This should make symbol
6302 completion (TAB on the command line) much faster. It's not as fast as
6303 we'd like, but it's significantly faster than gdb-4.6.
6307 A new user controllable variable 'call_scratch_address' can
6308 specify the location of a scratch area to be used when GDB
6309 calls a function in the target. This is necessary because the
6310 usual method of putting the scratch area on the stack does not work
6311 in systems that have separate instruction and data spaces.
6313 We integrated changes to support the 29k UDI (Universal Debugger
6314 Interface), but discovered at the last minute that we didn't have all
6315 of the appropriate copyright paperwork. We are working with AMD to
6316 resolve this, and hope to have it available soon.
6320 We have sped up the remote serial line protocol, especially for targets
6321 with lots of registers. It now supports a new `expedited status' ('T')
6322 message which can be used in place of the existing 'S' status message.
6323 This allows the remote stub to send only the registers that GDB
6324 needs to make a quick decision about single-stepping or conditional
6325 breakpoints, eliminating the need to fetch the entire register set for
6326 each instruction being stepped through.
6328 The GDB remote serial protocol now implements a write-through cache for
6329 registers, only re-reading the registers if the target has run.
6331 There is also a new remote serial stub for SPARC processors. You can
6332 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6333 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6334 processor with a serial port.
6338 Configure.in files have become much easier to read and modify. A new
6339 `table driven' format makes it more obvious what configurations are
6340 supported, and what files each one uses.
6344 There is a new opcodes library which will eventually contain all of the
6345 disassembly routines and opcode tables. At present, it only contains
6346 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6347 disassembler (binutils/objdump) to share these routines.
6349 The libiberty library is now copylefted under the GNU Library General
6350 Public License. This allows more liberal use, and was done so libg++
6351 can use it. This makes no difference to GDB, since the Library License
6352 grants all the rights from the General Public License.
6356 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6357 reference to the stabs symbol info used by the debugger. It is (as far
6358 as we know) the only published document on this fascinating topic. We
6359 encourage you to read it, compare it to the stabs information on your
6360 system, and send improvements on the document in general (to
6361 bug-gdb@prep.ai.mit.edu).
6363 And, of course, many bugs have been fixed.
6366 *** Changes in GDB-4.6:
6368 * Better support for C++ function names
6370 GDB now accepts as input the "demangled form" of C++ overloaded function
6371 names and member function names, and can do command completion on such names
6372 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6373 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6374 Make use of command completion, it is your friend.
6376 GDB also now accepts a variety of C++ mangled symbol formats. They are
6377 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6378 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6379 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6380 for the list of formats.
6382 * G++ symbol mangling problem
6384 Recent versions of gcc have a bug in how they emit debugging information for
6385 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6386 directory) can be applied to gcc to fix the problem. Alternatively, if you
6387 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6388 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6389 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6392 * New 'maintenance' command
6394 All of the commands related to hacking GDB internals have been moved out of
6395 the main command set, and now live behind the 'maintenance' command. This
6396 can also be abbreviated as 'mt'. The following changes were made:
6398 dump-me -> maintenance dump-me
6399 info all-breakpoints -> maintenance info breakpoints
6400 printmsyms -> maintenance print msyms
6401 printobjfiles -> maintenance print objfiles
6402 printpsyms -> maintenance print psymbols
6403 printsyms -> maintenance print symbols
6405 The following commands are new:
6407 maintenance demangle Call internal GDB demangler routine to
6408 demangle a C++ link name and prints the result.
6409 maintenance print type Print a type chain for a given symbol
6411 * Change to .gdbinit file processing
6413 We now read the $HOME/.gdbinit file before processing the argv arguments
6414 (e.g. reading symbol files or core files). This allows global parameters to
6415 be set, which will apply during the symbol reading. The ./.gdbinit is still
6416 read after argv processing.
6418 * New hosts supported
6420 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6422 GNU/Linux support i386-unknown-linux or linux
6424 We are also including code to support the HP/PA running BSD and HPUX. This
6425 is almost guaranteed not to work, as we didn't have time to test or build it
6426 for this release. We are including it so that the more adventurous (or
6427 masochistic) of you can play with it. We also had major problems with the
6428 fact that the compiler that we got from HP doesn't support the -g option.
6431 * New targets supported
6433 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6435 * More smarts about finding #include files
6437 GDB now remembers the compilation directory for all include files, and for
6438 all files from which C is generated (like yacc and lex sources). This
6439 greatly improves GDB's ability to find yacc/lex sources, and include files,
6440 especially if you are debugging your program from a directory different from
6441 the one that contains your sources.
6443 We also fixed a bug which caused difficulty with listing and setting
6444 breakpoints in include files which contain C code. (In the past, you had to
6445 try twice in order to list an include file that you hadn't looked at before.)
6447 * Interesting infernals change
6449 GDB now deals with arbitrary numbers of sections, where the symbols for each
6450 section must be relocated relative to that section's landing place in the
6451 target's address space. This work was needed to support ELF with embedded
6452 stabs used by Solaris-2.0.
6454 * Bug fixes (of course!)
6456 There have been loads of fixes for the following things:
6457 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6458 i960, stabs, DOS(GO32), procfs, etc...
6460 See the ChangeLog for details.
6462 *** Changes in GDB-4.5:
6464 * New machines supported (host and target)
6466 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6468 SGI Irix-4.x mips-sgi-irix4 or iris4
6470 * New malloc package
6472 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6473 Mmalloc is capable of handling mutiple heaps of memory. It is also
6474 capable of saving a heap to a file, and then mapping it back in later.
6475 This can be used to greatly speedup the startup of GDB by using a
6476 pre-parsed symbol table which lives in a mmalloc managed heap. For
6477 more details, please read mmalloc/mmalloc.texi.
6481 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6482 'help info proc' for details.
6484 * MIPS ecoff symbol table format
6486 The code that reads MIPS symbol table format is now supported on all hosts.
6487 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6490 * File name changes for MS-DOS
6492 Many files in the config directories have been renamed to make it easier to
6493 support GDB on MS-DOSe systems (which have very restrictive file name
6494 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6495 environment) is close to working but has some remaining problems. Note
6496 that debugging of DOS programs is not supported, due to limitations
6497 in the ``operating system'', but it can be used to host cross-debugging.
6499 * Cross byte order fixes
6501 Many fixes have been made to support cross debugging of Sparc and MIPS
6502 targets from hosts whose byte order differs.
6504 * New -mapped and -readnow options
6506 If memory-mapped files are available on your system through the 'mmap'
6507 system call, you can use the -mapped option on the `file' or
6508 `symbol-file' commands to cause GDB to write the symbols from your
6509 program into a reusable file. If the program you are debugging is
6510 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6511 Future GDB debugging sessions will notice the presence of this file,
6512 and will quickly map in symbol information from it, rather than reading
6513 the symbol table from the executable program. Using the '-mapped'
6514 option in a GDB `file' or `symbol-file' command has the same effect as
6515 starting GDB with the '-mapped' command-line option.
6517 You can cause GDB to read the entire symbol table immediately by using
6518 the '-readnow' option with any of the commands that load symbol table
6519 information (or on the GDB command line). This makes the command
6520 slower, but makes future operations faster.
6522 The -mapped and -readnow options are typically combined in order to
6523 build a `fred.syms' file that contains complete symbol information.
6524 A simple GDB invocation to do nothing but build a `.syms' file for future
6527 gdb -batch -nx -mapped -readnow programname
6529 The `.syms' file is specific to the host machine on which GDB is run.
6530 It holds an exact image of GDB's internal symbol table. It cannot be
6531 shared across multiple host platforms.
6533 * longjmp() handling
6535 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6536 siglongjmp() without losing control. This feature has not yet been ported to
6537 all systems. It currently works on many 386 platforms, all MIPS-based
6538 platforms (SGI, DECstation, etc), and Sun3/4.
6542 Preliminary work has been put in to support the new Solaris OS from Sun. At
6543 this time, it can control and debug processes, but it is not capable of
6548 As always, many many bug fixes. The major areas were with g++, and mipsread.
6549 People using the MIPS-based platforms should experience fewer mysterious
6550 crashes and trashed symbol tables.
6552 *** Changes in GDB-4.4:
6554 * New machines supported (host and target)
6556 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6558 BSD Reno on Vax vax-dec-bsd
6559 Ultrix on Vax vax-dec-ultrix
6561 * New machines supported (target)
6563 AMD 29000 embedded, using EBMON a29k-none-none
6567 GDB continues to improve its handling of C++. `References' work better.
6568 The demangler has also been improved, and now deals with symbols mangled as
6569 per the Annotated C++ Reference Guide.
6571 GDB also now handles `stabs' symbol information embedded in MIPS
6572 `ecoff' symbol tables. Since the ecoff format was not easily
6573 extensible to handle new languages such as C++, this appeared to be a
6574 good way to put C++ debugging info into MIPS binaries. This option
6575 will be supported in the GNU C compiler, version 2, when it is
6578 * New features for SVR4
6580 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6581 shared libraries. Debugging dynamically linked programs should present
6582 only minor differences from debugging statically linked programs.
6584 The `info proc' command will print out information about any process
6585 on an SVR4 system (including the one you are debugging). At the moment,
6586 it prints the address mappings of the process.
6588 If you bring up GDB on another SVR4 system, please send mail to
6589 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6591 * Better dynamic linking support in SunOS
6593 Reading symbols from shared libraries which contain debugging symbols
6594 now works properly. However, there remain issues such as automatic
6595 skipping of `transfer vector' code during function calls, which
6596 make it harder to debug code in a shared library, than to debug the
6597 same code linked statically.
6601 GDB is now using the latest `getopt' routines from the FSF. This
6602 version accepts the -- prefix for options with long names. GDB will
6603 continue to accept the old forms (-option and +option) as well.
6604 Various single letter abbreviations for options have been explicity
6605 added to the option table so that they won't get overshadowed in the
6606 future by other options that begin with the same letter.
6610 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6611 Many assorted bugs have been handled. Many more remain to be handled.
6612 See the various ChangeLog files (primarily in gdb and bfd) for details.
6615 *** Changes in GDB-4.3:
6617 * New machines supported (host and target)
6619 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6620 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6621 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6623 * Almost SCO Unix support
6625 We had hoped to support:
6626 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6627 (except for core file support), but we discovered very late in the release
6628 that it has problems with process groups that render gdb unusable. Sorry
6629 about that. I encourage people to fix it and post the fixes.
6631 * Preliminary ELF and DWARF support
6633 GDB can read ELF object files on System V Release 4, and can handle
6634 debugging records for C, in DWARF format, in ELF files. This support
6635 is preliminary. If you bring up GDB on another SVR4 system, please
6636 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6641 GDB now uses the latest `readline' library. One user-visible change
6642 is that two tabs will list possible command completions, which previously
6643 required typing M-? (meta-question mark, or ESC ?).
6647 The `stepi' bug that many of you noticed has been squashed.
6648 Many bugs in C++ have been handled. Many more remain to be handled.
6649 See the various ChangeLog files (primarily in gdb and bfd) for details.
6651 * State of the MIPS world (in case you wondered):
6653 GDB can understand the symbol tables emitted by the compilers
6654 supplied by most vendors of MIPS-based machines, including DEC. These
6655 symbol tables are in a format that essentially nobody else uses.
6657 Some versions of gcc come with an assembler post-processor called
6658 mips-tfile. This program is required if you want to do source-level
6659 debugging of gcc-compiled programs. I believe FSF does not ship
6660 mips-tfile with gcc version 1, but it will eventually come with gcc
6663 Debugging of g++ output remains a problem. g++ version 1.xx does not
6664 really support it at all. (If you're lucky, you should be able to get
6665 line numbers and stack traces to work, but no parameters or local
6666 variables.) With some work it should be possible to improve the
6669 When gcc version 2 is released, you will have somewhat better luck.
6670 However, even then you will get confusing results for inheritance and
6673 We will eventually provide full debugging of g++ output on
6674 DECstations. This will probably involve some kind of stabs-in-ecoff
6675 encapulation, but the details have not been worked out yet.
6678 *** Changes in GDB-4.2:
6680 * Improved configuration
6682 Only one copy of `configure' exists now, and it is not self-modifying.
6683 Porting BFD is simpler.
6687 The `step' and `next' commands now only stop at the first instruction
6688 of a source line. This prevents the multiple stops that used to occur
6689 in switch statements, for-loops, etc. `Step' continues to stop if a
6690 function that has debugging information is called within the line.
6694 Lots of small bugs fixed. More remain.
6696 * New host supported (not target)
6698 Intel 386 PC clone running Mach i386-none-mach
6701 *** Changes in GDB-4.1:
6703 * Multiple source language support
6705 GDB now has internal scaffolding to handle several source languages.
6706 It determines the type of each source file from its filename extension,
6707 and will switch expression parsing and number formatting to match the
6708 language of the function in the currently selected stack frame.
6709 You can also specifically set the language to be used, with
6710 `set language c' or `set language modula-2'.
6714 GDB now has preliminary support for the GNU Modula-2 compiler,
6715 currently under development at the State University of New York at
6716 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6717 continue through the fall of 1991 and into 1992.
6719 Other Modula-2 compilers are currently not supported, and attempting to
6720 debug programs compiled with them will likely result in an error as the
6721 symbol table is read. Feel free to work on it, though!
6723 There are hooks in GDB for strict type checking and range checking,
6724 in the `Modula-2 philosophy', but they do not currently work.
6728 GDB can now write to executable and core files (e.g. patch
6729 a variable's value). You must turn this switch on, specify
6730 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6731 by assigning a new value to a variable. Modifications take
6734 * Automatic SunOS shared library reading
6736 When you run your program, GDB automatically determines where its
6737 shared libraries (if any) have been loaded, and reads their symbols.
6738 The `share' command is no longer needed. This also works when
6739 examining core files.
6743 You can specify the number of lines that the `list' command shows.
6746 * New machines supported (host and target)
6748 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6749 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6750 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6752 * New hosts supported (not targets)
6754 IBM RT/PC: romp-ibm-aix or rtpc
6756 * New targets supported (not hosts)
6758 AMD 29000 embedded with COFF a29k-none-coff
6759 AMD 29000 embedded with a.out a29k-none-aout
6760 Ultracomputer remote kernel debug a29k-nyu-kern
6762 * New remote interfaces
6768 *** Changes in GDB-4.0:
6772 Wide output is wrapped at good places to make the output more readable.
6774 Gdb now supports cross-debugging from a host machine of one type to a
6775 target machine of another type. Communication with the target system
6776 is over serial lines. The ``target'' command handles connecting to the
6777 remote system; the ``load'' command will download a program into the
6778 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6779 also supports debugging of realtime processes running under VxWorks,
6780 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6781 stub on the target system.
6783 New CPUs supported include the AMD 29000 and Intel 960.
6785 GDB now reads object files and symbol tables via a ``binary file''
6786 library, which allows a single copy of GDB to debug programs of multiple
6787 object file types such as a.out and coff.
6789 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6790 refcard.dvi and refcard.ps are available to format it).
6793 * Control-Variable user interface simplified
6795 All variables that control the operation of the debugger can be set
6796 by the ``set'' command, and displayed by the ``show'' command.
6798 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6799 ``Show prompt'' produces the response:
6800 Gdb's prompt is new-gdb=>.
6802 What follows are the NEW set commands. The command ``help set'' will
6803 print a complete list of old and new set commands. ``help set FOO''
6804 will give a longer description of the variable FOO. ``show'' will show
6805 all of the variable descriptions and their current settings.
6807 confirm on/off: Enables warning questions for operations that are
6808 hard to recover from, e.g. rerunning the program while
6809 it is already running. Default is ON.
6811 editing on/off: Enables EMACS style command line editing
6812 of input. Previous lines can be recalled with
6813 control-P, the current line can be edited with control-B,
6814 you can search for commands with control-R, etc.
6817 history filename NAME: NAME is where the gdb command history
6818 will be stored. The default is .gdb_history,
6819 or the value of the environment variable
6822 history size N: The size, in commands, of the command history. The
6823 default is 256, or the value of the environment variable
6826 history save on/off: If this value is set to ON, the history file will
6827 be saved after exiting gdb. If set to OFF, the
6828 file will not be saved. The default is OFF.
6830 history expansion on/off: If this value is set to ON, then csh-like
6831 history expansion will be performed on
6832 command line input. The default is OFF.
6834 radix N: Sets the default radix for input and output. It can be set
6835 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6836 in the current radix, so "set radix 10" is always a no-op.
6838 height N: This integer value is the number of lines on a page. Default
6839 is 24, the current `stty rows'' setting, or the ``li#''
6840 setting from the termcap entry matching the environment
6843 width N: This integer value is the number of characters on a line.
6844 Default is 80, the current `stty cols'' setting, or the ``co#''
6845 setting from the termcap entry matching the environment
6848 Note: ``set screensize'' is obsolete. Use ``set height'' and
6849 ``set width'' instead.
6851 print address on/off: Print memory addresses in various command displays,
6852 such as stack traces and structure values. Gdb looks
6853 more ``symbolic'' if you turn this off; it looks more
6854 ``machine level'' with it on. Default is ON.
6856 print array on/off: Prettyprint arrays. New convenient format! Default
6859 print demangle on/off: Print C++ symbols in "source" form if on,
6862 print asm-demangle on/off: Same, for assembler level printouts
6865 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6868 * Support for Epoch Environment.
6870 The epoch environment is a version of Emacs v18 with windowing. One
6871 new command, ``inspect'', is identical to ``print'', except that if you
6872 are running in the epoch environment, the value is printed in its own
6876 * Support for Shared Libraries
6878 GDB can now debug programs and core files that use SunOS shared libraries.
6879 Symbols from a shared library cannot be referenced
6880 before the shared library has been linked with the program (this
6881 happens after you type ``run'' and before the function main() is entered).
6882 At any time after this linking (including when examining core files
6883 from dynamically linked programs), gdb reads the symbols from each
6884 shared library when you type the ``sharedlibrary'' command.
6885 It can be abbreviated ``share''.
6887 sharedlibrary REGEXP: Load shared object library symbols for files
6888 matching a unix regular expression. No argument
6889 indicates to load symbols for all shared libraries.
6891 info sharedlibrary: Status of loaded shared libraries.
6896 A watchpoint stops execution of a program whenever the value of an
6897 expression changes. Checking for this slows down execution
6898 tremendously whenever you are in the scope of the expression, but is
6899 quite useful for catching tough ``bit-spreader'' or pointer misuse
6900 problems. Some machines such as the 386 have hardware for doing this
6901 more quickly, and future versions of gdb will use this hardware.
6903 watch EXP: Set a watchpoint (breakpoint) for an expression.
6905 info watchpoints: Information about your watchpoints.
6907 delete N: Deletes watchpoint number N (same as breakpoints).
6908 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6909 enable N: Re-enables watchpoint number N (same as breakpoints).
6912 * C++ multiple inheritance
6914 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6917 * C++ exception handling
6919 Gdb now supports limited C++ exception handling. Besides the existing
6920 ability to breakpoint on an exception handler, gdb can breakpoint on
6921 the raising of an exception (before the stack is peeled back to the
6924 catch FOO: If there is a FOO exception handler in the dynamic scope,
6925 set a breakpoint to catch exceptions which may be raised there.
6926 Multiple exceptions (``catch foo bar baz'') may be caught.
6928 info catch: Lists all exceptions which may be caught in the
6929 current stack frame.
6932 * Minor command changes
6934 The command ``call func (arg, arg, ...)'' now acts like the print
6935 command, except it does not print or save a value if the function's result
6936 is void. This is similar to dbx usage.
6938 The ``up'' and ``down'' commands now always print the frame they end up
6939 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6940 frames without printing.
6942 * New directory command
6944 'dir' now adds directories to the FRONT of the source search path.
6945 The path starts off empty. Source files that contain debug information
6946 about the directory in which they were compiled can be found even
6947 with an empty path; Sun CC and GCC include this information. If GDB can't
6948 find your source file in the current directory, type "dir .".
6950 * Configuring GDB for compilation
6952 For normal use, type ``./configure host''. See README or gdb.texinfo
6955 GDB now handles cross debugging. If you are remotely debugging between
6956 two different machines, type ``./configure host -target=targ''.
6957 Host is the machine where GDB will run; targ is the machine
6958 where the program that you are debugging will run.