1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 8.0
6 * GDB now supports access to the guarded-storage-control registers and the
7 software-based guarded-storage broadcast control registers on IBM z14.
9 * On Unix systems, GDB now supports transmitting environment variables
10 that are to be set or unset to GDBserver. These variables will
11 affect the environment to be passed to the remote inferior.
13 To inform GDB of environment variables that are to be transmitted to
14 GDBserver, use the "set environment" command. Only user set
15 environment variables are sent to GDBserver.
17 To inform GDB of environment variables that are to be unset before
18 the remote inferior is started by the GDBserver, use the "unset
23 ** New events gdb.new_inferior, gdb.inferior_deleted, and
24 gdb.new_thread are emitted. See the manual for further
27 * New features in the GDB remote stub, GDBserver
29 ** New "--selftest" command line option runs some GDBserver self
30 tests. These self tests are disabled in releases.
32 ** On Unix systems, GDBserver now does globbing expansion and variable
33 substitution in inferior command line arguments.
35 This is done by starting inferiors using a shell, like GDB does.
36 See "set startup-with-shell" in the user manual for how to disable
37 this from GDB when using "target extended-remote". When using
38 "target remote", you can disable the startup with shell by using the
39 new "--no-startup-with-shell" GDBserver command line option.
41 ** On Unix systems, GDBserver now supports receiving environment
42 variables that are to be set or unset from GDB. These variables
43 will affect the environment to be passed to the inferior.
47 QEnvironmentHexEncoded
48 Inform GDBserver of an environment variable that is to be passed to
49 the inferior when starting it.
52 Inform GDBserver of an environment variable that is to be unset
53 before starting the remote inferior.
56 Inform GDBserver that the environment should be reset (i.e.,
57 user-set environment variables should be unset).
60 Indicates whether the inferior must be started with a shell or not.
62 * The "maintenance print c-tdesc" command now takes an optional
63 argument which is the file name of XML target description.
65 * The "maintenance selftest" command now takes an optional argument to
66 filter the tests to be run.
71 Set and show the current working directory for the inferior.
74 Set and show compilation command used for compiling and injecting code
75 with the 'compile' commands.
77 set debug separate-debug-file
78 show debug separate-debug-file
79 Control the display of debug output about separate debug file search.
82 List the registered selftests.
85 Start the debugged program stopping at the first instruction.
87 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
90 * Safer/improved support for debugging with no debug info
92 GDB no longer assumes functions with no debug information return
95 This means that GDB now refuses to call such functions unless you
96 tell it the function's type, by either casting the call to the
97 declared return type, or by casting the function to a function
98 pointer of the right type, and calling that:
100 (gdb) p getenv ("PATH")
101 'getenv' has unknown return type; cast the call to its declared return type
102 (gdb) p (char *) getenv ("PATH")
103 $1 = 0x7fffffffe "/usr/local/bin:/"...
104 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
105 $2 = 0x7fffffffe "/usr/local/bin:/"...
107 Similarly, GDB no longer assumes that global variables with no debug
108 info have type 'int', and refuses to print the variable's value
109 unless you tell it the variable's type:
112 'var' has unknown type; cast it to its declared type
116 * New native configurations
118 FreeBSD/aarch64 aarch64*-*-freebsd*
122 FreeBSD/aarch64 aarch64*-*-freebsd*
124 * Removed targets and native configurations
126 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
128 *** Changes in GDB 8.0
130 * GDB now supports access to the PKU register on GNU/Linux. The register is
131 added by the Memory Protection Keys for Userspace feature which will be
132 available in future Intel CPUs.
134 * GDB now supports C++11 rvalue references.
138 ** New functions to start, stop and access a running btrace recording.
139 ** Rvalue references are now supported in gdb.Type.
141 * GDB now supports recording and replaying rdrand and rdseed Intel 64
144 * Building GDB and GDBserver now requires a C++11 compiler.
146 For example, GCC 4.8 or later.
148 It is no longer possible to build GDB or GDBserver with a C
149 compiler. The --disable-build-with-cxx configure option has been
152 * Building GDB and GDBserver now requires GNU make >= 3.81.
154 It is no longer supported to build GDB or GDBserver with another
155 implementation of the make program or an earlier version of GNU make.
157 * Native debugging on MS-Windows supports command-line redirection
159 Command-line arguments used for starting programs on MS-Windows can
160 now include redirection symbols supported by native Windows shells,
161 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
162 as "run", "start", and "set args", as well as the corresponding MI
165 * Support for thread names on MS-Windows.
167 GDB now catches and handles the special exception that programs
168 running on MS-Windows use to assign names to threads in the
171 * Support for Java programs compiled with gcj has been removed.
173 * User commands now accept an unlimited number of arguments.
174 Previously, only up to 10 was accepted.
176 * The "eval" command now expands user-defined command arguments.
178 This makes it easier to process a variable number of arguments:
183 eval "print $arg%d", $i
188 * Target descriptions can now describe registers for sparc32 and sparc64.
190 * GDB now supports DWARF version 5 (debug information format).
191 Its .debug_names index is not yet supported.
193 * New native configurations
195 FreeBSD/mips mips*-*-freebsd
199 Synopsys ARC arc*-*-elf32
200 FreeBSD/mips mips*-*-freebsd
202 * Removed targets and native configurations
204 Alpha running FreeBSD alpha*-*-freebsd*
205 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
210 Erases all the flash memory regions reported by the target.
212 maint print arc arc-instruction address
213 Print internal disassembler information about instruction at a given address.
217 set disassembler-options
218 show disassembler-options
219 Controls the passing of target specific information to the disassembler.
220 If it is necessary to specify more than one disassembler option then
221 multiple options can be placed together into a comma separated list.
222 The default value is the empty string. Currently, the only supported
223 targets are ARM, PowerPC and S/390.
228 Erases all the flash memory regions reported by the target. This is
229 equivalent to the CLI command flash-erase.
231 -file-list-shared-libraries
232 List the shared libraries in the program. This is
233 equivalent to the CLI command "info shared".
235 *** Changes in GDB 7.12
237 * GDB and GDBserver now build with a C++ compiler by default.
239 The --enable-build-with-cxx configure option is now enabled by
240 default. One must now explicitly configure with
241 --disable-build-with-cxx in order to build with a C compiler. This
242 option will be removed in a future release.
244 * GDBserver now supports recording btrace without maintaining an active
247 * GDB now supports a negative repeat count in the 'x' command to examine
248 memory backward from the given address. For example:
251 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
252 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
253 (gdb) x/-5i 0x0000000000400580
254 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
255 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
256 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
257 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
258 0x40057b <main(int, char**)+25>:
259 callq 0x400536 <Func1(int, char const*)>
261 * Fortran: Support structures with fields of dynamic types and
262 arrays of dynamic types.
264 * The symbol dumping maintenance commands have new syntax.
265 maint print symbols [-pc address] [--] [filename]
266 maint print symbols [-objfile objfile] [-source source] [--] [filename]
267 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
268 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
269 maint print msymbols [-objfile objfile] [--] [filename]
271 * GDB now supports multibit bitfields and enums in target register
274 * New Python-based convenience function $_as_string(val), which returns
275 the textual representation of a value. This function is especially
276 useful to obtain the text label of an enum value.
278 * Intel MPX bound violation handling.
280 Segmentation faults caused by a Intel MPX boundary violation
281 now display the kind of violation (upper or lower), the memory
282 address accessed and the memory bounds, along with the usual
283 signal received and code location.
287 Program received signal SIGSEGV, Segmentation fault
288 Upper bound violation while accessing address 0x7fffffffc3b3
289 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
290 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
292 * Rust language support.
293 GDB now supports debugging programs written in the Rust programming
294 language. See https://www.rust-lang.org/ for more information about
297 * Support for running interpreters on specified input/output devices
299 GDB now supports a new mechanism that allows frontends to provide
300 fully featured GDB console views, as a better alternative to
301 building such views on top of the "-interpreter-exec console"
302 command. See the new "new-ui" command below. With that command,
303 frontends can now start GDB in the traditional command-line mode
304 running in an embedded terminal emulator widget, and create a
305 separate MI interpreter running on a specified i/o device. In this
306 way, GDB handles line editing, history, tab completion, etc. in the
307 console all by itself, and the GUI uses the separate MI interpreter
308 for its own control and synchronization, invisible to the command
311 * The "catch syscall" command catches groups of related syscalls.
313 The "catch syscall" command now supports catching a group of related
314 syscalls using the 'group:' or 'g:' prefix.
319 skip -gfile file-glob-pattern
320 skip -function function
321 skip -rfunction regular-expression
322 A generalized form of the skip command, with new support for
323 glob-style file names and regular expressions for function names.
324 Additionally, a file spec and a function spec may now be combined.
326 maint info line-table REGEXP
327 Display the contents of GDB's internal line table data struture.
330 Run any GDB unit tests that were compiled in.
333 Start a new user interface instance running INTERP as interpreter,
334 using the TTY file for input/output.
338 ** gdb.Breakpoint objects have a new attribute "pending", which
339 indicates whether the breakpoint is pending.
340 ** Three new breakpoint-related events have been added:
341 gdb.breakpoint_created, gdb.breakpoint_modified, and
342 gdb.breakpoint_deleted.
345 Signal ("set") the given MS-Windows event object. This is used in
346 conjunction with the Windows JIT debugging (AeDebug) support, where
347 the OS suspends a crashing process until a debugger can attach to
348 it. Resuming the crashing process, in order to debug it, is done by
351 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
352 was added in GDBserver, including JIT compiling fast tracepoint's
353 conditional expression bytecode into native code.
355 * Support for various remote target protocols and ROM monitors has
358 target m32rsdi Remote M32R debugging over SDI
359 target mips MIPS remote debugging protocol
360 target pmon PMON ROM monitor
361 target ddb NEC's DDB variant of PMON for Vr4300
362 target rockhopper NEC RockHopper variant of PMON
363 target lsi LSI variant of PMO
365 * Support for tracepoints and fast tracepoints on powerpc-linux,
366 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
367 including JIT compiling fast tracepoint's conditional expression
368 bytecode into native code.
370 * MI async record =record-started now includes the method and format used for
371 recording. For example:
373 =record-started,thread-group="i1",method="btrace",format="bts"
375 * MI async record =thread-selected now includes the frame field. For example:
377 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
381 Andes NDS32 nds32*-*-elf
383 *** Changes in GDB 7.11
385 * GDB now supports debugging kernel-based threads on FreeBSD.
387 * Per-inferior thread numbers
389 Thread numbers are now per inferior instead of global. If you're
390 debugging multiple inferiors, GDB displays thread IDs using a
391 qualified INF_NUM.THR_NUM form. For example:
395 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
396 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
397 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
398 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
400 As consequence, thread numbers as visible in the $_thread
401 convenience variable and in Python's InferiorThread.num attribute
402 are no longer unique between inferiors.
404 GDB now maintains a second thread ID per thread, referred to as the
405 global thread ID, which is the new equivalent of thread numbers in
406 previous releases. See also $_gthread below.
408 For backwards compatibility, MI's thread IDs always refer to global
411 * Commands that accept thread IDs now accept the qualified
412 INF_NUM.THR_NUM form as well. For example:
415 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
418 * In commands that accept a list of thread IDs, you can now refer to
419 all threads of an inferior using a star wildcard. GDB accepts
420 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
421 refer to all threads of the current inferior. For example, "info
424 * You can use "info threads -gid" to display the global thread ID of
427 * The new convenience variable $_gthread holds the global number of
430 * The new convenience variable $_inferior holds the number of the
433 * GDB now displays the ID and name of the thread that hit a breakpoint
434 or received a signal, if your program is multi-threaded. For
437 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
438 Thread 1 "main" received signal SIGINT, Interrupt.
440 * Record btrace now supports non-stop mode.
442 * Support for tracepoints on aarch64-linux was added in GDBserver.
444 * The 'record instruction-history' command now indicates speculative execution
445 when using the Intel Processor Trace recording format.
447 * GDB now allows users to specify explicit locations, bypassing
448 the linespec parser. This feature is also available to GDB/MI
451 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
452 GDB now is able to debug both AArch64 applications and ARM applications
455 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
456 including JIT compiling fast tracepoint's conditional expression bytecode
459 * GDB now supports displaced stepping on AArch64 GNU/Linux.
461 * "info threads", "info inferiors", "info display", "info checkpoints"
462 and "maint info program-spaces" now list the corresponding items in
463 ascending ID order, for consistency with all other "info" commands.
465 * In Ada, the overloads selection menu has been enhanced to display the
466 parameter types and the return types for the matching overloaded subprograms.
470 maint set target-non-stop (on|off|auto)
471 maint show target-non-stop
472 Control whether GDB targets always operate in non-stop mode even if
473 "set non-stop" is "off". The default is "auto", meaning non-stop
474 mode is enabled if supported by the target.
476 maint set bfd-sharing
477 maint show bfd-sharing
478 Control the reuse of bfd objects.
482 Control display of debugging info regarding bfd caching.
486 Control display of debugging info regarding FreeBSD threads.
488 set remote multiprocess-extensions-packet
489 show remote multiprocess-extensions-packet
490 Set/show the use of the remote protocol multiprocess extensions.
492 set remote thread-events
493 show remote thread-events
494 Set/show the use of thread create/exit events.
496 set ada print-signatures on|off
497 show ada print-signatures"
498 Control whether parameter types and return types are displayed in overloads
499 selection menus. It is activaled (@code{on}) by default.
503 Controls the maximum size of memory, in bytes, that GDB will
504 allocate for value contents. Prevents incorrect programs from
505 causing GDB to allocate overly large buffers. Default is 64k.
507 * The "disassemble" command accepts a new modifier: /s.
508 It prints mixed source+disassembly like /m with two differences:
509 - disassembled instructions are now printed in program order, and
510 - and source for all relevant files is now printed.
511 The "/m" option is now considered deprecated: its "source-centric"
512 output hasn't proved useful in practice.
514 * The "record instruction-history" command accepts a new modifier: /s.
515 It behaves exactly like /m and prints mixed source+disassembly.
517 * The "set scheduler-locking" command supports a new mode "replay".
518 It behaves like "off" in record mode and like "on" in replay mode.
520 * Support for various ROM monitors has been removed:
522 target dbug dBUG ROM monitor for Motorola ColdFire
523 target picobug Motorola picobug monitor
524 target dink32 DINK32 ROM monitor for PowerPC
525 target m32r Renesas M32R/D ROM monitor
526 target mon2000 mon2000 ROM monitor
527 target ppcbug PPCBUG ROM monitor for PowerPC
529 * Support for reading/writing memory and extracting values on architectures
530 whose memory is addressable in units of any integral multiple of 8 bits.
535 Indicates that an exec system call was executed.
537 exec-events feature in qSupported
538 The qSupported packet allows GDB to request support for exec
539 events using the new 'gdbfeature' exec-event, and the qSupported
540 response can contain the corresponding 'stubfeature'. Set and
541 show commands can be used to display whether these features are enabled.
544 Equivalent to interrupting with the ^C character, but works in
547 thread created stop reason (T05 create:...)
548 Indicates that the thread was just created and is stopped at entry.
550 thread exit stop reply (w exitcode;tid)
551 Indicates that the thread has terminated.
554 Enables/disables thread create and exit event reporting. For
555 example, this is used in non-stop mode when GDB stops a set of
556 threads and synchronously waits for the their corresponding stop
557 replies. Without exit events, if one of the threads exits, GDB
558 would hang forever not knowing that it should no longer expect a
559 stop for that same thread.
562 Indicates that there are no resumed threads left in the target (all
563 threads are stopped). The remote stub reports support for this stop
564 reply to GDB's qSupported query.
567 Enables/disables catching syscalls from the inferior process.
568 The remote stub reports support for this packet to GDB's qSupported query.
570 syscall_entry stop reason
571 Indicates that a syscall was just called.
573 syscall_return stop reason
574 Indicates that a syscall just returned.
576 * Extended-remote exec events
578 ** GDB now has support for exec events on extended-remote Linux targets.
579 For such targets with Linux kernels 2.5.46 and later, this enables
580 follow-exec-mode and exec catchpoints.
582 set remote exec-event-feature-packet
583 show remote exec-event-feature-packet
584 Set/show the use of the remote exec event feature.
586 * Thread names in remote protocol
588 The reply to qXfer:threads:read may now include a name attribute for each
591 * Target remote mode fork and exec events
593 ** GDB now has support for fork and exec events on target remote mode
594 Linux targets. For such targets with Linux kernels 2.5.46 and later,
595 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
596 fork and exec catchpoints.
598 * Remote syscall events
600 ** GDB now has support for catch syscall on remote Linux targets,
601 currently enabled on x86/x86_64 architectures.
603 set remote catch-syscall-packet
604 show remote catch-syscall-packet
605 Set/show the use of the remote catch syscall feature.
609 ** The -var-set-format command now accepts the zero-hexadecimal
610 format. It outputs data in hexadecimal format with zero-padding on the
615 ** gdb.InferiorThread objects have a new attribute "global_num",
616 which refers to the thread's global thread ID. The existing
617 "num" attribute now refers to the thread's per-inferior number.
618 See "Per-inferior thread numbers" above.
619 ** gdb.InferiorThread objects have a new attribute "inferior", which
620 is the Inferior object the thread belongs to.
622 *** Changes in GDB 7.10
624 * Support for process record-replay and reverse debugging on aarch64*-linux*
625 targets has been added. GDB now supports recording of A64 instruction set
626 including advance SIMD instructions.
628 * Support for Sun's version of the "stabs" debug file format has been removed.
630 * GDB now honors the content of the file /proc/PID/coredump_filter
631 (PID is the process ID) on GNU/Linux systems. This file can be used
632 to specify the types of memory mappings that will be included in a
633 corefile. For more information, please refer to the manual page of
634 "core(5)". GDB also has a new command: "set use-coredump-filter
635 on|off". It allows to set whether GDB will read the content of the
636 /proc/PID/coredump_filter file when generating a corefile.
638 * The "info os" command on GNU/Linux can now display information on
640 "info os cpus" Listing of all cpus/cores on the system
642 * GDB has two new commands: "set serial parity odd|even|none" and
643 "show serial parity". These allows to set or show parity for the
646 * The "info source" command now displays the producer string if it was
647 present in the debug info. This typically includes the compiler version
648 and may include things like its command line arguments.
650 * The "info dll", an alias of the "info sharedlibrary" command,
651 is now available on all platforms.
653 * Directory names supplied to the "set sysroot" commands may be
654 prefixed with "target:" to tell GDB to access shared libraries from
655 the target system, be it local or remote. This replaces the prefix
656 "remote:". The default sysroot has been changed from "" to
657 "target:". "remote:" is automatically converted to "target:" for
658 backward compatibility.
660 * The system root specified by "set sysroot" will be prepended to the
661 filename of the main executable (if reported to GDB as absolute by
662 the operating system) when starting processes remotely, and when
663 attaching to already-running local or remote processes.
665 * GDB now supports automatic location and retrieval of executable
666 files from remote targets. Remote debugging can now be initiated
667 using only a "target remote" or "target extended-remote" command
668 (no "set sysroot" or "file" commands are required). See "New remote
671 * The "dump" command now supports verilog hex format.
673 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
675 * On GNU/Linux, GDB and gdbserver are now able to access executable
676 and shared library files without a "set sysroot" command when
677 attaching to processes running in different mount namespaces from
678 the debugger. This makes it possible to attach to processes in
679 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
680 See "New remote packets" below.
682 * The "tui reg" command now provides completion for all of the
683 available register groups, including target specific groups.
685 * The HISTSIZE environment variable is no longer read when determining
686 the size of GDB's command history. GDB now instead reads the dedicated
687 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
688 disables truncation of command history. Non-numeric values of GDBHISTSIZE
693 ** Memory ports can now be unbuffered.
697 ** gdb.Objfile objects have a new attribute "username",
698 which is the name of the objfile as specified by the user,
699 without, for example, resolving symlinks.
700 ** You can now write frame unwinders in Python.
701 ** gdb.Type objects have a new method "optimized_out",
702 returning optimized out gdb.Value instance of this type.
703 ** gdb.Value objects have new methods "reference_value" and
704 "const_value" which return a reference to the value and a
705 "const" version of the value respectively.
709 maint print symbol-cache
710 Print the contents of the symbol cache.
712 maint print symbol-cache-statistics
713 Print statistics of symbol cache usage.
715 maint flush-symbol-cache
716 Flush the contents of the symbol cache.
720 Start branch trace recording using Branch Trace Store (BTS) format.
723 Evaluate expression by using the compiler and print result.
727 Explicit commands for enabling and disabling tui mode.
730 set mpx bound on i386 and amd64
731 Support for bound table investigation on Intel MPX enabled applications.
735 Start branch trace recording using Intel Processor Trace format.
738 Print information about branch tracing internals.
740 maint btrace packet-history
741 Print the raw branch tracing data.
743 maint btrace clear-packet-history
744 Discard the stored raw branch tracing data.
747 Discard all branch tracing data. It will be fetched and processed
748 anew by the next "record" command.
753 Renamed from "set debug dwarf2-die".
755 Renamed from "show debug dwarf2-die".
758 Renamed from "set debug dwarf2-read".
759 show debug dwarf-read
760 Renamed from "show debug dwarf2-read".
762 maint set dwarf always-disassemble
763 Renamed from "maint set dwarf2 always-disassemble".
764 maint show dwarf always-disassemble
765 Renamed from "maint show dwarf2 always-disassemble".
767 maint set dwarf max-cache-age
768 Renamed from "maint set dwarf2 max-cache-age".
769 maint show dwarf max-cache-age
770 Renamed from "maint show dwarf2 max-cache-age".
773 show debug dwarf-line
774 Control display of debugging info regarding DWARF line processing.
778 Set the maximum number of candidates to be considered during
779 completion. The default value is 200. This limit allows GDB
780 to avoid generating large completion lists, the computation of
781 which can cause the debugger to become temporarily unresponsive.
783 set history remove-duplicates
784 show history remove-duplicates
785 Control the removal of duplicate history entries.
787 maint set symbol-cache-size
788 maint show symbol-cache-size
789 Control the size of the symbol cache.
791 set|show record btrace bts buffer-size
792 Set and show the size of the ring buffer used for branch tracing in
794 The obtained size may differ from the requested size. Use "info
795 record" to see the obtained buffer size.
797 set debug linux-namespaces
798 show debug linux-namespaces
799 Control display of debugging info regarding Linux namespaces.
801 set|show record btrace pt buffer-size
802 Set and show the size of the ring buffer used for branch tracing in
803 Intel Processor Trace format.
804 The obtained size may differ from the requested size. Use "info
805 record" to see the obtained buffer size.
807 maint set|show btrace pt skip-pad
808 Set and show whether PAD packets are skipped when computing the
811 * The command 'thread apply all' can now support new option '-ascending'
812 to call its specified command for all threads in ascending order.
814 * Python/Guile scripting
816 ** GDB now supports auto-loading of Python/Guile scripts contained in the
817 special section named `.debug_gdb_scripts'.
821 qXfer:btrace-conf:read
822 Return the branch trace configuration for the current thread.
824 Qbtrace-conf:bts:size
825 Set the requested ring buffer size for branch tracing in BTS format.
828 Enable Intel Procesor Trace-based branch tracing for the current
829 process. The remote stub reports support for this packet to GDB's
833 Set the requested ring buffer size for branch tracing in Intel Processor
837 Indicates a memory breakpoint instruction was executed, irrespective
838 of whether it was GDB that planted the breakpoint or the breakpoint
839 is hardcoded in the program. This is required for correct non-stop
843 Indicates the target stopped for a hardware breakpoint. This is
844 required for correct non-stop mode operation.
847 Return information about files on the remote system.
850 Return the full absolute name of the file that was executed to
851 create a process running on the remote system.
854 Select the filesystem on which vFile: operations with filename
855 arguments will operate. This is required for GDB to be able to
856 access files on remote targets where the remote stub does not
857 share a common filesystem with the inferior(s).
860 Indicates that a fork system call was executed.
863 Indicates that a vfork system call was executed.
865 vforkdone stop reason
866 Indicates that a vfork child of the specified process has executed
867 an exec or exit, allowing the vfork parent to resume execution.
869 fork-events and vfork-events features in qSupported
870 The qSupported packet allows GDB to request support for fork and
871 vfork events using new 'gdbfeatures' fork-events and vfork-events,
872 and the qSupported response can contain the corresponding
873 'stubfeatures'. Set and show commands can be used to display
874 whether these features are enabled.
876 * Extended-remote fork events
878 ** GDB now has support for fork events on extended-remote Linux
879 targets. For targets with Linux kernels 2.5.60 and later, this
880 enables follow-fork-mode and detach-on-fork for both fork and
881 vfork, as well as fork and vfork catchpoints.
883 * The info record command now shows the recording format and the
884 branch tracing configuration for the current thread when using
885 the btrace record target.
886 For the BTS format, it shows the ring buffer size.
888 * GDB now has support for DTrace USDT (Userland Static Defined
889 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
891 * GDB now supports access to vector registers on S/390 GNU/Linux
894 * Removed command line options
896 -xdb HP-UX XDB compatibility mode.
898 * Removed targets and native configurations
900 HP/PA running HP-UX hppa*-*-hpux*
901 Itanium running HP-UX ia64-*-hpux*
903 * New configure options
906 This configure option allows the user to build GDB with support for
907 Intel Processor Trace (default: auto). This requires libipt.
909 --with-libipt-prefix=PATH
910 Specify the path to the version of libipt that GDB should use.
911 $PATH/include should contain the intel-pt.h header and
912 $PATH/lib should contain the libipt.so library.
914 *** Changes in GDB 7.9.1
918 ** Xmethods can now specify a result type.
920 *** Changes in GDB 7.9
922 * GDB now supports hardware watchpoints on x86 GNU Hurd.
926 ** You can now access frame registers from Python scripts.
927 ** New attribute 'producer' for gdb.Symtab objects.
928 ** gdb.Objfile objects have a new attribute "progspace",
929 which is the gdb.Progspace object of the containing program space.
930 ** gdb.Objfile objects have a new attribute "owner".
931 ** gdb.Objfile objects have a new attribute "build_id",
932 which is the build ID generated when the file was built.
933 ** gdb.Objfile objects have a new method "add_separate_debug_file".
934 ** A new event "gdb.clear_objfiles" has been added, triggered when
935 selecting a new file to debug.
936 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
937 ** New function gdb.lookup_objfile.
939 New events which are triggered when GDB modifies the state of the
942 ** gdb.events.inferior_call_pre: Function call is about to be made.
943 ** gdb.events.inferior_call_post: Function call has just been made.
944 ** gdb.events.memory_changed: A memory location has been altered.
945 ** gdb.events.register_changed: A register has been altered.
947 * New Python-based convenience functions:
949 ** $_caller_is(name [, number_of_frames])
950 ** $_caller_matches(regexp [, number_of_frames])
951 ** $_any_caller_is(name [, number_of_frames])
952 ** $_any_caller_matches(regexp [, number_of_frames])
954 * GDB now supports the compilation and injection of source code into
955 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
956 to compile the source code to object code, and if successful, inject
957 and execute that code within the current context of the inferior.
958 Currently the C language is supported. The commands used to
959 interface with this new feature are:
961 compile code [-raw|-r] [--] [source code]
962 compile file [-raw|-r] filename
966 demangle [-l language] [--] name
967 Demangle "name" in the specified language, or the current language
968 if elided. This command is renamed from the "maint demangle" command.
969 The latter is kept as a no-op to avoid "maint demangle" being interpreted
970 as "maint demangler-warning".
972 queue-signal signal-name-or-number
973 Queue a signal to be delivered to the thread when it is resumed.
975 add-auto-load-scripts-directory directory
976 Add entries to the list of directories from which to load auto-loaded
979 maint print user-registers
980 List all currently available "user" registers.
982 compile code [-r|-raw] [--] [source code]
983 Compile, inject, and execute in the inferior the executable object
984 code produced by compiling the provided source code.
986 compile file [-r|-raw] filename
987 Compile and inject into the inferior the executable object code
988 produced by compiling the source code stored in the filename
991 * On resume, GDB now always passes the signal the program had stopped
992 for to the thread the signal was sent to, even if the user changed
993 threads before resuming. Previously GDB would often (but not
994 always) deliver the signal to the thread that happens to be current
997 * Conversely, the "signal" command now consistently delivers the
998 requested signal to the current thread. GDB now asks for
999 confirmation if the program had stopped for a signal and the user
1000 switched threads meanwhile.
1002 * "breakpoint always-inserted" modes "off" and "auto" merged.
1004 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
1005 won't remove breakpoints from the target until all threads stop,
1006 even in non-stop mode. The "auto" mode has been removed, and "off"
1007 is now the default mode.
1011 set debug symbol-lookup
1012 show debug symbol-lookup
1013 Control display of debugging info regarding symbol lookup.
1017 ** The -list-thread-groups command outputs an exit-code field for
1018 inferiors that have exited.
1022 MIPS SDE mips*-sde*-elf*
1026 Support for these obsolete configurations has been removed.
1028 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
1029 SGI Irix-5.x mips-*-irix5*
1030 SGI Irix-6.x mips-*-irix6*
1031 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
1032 VAX running Ultrix vax-*-ultrix*
1034 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1035 and "assf"), have been removed. Use the "sharedlibrary" command, or
1036 its alias "share", instead.
1038 *** Changes in GDB 7.8
1040 * New command line options
1043 This is an alias for the --data-directory option.
1045 * GDB supports printing and modifying of variable length automatic arrays
1046 as specified in ISO C99.
1048 * The ARM simulator now supports instruction level tracing
1049 with or without disassembly.
1053 GDB now has support for scripting using Guile. Whether this is
1054 available is determined at configure time.
1055 Guile version 2.0 or greater is required.
1056 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
1058 * New commands (for set/show, see "New options" below)
1062 Invoke CODE by passing it to the Guile interpreter.
1066 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
1068 info auto-load guile-scripts [regexp]
1069 Print the list of automatically loaded Guile scripts.
1071 * The source command is now capable of sourcing Guile scripts.
1072 This feature is dependent on the debugger being built with Guile support.
1076 set print symbol-loading (off|brief|full)
1077 show print symbol-loading
1078 Control whether to print informational messages when loading symbol
1079 information for a file. The default is "full", but when debugging
1080 programs with large numbers of shared libraries the amount of output
1081 becomes less useful.
1083 set guile print-stack (none|message|full)
1084 show guile print-stack
1085 Show a stack trace when an error is encountered in a Guile script.
1087 set auto-load guile-scripts (on|off)
1088 show auto-load guile-scripts
1089 Control auto-loading of Guile script files.
1091 maint ada set ignore-descriptive-types (on|off)
1092 maint ada show ignore-descriptive-types
1093 Control whether the debugger should ignore descriptive types in Ada
1094 programs. The default is not to ignore the descriptive types. See
1095 the user manual for more details on descriptive types and the intended
1096 usage of this option.
1098 set auto-connect-native-target
1100 Control whether GDB is allowed to automatically connect to the
1101 native target for the run, attach, etc. commands when not connected
1102 to any target yet. See also "target native" below.
1104 set record btrace replay-memory-access (read-only|read-write)
1105 show record btrace replay-memory-access
1106 Control what memory accesses are allowed during replay.
1108 maint set target-async (on|off)
1109 maint show target-async
1110 This controls whether GDB targets operate in synchronous or
1111 asynchronous mode. Normally the default is asynchronous, if it is
1112 available; but this can be changed to more easily debug problems
1113 occurring only in synchronous mode.
1115 set mi-async (on|off)
1117 Control whether MI asynchronous mode is preferred. This supersedes
1118 "set target-async" of previous GDB versions.
1120 * "set target-async" is deprecated as a CLI option and is now an alias
1121 for "set mi-async" (only puts MI into async mode).
1123 * Background execution commands (e.g., "c&", "s&", etc.) are now
1124 possible ``out of the box'' if the target supports them. Previously
1125 the user would need to explicitly enable the possibility with the
1126 "set target-async on" command.
1128 * New features in the GDB remote stub, GDBserver
1130 ** New option --debug-format=option1[,option2,...] allows one to add
1131 additional text to each output. At present only timestamps
1132 are supported: --debug-format=timestamps.
1133 Timestamps can also be turned on with the
1134 "monitor set debug-format timestamps" command from GDB.
1136 * The 'record instruction-history' command now starts counting instructions
1137 at one. This also affects the instruction ranges reported by the
1138 'record function-call-history' command when given the /i modifier.
1140 * The command 'record function-call-history' supports a new modifier '/c' to
1141 indent the function names based on their call stack depth.
1142 The fields for the '/i' and '/l' modifier have been reordered.
1143 The source line range is now prefixed with 'at'.
1144 The instruction range is now prefixed with 'inst'.
1145 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1146 "record instruction-history" and "list" commands.
1148 * The ranges given as arguments to the 'record function-call-history' and
1149 'record instruction-history' commands are now inclusive.
1151 * The btrace record target now supports the 'record goto' command.
1152 For locations inside the execution trace, the back trace is computed
1153 based on the information stored in the execution trace.
1155 * The btrace record target supports limited reverse execution and replay.
1156 The target does not record data and therefore does not allow reading
1157 memory or registers.
1159 * The "catch syscall" command now works on s390*-linux* targets.
1161 * The "compare-sections" command is no longer specific to target
1162 remote. It now works with all targets.
1164 * All native targets are now consistently called "native".
1165 Consequently, the "target child", "target GNU", "target djgpp",
1166 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1167 commands have been replaced with "target native". The QNX/NTO port
1168 leaves the "procfs" target in place and adds a "native" target for
1169 consistency with other ports. The impact on users should be minimal
1170 as these commands previously either throwed an error, or were
1171 no-ops. The target's name is visible in the output of the following
1172 commands: "help target", "info target", "info files", "maint print
1175 * The "target native" command now connects to the native target. This
1176 can be used to launch native programs even when "set
1177 auto-connect-native-target" is set to off.
1179 * GDB now supports access to Intel MPX registers on GNU/Linux.
1181 * Support for Intel AVX-512 registers on GNU/Linux.
1182 Support displaying and modifying Intel AVX-512 registers
1183 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1185 * New remote packets
1187 qXfer:btrace:read's annex
1188 The qXfer:btrace:read packet supports a new annex 'delta' to read
1189 branch trace incrementally.
1193 ** Valid Python operations on gdb.Value objects representing
1194 structs/classes invoke the corresponding overloaded operators if
1196 ** New `Xmethods' feature in the Python API. Xmethods are
1197 additional methods or replacements for existing methods of a C++
1198 class. This feature is useful for those cases where a method
1199 defined in C++ source code could be inlined or optimized out by
1200 the compiler, making it unavailable to GDB.
1203 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1205 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1206 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1207 its alias "share", instead.
1209 * The commands "set remotebaud" and "show remotebaud" are no longer
1210 supported. Use "set serial baud" and "show serial baud" (respectively)
1215 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1216 target-async". The latter is left as a deprecated alias of the
1217 former for backward compatibility. If the target supports it,
1218 CLI background execution commands are now always possible by
1219 default, independently of whether the frontend stated a
1220 preference for asynchronous execution with "-gdb-set mi-async".
1221 Previously "-gdb-set target-async off" affected both MI execution
1222 commands and CLI execution commands.
1224 *** Changes in GDB 7.7
1226 * Improved support for process record-replay and reverse debugging on
1227 arm*-linux* targets. Support for thumb32 and syscall instruction
1228 recording has been added.
1230 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1232 * GDB now supports Fission DWP file format version 2.
1233 http://gcc.gnu.org/wiki/DebugFission
1235 * New convenience function "$_isvoid", to check whether an expression
1236 is void. A void expression is an expression where the type of the
1237 result is "void". For example, some convenience variables may be
1238 "void" when evaluated (e.g., "$_exitcode" before the execution of
1239 the program being debugged; or an undefined convenience variable).
1240 Another example, when calling a function whose return type is
1243 * The "maintenance print objfiles" command now takes an optional regexp.
1245 * The "catch syscall" command now works on arm*-linux* targets.
1247 * GDB now consistently shows "<not saved>" when printing values of
1248 registers the debug info indicates have not been saved in the frame
1249 and there's nowhere to retrieve them from
1250 (callee-saved/call-clobbered registers):
1255 (gdb) info registers rax
1258 Before, the former would print "<optimized out>", and the latter
1259 "*value not available*".
1261 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1266 ** Frame filters and frame decorators have been added.
1267 ** Temporary breakpoints are now supported.
1268 ** Line tables representation has been added.
1269 ** New attribute 'parent_type' for gdb.Field objects.
1270 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1271 ** New attribute 'name' for gdb.Type objects.
1275 Nios II ELF nios2*-*-elf
1276 Nios II GNU/Linux nios2*-*-linux
1277 Texas Instruments MSP430 msp430*-*-elf
1279 * Removed native configurations
1281 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1282 been removed. ELF variants of these configurations are kept supported.
1284 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1285 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1286 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1287 i[34567]86-*-openbsd3.[0-3]
1288 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1289 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1290 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1294 Like "catch throw", but catches a re-thrown exception.
1295 maint check-psymtabs
1296 Renamed from old "maint check-symtabs".
1298 Perform consistency checks on symtabs.
1299 maint expand-symtabs
1300 Expand symtabs matching an optional regexp.
1303 Display the details of GDB configure-time options.
1305 maint set|show per-command
1306 maint set|show per-command space
1307 maint set|show per-command time
1308 maint set|show per-command symtab
1309 Enable display of per-command gdb resource usage.
1311 remove-symbol-file FILENAME
1312 remove-symbol-file -a ADDRESS
1313 Remove a symbol file added via add-symbol-file. The file to remove
1314 can be identified by its filename or by an address that lies within
1315 the boundaries of this symbol file in memory.
1318 info exceptions REGEXP
1319 Display the list of Ada exceptions defined in the program being
1320 debugged. If provided, only the exceptions whose names match REGEXP
1325 set debug symfile off|on
1327 Control display of debugging info regarding reading symbol files and
1328 symbol tables within those files
1330 set print raw frame-arguments
1331 show print raw frame-arguments
1332 Set/show whether to print frame arguments in raw mode,
1333 disregarding any defined pretty-printers.
1335 set remote trace-status-packet
1336 show remote trace-status-packet
1337 Set/show the use of remote protocol qTStatus packet.
1341 Control display of debugging messages related to Nios II targets.
1345 Control whether target-assisted range stepping is enabled.
1347 set startup-with-shell
1348 show startup-with-shell
1349 Specifies whether Unix child processes are started via a shell or
1354 Use the target memory cache for accesses to the code segment. This
1355 improves performance of remote debugging (particularly disassembly).
1357 * You can now use a literal value 'unlimited' for options that
1358 interpret 0 or -1 as meaning "unlimited". E.g., "set
1359 trace-buffer-size unlimited" is now an alias for "set
1360 trace-buffer-size -1" and "set height unlimited" is now an alias for
1363 * The "set debug symtab-create" debugging option of GDB has been changed to
1364 accept a verbosity level. 0 means "off", 1 provides basic debugging
1365 output, and values of 2 or greater provides more verbose output.
1367 * New command-line options
1369 Display the details of GDB configure-time options.
1371 * The command 'tsave' can now support new option '-ctf' to save trace
1372 buffer in Common Trace Format.
1374 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1377 * GDB now implements the the C++ 'typeid' operator.
1379 * The new convenience variable $_exception holds the exception being
1380 thrown or caught at an exception-related catchpoint.
1382 * The exception-related catchpoints, like "catch throw", now accept a
1383 regular expression which can be used to filter exceptions by type.
1385 * The new convenience variable $_exitsignal is automatically set to
1386 the terminating signal number when the program being debugged dies
1387 due to an uncaught signal.
1391 ** All MI commands now accept an optional "--language" option.
1392 Support for this feature can be verified by using the "-list-features"
1393 command, which should contain "language-option".
1395 ** The new command -info-gdb-mi-command allows the user to determine
1396 whether a GDB/MI command is supported or not.
1398 ** The "^error" result record returned when trying to execute an undefined
1399 GDB/MI command now provides a variable named "code" whose content is the
1400 "undefined-command" error code. Support for this feature can be verified
1401 by using the "-list-features" command, which should contain
1402 "undefined-command-error-code".
1404 ** The -trace-save MI command can optionally save trace buffer in Common
1407 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1409 ** The command -data-list-register-values now accepts an optional
1410 "--skip-unavailable" option. When used, only the available registers
1413 ** The new command -trace-frame-collected dumps collected variables,
1414 computed expressions, tvars, memory and registers in a traceframe.
1416 ** The commands -stack-list-locals, -stack-list-arguments and
1417 -stack-list-variables now accept an option "--skip-unavailable".
1418 When used, only the available locals or arguments are displayed.
1420 ** The -exec-run command now accepts an optional "--start" option.
1421 When used, the command follows the same semantics as the "start"
1422 command, stopping the program's execution at the start of its
1423 main subprogram. Support for this feature can be verified using
1424 the "-list-features" command, which should contain
1425 "exec-run-start-option".
1427 ** The new commands -catch-assert and -catch-exceptions insert
1428 catchpoints stopping the program when Ada exceptions are raised.
1430 ** The new command -info-ada-exceptions provides the equivalent of
1431 the new "info exceptions" command.
1433 * New system-wide configuration scripts
1434 A GDB installation now provides scripts suitable for use as system-wide
1435 configuration scripts for the following systems:
1439 * GDB now supports target-assigned range stepping with remote targets.
1440 This improves the performance of stepping source lines by reducing
1441 the number of control packets from/to GDB. See "New remote packets"
1444 * GDB now understands the element 'tvar' in the XML traceframe info.
1445 It has the id of the collected trace state variables.
1447 * On S/390 targets that provide the transactional-execution feature,
1448 the program interruption transaction diagnostic block (TDB) is now
1449 represented as a number of additional "registers" in GDB.
1451 * New remote packets
1455 The vCont packet supports a new 'r' action, that tells the remote
1456 stub to step through an address range itself, without GDB
1457 involvemement at each single-step.
1459 qXfer:libraries-svr4:read's annex
1460 The previously unused annex of the qXfer:libraries-svr4:read packet
1461 is now used to support passing an argument list. The remote stub
1462 reports support for this argument list to GDB's qSupported query.
1463 The defined arguments are "start" and "prev", used to reduce work
1464 necessary for library list updating, resulting in significant
1467 * New features in the GDB remote stub, GDBserver
1469 ** GDBserver now supports target-assisted range stepping. Currently
1470 enabled on x86/x86_64 GNU/Linux targets.
1472 ** GDBserver now adds element 'tvar' in the XML in the reply to
1473 'qXfer:traceframe-info:read'. It has the id of the collected
1474 trace state variables.
1476 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1479 * New 'z' formatter for printing and examining memory, this displays the
1480 value as hexadecimal zero padded on the left to the size of the type.
1482 * GDB can now use Windows x64 unwinding data.
1484 * The "set remotebaud" command has been replaced by "set serial baud".
1485 Similarly, "show remotebaud" has been replaced by "show serial baud".
1486 The "set remotebaud" and "show remotebaud" commands are still available
1487 to provide backward compatibility with older versions of GDB.
1489 *** Changes in GDB 7.6
1491 * Target record has been renamed to record-full.
1492 Record/replay is now enabled with the "record full" command.
1493 This also affects settings that are associated with full record/replay
1494 that have been moved from "set/show record" to "set/show record full":
1496 set|show record full insn-number-max
1497 set|show record full stop-at-limit
1498 set|show record full memory-query
1500 * A new record target "record-btrace" has been added. The new target
1501 uses hardware support to record the control-flow of a process. It
1502 does not support replaying the execution, but it implements the
1503 below new commands for investigating the recorded execution log.
1504 This new recording method can be enabled using:
1508 The "record-btrace" target is only available on Intel Atom processors
1509 and requires a Linux kernel 2.6.32 or later.
1511 * Two new commands have been added for record/replay to give information
1512 about the recorded execution without having to replay the execution.
1513 The commands are only supported by "record btrace".
1515 record instruction-history prints the execution history at
1516 instruction granularity
1518 record function-call-history prints the execution history at
1519 function granularity
1521 * New native configurations
1523 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1524 FreeBSD/powerpc powerpc*-*-freebsd
1525 x86_64/Cygwin x86_64-*-cygwin*
1526 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1530 ARM AArch64 aarch64*-*-elf
1531 ARM AArch64 GNU/Linux aarch64*-*-linux
1532 Lynx 178 PowerPC powerpc-*-lynx*178
1533 x86_64/Cygwin x86_64-*-cygwin*
1534 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1536 * If the configured location of system.gdbinit file (as given by the
1537 --with-system-gdbinit option at configure time) is in the
1538 data-directory (as specified by --with-gdb-datadir at configure
1539 time) or in one of its subdirectories, then GDB will look for the
1540 system-wide init file in the directory specified by the
1541 --data-directory command-line option.
1543 * New command line options:
1545 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1546 other initialization files, unlike -nx which disables all of them.
1548 * Removed command line options
1550 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1553 * The 'ptype' and 'whatis' commands now accept an argument to control
1556 * 'info proc' now works on some core files.
1560 ** Vectors can be created with gdb.Type.vector.
1562 ** Python's atexit.register now works in GDB.
1564 ** Types can be pretty-printed via a Python API.
1566 ** Python 3 is now supported (in addition to Python 2.4 or later)
1568 ** New class gdb.Architecture exposes GDB's internal representation
1569 of architecture in the Python API.
1571 ** New method Frame.architecture returns the gdb.Architecture object
1572 corresponding to the frame's architecture.
1574 * New Python-based convenience functions:
1576 ** $_memeq(buf1, buf2, length)
1577 ** $_streq(str1, str2)
1579 ** $_regex(str, regex)
1581 * The 'cd' command now defaults to using '~' (the home directory) if not
1584 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1585 default for GCC since November 2000.
1587 * The command 'forward-search' can now be abbreviated as 'fo'.
1589 * The command 'info tracepoints' can now display 'installed on target'
1590 or 'not installed on target' for each non-pending location of tracepoint.
1592 * New configure options
1594 --enable-libmcheck/--disable-libmcheck
1595 By default, development versions are built with -lmcheck on hosts
1596 that support it, in order to help track memory corruption issues.
1597 Release versions, on the other hand, are built without -lmcheck
1598 by default. The --enable-libmcheck/--disable-libmcheck configure
1599 options allow the user to override that default.
1600 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1601 This configure option allows the user to build GDB with
1602 libbabeltrace using which GDB can read Common Trace Format data.
1604 * New commands (for set/show, see "New options" below)
1607 Catch signals. This is similar to "handle", but allows commands and
1608 conditions to be attached.
1611 List the BFDs known to GDB.
1613 python-interactive [command]
1615 Start a Python interactive prompt, or evaluate the optional command
1616 and print the result of expressions.
1619 "py" is a new alias for "python".
1621 enable type-printer [name]...
1622 disable type-printer [name]...
1623 Enable or disable type printers.
1627 ** For the Renesas Super-H architecture, the "regs" command has been removed
1628 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1633 set print type methods (on|off)
1634 show print type methods
1635 Control whether method declarations are displayed by "ptype".
1636 The default is to show them.
1638 set print type typedefs (on|off)
1639 show print type typedefs
1640 Control whether typedef definitions are displayed by "ptype".
1641 The default is to show them.
1643 set filename-display basename|relative|absolute
1644 show filename-display
1645 Control the way in which filenames is displayed.
1646 The default is "relative", which preserves previous behavior.
1648 set trace-buffer-size
1649 show trace-buffer-size
1650 Request target to change the size of trace buffer.
1652 set remote trace-buffer-size-packet auto|on|off
1653 show remote trace-buffer-size-packet
1654 Control the use of the remote protocol `QTBuffer:size' packet.
1658 Control display of debugging messages related to ARM AArch64.
1661 set debug coff-pe-read
1662 show debug coff-pe-read
1663 Control display of debugging messages related to reading of COFF/PE
1668 Control display of debugging messages related to Mach-O symbols
1671 set debug notification
1672 show debug notification
1673 Control display of debugging info for async remote notification.
1677 ** Command parameter changes are now notified using new async record
1678 "=cmd-param-changed".
1679 ** Trace frame changes caused by command "tfind" are now notified using
1680 new async record "=traceframe-changed".
1681 ** The creation, deletion and modification of trace state variables
1682 are now notified using new async records "=tsv-created",
1683 "=tsv-deleted" and "=tsv-modified".
1684 ** The start and stop of process record are now notified using new
1685 async record "=record-started" and "=record-stopped".
1686 ** Memory changes are now notified using new async record
1688 ** The data-disassemble command response will include a "fullname" field
1689 containing the absolute file name when source has been requested.
1690 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1691 command, to allow pattern filling of memory areas.
1692 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1693 library load/unload events.
1694 ** The response to breakpoint commands and breakpoint async records
1695 includes an "installed" field containing a boolean state about each
1696 non-pending tracepoint location is whether installed on target or not.
1697 ** Output of the "-trace-status" command includes a "trace-file" field
1698 containing the name of the trace file being examined. This field is
1699 optional, and only present when examining a trace file.
1700 ** The "fullname" field is now always present along with the "file" field,
1701 even if the file cannot be found by GDB.
1703 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1704 You must have the LZMA library available when configuring GDB for this
1705 feature to be enabled. For more information, see:
1706 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1708 * New remote packets
1711 Set the size of trace buffer. The remote stub reports support for this
1712 packet to gdb's qSupported query.
1715 Enable Branch Trace Store (BTS)-based branch tracing for the current
1716 thread. The remote stub reports support for this packet to gdb's
1720 Disable branch tracing for the current thread. The remote stub reports
1721 support for this packet to gdb's qSupported query.
1724 Read the traced branches for the current thread. The remote stub
1725 reports support for this packet to gdb's qSupported query.
1727 *** Changes in GDB 7.5
1729 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1730 for more x32 ABI info.
1732 * GDB now supports access to MIPS DSP registers on Linux targets.
1734 * GDB now supports debugging microMIPS binaries.
1736 * The "info os" command on GNU/Linux can now display information on
1737 several new classes of objects managed by the operating system:
1738 "info os procgroups" lists process groups
1739 "info os files" lists file descriptors
1740 "info os sockets" lists internet-domain sockets
1741 "info os shm" lists shared-memory regions
1742 "info os semaphores" lists semaphores
1743 "info os msg" lists message queues
1744 "info os modules" lists loaded kernel modules
1746 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1747 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1748 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1749 options and inspect the probe arguments using the new $_probe_arg family
1750 of convenience variables. You can obtain more information about SystemTap
1751 in <http://sourceware.org/systemtap/>.
1753 * GDB now supports reversible debugging on ARM, it allows you to
1754 debug basic ARM and THUMB instructions, and provides
1755 record/replay support.
1757 * The option "symbol-reloading" has been deleted as it is no longer used.
1761 ** GDB commands implemented in Python can now be put in command class
1764 ** The "maint set python print-stack on|off" is now deleted.
1766 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1767 apply "flag enum"-style pretty-printing to any enum.
1769 ** gdb.lookup_symbol can now work when there is no current frame.
1771 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1772 the source at which the symbol was defined.
1774 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1775 method 'value'. The former indicates whether the symbol needs a
1776 frame in order to compute its value, and the latter computes the
1779 ** A new method 'referenced_value' on gdb.Value objects which can
1780 dereference pointer as well as C++ reference values.
1782 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1783 which return the global and static blocks (as gdb.Block objects),
1784 of the underlying symbol table, respectively.
1786 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1787 object associated with a PC value.
1789 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1790 of the address range occupied by code for the current source line.
1792 * Go language support.
1793 GDB now supports debugging programs written in the Go programming
1796 * GDBserver now supports stdio connections.
1797 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1799 * The binary "gdbtui" can no longer be built or installed.
1800 Use "gdb -tui" instead.
1802 * GDB will now print "flag" enums specially. A flag enum is one where
1803 all the enumerator values have no bits in common when pairwise
1804 "and"ed. When printing a value whose type is a flag enum, GDB will
1805 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1806 (gdb) print (enum E) 3
1809 * The filename part of a linespec will now match trailing components
1810 of a source file name. For example, "break gcc/expr.c:1000" will
1811 now set a breakpoint in build/gcc/expr.c, but not
1812 build/libcpp/expr.c.
1814 * The "info proc" and "generate-core-file" commands will now also
1815 work on remote targets connected to GDBserver on Linux.
1817 * The command "info catch" has been removed. It has been disabled
1818 since December 2007.
1820 * The "catch exception" and "catch assert" commands now accept
1821 a condition at the end of the command, much like the "break"
1822 command does. For instance:
1824 (gdb) catch exception Constraint_Error if Barrier = True
1826 Previously, it was possible to add a condition to such catchpoints,
1827 but it had to be done as a second step, after the catchpoint had been
1828 created, using the "condition" command.
1830 * The "info static-tracepoint-marker" command will now also work on
1831 native Linux targets with in-process agent.
1833 * GDB can now set breakpoints on inlined functions.
1835 * The .gdb_index section has been updated to include symbols for
1836 inlined functions. GDB will ignore older .gdb_index sections by
1837 default, which could cause symbol files to be loaded more slowly
1838 until their .gdb_index sections can be recreated. The new command
1839 "set use-deprecated-index-sections on" will cause GDB to use any older
1840 .gdb_index sections it finds. This will restore performance, but the
1841 ability to set breakpoints on inlined functions will be lost in symbol
1842 files with older .gdb_index sections.
1844 The .gdb_index section has also been updated to record more information
1845 about each symbol. This speeds up the "info variables", "info functions"
1846 and "info types" commands when used with programs having the .gdb_index
1847 section, as well as speeding up debugging with shared libraries using
1848 the .gdb_index section.
1850 * Ada support for GDB/MI Variable Objects has been added.
1852 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1857 ** New command -info-os is the MI equivalent of "info os".
1859 ** Output logs ("set logging" and related) now include MI output.
1863 ** "set use-deprecated-index-sections on|off"
1864 "show use-deprecated-index-sections on|off"
1865 Controls the use of deprecated .gdb_index sections.
1867 ** "catch load" and "catch unload" can be used to stop when a shared
1868 library is loaded or unloaded, respectively.
1870 ** "enable count" can be used to auto-disable a breakpoint after
1873 ** "info vtbl" can be used to show the virtual method tables for
1874 C++ and Java objects.
1876 ** "explore" and its sub commands "explore value" and "explore type"
1877 can be used to recursively explore values and types of
1878 expressions. These commands are available only if GDB is
1879 configured with '--with-python'.
1881 ** "info auto-load" shows status of all kinds of auto-loaded files,
1882 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1883 sequences of commands files, "info auto-load python-scripts"
1884 shows status of auto-loading Python script files,
1885 "info auto-load local-gdbinit" shows status of loading init file
1886 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1887 status of inferior specific thread debugging shared library loading.
1889 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1890 and "show auto-load-scripts" commands have been deprecated, use their
1891 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1892 and "show auto-load python-scripts" counterparts instead.
1894 ** "dprintf location,format,args..." creates a dynamic printf, which
1895 is basically a breakpoint that does a printf and immediately
1896 resumes your program's execution, so it is like a printf that you
1897 can insert dynamically at runtime instead of at compiletime.
1899 ** "set print symbol"
1901 Controls whether GDB attempts to display the symbol, if any,
1902 corresponding to addresses it prints. This defaults to "on", but
1903 you can set it to "off" to restore GDB's previous behavior.
1905 * Deprecated commands
1907 ** For the Renesas Super-H architecture, the "regs" command has been
1908 deprecated, and "info all-registers" should be used instead.
1912 Renesas RL78 rl78-*-elf
1913 HP OpenVMS ia64 ia64-hp-openvms*
1915 * GDBserver supports evaluation of breakpoint conditions. When
1916 support is advertised by GDBserver, GDB may be told to send the
1917 breakpoint conditions in bytecode form to GDBserver. GDBserver
1918 will only report the breakpoint trigger to GDB when its condition
1923 set mips compression
1924 show mips compression
1925 Select the compressed ISA encoding used in functions that have no symbol
1926 information available. The encoding can be set to either of:
1929 and is updated automatically from ELF file flags if available.
1931 set breakpoint condition-evaluation
1932 show breakpoint condition-evaluation
1933 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1934 GDBserver ("target"). Default option "auto" chooses the most efficient
1936 This option can improve debugger efficiency depending on the speed of the
1940 Disable auto-loading globally.
1943 Show auto-loading setting of all kinds of auto-loaded files.
1945 set auto-load gdb-scripts on|off
1946 show auto-load gdb-scripts
1947 Control auto-loading of GDB canned sequences of commands files.
1949 set auto-load python-scripts on|off
1950 show auto-load python-scripts
1951 Control auto-loading of Python script files.
1953 set auto-load local-gdbinit on|off
1954 show auto-load local-gdbinit
1955 Control loading of init file (.gdbinit) from current directory.
1957 set auto-load libthread-db on|off
1958 show auto-load libthread-db
1959 Control auto-loading of inferior specific thread debugging shared library.
1961 set auto-load scripts-directory <dir1>[:<dir2>...]
1962 show auto-load scripts-directory
1963 Set a list of directories from which to load auto-loaded scripts.
1964 Automatically loaded Python scripts and GDB scripts are located in one
1965 of the directories listed by this option.
1966 The delimiter (':' above) may differ according to the host platform.
1968 set auto-load safe-path <dir1>[:<dir2>...]
1969 show auto-load safe-path
1970 Set a list of directories from which it is safe to auto-load files.
1971 The delimiter (':' above) may differ according to the host platform.
1973 set debug auto-load on|off
1974 show debug auto-load
1975 Control display of debugging info for auto-loading the files above.
1977 set dprintf-style gdb|call|agent
1979 Control the way in which a dynamic printf is performed; "gdb"
1980 requests a GDB printf command, while "call" causes dprintf to call a
1981 function in the inferior. "agent" requests that the target agent
1982 (such as GDBserver) do the printing.
1984 set dprintf-function <expr>
1985 show dprintf-function
1986 set dprintf-channel <expr>
1987 show dprintf-channel
1988 Set the function and optional first argument to the call when using
1989 the "call" style of dynamic printf.
1991 set disconnected-dprintf on|off
1992 show disconnected-dprintf
1993 Control whether agent-style dynamic printfs continue to be in effect
1994 after GDB disconnects.
1996 * New configure options
1998 --with-auto-load-dir
1999 Configure default value for the 'set auto-load scripts-directory'
2000 setting above. It defaults to '$debugdir:$datadir/auto-load',
2001 $debugdir representing global debugging info directories (available
2002 via 'show debug-file-directory') and $datadir representing GDB's data
2003 directory (available via 'show data-directory').
2005 --with-auto-load-safe-path
2006 Configure default value for the 'set auto-load safe-path' setting
2007 above. It defaults to the --with-auto-load-dir setting.
2009 --without-auto-load-safe-path
2010 Set 'set auto-load safe-path' to '/', effectively disabling this
2013 * New remote packets
2015 z0/z1 conditional breakpoints extension
2017 The z0/z1 breakpoint insertion packets have been extended to carry
2018 a list of conditional expressions over to the remote stub depending on the
2019 condition evaluation mode. The use of this extension can be controlled
2020 via the "set remote conditional-breakpoints-packet" command.
2024 Specify the signals which the remote stub may pass to the debugged
2025 program without GDB involvement.
2027 * New command line options
2029 --init-command=FILE, -ix Like --command, -x but execute it
2030 before loading inferior.
2031 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
2032 execute it before loading inferior.
2034 *** Changes in GDB 7.4
2036 * GDB now handles ambiguous linespecs more consistently; the existing
2037 FILE:LINE support has been expanded to other types of linespecs. A
2038 breakpoint will now be set on all matching locations in all
2039 inferiors, and locations will be added or removed according to
2042 * GDB now allows you to skip uninteresting functions and files when
2043 stepping with the "skip function" and "skip file" commands.
2045 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
2046 and "show remote hardware-watchpoint-length-limit". These allows to
2047 set or show the maximum length limit (in bytes) of a remote
2048 target hardware watchpoint.
2050 This allows e.g. to use "unlimited" hardware watchpoints with the
2051 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
2052 watchpoints are slower than real hardware watchpoints but are
2053 significantly faster than gdb software watchpoints.
2057 ** The register_pretty_printer function in module gdb.printing now takes
2058 an optional `replace' argument. If True, the new printer replaces any
2061 ** The "maint set python print-stack on|off" command has been
2062 deprecated and will be deleted in GDB 7.5.
2063 A new command: "set python print-stack none|full|message" has
2064 replaced it. Additionally, the default for "print-stack" is
2065 now "message", which just prints the error message without
2068 ** A prompt substitution hook (prompt_hook) is now available to the
2071 ** A new Python module, gdb.prompt has been added to the GDB Python
2072 modules library. This module provides functionality for
2073 escape sequences in prompts (used by set/show
2074 extended-prompt). These escape sequences are replaced by their
2075 corresponding value.
2077 ** Python commands and convenience-functions located in
2078 'data-directory'/python/gdb/command and
2079 'data-directory'/python/gdb/function are now automatically loaded
2082 ** Blocks now provide four new attributes. global_block and
2083 static_block will return the global and static blocks
2084 respectively. is_static and is_global are boolean attributes
2085 that indicate if the block is one of those two types.
2087 ** Symbols now provide the "type" attribute, the type of the symbol.
2089 ** The "gdb.breakpoint" function has been deprecated in favor of
2092 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2093 of a function. This class is based on the "finish" command
2094 available in the CLI.
2096 ** Type objects for struct and union types now allow access to
2097 the fields using standard Python dictionary (mapping) methods.
2098 For example, "some_type['myfield']" now works, as does
2099 "some_type.items()".
2101 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2104 ** A new function, "deep_items" has been added to the gdb.types
2105 module in the GDB Python modules library. This function returns
2106 an iterator over the fields of a struct or union type. Unlike
2107 the standard Python "iteritems" method, it will recursively traverse
2108 any anonymous fields.
2112 ** "*stopped" events can report several new "reason"s, such as
2115 ** Breakpoint changes are now notified using new async records, like
2116 "=breakpoint-modified".
2118 ** New command -ada-task-info.
2120 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2121 $sdir specifies the default system locations of shared libraries.
2122 $pdir specifies the directory where the libpthread used by the application
2125 GDB no longer looks in $sdir and $pdir after it has searched the directories
2126 mentioned in libthread-db-search-path. If you want to search those
2127 directories, they must be specified in libthread-db-search-path.
2128 The default value of libthread-db-search-path on GNU/Linux and Solaris
2129 systems is now "$sdir:$pdir".
2131 $pdir is not supported by gdbserver, it is currently ignored.
2132 $sdir is supported by gdbserver.
2134 * New configure option --with-iconv-bin.
2135 When using the internationalization support like the one in the GNU C
2136 library, GDB will invoke the "iconv" program to get a list of supported
2137 character sets. If this program lives in a non-standard location, one can
2138 use this option to specify where to find it.
2140 * When natively debugging programs on PowerPC BookE processors running
2141 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2142 watchpoints, which specify a mask in addition to an address to watch.
2143 The mask specifies that some bits of an address (the bits which are
2144 reset in the mask) should be ignored when matching the address accessed
2145 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2146 section in the user manual for more details.
2148 * The new option --once causes GDBserver to stop listening for connections once
2149 the first connection is made. The listening port used by GDBserver will
2150 become available after that.
2152 * New commands "info macros" and "alias" have been added.
2154 * New function parameters suffix @entry specifies value of function parameter
2155 at the time the function got called. Entry values are available only since
2161 "!" is now an alias of the "shell" command.
2162 Note that no space is needed between "!" and SHELL COMMAND.
2166 watch EXPRESSION mask MASK_VALUE
2167 The watch command now supports the mask argument which allows creation
2168 of masked watchpoints, if the current architecture supports this feature.
2170 info auto-load-scripts [REGEXP]
2171 This command was formerly named "maintenance print section-scripts".
2172 It is now generally useful and is no longer a maintenance-only command.
2174 info macro [-all] [--] MACRO
2175 The info macro command has new options `-all' and `--'. The first for
2176 printing all definitions of a macro. The second for explicitly specifying
2177 the end of arguments and the beginning of the macro name in case the macro
2178 name starts with a hyphen.
2180 collect[/s] EXPRESSIONS
2181 The tracepoint collect command now takes an optional modifier "/s"
2182 that directs it to dereference pointer-to-character types and
2183 collect the bytes of memory up to a zero byte. The behavior is
2184 similar to what you see when you use the regular print command on a
2185 string. An optional integer following the "/s" sets a bound on the
2186 number of bytes that will be collected.
2189 The trace start command now interprets any supplied arguments as a
2190 note to be recorded with the trace run, with an effect similar to
2191 setting the variable trace-notes.
2194 The trace stop command now interprets any arguments as a note to be
2195 mentioned along with the tstatus report that the trace was stopped
2196 with a command. The effect is similar to setting the variable
2199 * Tracepoints can now be enabled and disabled at any time after a trace
2200 experiment has been started using the standard "enable" and "disable"
2201 commands. It is now possible to start a trace experiment with no enabled
2202 tracepoints; GDB will display a warning, but will allow the experiment to
2203 begin, assuming that tracepoints will be enabled as needed while the trace
2206 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2207 locations with 4-byte instructions, when they were previously
2208 limited to locations with instructions of 5 bytes or longer.
2212 set debug dwarf2-read
2213 show debug dwarf2-read
2214 Turns on or off display of debugging messages related to reading
2215 DWARF debug info. The default is off.
2217 set debug symtab-create
2218 show debug symtab-create
2219 Turns on or off display of debugging messages related to symbol table
2220 creation. The default is off.
2223 show extended-prompt
2224 Set the GDB prompt, and allow escape sequences to be inserted to
2225 display miscellaneous information (see 'help set extended-prompt'
2226 for the list of sequences). This prompt (and any information
2227 accessed through the escape sequences) is updated every time the
2228 prompt is displayed.
2230 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2231 show print entry-values
2232 Set printing of frame argument values at function entry. In some cases
2233 GDB can determine the value of function argument which was passed by the
2234 function caller, even if the value was modified inside the called function.
2236 set debug entry-values
2237 show debug entry-values
2238 Control display of debugging info for determining frame argument values at
2239 function entry and virtual tail call frames.
2241 set basenames-may-differ
2242 show basenames-may-differ
2243 Set whether a source file may have multiple base names.
2244 (A "base name" is the name of a file with the directory part removed.
2245 Example: The base name of "/home/user/hello.c" is "hello.c".)
2246 If set, GDB will canonicalize file names (e.g., expand symlinks)
2247 before comparing them. Canonicalization is an expensive operation,
2248 but it allows the same file be known by more than one base name.
2249 If not set (the default), all source files are assumed to have just
2250 one base name, and gdb will do file name comparisons more efficiently.
2256 Set a user name and notes for the current and any future trace runs.
2257 This is useful for long-running and/or disconnected traces, to
2258 inform others (or yourself) as to who is running the trace, supply
2259 contact information, or otherwise explain what is going on.
2261 set trace-stop-notes
2262 show trace-stop-notes
2263 Set a note attached to the trace run, that is displayed when the
2264 trace has been stopped by a tstop command. This is useful for
2265 instance as an explanation, if you are stopping a trace run that was
2266 started by someone else.
2268 * New remote packets
2272 Dynamically enable a tracepoint in a started trace experiment.
2276 Dynamically disable a tracepoint in a started trace experiment.
2280 Set the user and notes of the trace run.
2284 Query the current status of a tracepoint.
2288 Query the minimum length of instruction at which a fast tracepoint may
2291 * Dcache size (number of lines) and line-size are now runtime-configurable
2292 via "set dcache line" and "set dcache line-size" commands.
2296 Texas Instruments TMS320C6x tic6x-*-*
2300 Renesas RL78 rl78-*-elf
2302 *** Changes in GDB 7.3.1
2304 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2306 *** Changes in GDB 7.3
2308 * GDB has a new command: "thread find [REGEXP]".
2309 It finds the thread id whose name, target id, or thread extra info
2310 matches the given regular expression.
2312 * The "catch syscall" command now works on mips*-linux* targets.
2314 * The -data-disassemble MI command now supports modes 2 and 3 for
2315 dumping the instruction opcodes.
2317 * New command line options
2319 -data-directory DIR Specify DIR as the "data-directory".
2320 This is mostly for testing purposes.
2322 * The "maint set python auto-load on|off" command has been renamed to
2323 "set auto-load-scripts on|off".
2325 * GDB has a new command: "set directories".
2326 It is like the "dir" command except that it replaces the
2327 source path list instead of augmenting it.
2329 * GDB now understands thread names.
2331 On GNU/Linux, "info threads" will display the thread name as set by
2332 prctl or pthread_setname_np.
2334 There is also a new command, "thread name", which can be used to
2335 assign a name internally for GDB to display.
2338 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2339 has been integrated into GDB.
2343 ** The function gdb.Write now accepts an optional keyword 'stream'.
2344 This keyword, when provided, will direct the output to either
2345 stdout, stderr, or GDB's logging output.
2347 ** Parameters can now be be sub-classed in Python, and in particular
2348 you may implement the get_set_doc and get_show_doc functions.
2349 This improves how Parameter set/show documentation is processed
2350 and allows for more dynamic content.
2352 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2353 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2354 have an is_valid method.
2356 ** Breakpoints can now be sub-classed in Python, and in particular
2357 you may implement a 'stop' function that is executed each time
2358 the inferior reaches that breakpoint.
2360 ** New function gdb.lookup_global_symbol looks up a global symbol.
2362 ** GDB values in Python are now callable if the value represents a
2363 function. For example, if 'some_value' represents a function that
2364 takes two integer parameters and returns a value, you can call
2365 that function like so:
2367 result = some_value (10,20)
2369 ** Module gdb.types has been added.
2370 It contains a collection of utilities for working with gdb.Types objects:
2371 get_basic_type, has_field, make_enum_dict.
2373 ** Module gdb.printing has been added.
2374 It contains utilities for writing and registering pretty-printers.
2375 New classes: PrettyPrinter, SubPrettyPrinter,
2376 RegexpCollectionPrettyPrinter.
2377 New function: register_pretty_printer.
2379 ** New commands "info pretty-printers", "enable pretty-printer" and
2380 "disable pretty-printer" have been added.
2382 ** gdb.parameter("directories") is now available.
2384 ** New function gdb.newest_frame returns the newest frame in the
2387 ** The gdb.InferiorThread class has a new "name" attribute. This
2388 holds the thread's name.
2390 ** Python Support for Inferior events.
2391 Python scripts can add observers to be notified of events
2392 occurring in the process being debugged.
2393 The following events are currently supported:
2394 - gdb.events.cont Continue event.
2395 - gdb.events.exited Inferior exited event.
2396 - gdb.events.stop Signal received, and Breakpoint hit events.
2400 ** GDB now puts template parameters in scope when debugging in an
2401 instantiation. For example, if you have:
2403 template<int X> int func (void) { return X; }
2405 then if you step into func<5>, "print X" will show "5". This
2406 feature requires proper debuginfo support from the compiler; it
2407 was added to GCC 4.5.
2409 ** The motion commands "next", "finish", "until", and "advance" now
2410 work better when exceptions are thrown. In particular, GDB will
2411 no longer lose control of the inferior; instead, the GDB will
2412 stop the inferior at the point at which the exception is caught.
2413 This functionality requires a change in the exception handling
2414 code that was introduced in GCC 4.5.
2416 * GDB now follows GCC's rules on accessing volatile objects when
2417 reading or writing target state during expression evaluation.
2418 One notable difference to prior behavior is that "print x = 0"
2419 no longer generates a read of x; the value of the assignment is
2420 now always taken directly from the value being assigned.
2422 * GDB now has some support for using labels in the program's source in
2423 linespecs. For instance, you can use "advance label" to continue
2424 execution to a label.
2426 * GDB now has support for reading and writing a new .gdb_index
2427 section. This section holds a fast index of DWARF debugging
2428 information and can be used to greatly speed up GDB startup and
2429 operation. See the documentation for `save gdb-index' for details.
2431 * The "watch" command now accepts an optional "-location" argument.
2432 When used, this causes GDB to watch the memory referred to by the
2433 expression. Such a watchpoint is never deleted due to it going out
2436 * GDB now supports thread debugging of core dumps on GNU/Linux.
2438 GDB now activates thread debugging using the libthread_db library
2439 when debugging GNU/Linux core dumps, similarly to when debugging
2440 live processes. As a result, when debugging a core dump file, GDB
2441 is now able to display pthread_t ids of threads. For example, "info
2442 threads" shows the same output as when debugging the process when it
2443 was live. In earlier releases, you'd see something like this:
2446 * 1 LWP 6780 main () at main.c:10
2448 While now you see this:
2451 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2453 It is also now possible to inspect TLS variables when debugging core
2456 When debugging a core dump generated on a machine other than the one
2457 used to run GDB, you may need to point GDB at the correct
2458 libthread_db library with the "set libthread-db-search-path"
2459 command. See the user manual for more details on this command.
2461 * When natively debugging programs on PowerPC BookE processors running
2462 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2463 which stop execution of the inferior whenever it executes an instruction
2464 at any address within the specified range. See the "PowerPC Embedded"
2465 section in the user manual for more details.
2467 * New features in the GDB remote stub, GDBserver
2469 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2470 and i686 LynxOS (version 5.x).
2472 ** GDBserver is now supported on Blackfin Linux.
2474 * New native configurations
2476 ia64 HP-UX ia64-*-hpux*
2480 Analog Devices, Inc. Blackfin Processor bfin-*
2482 * Ada task switching is now supported on sparc-elf targets when
2483 debugging a program using the Ravenscar Profile. For more information,
2484 see the "Tasking Support when using the Ravenscar Profile" section
2485 in the GDB user manual.
2487 * Guile support was removed.
2489 * New features in the GNU simulator
2491 ** The --map-info flag lists all known core mappings.
2493 ** CFI flashes may be simulated via the "cfi" device.
2495 *** Changes in GDB 7.2
2497 * Shared library support for remote targets by default
2499 When GDB is configured for a generic, non-OS specific target, like
2500 for example, --target=arm-eabi or one of the many *-*-elf targets,
2501 GDB now queries remote stubs for loaded shared libraries using the
2502 `qXfer:libraries:read' packet. Previously, shared library support
2503 was always disabled for such configurations.
2507 ** Argument Dependent Lookup (ADL)
2509 In C++ ADL lookup directs function search to the namespaces of its
2510 arguments even if the namespace has not been imported.
2520 Here the compiler will search for `foo' in the namespace of 'b'
2521 and find A::foo. GDB now supports this. This construct is commonly
2522 used in the Standard Template Library for operators.
2524 ** Improved User Defined Operator Support
2526 In addition to member operators, GDB now supports lookup of operators
2527 defined in a namespace and imported with a `using' directive, operators
2528 defined in the global scope, operators imported implicitly from an
2529 anonymous namespace, and the ADL operators mentioned in the previous
2531 GDB now also supports proper overload resolution for all the previously
2532 mentioned flavors of operators.
2534 ** static const class members
2536 Printing of static const class members that are initialized in the
2537 class definition has been fixed.
2539 * Windows Thread Information Block access.
2541 On Windows targets, GDB now supports displaying the Windows Thread
2542 Information Block (TIB) structure. This structure is visible either
2543 by using the new command `info w32 thread-information-block' or, by
2544 dereferencing the new convenience variable named `$_tlb', a
2545 thread-specific pointer to the TIB. This feature is also supported
2546 when remote debugging using GDBserver.
2548 * Static tracepoints
2550 Static tracepoints are calls in the user program into a tracing
2551 library. One such library is a port of the LTTng kernel tracer to
2552 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2553 When debugging with GDBserver, GDB now supports combining the GDB
2554 tracepoint machinery with such libraries. For example: the user can
2555 use GDB to probe a static tracepoint marker (a call from the user
2556 program into the tracing library) with the new "strace" command (see
2557 "New commands" below). This creates a "static tracepoint" in the
2558 breakpoint list, that can be manipulated with the same feature set
2559 as fast and regular tracepoints. E.g., collect registers, local and
2560 global variables, collect trace state variables, and define
2561 tracepoint conditions. In addition, the user can collect extra
2562 static tracepoint marker specific data, by collecting the new
2563 $_sdata internal variable. When analyzing the trace buffer, you can
2564 inspect $_sdata like any other variable available to GDB. For more
2565 information, see the "Tracepoints" chapter in GDB user manual. New
2566 remote packets have been defined to support static tracepoints, see
2567 the "New remote packets" section below.
2569 * Better reconstruction of tracepoints after disconnected tracing
2571 GDB will attempt to download the original source form of tracepoint
2572 definitions when starting a trace run, and then will upload these
2573 upon reconnection to the target, resulting in a more accurate
2574 reconstruction of the tracepoints that are in use on the target.
2578 You can now exercise direct control over the ways that GDB can
2579 affect your program. For instance, you can disallow the setting of
2580 breakpoints, so that the program can run continuously (assuming
2581 non-stop mode). In addition, the "observer" variable is available
2582 to switch all of the different controls; in observer mode, GDB
2583 cannot affect the target's behavior at all, which is useful for
2584 tasks like diagnosing live systems in the field.
2586 * The new convenience variable $_thread holds the number of the
2589 * New remote packets
2593 Return the address of the Windows Thread Information Block of a given thread.
2597 In response to several of the tracepoint packets, the target may now
2598 also respond with a number of intermediate `qRelocInsn' request
2599 packets before the final result packet, to have GDB handle
2600 relocating an instruction to execute at a different address. This
2601 is particularly useful for stubs that support fast tracepoints. GDB
2602 reports support for this feature in the qSupported packet.
2606 List static tracepoint markers in the target program.
2610 List static tracepoint markers at a given address in the target
2613 qXfer:statictrace:read
2615 Read the static trace data collected (by a `collect $_sdata'
2616 tracepoint action). The remote stub reports support for this packet
2617 to gdb's qSupported query.
2621 Send the current settings of GDB's permission flags.
2625 Send part of the source (textual) form of a tracepoint definition,
2626 which includes location, conditional, and action list.
2628 * The source command now accepts a -s option to force searching for the
2629 script in the source search path even if the script name specifies
2632 * New features in the GDB remote stub, GDBserver
2634 - GDBserver now support tracepoints (including fast tracepoints, and
2635 static tracepoints). The feature is currently supported by the
2636 i386-linux and amd64-linux builds. See the "Tracepoints support
2637 in gdbserver" section in the manual for more information.
2639 GDBserver JIT compiles the tracepoint's conditional agent
2640 expression bytecode into native code whenever possible for low
2641 overhead dynamic tracepoints conditionals. For such tracepoints,
2642 an expression that examines program state is evaluated when the
2643 tracepoint is reached, in order to determine whether to capture
2644 trace data. If the condition is simple and false, processing the
2645 tracepoint finishes very quickly and no data is gathered.
2647 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2648 for static tracepoints support.
2650 - GDBserver now supports x86_64 Windows 64-bit debugging.
2652 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2653 it understands register description.
2655 * The --batch flag now disables pagination and queries.
2657 * X86 general purpose registers
2659 GDB now supports reading/writing byte, word and double-word x86
2660 general purpose registers directly. This means you can use, say,
2661 $ah or $ax to refer, respectively, to the byte register AH and
2662 16-bit word register AX that are actually portions of the 32-bit
2663 register EAX or 64-bit register RAX.
2665 * The `commands' command now accepts a range of breakpoints to modify.
2666 A plain `commands' following a command that creates multiple
2667 breakpoints affects all the breakpoints set by that command. This
2668 applies to breakpoints set by `rbreak', and also applies when a
2669 single `break' command creates multiple breakpoints (e.g.,
2670 breakpoints on overloaded c++ functions).
2672 * The `rbreak' command now accepts a filename specification as part of
2673 its argument, limiting the functions selected by the regex to those
2674 in the specified file.
2676 * Support for remote debugging Windows and SymbianOS shared libraries
2677 from Unix hosts has been improved. Non Windows GDB builds now can
2678 understand target reported file names that follow MS-DOS based file
2679 system semantics, such as file names that include drive letters and
2680 use the backslash character as directory separator. This makes it
2681 possible to transparently use the "set sysroot" and "set
2682 solib-search-path" on Unix hosts to point as host copies of the
2683 target's shared libraries. See the new command "set
2684 target-file-system-kind" described below, and the "Commands to
2685 specify files" section in the user manual for more information.
2689 eval template, expressions...
2690 Convert the values of one or more expressions under the control
2691 of the string template to a command line, and call it.
2693 set target-file-system-kind unix|dos-based|auto
2694 show target-file-system-kind
2695 Set or show the assumed file system kind for target reported file
2698 save breakpoints <filename>
2699 Save all current breakpoint definitions to a file suitable for use
2700 in a later debugging session. To read the saved breakpoint
2701 definitions, use the `source' command.
2703 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2706 info static-tracepoint-markers
2707 Display information about static tracepoint markers in the target.
2709 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2710 Define a static tracepoint by probing a marker at the given
2711 function, line, address, or marker ID.
2715 Enable and disable observer mode.
2717 set may-write-registers on|off
2718 set may-write-memory on|off
2719 set may-insert-breakpoints on|off
2720 set may-insert-tracepoints on|off
2721 set may-insert-fast-tracepoints on|off
2722 set may-interrupt on|off
2723 Set individual permissions for GDB effects on the target. Note that
2724 some of these settings can have undesirable or surprising
2725 consequences, particularly when changed in the middle of a session.
2726 For instance, disabling the writing of memory can prevent
2727 breakpoints from being inserted, cause single-stepping to fail, or
2728 even crash your program, if you disable after breakpoints have been
2729 inserted. However, GDB should not crash.
2731 set record memory-query on|off
2732 show record memory-query
2733 Control whether to stop the inferior if memory changes caused
2734 by an instruction cannot be recorded.
2739 The disassemble command now supports "start,+length" form of two arguments.
2743 ** GDB now provides a new directory location, called the python directory,
2744 where Python scripts written for GDB can be installed. The location
2745 of that directory is <data-directory>/python, where <data-directory>
2746 is the GDB data directory. For more details, see section `Scripting
2747 GDB using Python' in the manual.
2749 ** The GDB Python API now has access to breakpoints, symbols, symbol
2750 tables, program spaces, inferiors, threads and frame's code blocks.
2751 Additionally, GDB Parameters can now be created from the API, and
2752 manipulated via set/show in the CLI.
2754 ** New functions gdb.target_charset, gdb.target_wide_charset,
2755 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2757 ** New exception gdb.GdbError.
2759 ** Pretty-printers are now also looked up in the current program space.
2761 ** Pretty-printers can now be individually enabled and disabled.
2763 ** GDB now looks for names of Python scripts to auto-load in a
2764 special section named `.debug_gdb_scripts', in addition to looking
2765 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2767 * Tracepoint actions were unified with breakpoint commands. In particular,
2768 there are no longer differences in "info break" output for breakpoints and
2769 tracepoints and the "commands" command can be used for both tracepoints and
2770 regular breakpoints.
2774 ARM Symbian arm*-*-symbianelf*
2776 * D language support.
2777 GDB now supports debugging programs written in the D programming
2780 * GDB now supports the extended ptrace interface for PowerPC which is
2781 available since Linux kernel version 2.6.34. This automatically enables
2782 any hardware breakpoints and additional hardware watchpoints available in
2783 the processor. The old ptrace interface exposes just one hardware
2784 watchpoint and no hardware breakpoints.
2786 * GDB is now able to use the Data Value Compare (DVC) register available on
2787 embedded PowerPC processors to implement in hardware simple watchpoint
2788 conditions of the form:
2790 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2792 This works in native GDB running on Linux kernels with the extended ptrace
2793 interface mentioned above.
2795 *** Changes in GDB 7.1
2799 ** Namespace Support
2801 GDB now supports importing of namespaces in C++. This enables the
2802 user to inspect variables from imported namespaces. Support for
2803 namepace aliasing has also been added. So, if a namespace is
2804 aliased in the current scope (e.g. namepace C=A; ) the user can
2805 print variables using the alias (e.g. (gdb) print C::x).
2809 All known bugs relating to the printing of virtual base class were
2810 fixed. It is now possible to call overloaded static methods using a
2815 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2816 and reinterpret_cast<> are now handled by the C++ expression parser.
2820 Xilinx MicroBlaze microblaze-*-*
2825 Xilinx MicroBlaze microblaze
2828 * Multi-program debugging.
2830 GDB now has support for multi-program (a.k.a. multi-executable or
2831 multi-exec) debugging. This allows for debugging multiple inferiors
2832 simultaneously each running a different program under the same GDB
2833 session. See "Debugging Multiple Inferiors and Programs" in the
2834 manual for more information. This implied some user visible changes
2835 in the multi-inferior support. For example, "info inferiors" now
2836 lists inferiors that are not running yet or that have exited
2837 already. See also "New commands" and "New options" below.
2839 * New tracing features
2841 GDB's tracepoint facility now includes several new features:
2843 ** Trace state variables
2845 GDB tracepoints now include support for trace state variables, which
2846 are variables managed by the target agent during a tracing
2847 experiment. They are useful for tracepoints that trigger each
2848 other, so for instance one tracepoint can count hits in a variable,
2849 and then a second tracepoint has a condition that is true when the
2850 count reaches a particular value. Trace state variables share the
2851 $-syntax of GDB convenience variables, and can appear in both
2852 tracepoint actions and condition expressions. Use the "tvariable"
2853 command to create, and "info tvariables" to view; see "Trace State
2854 Variables" in the manual for more detail.
2858 GDB now includes an option for defining fast tracepoints, which
2859 targets may implement more efficiently, such as by installing a jump
2860 into the target agent rather than a trap instruction. The resulting
2861 speedup can be by two orders of magnitude or more, although the
2862 tradeoff is that some program locations on some target architectures
2863 might not allow fast tracepoint installation, for instance if the
2864 instruction to be replaced is shorter than the jump. To request a
2865 fast tracepoint, use the "ftrace" command, with syntax identical to
2866 the regular trace command.
2868 ** Disconnected tracing
2870 It is now possible to detach GDB from the target while it is running
2871 a trace experiment, then reconnect later to see how the experiment
2872 is going. In addition, a new variable disconnected-tracing lets you
2873 tell the target agent whether to continue running a trace if the
2874 connection is lost unexpectedly.
2878 GDB now has the ability to save the trace buffer into a file, and
2879 then use that file as a target, similarly to you can do with
2880 corefiles. You can select trace frames, print data that was
2881 collected in them, and use tstatus to display the state of the
2882 tracing run at the moment that it was saved. To create a trace
2883 file, use "tsave <filename>", and to use it, do "target tfile
2886 ** Circular trace buffer
2888 You can ask the target agent to handle the trace buffer as a
2889 circular buffer, discarding the oldest trace frames to make room for
2890 newer ones, by setting circular-trace-buffer to on. This feature may
2891 not be available for all target agents.
2896 The disassemble command, when invoked with two arguments, now requires
2897 the arguments to be comma-separated.
2900 The info variables command now displays variable definitions. Files
2901 which only declare a variable are not shown.
2904 The source command is now capable of sourcing Python scripts.
2905 This feature is dependent on the debugger being build with Python
2908 Related to this enhancement is also the introduction of a new command
2909 "set script-extension" (see below).
2911 * New commands (for set/show, see "New options" below)
2913 record save [<FILENAME>]
2914 Save a file (in core file format) containing the process record
2915 execution log for replay debugging at a later time.
2917 record restore <FILENAME>
2918 Restore the process record execution log that was saved at an
2919 earlier time, for replay debugging.
2921 add-inferior [-copies <N>] [-exec <FILENAME>]
2924 clone-inferior [-copies <N>] [ID]
2925 Make a new inferior ready to execute the same program another
2926 inferior has loaded.
2931 maint info program-spaces
2932 List the program spaces loaded into GDB.
2934 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2935 show remote interrupt-sequence
2936 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2937 as the sequence to the remote target in order to interrupt the execution.
2938 Ctrl-C is a default. Some system prefers BREAK which is high level of
2939 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2940 Magic SysRq g. It is BREAK signal and character 'g'.
2942 set remote interrupt-on-connect [on | off]
2943 show remote interrupt-on-connect
2944 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2945 remote target when gdb connects to it. This is needed when you debug
2948 set remotebreak [on | off]
2950 Deprecated. Use "set/show remote interrupt-sequence" instead.
2952 tvariable $NAME [ = EXP ]
2953 Create or modify a trace state variable.
2956 List trace state variables and their values.
2958 delete tvariable $NAME ...
2959 Delete one or more trace state variables.
2962 Evaluate the given expressions without collecting anything into the
2963 trace buffer. (Valid in tracepoint actions only.)
2965 ftrace FN / FILE:LINE / *ADDR
2966 Define a fast tracepoint at the given function, line, or address.
2968 * New expression syntax
2970 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2971 GDB now parses 0b101010 identically with 42.
2975 set follow-exec-mode new|same
2976 show follow-exec-mode
2977 Control whether GDB reuses the same inferior across an exec call or
2978 creates a new one. This is useful to be able to restart the old
2979 executable after the inferior having done an exec call.
2981 set default-collect EXPR, ...
2982 show default-collect
2983 Define a list of expressions to be collected at each tracepoint.
2984 This is a useful way to ensure essential items are not overlooked,
2985 such as registers or a critical global variable.
2987 set disconnected-tracing
2988 show disconnected-tracing
2989 If set to 1, the target is instructed to continue tracing if it
2990 loses its connection to GDB. If 0, the target is to stop tracing
2993 set circular-trace-buffer
2994 show circular-trace-buffer
2995 If set to on, the target is instructed to use a circular trace buffer
2996 and discard the oldest trace frames instead of stopping the trace due
2997 to a full trace buffer. If set to off, the trace stops when the buffer
2998 fills up. Some targets may not support this.
3000 set script-extension off|soft|strict
3001 show script-extension
3002 If set to "off", the debugger does not perform any script language
3003 recognition, and all sourced files are assumed to be GDB scripts.
3004 If set to "soft" (the default), files are sourced according to
3005 filename extension, falling back to GDB scripts if the first
3007 If set to "strict", files are sourced according to filename extension.
3009 set ada trust-PAD-over-XVS on|off
3010 show ada trust-PAD-over-XVS
3011 If off, activate a workaround against a bug in the debugging information
3012 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
3013 the GCC sources for more information about the GNAT encoding and
3014 PAD types in particular). It is always safe to set this option to
3015 off, but this introduces a slight performance penalty. The default
3018 * Python API Improvements
3020 ** GDB provides the new class gdb.LazyString. This is useful in
3021 some pretty-printing cases. The new method gdb.Value.lazy_string
3022 provides a simple way to create objects of this type.
3024 ** The fields returned by gdb.Type.fields now have an
3025 `is_base_class' attribute.
3027 ** The new method gdb.Type.range returns the range of an array type.
3029 ** The new method gdb.parse_and_eval can be used to parse and
3030 evaluate an expression.
3032 * New remote packets
3035 Define a trace state variable.
3038 Get the current value of a trace state variable.
3041 Set desired tracing behavior upon disconnection.
3044 Set the trace buffer to be linear or circular.
3047 Get data about the tracepoints currently in use.
3051 Process record now works correctly with hardware watchpoints.
3053 Multiple bug fixes have been made to the mips-irix port, making it
3054 much more reliable. In particular:
3055 - Debugging threaded applications is now possible again. Previously,
3056 GDB would hang while starting the program, or while waiting for
3057 the program to stop at a breakpoint.
3058 - Attaching to a running process no longer hangs.
3059 - An error occurring while loading a core file has been fixed.
3060 - Changing the value of the PC register now works again. This fixes
3061 problems observed when using the "jump" command, or when calling
3062 a function from GDB, or even when assigning a new value to $pc.
3063 - With the "finish" and "return" commands, the return value for functions
3064 returning a small array is now correctly printed.
3065 - It is now possible to break on shared library code which gets executed
3066 during a shared library init phase (code executed while executing
3067 their .init section). Previously, the breakpoint would have no effect.
3068 - GDB is now able to backtrace through the signal handler for
3069 non-threaded programs.
3071 PIE (Position Independent Executable) programs debugging is now supported.
3072 This includes debugging execution of PIC (Position Independent Code) shared
3073 libraries although for that, it should be possible to run such libraries as an
3076 *** Changes in GDB 7.0
3078 * GDB now has an interface for JIT compilation. Applications that
3079 dynamically generate code can create symbol files in memory and register
3080 them with GDB. For users, the feature should work transparently, and
3081 for JIT developers, the interface is documented in the GDB manual in the
3082 "JIT Compilation Interface" chapter.
3084 * Tracepoints may now be conditional. The syntax is as for
3085 breakpoints; either an "if" clause appended to the "trace" command,
3086 or the "condition" command is available. GDB sends the condition to
3087 the target for evaluation using the same bytecode format as is used
3088 for tracepoint actions.
3090 * The disassemble command now supports: an optional /r modifier, print the
3091 raw instructions in hex as well as in symbolic form, and an optional /m
3092 modifier to print mixed source+assembly.
3094 * Process record and replay
3096 In a architecture environment that supports ``process record and
3097 replay'', ``process record and replay'' target can record a log of
3098 the process execution, and replay it with both forward and reverse
3101 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3102 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3103 set execution-direction {forward|reverse}, for targets that support
3106 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3107 feature is available with a native GDB running on kernel version
3110 * GDB now has support for multi-byte and wide character sets on the
3111 target. Strings whose character type is wchar_t, char16_t, or
3112 char32_t are now correctly printed. GDB supports wide- and unicode-
3113 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3114 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3115 `printf'. This feature requires iconv to work properly; if your
3116 system does not have a working iconv, GDB can use GNU libiconv. See
3117 the installation instructions for more information.
3119 * GDB now supports automatic retrieval of shared library files from
3120 remote targets. To use this feature, specify a system root that begins
3121 with the `remote:' prefix, either via the `set sysroot' command or via
3122 the `--with-sysroot' configure-time option.
3124 * "info sharedlibrary" now takes an optional regex of libraries to show,
3125 and it now reports if a shared library has no debugging information.
3127 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3128 now complete on file names.
3130 * When completing in expressions, gdb will attempt to limit
3131 completions to allowable structure or union fields, where appropriate.
3132 For instance, consider:
3134 # struct example { int f1; double f2; };
3135 # struct example variable;
3138 If the user types TAB at the end of this command line, the available
3139 completions will be "f1" and "f2".
3141 * Inlined functions are now supported. They show up in backtraces, and
3142 the "step", "next", and "finish" commands handle them automatically.
3144 * GDB now supports the token-splicing (##) and stringification (#)
3145 operators when expanding macros. It also supports variable-arity
3148 * GDB now supports inspecting extra signal information, exported by
3149 the new $_siginfo convenience variable. The feature is currently
3150 implemented on linux ARM, i386 and amd64.
3152 * GDB can now display the VFP floating point registers and NEON vector
3153 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3154 can provide these registers (requires Linux 2.6.30 or later). Remote
3155 and simulator targets may also provide them.
3157 * New remote packets
3160 Search memory for a sequence of bytes.
3163 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3164 operation over reliable transport links. Use of this packet is
3165 controlled by the `set remote noack-packet' command.
3168 Kill the process with the specified process ID. Use this in preference
3169 to `k' when multiprocess protocol extensions are supported.
3172 Obtains additional operating system information
3176 Read or write additional signal information.
3178 * Removed remote protocol undocumented extension
3180 An undocumented extension to the remote protocol's `S' stop reply
3181 packet that permited the stub to pass a process id was removed.
3182 Remote servers should use the `T' stop reply packet instead.
3184 * GDB now supports multiple function calling conventions according to the
3185 DWARF-2 DW_AT_calling_convention function attribute.
3187 * The SH target utilizes the aforementioned change to distinguish between gcc
3188 and Renesas calling convention. It also adds the new CLI commands
3189 `set/show sh calling-convention'.
3191 * GDB can now read compressed debug sections, as produced by GNU gold
3192 with the --compress-debug-sections=zlib flag.
3194 * 64-bit core files are now supported on AIX.
3196 * Thread switching is now supported on Tru64.
3198 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3199 which will be allocated using malloc later in program execution.
3201 * The qXfer:libraries:read remote procotol packet now allows passing a
3202 list of section offsets.
3204 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3205 conditions handling signals delivered during attach or thread creation
3206 have also been fixed.
3208 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3209 From the user's standpoint, all unqualified instances of True and False
3210 are treated as the standard definitions, regardless of context.
3212 * GDB now parses C++ symbol and type names more flexibly. For
3215 template<typename T> class C { };
3218 GDB will now correctly handle all of:
3220 ptype C<char const *>
3221 ptype C<char const*>
3222 ptype C<const char *>
3223 ptype C<const char*>
3225 * New features in the GDB remote stub, gdbserver
3227 - The "--wrapper" command-line argument tells gdbserver to use a
3228 wrapper program to launch programs for debugging.
3230 - On PowerPC and S/390 targets, it is now possible to use a single
3231 gdbserver executable to debug both 32-bit and 64-bit programs.
3232 (This requires gdbserver itself to be built as a 64-bit executable.)
3234 - gdbserver uses the new noack protocol mode for TCP connections to
3235 reduce communications latency, if also supported and enabled in GDB.
3237 - Support for the sparc64-linux-gnu target is now included in
3240 - The amd64-linux build of gdbserver now supports debugging both
3241 32-bit and 64-bit programs.
3243 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3244 now support hardware watchpoints, and will use them automatically
3249 GDB now has support for scripting using Python. Whether this is
3250 available is determined at configure time.
3252 New GDB commands can now be written in Python.
3254 * Ada tasking support
3256 Ada tasks can now be inspected in GDB. The following commands have
3260 Print the list of Ada tasks.
3262 Print detailed information about task number N.
3264 Print the task number of the current task.
3266 Switch the context of debugging to task number N.
3268 * Support for user-defined prefixed commands. The "define" command can
3269 add new commands to existing prefixes, e.g. "target".
3271 * Multi-inferior, multi-process debugging.
3273 GDB now has generalized support for multi-inferior debugging. See
3274 "Debugging Multiple Inferiors" in the manual for more information.
3275 Although availability still depends on target support, the command
3276 set is more uniform now. The GNU/Linux specific multi-forks support
3277 has been migrated to this new framework. This implied some user
3278 visible changes; see "New commands" and also "Removed commands"
3281 * Target descriptions can now describe the target OS ABI. See the
3282 "Target Description Format" section in the user manual for more
3285 * Target descriptions can now describe "compatible" architectures
3286 to indicate that the target can execute applications for a different
3287 architecture in addition to those for the main target architecture.
3288 See the "Target Description Format" section in the user manual for
3291 * Multi-architecture debugging.
3293 GDB now includes general supports for debugging applications on
3294 hybrid systems that use more than one single processor architecture
3295 at the same time. Each such hybrid architecture still requires
3296 specific support to be added. The only hybrid architecture supported
3297 in this version of GDB is the Cell Broadband Engine.
3299 * GDB now supports integrated debugging of Cell/B.E. applications that
3300 use both the PPU and SPU architectures. To enable support for hybrid
3301 Cell/B.E. debugging, you need to configure GDB to support both the
3302 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3303 --enable-targets configure option.
3305 * Non-stop mode debugging.
3307 For some targets, GDB now supports an optional mode of operation in
3308 which you can examine stopped threads while other threads continue
3309 to execute freely. This is referred to as non-stop mode, with the
3310 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3311 section in the user manual for more information.
3313 To be able to support remote non-stop debugging, a remote stub needs
3314 to implement the non-stop mode remote protocol extensions, as
3315 described in the "Remote Non-Stop" section of the user manual. The
3316 GDB remote stub, gdbserver, has been adjusted to support these
3317 extensions on linux targets.
3319 * New commands (for set/show, see "New options" below)
3321 catch syscall [NAME(S) | NUMBER(S)]
3322 Catch system calls. Arguments, which should be names of system
3323 calls or their numbers, mean catch only those syscalls. Without
3324 arguments, every syscall will be caught. When the inferior issues
3325 any of the specified syscalls, GDB will stop and announce the system
3326 call, both when it is called and when its call returns. This
3327 feature is currently available with a native GDB running on the
3328 Linux Kernel, under the following architectures: x86, x86_64,
3329 PowerPC and PowerPC64.
3331 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3333 Search memory for a sequence of bytes.
3335 maint set python print-stack
3336 maint show python print-stack
3337 Show a stack trace when an error is encountered in a Python script.
3340 Invoke CODE by passing it to the Python interpreter.
3345 These allow macros to be defined, undefined, and listed
3349 Show operating system information about processes.
3352 List the inferiors currently under GDB's control.
3355 Switch focus to inferior number NUM.
3358 Detach from inferior number NUM.
3361 Kill inferior number NUM.
3365 set spu stop-on-load
3366 show spu stop-on-load
3367 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3369 set spu auto-flush-cache
3370 show spu auto-flush-cache
3371 Control whether to automatically flush the software-managed cache
3372 during Cell/B.E. debugging.
3374 set sh calling-convention
3375 show sh calling-convention
3376 Control the calling convention used when calling SH target functions.
3379 show debug timestamp
3380 Control display of timestamps with GDB debugging output.
3382 set disassemble-next-line
3383 show disassemble-next-line
3384 Control display of disassembled source lines or instructions when
3387 set remote noack-packet
3388 show remote noack-packet
3389 Set/show the use of remote protocol QStartNoAckMode packet. See above
3390 under "New remote packets."
3392 set remote query-attached-packet
3393 show remote query-attached-packet
3394 Control use of remote protocol `qAttached' (query-attached) packet.
3396 set remote read-siginfo-object
3397 show remote read-siginfo-object
3398 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3401 set remote write-siginfo-object
3402 show remote write-siginfo-object
3403 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3406 set remote reverse-continue
3407 show remote reverse-continue
3408 Control use of remote protocol 'bc' (reverse-continue) packet.
3410 set remote reverse-step
3411 show remote reverse-step
3412 Control use of remote protocol 'bs' (reverse-step) packet.
3414 set displaced-stepping
3415 show displaced-stepping
3416 Control displaced stepping mode. Displaced stepping is a way to
3417 single-step over breakpoints without removing them from the debuggee.
3418 Also known as "out-of-line single-stepping".
3421 show debug displaced
3422 Control display of debugging info for displaced stepping.
3424 maint set internal-error
3425 maint show internal-error
3426 Control what GDB does when an internal error is detected.
3428 maint set internal-warning
3429 maint show internal-warning
3430 Control what GDB does when an internal warning is detected.
3435 Use a wrapper program to launch programs for debugging.
3437 set multiple-symbols (all|ask|cancel)
3438 show multiple-symbols
3439 The value of this variable can be changed to adjust the debugger behavior
3440 when an expression or a breakpoint location contains an ambiguous symbol
3441 name (an overloaded function name, for instance).
3443 set breakpoint always-inserted
3444 show breakpoint always-inserted
3445 Keep breakpoints always inserted in the target, as opposed to inserting
3446 them when resuming the target, and removing them when the target stops.
3447 This option can improve debugger performance on slow remote targets.
3449 set arm fallback-mode (arm|thumb|auto)
3450 show arm fallback-mode
3451 set arm force-mode (arm|thumb|auto)
3453 These commands control how ARM GDB determines whether instructions
3454 are ARM or Thumb. The default for both settings is auto, which uses
3455 the current CPSR value for instructions without symbols; previous
3456 versions of GDB behaved as if "set arm fallback-mode arm".
3458 set disable-randomization
3459 show disable-randomization
3460 Standalone programs run with the virtual address space randomization enabled
3461 by default on some platforms. This option keeps the addresses stable across
3462 multiple debugging sessions.
3466 Control whether other threads are stopped or not when some thread hits
3471 Requests that asynchronous execution is enabled in the target, if available.
3472 In this case, it's possible to resume target in the background, and interact
3473 with GDB while the target is running. "show target-async" displays the
3474 current state of asynchronous execution of the target.
3476 set target-wide-charset
3477 show target-wide-charset
3478 The target-wide-charset is the name of the character set that GDB
3479 uses when printing characters whose type is wchar_t.
3481 set tcp auto-retry (on|off)
3483 set tcp connect-timeout
3484 show tcp connect-timeout
3485 These commands allow GDB to retry failed TCP connections to a remote stub
3486 with a specified timeout period; this is useful if the stub is launched
3487 in parallel with GDB but may not be ready to accept connections immediately.
3489 set libthread-db-search-path
3490 show libthread-db-search-path
3491 Control list of directories which GDB will search for appropriate
3494 set schedule-multiple (on|off)
3495 show schedule-multiple
3496 Allow GDB to resume all threads of all processes or only threads of
3497 the current process.
3501 Use more aggressive caching for accesses to the stack. This improves
3502 performance of remote debugging (particularly backtraces) without
3503 affecting correctness.
3505 set interactive-mode (on|off|auto)
3506 show interactive-mode
3507 Control whether GDB runs in interactive mode (on) or not (off).
3508 When in interactive mode, GDB waits for the user to answer all
3509 queries. Otherwise, GDB does not wait and assumes the default
3510 answer. When set to auto (the default), GDB determines which
3511 mode to use based on the stdin settings.
3516 For program forks, this is replaced by the new more generic `info
3517 inferiors' command. To list checkpoints, you can still use the
3518 `info checkpoints' command, which was an alias for the `info forks'
3522 Replaced by the new `inferior' command. To switch between
3523 checkpoints, you can still use the `restart' command, which was an
3524 alias for the `fork' command.
3527 This is removed, since some targets don't have a notion of
3528 processes. To switch between processes, you can still use the
3529 `inferior' command using GDB's own inferior number.
3532 For program forks, this is replaced by the new more generic `kill
3533 inferior' command. To delete a checkpoint, you can still use the
3534 `delete checkpoint' command, which was an alias for the `delete
3538 For program forks, this is replaced by the new more generic `detach
3539 inferior' command. To detach a checkpoint, you can still use the
3540 `detach checkpoint' command, which was an alias for the `detach
3543 * New native configurations
3545 x86/x86_64 Darwin i[34567]86-*-darwin*
3547 x86_64 MinGW x86_64-*-mingw*
3551 Lattice Mico32 lm32-*
3552 x86 DICOS i[34567]86-*-dicos*
3553 x86_64 DICOS x86_64-*-dicos*
3556 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3557 (mingw32ce) debugging.
3563 These commands were actually not implemented on any target.
3565 *** Changes in GDB 6.8
3567 * New native configurations
3569 NetBSD/hppa hppa*-*netbsd*
3570 Xtensa GNU/Linux xtensa*-*-linux*
3574 NetBSD/hppa hppa*-*-netbsd*
3575 Xtensa GNU/Lunux xtensa*-*-linux*
3577 * Change in command line behavior -- corefiles vs. process ids.
3579 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3580 attaching to process NUMBER fails, GDB no longer attempts to open a
3581 core file named NUMBER. Attaching to a program using the -c option
3582 is no longer supported. Instead, use the '-p' or '--pid' options.
3584 * GDB can now be built as a native debugger for debugging Windows x86
3585 (mingw32) Portable Executable (PE) programs.
3587 * Pending breakpoints no longer change their number when their address
3590 * GDB now supports breakpoints with multiple locations,
3591 including breakpoints on C++ constructors, inside C++ templates,
3592 and in inlined functions.
3594 * GDB's ability to debug optimized code has been improved. GDB more
3595 accurately identifies function bodies and lexical blocks that occupy
3596 more than one contiguous range of addresses.
3598 * Target descriptions can now describe registers for PowerPC.
3600 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3601 registers on PowerPC targets.
3603 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3604 targets even when the libthread_db library is not available.
3606 * The GDB remote stub, gdbserver, now supports the new file transfer
3607 commands (remote put, remote get, and remote delete).
3609 * The GDB remote stub, gdbserver, now supports run and attach in
3610 extended-remote mode.
3612 * hppa*64*-*-hpux11* target broken
3613 The debugger is unable to start a program and fails with the following
3614 error: "Error trying to get information about dynamic linker".
3615 The gdb-6.7 release is also affected.
3617 * GDB now supports the --enable-targets= configure option to allow
3618 building a single GDB executable that supports multiple remote
3619 target architectures.
3621 * GDB now supports debugging C and C++ programs which use the
3622 Decimal Floating Point extension. In addition, the PowerPC target
3623 now has a set of pseudo-registers to inspect decimal float values
3624 stored in two consecutive float registers.
3626 * The -break-insert MI command can optionally create pending
3629 * Improved support for debugging Ada
3630 Many improvements to the Ada language support have been made. These
3632 - Better support for Ada2005 interface types
3633 - Improved handling of arrays and slices in general
3634 - Better support for Taft-amendment types
3635 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3637 - Improved command completion in Ada
3640 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3645 set print frame-arguments (all|scalars|none)
3646 show print frame-arguments
3647 The value of this variable can be changed to control which argument
3648 values should be printed by the debugger when displaying a frame.
3653 Transfer files to and from a remote target, and delete remote files.
3660 Transfer files to and from a remote target, and delete remote files.
3662 * New remote packets
3669 Open, close, read, write, and delete files on the remote system.
3672 Attach to an existing process on the remote system, in extended-remote
3676 Run a new process on the remote system, in extended-remote mode.
3678 *** Changes in GDB 6.7
3680 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3681 bfd, libiberty and opcodes, as revealed by static analysis donated by
3682 Coverity, Inc. (http://scan.coverity.com).
3684 * When looking up multiply-defined global symbols, GDB will now prefer the
3685 symbol definition in the current shared library if it was built using the
3686 -Bsymbolic linker option.
3688 * When the Text User Interface (TUI) is not configured, GDB will now
3689 recognize the -tui command-line option and print a message that the TUI
3692 * The GDB remote stub, gdbserver, now has lower overhead for high
3693 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3695 * GDB for MIPS targets now autodetects whether a remote target provides
3696 32-bit or 64-bit register values.
3698 * Support for C++ member pointers has been improved.
3700 * GDB now understands XML target descriptions, which specify the
3701 target's overall architecture. GDB can read a description from
3702 a local file or over the remote serial protocol.
3704 * Vectors of single-byte data use a new integer type which is not
3705 automatically displayed as character or string data.
3707 * The /s format now works with the print command. It displays
3708 arrays of single-byte integers and pointers to single-byte integers
3711 * Target descriptions can now describe target-specific registers,
3712 for architectures which have implemented the support (currently
3713 only ARM, M68K, and MIPS).
3715 * GDB and the GDB remote stub, gdbserver, now support the XScale
3718 * The GDB remote stub, gdbserver, has been updated to support
3719 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3720 has been rewritten to use the standard GDB remote protocol.
3722 * GDB can now step into C++ functions which are called through thunks.
3724 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3726 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3727 layout. It also supports a TextSeg= and DataSeg= response when only
3728 segment base addresses (rather than offsets) are available.
3730 * The /i format now outputs any trailing branch delay slot instructions
3731 immediately following the last instruction within the count specified.
3733 * The GDB remote protocol "T" stop reply packet now supports a
3734 "library" response. Combined with the new "qXfer:libraries:read"
3735 packet, this response allows GDB to debug shared libraries on targets
3736 where the operating system manages the list of loaded libraries (e.g.
3737 Windows and SymbianOS).
3739 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3740 (DLLs) on Windows and Windows CE targets.
3742 * GDB now supports a faster verification that a .debug file matches its binary
3743 according to its build-id signature, if the signature is present.
3749 Enable or disable hardware flow control (RTS/CTS) on the serial port
3750 when debugging using remote targets.
3752 set mem inaccessible-by-default
3753 show mem inaccessible-by-default
3754 If the target supplies a memory map, for instance via the remote
3755 protocol's "qXfer:memory-map:read" packet, setting this variable
3756 prevents GDB from accessing memory outside the memory map. This
3757 is useful for targets with memory mapped registers or which react
3758 badly to accesses of unmapped address space.
3760 set breakpoint auto-hw
3761 show breakpoint auto-hw
3762 If the target supplies a memory map, for instance via the remote
3763 protocol's "qXfer:memory-map:read" packet, setting this variable
3764 lets GDB use hardware breakpoints automatically for memory regions
3765 where it can not use software breakpoints. This covers both the
3766 "break" command and internal breakpoints used for other commands
3767 including "next" and "finish".
3770 catch exception unhandled
3771 Stop the program execution when Ada exceptions are raised.
3774 Stop the program execution when an Ada assertion failed.
3778 Set an alternate system root for target files. This is a more
3779 general version of "set solib-absolute-prefix", which is now
3780 an alias to "set sysroot".
3783 Provide extended SPU facility status information. This set of
3784 commands is available only when debugging the Cell/B.E. SPU
3787 * New native configurations
3789 OpenBSD/sh sh*-*openbsd*
3792 unset tdesc filename
3794 Use the specified local file as an XML target description, and do
3795 not query the target for its built-in description.
3799 OpenBSD/sh sh*-*-openbsd*
3800 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3801 Toshiba Media Processor mep-elf
3803 * New remote packets
3806 Ignore the specified signals; pass them directly to the debugged program
3807 without stopping other threads or reporting them to GDB.
3809 qXfer:features:read:
3810 Read an XML target description from the target, which describes its
3815 Read or write contents of an spufs file on the target system. These
3816 packets are available only on the Cell/B.E. SPU architecture.
3818 qXfer:libraries:read:
3819 Report the loaded shared libraries. Combined with new "T" packet
3820 response, this packet allows GDB to debug shared libraries on
3821 targets where the operating system manages the list of loaded
3822 libraries (e.g. Windows and SymbianOS).
3826 Support for these obsolete configurations has been removed.
3834 i[34567]86-*-lynxos*
3835 i[34567]86-*-netware*
3836 i[34567]86-*-sco3.2v5*
3837 i[34567]86-*-sco3.2v4*
3839 i[34567]86-*-sysv4.2*
3842 i[34567]86-*-unixware2*
3843 i[34567]86-*-unixware*
3852 * Other removed features
3859 Various m68k-only ROM monitors.
3866 Various Renesas ROM monitors and debugging interfaces for SH and
3871 Support for a Macraigor serial interface to on-chip debugging.
3872 GDB does not directly support the newer parallel or USB
3877 A debug information format. The predecessor to DWARF 2 and
3878 DWARF 3, which are still supported.
3880 Support for the HP aCC compiler on HP-UX/PA-RISC
3882 SOM-encapsulated symbolic debugging information, automatic
3883 invocation of pxdb, and the aCC custom C++ ABI. This does not
3884 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3885 with aCC can still be debugged on an assembly level.
3887 MIPS ".pdr" sections
3889 A MIPS-specific format used to describe stack frame layout
3890 in debugging information.
3894 GDB could work with an older version of Guile to debug
3895 the interpreter and Scheme programs running in it.
3897 set mips stack-arg-size
3898 set mips saved-gpreg-size
3900 Use "set mips abi" to control parameter passing for MIPS.
3902 *** Changes in GDB 6.6
3907 Cell Broadband Engine SPU spu-elf
3909 * GDB can now be configured as a cross-debugger targeting native Windows
3910 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3911 running on a Windows system over TCP/IP to debug Windows programs.
3913 * The GDB remote stub, gdbserver, has been updated to support Windows and
3914 Cygwin debugging. Both single-threaded and multi-threaded programs are
3917 * The "set trust-readonly-sections" command works again. This command was
3918 broken in GDB 6.3, 6.4, and 6.5.
3920 * The "load" command now supports writing to flash memory, if the remote
3921 stub provides the required support.
3923 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3924 longer requires symbolic debug information (e.g. DWARF-2).
3929 unset substitute-path
3930 show substitute-path
3931 Manage a list of substitution rules that GDB uses to rewrite the name
3932 of the directories where the sources are located. This can be useful
3933 for instance when the sources were moved to a different location
3934 between compilation and debugging.
3938 Print each CLI command as it is executed. Each command is prefixed with
3939 a number of `+' symbols representing the nesting depth.
3940 The source command now has a `-v' option to enable the same feature.
3944 The ARM Demon monitor support (RDP protocol, "target rdp").
3946 Kernel Object Display, an embedded debugging feature which only worked with
3947 an obsolete version of Cisco IOS.
3949 The 'set download-write-size' and 'show download-write-size' commands.
3951 * New remote packets
3954 Tell a stub about GDB client features, and request remote target features.
3955 The first feature implemented is PacketSize, which allows the target to
3956 specify the size of packets it can handle - to minimize the number of
3957 packets required and improve performance when connected to a remote
3961 Fetch an OS auxilliary vector from the remote stub. This packet is a
3962 more efficient replacement for qPart:auxv:read.
3964 qXfer:memory-map:read:
3965 Fetch a memory map from the remote stub, including information about
3966 RAM, ROM, and flash memory devices.
3971 Erase and program a flash memory device.
3973 * Removed remote packets
3976 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3977 used it, and only gdbserver implemented it.
3979 *** Changes in GDB 6.5
3983 Renesas M32C/M16C m32c-elf
3985 Morpho Technologies ms1 ms1-elf
3989 init-if-undefined Initialize a convenience variable, but
3990 only if it doesn't already have a value.
3992 The following commands are presently only implemented for native GNU/Linux:
3994 checkpoint Save a snapshot of the program state.
3996 restart <n> Return the program state to a
3997 previously saved state.
3999 info checkpoints List currently saved checkpoints.
4001 delete-checkpoint <n> Delete a previously saved checkpoint.
4003 set|show detach-on-fork Tell gdb whether to detach from a newly
4004 forked process, or to keep debugging it.
4006 info forks List forks of the user program that
4007 are available to be debugged.
4009 fork <n> Switch to debugging one of several
4010 forks of the user program that are
4011 available to be debugged.
4013 delete-fork <n> Delete a fork from the list of forks
4014 that are available to be debugged (and
4015 kill the forked process).
4017 detach-fork <n> Delete a fork from the list of forks
4018 that are available to be debugged (and
4019 allow the process to continue).
4023 Morpho Technologies ms2 ms1-elf
4025 * Improved Windows host support
4027 GDB now builds as a cross debugger hosted on i686-mingw32, including
4028 native console support, and remote communications using either
4029 network sockets or serial ports.
4031 * Improved Modula-2 language support
4033 GDB can now print most types in the Modula-2 syntax. This includes:
4034 basic types, set types, record types, enumerated types, range types,
4035 pointer types and ARRAY types. Procedure var parameters are correctly
4036 printed and hexadecimal addresses and character constants are also
4037 written in the Modula-2 syntax. Best results can be obtained by using
4038 GNU Modula-2 together with the -gdwarf-2 command line option.
4042 The ARM rdi-share module.
4044 The Netware NLM debug server.
4046 *** Changes in GDB 6.4
4048 * New native configurations
4050 OpenBSD/arm arm*-*-openbsd*
4051 OpenBSD/mips64 mips64-*-openbsd*
4055 Morpho Technologies ms1 ms1-elf
4057 * New command line options
4059 --batch-silent As for --batch, but totally silent.
4060 --return-child-result The debugger will exist with the same value
4061 the child (debugged) program exited with.
4062 --eval-command COMMAND, -ex COMMAND
4063 Execute a single GDB CLI command. This may be
4064 specified multiple times and in conjunction
4065 with the --command (-x) option.
4067 * Deprecated commands removed
4069 The following commands, that were deprecated in 2000, have been
4073 set|show arm disassembly-flavor set|show arm disassembler
4074 othernames set arm disassembler
4075 set|show remotedebug set|show debug remote
4076 set|show archdebug set|show debug arch
4077 set|show eventdebug set|show debug event
4080 * New BSD user-level threads support
4082 It is now possible to debug programs using the user-level threads
4083 library on OpenBSD and FreeBSD. Currently supported (target)
4086 FreeBSD/amd64 x86_64-*-freebsd*
4087 FreeBSD/i386 i386-*-freebsd*
4088 OpenBSD/i386 i386-*-openbsd*
4090 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4091 are not yet supported.
4093 * New support for Matsushita MN10300 w/sim added
4094 (Work in progress). mn10300-elf.
4096 * REMOVED configurations and files
4098 VxWorks and the XDR protocol *-*-vxworks
4099 Motorola MCORE mcore-*-*
4100 National Semiconductor NS32000 ns32k-*-*
4102 * New "set print array-indexes" command
4104 After turning this setting "on", GDB prints the index of each element
4105 when displaying arrays. The default is "off" to preserve the previous
4108 * VAX floating point support
4110 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4112 * User-defined command support
4114 In addition to using $arg0..$arg9 for argument passing, it is now possible
4115 to use $argc to determine now many arguments have been passed. See the
4116 section on user-defined commands in the user manual for more information.
4118 *** Changes in GDB 6.3:
4120 * New command line option
4122 GDB now accepts -l followed by a number to set the timeout for remote
4125 * GDB works with GCC -feliminate-dwarf2-dups
4127 GDB now supports a more compact representation of DWARF-2 debug
4128 information using DW_FORM_ref_addr references. These are produced
4129 by GCC with the option -feliminate-dwarf2-dups and also by some
4130 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4131 to use -feliminate-dwarf2-dups.
4133 * Internationalization
4135 When supported by the host system, GDB will be built with
4136 internationalization (libintl). The task of marking up the sources is
4137 continued, we're looking forward to our first translation.
4141 Initial support for debugging programs compiled with the GNAT
4142 implementation of the Ada programming language has been integrated
4143 into GDB. In this release, support is limited to expression evaluation.
4145 * New native configurations
4147 GNU/Linux/m32r m32r-*-linux-gnu
4151 GDB's remote protocol now includes support for the 'p' packet. This
4152 packet is used to fetch individual registers from a remote inferior.
4154 * END-OF-LIFE registers[] compatibility module
4156 GDB's internal register infrastructure has been completely rewritten.
4157 The new infrastructure making possible the implementation of key new
4158 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4161 GDB 6.3 will be the last release to include the the registers[]
4162 compatibility module that allowed out-of-date configurations to
4163 continue to work. This change directly impacts the following
4173 powerpc bdm protocol
4175 Unless there is activity to revive these configurations, they will be
4176 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4178 * OBSOLETE configurations and files
4180 Configurations that have been declared obsolete in this release have
4181 been commented out. Unless there is activity to revive these
4182 configurations, the next release of GDB will have their sources
4183 permanently REMOVED.
4192 *** Changes in GDB 6.2.1:
4194 * MIPS `break main; run' gave an heuristic-fence-post warning
4196 When attempting to run even a simple program, a warning about
4197 heuristic-fence-post being hit would be reported. This problem has
4200 * MIPS IRIX 'long double' crashed GDB
4202 When examining a long double variable, GDB would get a segmentation
4203 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4204 IRIX long double values).
4208 A bug in the VAX stack code was causing problems with the "next"
4209 command. This problem has been fixed.
4211 *** Changes in GDB 6.2:
4213 * Fix for ``many threads''
4215 On GNU/Linux systems that use the NPTL threads library, a program
4216 rapidly creating and deleting threads would confuse GDB leading to the
4219 ptrace: No such process.
4220 thread_db_get_info: cannot get thread info: generic error
4222 This problem has been fixed.
4224 * "-async" and "-noasync" options removed.
4226 Support for the broken "-noasync" option has been removed (it caused
4229 * New ``start'' command.
4231 This command runs the program until the begining of the main procedure.
4233 * New BSD Kernel Data Access Library (libkvm) interface
4235 Using ``target kvm'' it is now possible to debug kernel core dumps and
4236 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4237 platforms. Currently supported (native-only) configurations are:
4239 FreeBSD/amd64 x86_64-*-freebsd*
4240 FreeBSD/i386 i?86-*-freebsd*
4241 NetBSD/i386 i?86-*-netbsd*
4242 NetBSD/m68k m68*-*-netbsd*
4243 NetBSD/sparc sparc-*-netbsd*
4244 OpenBSD/amd64 x86_64-*-openbsd*
4245 OpenBSD/i386 i?86-*-openbsd*
4246 OpenBSD/m68k m68*-openbsd*
4247 OpenBSD/sparc sparc-*-openbsd*
4249 * Signal trampoline code overhauled
4251 Many generic problems with GDB's signal handling code have been fixed.
4252 These include: backtraces through non-contiguous stacks; recognition
4253 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4254 call; backtrace through a signal trampoline; step into and out of
4255 signal handlers; and single-stepping in the signal trampoline.
4257 Please note that kernel bugs are a limiting factor here. These
4258 features have been shown to work on an s390 GNU/Linux system that
4259 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4261 * Cygwin support for DWARF 2 added.
4263 * New native configurations
4265 GNU/Linux/hppa hppa*-*-linux*
4266 OpenBSD/hppa hppa*-*-openbsd*
4267 OpenBSD/m68k m68*-*-openbsd*
4268 OpenBSD/m88k m88*-*-openbsd*
4269 OpenBSD/powerpc powerpc-*-openbsd*
4270 NetBSD/vax vax-*-netbsd*
4271 OpenBSD/vax vax-*-openbsd*
4273 * END-OF-LIFE frame compatibility module
4275 GDB's internal frame infrastructure has been completely rewritten.
4276 The new infrastructure making it possible to support key new features
4277 including DWARF 2 Call Frame Information. To aid in the task of
4278 migrating old configurations to this new infrastructure, a
4279 compatibility module, that allowed old configurations to continue to
4280 work, was also included.
4282 GDB 6.2 will be the last release to include this frame compatibility
4283 module. This change directly impacts the following configurations:
4293 Unless there is activity to revive these configurations, they will be
4294 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4296 * REMOVED configurations and files
4298 Sun 3, running SunOS 3 m68*-*-sunos3*
4299 Sun 3, running SunOS 4 m68*-*-sunos4*
4300 Sun 2, running SunOS 3 m68000-*-sunos3*
4301 Sun 2, running SunOS 4 m68000-*-sunos4*
4302 Motorola 680x0 running LynxOS m68*-*-lynxos*
4303 AT&T 3b1/Unix pc m68*-att-*
4304 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4305 decstation mips-dec-* mips-little-*
4306 riscos mips-*-riscos* mips-*-sysv*
4307 sonymips mips-sony-*
4308 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4310 *** Changes in GDB 6.1.1:
4312 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4314 The TUI (Text-mode User Interface) is now built as part of a default
4315 GDB configuration. It is enabled by either selecting the TUI with the
4316 command line option "-i=tui" or by running the separate "gdbtui"
4317 program. For more information on the TUI, see the manual "Debugging
4320 * Pending breakpoint support (also included in GDB 6.1)
4322 Support has been added to allow you to specify breakpoints in shared
4323 libraries that have not yet been loaded. If a breakpoint location
4324 cannot be found, and the "breakpoint pending" option is set to auto,
4325 GDB queries you if you wish to make the breakpoint pending on a future
4326 shared-library load. If and when GDB resolves the breakpoint symbol,
4327 the pending breakpoint is removed as one or more regular breakpoints
4330 Pending breakpoints are very useful for GCJ Java debugging.
4332 * Fixed ISO-C build problems
4334 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4335 non ISO-C code that stopped them being built using a more strict ISO-C
4336 compiler (e.g., IBM's C compiler).
4338 * Fixed build problem on IRIX 5
4340 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4341 wasn't able to compile compile on an IRIX 5 system.
4343 * Added execute permission to gdb/gdbserver/configure
4345 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4346 permission. This bug would cause configure to fail on a number of
4347 systems (Solaris, IRIX). Ref: server/519.
4349 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4351 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4352 has been updated to use constant array sizes.
4354 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4356 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4357 its generated DWARF Call Frame Info. This encoding was causing GDB to
4358 panic, that panic has been fixed. Ref: gdb/1628.
4360 * Fixed a problem when examining parameters in shared library code.
4362 When examining parameters in optimized shared library code generated
4363 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4364 not available''. GDB now correctly displays the variable's value.
4366 *** Changes in GDB 6.1:
4368 * Removed --with-mmalloc
4370 Support for the mmalloc memory manager has been removed, as it
4371 conflicted with the internal gdb byte cache.
4373 * Changes in AMD64 configurations
4375 The AMD64 target now includes the %cs and %ss registers. As a result
4376 the AMD64 remote protocol has changed; this affects the floating-point
4377 and SSE registers. If you rely on those registers for your debugging,
4378 you should upgrade gdbserver on the remote side.
4380 * Revised SPARC target
4382 The SPARC target has been completely revised, incorporating the
4383 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4384 support for LynxOS and SunOS 4 has been dropped. Calling functions
4385 from within GDB on operating systems with a non-executable stack
4386 (Solaris, OpenBSD) now works.
4390 GDB has a new C++ demangler which does a better job on the mangled
4391 names generated by current versions of g++. It also runs faster, so
4392 with this and other changes gdb should now start faster on large C++
4395 * DWARF 2 Location Expressions
4397 GDB support for location expressions has been extended to support function
4398 arguments and frame bases. Older versions of GDB could crash when they
4401 * C++ nested types and namespaces
4403 GDB's support for nested types and namespaces in C++ has been
4404 improved, especially if you use the DWARF 2 debugging format. (This
4405 is the default for recent versions of GCC on most platforms.)
4406 Specifically, if you have a class "Inner" defined within a class or
4407 namespace "Outer", then GDB realizes that the class's name is
4408 "Outer::Inner", not simply "Inner". This should greatly reduce the
4409 frequency of complaints about not finding RTTI symbols. In addition,
4410 if you are stopped at inside of a function defined within a namespace,
4411 GDB modifies its name lookup accordingly.
4413 * New native configurations
4415 NetBSD/amd64 x86_64-*-netbsd*
4416 OpenBSD/amd64 x86_64-*-openbsd*
4417 OpenBSD/alpha alpha*-*-openbsd*
4418 OpenBSD/sparc sparc-*-openbsd*
4419 OpenBSD/sparc64 sparc64-*-openbsd*
4421 * New debugging protocols
4423 M32R with SDI protocol m32r-*-elf*
4425 * "set prompt-escape-char" command deleted.
4427 The command "set prompt-escape-char" has been deleted. This command,
4428 and its very obscure effet on GDB's prompt, was never documented,
4429 tested, nor mentioned in the NEWS file.
4431 * OBSOLETE configurations and files
4433 Configurations that have been declared obsolete in this release have
4434 been commented out. Unless there is activity to revive these
4435 configurations, the next release of GDB will have their sources
4436 permanently REMOVED.
4438 Sun 3, running SunOS 3 m68*-*-sunos3*
4439 Sun 3, running SunOS 4 m68*-*-sunos4*
4440 Sun 2, running SunOS 3 m68000-*-sunos3*
4441 Sun 2, running SunOS 4 m68000-*-sunos4*
4442 Motorola 680x0 running LynxOS m68*-*-lynxos*
4443 AT&T 3b1/Unix pc m68*-att-*
4444 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4445 decstation mips-dec-* mips-little-*
4446 riscos mips-*-riscos* mips-*-sysv*
4447 sonymips mips-sony-*
4448 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4450 * REMOVED configurations and files
4452 SGI Irix-4.x mips-sgi-irix4 or iris4
4453 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4454 Z8000 simulator z8k-zilog-none or z8ksim
4455 Matsushita MN10200 w/simulator mn10200-*-*
4456 H8/500 simulator h8500-hitachi-hms or h8500hms
4457 HP/PA running BSD hppa*-*-bsd*
4458 HP/PA running OSF/1 hppa*-*-osf*
4459 HP/PA Pro target hppa*-*-pro*
4460 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4461 386BSD i[3456]86-*-bsd*
4462 Sequent family i[3456]86-sequent-sysv4*
4463 i[3456]86-sequent-sysv*
4464 i[3456]86-sequent-bsd*
4465 SPARC running LynxOS sparc-*-lynxos*
4466 SPARC running SunOS 4 sparc-*-sunos4*
4467 Tsqware Sparclet sparclet-*-*
4468 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4470 *** Changes in GDB 6.0:
4474 Support for debugging the Objective-C programming language has been
4475 integrated into GDB.
4477 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4479 DWARF 2's Call Frame Information makes available compiler generated
4480 information that more exactly describes the program's run-time stack.
4481 By using this information, GDB is able to provide more robust stack
4484 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4485 have been updated to use a new backtrace mechanism which includes
4486 DWARF 2 CFI support.
4490 GDB's remote protocol has been extended to include support for hosted
4491 file I/O (where the remote target uses GDB's file system). See GDB's
4492 remote protocol documentation for details.
4494 * All targets using the new architecture framework.
4496 All of GDB's targets have been updated to use the new internal
4497 architecture framework. The way is now open for future GDB releases
4498 to include cross-architecture native debugging support (i386 on amd64,
4501 * GNU/Linux's Thread Local Storage (TLS)
4503 GDB now includes support for for the GNU/Linux implementation of
4504 per-thread variables.
4506 * GNU/Linux's Native POSIX Thread Library (NPTL)
4508 GDB's thread code has been updated to work with either the new
4509 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4511 * Separate debug info.
4513 GDB, in conjunction with BINUTILS, now supports a mechanism for
4514 automatically loading debug information from a separate file. Instead
4515 of shipping full debug and non-debug versions of system libraries,
4516 system integrators can now instead ship just the stripped libraries
4517 and optional debug files.
4519 * DWARF 2 Location Expressions
4521 DWARF 2 Location Expressions allow the compiler to more completely
4522 describe the location of variables (even in optimized code) to the
4525 GDB now includes preliminary support for location expressions (support
4526 for DW_OP_piece is still missing).
4530 A number of long standing bugs that caused GDB to die while starting a
4531 Java application have been fixed. GDB's Java support is now
4532 considered "useable".
4534 * GNU/Linux support for fork, vfork, and exec.
4536 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4537 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4540 * GDB supports logging output to a file
4542 There are two new commands, "set logging" and "show logging", which can be
4543 used to capture GDB's output to a file.
4545 * The meaning of "detach" has changed for gdbserver
4547 The "detach" command will now resume the application, as documented. To
4548 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4551 * d10v, m68hc11 `regs' command deprecated
4553 The `info registers' command has been updated so that it displays the
4554 registers using a format identical to the old `regs' command.
4558 A new command, "maint set profile on/off", has been added. This command can
4559 be used to enable or disable profiling while running GDB, to profile a
4560 session or a set of commands. In addition there is a new configure switch,
4561 "--enable-profiling", which will cause GDB to be compiled with profiling
4562 data, for more informative profiling results.
4564 * Default MI syntax changed to "mi2".
4566 The default MI (machine interface) syntax, enabled by the command line
4567 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4568 "mi1", can be enabled by specifying the option "-i=mi1".
4570 Support for the original "mi0" syntax (included in GDB 5.0) has been
4573 Fix for gdb/192: removed extraneous space when displaying frame level.
4574 Fix for gdb/672: update changelist is now output in mi list format.
4575 Fix for gdb/702: a -var-assign that updates the value now shows up
4576 in a subsequent -var-update.
4578 * New native configurations.
4580 FreeBSD/amd64 x86_64-*-freebsd*
4582 * Multi-arched targets.
4584 HP/PA HPUX11 hppa*-*-hpux*
4585 Renesas M32R/D w/simulator m32r-*-elf*
4587 * OBSOLETE configurations and files
4589 Configurations that have been declared obsolete in this release have
4590 been commented out. Unless there is activity to revive these
4591 configurations, the next release of GDB will have their sources
4592 permanently REMOVED.
4594 Z8000 simulator z8k-zilog-none or z8ksim
4595 Matsushita MN10200 w/simulator mn10200-*-*
4596 H8/500 simulator h8500-hitachi-hms or h8500hms
4597 HP/PA running BSD hppa*-*-bsd*
4598 HP/PA running OSF/1 hppa*-*-osf*
4599 HP/PA Pro target hppa*-*-pro*
4600 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4601 Sequent family i[3456]86-sequent-sysv4*
4602 i[3456]86-sequent-sysv*
4603 i[3456]86-sequent-bsd*
4604 Tsqware Sparclet sparclet-*-*
4605 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4607 * REMOVED configurations and files
4610 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4611 IBM AIX PS/2 i[3456]86-*-aix
4612 i386 running Mach 3.0 i[3456]86-*-mach3*
4613 i386 running Mach i[3456]86-*-mach*
4614 i386 running OSF/1 i[3456]86-*osf1mk*
4615 HP/Apollo 68k Family m68*-apollo*-sysv*,
4617 m68*-hp-bsd*, m68*-hp-hpux*
4618 Argonaut Risc Chip (ARC) arc-*-*
4619 Mitsubishi D30V d30v-*-*
4620 Fujitsu FR30 fr30-*-elf*
4621 OS/9000 i[34]86-*-os9k
4622 I960 with MON960 i960-*-coff
4624 * MIPS $fp behavior changed
4626 The convenience variable $fp, for the MIPS, now consistently returns
4627 the address of the current frame's base. Previously, depending on the
4628 context, $fp could refer to either $sp or the current frame's base
4629 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4630 The GNU Source-Level Debugger''.
4632 *** Changes in GDB 5.3:
4634 * GNU/Linux shared library multi-threaded performance improved.
4636 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4637 `/proc', in preference to `ptrace' for memory reads. This may result
4638 in an improvement in the start-up time of multi-threaded, shared
4639 library applications when run under GDB. One GDB user writes: ``loads
4640 shared libs like mad''.
4642 * ``gdbserver'' now supports multi-threaded applications on some targets
4644 Support for debugging multi-threaded applications which use
4645 the GNU/Linux LinuxThreads package has been added for
4646 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4647 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4649 * GDB now supports C/C++ preprocessor macros.
4651 GDB now expands preprocessor macro invocations in C/C++ expressions,
4652 and provides various commands for showing macro definitions and how
4655 The new command `macro expand EXPRESSION' expands any macro
4656 invocations in expression, and shows the result.
4658 The new command `show macro MACRO-NAME' shows the definition of the
4659 macro named MACRO-NAME, and where it was defined.
4661 Most compilers don't include information about macros in the debugging
4662 information by default. In GCC 3.1, for example, you need to compile
4663 your program with the options `-gdwarf-2 -g3'. If the macro
4664 information is present in the executable, GDB will read it.
4666 * Multi-arched targets.
4668 DEC Alpha (partial) alpha*-*-*
4669 DEC VAX (partial) vax-*-*
4671 National Semiconductor NS32000 (partial) ns32k-*-*
4672 Motorola 68000 (partial) m68k-*-*
4673 Motorola MCORE mcore-*-*
4677 Fujitsu FRV architecture added by Red Hat frv*-*-*
4680 * New native configurations
4682 Alpha NetBSD alpha*-*-netbsd*
4683 SH NetBSD sh*-*-netbsdelf*
4684 MIPS NetBSD mips*-*-netbsd*
4685 UltraSPARC NetBSD sparc64-*-netbsd*
4687 * OBSOLETE configurations and files
4689 Configurations that have been declared obsolete in this release have
4690 been commented out. Unless there is activity to revive these
4691 configurations, the next release of GDB will have their sources
4692 permanently REMOVED.
4694 Mitsubishi D30V d30v-*-*
4695 OS/9000 i[34]86-*-os9k
4696 IBM AIX PS/2 i[3456]86-*-aix
4697 Fujitsu FR30 fr30-*-elf*
4698 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4699 Argonaut Risc Chip (ARC) arc-*-*
4700 i386 running Mach 3.0 i[3456]86-*-mach3*
4701 i386 running Mach i[3456]86-*-mach*
4702 i386 running OSF/1 i[3456]86-*osf1mk*
4703 HP/Apollo 68k Family m68*-apollo*-sysv*,
4705 m68*-hp-bsd*, m68*-hp-hpux*
4706 I960 with MON960 i960-*-coff
4708 * OBSOLETE languages
4710 CHILL, a Pascal like language used by telecommunications companies.
4712 * REMOVED configurations and files
4714 AMD 29k family via UDI a29k-amd-udi, udi29k
4715 A29K VxWorks a29k-*-vxworks
4716 AMD 29000 embedded, using EBMON a29k-none-none
4717 AMD 29000 embedded with COFF a29k-none-coff
4718 AMD 29000 embedded with a.out a29k-none-aout
4720 testsuite/gdb.hp/gdb.threads-hp/ directory
4722 * New command "set max-user-call-depth <nnn>"
4724 This command allows the user to limit the call depth of user-defined
4725 commands. The default is 1024.
4727 * Changes in FreeBSD/i386 native debugging.
4729 Support for the "generate-core-file" has been added.
4731 * New commands "dump", "append", and "restore".
4733 These commands allow data to be copied from target memory
4734 to a bfd-format or binary file (dump and append), and back
4735 from a file into memory (restore).
4737 * Improved "next/step" support on multi-processor Alpha Tru64.
4739 The previous single-step mechanism could cause unpredictable problems,
4740 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4741 of a software single-step mechanism prevents this.
4743 *** Changes in GDB 5.2.1:
4751 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4752 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4753 Fix, by Joel Brobecker imported from mainline.
4755 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4756 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4757 Fix, by Fred Fish, imported from mainline.
4759 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4760 Surprisingly enough, it works now.
4761 By Michal Ludvig, imported from mainline.
4763 i386 hardware watchpoint support:
4764 avoid misses on second run for some targets.
4765 By Pierre Muller, imported from mainline.
4767 *** Changes in GDB 5.2:
4769 * New command "set trust-readonly-sections on[off]".
4771 This command is a hint that tells gdb that read-only sections
4772 really are read-only (ie. that their contents will not change).
4773 In this mode, gdb will go to the object file rather than the
4774 target to read memory from read-only sections (such as ".text").
4775 This can be a significant performance improvement on some
4776 (notably embedded) targets.
4778 * New command "generate-core-file" (or "gcore").
4780 This new gdb command allows the user to drop a core file of the child
4781 process state at any time. So far it's been implemented only for
4782 GNU/Linux and Solaris, but should be relatively easily ported to other
4783 hosts. Argument is core file name (defaults to core.<pid>).
4785 * New command line option
4787 GDB now accepts --pid or -p followed by a process id.
4789 * Change in command line behavior -- corefiles vs. process ids.
4791 There is a subtle behavior in the way in which GDB handles
4792 command line arguments. The first non-flag argument is always
4793 a program to debug, but the second non-flag argument may either
4794 be a corefile or a process id. Previously, GDB would attempt to
4795 open the second argument as a corefile, and if that failed, would
4796 issue a superfluous error message and then attempt to attach it as
4797 a process. Now, if the second argument begins with a non-digit,
4798 it will be treated as a corefile. If it begins with a digit,
4799 GDB will attempt to attach it as a process, and if no such process
4800 is found, will then attempt to open it as a corefile.
4802 * Changes in ARM configurations.
4804 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4805 configuration is fully multi-arch.
4807 * New native configurations
4809 ARM NetBSD arm*-*-netbsd*
4810 x86 OpenBSD i[3456]86-*-openbsd*
4811 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4812 Sparc64 running FreeBSD sparc64-*-freebsd*
4816 Sanyo XStormy16 xstormy16-elf
4818 * OBSOLETE configurations and files
4820 Configurations that have been declared obsolete in this release have
4821 been commented out. Unless there is activity to revive these
4822 configurations, the next release of GDB will have their sources
4823 permanently REMOVED.
4825 AMD 29k family via UDI a29k-amd-udi, udi29k
4826 A29K VxWorks a29k-*-vxworks
4827 AMD 29000 embedded, using EBMON a29k-none-none
4828 AMD 29000 embedded with COFF a29k-none-coff
4829 AMD 29000 embedded with a.out a29k-none-aout
4831 testsuite/gdb.hp/gdb.threads-hp/ directory
4833 * REMOVED configurations and files
4835 TI TMS320C80 tic80-*-*
4837 PowerPC Solaris powerpcle-*-solaris*
4838 PowerPC Windows NT powerpcle-*-cygwin32
4839 PowerPC Netware powerpc-*-netware*
4840 Harris/CXUX m88k m88*-harris-cxux*
4841 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4842 ns32k-utek-sysv* ns32k-utek-*
4843 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4844 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4845 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4846 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4847 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4849 * Changes to command line processing
4851 The new `--args' feature can be used to specify command-line arguments
4852 for the inferior from gdb's command line.
4854 * Changes to key bindings
4856 There is a new `operate-and-get-next' function bound to `C-o'.
4858 *** Changes in GDB 5.1.1
4860 Fix compile problem on DJGPP.
4862 Fix a problem with floating-point registers on the i386 being
4865 Fix to stop GDB crashing on .debug_str debug info.
4867 Numerous documentation fixes.
4869 Numerous testsuite fixes.
4871 *** Changes in GDB 5.1:
4873 * New native configurations
4875 Alpha FreeBSD alpha*-*-freebsd*
4876 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4877 MIPS GNU/Linux mips*-*-linux*
4878 MIPS SGI Irix 6.x mips*-sgi-irix6*
4879 ia64 AIX ia64-*-aix*
4880 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4884 Motorola 68HC11 and 68HC12 m68hc11-elf
4886 UltraSparc running GNU/Linux sparc64-*-linux*
4888 * OBSOLETE configurations and files
4890 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4891 Harris/CXUX m88k m88*-harris-cxux*
4892 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4893 ns32k-utek-sysv* ns32k-utek-*
4894 TI TMS320C80 tic80-*-*
4896 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4897 PowerPC Solaris powerpcle-*-solaris*
4898 PowerPC Windows NT powerpcle-*-cygwin32
4899 PowerPC Netware powerpc-*-netware*
4900 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4901 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4902 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4903 Apple Macintosh (MPW) host N/A
4905 stuff.c (Program to stuff files into a specially prepared space in kdb)
4906 kdb-start.c (Main loop for the standalone kernel debugger)
4908 Configurations that have been declared obsolete in this release have
4909 been commented out. Unless there is activity to revive these
4910 configurations, the next release of GDB will have their sources
4911 permanently REMOVED.
4913 * REMOVED configurations and files
4915 Altos 3068 m68*-altos-*
4916 Convex c1-*-*, c2-*-*
4918 ARM RISCix arm-*-* (as host)
4922 * GDB has been converted to ISO C.
4924 GDB's source code has been converted to ISO C. In particular, the
4925 sources are fully protoized, and rely on standard headers being
4930 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4932 * The MI enabled by default.
4934 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4935 revised and enabled by default. Packages which use GDB as a debugging
4936 engine behind a UI or another front end are encouraged to switch to
4937 using the GDB/MI interface, instead of the old annotations interface
4938 which is now deprecated.
4940 * Support for debugging Pascal programs.
4942 GDB now includes support for debugging Pascal programs. The following
4943 main features are supported:
4945 - Pascal-specific data types such as sets;
4947 - automatic recognition of Pascal sources based on file-name
4950 - Pascal-style display of data types, variables, and functions;
4952 - a Pascal expression parser.
4954 However, some important features are not yet supported.
4956 - Pascal string operations are not supported at all;
4958 - there are some problems with boolean types;
4960 - Pascal type hexadecimal constants are not supported
4961 because they conflict with the internal variables format;
4963 - support for Pascal objects and classes is not full yet;
4965 - unlike Pascal, GDB is case-sensitive for symbol names.
4967 * Changes in completion.
4969 Commands such as `shell', `run' and `set args', which pass arguments
4970 to inferior programs, now complete on file names, similar to what
4971 users expect at the shell prompt.
4973 Commands which accept locations, such as `disassemble', `print',
4974 `breakpoint', `until', etc. now complete on filenames as well as
4975 program symbols. Thus, if you type "break foob TAB", and the source
4976 files linked into the programs include `foobar.c', that file name will
4977 be one of the candidates for completion. However, file names are not
4978 considered for completion after you typed a colon that delimits a file
4979 name from a name of a function in that file, as in "break foo.c:bar".
4981 `set demangle-style' completes on available demangling styles.
4983 * New platform-independent commands:
4985 It is now possible to define a post-hook for a command as well as a
4986 hook that runs before the command. For more details, see the
4987 documentation of `hookpost' in the GDB manual.
4989 * Changes in GNU/Linux native debugging.
4991 Support for debugging multi-threaded programs has been completely
4992 revised for all platforms except m68k and sparc. You can now debug as
4993 many threads as your system allows you to have.
4995 Attach/detach is supported for multi-threaded programs.
4997 Support for SSE registers was added for x86. This doesn't work for
4998 multi-threaded programs though.
5000 * Changes in MIPS configurations.
5002 Multi-arch support is enabled for all MIPS configurations.
5004 GDB can now be built as native debugger on SGI Irix 6.x systems for
5005 debugging n32 executables. (Debugging 64-bit executables is not yet
5008 * Unified support for hardware watchpoints in all x86 configurations.
5010 Most (if not all) native x86 configurations support hardware-assisted
5011 breakpoints and watchpoints in a unified manner. This support
5012 implements debug register sharing between watchpoints, which allows to
5013 put a virtually infinite number of watchpoints on the same address,
5014 and also supports watching regions up to 16 bytes with several debug
5017 The new maintenance command `maintenance show-debug-regs' toggles
5018 debugging print-outs in functions that insert, remove, and test
5019 watchpoints and hardware breakpoints.
5021 * Changes in the DJGPP native configuration.
5023 New command ``info dos sysinfo'' displays assorted information about
5024 the CPU, OS, memory, and DPMI server.
5026 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
5027 display information about segment descriptors stored in GDT, LDT, and
5030 New commands ``info dos pde'' and ``info dos pte'' display entries
5031 from Page Directory and Page Tables (for now works with CWSDPMI only).
5032 New command ``info dos address-pte'' displays the Page Table entry for
5033 a given linear address.
5035 GDB can now pass command lines longer than 126 characters to the
5036 program being debugged (requires an update to the libdbg.a library
5037 which is part of the DJGPP development kit).
5039 DWARF2 debug info is now supported.
5041 It is now possible to `step' and `next' through calls to `longjmp'.
5043 * Changes in documentation.
5045 All GDB documentation was converted to GFDL, the GNU Free
5046 Documentation License.
5048 Tracepoints-related commands are now fully documented in the GDB
5051 TUI, the Text-mode User Interface, is now documented in the manual.
5053 Tracepoints-related commands are now fully documented in the GDB
5056 The "GDB Internals" manual now has an index. It also includes
5057 documentation of `ui_out' functions, GDB coding standards, x86
5058 hardware watchpoints, and memory region attributes.
5060 * GDB's version number moved to ``version.in''
5062 The Makefile variable VERSION has been replaced by the file
5063 ``version.in''. People creating GDB distributions should update the
5064 contents of this file.
5068 GUD support is now a standard part of the EMACS distribution.
5070 *** Changes in GDB 5.0:
5072 * Improved support for debugging FP programs on x86 targets
5074 Unified and much-improved support for debugging floating-point
5075 programs on all x86 targets. In particular, ``info float'' now
5076 displays the FP registers in the same format on all x86 targets, with
5077 greater level of detail.
5079 * Improvements and bugfixes in hardware-assisted watchpoints
5081 It is now possible to watch array elements, struct members, and
5082 bitfields with hardware-assisted watchpoints. Data-read watchpoints
5083 on x86 targets no longer erroneously trigger when the address is
5086 * Improvements in the native DJGPP version of GDB
5088 The distribution now includes all the scripts and auxiliary files
5089 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5090 machines ``out of the box''.
5092 The DJGPP version can now debug programs that use signals. It is
5093 possible to catch signals that happened in the debuggee, deliver
5094 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5095 would kill the program being debugged.) Programs that hook hardware
5096 interrupts (keyboard, timer, etc.) can also be debugged.
5098 It is now possible to debug DJGPP programs that redirect their
5099 standard handles or switch them to raw (as opposed to cooked) mode, or
5100 even close them. The command ``run < foo > bar'' works as expected,
5101 and ``info terminal'' reports useful information about the debuggee's
5102 terminal, including raw/cooked mode, redirection, etc.
5104 The DJGPP version now uses termios functions for console I/O, which
5105 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5108 DOS-style file names with drive letters are now fully supported by
5111 It is now possible to debug DJGPP programs that switch their working
5112 directory. It is also possible to rerun the debuggee any number of
5113 times without restarting GDB; thus, you can use the same setup,
5114 breakpoints, etc. for many debugging sessions.
5116 * New native configurations
5118 ARM GNU/Linux arm*-*-linux*
5119 PowerPC GNU/Linux powerpc-*-linux*
5123 Motorola MCore mcore-*-*
5124 x86 VxWorks i[3456]86-*-vxworks*
5125 PowerPC VxWorks powerpc-*-vxworks*
5126 TI TMS320C80 tic80-*-*
5128 * OBSOLETE configurations
5130 Altos 3068 m68*-altos-*
5131 Convex c1-*-*, c2-*-*
5133 ARM RISCix arm-*-* (as host)
5136 Configurations that have been declared obsolete will be commented out,
5137 but the code will be left in place. If there is no activity to revive
5138 these configurations before the next release of GDB, the sources will
5139 be permanently REMOVED.
5141 * Gould support removed
5143 Support for the Gould PowerNode and NP1 has been removed.
5145 * New features for SVR4
5147 On SVR4 native platforms (such as Solaris), if you attach to a process
5148 without first loading a symbol file, GDB will now attempt to locate and
5149 load symbols from the running process's executable file.
5151 * Many C++ enhancements
5153 C++ support has been greatly improved. Overload resolution now works properly
5154 in almost all cases. RTTI support is on the way.
5156 * Remote targets can connect to a sub-program
5158 A popen(3) style serial-device has been added. This device starts a
5159 sub-process (such as a stand-alone simulator) and then communicates
5160 with that. The sub-program to run is specified using the syntax
5161 ``|<program> <args>'' vis:
5163 (gdb) set remotedebug 1
5164 (gdb) target extended-remote |mn10300-elf-sim program-args
5166 * MIPS 64 remote protocol
5168 A long standing bug in the mips64 remote protocol where by GDB
5169 expected certain 32 bit registers (ex SR) to be transfered as 32
5170 instead of 64 bits has been fixed.
5172 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5173 added to provide backward compatibility with older versions of GDB.
5175 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5177 The command ``set remotebinarydownload'' command has been replaced by
5178 ``set remote X-packet''. Other commands in ``set remote'' family
5179 include ``set remote P-packet''.
5181 * Breakpoint commands accept ranges.
5183 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5184 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5185 ``tracepoint passcount'' also accepts a range of tracepoints.
5187 * ``apropos'' command added.
5189 The ``apropos'' command searches through command names and
5190 documentation strings, printing out matches, making it much easier to
5191 try to find a command that does what you are looking for.
5195 A new machine oriented interface (MI) has been added to GDB. This
5196 interface is designed for debug environments running GDB as a separate
5197 process. This is part of the long term libGDB project. See the
5198 "GDB/MI" chapter of the GDB manual for further information. It can be
5199 enabled by configuring with:
5201 .../configure --enable-gdbmi
5203 *** Changes in GDB-4.18:
5205 * New native configurations
5207 HP-UX 10.20 hppa*-*-hpux10.20
5208 HP-UX 11.x hppa*-*-hpux11.0*
5209 M68K GNU/Linux m68*-*-linux*
5213 Fujitsu FR30 fr30-*-elf*
5214 Intel StrongARM strongarm-*-*
5215 Mitsubishi D30V d30v-*-*
5217 * OBSOLETE configurations
5219 Gould PowerNode, NP1 np1-*-*, pn-*-*
5221 Configurations that have been declared obsolete will be commented out,
5222 but the code will be left in place. If there is no activity to revive
5223 these configurations before the next release of GDB, the sources will
5224 be permanently REMOVED.
5228 As a compatibility experiment, GDB's source files buildsym.h and
5229 buildsym.c have been converted to pure standard C, no longer
5230 containing any K&R compatibility code. We believe that all systems in
5231 use today either come with a standard C compiler, or have a GCC port
5232 available. If this is not true, please report the affected
5233 configuration to bug-gdb@gnu.org immediately. See the README file for
5234 information about getting a standard C compiler if you don't have one
5239 GDB now uses readline 2.2.
5241 * set extension-language
5243 You can now control the mapping between filename extensions and source
5244 languages by using the `set extension-language' command. For instance,
5245 you can ask GDB to treat .c files as C++ by saying
5246 set extension-language .c c++
5247 The command `info extensions' lists all of the recognized extensions
5248 and their associated languages.
5250 * Setting processor type for PowerPC and RS/6000
5252 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5253 you can use the `set processor' command to specify what variant of the
5254 PowerPC family you are debugging. The command
5258 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5259 following PowerPC and RS6000 variants:
5261 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5262 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5264 403GC IBM PowerPC 403GC
5265 505 Motorola PowerPC 505
5266 860 Motorola PowerPC 860 or 850
5267 601 Motorola PowerPC 601
5268 602 Motorola PowerPC 602
5269 603 Motorola/IBM PowerPC 603 or 603e
5270 604 Motorola PowerPC 604 or 604e
5271 750 Motorola/IBM PowerPC 750 or 750
5273 At the moment, this command just tells GDB what to name the
5274 special-purpose processor registers. Since almost all the affected
5275 registers are inaccessible to user-level programs, this command is
5276 only useful for remote debugging in its present form.
5280 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5281 more extensive support for HP-UX. Added features include shared
5282 library support, kernel threads and hardware watchpoints for 11.00,
5283 support for HP's ANSI C and C++ compilers, and a compatibility mode
5284 for xdb and dbx commands.
5288 HP's donation includes the new concept of catchpoints, which is a
5289 generalization of the old catch command. On HP-UX, it is now possible
5290 to catch exec, fork, and vfork, as well as library loading.
5292 This means that the existing catch command has changed; its first
5293 argument now specifies the type of catch to be set up. See the
5294 output of "help catch" for a list of catchpoint types.
5296 * Debugging across forks
5298 On HP-UX, you can choose which process to debug when a fork() happens
5303 HP has donated a curses-based terminal user interface (TUI). To get
5304 it, build with --enable-tui. Although this can be enabled for any
5305 configuration, at present it only works for native HP debugging.
5307 * GDB remote protocol additions
5309 A new protocol packet 'X' that writes binary data is now available.
5310 Default behavior is to try 'X', then drop back to 'M' if the stub
5311 fails to respond. The settable variable `remotebinarydownload'
5312 allows explicit control over the use of 'X'.
5314 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5315 full 64-bit address. The command
5317 set remoteaddresssize 32
5319 can be used to revert to the old behaviour. For existing remote stubs
5320 the change should not be noticed, as the additional address information
5323 In order to assist in debugging stubs, you may use the maintenance
5324 command `packet' to send any text string to the stub. For instance,
5326 maint packet heythere
5328 sends the packet "$heythere#<checksum>". Note that it is very easy to
5329 disrupt a debugging session by sending the wrong packet at the wrong
5332 The compare-sections command allows you to compare section data on the
5333 target to what is in the executable file without uploading or
5334 downloading, by comparing CRC checksums.
5336 * Tracing can collect general expressions
5338 You may now collect general expressions at tracepoints. This requires
5339 further additions to the target-side stub; see tracepoint.c and
5340 doc/agentexpr.texi for further details.
5342 * mask-address variable for Mips
5344 For Mips targets, you may control the zeroing of the upper 32 bits of
5345 a 64-bit address by entering `set mask-address on'. This is mainly
5346 of interest to users of embedded R4xxx and R5xxx processors.
5348 * Higher serial baud rates
5350 GDB's serial code now allows you to specify baud rates 57600, 115200,
5351 230400, and 460800 baud. (Note that your host system may not be able
5352 to achieve all of these rates.)
5356 The i960 configuration now includes an initial implementation of a
5357 builtin simulator, contributed by Jim Wilson.
5360 *** Changes in GDB-4.17:
5362 * New native configurations
5364 Alpha GNU/Linux alpha*-*-linux*
5365 Unixware 2.x i[3456]86-unixware2*
5366 Irix 6.x mips*-sgi-irix6*
5367 PowerPC GNU/Linux powerpc-*-linux*
5368 PowerPC Solaris powerpcle-*-solaris*
5369 Sparc GNU/Linux sparc-*-linux*
5370 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5374 Argonaut Risc Chip (ARC) arc-*-*
5375 Hitachi H8/300S h8300*-*-*
5376 Matsushita MN10200 w/simulator mn10200-*-*
5377 Matsushita MN10300 w/simulator mn10300-*-*
5378 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5379 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5380 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5381 Mitsubishi D10V w/simulator d10v-*-*
5382 Mitsubishi M32R/D w/simulator m32r-*-elf*
5383 Tsqware Sparclet sparclet-*-*
5384 NEC V850 w/simulator v850-*-*
5386 * New debugging protocols
5388 ARM with RDI protocol arm*-*-*
5389 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5390 DDB and LSI variants of PMON protocol mips*-*-*
5391 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5392 PowerPC with SDS protocol powerpc{,le}-*-eabi
5393 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5397 All configurations can now understand and use the DWARF 2 debugging
5398 format. The choice is automatic, if the symbol file contains DWARF 2
5403 GDB now includes basic Java language support. This support is
5404 only useful with Java compilers that produce native machine code.
5406 * solib-absolute-prefix and solib-search-path
5408 For SunOS and SVR4 shared libraries, you may now set the prefix for
5409 loading absolute shared library symbol files, and the search path for
5410 locating non-absolute shared library symbol files.
5412 * Live range splitting
5414 GDB can now effectively debug code for which GCC has performed live
5415 range splitting as part of its optimization. See gdb/doc/LRS for
5416 more details on the expected format of the stabs information.
5420 GDB's support for the GNU Hurd, including thread debugging, has been
5421 updated to work with current versions of the Hurd.
5425 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5426 instruction set. ARM GDB automatically detects when Thumb
5427 instructions are in use, and adjusts disassembly and backtracing
5432 GDB's MIPS target configurations now handle the MIP16 16-bit
5437 GDB now includes support for overlays; if an executable has been
5438 linked such that multiple sections are based at the same address, GDB
5439 will decide which section to use for symbolic info. You can choose to
5440 control the decision manually, using overlay commands, or implement
5441 additional target-side support and use "overlay load-target" to bring
5442 in the overlay mapping. Do "help overlay" for more detail.
5446 The command "info symbol <address>" displays information about
5447 the symbol at the specified address.
5451 The standard remote protocol now includes an extension that allows
5452 asynchronous collection and display of trace data. This requires
5453 extensive support in the target-side debugging stub. Tracing mode
5454 includes a new interaction mode in GDB and new commands: see the
5455 file tracepoint.c for more details.
5459 Configurations for embedded MIPS now include a simulator contributed
5460 by Cygnus Solutions. The simulator supports the instruction sets
5461 of most MIPS variants.
5465 Sparc configurations may now include the ERC32 simulator contributed
5466 by the European Space Agency. The simulator is not built into
5467 Sparc targets by default; configure with --enable-sim to include it.
5471 For target configurations that may include multiple variants of a
5472 basic architecture (such as MIPS and SH), you may now set the
5473 architecture explicitly. "set arch" sets, "info arch" lists
5474 the possible architectures.
5476 *** Changes in GDB-4.16:
5478 * New native configurations
5480 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5481 M68K NetBSD m68k-*-netbsd*
5482 PowerPC AIX 4.x powerpc-*-aix*
5483 PowerPC MacOS powerpc-*-macos*
5484 PowerPC Windows NT powerpcle-*-cygwin32
5485 RS/6000 AIX 4.x rs6000-*-aix4*
5489 ARM with RDP protocol arm-*-*
5490 I960 with MON960 i960-*-coff
5491 MIPS VxWorks mips*-*-vxworks*
5492 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5493 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5495 Matra Sparclet sparclet-*-*
5499 The powerpc-eabi configuration now includes the PSIM simulator,
5500 contributed by Andrew Cagney, with assistance from Mike Meissner.
5501 PSIM is a very elaborate model of the PowerPC, including not only
5502 basic instruction set execution, but also details of execution unit
5503 performance and I/O hardware. See sim/ppc/README for more details.
5507 GDB now works with Solaris 2.5.
5509 * Windows 95/NT native
5511 GDB will now work as a native debugger on Windows 95 and Windows NT.
5512 To build it from source, you must use the "gnu-win32" environment,
5513 which uses a DLL to emulate enough of Unix to run the GNU tools.
5514 Further information, binaries, and sources are available at
5515 ftp.cygnus.com, under pub/gnu-win32.
5517 * dont-repeat command
5519 If a user-defined command includes the command `dont-repeat', then the
5520 command will not be repeated if the user just types return. This is
5521 useful if the command is time-consuming to run, so that accidental
5522 extra keystrokes don't run the same command many times.
5524 * Send break instead of ^C
5526 The standard remote protocol now includes an option to send a break
5527 rather than a ^C to the target in order to interrupt it. By default,
5528 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5530 * Remote protocol timeout
5532 The standard remote protocol includes a new variable `remotetimeout'
5533 that allows you to set the number of seconds before GDB gives up trying
5534 to read from the target. The default value is 2.
5536 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5538 By default GDB will automatically keep track of objects as they are
5539 loaded and unloaded by the dynamic linker. By using the command `set
5540 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5541 when shared library events occur, thus allowing you to set breakpoints
5542 in shared libraries which are explicitly loaded by the inferior.
5544 Note this feature does not work on hpux8. On hpux9 you must link
5545 /usr/lib/end.o into your program. This feature should work
5546 automatically on hpux10.
5548 * Irix 5.x hardware watchpoint support
5550 Irix 5 configurations now support the use of hardware watchpoints.
5552 * Mips protocol "SYN garbage limit"
5554 When debugging a Mips target using the `target mips' protocol, you
5555 may set the number of characters that GDB will ignore by setting
5556 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5557 every character. The default value is 1050.
5559 * Recording and replaying remote debug sessions
5561 If you set `remotelogfile' to the name of a file, gdb will write to it
5562 a recording of a remote debug session. This recording may then be
5563 replayed back to gdb using "gdbreplay". See gdbserver/README for
5564 details. This is useful when you have a problem with GDB while doing
5565 remote debugging; you can make a recording of the session and send it
5566 to someone else, who can then recreate the problem.
5568 * Speedups for remote debugging
5570 GDB includes speedups for downloading and stepping MIPS systems using
5571 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5572 and more efficient S-record downloading.
5574 * Memory use reductions and statistics collection
5576 GDB now uses less memory and reports statistics about memory usage.
5577 Try the `maint print statistics' command, for example.
5579 *** Changes in GDB-4.15:
5581 * Psymtabs for XCOFF
5583 The symbol reader for AIX GDB now uses partial symbol tables. This
5584 can greatly improve startup time, especially for large executables.
5586 * Remote targets use caching
5588 Remote targets now use a data cache to speed up communication with the
5589 remote side. The data cache could lead to incorrect results because
5590 it doesn't know about volatile variables, thus making it impossible to
5591 debug targets which use memory mapped I/O devices. `set remotecache
5592 off' turns the the data cache off.
5594 * Remote targets may have threads
5596 The standard remote protocol now includes support for multiple threads
5597 in the target system, using new protocol commands 'H' and 'T'. See
5598 gdb/remote.c for details.
5602 If GDB is configured with `--enable-netrom', then it will include
5603 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5604 acts as though it is a bank of ROM on the target board, but you can
5605 write into it over the network. GDB's support consists only of
5606 support for fast loading into the emulated ROM; to debug, you must use
5607 another protocol, such as standard remote protocol. The usual
5608 sequence is something like
5610 target nrom <netrom-hostname>
5612 target remote <netrom-hostname>:1235
5616 GDB now includes support for the Apple Macintosh, as a host only. It
5617 may be run as either an MPW tool or as a standalone application, and
5618 it can debug through the serial port. All the usual GDB commands are
5619 available, but to the target command, you must supply "serial" as the
5620 device type instead of "/dev/ttyXX". See mpw-README in the main
5621 directory for more information on how to build. The MPW configuration
5622 scripts */mpw-config.in support only a few targets, and only the
5623 mips-idt-ecoff target has been tested.
5627 GDB configuration now uses autoconf. This is not user-visible,
5628 but does simplify configuration and building.
5632 GDB now supports hpux10.
5634 *** Changes in GDB-4.14:
5636 * New native configurations
5638 x86 FreeBSD i[345]86-*-freebsd
5639 x86 NetBSD i[345]86-*-netbsd
5640 NS32k NetBSD ns32k-*-netbsd
5641 Sparc NetBSD sparc-*-netbsd
5645 A29K VxWorks a29k-*-vxworks
5646 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5647 CPU32 EST-300 emulator m68*-*-est*
5648 PowerPC ELF powerpc-*-elf
5651 * Alpha OSF/1 support for procfs
5653 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5654 possible to attach to running processes. As the mounting of the /proc
5655 filesystem is optional on the Alpha, GDB automatically determines
5656 the availability of /proc during startup. This can lead to problems
5657 if /proc is unmounted after GDB has been started.
5659 * Arguments to user-defined commands
5661 User commands may accept up to 10 arguments separated by whitespace.
5662 Arguments are accessed within the user command via $arg0..$arg9. A
5665 print $arg0 + $arg1 + $arg2
5667 To execute the command use:
5670 Defines the command "adder" which prints the sum of its three arguments.
5671 Note the arguments are text substitutions, so they may reference variables,
5672 use complex expressions, or even perform inferior function calls.
5674 * New `if' and `while' commands
5676 This makes it possible to write more sophisticated user-defined
5677 commands. Both commands take a single argument, which is the
5678 expression to evaluate, and must be followed by the commands to
5679 execute, one per line, if the expression is nonzero, the list being
5680 terminated by the word `end'. The `if' command list may include an
5681 `else' word, which causes the following commands to be executed only
5682 if the expression is zero.
5684 * Fortran source language mode
5686 GDB now includes partial support for Fortran 77. It will recognize
5687 Fortran programs and can evaluate a subset of Fortran expressions, but
5688 variables and functions may not be handled correctly. GDB will work
5689 with G77, but does not yet know much about symbols emitted by other
5692 * Better HPUX support
5694 Most debugging facilities now work on dynamic executables for HPPAs
5695 running hpux9 or later. You can attach to running dynamically linked
5696 processes, but by default the dynamic libraries will be read-only, so
5697 for instance you won't be able to put breakpoints in them. To change
5698 that behavior do the following before running the program:
5704 This will cause the libraries to be mapped private and read-write.
5705 To revert to the normal behavior, do this:
5711 You cannot set breakpoints or examine data in the library until after
5712 the library is loaded if the function/data symbols do not have
5715 GDB can now also read debug symbols produced by the HP C compiler on
5716 HPPAs (sorry, no C++, Fortran or 68k support).
5718 * Target byte order now dynamically selectable
5720 You can choose which byte order to use with a target system, via the
5721 commands "set endian big" and "set endian little", and you can see the
5722 current setting by using "show endian". You can also give the command
5723 "set endian auto", in which case GDB will use the byte order
5724 associated with the executable. Currently, only embedded MIPS
5725 configurations support dynamic selection of target byte order.
5727 * New DOS host serial code
5729 This version uses DPMI interrupts to handle buffered I/O, so you
5730 no longer need to run asynctsr when debugging boards connected to
5733 *** Changes in GDB-4.13:
5735 * New "complete" command
5737 This lists all the possible completions for the rest of the line, if it
5738 were to be given as a command itself. This is intended for use by emacs.
5740 * Trailing space optional in prompt
5742 "set prompt" no longer adds a space for you after the prompt you set. This
5743 allows you to set a prompt which ends in a space or one that does not.
5745 * Breakpoint hit counts
5747 "info break" now displays a count of the number of times the breakpoint
5748 has been hit. This is especially useful in conjunction with "ignore"; you
5749 can ignore a large number of breakpoint hits, look at the breakpoint info
5750 to see how many times the breakpoint was hit, then run again, ignoring one
5751 less than that number, and this will get you quickly to the last hit of
5754 * Ability to stop printing at NULL character
5756 "set print null-stop" will cause GDB to stop printing the characters of
5757 an array when the first NULL is encountered. This is useful when large
5758 arrays actually contain only short strings.
5760 * Shared library breakpoints
5762 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5763 breakpoints in shared libraries before the executable is run.
5765 * Hardware watchpoints
5767 There is a new hardware breakpoint for the watch command for sparclite
5768 targets. See gdb/sparclite/hw_breakpoint.note.
5770 Hardware watchpoints are also now supported under GNU/Linux.
5774 Annotations have been added. These are for use with graphical interfaces,
5775 and are still experimental. Currently only gdba.el uses these.
5777 * Improved Irix 5 support
5779 GDB now works properly with Irix 5.2.
5781 * Improved HPPA support
5783 GDB now works properly with the latest GCC and GAS.
5785 * New native configurations
5787 Sequent PTX4 i[34]86-sequent-ptx4
5788 HPPA running OSF/1 hppa*-*-osf*
5789 Atari TT running SVR4 m68*-*-sysv4*
5790 RS/6000 LynxOS rs6000-*-lynxos*
5794 OS/9000 i[34]86-*-os9k
5795 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5798 * Hitachi SH7000 and E7000-PC ICE support
5800 There is now support for communicating with the Hitachi E7000-PC ICE.
5801 This is available automatically when GDB is configured for the SH.
5805 As usual, a variety of small fixes and improvements, both generic
5806 and configuration-specific. See the ChangeLog for more detail.
5808 *** Changes in GDB-4.12:
5810 * Irix 5 is now supported
5814 GDB-4.12 on the HPPA has a number of changes which make it unable
5815 to debug the output from the currently released versions of GCC and
5816 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5817 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5818 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5821 *** Changes in GDB-4.11:
5823 * User visible changes:
5827 The "set remotedebug" option is now consistent between the mips remote
5828 target, remote targets using the gdb-specific protocol, UDI (AMD's
5829 debug protocol for the 29k) and the 88k bug monitor. It is now an
5830 integer specifying a debug level (normally 0 or 1, but 2 means more
5831 debugging info for the mips target).
5833 * DEC Alpha native support
5835 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5836 debug info, but GDB works fairly well with the DEC compiler and should
5837 work with a future GCC release. See the README file for a few
5838 Alpha-specific notes.
5840 * Preliminary thread implementation
5842 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5844 * LynxOS native and target support for 386
5846 This release has been hosted on LynxOS 2.2, and also can be configured
5847 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5850 * Improvements in C++ mangling/demangling.
5852 This release has much better g++ debugging, specifically in name
5853 mangling/demangling, virtual function calls, print virtual table,
5854 call methods, ...etc.
5856 *** Changes in GDB-4.10:
5858 * User visible changes:
5860 Remote debugging using the GDB-specific (`target remote') protocol now
5861 supports the `load' command. This is only useful if you have some
5862 other way of getting the stub to the target system, and you can put it
5863 somewhere in memory where it won't get clobbered by the download.
5865 Filename completion now works.
5867 When run under emacs mode, the "info line" command now causes the
5868 arrow to point to the line specified. Also, "info line" prints
5869 addresses in symbolic form (as well as hex).
5871 All vxworks based targets now support a user settable option, called
5872 vxworks-timeout. This option represents the number of seconds gdb
5873 should wait for responses to rpc's. You might want to use this if
5874 your vxworks target is, perhaps, a slow software simulator or happens
5875 to be on the far side of a thin network line.
5879 This release contains support for using a DEC alpha as a GDB host for
5880 cross debugging. Native alpha debugging is not supported yet.
5883 *** Changes in GDB-4.9:
5887 This is the first GDB release which is accompanied by a matching testsuite.
5888 The testsuite requires installation of dejagnu, which should be available
5889 via ftp from most sites that carry GNU software.
5893 'Cfront' style demangling has had its name changed to 'ARM' style, to
5894 emphasize that it was written from the specifications in the C++ Annotated
5895 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5896 disclaimers, it still generated too much confusion with users attempting to
5897 use gdb with AT&T cfront.
5901 GDB now uses a standard remote interface to a simulator library.
5902 So far, the library contains simulators for the Zilog Z8001/2, the
5903 Hitachi H8/300, H8/500 and Super-H.
5905 * New targets supported
5907 H8/300 simulator h8300-hitachi-hms or h8300hms
5908 H8/500 simulator h8500-hitachi-hms or h8500hms
5909 SH simulator sh-hitachi-hms or sh
5910 Z8000 simulator z8k-zilog-none or z8ksim
5911 IDT MIPS board over serial line mips-idt-ecoff
5913 Cross-debugging to GO32 targets is supported. It requires a custom
5914 version of the i386-stub.c module which is integrated with the
5915 GO32 memory extender.
5917 * New remote protocols
5919 MIPS remote debugging protocol.
5921 * New source languages supported
5923 This version includes preliminary support for Chill, a Pascal like language
5924 used by telecommunications companies. Chill support is also being integrated
5925 into the GNU compiler, but we don't know when it will be publically available.
5928 *** Changes in GDB-4.8:
5930 * HP Precision Architecture supported
5932 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5933 version of this support was available as a set of patches from the
5934 University of Utah. GDB does not support debugging of programs
5935 compiled with the HP compiler, because HP will not document their file
5936 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5937 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5939 Many problems in the preliminary version have been fixed.
5941 * Faster and better demangling
5943 We have improved template demangling and fixed numerous bugs in the GNU style
5944 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5945 character types (wchar_t) are now supported. Demangling of each symbol is now
5946 only done once, and is cached when the symbol table for a file is read in.
5947 This results in a small increase in memory usage for C programs, a moderate
5948 increase in memory usage for C++ programs, and a fantastic speedup in
5951 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5952 from the specifications in the Annotated Reference Manual, which AT&T's
5953 compiler does not actually implement.
5955 * G++ multiple inheritance compiler problem
5957 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5958 inheritance lattices was reworked to properly discover ambiguities. We
5959 recently found an example which causes this new algorithm to fail in a
5960 very subtle way, producing bad debug information for those classes.
5961 The file 'gcc.patch' (in this directory) can be applied to gcc to
5962 circumvent the problem. A future GCC release will contain a complete
5965 The previous G++ debug info problem (mentioned below for the gdb-4.7
5966 release) is fixed in gcc version 2.3.2.
5968 * Improved configure script
5970 The `configure' script will now attempt to guess your system type if
5971 you don't supply a host system type. The old scheme of supplying a
5972 host system triplet is preferable over using this. All the magic is
5973 done in the new `config.guess' script. Examine it for details.
5975 We have also brought our configure script much more in line with the FSF's
5976 version. It now supports the --with-xxx options. In particular,
5977 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5978 The resulting GDB will not be able to read arbitrary object file formats --
5979 only the format ``expected'' to be used on the configured target system.
5980 We hope to make this the default in a future release.
5982 * Documentation improvements
5984 There's new internal documentation on how to modify GDB, and how to
5985 produce clean changes to the code. We implore people to read it
5986 before submitting changes.
5988 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5989 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5990 `info' files are also provided. To build `info' files from scratch,
5991 you will need the latest `makeinfo' release, which will be available in
5992 a future texinfo-X.Y release.
5994 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5995 We're not sure exactly which versions have this problem, but it has
5996 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5997 or better. If that isn't possible, there is a patch in
5998 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5999 around this problem.
6003 GDB now supports array constants that can be used in expressions typed in by
6004 the user. The syntax is `{element, element, ...}'. Ie: you can now type
6005 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
6008 The new directory `gdb/sparclite' contains a program that demonstrates
6009 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
6011 * New native hosts supported
6013 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
6014 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
6016 * New targets supported
6018 AMD 29k family via UDI a29k-amd-udi or udi29k
6020 * New file formats supported
6022 BFD now supports reading HP/PA-RISC executables (SOM file format?),
6023 HPUX core files, and SCO 3.2v2 core files.
6027 Attaching to processes now works again; thanks for the many bug reports.
6029 We have also stomped on a bunch of core dumps caused by
6030 printf_filtered("%s") problems.
6032 We eliminated a copyright problem on the rpc and ptrace header files
6033 for VxWorks, which was discovered at the last minute during the 4.7
6034 release. You should now be able to build a VxWorks GDB.
6036 You can now interrupt gdb while an attached process is running. This
6037 will cause the attached process to stop, and give control back to GDB.
6039 We fixed problems caused by using too many file descriptors
6040 for reading symbols from object files and libraries. This was
6041 especially a problem for programs that used many (~100) shared
6044 The `step' command now only enters a subroutine if there is line number
6045 information for the subroutine. Otherwise it acts like the `next'
6046 command. Previously, `step' would enter subroutines if there was
6047 any debugging information about the routine. This avoids problems
6048 when using `cc -g1' on MIPS machines.
6050 * Internal improvements
6052 GDB's internal interfaces have been improved to make it easier to support
6053 debugging of multiple languages in the future.
6055 GDB now uses a common structure for symbol information internally.
6056 Minimal symbols (derived from linkage symbols in object files), partial
6057 symbols (from a quick scan of debug information), and full symbols
6058 contain a common subset of information, making it easier to write
6059 shared code that handles any of them.
6061 * New command line options
6063 We now accept --silent as an alias for --quiet.
6067 The memory-mapped-malloc library is now licensed under the GNU Library
6068 General Public License.
6070 *** Changes in GDB-4.7:
6072 * Host/native/target split
6074 GDB has had some major internal surgery to untangle the support for
6075 hosts and remote targets. Now, when you configure GDB for a remote
6076 target, it will no longer load in all of the support for debugging
6077 local programs on the host. When fully completed and tested, this will
6078 ensure that arbitrary host/target combinations are possible.
6080 The primary conceptual shift is to separate the non-portable code in
6081 GDB into three categories. Host specific code is required any time GDB
6082 is compiled on that host, regardless of the target. Target specific
6083 code relates to the peculiarities of the target, but can be compiled on
6084 any host. Native specific code is everything else: it can only be
6085 built when the host and target are the same system. Child process
6086 handling and core file support are two common `native' examples.
6088 GDB's use of /proc for controlling Unix child processes is now cleaner.
6089 It has been split out into a single module under the `target_ops' vector,
6090 plus two native-dependent functions for each system that uses /proc.
6092 * New hosts supported
6094 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6095 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6096 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6098 * New targets supported
6100 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6101 68030 and CPU32 m68030-*-*, m68332-*-*
6103 * New native hosts supported
6105 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6106 (386bsd is not well tested yet)
6107 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6109 * New file formats supported
6111 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6112 supports reading of `a.out.adobe' object files, which are an a.out
6113 format extended with minimal information about multiple sections.
6117 `show copying' is the same as the old `info copying'.
6118 `show warranty' is the same as `info warrantee'.
6119 These were renamed for consistency. The old commands continue to work.
6121 `info handle' is a new alias for `info signals'.
6123 You can now define pre-command hooks, which attach arbitrary command
6124 scripts to any command. The commands in the hook will be executed
6125 prior to the user's command. You can also create a hook which will be
6126 executed whenever the program stops. See gdb.texinfo.
6130 We now deal with Cfront style name mangling, and can even extract type
6131 info from mangled symbols. GDB can automatically figure out which
6132 symbol mangling style your C++ compiler uses.
6134 Calling of methods and virtual functions has been improved as well.
6138 The crash that occured when debugging Sun Ansi-C compiled binaries is
6139 fixed. This was due to mishandling of the extra N_SO stabs output
6142 We also finally got Ultrix 4.2 running in house, and fixed core file
6143 support, with help from a dozen people on the net.
6145 John M. Farrell discovered that the reason that single-stepping was so
6146 slow on all of the Mips based platforms (primarily SGI and DEC) was
6147 that we were trying to demangle and lookup a symbol used for internal
6148 purposes on every instruction that was being stepped through. Changing
6149 the name of that symbol so that it couldn't be mistaken for a C++
6150 mangled symbol sped things up a great deal.
6152 Rich Pixley sped up symbol lookups in general by getting much smarter
6153 about when C++ symbol mangling is necessary. This should make symbol
6154 completion (TAB on the command line) much faster. It's not as fast as
6155 we'd like, but it's significantly faster than gdb-4.6.
6159 A new user controllable variable 'call_scratch_address' can
6160 specify the location of a scratch area to be used when GDB
6161 calls a function in the target. This is necessary because the
6162 usual method of putting the scratch area on the stack does not work
6163 in systems that have separate instruction and data spaces.
6165 We integrated changes to support the 29k UDI (Universal Debugger
6166 Interface), but discovered at the last minute that we didn't have all
6167 of the appropriate copyright paperwork. We are working with AMD to
6168 resolve this, and hope to have it available soon.
6172 We have sped up the remote serial line protocol, especially for targets
6173 with lots of registers. It now supports a new `expedited status' ('T')
6174 message which can be used in place of the existing 'S' status message.
6175 This allows the remote stub to send only the registers that GDB
6176 needs to make a quick decision about single-stepping or conditional
6177 breakpoints, eliminating the need to fetch the entire register set for
6178 each instruction being stepped through.
6180 The GDB remote serial protocol now implements a write-through cache for
6181 registers, only re-reading the registers if the target has run.
6183 There is also a new remote serial stub for SPARC processors. You can
6184 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6185 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6186 processor with a serial port.
6190 Configure.in files have become much easier to read and modify. A new
6191 `table driven' format makes it more obvious what configurations are
6192 supported, and what files each one uses.
6196 There is a new opcodes library which will eventually contain all of the
6197 disassembly routines and opcode tables. At present, it only contains
6198 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6199 disassembler (binutils/objdump) to share these routines.
6201 The libiberty library is now copylefted under the GNU Library General
6202 Public License. This allows more liberal use, and was done so libg++
6203 can use it. This makes no difference to GDB, since the Library License
6204 grants all the rights from the General Public License.
6208 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6209 reference to the stabs symbol info used by the debugger. It is (as far
6210 as we know) the only published document on this fascinating topic. We
6211 encourage you to read it, compare it to the stabs information on your
6212 system, and send improvements on the document in general (to
6213 bug-gdb@prep.ai.mit.edu).
6215 And, of course, many bugs have been fixed.
6218 *** Changes in GDB-4.6:
6220 * Better support for C++ function names
6222 GDB now accepts as input the "demangled form" of C++ overloaded function
6223 names and member function names, and can do command completion on such names
6224 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6225 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6226 Make use of command completion, it is your friend.
6228 GDB also now accepts a variety of C++ mangled symbol formats. They are
6229 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6230 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6231 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6232 for the list of formats.
6234 * G++ symbol mangling problem
6236 Recent versions of gcc have a bug in how they emit debugging information for
6237 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6238 directory) can be applied to gcc to fix the problem. Alternatively, if you
6239 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6240 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6241 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6244 * New 'maintenance' command
6246 All of the commands related to hacking GDB internals have been moved out of
6247 the main command set, and now live behind the 'maintenance' command. This
6248 can also be abbreviated as 'mt'. The following changes were made:
6250 dump-me -> maintenance dump-me
6251 info all-breakpoints -> maintenance info breakpoints
6252 printmsyms -> maintenance print msyms
6253 printobjfiles -> maintenance print objfiles
6254 printpsyms -> maintenance print psymbols
6255 printsyms -> maintenance print symbols
6257 The following commands are new:
6259 maintenance demangle Call internal GDB demangler routine to
6260 demangle a C++ link name and prints the result.
6261 maintenance print type Print a type chain for a given symbol
6263 * Change to .gdbinit file processing
6265 We now read the $HOME/.gdbinit file before processing the argv arguments
6266 (e.g. reading symbol files or core files). This allows global parameters to
6267 be set, which will apply during the symbol reading. The ./.gdbinit is still
6268 read after argv processing.
6270 * New hosts supported
6272 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6274 GNU/Linux support i386-unknown-linux or linux
6276 We are also including code to support the HP/PA running BSD and HPUX. This
6277 is almost guaranteed not to work, as we didn't have time to test or build it
6278 for this release. We are including it so that the more adventurous (or
6279 masochistic) of you can play with it. We also had major problems with the
6280 fact that the compiler that we got from HP doesn't support the -g option.
6283 * New targets supported
6285 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6287 * More smarts about finding #include files
6289 GDB now remembers the compilation directory for all include files, and for
6290 all files from which C is generated (like yacc and lex sources). This
6291 greatly improves GDB's ability to find yacc/lex sources, and include files,
6292 especially if you are debugging your program from a directory different from
6293 the one that contains your sources.
6295 We also fixed a bug which caused difficulty with listing and setting
6296 breakpoints in include files which contain C code. (In the past, you had to
6297 try twice in order to list an include file that you hadn't looked at before.)
6299 * Interesting infernals change
6301 GDB now deals with arbitrary numbers of sections, where the symbols for each
6302 section must be relocated relative to that section's landing place in the
6303 target's address space. This work was needed to support ELF with embedded
6304 stabs used by Solaris-2.0.
6306 * Bug fixes (of course!)
6308 There have been loads of fixes for the following things:
6309 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6310 i960, stabs, DOS(GO32), procfs, etc...
6312 See the ChangeLog for details.
6314 *** Changes in GDB-4.5:
6316 * New machines supported (host and target)
6318 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6320 SGI Irix-4.x mips-sgi-irix4 or iris4
6322 * New malloc package
6324 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6325 Mmalloc is capable of handling mutiple heaps of memory. It is also
6326 capable of saving a heap to a file, and then mapping it back in later.
6327 This can be used to greatly speedup the startup of GDB by using a
6328 pre-parsed symbol table which lives in a mmalloc managed heap. For
6329 more details, please read mmalloc/mmalloc.texi.
6333 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6334 'help info proc' for details.
6336 * MIPS ecoff symbol table format
6338 The code that reads MIPS symbol table format is now supported on all hosts.
6339 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6342 * File name changes for MS-DOS
6344 Many files in the config directories have been renamed to make it easier to
6345 support GDB on MS-DOSe systems (which have very restrictive file name
6346 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6347 environment) is close to working but has some remaining problems. Note
6348 that debugging of DOS programs is not supported, due to limitations
6349 in the ``operating system'', but it can be used to host cross-debugging.
6351 * Cross byte order fixes
6353 Many fixes have been made to support cross debugging of Sparc and MIPS
6354 targets from hosts whose byte order differs.
6356 * New -mapped and -readnow options
6358 If memory-mapped files are available on your system through the 'mmap'
6359 system call, you can use the -mapped option on the `file' or
6360 `symbol-file' commands to cause GDB to write the symbols from your
6361 program into a reusable file. If the program you are debugging is
6362 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6363 Future GDB debugging sessions will notice the presence of this file,
6364 and will quickly map in symbol information from it, rather than reading
6365 the symbol table from the executable program. Using the '-mapped'
6366 option in a GDB `file' or `symbol-file' command has the same effect as
6367 starting GDB with the '-mapped' command-line option.
6369 You can cause GDB to read the entire symbol table immediately by using
6370 the '-readnow' option with any of the commands that load symbol table
6371 information (or on the GDB command line). This makes the command
6372 slower, but makes future operations faster.
6374 The -mapped and -readnow options are typically combined in order to
6375 build a `fred.syms' file that contains complete symbol information.
6376 A simple GDB invocation to do nothing but build a `.syms' file for future
6379 gdb -batch -nx -mapped -readnow programname
6381 The `.syms' file is specific to the host machine on which GDB is run.
6382 It holds an exact image of GDB's internal symbol table. It cannot be
6383 shared across multiple host platforms.
6385 * longjmp() handling
6387 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6388 siglongjmp() without losing control. This feature has not yet been ported to
6389 all systems. It currently works on many 386 platforms, all MIPS-based
6390 platforms (SGI, DECstation, etc), and Sun3/4.
6394 Preliminary work has been put in to support the new Solaris OS from Sun. At
6395 this time, it can control and debug processes, but it is not capable of
6400 As always, many many bug fixes. The major areas were with g++, and mipsread.
6401 People using the MIPS-based platforms should experience fewer mysterious
6402 crashes and trashed symbol tables.
6404 *** Changes in GDB-4.4:
6406 * New machines supported (host and target)
6408 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6410 BSD Reno on Vax vax-dec-bsd
6411 Ultrix on Vax vax-dec-ultrix
6413 * New machines supported (target)
6415 AMD 29000 embedded, using EBMON a29k-none-none
6419 GDB continues to improve its handling of C++. `References' work better.
6420 The demangler has also been improved, and now deals with symbols mangled as
6421 per the Annotated C++ Reference Guide.
6423 GDB also now handles `stabs' symbol information embedded in MIPS
6424 `ecoff' symbol tables. Since the ecoff format was not easily
6425 extensible to handle new languages such as C++, this appeared to be a
6426 good way to put C++ debugging info into MIPS binaries. This option
6427 will be supported in the GNU C compiler, version 2, when it is
6430 * New features for SVR4
6432 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6433 shared libraries. Debugging dynamically linked programs should present
6434 only minor differences from debugging statically linked programs.
6436 The `info proc' command will print out information about any process
6437 on an SVR4 system (including the one you are debugging). At the moment,
6438 it prints the address mappings of the process.
6440 If you bring up GDB on another SVR4 system, please send mail to
6441 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6443 * Better dynamic linking support in SunOS
6445 Reading symbols from shared libraries which contain debugging symbols
6446 now works properly. However, there remain issues such as automatic
6447 skipping of `transfer vector' code during function calls, which
6448 make it harder to debug code in a shared library, than to debug the
6449 same code linked statically.
6453 GDB is now using the latest `getopt' routines from the FSF. This
6454 version accepts the -- prefix for options with long names. GDB will
6455 continue to accept the old forms (-option and +option) as well.
6456 Various single letter abbreviations for options have been explicity
6457 added to the option table so that they won't get overshadowed in the
6458 future by other options that begin with the same letter.
6462 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6463 Many assorted bugs have been handled. Many more remain to be handled.
6464 See the various ChangeLog files (primarily in gdb and bfd) for details.
6467 *** Changes in GDB-4.3:
6469 * New machines supported (host and target)
6471 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6472 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6473 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6475 * Almost SCO Unix support
6477 We had hoped to support:
6478 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6479 (except for core file support), but we discovered very late in the release
6480 that it has problems with process groups that render gdb unusable. Sorry
6481 about that. I encourage people to fix it and post the fixes.
6483 * Preliminary ELF and DWARF support
6485 GDB can read ELF object files on System V Release 4, and can handle
6486 debugging records for C, in DWARF format, in ELF files. This support
6487 is preliminary. If you bring up GDB on another SVR4 system, please
6488 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6493 GDB now uses the latest `readline' library. One user-visible change
6494 is that two tabs will list possible command completions, which previously
6495 required typing M-? (meta-question mark, or ESC ?).
6499 The `stepi' bug that many of you noticed has been squashed.
6500 Many bugs in C++ have been handled. Many more remain to be handled.
6501 See the various ChangeLog files (primarily in gdb and bfd) for details.
6503 * State of the MIPS world (in case you wondered):
6505 GDB can understand the symbol tables emitted by the compilers
6506 supplied by most vendors of MIPS-based machines, including DEC. These
6507 symbol tables are in a format that essentially nobody else uses.
6509 Some versions of gcc come with an assembler post-processor called
6510 mips-tfile. This program is required if you want to do source-level
6511 debugging of gcc-compiled programs. I believe FSF does not ship
6512 mips-tfile with gcc version 1, but it will eventually come with gcc
6515 Debugging of g++ output remains a problem. g++ version 1.xx does not
6516 really support it at all. (If you're lucky, you should be able to get
6517 line numbers and stack traces to work, but no parameters or local
6518 variables.) With some work it should be possible to improve the
6521 When gcc version 2 is released, you will have somewhat better luck.
6522 However, even then you will get confusing results for inheritance and
6525 We will eventually provide full debugging of g++ output on
6526 DECstations. This will probably involve some kind of stabs-in-ecoff
6527 encapulation, but the details have not been worked out yet.
6530 *** Changes in GDB-4.2:
6532 * Improved configuration
6534 Only one copy of `configure' exists now, and it is not self-modifying.
6535 Porting BFD is simpler.
6539 The `step' and `next' commands now only stop at the first instruction
6540 of a source line. This prevents the multiple stops that used to occur
6541 in switch statements, for-loops, etc. `Step' continues to stop if a
6542 function that has debugging information is called within the line.
6546 Lots of small bugs fixed. More remain.
6548 * New host supported (not target)
6550 Intel 386 PC clone running Mach i386-none-mach
6553 *** Changes in GDB-4.1:
6555 * Multiple source language support
6557 GDB now has internal scaffolding to handle several source languages.
6558 It determines the type of each source file from its filename extension,
6559 and will switch expression parsing and number formatting to match the
6560 language of the function in the currently selected stack frame.
6561 You can also specifically set the language to be used, with
6562 `set language c' or `set language modula-2'.
6566 GDB now has preliminary support for the GNU Modula-2 compiler,
6567 currently under development at the State University of New York at
6568 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6569 continue through the fall of 1991 and into 1992.
6571 Other Modula-2 compilers are currently not supported, and attempting to
6572 debug programs compiled with them will likely result in an error as the
6573 symbol table is read. Feel free to work on it, though!
6575 There are hooks in GDB for strict type checking and range checking,
6576 in the `Modula-2 philosophy', but they do not currently work.
6580 GDB can now write to executable and core files (e.g. patch
6581 a variable's value). You must turn this switch on, specify
6582 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6583 by assigning a new value to a variable. Modifications take
6586 * Automatic SunOS shared library reading
6588 When you run your program, GDB automatically determines where its
6589 shared libraries (if any) have been loaded, and reads their symbols.
6590 The `share' command is no longer needed. This also works when
6591 examining core files.
6595 You can specify the number of lines that the `list' command shows.
6598 * New machines supported (host and target)
6600 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6601 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6602 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6604 * New hosts supported (not targets)
6606 IBM RT/PC: romp-ibm-aix or rtpc
6608 * New targets supported (not hosts)
6610 AMD 29000 embedded with COFF a29k-none-coff
6611 AMD 29000 embedded with a.out a29k-none-aout
6612 Ultracomputer remote kernel debug a29k-nyu-kern
6614 * New remote interfaces
6620 *** Changes in GDB-4.0:
6624 Wide output is wrapped at good places to make the output more readable.
6626 Gdb now supports cross-debugging from a host machine of one type to a
6627 target machine of another type. Communication with the target system
6628 is over serial lines. The ``target'' command handles connecting to the
6629 remote system; the ``load'' command will download a program into the
6630 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6631 also supports debugging of realtime processes running under VxWorks,
6632 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6633 stub on the target system.
6635 New CPUs supported include the AMD 29000 and Intel 960.
6637 GDB now reads object files and symbol tables via a ``binary file''
6638 library, which allows a single copy of GDB to debug programs of multiple
6639 object file types such as a.out and coff.
6641 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6642 refcard.dvi and refcard.ps are available to format it).
6645 * Control-Variable user interface simplified
6647 All variables that control the operation of the debugger can be set
6648 by the ``set'' command, and displayed by the ``show'' command.
6650 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6651 ``Show prompt'' produces the response:
6652 Gdb's prompt is new-gdb=>.
6654 What follows are the NEW set commands. The command ``help set'' will
6655 print a complete list of old and new set commands. ``help set FOO''
6656 will give a longer description of the variable FOO. ``show'' will show
6657 all of the variable descriptions and their current settings.
6659 confirm on/off: Enables warning questions for operations that are
6660 hard to recover from, e.g. rerunning the program while
6661 it is already running. Default is ON.
6663 editing on/off: Enables EMACS style command line editing
6664 of input. Previous lines can be recalled with
6665 control-P, the current line can be edited with control-B,
6666 you can search for commands with control-R, etc.
6669 history filename NAME: NAME is where the gdb command history
6670 will be stored. The default is .gdb_history,
6671 or the value of the environment variable
6674 history size N: The size, in commands, of the command history. The
6675 default is 256, or the value of the environment variable
6678 history save on/off: If this value is set to ON, the history file will
6679 be saved after exiting gdb. If set to OFF, the
6680 file will not be saved. The default is OFF.
6682 history expansion on/off: If this value is set to ON, then csh-like
6683 history expansion will be performed on
6684 command line input. The default is OFF.
6686 radix N: Sets the default radix for input and output. It can be set
6687 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6688 in the current radix, so "set radix 10" is always a no-op.
6690 height N: This integer value is the number of lines on a page. Default
6691 is 24, the current `stty rows'' setting, or the ``li#''
6692 setting from the termcap entry matching the environment
6695 width N: This integer value is the number of characters on a line.
6696 Default is 80, the current `stty cols'' setting, or the ``co#''
6697 setting from the termcap entry matching the environment
6700 Note: ``set screensize'' is obsolete. Use ``set height'' and
6701 ``set width'' instead.
6703 print address on/off: Print memory addresses in various command displays,
6704 such as stack traces and structure values. Gdb looks
6705 more ``symbolic'' if you turn this off; it looks more
6706 ``machine level'' with it on. Default is ON.
6708 print array on/off: Prettyprint arrays. New convenient format! Default
6711 print demangle on/off: Print C++ symbols in "source" form if on,
6714 print asm-demangle on/off: Same, for assembler level printouts
6717 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6720 * Support for Epoch Environment.
6722 The epoch environment is a version of Emacs v18 with windowing. One
6723 new command, ``inspect'', is identical to ``print'', except that if you
6724 are running in the epoch environment, the value is printed in its own
6728 * Support for Shared Libraries
6730 GDB can now debug programs and core files that use SunOS shared libraries.
6731 Symbols from a shared library cannot be referenced
6732 before the shared library has been linked with the program (this
6733 happens after you type ``run'' and before the function main() is entered).
6734 At any time after this linking (including when examining core files
6735 from dynamically linked programs), gdb reads the symbols from each
6736 shared library when you type the ``sharedlibrary'' command.
6737 It can be abbreviated ``share''.
6739 sharedlibrary REGEXP: Load shared object library symbols for files
6740 matching a unix regular expression. No argument
6741 indicates to load symbols for all shared libraries.
6743 info sharedlibrary: Status of loaded shared libraries.
6748 A watchpoint stops execution of a program whenever the value of an
6749 expression changes. Checking for this slows down execution
6750 tremendously whenever you are in the scope of the expression, but is
6751 quite useful for catching tough ``bit-spreader'' or pointer misuse
6752 problems. Some machines such as the 386 have hardware for doing this
6753 more quickly, and future versions of gdb will use this hardware.
6755 watch EXP: Set a watchpoint (breakpoint) for an expression.
6757 info watchpoints: Information about your watchpoints.
6759 delete N: Deletes watchpoint number N (same as breakpoints).
6760 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6761 enable N: Re-enables watchpoint number N (same as breakpoints).
6764 * C++ multiple inheritance
6766 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6769 * C++ exception handling
6771 Gdb now supports limited C++ exception handling. Besides the existing
6772 ability to breakpoint on an exception handler, gdb can breakpoint on
6773 the raising of an exception (before the stack is peeled back to the
6776 catch FOO: If there is a FOO exception handler in the dynamic scope,
6777 set a breakpoint to catch exceptions which may be raised there.
6778 Multiple exceptions (``catch foo bar baz'') may be caught.
6780 info catch: Lists all exceptions which may be caught in the
6781 current stack frame.
6784 * Minor command changes
6786 The command ``call func (arg, arg, ...)'' now acts like the print
6787 command, except it does not print or save a value if the function's result
6788 is void. This is similar to dbx usage.
6790 The ``up'' and ``down'' commands now always print the frame they end up
6791 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6792 frames without printing.
6794 * New directory command
6796 'dir' now adds directories to the FRONT of the source search path.
6797 The path starts off empty. Source files that contain debug information
6798 about the directory in which they were compiled can be found even
6799 with an empty path; Sun CC and GCC include this information. If GDB can't
6800 find your source file in the current directory, type "dir .".
6802 * Configuring GDB for compilation
6804 For normal use, type ``./configure host''. See README or gdb.texinfo
6807 GDB now handles cross debugging. If you are remotely debugging between
6808 two different machines, type ``./configure host -target=targ''.
6809 Host is the machine where GDB will run; targ is the machine
6810 where the program that you are debugging will run.