1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 8.0
6 * On Unix systems, GDB now supports transmitting environment variables
7 that are to be set or unset to GDBserver. These variables will
8 affect the environment to be passed to the remote inferior.
10 To inform GDB of environment variables that are to be transmitted to
11 GDBserver, use the "set environment" command. Only user set
12 environment variables are sent to GDBserver.
14 To inform GDB of environment variables that are to be unset before
15 the remote inferior is started by the GDBserver, use the "unset
18 * New features in the GDB remote stub, GDBserver
20 ** New "--selftest" command line option runs some GDBserver self
21 tests. These self tests are disabled in releases.
23 ** On Unix systems, GDBserver now does globbing expansion and variable
24 substitution in inferior command line arguments.
26 This is done by starting inferiors using a shell, like GDB does.
27 See "set startup-with-shell" in the user manual for how to disable
28 this from GDB when using "target extended-remote". When using
29 "target remote", you can disable the startup with shell by using the
30 new "--no-startup-with-shell" GDBserver command line option.
32 ** On Unix systems, GDBserver now supports receiving environment
33 variables that are to be set or unset from GDB. These variables
34 will affect the environment to be passed to the inferior.
38 QEnvironmentHexEncoded
39 Inform GDBserver of an environment variable that is to be passed to
40 the inferior when starting it.
43 Inform GDBserver of an environment variable that is to be unset
44 before starting the remote inferior.
47 Inform GDBserver that the environment should be reset (i.e.,
48 user-set environment variables should be unset).
51 Indicates whether the inferior must be started with a shell or not.
53 * The "maintenance print c-tdesc" command now takes an optional
54 argument which is the file name of XML target description.
59 Set and show compilation command used for compiling and injecting code
60 with the 'compile' commands.
62 set debug separate-debug-file
63 show debug separate-debug-file
64 Control the display of debug output about separate debug file search.
66 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
69 * Safer/improved support for debugging with no debug info
71 GDB no longer assumes functions with no debug information return
74 This means that GDB now refuses to call such functions unless you
75 tell it the function's type, by either casting the call to the
76 declared return type, or by casting the function to a function
77 pointer of the right type, and calling that:
79 (gdb) p getenv ("PATH")
80 'getenv' has unknown return type; cast the call to its declared return type
81 (gdb) p (char *) getenv ("PATH")
82 $1 = 0x7fffffffe "/usr/local/bin:/"...
83 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
84 $2 = 0x7fffffffe "/usr/local/bin:/"...
86 Similarly, GDB no longer assumes that global variables with no debug
87 info have type 'int', and refuses to print the variable's value
88 unless you tell it the variable's type:
91 'var' has unknown type; cast it to its declared type
95 * New native configurations
97 FreeBSD/aarch64 aarch64*-*-freebsd*
101 FreeBSD/aarch64 aarch64*-*-freebsd*
103 *** Changes in GDB 8.0
105 * GDB now supports access to the PKU register on GNU/Linux. The register is
106 added by the Memory Protection Keys for Userspace feature which will be
107 available in future Intel CPUs.
109 * GDB now supports C++11 rvalue references.
113 ** New functions to start, stop and access a running btrace recording.
114 ** Rvalue references are now supported in gdb.Type.
116 * GDB now supports recording and replaying rdrand and rdseed Intel 64
119 * Building GDB and GDBserver now requires a C++11 compiler.
121 For example, GCC 4.8 or later.
123 It is no longer possible to build GDB or GDBserver with a C
124 compiler. The --disable-build-with-cxx configure option has been
127 * Building GDB and GDBserver now requires GNU make >= 3.81.
129 It is no longer supported to build GDB or GDBserver with another
130 implementation of the make program or an earlier version of GNU make.
132 * Native debugging on MS-Windows supports command-line redirection
134 Command-line arguments used for starting programs on MS-Windows can
135 now include redirection symbols supported by native Windows shells,
136 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
137 as "run", "start", and "set args", as well as the corresponding MI
140 * Support for thread names on MS-Windows.
142 GDB now catches and handles the special exception that programs
143 running on MS-Windows use to assign names to threads in the
146 * Support for Java programs compiled with gcj has been removed.
148 * User commands now accept an unlimited number of arguments.
149 Previously, only up to 10 was accepted.
151 * The "eval" command now expands user-defined command arguments.
153 This makes it easier to process a variable number of arguments:
158 eval "print $arg%d", $i
163 * Target descriptions can now describe registers for sparc32 and sparc64.
165 * GDB now supports DWARF version 5 (debug information format).
166 Its .debug_names index is not yet supported.
168 * New native configurations
170 FreeBSD/mips mips*-*-freebsd
174 Synopsys ARC arc*-*-elf32
175 FreeBSD/mips mips*-*-freebsd
177 * Removed targets and native configurations
179 Alpha running FreeBSD alpha*-*-freebsd*
180 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
185 Erases all the flash memory regions reported by the target.
187 maint print arc arc-instruction address
188 Print internal disassembler information about instruction at a given address.
192 set disassembler-options
193 show disassembler-options
194 Controls the passing of target specific information to the disassembler.
195 If it is necessary to specify more than one disassembler option then
196 multiple options can be placed together into a comma separated list.
197 The default value is the empty string. Currently, the only supported
198 targets are ARM, PowerPC and S/390.
203 Erases all the flash memory regions reported by the target. This is
204 equivalent to the CLI command flash-erase.
206 -file-list-shared-libraries
207 List the shared libraries in the program. This is
208 equivalent to the CLI command "info shared".
210 *** Changes in GDB 7.12
212 * GDB and GDBserver now build with a C++ compiler by default.
214 The --enable-build-with-cxx configure option is now enabled by
215 default. One must now explicitly configure with
216 --disable-build-with-cxx in order to build with a C compiler. This
217 option will be removed in a future release.
219 * GDBserver now supports recording btrace without maintaining an active
222 * GDB now supports a negative repeat count in the 'x' command to examine
223 memory backward from the given address. For example:
226 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
227 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
228 (gdb) x/-5i 0x0000000000400580
229 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
230 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
231 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
232 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
233 0x40057b <main(int, char**)+25>:
234 callq 0x400536 <Func1(int, char const*)>
236 * Fortran: Support structures with fields of dynamic types and
237 arrays of dynamic types.
239 * The symbol dumping maintenance commands have new syntax.
240 maint print symbols [-pc address] [--] [filename]
241 maint print symbols [-objfile objfile] [-source source] [--] [filename]
242 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
243 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
244 maint print msymbols [-objfile objfile] [--] [filename]
246 * GDB now supports multibit bitfields and enums in target register
249 * New Python-based convenience function $_as_string(val), which returns
250 the textual representation of a value. This function is especially
251 useful to obtain the text label of an enum value.
253 * Intel MPX bound violation handling.
255 Segmentation faults caused by a Intel MPX boundary violation
256 now display the kind of violation (upper or lower), the memory
257 address accessed and the memory bounds, along with the usual
258 signal received and code location.
262 Program received signal SIGSEGV, Segmentation fault
263 Upper bound violation while accessing address 0x7fffffffc3b3
264 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
265 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
267 * Rust language support.
268 GDB now supports debugging programs written in the Rust programming
269 language. See https://www.rust-lang.org/ for more information about
272 * Support for running interpreters on specified input/output devices
274 GDB now supports a new mechanism that allows frontends to provide
275 fully featured GDB console views, as a better alternative to
276 building such views on top of the "-interpreter-exec console"
277 command. See the new "new-ui" command below. With that command,
278 frontends can now start GDB in the traditional command-line mode
279 running in an embedded terminal emulator widget, and create a
280 separate MI interpreter running on a specified i/o device. In this
281 way, GDB handles line editing, history, tab completion, etc. in the
282 console all by itself, and the GUI uses the separate MI interpreter
283 for its own control and synchronization, invisible to the command
286 * The "catch syscall" command catches groups of related syscalls.
288 The "catch syscall" command now supports catching a group of related
289 syscalls using the 'group:' or 'g:' prefix.
294 skip -gfile file-glob-pattern
295 skip -function function
296 skip -rfunction regular-expression
297 A generalized form of the skip command, with new support for
298 glob-style file names and regular expressions for function names.
299 Additionally, a file spec and a function spec may now be combined.
301 maint info line-table REGEXP
302 Display the contents of GDB's internal line table data struture.
305 Run any GDB unit tests that were compiled in.
308 Start a new user interface instance running INTERP as interpreter,
309 using the TTY file for input/output.
313 ** gdb.Breakpoint objects have a new attribute "pending", which
314 indicates whether the breakpoint is pending.
315 ** Three new breakpoint-related events have been added:
316 gdb.breakpoint_created, gdb.breakpoint_modified, and
317 gdb.breakpoint_deleted.
320 Signal ("set") the given MS-Windows event object. This is used in
321 conjunction with the Windows JIT debugging (AeDebug) support, where
322 the OS suspends a crashing process until a debugger can attach to
323 it. Resuming the crashing process, in order to debug it, is done by
326 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
327 was added in GDBserver, including JIT compiling fast tracepoint's
328 conditional expression bytecode into native code.
330 * Support for various remote target protocols and ROM monitors has
333 target m32rsdi Remote M32R debugging over SDI
334 target mips MIPS remote debugging protocol
335 target pmon PMON ROM monitor
336 target ddb NEC's DDB variant of PMON for Vr4300
337 target rockhopper NEC RockHopper variant of PMON
338 target lsi LSI variant of PMO
340 * Support for tracepoints and fast tracepoints on powerpc-linux,
341 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
342 including JIT compiling fast tracepoint's conditional expression
343 bytecode into native code.
345 * MI async record =record-started now includes the method and format used for
346 recording. For example:
348 =record-started,thread-group="i1",method="btrace",format="bts"
350 * MI async record =thread-selected now includes the frame field. For example:
352 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
356 Andes NDS32 nds32*-*-elf
358 *** Changes in GDB 7.11
360 * GDB now supports debugging kernel-based threads on FreeBSD.
362 * Per-inferior thread numbers
364 Thread numbers are now per inferior instead of global. If you're
365 debugging multiple inferiors, GDB displays thread IDs using a
366 qualified INF_NUM.THR_NUM form. For example:
370 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
371 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
372 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
373 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
375 As consequence, thread numbers as visible in the $_thread
376 convenience variable and in Python's InferiorThread.num attribute
377 are no longer unique between inferiors.
379 GDB now maintains a second thread ID per thread, referred to as the
380 global thread ID, which is the new equivalent of thread numbers in
381 previous releases. See also $_gthread below.
383 For backwards compatibility, MI's thread IDs always refer to global
386 * Commands that accept thread IDs now accept the qualified
387 INF_NUM.THR_NUM form as well. For example:
390 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
393 * In commands that accept a list of thread IDs, you can now refer to
394 all threads of an inferior using a star wildcard. GDB accepts
395 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
396 refer to all threads of the current inferior. For example, "info
399 * You can use "info threads -gid" to display the global thread ID of
402 * The new convenience variable $_gthread holds the global number of
405 * The new convenience variable $_inferior holds the number of the
408 * GDB now displays the ID and name of the thread that hit a breakpoint
409 or received a signal, if your program is multi-threaded. For
412 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
413 Thread 1 "main" received signal SIGINT, Interrupt.
415 * Record btrace now supports non-stop mode.
417 * Support for tracepoints on aarch64-linux was added in GDBserver.
419 * The 'record instruction-history' command now indicates speculative execution
420 when using the Intel Processor Trace recording format.
422 * GDB now allows users to specify explicit locations, bypassing
423 the linespec parser. This feature is also available to GDB/MI
426 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
427 GDB now is able to debug both AArch64 applications and ARM applications
430 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
431 including JIT compiling fast tracepoint's conditional expression bytecode
434 * GDB now supports displaced stepping on AArch64 GNU/Linux.
436 * "info threads", "info inferiors", "info display", "info checkpoints"
437 and "maint info program-spaces" now list the corresponding items in
438 ascending ID order, for consistency with all other "info" commands.
440 * In Ada, the overloads selection menu has been enhanced to display the
441 parameter types and the return types for the matching overloaded subprograms.
445 maint set target-non-stop (on|off|auto)
446 maint show target-non-stop
447 Control whether GDB targets always operate in non-stop mode even if
448 "set non-stop" is "off". The default is "auto", meaning non-stop
449 mode is enabled if supported by the target.
451 maint set bfd-sharing
452 maint show bfd-sharing
453 Control the reuse of bfd objects.
457 Control display of debugging info regarding bfd caching.
461 Control display of debugging info regarding FreeBSD threads.
463 set remote multiprocess-extensions-packet
464 show remote multiprocess-extensions-packet
465 Set/show the use of the remote protocol multiprocess extensions.
467 set remote thread-events
468 show remote thread-events
469 Set/show the use of thread create/exit events.
471 set ada print-signatures on|off
472 show ada print-signatures"
473 Control whether parameter types and return types are displayed in overloads
474 selection menus. It is activaled (@code{on}) by default.
478 Controls the maximum size of memory, in bytes, that GDB will
479 allocate for value contents. Prevents incorrect programs from
480 causing GDB to allocate overly large buffers. Default is 64k.
482 * The "disassemble" command accepts a new modifier: /s.
483 It prints mixed source+disassembly like /m with two differences:
484 - disassembled instructions are now printed in program order, and
485 - and source for all relevant files is now printed.
486 The "/m" option is now considered deprecated: its "source-centric"
487 output hasn't proved useful in practice.
489 * The "record instruction-history" command accepts a new modifier: /s.
490 It behaves exactly like /m and prints mixed source+disassembly.
492 * The "set scheduler-locking" command supports a new mode "replay".
493 It behaves like "off" in record mode and like "on" in replay mode.
495 * Support for various ROM monitors has been removed:
497 target dbug dBUG ROM monitor for Motorola ColdFire
498 target picobug Motorola picobug monitor
499 target dink32 DINK32 ROM monitor for PowerPC
500 target m32r Renesas M32R/D ROM monitor
501 target mon2000 mon2000 ROM monitor
502 target ppcbug PPCBUG ROM monitor for PowerPC
504 * Support for reading/writing memory and extracting values on architectures
505 whose memory is addressable in units of any integral multiple of 8 bits.
510 Indicates whether the inferior must be started with a shell or not.
513 Indicates that an exec system call was executed.
515 exec-events feature in qSupported
516 The qSupported packet allows GDB to request support for exec
517 events using the new 'gdbfeature' exec-event, and the qSupported
518 response can contain the corresponding 'stubfeature'. Set and
519 show commands can be used to display whether these features are enabled.
522 Equivalent to interrupting with the ^C character, but works in
525 thread created stop reason (T05 create:...)
526 Indicates that the thread was just created and is stopped at entry.
528 thread exit stop reply (w exitcode;tid)
529 Indicates that the thread has terminated.
532 Enables/disables thread create and exit event reporting. For
533 example, this is used in non-stop mode when GDB stops a set of
534 threads and synchronously waits for the their corresponding stop
535 replies. Without exit events, if one of the threads exits, GDB
536 would hang forever not knowing that it should no longer expect a
537 stop for that same thread.
540 Indicates that there are no resumed threads left in the target (all
541 threads are stopped). The remote stub reports support for this stop
542 reply to GDB's qSupported query.
545 Enables/disables catching syscalls from the inferior process.
546 The remote stub reports support for this packet to GDB's qSupported query.
548 syscall_entry stop reason
549 Indicates that a syscall was just called.
551 syscall_return stop reason
552 Indicates that a syscall just returned.
554 * Extended-remote exec events
556 ** GDB now has support for exec events on extended-remote Linux targets.
557 For such targets with Linux kernels 2.5.46 and later, this enables
558 follow-exec-mode and exec catchpoints.
560 set remote exec-event-feature-packet
561 show remote exec-event-feature-packet
562 Set/show the use of the remote exec event feature.
564 * Thread names in remote protocol
566 The reply to qXfer:threads:read may now include a name attribute for each
569 * Target remote mode fork and exec events
571 ** GDB now has support for fork and exec events on target remote mode
572 Linux targets. For such targets with Linux kernels 2.5.46 and later,
573 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
574 fork and exec catchpoints.
576 * Remote syscall events
578 ** GDB now has support for catch syscall on remote Linux targets,
579 currently enabled on x86/x86_64 architectures.
581 set remote catch-syscall-packet
582 show remote catch-syscall-packet
583 Set/show the use of the remote catch syscall feature.
587 ** The -var-set-format command now accepts the zero-hexadecimal
588 format. It outputs data in hexadecimal format with zero-padding on the
593 ** gdb.InferiorThread objects have a new attribute "global_num",
594 which refers to the thread's global thread ID. The existing
595 "num" attribute now refers to the thread's per-inferior number.
596 See "Per-inferior thread numbers" above.
597 ** gdb.InferiorThread objects have a new attribute "inferior", which
598 is the Inferior object the thread belongs to.
600 *** Changes in GDB 7.10
602 * Support for process record-replay and reverse debugging on aarch64*-linux*
603 targets has been added. GDB now supports recording of A64 instruction set
604 including advance SIMD instructions.
606 * Support for Sun's version of the "stabs" debug file format has been removed.
608 * GDB now honors the content of the file /proc/PID/coredump_filter
609 (PID is the process ID) on GNU/Linux systems. This file can be used
610 to specify the types of memory mappings that will be included in a
611 corefile. For more information, please refer to the manual page of
612 "core(5)". GDB also has a new command: "set use-coredump-filter
613 on|off". It allows to set whether GDB will read the content of the
614 /proc/PID/coredump_filter file when generating a corefile.
616 * The "info os" command on GNU/Linux can now display information on
618 "info os cpus" Listing of all cpus/cores on the system
620 * GDB has two new commands: "set serial parity odd|even|none" and
621 "show serial parity". These allows to set or show parity for the
624 * The "info source" command now displays the producer string if it was
625 present in the debug info. This typically includes the compiler version
626 and may include things like its command line arguments.
628 * The "info dll", an alias of the "info sharedlibrary" command,
629 is now available on all platforms.
631 * Directory names supplied to the "set sysroot" commands may be
632 prefixed with "target:" to tell GDB to access shared libraries from
633 the target system, be it local or remote. This replaces the prefix
634 "remote:". The default sysroot has been changed from "" to
635 "target:". "remote:" is automatically converted to "target:" for
636 backward compatibility.
638 * The system root specified by "set sysroot" will be prepended to the
639 filename of the main executable (if reported to GDB as absolute by
640 the operating system) when starting processes remotely, and when
641 attaching to already-running local or remote processes.
643 * GDB now supports automatic location and retrieval of executable
644 files from remote targets. Remote debugging can now be initiated
645 using only a "target remote" or "target extended-remote" command
646 (no "set sysroot" or "file" commands are required). See "New remote
649 * The "dump" command now supports verilog hex format.
651 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
653 * On GNU/Linux, GDB and gdbserver are now able to access executable
654 and shared library files without a "set sysroot" command when
655 attaching to processes running in different mount namespaces from
656 the debugger. This makes it possible to attach to processes in
657 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
658 See "New remote packets" below.
660 * The "tui reg" command now provides completion for all of the
661 available register groups, including target specific groups.
663 * The HISTSIZE environment variable is no longer read when determining
664 the size of GDB's command history. GDB now instead reads the dedicated
665 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
666 disables truncation of command history. Non-numeric values of GDBHISTSIZE
671 ** Memory ports can now be unbuffered.
675 ** gdb.Objfile objects have a new attribute "username",
676 which is the name of the objfile as specified by the user,
677 without, for example, resolving symlinks.
678 ** You can now write frame unwinders in Python.
679 ** gdb.Type objects have a new method "optimized_out",
680 returning optimized out gdb.Value instance of this type.
681 ** gdb.Value objects have new methods "reference_value" and
682 "const_value" which return a reference to the value and a
683 "const" version of the value respectively.
687 maint print symbol-cache
688 Print the contents of the symbol cache.
690 maint print symbol-cache-statistics
691 Print statistics of symbol cache usage.
693 maint flush-symbol-cache
694 Flush the contents of the symbol cache.
698 Start branch trace recording using Branch Trace Store (BTS) format.
701 Evaluate expression by using the compiler and print result.
705 Explicit commands for enabling and disabling tui mode.
708 set mpx bound on i386 and amd64
709 Support for bound table investigation on Intel MPX enabled applications.
713 Start branch trace recording using Intel Processor Trace format.
716 Print information about branch tracing internals.
718 maint btrace packet-history
719 Print the raw branch tracing data.
721 maint btrace clear-packet-history
722 Discard the stored raw branch tracing data.
725 Discard all branch tracing data. It will be fetched and processed
726 anew by the next "record" command.
731 Renamed from "set debug dwarf2-die".
733 Renamed from "show debug dwarf2-die".
736 Renamed from "set debug dwarf2-read".
737 show debug dwarf-read
738 Renamed from "show debug dwarf2-read".
740 maint set dwarf always-disassemble
741 Renamed from "maint set dwarf2 always-disassemble".
742 maint show dwarf always-disassemble
743 Renamed from "maint show dwarf2 always-disassemble".
745 maint set dwarf max-cache-age
746 Renamed from "maint set dwarf2 max-cache-age".
747 maint show dwarf max-cache-age
748 Renamed from "maint show dwarf2 max-cache-age".
751 show debug dwarf-line
752 Control display of debugging info regarding DWARF line processing.
756 Set the maximum number of candidates to be considered during
757 completion. The default value is 200. This limit allows GDB
758 to avoid generating large completion lists, the computation of
759 which can cause the debugger to become temporarily unresponsive.
761 set history remove-duplicates
762 show history remove-duplicates
763 Control the removal of duplicate history entries.
765 maint set symbol-cache-size
766 maint show symbol-cache-size
767 Control the size of the symbol cache.
769 set|show record btrace bts buffer-size
770 Set and show the size of the ring buffer used for branch tracing in
772 The obtained size may differ from the requested size. Use "info
773 record" to see the obtained buffer size.
775 set debug linux-namespaces
776 show debug linux-namespaces
777 Control display of debugging info regarding Linux namespaces.
779 set|show record btrace pt buffer-size
780 Set and show the size of the ring buffer used for branch tracing in
781 Intel Processor Trace format.
782 The obtained size may differ from the requested size. Use "info
783 record" to see the obtained buffer size.
785 maint set|show btrace pt skip-pad
786 Set and show whether PAD packets are skipped when computing the
789 * The command 'thread apply all' can now support new option '-ascending'
790 to call its specified command for all threads in ascending order.
792 * Python/Guile scripting
794 ** GDB now supports auto-loading of Python/Guile scripts contained in the
795 special section named `.debug_gdb_scripts'.
799 qXfer:btrace-conf:read
800 Return the branch trace configuration for the current thread.
802 Qbtrace-conf:bts:size
803 Set the requested ring buffer size for branch tracing in BTS format.
806 Enable Intel Procesor Trace-based branch tracing for the current
807 process. The remote stub reports support for this packet to GDB's
811 Set the requested ring buffer size for branch tracing in Intel Processor
815 Indicates a memory breakpoint instruction was executed, irrespective
816 of whether it was GDB that planted the breakpoint or the breakpoint
817 is hardcoded in the program. This is required for correct non-stop
821 Indicates the target stopped for a hardware breakpoint. This is
822 required for correct non-stop mode operation.
825 Return information about files on the remote system.
828 Return the full absolute name of the file that was executed to
829 create a process running on the remote system.
832 Select the filesystem on which vFile: operations with filename
833 arguments will operate. This is required for GDB to be able to
834 access files on remote targets where the remote stub does not
835 share a common filesystem with the inferior(s).
838 Indicates that a fork system call was executed.
841 Indicates that a vfork system call was executed.
843 vforkdone stop reason
844 Indicates that a vfork child of the specified process has executed
845 an exec or exit, allowing the vfork parent to resume execution.
847 fork-events and vfork-events features in qSupported
848 The qSupported packet allows GDB to request support for fork and
849 vfork events using new 'gdbfeatures' fork-events and vfork-events,
850 and the qSupported response can contain the corresponding
851 'stubfeatures'. Set and show commands can be used to display
852 whether these features are enabled.
854 * Extended-remote fork events
856 ** GDB now has support for fork events on extended-remote Linux
857 targets. For targets with Linux kernels 2.5.60 and later, this
858 enables follow-fork-mode and detach-on-fork for both fork and
859 vfork, as well as fork and vfork catchpoints.
861 * The info record command now shows the recording format and the
862 branch tracing configuration for the current thread when using
863 the btrace record target.
864 For the BTS format, it shows the ring buffer size.
866 * GDB now has support for DTrace USDT (Userland Static Defined
867 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
869 * GDB now supports access to vector registers on S/390 GNU/Linux
872 * Removed command line options
874 -xdb HP-UX XDB compatibility mode.
876 * Removed targets and native configurations
878 HP/PA running HP-UX hppa*-*-hpux*
879 Itanium running HP-UX ia64-*-hpux*
881 * New configure options
884 This configure option allows the user to build GDB with support for
885 Intel Processor Trace (default: auto). This requires libipt.
887 --with-libipt-prefix=PATH
888 Specify the path to the version of libipt that GDB should use.
889 $PATH/include should contain the intel-pt.h header and
890 $PATH/lib should contain the libipt.so library.
892 *** Changes in GDB 7.9.1
896 ** Xmethods can now specify a result type.
898 *** Changes in GDB 7.9
900 * GDB now supports hardware watchpoints on x86 GNU Hurd.
904 ** You can now access frame registers from Python scripts.
905 ** New attribute 'producer' for gdb.Symtab objects.
906 ** gdb.Objfile objects have a new attribute "progspace",
907 which is the gdb.Progspace object of the containing program space.
908 ** gdb.Objfile objects have a new attribute "owner".
909 ** gdb.Objfile objects have a new attribute "build_id",
910 which is the build ID generated when the file was built.
911 ** gdb.Objfile objects have a new method "add_separate_debug_file".
912 ** A new event "gdb.clear_objfiles" has been added, triggered when
913 selecting a new file to debug.
914 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
915 ** New function gdb.lookup_objfile.
917 New events which are triggered when GDB modifies the state of the
920 ** gdb.events.inferior_call_pre: Function call is about to be made.
921 ** gdb.events.inferior_call_post: Function call has just been made.
922 ** gdb.events.memory_changed: A memory location has been altered.
923 ** gdb.events.register_changed: A register has been altered.
925 * New Python-based convenience functions:
927 ** $_caller_is(name [, number_of_frames])
928 ** $_caller_matches(regexp [, number_of_frames])
929 ** $_any_caller_is(name [, number_of_frames])
930 ** $_any_caller_matches(regexp [, number_of_frames])
932 * GDB now supports the compilation and injection of source code into
933 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
934 to compile the source code to object code, and if successful, inject
935 and execute that code within the current context of the inferior.
936 Currently the C language is supported. The commands used to
937 interface with this new feature are:
939 compile code [-raw|-r] [--] [source code]
940 compile file [-raw|-r] filename
944 demangle [-l language] [--] name
945 Demangle "name" in the specified language, or the current language
946 if elided. This command is renamed from the "maint demangle" command.
947 The latter is kept as a no-op to avoid "maint demangle" being interpreted
948 as "maint demangler-warning".
950 queue-signal signal-name-or-number
951 Queue a signal to be delivered to the thread when it is resumed.
953 add-auto-load-scripts-directory directory
954 Add entries to the list of directories from which to load auto-loaded
957 maint print user-registers
958 List all currently available "user" registers.
960 compile code [-r|-raw] [--] [source code]
961 Compile, inject, and execute in the inferior the executable object
962 code produced by compiling the provided source code.
964 compile file [-r|-raw] filename
965 Compile and inject into the inferior the executable object code
966 produced by compiling the source code stored in the filename
969 * On resume, GDB now always passes the signal the program had stopped
970 for to the thread the signal was sent to, even if the user changed
971 threads before resuming. Previously GDB would often (but not
972 always) deliver the signal to the thread that happens to be current
975 * Conversely, the "signal" command now consistently delivers the
976 requested signal to the current thread. GDB now asks for
977 confirmation if the program had stopped for a signal and the user
978 switched threads meanwhile.
980 * "breakpoint always-inserted" modes "off" and "auto" merged.
982 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
983 won't remove breakpoints from the target until all threads stop,
984 even in non-stop mode. The "auto" mode has been removed, and "off"
985 is now the default mode.
989 set debug symbol-lookup
990 show debug symbol-lookup
991 Control display of debugging info regarding symbol lookup.
995 ** The -list-thread-groups command outputs an exit-code field for
996 inferiors that have exited.
1000 MIPS SDE mips*-sde*-elf*
1004 Support for these obsolete configurations has been removed.
1006 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
1007 SGI Irix-5.x mips-*-irix5*
1008 SGI Irix-6.x mips-*-irix6*
1009 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
1010 VAX running Ultrix vax-*-ultrix*
1012 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1013 and "assf"), have been removed. Use the "sharedlibrary" command, or
1014 its alias "share", instead.
1016 *** Changes in GDB 7.8
1018 * New command line options
1021 This is an alias for the --data-directory option.
1023 * GDB supports printing and modifying of variable length automatic arrays
1024 as specified in ISO C99.
1026 * The ARM simulator now supports instruction level tracing
1027 with or without disassembly.
1031 GDB now has support for scripting using Guile. Whether this is
1032 available is determined at configure time.
1033 Guile version 2.0 or greater is required.
1034 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
1036 * New commands (for set/show, see "New options" below)
1040 Invoke CODE by passing it to the Guile interpreter.
1044 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
1046 info auto-load guile-scripts [regexp]
1047 Print the list of automatically loaded Guile scripts.
1049 * The source command is now capable of sourcing Guile scripts.
1050 This feature is dependent on the debugger being built with Guile support.
1054 set print symbol-loading (off|brief|full)
1055 show print symbol-loading
1056 Control whether to print informational messages when loading symbol
1057 information for a file. The default is "full", but when debugging
1058 programs with large numbers of shared libraries the amount of output
1059 becomes less useful.
1061 set guile print-stack (none|message|full)
1062 show guile print-stack
1063 Show a stack trace when an error is encountered in a Guile script.
1065 set auto-load guile-scripts (on|off)
1066 show auto-load guile-scripts
1067 Control auto-loading of Guile script files.
1069 maint ada set ignore-descriptive-types (on|off)
1070 maint ada show ignore-descriptive-types
1071 Control whether the debugger should ignore descriptive types in Ada
1072 programs. The default is not to ignore the descriptive types. See
1073 the user manual for more details on descriptive types and the intended
1074 usage of this option.
1076 set auto-connect-native-target
1078 Control whether GDB is allowed to automatically connect to the
1079 native target for the run, attach, etc. commands when not connected
1080 to any target yet. See also "target native" below.
1082 set record btrace replay-memory-access (read-only|read-write)
1083 show record btrace replay-memory-access
1084 Control what memory accesses are allowed during replay.
1086 maint set target-async (on|off)
1087 maint show target-async
1088 This controls whether GDB targets operate in synchronous or
1089 asynchronous mode. Normally the default is asynchronous, if it is
1090 available; but this can be changed to more easily debug problems
1091 occurring only in synchronous mode.
1093 set mi-async (on|off)
1095 Control whether MI asynchronous mode is preferred. This supersedes
1096 "set target-async" of previous GDB versions.
1098 * "set target-async" is deprecated as a CLI option and is now an alias
1099 for "set mi-async" (only puts MI into async mode).
1101 * Background execution commands (e.g., "c&", "s&", etc.) are now
1102 possible ``out of the box'' if the target supports them. Previously
1103 the user would need to explicitly enable the possibility with the
1104 "set target-async on" command.
1106 * New features in the GDB remote stub, GDBserver
1108 ** New option --debug-format=option1[,option2,...] allows one to add
1109 additional text to each output. At present only timestamps
1110 are supported: --debug-format=timestamps.
1111 Timestamps can also be turned on with the
1112 "monitor set debug-format timestamps" command from GDB.
1114 * The 'record instruction-history' command now starts counting instructions
1115 at one. This also affects the instruction ranges reported by the
1116 'record function-call-history' command when given the /i modifier.
1118 * The command 'record function-call-history' supports a new modifier '/c' to
1119 indent the function names based on their call stack depth.
1120 The fields for the '/i' and '/l' modifier have been reordered.
1121 The source line range is now prefixed with 'at'.
1122 The instruction range is now prefixed with 'inst'.
1123 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1124 "record instruction-history" and "list" commands.
1126 * The ranges given as arguments to the 'record function-call-history' and
1127 'record instruction-history' commands are now inclusive.
1129 * The btrace record target now supports the 'record goto' command.
1130 For locations inside the execution trace, the back trace is computed
1131 based on the information stored in the execution trace.
1133 * The btrace record target supports limited reverse execution and replay.
1134 The target does not record data and therefore does not allow reading
1135 memory or registers.
1137 * The "catch syscall" command now works on s390*-linux* targets.
1139 * The "compare-sections" command is no longer specific to target
1140 remote. It now works with all targets.
1142 * All native targets are now consistently called "native".
1143 Consequently, the "target child", "target GNU", "target djgpp",
1144 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1145 commands have been replaced with "target native". The QNX/NTO port
1146 leaves the "procfs" target in place and adds a "native" target for
1147 consistency with other ports. The impact on users should be minimal
1148 as these commands previously either throwed an error, or were
1149 no-ops. The target's name is visible in the output of the following
1150 commands: "help target", "info target", "info files", "maint print
1153 * The "target native" command now connects to the native target. This
1154 can be used to launch native programs even when "set
1155 auto-connect-native-target" is set to off.
1157 * GDB now supports access to Intel MPX registers on GNU/Linux.
1159 * Support for Intel AVX-512 registers on GNU/Linux.
1160 Support displaying and modifying Intel AVX-512 registers
1161 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1163 * New remote packets
1165 qXfer:btrace:read's annex
1166 The qXfer:btrace:read packet supports a new annex 'delta' to read
1167 branch trace incrementally.
1171 ** Valid Python operations on gdb.Value objects representing
1172 structs/classes invoke the corresponding overloaded operators if
1174 ** New `Xmethods' feature in the Python API. Xmethods are
1175 additional methods or replacements for existing methods of a C++
1176 class. This feature is useful for those cases where a method
1177 defined in C++ source code could be inlined or optimized out by
1178 the compiler, making it unavailable to GDB.
1181 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1183 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1184 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1185 its alias "share", instead.
1187 * The commands "set remotebaud" and "show remotebaud" are no longer
1188 supported. Use "set serial baud" and "show serial baud" (respectively)
1193 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1194 target-async". The latter is left as a deprecated alias of the
1195 former for backward compatibility. If the target supports it,
1196 CLI background execution commands are now always possible by
1197 default, independently of whether the frontend stated a
1198 preference for asynchronous execution with "-gdb-set mi-async".
1199 Previously "-gdb-set target-async off" affected both MI execution
1200 commands and CLI execution commands.
1202 *** Changes in GDB 7.7
1204 * Improved support for process record-replay and reverse debugging on
1205 arm*-linux* targets. Support for thumb32 and syscall instruction
1206 recording has been added.
1208 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1210 * GDB now supports Fission DWP file format version 2.
1211 http://gcc.gnu.org/wiki/DebugFission
1213 * New convenience function "$_isvoid", to check whether an expression
1214 is void. A void expression is an expression where the type of the
1215 result is "void". For example, some convenience variables may be
1216 "void" when evaluated (e.g., "$_exitcode" before the execution of
1217 the program being debugged; or an undefined convenience variable).
1218 Another example, when calling a function whose return type is
1221 * The "maintenance print objfiles" command now takes an optional regexp.
1223 * The "catch syscall" command now works on arm*-linux* targets.
1225 * GDB now consistently shows "<not saved>" when printing values of
1226 registers the debug info indicates have not been saved in the frame
1227 and there's nowhere to retrieve them from
1228 (callee-saved/call-clobbered registers):
1233 (gdb) info registers rax
1236 Before, the former would print "<optimized out>", and the latter
1237 "*value not available*".
1239 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1244 ** Frame filters and frame decorators have been added.
1245 ** Temporary breakpoints are now supported.
1246 ** Line tables representation has been added.
1247 ** New attribute 'parent_type' for gdb.Field objects.
1248 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1249 ** New attribute 'name' for gdb.Type objects.
1253 Nios II ELF nios2*-*-elf
1254 Nios II GNU/Linux nios2*-*-linux
1255 Texas Instruments MSP430 msp430*-*-elf
1257 * Removed native configurations
1259 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1260 been removed. ELF variants of these configurations are kept supported.
1262 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1263 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1264 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1265 i[34567]86-*-openbsd3.[0-3]
1266 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1267 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1268 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1272 Like "catch throw", but catches a re-thrown exception.
1273 maint check-psymtabs
1274 Renamed from old "maint check-symtabs".
1276 Perform consistency checks on symtabs.
1277 maint expand-symtabs
1278 Expand symtabs matching an optional regexp.
1281 Display the details of GDB configure-time options.
1283 maint set|show per-command
1284 maint set|show per-command space
1285 maint set|show per-command time
1286 maint set|show per-command symtab
1287 Enable display of per-command gdb resource usage.
1289 remove-symbol-file FILENAME
1290 remove-symbol-file -a ADDRESS
1291 Remove a symbol file added via add-symbol-file. The file to remove
1292 can be identified by its filename or by an address that lies within
1293 the boundaries of this symbol file in memory.
1296 info exceptions REGEXP
1297 Display the list of Ada exceptions defined in the program being
1298 debugged. If provided, only the exceptions whose names match REGEXP
1303 set debug symfile off|on
1305 Control display of debugging info regarding reading symbol files and
1306 symbol tables within those files
1308 set print raw frame-arguments
1309 show print raw frame-arguments
1310 Set/show whether to print frame arguments in raw mode,
1311 disregarding any defined pretty-printers.
1313 set remote trace-status-packet
1314 show remote trace-status-packet
1315 Set/show the use of remote protocol qTStatus packet.
1319 Control display of debugging messages related to Nios II targets.
1323 Control whether target-assisted range stepping is enabled.
1325 set startup-with-shell
1326 show startup-with-shell
1327 Specifies whether Unix child processes are started via a shell or
1332 Use the target memory cache for accesses to the code segment. This
1333 improves performance of remote debugging (particularly disassembly).
1335 * You can now use a literal value 'unlimited' for options that
1336 interpret 0 or -1 as meaning "unlimited". E.g., "set
1337 trace-buffer-size unlimited" is now an alias for "set
1338 trace-buffer-size -1" and "set height unlimited" is now an alias for
1341 * The "set debug symtab-create" debugging option of GDB has been changed to
1342 accept a verbosity level. 0 means "off", 1 provides basic debugging
1343 output, and values of 2 or greater provides more verbose output.
1345 * New command-line options
1347 Display the details of GDB configure-time options.
1349 * The command 'tsave' can now support new option '-ctf' to save trace
1350 buffer in Common Trace Format.
1352 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1355 * GDB now implements the the C++ 'typeid' operator.
1357 * The new convenience variable $_exception holds the exception being
1358 thrown or caught at an exception-related catchpoint.
1360 * The exception-related catchpoints, like "catch throw", now accept a
1361 regular expression which can be used to filter exceptions by type.
1363 * The new convenience variable $_exitsignal is automatically set to
1364 the terminating signal number when the program being debugged dies
1365 due to an uncaught signal.
1369 ** All MI commands now accept an optional "--language" option.
1370 Support for this feature can be verified by using the "-list-features"
1371 command, which should contain "language-option".
1373 ** The new command -info-gdb-mi-command allows the user to determine
1374 whether a GDB/MI command is supported or not.
1376 ** The "^error" result record returned when trying to execute an undefined
1377 GDB/MI command now provides a variable named "code" whose content is the
1378 "undefined-command" error code. Support for this feature can be verified
1379 by using the "-list-features" command, which should contain
1380 "undefined-command-error-code".
1382 ** The -trace-save MI command can optionally save trace buffer in Common
1385 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1387 ** The command -data-list-register-values now accepts an optional
1388 "--skip-unavailable" option. When used, only the available registers
1391 ** The new command -trace-frame-collected dumps collected variables,
1392 computed expressions, tvars, memory and registers in a traceframe.
1394 ** The commands -stack-list-locals, -stack-list-arguments and
1395 -stack-list-variables now accept an option "--skip-unavailable".
1396 When used, only the available locals or arguments are displayed.
1398 ** The -exec-run command now accepts an optional "--start" option.
1399 When used, the command follows the same semantics as the "start"
1400 command, stopping the program's execution at the start of its
1401 main subprogram. Support for this feature can be verified using
1402 the "-list-features" command, which should contain
1403 "exec-run-start-option".
1405 ** The new commands -catch-assert and -catch-exceptions insert
1406 catchpoints stopping the program when Ada exceptions are raised.
1408 ** The new command -info-ada-exceptions provides the equivalent of
1409 the new "info exceptions" command.
1411 * New system-wide configuration scripts
1412 A GDB installation now provides scripts suitable for use as system-wide
1413 configuration scripts for the following systems:
1417 * GDB now supports target-assigned range stepping with remote targets.
1418 This improves the performance of stepping source lines by reducing
1419 the number of control packets from/to GDB. See "New remote packets"
1422 * GDB now understands the element 'tvar' in the XML traceframe info.
1423 It has the id of the collected trace state variables.
1425 * On S/390 targets that provide the transactional-execution feature,
1426 the program interruption transaction diagnostic block (TDB) is now
1427 represented as a number of additional "registers" in GDB.
1429 * New remote packets
1433 The vCont packet supports a new 'r' action, that tells the remote
1434 stub to step through an address range itself, without GDB
1435 involvemement at each single-step.
1437 qXfer:libraries-svr4:read's annex
1438 The previously unused annex of the qXfer:libraries-svr4:read packet
1439 is now used to support passing an argument list. The remote stub
1440 reports support for this argument list to GDB's qSupported query.
1441 The defined arguments are "start" and "prev", used to reduce work
1442 necessary for library list updating, resulting in significant
1445 * New features in the GDB remote stub, GDBserver
1447 ** GDBserver now supports target-assisted range stepping. Currently
1448 enabled on x86/x86_64 GNU/Linux targets.
1450 ** GDBserver now adds element 'tvar' in the XML in the reply to
1451 'qXfer:traceframe-info:read'. It has the id of the collected
1452 trace state variables.
1454 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1457 * New 'z' formatter for printing and examining memory, this displays the
1458 value as hexadecimal zero padded on the left to the size of the type.
1460 * GDB can now use Windows x64 unwinding data.
1462 * The "set remotebaud" command has been replaced by "set serial baud".
1463 Similarly, "show remotebaud" has been replaced by "show serial baud".
1464 The "set remotebaud" and "show remotebaud" commands are still available
1465 to provide backward compatibility with older versions of GDB.
1467 *** Changes in GDB 7.6
1469 * Target record has been renamed to record-full.
1470 Record/replay is now enabled with the "record full" command.
1471 This also affects settings that are associated with full record/replay
1472 that have been moved from "set/show record" to "set/show record full":
1474 set|show record full insn-number-max
1475 set|show record full stop-at-limit
1476 set|show record full memory-query
1478 * A new record target "record-btrace" has been added. The new target
1479 uses hardware support to record the control-flow of a process. It
1480 does not support replaying the execution, but it implements the
1481 below new commands for investigating the recorded execution log.
1482 This new recording method can be enabled using:
1486 The "record-btrace" target is only available on Intel Atom processors
1487 and requires a Linux kernel 2.6.32 or later.
1489 * Two new commands have been added for record/replay to give information
1490 about the recorded execution without having to replay the execution.
1491 The commands are only supported by "record btrace".
1493 record instruction-history prints the execution history at
1494 instruction granularity
1496 record function-call-history prints the execution history at
1497 function granularity
1499 * New native configurations
1501 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1502 FreeBSD/powerpc powerpc*-*-freebsd
1503 x86_64/Cygwin x86_64-*-cygwin*
1504 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1508 ARM AArch64 aarch64*-*-elf
1509 ARM AArch64 GNU/Linux aarch64*-*-linux
1510 Lynx 178 PowerPC powerpc-*-lynx*178
1511 x86_64/Cygwin x86_64-*-cygwin*
1512 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1514 * If the configured location of system.gdbinit file (as given by the
1515 --with-system-gdbinit option at configure time) is in the
1516 data-directory (as specified by --with-gdb-datadir at configure
1517 time) or in one of its subdirectories, then GDB will look for the
1518 system-wide init file in the directory specified by the
1519 --data-directory command-line option.
1521 * New command line options:
1523 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1524 other initialization files, unlike -nx which disables all of them.
1526 * Removed command line options
1528 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1531 * The 'ptype' and 'whatis' commands now accept an argument to control
1534 * 'info proc' now works on some core files.
1538 ** Vectors can be created with gdb.Type.vector.
1540 ** Python's atexit.register now works in GDB.
1542 ** Types can be pretty-printed via a Python API.
1544 ** Python 3 is now supported (in addition to Python 2.4 or later)
1546 ** New class gdb.Architecture exposes GDB's internal representation
1547 of architecture in the Python API.
1549 ** New method Frame.architecture returns the gdb.Architecture object
1550 corresponding to the frame's architecture.
1552 * New Python-based convenience functions:
1554 ** $_memeq(buf1, buf2, length)
1555 ** $_streq(str1, str2)
1557 ** $_regex(str, regex)
1559 * The 'cd' command now defaults to using '~' (the home directory) if not
1562 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1563 default for GCC since November 2000.
1565 * The command 'forward-search' can now be abbreviated as 'fo'.
1567 * The command 'info tracepoints' can now display 'installed on target'
1568 or 'not installed on target' for each non-pending location of tracepoint.
1570 * New configure options
1572 --enable-libmcheck/--disable-libmcheck
1573 By default, development versions are built with -lmcheck on hosts
1574 that support it, in order to help track memory corruption issues.
1575 Release versions, on the other hand, are built without -lmcheck
1576 by default. The --enable-libmcheck/--disable-libmcheck configure
1577 options allow the user to override that default.
1578 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1579 This configure option allows the user to build GDB with
1580 libbabeltrace using which GDB can read Common Trace Format data.
1582 * New commands (for set/show, see "New options" below)
1585 Catch signals. This is similar to "handle", but allows commands and
1586 conditions to be attached.
1589 List the BFDs known to GDB.
1591 python-interactive [command]
1593 Start a Python interactive prompt, or evaluate the optional command
1594 and print the result of expressions.
1597 "py" is a new alias for "python".
1599 enable type-printer [name]...
1600 disable type-printer [name]...
1601 Enable or disable type printers.
1605 ** For the Renesas Super-H architecture, the "regs" command has been removed
1606 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1611 set print type methods (on|off)
1612 show print type methods
1613 Control whether method declarations are displayed by "ptype".
1614 The default is to show them.
1616 set print type typedefs (on|off)
1617 show print type typedefs
1618 Control whether typedef definitions are displayed by "ptype".
1619 The default is to show them.
1621 set filename-display basename|relative|absolute
1622 show filename-display
1623 Control the way in which filenames is displayed.
1624 The default is "relative", which preserves previous behavior.
1626 set trace-buffer-size
1627 show trace-buffer-size
1628 Request target to change the size of trace buffer.
1630 set remote trace-buffer-size-packet auto|on|off
1631 show remote trace-buffer-size-packet
1632 Control the use of the remote protocol `QTBuffer:size' packet.
1636 Control display of debugging messages related to ARM AArch64.
1639 set debug coff-pe-read
1640 show debug coff-pe-read
1641 Control display of debugging messages related to reading of COFF/PE
1646 Control display of debugging messages related to Mach-O symbols
1649 set debug notification
1650 show debug notification
1651 Control display of debugging info for async remote notification.
1655 ** Command parameter changes are now notified using new async record
1656 "=cmd-param-changed".
1657 ** Trace frame changes caused by command "tfind" are now notified using
1658 new async record "=traceframe-changed".
1659 ** The creation, deletion and modification of trace state variables
1660 are now notified using new async records "=tsv-created",
1661 "=tsv-deleted" and "=tsv-modified".
1662 ** The start and stop of process record are now notified using new
1663 async record "=record-started" and "=record-stopped".
1664 ** Memory changes are now notified using new async record
1666 ** The data-disassemble command response will include a "fullname" field
1667 containing the absolute file name when source has been requested.
1668 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1669 command, to allow pattern filling of memory areas.
1670 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1671 library load/unload events.
1672 ** The response to breakpoint commands and breakpoint async records
1673 includes an "installed" field containing a boolean state about each
1674 non-pending tracepoint location is whether installed on target or not.
1675 ** Output of the "-trace-status" command includes a "trace-file" field
1676 containing the name of the trace file being examined. This field is
1677 optional, and only present when examining a trace file.
1678 ** The "fullname" field is now always present along with the "file" field,
1679 even if the file cannot be found by GDB.
1681 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1682 You must have the LZMA library available when configuring GDB for this
1683 feature to be enabled. For more information, see:
1684 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1686 * New remote packets
1689 Set the size of trace buffer. The remote stub reports support for this
1690 packet to gdb's qSupported query.
1693 Enable Branch Trace Store (BTS)-based branch tracing for the current
1694 thread. The remote stub reports support for this packet to gdb's
1698 Disable branch tracing for the current thread. The remote stub reports
1699 support for this packet to gdb's qSupported query.
1702 Read the traced branches for the current thread. The remote stub
1703 reports support for this packet to gdb's qSupported query.
1705 *** Changes in GDB 7.5
1707 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1708 for more x32 ABI info.
1710 * GDB now supports access to MIPS DSP registers on Linux targets.
1712 * GDB now supports debugging microMIPS binaries.
1714 * The "info os" command on GNU/Linux can now display information on
1715 several new classes of objects managed by the operating system:
1716 "info os procgroups" lists process groups
1717 "info os files" lists file descriptors
1718 "info os sockets" lists internet-domain sockets
1719 "info os shm" lists shared-memory regions
1720 "info os semaphores" lists semaphores
1721 "info os msg" lists message queues
1722 "info os modules" lists loaded kernel modules
1724 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1725 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1726 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1727 options and inspect the probe arguments using the new $_probe_arg family
1728 of convenience variables. You can obtain more information about SystemTap
1729 in <http://sourceware.org/systemtap/>.
1731 * GDB now supports reversible debugging on ARM, it allows you to
1732 debug basic ARM and THUMB instructions, and provides
1733 record/replay support.
1735 * The option "symbol-reloading" has been deleted as it is no longer used.
1739 ** GDB commands implemented in Python can now be put in command class
1742 ** The "maint set python print-stack on|off" is now deleted.
1744 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1745 apply "flag enum"-style pretty-printing to any enum.
1747 ** gdb.lookup_symbol can now work when there is no current frame.
1749 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1750 the source at which the symbol was defined.
1752 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1753 method 'value'. The former indicates whether the symbol needs a
1754 frame in order to compute its value, and the latter computes the
1757 ** A new method 'referenced_value' on gdb.Value objects which can
1758 dereference pointer as well as C++ reference values.
1760 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1761 which return the global and static blocks (as gdb.Block objects),
1762 of the underlying symbol table, respectively.
1764 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1765 object associated with a PC value.
1767 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1768 of the address range occupied by code for the current source line.
1770 * Go language support.
1771 GDB now supports debugging programs written in the Go programming
1774 * GDBserver now supports stdio connections.
1775 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1777 * The binary "gdbtui" can no longer be built or installed.
1778 Use "gdb -tui" instead.
1780 * GDB will now print "flag" enums specially. A flag enum is one where
1781 all the enumerator values have no bits in common when pairwise
1782 "and"ed. When printing a value whose type is a flag enum, GDB will
1783 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1784 (gdb) print (enum E) 3
1787 * The filename part of a linespec will now match trailing components
1788 of a source file name. For example, "break gcc/expr.c:1000" will
1789 now set a breakpoint in build/gcc/expr.c, but not
1790 build/libcpp/expr.c.
1792 * The "info proc" and "generate-core-file" commands will now also
1793 work on remote targets connected to GDBserver on Linux.
1795 * The command "info catch" has been removed. It has been disabled
1796 since December 2007.
1798 * The "catch exception" and "catch assert" commands now accept
1799 a condition at the end of the command, much like the "break"
1800 command does. For instance:
1802 (gdb) catch exception Constraint_Error if Barrier = True
1804 Previously, it was possible to add a condition to such catchpoints,
1805 but it had to be done as a second step, after the catchpoint had been
1806 created, using the "condition" command.
1808 * The "info static-tracepoint-marker" command will now also work on
1809 native Linux targets with in-process agent.
1811 * GDB can now set breakpoints on inlined functions.
1813 * The .gdb_index section has been updated to include symbols for
1814 inlined functions. GDB will ignore older .gdb_index sections by
1815 default, which could cause symbol files to be loaded more slowly
1816 until their .gdb_index sections can be recreated. The new command
1817 "set use-deprecated-index-sections on" will cause GDB to use any older
1818 .gdb_index sections it finds. This will restore performance, but the
1819 ability to set breakpoints on inlined functions will be lost in symbol
1820 files with older .gdb_index sections.
1822 The .gdb_index section has also been updated to record more information
1823 about each symbol. This speeds up the "info variables", "info functions"
1824 and "info types" commands when used with programs having the .gdb_index
1825 section, as well as speeding up debugging with shared libraries using
1826 the .gdb_index section.
1828 * Ada support for GDB/MI Variable Objects has been added.
1830 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1835 ** New command -info-os is the MI equivalent of "info os".
1837 ** Output logs ("set logging" and related) now include MI output.
1841 ** "set use-deprecated-index-sections on|off"
1842 "show use-deprecated-index-sections on|off"
1843 Controls the use of deprecated .gdb_index sections.
1845 ** "catch load" and "catch unload" can be used to stop when a shared
1846 library is loaded or unloaded, respectively.
1848 ** "enable count" can be used to auto-disable a breakpoint after
1851 ** "info vtbl" can be used to show the virtual method tables for
1852 C++ and Java objects.
1854 ** "explore" and its sub commands "explore value" and "explore type"
1855 can be used to recursively explore values and types of
1856 expressions. These commands are available only if GDB is
1857 configured with '--with-python'.
1859 ** "info auto-load" shows status of all kinds of auto-loaded files,
1860 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1861 sequences of commands files, "info auto-load python-scripts"
1862 shows status of auto-loading Python script files,
1863 "info auto-load local-gdbinit" shows status of loading init file
1864 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1865 status of inferior specific thread debugging shared library loading.
1867 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1868 and "show auto-load-scripts" commands have been deprecated, use their
1869 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1870 and "show auto-load python-scripts" counterparts instead.
1872 ** "dprintf location,format,args..." creates a dynamic printf, which
1873 is basically a breakpoint that does a printf and immediately
1874 resumes your program's execution, so it is like a printf that you
1875 can insert dynamically at runtime instead of at compiletime.
1877 ** "set print symbol"
1879 Controls whether GDB attempts to display the symbol, if any,
1880 corresponding to addresses it prints. This defaults to "on", but
1881 you can set it to "off" to restore GDB's previous behavior.
1883 * Deprecated commands
1885 ** For the Renesas Super-H architecture, the "regs" command has been
1886 deprecated, and "info all-registers" should be used instead.
1890 Renesas RL78 rl78-*-elf
1891 HP OpenVMS ia64 ia64-hp-openvms*
1893 * GDBserver supports evaluation of breakpoint conditions. When
1894 support is advertised by GDBserver, GDB may be told to send the
1895 breakpoint conditions in bytecode form to GDBserver. GDBserver
1896 will only report the breakpoint trigger to GDB when its condition
1901 set mips compression
1902 show mips compression
1903 Select the compressed ISA encoding used in functions that have no symbol
1904 information available. The encoding can be set to either of:
1907 and is updated automatically from ELF file flags if available.
1909 set breakpoint condition-evaluation
1910 show breakpoint condition-evaluation
1911 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1912 GDBserver ("target"). Default option "auto" chooses the most efficient
1914 This option can improve debugger efficiency depending on the speed of the
1918 Disable auto-loading globally.
1921 Show auto-loading setting of all kinds of auto-loaded files.
1923 set auto-load gdb-scripts on|off
1924 show auto-load gdb-scripts
1925 Control auto-loading of GDB canned sequences of commands files.
1927 set auto-load python-scripts on|off
1928 show auto-load python-scripts
1929 Control auto-loading of Python script files.
1931 set auto-load local-gdbinit on|off
1932 show auto-load local-gdbinit
1933 Control loading of init file (.gdbinit) from current directory.
1935 set auto-load libthread-db on|off
1936 show auto-load libthread-db
1937 Control auto-loading of inferior specific thread debugging shared library.
1939 set auto-load scripts-directory <dir1>[:<dir2>...]
1940 show auto-load scripts-directory
1941 Set a list of directories from which to load auto-loaded scripts.
1942 Automatically loaded Python scripts and GDB scripts are located in one
1943 of the directories listed by this option.
1944 The delimiter (':' above) may differ according to the host platform.
1946 set auto-load safe-path <dir1>[:<dir2>...]
1947 show auto-load safe-path
1948 Set a list of directories from which it is safe to auto-load files.
1949 The delimiter (':' above) may differ according to the host platform.
1951 set debug auto-load on|off
1952 show debug auto-load
1953 Control display of debugging info for auto-loading the files above.
1955 set dprintf-style gdb|call|agent
1957 Control the way in which a dynamic printf is performed; "gdb"
1958 requests a GDB printf command, while "call" causes dprintf to call a
1959 function in the inferior. "agent" requests that the target agent
1960 (such as GDBserver) do the printing.
1962 set dprintf-function <expr>
1963 show dprintf-function
1964 set dprintf-channel <expr>
1965 show dprintf-channel
1966 Set the function and optional first argument to the call when using
1967 the "call" style of dynamic printf.
1969 set disconnected-dprintf on|off
1970 show disconnected-dprintf
1971 Control whether agent-style dynamic printfs continue to be in effect
1972 after GDB disconnects.
1974 * New configure options
1976 --with-auto-load-dir
1977 Configure default value for the 'set auto-load scripts-directory'
1978 setting above. It defaults to '$debugdir:$datadir/auto-load',
1979 $debugdir representing global debugging info directories (available
1980 via 'show debug-file-directory') and $datadir representing GDB's data
1981 directory (available via 'show data-directory').
1983 --with-auto-load-safe-path
1984 Configure default value for the 'set auto-load safe-path' setting
1985 above. It defaults to the --with-auto-load-dir setting.
1987 --without-auto-load-safe-path
1988 Set 'set auto-load safe-path' to '/', effectively disabling this
1991 * New remote packets
1993 z0/z1 conditional breakpoints extension
1995 The z0/z1 breakpoint insertion packets have been extended to carry
1996 a list of conditional expressions over to the remote stub depending on the
1997 condition evaluation mode. The use of this extension can be controlled
1998 via the "set remote conditional-breakpoints-packet" command.
2002 Specify the signals which the remote stub may pass to the debugged
2003 program without GDB involvement.
2005 * New command line options
2007 --init-command=FILE, -ix Like --command, -x but execute it
2008 before loading inferior.
2009 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
2010 execute it before loading inferior.
2012 *** Changes in GDB 7.4
2014 * GDB now handles ambiguous linespecs more consistently; the existing
2015 FILE:LINE support has been expanded to other types of linespecs. A
2016 breakpoint will now be set on all matching locations in all
2017 inferiors, and locations will be added or removed according to
2020 * GDB now allows you to skip uninteresting functions and files when
2021 stepping with the "skip function" and "skip file" commands.
2023 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
2024 and "show remote hardware-watchpoint-length-limit". These allows to
2025 set or show the maximum length limit (in bytes) of a remote
2026 target hardware watchpoint.
2028 This allows e.g. to use "unlimited" hardware watchpoints with the
2029 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
2030 watchpoints are slower than real hardware watchpoints but are
2031 significantly faster than gdb software watchpoints.
2035 ** The register_pretty_printer function in module gdb.printing now takes
2036 an optional `replace' argument. If True, the new printer replaces any
2039 ** The "maint set python print-stack on|off" command has been
2040 deprecated and will be deleted in GDB 7.5.
2041 A new command: "set python print-stack none|full|message" has
2042 replaced it. Additionally, the default for "print-stack" is
2043 now "message", which just prints the error message without
2046 ** A prompt substitution hook (prompt_hook) is now available to the
2049 ** A new Python module, gdb.prompt has been added to the GDB Python
2050 modules library. This module provides functionality for
2051 escape sequences in prompts (used by set/show
2052 extended-prompt). These escape sequences are replaced by their
2053 corresponding value.
2055 ** Python commands and convenience-functions located in
2056 'data-directory'/python/gdb/command and
2057 'data-directory'/python/gdb/function are now automatically loaded
2060 ** Blocks now provide four new attributes. global_block and
2061 static_block will return the global and static blocks
2062 respectively. is_static and is_global are boolean attributes
2063 that indicate if the block is one of those two types.
2065 ** Symbols now provide the "type" attribute, the type of the symbol.
2067 ** The "gdb.breakpoint" function has been deprecated in favor of
2070 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2071 of a function. This class is based on the "finish" command
2072 available in the CLI.
2074 ** Type objects for struct and union types now allow access to
2075 the fields using standard Python dictionary (mapping) methods.
2076 For example, "some_type['myfield']" now works, as does
2077 "some_type.items()".
2079 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2082 ** A new function, "deep_items" has been added to the gdb.types
2083 module in the GDB Python modules library. This function returns
2084 an iterator over the fields of a struct or union type. Unlike
2085 the standard Python "iteritems" method, it will recursively traverse
2086 any anonymous fields.
2090 ** "*stopped" events can report several new "reason"s, such as
2093 ** Breakpoint changes are now notified using new async records, like
2094 "=breakpoint-modified".
2096 ** New command -ada-task-info.
2098 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2099 $sdir specifies the default system locations of shared libraries.
2100 $pdir specifies the directory where the libpthread used by the application
2103 GDB no longer looks in $sdir and $pdir after it has searched the directories
2104 mentioned in libthread-db-search-path. If you want to search those
2105 directories, they must be specified in libthread-db-search-path.
2106 The default value of libthread-db-search-path on GNU/Linux and Solaris
2107 systems is now "$sdir:$pdir".
2109 $pdir is not supported by gdbserver, it is currently ignored.
2110 $sdir is supported by gdbserver.
2112 * New configure option --with-iconv-bin.
2113 When using the internationalization support like the one in the GNU C
2114 library, GDB will invoke the "iconv" program to get a list of supported
2115 character sets. If this program lives in a non-standard location, one can
2116 use this option to specify where to find it.
2118 * When natively debugging programs on PowerPC BookE processors running
2119 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2120 watchpoints, which specify a mask in addition to an address to watch.
2121 The mask specifies that some bits of an address (the bits which are
2122 reset in the mask) should be ignored when matching the address accessed
2123 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2124 section in the user manual for more details.
2126 * The new option --once causes GDBserver to stop listening for connections once
2127 the first connection is made. The listening port used by GDBserver will
2128 become available after that.
2130 * New commands "info macros" and "alias" have been added.
2132 * New function parameters suffix @entry specifies value of function parameter
2133 at the time the function got called. Entry values are available only since
2139 "!" is now an alias of the "shell" command.
2140 Note that no space is needed between "!" and SHELL COMMAND.
2144 watch EXPRESSION mask MASK_VALUE
2145 The watch command now supports the mask argument which allows creation
2146 of masked watchpoints, if the current architecture supports this feature.
2148 info auto-load-scripts [REGEXP]
2149 This command was formerly named "maintenance print section-scripts".
2150 It is now generally useful and is no longer a maintenance-only command.
2152 info macro [-all] [--] MACRO
2153 The info macro command has new options `-all' and `--'. The first for
2154 printing all definitions of a macro. The second for explicitly specifying
2155 the end of arguments and the beginning of the macro name in case the macro
2156 name starts with a hyphen.
2158 collect[/s] EXPRESSIONS
2159 The tracepoint collect command now takes an optional modifier "/s"
2160 that directs it to dereference pointer-to-character types and
2161 collect the bytes of memory up to a zero byte. The behavior is
2162 similar to what you see when you use the regular print command on a
2163 string. An optional integer following the "/s" sets a bound on the
2164 number of bytes that will be collected.
2167 The trace start command now interprets any supplied arguments as a
2168 note to be recorded with the trace run, with an effect similar to
2169 setting the variable trace-notes.
2172 The trace stop command now interprets any arguments as a note to be
2173 mentioned along with the tstatus report that the trace was stopped
2174 with a command. The effect is similar to setting the variable
2177 * Tracepoints can now be enabled and disabled at any time after a trace
2178 experiment has been started using the standard "enable" and "disable"
2179 commands. It is now possible to start a trace experiment with no enabled
2180 tracepoints; GDB will display a warning, but will allow the experiment to
2181 begin, assuming that tracepoints will be enabled as needed while the trace
2184 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2185 locations with 4-byte instructions, when they were previously
2186 limited to locations with instructions of 5 bytes or longer.
2190 set debug dwarf2-read
2191 show debug dwarf2-read
2192 Turns on or off display of debugging messages related to reading
2193 DWARF debug info. The default is off.
2195 set debug symtab-create
2196 show debug symtab-create
2197 Turns on or off display of debugging messages related to symbol table
2198 creation. The default is off.
2201 show extended-prompt
2202 Set the GDB prompt, and allow escape sequences to be inserted to
2203 display miscellaneous information (see 'help set extended-prompt'
2204 for the list of sequences). This prompt (and any information
2205 accessed through the escape sequences) is updated every time the
2206 prompt is displayed.
2208 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2209 show print entry-values
2210 Set printing of frame argument values at function entry. In some cases
2211 GDB can determine the value of function argument which was passed by the
2212 function caller, even if the value was modified inside the called function.
2214 set debug entry-values
2215 show debug entry-values
2216 Control display of debugging info for determining frame argument values at
2217 function entry and virtual tail call frames.
2219 set basenames-may-differ
2220 show basenames-may-differ
2221 Set whether a source file may have multiple base names.
2222 (A "base name" is the name of a file with the directory part removed.
2223 Example: The base name of "/home/user/hello.c" is "hello.c".)
2224 If set, GDB will canonicalize file names (e.g., expand symlinks)
2225 before comparing them. Canonicalization is an expensive operation,
2226 but it allows the same file be known by more than one base name.
2227 If not set (the default), all source files are assumed to have just
2228 one base name, and gdb will do file name comparisons more efficiently.
2234 Set a user name and notes for the current and any future trace runs.
2235 This is useful for long-running and/or disconnected traces, to
2236 inform others (or yourself) as to who is running the trace, supply
2237 contact information, or otherwise explain what is going on.
2239 set trace-stop-notes
2240 show trace-stop-notes
2241 Set a note attached to the trace run, that is displayed when the
2242 trace has been stopped by a tstop command. This is useful for
2243 instance as an explanation, if you are stopping a trace run that was
2244 started by someone else.
2246 * New remote packets
2250 Dynamically enable a tracepoint in a started trace experiment.
2254 Dynamically disable a tracepoint in a started trace experiment.
2258 Set the user and notes of the trace run.
2262 Query the current status of a tracepoint.
2266 Query the minimum length of instruction at which a fast tracepoint may
2269 * Dcache size (number of lines) and line-size are now runtime-configurable
2270 via "set dcache line" and "set dcache line-size" commands.
2274 Texas Instruments TMS320C6x tic6x-*-*
2278 Renesas RL78 rl78-*-elf
2280 *** Changes in GDB 7.3.1
2282 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2284 *** Changes in GDB 7.3
2286 * GDB has a new command: "thread find [REGEXP]".
2287 It finds the thread id whose name, target id, or thread extra info
2288 matches the given regular expression.
2290 * The "catch syscall" command now works on mips*-linux* targets.
2292 * The -data-disassemble MI command now supports modes 2 and 3 for
2293 dumping the instruction opcodes.
2295 * New command line options
2297 -data-directory DIR Specify DIR as the "data-directory".
2298 This is mostly for testing purposes.
2300 * The "maint set python auto-load on|off" command has been renamed to
2301 "set auto-load-scripts on|off".
2303 * GDB has a new command: "set directories".
2304 It is like the "dir" command except that it replaces the
2305 source path list instead of augmenting it.
2307 * GDB now understands thread names.
2309 On GNU/Linux, "info threads" will display the thread name as set by
2310 prctl or pthread_setname_np.
2312 There is also a new command, "thread name", which can be used to
2313 assign a name internally for GDB to display.
2316 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2317 has been integrated into GDB.
2321 ** The function gdb.Write now accepts an optional keyword 'stream'.
2322 This keyword, when provided, will direct the output to either
2323 stdout, stderr, or GDB's logging output.
2325 ** Parameters can now be be sub-classed in Python, and in particular
2326 you may implement the get_set_doc and get_show_doc functions.
2327 This improves how Parameter set/show documentation is processed
2328 and allows for more dynamic content.
2330 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2331 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2332 have an is_valid method.
2334 ** Breakpoints can now be sub-classed in Python, and in particular
2335 you may implement a 'stop' function that is executed each time
2336 the inferior reaches that breakpoint.
2338 ** New function gdb.lookup_global_symbol looks up a global symbol.
2340 ** GDB values in Python are now callable if the value represents a
2341 function. For example, if 'some_value' represents a function that
2342 takes two integer parameters and returns a value, you can call
2343 that function like so:
2345 result = some_value (10,20)
2347 ** Module gdb.types has been added.
2348 It contains a collection of utilities for working with gdb.Types objects:
2349 get_basic_type, has_field, make_enum_dict.
2351 ** Module gdb.printing has been added.
2352 It contains utilities for writing and registering pretty-printers.
2353 New classes: PrettyPrinter, SubPrettyPrinter,
2354 RegexpCollectionPrettyPrinter.
2355 New function: register_pretty_printer.
2357 ** New commands "info pretty-printers", "enable pretty-printer" and
2358 "disable pretty-printer" have been added.
2360 ** gdb.parameter("directories") is now available.
2362 ** New function gdb.newest_frame returns the newest frame in the
2365 ** The gdb.InferiorThread class has a new "name" attribute. This
2366 holds the thread's name.
2368 ** Python Support for Inferior events.
2369 Python scripts can add observers to be notified of events
2370 occurring in the process being debugged.
2371 The following events are currently supported:
2372 - gdb.events.cont Continue event.
2373 - gdb.events.exited Inferior exited event.
2374 - gdb.events.stop Signal received, and Breakpoint hit events.
2378 ** GDB now puts template parameters in scope when debugging in an
2379 instantiation. For example, if you have:
2381 template<int X> int func (void) { return X; }
2383 then if you step into func<5>, "print X" will show "5". This
2384 feature requires proper debuginfo support from the compiler; it
2385 was added to GCC 4.5.
2387 ** The motion commands "next", "finish", "until", and "advance" now
2388 work better when exceptions are thrown. In particular, GDB will
2389 no longer lose control of the inferior; instead, the GDB will
2390 stop the inferior at the point at which the exception is caught.
2391 This functionality requires a change in the exception handling
2392 code that was introduced in GCC 4.5.
2394 * GDB now follows GCC's rules on accessing volatile objects when
2395 reading or writing target state during expression evaluation.
2396 One notable difference to prior behavior is that "print x = 0"
2397 no longer generates a read of x; the value of the assignment is
2398 now always taken directly from the value being assigned.
2400 * GDB now has some support for using labels in the program's source in
2401 linespecs. For instance, you can use "advance label" to continue
2402 execution to a label.
2404 * GDB now has support for reading and writing a new .gdb_index
2405 section. This section holds a fast index of DWARF debugging
2406 information and can be used to greatly speed up GDB startup and
2407 operation. See the documentation for `save gdb-index' for details.
2409 * The "watch" command now accepts an optional "-location" argument.
2410 When used, this causes GDB to watch the memory referred to by the
2411 expression. Such a watchpoint is never deleted due to it going out
2414 * GDB now supports thread debugging of core dumps on GNU/Linux.
2416 GDB now activates thread debugging using the libthread_db library
2417 when debugging GNU/Linux core dumps, similarly to when debugging
2418 live processes. As a result, when debugging a core dump file, GDB
2419 is now able to display pthread_t ids of threads. For example, "info
2420 threads" shows the same output as when debugging the process when it
2421 was live. In earlier releases, you'd see something like this:
2424 * 1 LWP 6780 main () at main.c:10
2426 While now you see this:
2429 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2431 It is also now possible to inspect TLS variables when debugging core
2434 When debugging a core dump generated on a machine other than the one
2435 used to run GDB, you may need to point GDB at the correct
2436 libthread_db library with the "set libthread-db-search-path"
2437 command. See the user manual for more details on this command.
2439 * When natively debugging programs on PowerPC BookE processors running
2440 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2441 which stop execution of the inferior whenever it executes an instruction
2442 at any address within the specified range. See the "PowerPC Embedded"
2443 section in the user manual for more details.
2445 * New features in the GDB remote stub, GDBserver
2447 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2448 and i686 LynxOS (version 5.x).
2450 ** GDBserver is now supported on Blackfin Linux.
2452 * New native configurations
2454 ia64 HP-UX ia64-*-hpux*
2458 Analog Devices, Inc. Blackfin Processor bfin-*
2460 * Ada task switching is now supported on sparc-elf targets when
2461 debugging a program using the Ravenscar Profile. For more information,
2462 see the "Tasking Support when using the Ravenscar Profile" section
2463 in the GDB user manual.
2465 * Guile support was removed.
2467 * New features in the GNU simulator
2469 ** The --map-info flag lists all known core mappings.
2471 ** CFI flashes may be simulated via the "cfi" device.
2473 *** Changes in GDB 7.2
2475 * Shared library support for remote targets by default
2477 When GDB is configured for a generic, non-OS specific target, like
2478 for example, --target=arm-eabi or one of the many *-*-elf targets,
2479 GDB now queries remote stubs for loaded shared libraries using the
2480 `qXfer:libraries:read' packet. Previously, shared library support
2481 was always disabled for such configurations.
2485 ** Argument Dependent Lookup (ADL)
2487 In C++ ADL lookup directs function search to the namespaces of its
2488 arguments even if the namespace has not been imported.
2498 Here the compiler will search for `foo' in the namespace of 'b'
2499 and find A::foo. GDB now supports this. This construct is commonly
2500 used in the Standard Template Library for operators.
2502 ** Improved User Defined Operator Support
2504 In addition to member operators, GDB now supports lookup of operators
2505 defined in a namespace and imported with a `using' directive, operators
2506 defined in the global scope, operators imported implicitly from an
2507 anonymous namespace, and the ADL operators mentioned in the previous
2509 GDB now also supports proper overload resolution for all the previously
2510 mentioned flavors of operators.
2512 ** static const class members
2514 Printing of static const class members that are initialized in the
2515 class definition has been fixed.
2517 * Windows Thread Information Block access.
2519 On Windows targets, GDB now supports displaying the Windows Thread
2520 Information Block (TIB) structure. This structure is visible either
2521 by using the new command `info w32 thread-information-block' or, by
2522 dereferencing the new convenience variable named `$_tlb', a
2523 thread-specific pointer to the TIB. This feature is also supported
2524 when remote debugging using GDBserver.
2526 * Static tracepoints
2528 Static tracepoints are calls in the user program into a tracing
2529 library. One such library is a port of the LTTng kernel tracer to
2530 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2531 When debugging with GDBserver, GDB now supports combining the GDB
2532 tracepoint machinery with such libraries. For example: the user can
2533 use GDB to probe a static tracepoint marker (a call from the user
2534 program into the tracing library) with the new "strace" command (see
2535 "New commands" below). This creates a "static tracepoint" in the
2536 breakpoint list, that can be manipulated with the same feature set
2537 as fast and regular tracepoints. E.g., collect registers, local and
2538 global variables, collect trace state variables, and define
2539 tracepoint conditions. In addition, the user can collect extra
2540 static tracepoint marker specific data, by collecting the new
2541 $_sdata internal variable. When analyzing the trace buffer, you can
2542 inspect $_sdata like any other variable available to GDB. For more
2543 information, see the "Tracepoints" chapter in GDB user manual. New
2544 remote packets have been defined to support static tracepoints, see
2545 the "New remote packets" section below.
2547 * Better reconstruction of tracepoints after disconnected tracing
2549 GDB will attempt to download the original source form of tracepoint
2550 definitions when starting a trace run, and then will upload these
2551 upon reconnection to the target, resulting in a more accurate
2552 reconstruction of the tracepoints that are in use on the target.
2556 You can now exercise direct control over the ways that GDB can
2557 affect your program. For instance, you can disallow the setting of
2558 breakpoints, so that the program can run continuously (assuming
2559 non-stop mode). In addition, the "observer" variable is available
2560 to switch all of the different controls; in observer mode, GDB
2561 cannot affect the target's behavior at all, which is useful for
2562 tasks like diagnosing live systems in the field.
2564 * The new convenience variable $_thread holds the number of the
2567 * New remote packets
2571 Return the address of the Windows Thread Information Block of a given thread.
2575 In response to several of the tracepoint packets, the target may now
2576 also respond with a number of intermediate `qRelocInsn' request
2577 packets before the final result packet, to have GDB handle
2578 relocating an instruction to execute at a different address. This
2579 is particularly useful for stubs that support fast tracepoints. GDB
2580 reports support for this feature in the qSupported packet.
2584 List static tracepoint markers in the target program.
2588 List static tracepoint markers at a given address in the target
2591 qXfer:statictrace:read
2593 Read the static trace data collected (by a `collect $_sdata'
2594 tracepoint action). The remote stub reports support for this packet
2595 to gdb's qSupported query.
2599 Send the current settings of GDB's permission flags.
2603 Send part of the source (textual) form of a tracepoint definition,
2604 which includes location, conditional, and action list.
2606 * The source command now accepts a -s option to force searching for the
2607 script in the source search path even if the script name specifies
2610 * New features in the GDB remote stub, GDBserver
2612 - GDBserver now support tracepoints (including fast tracepoints, and
2613 static tracepoints). The feature is currently supported by the
2614 i386-linux and amd64-linux builds. See the "Tracepoints support
2615 in gdbserver" section in the manual for more information.
2617 GDBserver JIT compiles the tracepoint's conditional agent
2618 expression bytecode into native code whenever possible for low
2619 overhead dynamic tracepoints conditionals. For such tracepoints,
2620 an expression that examines program state is evaluated when the
2621 tracepoint is reached, in order to determine whether to capture
2622 trace data. If the condition is simple and false, processing the
2623 tracepoint finishes very quickly and no data is gathered.
2625 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2626 for static tracepoints support.
2628 - GDBserver now supports x86_64 Windows 64-bit debugging.
2630 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2631 it understands register description.
2633 * The --batch flag now disables pagination and queries.
2635 * X86 general purpose registers
2637 GDB now supports reading/writing byte, word and double-word x86
2638 general purpose registers directly. This means you can use, say,
2639 $ah or $ax to refer, respectively, to the byte register AH and
2640 16-bit word register AX that are actually portions of the 32-bit
2641 register EAX or 64-bit register RAX.
2643 * The `commands' command now accepts a range of breakpoints to modify.
2644 A plain `commands' following a command that creates multiple
2645 breakpoints affects all the breakpoints set by that command. This
2646 applies to breakpoints set by `rbreak', and also applies when a
2647 single `break' command creates multiple breakpoints (e.g.,
2648 breakpoints on overloaded c++ functions).
2650 * The `rbreak' command now accepts a filename specification as part of
2651 its argument, limiting the functions selected by the regex to those
2652 in the specified file.
2654 * Support for remote debugging Windows and SymbianOS shared libraries
2655 from Unix hosts has been improved. Non Windows GDB builds now can
2656 understand target reported file names that follow MS-DOS based file
2657 system semantics, such as file names that include drive letters and
2658 use the backslash character as directory separator. This makes it
2659 possible to transparently use the "set sysroot" and "set
2660 solib-search-path" on Unix hosts to point as host copies of the
2661 target's shared libraries. See the new command "set
2662 target-file-system-kind" described below, and the "Commands to
2663 specify files" section in the user manual for more information.
2667 eval template, expressions...
2668 Convert the values of one or more expressions under the control
2669 of the string template to a command line, and call it.
2671 set target-file-system-kind unix|dos-based|auto
2672 show target-file-system-kind
2673 Set or show the assumed file system kind for target reported file
2676 save breakpoints <filename>
2677 Save all current breakpoint definitions to a file suitable for use
2678 in a later debugging session. To read the saved breakpoint
2679 definitions, use the `source' command.
2681 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2684 info static-tracepoint-markers
2685 Display information about static tracepoint markers in the target.
2687 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2688 Define a static tracepoint by probing a marker at the given
2689 function, line, address, or marker ID.
2693 Enable and disable observer mode.
2695 set may-write-registers on|off
2696 set may-write-memory on|off
2697 set may-insert-breakpoints on|off
2698 set may-insert-tracepoints on|off
2699 set may-insert-fast-tracepoints on|off
2700 set may-interrupt on|off
2701 Set individual permissions for GDB effects on the target. Note that
2702 some of these settings can have undesirable or surprising
2703 consequences, particularly when changed in the middle of a session.
2704 For instance, disabling the writing of memory can prevent
2705 breakpoints from being inserted, cause single-stepping to fail, or
2706 even crash your program, if you disable after breakpoints have been
2707 inserted. However, GDB should not crash.
2709 set record memory-query on|off
2710 show record memory-query
2711 Control whether to stop the inferior if memory changes caused
2712 by an instruction cannot be recorded.
2717 The disassemble command now supports "start,+length" form of two arguments.
2721 ** GDB now provides a new directory location, called the python directory,
2722 where Python scripts written for GDB can be installed. The location
2723 of that directory is <data-directory>/python, where <data-directory>
2724 is the GDB data directory. For more details, see section `Scripting
2725 GDB using Python' in the manual.
2727 ** The GDB Python API now has access to breakpoints, symbols, symbol
2728 tables, program spaces, inferiors, threads and frame's code blocks.
2729 Additionally, GDB Parameters can now be created from the API, and
2730 manipulated via set/show in the CLI.
2732 ** New functions gdb.target_charset, gdb.target_wide_charset,
2733 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2735 ** New exception gdb.GdbError.
2737 ** Pretty-printers are now also looked up in the current program space.
2739 ** Pretty-printers can now be individually enabled and disabled.
2741 ** GDB now looks for names of Python scripts to auto-load in a
2742 special section named `.debug_gdb_scripts', in addition to looking
2743 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2745 * Tracepoint actions were unified with breakpoint commands. In particular,
2746 there are no longer differences in "info break" output for breakpoints and
2747 tracepoints and the "commands" command can be used for both tracepoints and
2748 regular breakpoints.
2752 ARM Symbian arm*-*-symbianelf*
2754 * D language support.
2755 GDB now supports debugging programs written in the D programming
2758 * GDB now supports the extended ptrace interface for PowerPC which is
2759 available since Linux kernel version 2.6.34. This automatically enables
2760 any hardware breakpoints and additional hardware watchpoints available in
2761 the processor. The old ptrace interface exposes just one hardware
2762 watchpoint and no hardware breakpoints.
2764 * GDB is now able to use the Data Value Compare (DVC) register available on
2765 embedded PowerPC processors to implement in hardware simple watchpoint
2766 conditions of the form:
2768 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2770 This works in native GDB running on Linux kernels with the extended ptrace
2771 interface mentioned above.
2773 *** Changes in GDB 7.1
2777 ** Namespace Support
2779 GDB now supports importing of namespaces in C++. This enables the
2780 user to inspect variables from imported namespaces. Support for
2781 namepace aliasing has also been added. So, if a namespace is
2782 aliased in the current scope (e.g. namepace C=A; ) the user can
2783 print variables using the alias (e.g. (gdb) print C::x).
2787 All known bugs relating to the printing of virtual base class were
2788 fixed. It is now possible to call overloaded static methods using a
2793 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2794 and reinterpret_cast<> are now handled by the C++ expression parser.
2798 Xilinx MicroBlaze microblaze-*-*
2803 Xilinx MicroBlaze microblaze
2806 * Multi-program debugging.
2808 GDB now has support for multi-program (a.k.a. multi-executable or
2809 multi-exec) debugging. This allows for debugging multiple inferiors
2810 simultaneously each running a different program under the same GDB
2811 session. See "Debugging Multiple Inferiors and Programs" in the
2812 manual for more information. This implied some user visible changes
2813 in the multi-inferior support. For example, "info inferiors" now
2814 lists inferiors that are not running yet or that have exited
2815 already. See also "New commands" and "New options" below.
2817 * New tracing features
2819 GDB's tracepoint facility now includes several new features:
2821 ** Trace state variables
2823 GDB tracepoints now include support for trace state variables, which
2824 are variables managed by the target agent during a tracing
2825 experiment. They are useful for tracepoints that trigger each
2826 other, so for instance one tracepoint can count hits in a variable,
2827 and then a second tracepoint has a condition that is true when the
2828 count reaches a particular value. Trace state variables share the
2829 $-syntax of GDB convenience variables, and can appear in both
2830 tracepoint actions and condition expressions. Use the "tvariable"
2831 command to create, and "info tvariables" to view; see "Trace State
2832 Variables" in the manual for more detail.
2836 GDB now includes an option for defining fast tracepoints, which
2837 targets may implement more efficiently, such as by installing a jump
2838 into the target agent rather than a trap instruction. The resulting
2839 speedup can be by two orders of magnitude or more, although the
2840 tradeoff is that some program locations on some target architectures
2841 might not allow fast tracepoint installation, for instance if the
2842 instruction to be replaced is shorter than the jump. To request a
2843 fast tracepoint, use the "ftrace" command, with syntax identical to
2844 the regular trace command.
2846 ** Disconnected tracing
2848 It is now possible to detach GDB from the target while it is running
2849 a trace experiment, then reconnect later to see how the experiment
2850 is going. In addition, a new variable disconnected-tracing lets you
2851 tell the target agent whether to continue running a trace if the
2852 connection is lost unexpectedly.
2856 GDB now has the ability to save the trace buffer into a file, and
2857 then use that file as a target, similarly to you can do with
2858 corefiles. You can select trace frames, print data that was
2859 collected in them, and use tstatus to display the state of the
2860 tracing run at the moment that it was saved. To create a trace
2861 file, use "tsave <filename>", and to use it, do "target tfile
2864 ** Circular trace buffer
2866 You can ask the target agent to handle the trace buffer as a
2867 circular buffer, discarding the oldest trace frames to make room for
2868 newer ones, by setting circular-trace-buffer to on. This feature may
2869 not be available for all target agents.
2874 The disassemble command, when invoked with two arguments, now requires
2875 the arguments to be comma-separated.
2878 The info variables command now displays variable definitions. Files
2879 which only declare a variable are not shown.
2882 The source command is now capable of sourcing Python scripts.
2883 This feature is dependent on the debugger being build with Python
2886 Related to this enhancement is also the introduction of a new command
2887 "set script-extension" (see below).
2889 * New commands (for set/show, see "New options" below)
2891 record save [<FILENAME>]
2892 Save a file (in core file format) containing the process record
2893 execution log for replay debugging at a later time.
2895 record restore <FILENAME>
2896 Restore the process record execution log that was saved at an
2897 earlier time, for replay debugging.
2899 add-inferior [-copies <N>] [-exec <FILENAME>]
2902 clone-inferior [-copies <N>] [ID]
2903 Make a new inferior ready to execute the same program another
2904 inferior has loaded.
2909 maint info program-spaces
2910 List the program spaces loaded into GDB.
2912 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2913 show remote interrupt-sequence
2914 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2915 as the sequence to the remote target in order to interrupt the execution.
2916 Ctrl-C is a default. Some system prefers BREAK which is high level of
2917 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2918 Magic SysRq g. It is BREAK signal and character 'g'.
2920 set remote interrupt-on-connect [on | off]
2921 show remote interrupt-on-connect
2922 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2923 remote target when gdb connects to it. This is needed when you debug
2926 set remotebreak [on | off]
2928 Deprecated. Use "set/show remote interrupt-sequence" instead.
2930 tvariable $NAME [ = EXP ]
2931 Create or modify a trace state variable.
2934 List trace state variables and their values.
2936 delete tvariable $NAME ...
2937 Delete one or more trace state variables.
2940 Evaluate the given expressions without collecting anything into the
2941 trace buffer. (Valid in tracepoint actions only.)
2943 ftrace FN / FILE:LINE / *ADDR
2944 Define a fast tracepoint at the given function, line, or address.
2946 * New expression syntax
2948 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2949 GDB now parses 0b101010 identically with 42.
2953 set follow-exec-mode new|same
2954 show follow-exec-mode
2955 Control whether GDB reuses the same inferior across an exec call or
2956 creates a new one. This is useful to be able to restart the old
2957 executable after the inferior having done an exec call.
2959 set default-collect EXPR, ...
2960 show default-collect
2961 Define a list of expressions to be collected at each tracepoint.
2962 This is a useful way to ensure essential items are not overlooked,
2963 such as registers or a critical global variable.
2965 set disconnected-tracing
2966 show disconnected-tracing
2967 If set to 1, the target is instructed to continue tracing if it
2968 loses its connection to GDB. If 0, the target is to stop tracing
2971 set circular-trace-buffer
2972 show circular-trace-buffer
2973 If set to on, the target is instructed to use a circular trace buffer
2974 and discard the oldest trace frames instead of stopping the trace due
2975 to a full trace buffer. If set to off, the trace stops when the buffer
2976 fills up. Some targets may not support this.
2978 set script-extension off|soft|strict
2979 show script-extension
2980 If set to "off", the debugger does not perform any script language
2981 recognition, and all sourced files are assumed to be GDB scripts.
2982 If set to "soft" (the default), files are sourced according to
2983 filename extension, falling back to GDB scripts if the first
2985 If set to "strict", files are sourced according to filename extension.
2987 set ada trust-PAD-over-XVS on|off
2988 show ada trust-PAD-over-XVS
2989 If off, activate a workaround against a bug in the debugging information
2990 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2991 the GCC sources for more information about the GNAT encoding and
2992 PAD types in particular). It is always safe to set this option to
2993 off, but this introduces a slight performance penalty. The default
2996 * Python API Improvements
2998 ** GDB provides the new class gdb.LazyString. This is useful in
2999 some pretty-printing cases. The new method gdb.Value.lazy_string
3000 provides a simple way to create objects of this type.
3002 ** The fields returned by gdb.Type.fields now have an
3003 `is_base_class' attribute.
3005 ** The new method gdb.Type.range returns the range of an array type.
3007 ** The new method gdb.parse_and_eval can be used to parse and
3008 evaluate an expression.
3010 * New remote packets
3013 Define a trace state variable.
3016 Get the current value of a trace state variable.
3019 Set desired tracing behavior upon disconnection.
3022 Set the trace buffer to be linear or circular.
3025 Get data about the tracepoints currently in use.
3029 Process record now works correctly with hardware watchpoints.
3031 Multiple bug fixes have been made to the mips-irix port, making it
3032 much more reliable. In particular:
3033 - Debugging threaded applications is now possible again. Previously,
3034 GDB would hang while starting the program, or while waiting for
3035 the program to stop at a breakpoint.
3036 - Attaching to a running process no longer hangs.
3037 - An error occurring while loading a core file has been fixed.
3038 - Changing the value of the PC register now works again. This fixes
3039 problems observed when using the "jump" command, or when calling
3040 a function from GDB, or even when assigning a new value to $pc.
3041 - With the "finish" and "return" commands, the return value for functions
3042 returning a small array is now correctly printed.
3043 - It is now possible to break on shared library code which gets executed
3044 during a shared library init phase (code executed while executing
3045 their .init section). Previously, the breakpoint would have no effect.
3046 - GDB is now able to backtrace through the signal handler for
3047 non-threaded programs.
3049 PIE (Position Independent Executable) programs debugging is now supported.
3050 This includes debugging execution of PIC (Position Independent Code) shared
3051 libraries although for that, it should be possible to run such libraries as an
3054 *** Changes in GDB 7.0
3056 * GDB now has an interface for JIT compilation. Applications that
3057 dynamically generate code can create symbol files in memory and register
3058 them with GDB. For users, the feature should work transparently, and
3059 for JIT developers, the interface is documented in the GDB manual in the
3060 "JIT Compilation Interface" chapter.
3062 * Tracepoints may now be conditional. The syntax is as for
3063 breakpoints; either an "if" clause appended to the "trace" command,
3064 or the "condition" command is available. GDB sends the condition to
3065 the target for evaluation using the same bytecode format as is used
3066 for tracepoint actions.
3068 * The disassemble command now supports: an optional /r modifier, print the
3069 raw instructions in hex as well as in symbolic form, and an optional /m
3070 modifier to print mixed source+assembly.
3072 * Process record and replay
3074 In a architecture environment that supports ``process record and
3075 replay'', ``process record and replay'' target can record a log of
3076 the process execution, and replay it with both forward and reverse
3079 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3080 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3081 set execution-direction {forward|reverse}, for targets that support
3084 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3085 feature is available with a native GDB running on kernel version
3088 * GDB now has support for multi-byte and wide character sets on the
3089 target. Strings whose character type is wchar_t, char16_t, or
3090 char32_t are now correctly printed. GDB supports wide- and unicode-
3091 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3092 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3093 `printf'. This feature requires iconv to work properly; if your
3094 system does not have a working iconv, GDB can use GNU libiconv. See
3095 the installation instructions for more information.
3097 * GDB now supports automatic retrieval of shared library files from
3098 remote targets. To use this feature, specify a system root that begins
3099 with the `remote:' prefix, either via the `set sysroot' command or via
3100 the `--with-sysroot' configure-time option.
3102 * "info sharedlibrary" now takes an optional regex of libraries to show,
3103 and it now reports if a shared library has no debugging information.
3105 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3106 now complete on file names.
3108 * When completing in expressions, gdb will attempt to limit
3109 completions to allowable structure or union fields, where appropriate.
3110 For instance, consider:
3112 # struct example { int f1; double f2; };
3113 # struct example variable;
3116 If the user types TAB at the end of this command line, the available
3117 completions will be "f1" and "f2".
3119 * Inlined functions are now supported. They show up in backtraces, and
3120 the "step", "next", and "finish" commands handle them automatically.
3122 * GDB now supports the token-splicing (##) and stringification (#)
3123 operators when expanding macros. It also supports variable-arity
3126 * GDB now supports inspecting extra signal information, exported by
3127 the new $_siginfo convenience variable. The feature is currently
3128 implemented on linux ARM, i386 and amd64.
3130 * GDB can now display the VFP floating point registers and NEON vector
3131 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3132 can provide these registers (requires Linux 2.6.30 or later). Remote
3133 and simulator targets may also provide them.
3135 * New remote packets
3138 Search memory for a sequence of bytes.
3141 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3142 operation over reliable transport links. Use of this packet is
3143 controlled by the `set remote noack-packet' command.
3146 Kill the process with the specified process ID. Use this in preference
3147 to `k' when multiprocess protocol extensions are supported.
3150 Obtains additional operating system information
3154 Read or write additional signal information.
3156 * Removed remote protocol undocumented extension
3158 An undocumented extension to the remote protocol's `S' stop reply
3159 packet that permited the stub to pass a process id was removed.
3160 Remote servers should use the `T' stop reply packet instead.
3162 * GDB now supports multiple function calling conventions according to the
3163 DWARF-2 DW_AT_calling_convention function attribute.
3165 * The SH target utilizes the aforementioned change to distinguish between gcc
3166 and Renesas calling convention. It also adds the new CLI commands
3167 `set/show sh calling-convention'.
3169 * GDB can now read compressed debug sections, as produced by GNU gold
3170 with the --compress-debug-sections=zlib flag.
3172 * 64-bit core files are now supported on AIX.
3174 * Thread switching is now supported on Tru64.
3176 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3177 which will be allocated using malloc later in program execution.
3179 * The qXfer:libraries:read remote procotol packet now allows passing a
3180 list of section offsets.
3182 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3183 conditions handling signals delivered during attach or thread creation
3184 have also been fixed.
3186 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3187 From the user's standpoint, all unqualified instances of True and False
3188 are treated as the standard definitions, regardless of context.
3190 * GDB now parses C++ symbol and type names more flexibly. For
3193 template<typename T> class C { };
3196 GDB will now correctly handle all of:
3198 ptype C<char const *>
3199 ptype C<char const*>
3200 ptype C<const char *>
3201 ptype C<const char*>
3203 * New features in the GDB remote stub, gdbserver
3205 - The "--wrapper" command-line argument tells gdbserver to use a
3206 wrapper program to launch programs for debugging.
3208 - On PowerPC and S/390 targets, it is now possible to use a single
3209 gdbserver executable to debug both 32-bit and 64-bit programs.
3210 (This requires gdbserver itself to be built as a 64-bit executable.)
3212 - gdbserver uses the new noack protocol mode for TCP connections to
3213 reduce communications latency, if also supported and enabled in GDB.
3215 - Support for the sparc64-linux-gnu target is now included in
3218 - The amd64-linux build of gdbserver now supports debugging both
3219 32-bit and 64-bit programs.
3221 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3222 now support hardware watchpoints, and will use them automatically
3227 GDB now has support for scripting using Python. Whether this is
3228 available is determined at configure time.
3230 New GDB commands can now be written in Python.
3232 * Ada tasking support
3234 Ada tasks can now be inspected in GDB. The following commands have
3238 Print the list of Ada tasks.
3240 Print detailed information about task number N.
3242 Print the task number of the current task.
3244 Switch the context of debugging to task number N.
3246 * Support for user-defined prefixed commands. The "define" command can
3247 add new commands to existing prefixes, e.g. "target".
3249 * Multi-inferior, multi-process debugging.
3251 GDB now has generalized support for multi-inferior debugging. See
3252 "Debugging Multiple Inferiors" in the manual for more information.
3253 Although availability still depends on target support, the command
3254 set is more uniform now. The GNU/Linux specific multi-forks support
3255 has been migrated to this new framework. This implied some user
3256 visible changes; see "New commands" and also "Removed commands"
3259 * Target descriptions can now describe the target OS ABI. See the
3260 "Target Description Format" section in the user manual for more
3263 * Target descriptions can now describe "compatible" architectures
3264 to indicate that the target can execute applications for a different
3265 architecture in addition to those for the main target architecture.
3266 See the "Target Description Format" section in the user manual for
3269 * Multi-architecture debugging.
3271 GDB now includes general supports for debugging applications on
3272 hybrid systems that use more than one single processor architecture
3273 at the same time. Each such hybrid architecture still requires
3274 specific support to be added. The only hybrid architecture supported
3275 in this version of GDB is the Cell Broadband Engine.
3277 * GDB now supports integrated debugging of Cell/B.E. applications that
3278 use both the PPU and SPU architectures. To enable support for hybrid
3279 Cell/B.E. debugging, you need to configure GDB to support both the
3280 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3281 --enable-targets configure option.
3283 * Non-stop mode debugging.
3285 For some targets, GDB now supports an optional mode of operation in
3286 which you can examine stopped threads while other threads continue
3287 to execute freely. This is referred to as non-stop mode, with the
3288 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3289 section in the user manual for more information.
3291 To be able to support remote non-stop debugging, a remote stub needs
3292 to implement the non-stop mode remote protocol extensions, as
3293 described in the "Remote Non-Stop" section of the user manual. The
3294 GDB remote stub, gdbserver, has been adjusted to support these
3295 extensions on linux targets.
3297 * New commands (for set/show, see "New options" below)
3299 catch syscall [NAME(S) | NUMBER(S)]
3300 Catch system calls. Arguments, which should be names of system
3301 calls or their numbers, mean catch only those syscalls. Without
3302 arguments, every syscall will be caught. When the inferior issues
3303 any of the specified syscalls, GDB will stop and announce the system
3304 call, both when it is called and when its call returns. This
3305 feature is currently available with a native GDB running on the
3306 Linux Kernel, under the following architectures: x86, x86_64,
3307 PowerPC and PowerPC64.
3309 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3311 Search memory for a sequence of bytes.
3313 maint set python print-stack
3314 maint show python print-stack
3315 Show a stack trace when an error is encountered in a Python script.
3318 Invoke CODE by passing it to the Python interpreter.
3323 These allow macros to be defined, undefined, and listed
3327 Show operating system information about processes.
3330 List the inferiors currently under GDB's control.
3333 Switch focus to inferior number NUM.
3336 Detach from inferior number NUM.
3339 Kill inferior number NUM.
3343 set spu stop-on-load
3344 show spu stop-on-load
3345 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3347 set spu auto-flush-cache
3348 show spu auto-flush-cache
3349 Control whether to automatically flush the software-managed cache
3350 during Cell/B.E. debugging.
3352 set sh calling-convention
3353 show sh calling-convention
3354 Control the calling convention used when calling SH target functions.
3357 show debug timestamp
3358 Control display of timestamps with GDB debugging output.
3360 set disassemble-next-line
3361 show disassemble-next-line
3362 Control display of disassembled source lines or instructions when
3365 set remote noack-packet
3366 show remote noack-packet
3367 Set/show the use of remote protocol QStartNoAckMode packet. See above
3368 under "New remote packets."
3370 set remote query-attached-packet
3371 show remote query-attached-packet
3372 Control use of remote protocol `qAttached' (query-attached) packet.
3374 set remote read-siginfo-object
3375 show remote read-siginfo-object
3376 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3379 set remote write-siginfo-object
3380 show remote write-siginfo-object
3381 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3384 set remote reverse-continue
3385 show remote reverse-continue
3386 Control use of remote protocol 'bc' (reverse-continue) packet.
3388 set remote reverse-step
3389 show remote reverse-step
3390 Control use of remote protocol 'bs' (reverse-step) packet.
3392 set displaced-stepping
3393 show displaced-stepping
3394 Control displaced stepping mode. Displaced stepping is a way to
3395 single-step over breakpoints without removing them from the debuggee.
3396 Also known as "out-of-line single-stepping".
3399 show debug displaced
3400 Control display of debugging info for displaced stepping.
3402 maint set internal-error
3403 maint show internal-error
3404 Control what GDB does when an internal error is detected.
3406 maint set internal-warning
3407 maint show internal-warning
3408 Control what GDB does when an internal warning is detected.
3413 Use a wrapper program to launch programs for debugging.
3415 set multiple-symbols (all|ask|cancel)
3416 show multiple-symbols
3417 The value of this variable can be changed to adjust the debugger behavior
3418 when an expression or a breakpoint location contains an ambiguous symbol
3419 name (an overloaded function name, for instance).
3421 set breakpoint always-inserted
3422 show breakpoint always-inserted
3423 Keep breakpoints always inserted in the target, as opposed to inserting
3424 them when resuming the target, and removing them when the target stops.
3425 This option can improve debugger performance on slow remote targets.
3427 set arm fallback-mode (arm|thumb|auto)
3428 show arm fallback-mode
3429 set arm force-mode (arm|thumb|auto)
3431 These commands control how ARM GDB determines whether instructions
3432 are ARM or Thumb. The default for both settings is auto, which uses
3433 the current CPSR value for instructions without symbols; previous
3434 versions of GDB behaved as if "set arm fallback-mode arm".
3436 set disable-randomization
3437 show disable-randomization
3438 Standalone programs run with the virtual address space randomization enabled
3439 by default on some platforms. This option keeps the addresses stable across
3440 multiple debugging sessions.
3444 Control whether other threads are stopped or not when some thread hits
3449 Requests that asynchronous execution is enabled in the target, if available.
3450 In this case, it's possible to resume target in the background, and interact
3451 with GDB while the target is running. "show target-async" displays the
3452 current state of asynchronous execution of the target.
3454 set target-wide-charset
3455 show target-wide-charset
3456 The target-wide-charset is the name of the character set that GDB
3457 uses when printing characters whose type is wchar_t.
3459 set tcp auto-retry (on|off)
3461 set tcp connect-timeout
3462 show tcp connect-timeout
3463 These commands allow GDB to retry failed TCP connections to a remote stub
3464 with a specified timeout period; this is useful if the stub is launched
3465 in parallel with GDB but may not be ready to accept connections immediately.
3467 set libthread-db-search-path
3468 show libthread-db-search-path
3469 Control list of directories which GDB will search for appropriate
3472 set schedule-multiple (on|off)
3473 show schedule-multiple
3474 Allow GDB to resume all threads of all processes or only threads of
3475 the current process.
3479 Use more aggressive caching for accesses to the stack. This improves
3480 performance of remote debugging (particularly backtraces) without
3481 affecting correctness.
3483 set interactive-mode (on|off|auto)
3484 show interactive-mode
3485 Control whether GDB runs in interactive mode (on) or not (off).
3486 When in interactive mode, GDB waits for the user to answer all
3487 queries. Otherwise, GDB does not wait and assumes the default
3488 answer. When set to auto (the default), GDB determines which
3489 mode to use based on the stdin settings.
3494 For program forks, this is replaced by the new more generic `info
3495 inferiors' command. To list checkpoints, you can still use the
3496 `info checkpoints' command, which was an alias for the `info forks'
3500 Replaced by the new `inferior' command. To switch between
3501 checkpoints, you can still use the `restart' command, which was an
3502 alias for the `fork' command.
3505 This is removed, since some targets don't have a notion of
3506 processes. To switch between processes, you can still use the
3507 `inferior' command using GDB's own inferior number.
3510 For program forks, this is replaced by the new more generic `kill
3511 inferior' command. To delete a checkpoint, you can still use the
3512 `delete checkpoint' command, which was an alias for the `delete
3516 For program forks, this is replaced by the new more generic `detach
3517 inferior' command. To detach a checkpoint, you can still use the
3518 `detach checkpoint' command, which was an alias for the `detach
3521 * New native configurations
3523 x86/x86_64 Darwin i[34567]86-*-darwin*
3525 x86_64 MinGW x86_64-*-mingw*
3529 Lattice Mico32 lm32-*
3530 x86 DICOS i[34567]86-*-dicos*
3531 x86_64 DICOS x86_64-*-dicos*
3534 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3535 (mingw32ce) debugging.
3541 These commands were actually not implemented on any target.
3543 *** Changes in GDB 6.8
3545 * New native configurations
3547 NetBSD/hppa hppa*-*netbsd*
3548 Xtensa GNU/Linux xtensa*-*-linux*
3552 NetBSD/hppa hppa*-*-netbsd*
3553 Xtensa GNU/Lunux xtensa*-*-linux*
3555 * Change in command line behavior -- corefiles vs. process ids.
3557 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3558 attaching to process NUMBER fails, GDB no longer attempts to open a
3559 core file named NUMBER. Attaching to a program using the -c option
3560 is no longer supported. Instead, use the '-p' or '--pid' options.
3562 * GDB can now be built as a native debugger for debugging Windows x86
3563 (mingw32) Portable Executable (PE) programs.
3565 * Pending breakpoints no longer change their number when their address
3568 * GDB now supports breakpoints with multiple locations,
3569 including breakpoints on C++ constructors, inside C++ templates,
3570 and in inlined functions.
3572 * GDB's ability to debug optimized code has been improved. GDB more
3573 accurately identifies function bodies and lexical blocks that occupy
3574 more than one contiguous range of addresses.
3576 * Target descriptions can now describe registers for PowerPC.
3578 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3579 registers on PowerPC targets.
3581 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3582 targets even when the libthread_db library is not available.
3584 * The GDB remote stub, gdbserver, now supports the new file transfer
3585 commands (remote put, remote get, and remote delete).
3587 * The GDB remote stub, gdbserver, now supports run and attach in
3588 extended-remote mode.
3590 * hppa*64*-*-hpux11* target broken
3591 The debugger is unable to start a program and fails with the following
3592 error: "Error trying to get information about dynamic linker".
3593 The gdb-6.7 release is also affected.
3595 * GDB now supports the --enable-targets= configure option to allow
3596 building a single GDB executable that supports multiple remote
3597 target architectures.
3599 * GDB now supports debugging C and C++ programs which use the
3600 Decimal Floating Point extension. In addition, the PowerPC target
3601 now has a set of pseudo-registers to inspect decimal float values
3602 stored in two consecutive float registers.
3604 * The -break-insert MI command can optionally create pending
3607 * Improved support for debugging Ada
3608 Many improvements to the Ada language support have been made. These
3610 - Better support for Ada2005 interface types
3611 - Improved handling of arrays and slices in general
3612 - Better support for Taft-amendment types
3613 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3615 - Improved command completion in Ada
3618 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3623 set print frame-arguments (all|scalars|none)
3624 show print frame-arguments
3625 The value of this variable can be changed to control which argument
3626 values should be printed by the debugger when displaying a frame.
3631 Transfer files to and from a remote target, and delete remote files.
3638 Transfer files to and from a remote target, and delete remote files.
3640 * New remote packets
3647 Open, close, read, write, and delete files on the remote system.
3650 Attach to an existing process on the remote system, in extended-remote
3654 Run a new process on the remote system, in extended-remote mode.
3656 *** Changes in GDB 6.7
3658 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3659 bfd, libiberty and opcodes, as revealed by static analysis donated by
3660 Coverity, Inc. (http://scan.coverity.com).
3662 * When looking up multiply-defined global symbols, GDB will now prefer the
3663 symbol definition in the current shared library if it was built using the
3664 -Bsymbolic linker option.
3666 * When the Text User Interface (TUI) is not configured, GDB will now
3667 recognize the -tui command-line option and print a message that the TUI
3670 * The GDB remote stub, gdbserver, now has lower overhead for high
3671 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3673 * GDB for MIPS targets now autodetects whether a remote target provides
3674 32-bit or 64-bit register values.
3676 * Support for C++ member pointers has been improved.
3678 * GDB now understands XML target descriptions, which specify the
3679 target's overall architecture. GDB can read a description from
3680 a local file or over the remote serial protocol.
3682 * Vectors of single-byte data use a new integer type which is not
3683 automatically displayed as character or string data.
3685 * The /s format now works with the print command. It displays
3686 arrays of single-byte integers and pointers to single-byte integers
3689 * Target descriptions can now describe target-specific registers,
3690 for architectures which have implemented the support (currently
3691 only ARM, M68K, and MIPS).
3693 * GDB and the GDB remote stub, gdbserver, now support the XScale
3696 * The GDB remote stub, gdbserver, has been updated to support
3697 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3698 has been rewritten to use the standard GDB remote protocol.
3700 * GDB can now step into C++ functions which are called through thunks.
3702 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3704 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3705 layout. It also supports a TextSeg= and DataSeg= response when only
3706 segment base addresses (rather than offsets) are available.
3708 * The /i format now outputs any trailing branch delay slot instructions
3709 immediately following the last instruction within the count specified.
3711 * The GDB remote protocol "T" stop reply packet now supports a
3712 "library" response. Combined with the new "qXfer:libraries:read"
3713 packet, this response allows GDB to debug shared libraries on targets
3714 where the operating system manages the list of loaded libraries (e.g.
3715 Windows and SymbianOS).
3717 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3718 (DLLs) on Windows and Windows CE targets.
3720 * GDB now supports a faster verification that a .debug file matches its binary
3721 according to its build-id signature, if the signature is present.
3727 Enable or disable hardware flow control (RTS/CTS) on the serial port
3728 when debugging using remote targets.
3730 set mem inaccessible-by-default
3731 show mem inaccessible-by-default
3732 If the target supplies a memory map, for instance via the remote
3733 protocol's "qXfer:memory-map:read" packet, setting this variable
3734 prevents GDB from accessing memory outside the memory map. This
3735 is useful for targets with memory mapped registers or which react
3736 badly to accesses of unmapped address space.
3738 set breakpoint auto-hw
3739 show breakpoint auto-hw
3740 If the target supplies a memory map, for instance via the remote
3741 protocol's "qXfer:memory-map:read" packet, setting this variable
3742 lets GDB use hardware breakpoints automatically for memory regions
3743 where it can not use software breakpoints. This covers both the
3744 "break" command and internal breakpoints used for other commands
3745 including "next" and "finish".
3748 catch exception unhandled
3749 Stop the program execution when Ada exceptions are raised.
3752 Stop the program execution when an Ada assertion failed.
3756 Set an alternate system root for target files. This is a more
3757 general version of "set solib-absolute-prefix", which is now
3758 an alias to "set sysroot".
3761 Provide extended SPU facility status information. This set of
3762 commands is available only when debugging the Cell/B.E. SPU
3765 * New native configurations
3767 OpenBSD/sh sh*-*openbsd*
3770 unset tdesc filename
3772 Use the specified local file as an XML target description, and do
3773 not query the target for its built-in description.
3777 OpenBSD/sh sh*-*-openbsd*
3778 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3779 Toshiba Media Processor mep-elf
3781 * New remote packets
3784 Ignore the specified signals; pass them directly to the debugged program
3785 without stopping other threads or reporting them to GDB.
3787 qXfer:features:read:
3788 Read an XML target description from the target, which describes its
3793 Read or write contents of an spufs file on the target system. These
3794 packets are available only on the Cell/B.E. SPU architecture.
3796 qXfer:libraries:read:
3797 Report the loaded shared libraries. Combined with new "T" packet
3798 response, this packet allows GDB to debug shared libraries on
3799 targets where the operating system manages the list of loaded
3800 libraries (e.g. Windows and SymbianOS).
3804 Support for these obsolete configurations has been removed.
3812 i[34567]86-*-lynxos*
3813 i[34567]86-*-netware*
3814 i[34567]86-*-sco3.2v5*
3815 i[34567]86-*-sco3.2v4*
3817 i[34567]86-*-sysv4.2*
3820 i[34567]86-*-unixware2*
3821 i[34567]86-*-unixware*
3830 * Other removed features
3837 Various m68k-only ROM monitors.
3844 Various Renesas ROM monitors and debugging interfaces for SH and
3849 Support for a Macraigor serial interface to on-chip debugging.
3850 GDB does not directly support the newer parallel or USB
3855 A debug information format. The predecessor to DWARF 2 and
3856 DWARF 3, which are still supported.
3858 Support for the HP aCC compiler on HP-UX/PA-RISC
3860 SOM-encapsulated symbolic debugging information, automatic
3861 invocation of pxdb, and the aCC custom C++ ABI. This does not
3862 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3863 with aCC can still be debugged on an assembly level.
3865 MIPS ".pdr" sections
3867 A MIPS-specific format used to describe stack frame layout
3868 in debugging information.
3872 GDB could work with an older version of Guile to debug
3873 the interpreter and Scheme programs running in it.
3875 set mips stack-arg-size
3876 set mips saved-gpreg-size
3878 Use "set mips abi" to control parameter passing for MIPS.
3880 *** Changes in GDB 6.6
3885 Cell Broadband Engine SPU spu-elf
3887 * GDB can now be configured as a cross-debugger targeting native Windows
3888 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3889 running on a Windows system over TCP/IP to debug Windows programs.
3891 * The GDB remote stub, gdbserver, has been updated to support Windows and
3892 Cygwin debugging. Both single-threaded and multi-threaded programs are
3895 * The "set trust-readonly-sections" command works again. This command was
3896 broken in GDB 6.3, 6.4, and 6.5.
3898 * The "load" command now supports writing to flash memory, if the remote
3899 stub provides the required support.
3901 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3902 longer requires symbolic debug information (e.g. DWARF-2).
3907 unset substitute-path
3908 show substitute-path
3909 Manage a list of substitution rules that GDB uses to rewrite the name
3910 of the directories where the sources are located. This can be useful
3911 for instance when the sources were moved to a different location
3912 between compilation and debugging.
3916 Print each CLI command as it is executed. Each command is prefixed with
3917 a number of `+' symbols representing the nesting depth.
3918 The source command now has a `-v' option to enable the same feature.
3922 The ARM Demon monitor support (RDP protocol, "target rdp").
3924 Kernel Object Display, an embedded debugging feature which only worked with
3925 an obsolete version of Cisco IOS.
3927 The 'set download-write-size' and 'show download-write-size' commands.
3929 * New remote packets
3932 Tell a stub about GDB client features, and request remote target features.
3933 The first feature implemented is PacketSize, which allows the target to
3934 specify the size of packets it can handle - to minimize the number of
3935 packets required and improve performance when connected to a remote
3939 Fetch an OS auxilliary vector from the remote stub. This packet is a
3940 more efficient replacement for qPart:auxv:read.
3942 qXfer:memory-map:read:
3943 Fetch a memory map from the remote stub, including information about
3944 RAM, ROM, and flash memory devices.
3949 Erase and program a flash memory device.
3951 * Removed remote packets
3954 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3955 used it, and only gdbserver implemented it.
3957 *** Changes in GDB 6.5
3961 Renesas M32C/M16C m32c-elf
3963 Morpho Technologies ms1 ms1-elf
3967 init-if-undefined Initialize a convenience variable, but
3968 only if it doesn't already have a value.
3970 The following commands are presently only implemented for native GNU/Linux:
3972 checkpoint Save a snapshot of the program state.
3974 restart <n> Return the program state to a
3975 previously saved state.
3977 info checkpoints List currently saved checkpoints.
3979 delete-checkpoint <n> Delete a previously saved checkpoint.
3981 set|show detach-on-fork Tell gdb whether to detach from a newly
3982 forked process, or to keep debugging it.
3984 info forks List forks of the user program that
3985 are available to be debugged.
3987 fork <n> Switch to debugging one of several
3988 forks of the user program that are
3989 available to be debugged.
3991 delete-fork <n> Delete a fork from the list of forks
3992 that are available to be debugged (and
3993 kill the forked process).
3995 detach-fork <n> Delete a fork from the list of forks
3996 that are available to be debugged (and
3997 allow the process to continue).
4001 Morpho Technologies ms2 ms1-elf
4003 * Improved Windows host support
4005 GDB now builds as a cross debugger hosted on i686-mingw32, including
4006 native console support, and remote communications using either
4007 network sockets or serial ports.
4009 * Improved Modula-2 language support
4011 GDB can now print most types in the Modula-2 syntax. This includes:
4012 basic types, set types, record types, enumerated types, range types,
4013 pointer types and ARRAY types. Procedure var parameters are correctly
4014 printed and hexadecimal addresses and character constants are also
4015 written in the Modula-2 syntax. Best results can be obtained by using
4016 GNU Modula-2 together with the -gdwarf-2 command line option.
4020 The ARM rdi-share module.
4022 The Netware NLM debug server.
4024 *** Changes in GDB 6.4
4026 * New native configurations
4028 OpenBSD/arm arm*-*-openbsd*
4029 OpenBSD/mips64 mips64-*-openbsd*
4033 Morpho Technologies ms1 ms1-elf
4035 * New command line options
4037 --batch-silent As for --batch, but totally silent.
4038 --return-child-result The debugger will exist with the same value
4039 the child (debugged) program exited with.
4040 --eval-command COMMAND, -ex COMMAND
4041 Execute a single GDB CLI command. This may be
4042 specified multiple times and in conjunction
4043 with the --command (-x) option.
4045 * Deprecated commands removed
4047 The following commands, that were deprecated in 2000, have been
4051 set|show arm disassembly-flavor set|show arm disassembler
4052 othernames set arm disassembler
4053 set|show remotedebug set|show debug remote
4054 set|show archdebug set|show debug arch
4055 set|show eventdebug set|show debug event
4058 * New BSD user-level threads support
4060 It is now possible to debug programs using the user-level threads
4061 library on OpenBSD and FreeBSD. Currently supported (target)
4064 FreeBSD/amd64 x86_64-*-freebsd*
4065 FreeBSD/i386 i386-*-freebsd*
4066 OpenBSD/i386 i386-*-openbsd*
4068 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4069 are not yet supported.
4071 * New support for Matsushita MN10300 w/sim added
4072 (Work in progress). mn10300-elf.
4074 * REMOVED configurations and files
4076 VxWorks and the XDR protocol *-*-vxworks
4077 Motorola MCORE mcore-*-*
4078 National Semiconductor NS32000 ns32k-*-*
4080 * New "set print array-indexes" command
4082 After turning this setting "on", GDB prints the index of each element
4083 when displaying arrays. The default is "off" to preserve the previous
4086 * VAX floating point support
4088 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4090 * User-defined command support
4092 In addition to using $arg0..$arg9 for argument passing, it is now possible
4093 to use $argc to determine now many arguments have been passed. See the
4094 section on user-defined commands in the user manual for more information.
4096 *** Changes in GDB 6.3:
4098 * New command line option
4100 GDB now accepts -l followed by a number to set the timeout for remote
4103 * GDB works with GCC -feliminate-dwarf2-dups
4105 GDB now supports a more compact representation of DWARF-2 debug
4106 information using DW_FORM_ref_addr references. These are produced
4107 by GCC with the option -feliminate-dwarf2-dups and also by some
4108 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4109 to use -feliminate-dwarf2-dups.
4111 * Internationalization
4113 When supported by the host system, GDB will be built with
4114 internationalization (libintl). The task of marking up the sources is
4115 continued, we're looking forward to our first translation.
4119 Initial support for debugging programs compiled with the GNAT
4120 implementation of the Ada programming language has been integrated
4121 into GDB. In this release, support is limited to expression evaluation.
4123 * New native configurations
4125 GNU/Linux/m32r m32r-*-linux-gnu
4129 GDB's remote protocol now includes support for the 'p' packet. This
4130 packet is used to fetch individual registers from a remote inferior.
4132 * END-OF-LIFE registers[] compatibility module
4134 GDB's internal register infrastructure has been completely rewritten.
4135 The new infrastructure making possible the implementation of key new
4136 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4139 GDB 6.3 will be the last release to include the the registers[]
4140 compatibility module that allowed out-of-date configurations to
4141 continue to work. This change directly impacts the following
4151 powerpc bdm protocol
4153 Unless there is activity to revive these configurations, they will be
4154 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4156 * OBSOLETE configurations and files
4158 Configurations that have been declared obsolete in this release have
4159 been commented out. Unless there is activity to revive these
4160 configurations, the next release of GDB will have their sources
4161 permanently REMOVED.
4170 *** Changes in GDB 6.2.1:
4172 * MIPS `break main; run' gave an heuristic-fence-post warning
4174 When attempting to run even a simple program, a warning about
4175 heuristic-fence-post being hit would be reported. This problem has
4178 * MIPS IRIX 'long double' crashed GDB
4180 When examining a long double variable, GDB would get a segmentation
4181 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4182 IRIX long double values).
4186 A bug in the VAX stack code was causing problems with the "next"
4187 command. This problem has been fixed.
4189 *** Changes in GDB 6.2:
4191 * Fix for ``many threads''
4193 On GNU/Linux systems that use the NPTL threads library, a program
4194 rapidly creating and deleting threads would confuse GDB leading to the
4197 ptrace: No such process.
4198 thread_db_get_info: cannot get thread info: generic error
4200 This problem has been fixed.
4202 * "-async" and "-noasync" options removed.
4204 Support for the broken "-noasync" option has been removed (it caused
4207 * New ``start'' command.
4209 This command runs the program until the begining of the main procedure.
4211 * New BSD Kernel Data Access Library (libkvm) interface
4213 Using ``target kvm'' it is now possible to debug kernel core dumps and
4214 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4215 platforms. Currently supported (native-only) configurations are:
4217 FreeBSD/amd64 x86_64-*-freebsd*
4218 FreeBSD/i386 i?86-*-freebsd*
4219 NetBSD/i386 i?86-*-netbsd*
4220 NetBSD/m68k m68*-*-netbsd*
4221 NetBSD/sparc sparc-*-netbsd*
4222 OpenBSD/amd64 x86_64-*-openbsd*
4223 OpenBSD/i386 i?86-*-openbsd*
4224 OpenBSD/m68k m68*-openbsd*
4225 OpenBSD/sparc sparc-*-openbsd*
4227 * Signal trampoline code overhauled
4229 Many generic problems with GDB's signal handling code have been fixed.
4230 These include: backtraces through non-contiguous stacks; recognition
4231 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4232 call; backtrace through a signal trampoline; step into and out of
4233 signal handlers; and single-stepping in the signal trampoline.
4235 Please note that kernel bugs are a limiting factor here. These
4236 features have been shown to work on an s390 GNU/Linux system that
4237 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4239 * Cygwin support for DWARF 2 added.
4241 * New native configurations
4243 GNU/Linux/hppa hppa*-*-linux*
4244 OpenBSD/hppa hppa*-*-openbsd*
4245 OpenBSD/m68k m68*-*-openbsd*
4246 OpenBSD/m88k m88*-*-openbsd*
4247 OpenBSD/powerpc powerpc-*-openbsd*
4248 NetBSD/vax vax-*-netbsd*
4249 OpenBSD/vax vax-*-openbsd*
4251 * END-OF-LIFE frame compatibility module
4253 GDB's internal frame infrastructure has been completely rewritten.
4254 The new infrastructure making it possible to support key new features
4255 including DWARF 2 Call Frame Information. To aid in the task of
4256 migrating old configurations to this new infrastructure, a
4257 compatibility module, that allowed old configurations to continue to
4258 work, was also included.
4260 GDB 6.2 will be the last release to include this frame compatibility
4261 module. This change directly impacts the following configurations:
4271 Unless there is activity to revive these configurations, they will be
4272 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4274 * REMOVED configurations and files
4276 Sun 3, running SunOS 3 m68*-*-sunos3*
4277 Sun 3, running SunOS 4 m68*-*-sunos4*
4278 Sun 2, running SunOS 3 m68000-*-sunos3*
4279 Sun 2, running SunOS 4 m68000-*-sunos4*
4280 Motorola 680x0 running LynxOS m68*-*-lynxos*
4281 AT&T 3b1/Unix pc m68*-att-*
4282 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4283 decstation mips-dec-* mips-little-*
4284 riscos mips-*-riscos* mips-*-sysv*
4285 sonymips mips-sony-*
4286 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4288 *** Changes in GDB 6.1.1:
4290 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4292 The TUI (Text-mode User Interface) is now built as part of a default
4293 GDB configuration. It is enabled by either selecting the TUI with the
4294 command line option "-i=tui" or by running the separate "gdbtui"
4295 program. For more information on the TUI, see the manual "Debugging
4298 * Pending breakpoint support (also included in GDB 6.1)
4300 Support has been added to allow you to specify breakpoints in shared
4301 libraries that have not yet been loaded. If a breakpoint location
4302 cannot be found, and the "breakpoint pending" option is set to auto,
4303 GDB queries you if you wish to make the breakpoint pending on a future
4304 shared-library load. If and when GDB resolves the breakpoint symbol,
4305 the pending breakpoint is removed as one or more regular breakpoints
4308 Pending breakpoints are very useful for GCJ Java debugging.
4310 * Fixed ISO-C build problems
4312 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4313 non ISO-C code that stopped them being built using a more strict ISO-C
4314 compiler (e.g., IBM's C compiler).
4316 * Fixed build problem on IRIX 5
4318 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4319 wasn't able to compile compile on an IRIX 5 system.
4321 * Added execute permission to gdb/gdbserver/configure
4323 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4324 permission. This bug would cause configure to fail on a number of
4325 systems (Solaris, IRIX). Ref: server/519.
4327 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4329 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4330 has been updated to use constant array sizes.
4332 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4334 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4335 its generated DWARF Call Frame Info. This encoding was causing GDB to
4336 panic, that panic has been fixed. Ref: gdb/1628.
4338 * Fixed a problem when examining parameters in shared library code.
4340 When examining parameters in optimized shared library code generated
4341 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4342 not available''. GDB now correctly displays the variable's value.
4344 *** Changes in GDB 6.1:
4346 * Removed --with-mmalloc
4348 Support for the mmalloc memory manager has been removed, as it
4349 conflicted with the internal gdb byte cache.
4351 * Changes in AMD64 configurations
4353 The AMD64 target now includes the %cs and %ss registers. As a result
4354 the AMD64 remote protocol has changed; this affects the floating-point
4355 and SSE registers. If you rely on those registers for your debugging,
4356 you should upgrade gdbserver on the remote side.
4358 * Revised SPARC target
4360 The SPARC target has been completely revised, incorporating the
4361 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4362 support for LynxOS and SunOS 4 has been dropped. Calling functions
4363 from within GDB on operating systems with a non-executable stack
4364 (Solaris, OpenBSD) now works.
4368 GDB has a new C++ demangler which does a better job on the mangled
4369 names generated by current versions of g++. It also runs faster, so
4370 with this and other changes gdb should now start faster on large C++
4373 * DWARF 2 Location Expressions
4375 GDB support for location expressions has been extended to support function
4376 arguments and frame bases. Older versions of GDB could crash when they
4379 * C++ nested types and namespaces
4381 GDB's support for nested types and namespaces in C++ has been
4382 improved, especially if you use the DWARF 2 debugging format. (This
4383 is the default for recent versions of GCC on most platforms.)
4384 Specifically, if you have a class "Inner" defined within a class or
4385 namespace "Outer", then GDB realizes that the class's name is
4386 "Outer::Inner", not simply "Inner". This should greatly reduce the
4387 frequency of complaints about not finding RTTI symbols. In addition,
4388 if you are stopped at inside of a function defined within a namespace,
4389 GDB modifies its name lookup accordingly.
4391 * New native configurations
4393 NetBSD/amd64 x86_64-*-netbsd*
4394 OpenBSD/amd64 x86_64-*-openbsd*
4395 OpenBSD/alpha alpha*-*-openbsd*
4396 OpenBSD/sparc sparc-*-openbsd*
4397 OpenBSD/sparc64 sparc64-*-openbsd*
4399 * New debugging protocols
4401 M32R with SDI protocol m32r-*-elf*
4403 * "set prompt-escape-char" command deleted.
4405 The command "set prompt-escape-char" has been deleted. This command,
4406 and its very obscure effet on GDB's prompt, was never documented,
4407 tested, nor mentioned in the NEWS file.
4409 * OBSOLETE configurations and files
4411 Configurations that have been declared obsolete in this release have
4412 been commented out. Unless there is activity to revive these
4413 configurations, the next release of GDB will have their sources
4414 permanently REMOVED.
4416 Sun 3, running SunOS 3 m68*-*-sunos3*
4417 Sun 3, running SunOS 4 m68*-*-sunos4*
4418 Sun 2, running SunOS 3 m68000-*-sunos3*
4419 Sun 2, running SunOS 4 m68000-*-sunos4*
4420 Motorola 680x0 running LynxOS m68*-*-lynxos*
4421 AT&T 3b1/Unix pc m68*-att-*
4422 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4423 decstation mips-dec-* mips-little-*
4424 riscos mips-*-riscos* mips-*-sysv*
4425 sonymips mips-sony-*
4426 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4428 * REMOVED configurations and files
4430 SGI Irix-4.x mips-sgi-irix4 or iris4
4431 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4432 Z8000 simulator z8k-zilog-none or z8ksim
4433 Matsushita MN10200 w/simulator mn10200-*-*
4434 H8/500 simulator h8500-hitachi-hms or h8500hms
4435 HP/PA running BSD hppa*-*-bsd*
4436 HP/PA running OSF/1 hppa*-*-osf*
4437 HP/PA Pro target hppa*-*-pro*
4438 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4439 386BSD i[3456]86-*-bsd*
4440 Sequent family i[3456]86-sequent-sysv4*
4441 i[3456]86-sequent-sysv*
4442 i[3456]86-sequent-bsd*
4443 SPARC running LynxOS sparc-*-lynxos*
4444 SPARC running SunOS 4 sparc-*-sunos4*
4445 Tsqware Sparclet sparclet-*-*
4446 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4448 *** Changes in GDB 6.0:
4452 Support for debugging the Objective-C programming language has been
4453 integrated into GDB.
4455 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4457 DWARF 2's Call Frame Information makes available compiler generated
4458 information that more exactly describes the program's run-time stack.
4459 By using this information, GDB is able to provide more robust stack
4462 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4463 have been updated to use a new backtrace mechanism which includes
4464 DWARF 2 CFI support.
4468 GDB's remote protocol has been extended to include support for hosted
4469 file I/O (where the remote target uses GDB's file system). See GDB's
4470 remote protocol documentation for details.
4472 * All targets using the new architecture framework.
4474 All of GDB's targets have been updated to use the new internal
4475 architecture framework. The way is now open for future GDB releases
4476 to include cross-architecture native debugging support (i386 on amd64,
4479 * GNU/Linux's Thread Local Storage (TLS)
4481 GDB now includes support for for the GNU/Linux implementation of
4482 per-thread variables.
4484 * GNU/Linux's Native POSIX Thread Library (NPTL)
4486 GDB's thread code has been updated to work with either the new
4487 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4489 * Separate debug info.
4491 GDB, in conjunction with BINUTILS, now supports a mechanism for
4492 automatically loading debug information from a separate file. Instead
4493 of shipping full debug and non-debug versions of system libraries,
4494 system integrators can now instead ship just the stripped libraries
4495 and optional debug files.
4497 * DWARF 2 Location Expressions
4499 DWARF 2 Location Expressions allow the compiler to more completely
4500 describe the location of variables (even in optimized code) to the
4503 GDB now includes preliminary support for location expressions (support
4504 for DW_OP_piece is still missing).
4508 A number of long standing bugs that caused GDB to die while starting a
4509 Java application have been fixed. GDB's Java support is now
4510 considered "useable".
4512 * GNU/Linux support for fork, vfork, and exec.
4514 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4515 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4518 * GDB supports logging output to a file
4520 There are two new commands, "set logging" and "show logging", which can be
4521 used to capture GDB's output to a file.
4523 * The meaning of "detach" has changed for gdbserver
4525 The "detach" command will now resume the application, as documented. To
4526 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4529 * d10v, m68hc11 `regs' command deprecated
4531 The `info registers' command has been updated so that it displays the
4532 registers using a format identical to the old `regs' command.
4536 A new command, "maint set profile on/off", has been added. This command can
4537 be used to enable or disable profiling while running GDB, to profile a
4538 session or a set of commands. In addition there is a new configure switch,
4539 "--enable-profiling", which will cause GDB to be compiled with profiling
4540 data, for more informative profiling results.
4542 * Default MI syntax changed to "mi2".
4544 The default MI (machine interface) syntax, enabled by the command line
4545 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4546 "mi1", can be enabled by specifying the option "-i=mi1".
4548 Support for the original "mi0" syntax (included in GDB 5.0) has been
4551 Fix for gdb/192: removed extraneous space when displaying frame level.
4552 Fix for gdb/672: update changelist is now output in mi list format.
4553 Fix for gdb/702: a -var-assign that updates the value now shows up
4554 in a subsequent -var-update.
4556 * New native configurations.
4558 FreeBSD/amd64 x86_64-*-freebsd*
4560 * Multi-arched targets.
4562 HP/PA HPUX11 hppa*-*-hpux*
4563 Renesas M32R/D w/simulator m32r-*-elf*
4565 * OBSOLETE configurations and files
4567 Configurations that have been declared obsolete in this release have
4568 been commented out. Unless there is activity to revive these
4569 configurations, the next release of GDB will have their sources
4570 permanently REMOVED.
4572 Z8000 simulator z8k-zilog-none or z8ksim
4573 Matsushita MN10200 w/simulator mn10200-*-*
4574 H8/500 simulator h8500-hitachi-hms or h8500hms
4575 HP/PA running BSD hppa*-*-bsd*
4576 HP/PA running OSF/1 hppa*-*-osf*
4577 HP/PA Pro target hppa*-*-pro*
4578 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4579 Sequent family i[3456]86-sequent-sysv4*
4580 i[3456]86-sequent-sysv*
4581 i[3456]86-sequent-bsd*
4582 Tsqware Sparclet sparclet-*-*
4583 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4585 * REMOVED configurations and files
4588 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4589 IBM AIX PS/2 i[3456]86-*-aix
4590 i386 running Mach 3.0 i[3456]86-*-mach3*
4591 i386 running Mach i[3456]86-*-mach*
4592 i386 running OSF/1 i[3456]86-*osf1mk*
4593 HP/Apollo 68k Family m68*-apollo*-sysv*,
4595 m68*-hp-bsd*, m68*-hp-hpux*
4596 Argonaut Risc Chip (ARC) arc-*-*
4597 Mitsubishi D30V d30v-*-*
4598 Fujitsu FR30 fr30-*-elf*
4599 OS/9000 i[34]86-*-os9k
4600 I960 with MON960 i960-*-coff
4602 * MIPS $fp behavior changed
4604 The convenience variable $fp, for the MIPS, now consistently returns
4605 the address of the current frame's base. Previously, depending on the
4606 context, $fp could refer to either $sp or the current frame's base
4607 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4608 The GNU Source-Level Debugger''.
4610 *** Changes in GDB 5.3:
4612 * GNU/Linux shared library multi-threaded performance improved.
4614 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4615 `/proc', in preference to `ptrace' for memory reads. This may result
4616 in an improvement in the start-up time of multi-threaded, shared
4617 library applications when run under GDB. One GDB user writes: ``loads
4618 shared libs like mad''.
4620 * ``gdbserver'' now supports multi-threaded applications on some targets
4622 Support for debugging multi-threaded applications which use
4623 the GNU/Linux LinuxThreads package has been added for
4624 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4625 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4627 * GDB now supports C/C++ preprocessor macros.
4629 GDB now expands preprocessor macro invocations in C/C++ expressions,
4630 and provides various commands for showing macro definitions and how
4633 The new command `macro expand EXPRESSION' expands any macro
4634 invocations in expression, and shows the result.
4636 The new command `show macro MACRO-NAME' shows the definition of the
4637 macro named MACRO-NAME, and where it was defined.
4639 Most compilers don't include information about macros in the debugging
4640 information by default. In GCC 3.1, for example, you need to compile
4641 your program with the options `-gdwarf-2 -g3'. If the macro
4642 information is present in the executable, GDB will read it.
4644 * Multi-arched targets.
4646 DEC Alpha (partial) alpha*-*-*
4647 DEC VAX (partial) vax-*-*
4649 National Semiconductor NS32000 (partial) ns32k-*-*
4650 Motorola 68000 (partial) m68k-*-*
4651 Motorola MCORE mcore-*-*
4655 Fujitsu FRV architecture added by Red Hat frv*-*-*
4658 * New native configurations
4660 Alpha NetBSD alpha*-*-netbsd*
4661 SH NetBSD sh*-*-netbsdelf*
4662 MIPS NetBSD mips*-*-netbsd*
4663 UltraSPARC NetBSD sparc64-*-netbsd*
4665 * OBSOLETE configurations and files
4667 Configurations that have been declared obsolete in this release have
4668 been commented out. Unless there is activity to revive these
4669 configurations, the next release of GDB will have their sources
4670 permanently REMOVED.
4672 Mitsubishi D30V d30v-*-*
4673 OS/9000 i[34]86-*-os9k
4674 IBM AIX PS/2 i[3456]86-*-aix
4675 Fujitsu FR30 fr30-*-elf*
4676 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4677 Argonaut Risc Chip (ARC) arc-*-*
4678 i386 running Mach 3.0 i[3456]86-*-mach3*
4679 i386 running Mach i[3456]86-*-mach*
4680 i386 running OSF/1 i[3456]86-*osf1mk*
4681 HP/Apollo 68k Family m68*-apollo*-sysv*,
4683 m68*-hp-bsd*, m68*-hp-hpux*
4684 I960 with MON960 i960-*-coff
4686 * OBSOLETE languages
4688 CHILL, a Pascal like language used by telecommunications companies.
4690 * REMOVED configurations and files
4692 AMD 29k family via UDI a29k-amd-udi, udi29k
4693 A29K VxWorks a29k-*-vxworks
4694 AMD 29000 embedded, using EBMON a29k-none-none
4695 AMD 29000 embedded with COFF a29k-none-coff
4696 AMD 29000 embedded with a.out a29k-none-aout
4698 testsuite/gdb.hp/gdb.threads-hp/ directory
4700 * New command "set max-user-call-depth <nnn>"
4702 This command allows the user to limit the call depth of user-defined
4703 commands. The default is 1024.
4705 * Changes in FreeBSD/i386 native debugging.
4707 Support for the "generate-core-file" has been added.
4709 * New commands "dump", "append", and "restore".
4711 These commands allow data to be copied from target memory
4712 to a bfd-format or binary file (dump and append), and back
4713 from a file into memory (restore).
4715 * Improved "next/step" support on multi-processor Alpha Tru64.
4717 The previous single-step mechanism could cause unpredictable problems,
4718 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4719 of a software single-step mechanism prevents this.
4721 *** Changes in GDB 5.2.1:
4729 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4730 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4731 Fix, by Joel Brobecker imported from mainline.
4733 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4734 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4735 Fix, by Fred Fish, imported from mainline.
4737 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4738 Surprisingly enough, it works now.
4739 By Michal Ludvig, imported from mainline.
4741 i386 hardware watchpoint support:
4742 avoid misses on second run for some targets.
4743 By Pierre Muller, imported from mainline.
4745 *** Changes in GDB 5.2:
4747 * New command "set trust-readonly-sections on[off]".
4749 This command is a hint that tells gdb that read-only sections
4750 really are read-only (ie. that their contents will not change).
4751 In this mode, gdb will go to the object file rather than the
4752 target to read memory from read-only sections (such as ".text").
4753 This can be a significant performance improvement on some
4754 (notably embedded) targets.
4756 * New command "generate-core-file" (or "gcore").
4758 This new gdb command allows the user to drop a core file of the child
4759 process state at any time. So far it's been implemented only for
4760 GNU/Linux and Solaris, but should be relatively easily ported to other
4761 hosts. Argument is core file name (defaults to core.<pid>).
4763 * New command line option
4765 GDB now accepts --pid or -p followed by a process id.
4767 * Change in command line behavior -- corefiles vs. process ids.
4769 There is a subtle behavior in the way in which GDB handles
4770 command line arguments. The first non-flag argument is always
4771 a program to debug, but the second non-flag argument may either
4772 be a corefile or a process id. Previously, GDB would attempt to
4773 open the second argument as a corefile, and if that failed, would
4774 issue a superfluous error message and then attempt to attach it as
4775 a process. Now, if the second argument begins with a non-digit,
4776 it will be treated as a corefile. If it begins with a digit,
4777 GDB will attempt to attach it as a process, and if no such process
4778 is found, will then attempt to open it as a corefile.
4780 * Changes in ARM configurations.
4782 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4783 configuration is fully multi-arch.
4785 * New native configurations
4787 ARM NetBSD arm*-*-netbsd*
4788 x86 OpenBSD i[3456]86-*-openbsd*
4789 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4790 Sparc64 running FreeBSD sparc64-*-freebsd*
4794 Sanyo XStormy16 xstormy16-elf
4796 * OBSOLETE configurations and files
4798 Configurations that have been declared obsolete in this release have
4799 been commented out. Unless there is activity to revive these
4800 configurations, the next release of GDB will have their sources
4801 permanently REMOVED.
4803 AMD 29k family via UDI a29k-amd-udi, udi29k
4804 A29K VxWorks a29k-*-vxworks
4805 AMD 29000 embedded, using EBMON a29k-none-none
4806 AMD 29000 embedded with COFF a29k-none-coff
4807 AMD 29000 embedded with a.out a29k-none-aout
4809 testsuite/gdb.hp/gdb.threads-hp/ directory
4811 * REMOVED configurations and files
4813 TI TMS320C80 tic80-*-*
4815 PowerPC Solaris powerpcle-*-solaris*
4816 PowerPC Windows NT powerpcle-*-cygwin32
4817 PowerPC Netware powerpc-*-netware*
4818 Harris/CXUX m88k m88*-harris-cxux*
4819 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4820 ns32k-utek-sysv* ns32k-utek-*
4821 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4822 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4823 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4824 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4825 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4827 * Changes to command line processing
4829 The new `--args' feature can be used to specify command-line arguments
4830 for the inferior from gdb's command line.
4832 * Changes to key bindings
4834 There is a new `operate-and-get-next' function bound to `C-o'.
4836 *** Changes in GDB 5.1.1
4838 Fix compile problem on DJGPP.
4840 Fix a problem with floating-point registers on the i386 being
4843 Fix to stop GDB crashing on .debug_str debug info.
4845 Numerous documentation fixes.
4847 Numerous testsuite fixes.
4849 *** Changes in GDB 5.1:
4851 * New native configurations
4853 Alpha FreeBSD alpha*-*-freebsd*
4854 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4855 MIPS GNU/Linux mips*-*-linux*
4856 MIPS SGI Irix 6.x mips*-sgi-irix6*
4857 ia64 AIX ia64-*-aix*
4858 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4862 Motorola 68HC11 and 68HC12 m68hc11-elf
4864 UltraSparc running GNU/Linux sparc64-*-linux*
4866 * OBSOLETE configurations and files
4868 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4869 Harris/CXUX m88k m88*-harris-cxux*
4870 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4871 ns32k-utek-sysv* ns32k-utek-*
4872 TI TMS320C80 tic80-*-*
4874 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4875 PowerPC Solaris powerpcle-*-solaris*
4876 PowerPC Windows NT powerpcle-*-cygwin32
4877 PowerPC Netware powerpc-*-netware*
4878 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4879 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4880 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4881 Apple Macintosh (MPW) host N/A
4883 stuff.c (Program to stuff files into a specially prepared space in kdb)
4884 kdb-start.c (Main loop for the standalone kernel debugger)
4886 Configurations that have been declared obsolete in this release have
4887 been commented out. Unless there is activity to revive these
4888 configurations, the next release of GDB will have their sources
4889 permanently REMOVED.
4891 * REMOVED configurations and files
4893 Altos 3068 m68*-altos-*
4894 Convex c1-*-*, c2-*-*
4896 ARM RISCix arm-*-* (as host)
4900 * GDB has been converted to ISO C.
4902 GDB's source code has been converted to ISO C. In particular, the
4903 sources are fully protoized, and rely on standard headers being
4908 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4910 * The MI enabled by default.
4912 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4913 revised and enabled by default. Packages which use GDB as a debugging
4914 engine behind a UI or another front end are encouraged to switch to
4915 using the GDB/MI interface, instead of the old annotations interface
4916 which is now deprecated.
4918 * Support for debugging Pascal programs.
4920 GDB now includes support for debugging Pascal programs. The following
4921 main features are supported:
4923 - Pascal-specific data types such as sets;
4925 - automatic recognition of Pascal sources based on file-name
4928 - Pascal-style display of data types, variables, and functions;
4930 - a Pascal expression parser.
4932 However, some important features are not yet supported.
4934 - Pascal string operations are not supported at all;
4936 - there are some problems with boolean types;
4938 - Pascal type hexadecimal constants are not supported
4939 because they conflict with the internal variables format;
4941 - support for Pascal objects and classes is not full yet;
4943 - unlike Pascal, GDB is case-sensitive for symbol names.
4945 * Changes in completion.
4947 Commands such as `shell', `run' and `set args', which pass arguments
4948 to inferior programs, now complete on file names, similar to what
4949 users expect at the shell prompt.
4951 Commands which accept locations, such as `disassemble', `print',
4952 `breakpoint', `until', etc. now complete on filenames as well as
4953 program symbols. Thus, if you type "break foob TAB", and the source
4954 files linked into the programs include `foobar.c', that file name will
4955 be one of the candidates for completion. However, file names are not
4956 considered for completion after you typed a colon that delimits a file
4957 name from a name of a function in that file, as in "break foo.c:bar".
4959 `set demangle-style' completes on available demangling styles.
4961 * New platform-independent commands:
4963 It is now possible to define a post-hook for a command as well as a
4964 hook that runs before the command. For more details, see the
4965 documentation of `hookpost' in the GDB manual.
4967 * Changes in GNU/Linux native debugging.
4969 Support for debugging multi-threaded programs has been completely
4970 revised for all platforms except m68k and sparc. You can now debug as
4971 many threads as your system allows you to have.
4973 Attach/detach is supported for multi-threaded programs.
4975 Support for SSE registers was added for x86. This doesn't work for
4976 multi-threaded programs though.
4978 * Changes in MIPS configurations.
4980 Multi-arch support is enabled for all MIPS configurations.
4982 GDB can now be built as native debugger on SGI Irix 6.x systems for
4983 debugging n32 executables. (Debugging 64-bit executables is not yet
4986 * Unified support for hardware watchpoints in all x86 configurations.
4988 Most (if not all) native x86 configurations support hardware-assisted
4989 breakpoints and watchpoints in a unified manner. This support
4990 implements debug register sharing between watchpoints, which allows to
4991 put a virtually infinite number of watchpoints on the same address,
4992 and also supports watching regions up to 16 bytes with several debug
4995 The new maintenance command `maintenance show-debug-regs' toggles
4996 debugging print-outs in functions that insert, remove, and test
4997 watchpoints and hardware breakpoints.
4999 * Changes in the DJGPP native configuration.
5001 New command ``info dos sysinfo'' displays assorted information about
5002 the CPU, OS, memory, and DPMI server.
5004 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
5005 display information about segment descriptors stored in GDT, LDT, and
5008 New commands ``info dos pde'' and ``info dos pte'' display entries
5009 from Page Directory and Page Tables (for now works with CWSDPMI only).
5010 New command ``info dos address-pte'' displays the Page Table entry for
5011 a given linear address.
5013 GDB can now pass command lines longer than 126 characters to the
5014 program being debugged (requires an update to the libdbg.a library
5015 which is part of the DJGPP development kit).
5017 DWARF2 debug info is now supported.
5019 It is now possible to `step' and `next' through calls to `longjmp'.
5021 * Changes in documentation.
5023 All GDB documentation was converted to GFDL, the GNU Free
5024 Documentation License.
5026 Tracepoints-related commands are now fully documented in the GDB
5029 TUI, the Text-mode User Interface, is now documented in the manual.
5031 Tracepoints-related commands are now fully documented in the GDB
5034 The "GDB Internals" manual now has an index. It also includes
5035 documentation of `ui_out' functions, GDB coding standards, x86
5036 hardware watchpoints, and memory region attributes.
5038 * GDB's version number moved to ``version.in''
5040 The Makefile variable VERSION has been replaced by the file
5041 ``version.in''. People creating GDB distributions should update the
5042 contents of this file.
5046 GUD support is now a standard part of the EMACS distribution.
5048 *** Changes in GDB 5.0:
5050 * Improved support for debugging FP programs on x86 targets
5052 Unified and much-improved support for debugging floating-point
5053 programs on all x86 targets. In particular, ``info float'' now
5054 displays the FP registers in the same format on all x86 targets, with
5055 greater level of detail.
5057 * Improvements and bugfixes in hardware-assisted watchpoints
5059 It is now possible to watch array elements, struct members, and
5060 bitfields with hardware-assisted watchpoints. Data-read watchpoints
5061 on x86 targets no longer erroneously trigger when the address is
5064 * Improvements in the native DJGPP version of GDB
5066 The distribution now includes all the scripts and auxiliary files
5067 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5068 machines ``out of the box''.
5070 The DJGPP version can now debug programs that use signals. It is
5071 possible to catch signals that happened in the debuggee, deliver
5072 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5073 would kill the program being debugged.) Programs that hook hardware
5074 interrupts (keyboard, timer, etc.) can also be debugged.
5076 It is now possible to debug DJGPP programs that redirect their
5077 standard handles or switch them to raw (as opposed to cooked) mode, or
5078 even close them. The command ``run < foo > bar'' works as expected,
5079 and ``info terminal'' reports useful information about the debuggee's
5080 terminal, including raw/cooked mode, redirection, etc.
5082 The DJGPP version now uses termios functions for console I/O, which
5083 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5086 DOS-style file names with drive letters are now fully supported by
5089 It is now possible to debug DJGPP programs that switch their working
5090 directory. It is also possible to rerun the debuggee any number of
5091 times without restarting GDB; thus, you can use the same setup,
5092 breakpoints, etc. for many debugging sessions.
5094 * New native configurations
5096 ARM GNU/Linux arm*-*-linux*
5097 PowerPC GNU/Linux powerpc-*-linux*
5101 Motorola MCore mcore-*-*
5102 x86 VxWorks i[3456]86-*-vxworks*
5103 PowerPC VxWorks powerpc-*-vxworks*
5104 TI TMS320C80 tic80-*-*
5106 * OBSOLETE configurations
5108 Altos 3068 m68*-altos-*
5109 Convex c1-*-*, c2-*-*
5111 ARM RISCix arm-*-* (as host)
5114 Configurations that have been declared obsolete will be commented out,
5115 but the code will be left in place. If there is no activity to revive
5116 these configurations before the next release of GDB, the sources will
5117 be permanently REMOVED.
5119 * Gould support removed
5121 Support for the Gould PowerNode and NP1 has been removed.
5123 * New features for SVR4
5125 On SVR4 native platforms (such as Solaris), if you attach to a process
5126 without first loading a symbol file, GDB will now attempt to locate and
5127 load symbols from the running process's executable file.
5129 * Many C++ enhancements
5131 C++ support has been greatly improved. Overload resolution now works properly
5132 in almost all cases. RTTI support is on the way.
5134 * Remote targets can connect to a sub-program
5136 A popen(3) style serial-device has been added. This device starts a
5137 sub-process (such as a stand-alone simulator) and then communicates
5138 with that. The sub-program to run is specified using the syntax
5139 ``|<program> <args>'' vis:
5141 (gdb) set remotedebug 1
5142 (gdb) target extended-remote |mn10300-elf-sim program-args
5144 * MIPS 64 remote protocol
5146 A long standing bug in the mips64 remote protocol where by GDB
5147 expected certain 32 bit registers (ex SR) to be transfered as 32
5148 instead of 64 bits has been fixed.
5150 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5151 added to provide backward compatibility with older versions of GDB.
5153 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5155 The command ``set remotebinarydownload'' command has been replaced by
5156 ``set remote X-packet''. Other commands in ``set remote'' family
5157 include ``set remote P-packet''.
5159 * Breakpoint commands accept ranges.
5161 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5162 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5163 ``tracepoint passcount'' also accepts a range of tracepoints.
5165 * ``apropos'' command added.
5167 The ``apropos'' command searches through command names and
5168 documentation strings, printing out matches, making it much easier to
5169 try to find a command that does what you are looking for.
5173 A new machine oriented interface (MI) has been added to GDB. This
5174 interface is designed for debug environments running GDB as a separate
5175 process. This is part of the long term libGDB project. See the
5176 "GDB/MI" chapter of the GDB manual for further information. It can be
5177 enabled by configuring with:
5179 .../configure --enable-gdbmi
5181 *** Changes in GDB-4.18:
5183 * New native configurations
5185 HP-UX 10.20 hppa*-*-hpux10.20
5186 HP-UX 11.x hppa*-*-hpux11.0*
5187 M68K GNU/Linux m68*-*-linux*
5191 Fujitsu FR30 fr30-*-elf*
5192 Intel StrongARM strongarm-*-*
5193 Mitsubishi D30V d30v-*-*
5195 * OBSOLETE configurations
5197 Gould PowerNode, NP1 np1-*-*, pn-*-*
5199 Configurations that have been declared obsolete will be commented out,
5200 but the code will be left in place. If there is no activity to revive
5201 these configurations before the next release of GDB, the sources will
5202 be permanently REMOVED.
5206 As a compatibility experiment, GDB's source files buildsym.h and
5207 buildsym.c have been converted to pure standard C, no longer
5208 containing any K&R compatibility code. We believe that all systems in
5209 use today either come with a standard C compiler, or have a GCC port
5210 available. If this is not true, please report the affected
5211 configuration to bug-gdb@gnu.org immediately. See the README file for
5212 information about getting a standard C compiler if you don't have one
5217 GDB now uses readline 2.2.
5219 * set extension-language
5221 You can now control the mapping between filename extensions and source
5222 languages by using the `set extension-language' command. For instance,
5223 you can ask GDB to treat .c files as C++ by saying
5224 set extension-language .c c++
5225 The command `info extensions' lists all of the recognized extensions
5226 and their associated languages.
5228 * Setting processor type for PowerPC and RS/6000
5230 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5231 you can use the `set processor' command to specify what variant of the
5232 PowerPC family you are debugging. The command
5236 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5237 following PowerPC and RS6000 variants:
5239 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5240 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5242 403GC IBM PowerPC 403GC
5243 505 Motorola PowerPC 505
5244 860 Motorola PowerPC 860 or 850
5245 601 Motorola PowerPC 601
5246 602 Motorola PowerPC 602
5247 603 Motorola/IBM PowerPC 603 or 603e
5248 604 Motorola PowerPC 604 or 604e
5249 750 Motorola/IBM PowerPC 750 or 750
5251 At the moment, this command just tells GDB what to name the
5252 special-purpose processor registers. Since almost all the affected
5253 registers are inaccessible to user-level programs, this command is
5254 only useful for remote debugging in its present form.
5258 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5259 more extensive support for HP-UX. Added features include shared
5260 library support, kernel threads and hardware watchpoints for 11.00,
5261 support for HP's ANSI C and C++ compilers, and a compatibility mode
5262 for xdb and dbx commands.
5266 HP's donation includes the new concept of catchpoints, which is a
5267 generalization of the old catch command. On HP-UX, it is now possible
5268 to catch exec, fork, and vfork, as well as library loading.
5270 This means that the existing catch command has changed; its first
5271 argument now specifies the type of catch to be set up. See the
5272 output of "help catch" for a list of catchpoint types.
5274 * Debugging across forks
5276 On HP-UX, you can choose which process to debug when a fork() happens
5281 HP has donated a curses-based terminal user interface (TUI). To get
5282 it, build with --enable-tui. Although this can be enabled for any
5283 configuration, at present it only works for native HP debugging.
5285 * GDB remote protocol additions
5287 A new protocol packet 'X' that writes binary data is now available.
5288 Default behavior is to try 'X', then drop back to 'M' if the stub
5289 fails to respond. The settable variable `remotebinarydownload'
5290 allows explicit control over the use of 'X'.
5292 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5293 full 64-bit address. The command
5295 set remoteaddresssize 32
5297 can be used to revert to the old behaviour. For existing remote stubs
5298 the change should not be noticed, as the additional address information
5301 In order to assist in debugging stubs, you may use the maintenance
5302 command `packet' to send any text string to the stub. For instance,
5304 maint packet heythere
5306 sends the packet "$heythere#<checksum>". Note that it is very easy to
5307 disrupt a debugging session by sending the wrong packet at the wrong
5310 The compare-sections command allows you to compare section data on the
5311 target to what is in the executable file without uploading or
5312 downloading, by comparing CRC checksums.
5314 * Tracing can collect general expressions
5316 You may now collect general expressions at tracepoints. This requires
5317 further additions to the target-side stub; see tracepoint.c and
5318 doc/agentexpr.texi for further details.
5320 * mask-address variable for Mips
5322 For Mips targets, you may control the zeroing of the upper 32 bits of
5323 a 64-bit address by entering `set mask-address on'. This is mainly
5324 of interest to users of embedded R4xxx and R5xxx processors.
5326 * Higher serial baud rates
5328 GDB's serial code now allows you to specify baud rates 57600, 115200,
5329 230400, and 460800 baud. (Note that your host system may not be able
5330 to achieve all of these rates.)
5334 The i960 configuration now includes an initial implementation of a
5335 builtin simulator, contributed by Jim Wilson.
5338 *** Changes in GDB-4.17:
5340 * New native configurations
5342 Alpha GNU/Linux alpha*-*-linux*
5343 Unixware 2.x i[3456]86-unixware2*
5344 Irix 6.x mips*-sgi-irix6*
5345 PowerPC GNU/Linux powerpc-*-linux*
5346 PowerPC Solaris powerpcle-*-solaris*
5347 Sparc GNU/Linux sparc-*-linux*
5348 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5352 Argonaut Risc Chip (ARC) arc-*-*
5353 Hitachi H8/300S h8300*-*-*
5354 Matsushita MN10200 w/simulator mn10200-*-*
5355 Matsushita MN10300 w/simulator mn10300-*-*
5356 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5357 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5358 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5359 Mitsubishi D10V w/simulator d10v-*-*
5360 Mitsubishi M32R/D w/simulator m32r-*-elf*
5361 Tsqware Sparclet sparclet-*-*
5362 NEC V850 w/simulator v850-*-*
5364 * New debugging protocols
5366 ARM with RDI protocol arm*-*-*
5367 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5368 DDB and LSI variants of PMON protocol mips*-*-*
5369 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5370 PowerPC with SDS protocol powerpc{,le}-*-eabi
5371 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5375 All configurations can now understand and use the DWARF 2 debugging
5376 format. The choice is automatic, if the symbol file contains DWARF 2
5381 GDB now includes basic Java language support. This support is
5382 only useful with Java compilers that produce native machine code.
5384 * solib-absolute-prefix and solib-search-path
5386 For SunOS and SVR4 shared libraries, you may now set the prefix for
5387 loading absolute shared library symbol files, and the search path for
5388 locating non-absolute shared library symbol files.
5390 * Live range splitting
5392 GDB can now effectively debug code for which GCC has performed live
5393 range splitting as part of its optimization. See gdb/doc/LRS for
5394 more details on the expected format of the stabs information.
5398 GDB's support for the GNU Hurd, including thread debugging, has been
5399 updated to work with current versions of the Hurd.
5403 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5404 instruction set. ARM GDB automatically detects when Thumb
5405 instructions are in use, and adjusts disassembly and backtracing
5410 GDB's MIPS target configurations now handle the MIP16 16-bit
5415 GDB now includes support for overlays; if an executable has been
5416 linked such that multiple sections are based at the same address, GDB
5417 will decide which section to use for symbolic info. You can choose to
5418 control the decision manually, using overlay commands, or implement
5419 additional target-side support and use "overlay load-target" to bring
5420 in the overlay mapping. Do "help overlay" for more detail.
5424 The command "info symbol <address>" displays information about
5425 the symbol at the specified address.
5429 The standard remote protocol now includes an extension that allows
5430 asynchronous collection and display of trace data. This requires
5431 extensive support in the target-side debugging stub. Tracing mode
5432 includes a new interaction mode in GDB and new commands: see the
5433 file tracepoint.c for more details.
5437 Configurations for embedded MIPS now include a simulator contributed
5438 by Cygnus Solutions. The simulator supports the instruction sets
5439 of most MIPS variants.
5443 Sparc configurations may now include the ERC32 simulator contributed
5444 by the European Space Agency. The simulator is not built into
5445 Sparc targets by default; configure with --enable-sim to include it.
5449 For target configurations that may include multiple variants of a
5450 basic architecture (such as MIPS and SH), you may now set the
5451 architecture explicitly. "set arch" sets, "info arch" lists
5452 the possible architectures.
5454 *** Changes in GDB-4.16:
5456 * New native configurations
5458 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5459 M68K NetBSD m68k-*-netbsd*
5460 PowerPC AIX 4.x powerpc-*-aix*
5461 PowerPC MacOS powerpc-*-macos*
5462 PowerPC Windows NT powerpcle-*-cygwin32
5463 RS/6000 AIX 4.x rs6000-*-aix4*
5467 ARM with RDP protocol arm-*-*
5468 I960 with MON960 i960-*-coff
5469 MIPS VxWorks mips*-*-vxworks*
5470 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5471 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5473 Matra Sparclet sparclet-*-*
5477 The powerpc-eabi configuration now includes the PSIM simulator,
5478 contributed by Andrew Cagney, with assistance from Mike Meissner.
5479 PSIM is a very elaborate model of the PowerPC, including not only
5480 basic instruction set execution, but also details of execution unit
5481 performance and I/O hardware. See sim/ppc/README for more details.
5485 GDB now works with Solaris 2.5.
5487 * Windows 95/NT native
5489 GDB will now work as a native debugger on Windows 95 and Windows NT.
5490 To build it from source, you must use the "gnu-win32" environment,
5491 which uses a DLL to emulate enough of Unix to run the GNU tools.
5492 Further information, binaries, and sources are available at
5493 ftp.cygnus.com, under pub/gnu-win32.
5495 * dont-repeat command
5497 If a user-defined command includes the command `dont-repeat', then the
5498 command will not be repeated if the user just types return. This is
5499 useful if the command is time-consuming to run, so that accidental
5500 extra keystrokes don't run the same command many times.
5502 * Send break instead of ^C
5504 The standard remote protocol now includes an option to send a break
5505 rather than a ^C to the target in order to interrupt it. By default,
5506 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5508 * Remote protocol timeout
5510 The standard remote protocol includes a new variable `remotetimeout'
5511 that allows you to set the number of seconds before GDB gives up trying
5512 to read from the target. The default value is 2.
5514 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5516 By default GDB will automatically keep track of objects as they are
5517 loaded and unloaded by the dynamic linker. By using the command `set
5518 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5519 when shared library events occur, thus allowing you to set breakpoints
5520 in shared libraries which are explicitly loaded by the inferior.
5522 Note this feature does not work on hpux8. On hpux9 you must link
5523 /usr/lib/end.o into your program. This feature should work
5524 automatically on hpux10.
5526 * Irix 5.x hardware watchpoint support
5528 Irix 5 configurations now support the use of hardware watchpoints.
5530 * Mips protocol "SYN garbage limit"
5532 When debugging a Mips target using the `target mips' protocol, you
5533 may set the number of characters that GDB will ignore by setting
5534 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5535 every character. The default value is 1050.
5537 * Recording and replaying remote debug sessions
5539 If you set `remotelogfile' to the name of a file, gdb will write to it
5540 a recording of a remote debug session. This recording may then be
5541 replayed back to gdb using "gdbreplay". See gdbserver/README for
5542 details. This is useful when you have a problem with GDB while doing
5543 remote debugging; you can make a recording of the session and send it
5544 to someone else, who can then recreate the problem.
5546 * Speedups for remote debugging
5548 GDB includes speedups for downloading and stepping MIPS systems using
5549 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5550 and more efficient S-record downloading.
5552 * Memory use reductions and statistics collection
5554 GDB now uses less memory and reports statistics about memory usage.
5555 Try the `maint print statistics' command, for example.
5557 *** Changes in GDB-4.15:
5559 * Psymtabs for XCOFF
5561 The symbol reader for AIX GDB now uses partial symbol tables. This
5562 can greatly improve startup time, especially for large executables.
5564 * Remote targets use caching
5566 Remote targets now use a data cache to speed up communication with the
5567 remote side. The data cache could lead to incorrect results because
5568 it doesn't know about volatile variables, thus making it impossible to
5569 debug targets which use memory mapped I/O devices. `set remotecache
5570 off' turns the the data cache off.
5572 * Remote targets may have threads
5574 The standard remote protocol now includes support for multiple threads
5575 in the target system, using new protocol commands 'H' and 'T'. See
5576 gdb/remote.c for details.
5580 If GDB is configured with `--enable-netrom', then it will include
5581 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5582 acts as though it is a bank of ROM on the target board, but you can
5583 write into it over the network. GDB's support consists only of
5584 support for fast loading into the emulated ROM; to debug, you must use
5585 another protocol, such as standard remote protocol. The usual
5586 sequence is something like
5588 target nrom <netrom-hostname>
5590 target remote <netrom-hostname>:1235
5594 GDB now includes support for the Apple Macintosh, as a host only. It
5595 may be run as either an MPW tool or as a standalone application, and
5596 it can debug through the serial port. All the usual GDB commands are
5597 available, but to the target command, you must supply "serial" as the
5598 device type instead of "/dev/ttyXX". See mpw-README in the main
5599 directory for more information on how to build. The MPW configuration
5600 scripts */mpw-config.in support only a few targets, and only the
5601 mips-idt-ecoff target has been tested.
5605 GDB configuration now uses autoconf. This is not user-visible,
5606 but does simplify configuration and building.
5610 GDB now supports hpux10.
5612 *** Changes in GDB-4.14:
5614 * New native configurations
5616 x86 FreeBSD i[345]86-*-freebsd
5617 x86 NetBSD i[345]86-*-netbsd
5618 NS32k NetBSD ns32k-*-netbsd
5619 Sparc NetBSD sparc-*-netbsd
5623 A29K VxWorks a29k-*-vxworks
5624 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5625 CPU32 EST-300 emulator m68*-*-est*
5626 PowerPC ELF powerpc-*-elf
5629 * Alpha OSF/1 support for procfs
5631 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5632 possible to attach to running processes. As the mounting of the /proc
5633 filesystem is optional on the Alpha, GDB automatically determines
5634 the availability of /proc during startup. This can lead to problems
5635 if /proc is unmounted after GDB has been started.
5637 * Arguments to user-defined commands
5639 User commands may accept up to 10 arguments separated by whitespace.
5640 Arguments are accessed within the user command via $arg0..$arg9. A
5643 print $arg0 + $arg1 + $arg2
5645 To execute the command use:
5648 Defines the command "adder" which prints the sum of its three arguments.
5649 Note the arguments are text substitutions, so they may reference variables,
5650 use complex expressions, or even perform inferior function calls.
5652 * New `if' and `while' commands
5654 This makes it possible to write more sophisticated user-defined
5655 commands. Both commands take a single argument, which is the
5656 expression to evaluate, and must be followed by the commands to
5657 execute, one per line, if the expression is nonzero, the list being
5658 terminated by the word `end'. The `if' command list may include an
5659 `else' word, which causes the following commands to be executed only
5660 if the expression is zero.
5662 * Fortran source language mode
5664 GDB now includes partial support for Fortran 77. It will recognize
5665 Fortran programs and can evaluate a subset of Fortran expressions, but
5666 variables and functions may not be handled correctly. GDB will work
5667 with G77, but does not yet know much about symbols emitted by other
5670 * Better HPUX support
5672 Most debugging facilities now work on dynamic executables for HPPAs
5673 running hpux9 or later. You can attach to running dynamically linked
5674 processes, but by default the dynamic libraries will be read-only, so
5675 for instance you won't be able to put breakpoints in them. To change
5676 that behavior do the following before running the program:
5682 This will cause the libraries to be mapped private and read-write.
5683 To revert to the normal behavior, do this:
5689 You cannot set breakpoints or examine data in the library until after
5690 the library is loaded if the function/data symbols do not have
5693 GDB can now also read debug symbols produced by the HP C compiler on
5694 HPPAs (sorry, no C++, Fortran or 68k support).
5696 * Target byte order now dynamically selectable
5698 You can choose which byte order to use with a target system, via the
5699 commands "set endian big" and "set endian little", and you can see the
5700 current setting by using "show endian". You can also give the command
5701 "set endian auto", in which case GDB will use the byte order
5702 associated with the executable. Currently, only embedded MIPS
5703 configurations support dynamic selection of target byte order.
5705 * New DOS host serial code
5707 This version uses DPMI interrupts to handle buffered I/O, so you
5708 no longer need to run asynctsr when debugging boards connected to
5711 *** Changes in GDB-4.13:
5713 * New "complete" command
5715 This lists all the possible completions for the rest of the line, if it
5716 were to be given as a command itself. This is intended for use by emacs.
5718 * Trailing space optional in prompt
5720 "set prompt" no longer adds a space for you after the prompt you set. This
5721 allows you to set a prompt which ends in a space or one that does not.
5723 * Breakpoint hit counts
5725 "info break" now displays a count of the number of times the breakpoint
5726 has been hit. This is especially useful in conjunction with "ignore"; you
5727 can ignore a large number of breakpoint hits, look at the breakpoint info
5728 to see how many times the breakpoint was hit, then run again, ignoring one
5729 less than that number, and this will get you quickly to the last hit of
5732 * Ability to stop printing at NULL character
5734 "set print null-stop" will cause GDB to stop printing the characters of
5735 an array when the first NULL is encountered. This is useful when large
5736 arrays actually contain only short strings.
5738 * Shared library breakpoints
5740 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5741 breakpoints in shared libraries before the executable is run.
5743 * Hardware watchpoints
5745 There is a new hardware breakpoint for the watch command for sparclite
5746 targets. See gdb/sparclite/hw_breakpoint.note.
5748 Hardware watchpoints are also now supported under GNU/Linux.
5752 Annotations have been added. These are for use with graphical interfaces,
5753 and are still experimental. Currently only gdba.el uses these.
5755 * Improved Irix 5 support
5757 GDB now works properly with Irix 5.2.
5759 * Improved HPPA support
5761 GDB now works properly with the latest GCC and GAS.
5763 * New native configurations
5765 Sequent PTX4 i[34]86-sequent-ptx4
5766 HPPA running OSF/1 hppa*-*-osf*
5767 Atari TT running SVR4 m68*-*-sysv4*
5768 RS/6000 LynxOS rs6000-*-lynxos*
5772 OS/9000 i[34]86-*-os9k
5773 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5776 * Hitachi SH7000 and E7000-PC ICE support
5778 There is now support for communicating with the Hitachi E7000-PC ICE.
5779 This is available automatically when GDB is configured for the SH.
5783 As usual, a variety of small fixes and improvements, both generic
5784 and configuration-specific. See the ChangeLog for more detail.
5786 *** Changes in GDB-4.12:
5788 * Irix 5 is now supported
5792 GDB-4.12 on the HPPA has a number of changes which make it unable
5793 to debug the output from the currently released versions of GCC and
5794 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5795 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5796 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5799 *** Changes in GDB-4.11:
5801 * User visible changes:
5805 The "set remotedebug" option is now consistent between the mips remote
5806 target, remote targets using the gdb-specific protocol, UDI (AMD's
5807 debug protocol for the 29k) and the 88k bug monitor. It is now an
5808 integer specifying a debug level (normally 0 or 1, but 2 means more
5809 debugging info for the mips target).
5811 * DEC Alpha native support
5813 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5814 debug info, but GDB works fairly well with the DEC compiler and should
5815 work with a future GCC release. See the README file for a few
5816 Alpha-specific notes.
5818 * Preliminary thread implementation
5820 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5822 * LynxOS native and target support for 386
5824 This release has been hosted on LynxOS 2.2, and also can be configured
5825 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5828 * Improvements in C++ mangling/demangling.
5830 This release has much better g++ debugging, specifically in name
5831 mangling/demangling, virtual function calls, print virtual table,
5832 call methods, ...etc.
5834 *** Changes in GDB-4.10:
5836 * User visible changes:
5838 Remote debugging using the GDB-specific (`target remote') protocol now
5839 supports the `load' command. This is only useful if you have some
5840 other way of getting the stub to the target system, and you can put it
5841 somewhere in memory where it won't get clobbered by the download.
5843 Filename completion now works.
5845 When run under emacs mode, the "info line" command now causes the
5846 arrow to point to the line specified. Also, "info line" prints
5847 addresses in symbolic form (as well as hex).
5849 All vxworks based targets now support a user settable option, called
5850 vxworks-timeout. This option represents the number of seconds gdb
5851 should wait for responses to rpc's. You might want to use this if
5852 your vxworks target is, perhaps, a slow software simulator or happens
5853 to be on the far side of a thin network line.
5857 This release contains support for using a DEC alpha as a GDB host for
5858 cross debugging. Native alpha debugging is not supported yet.
5861 *** Changes in GDB-4.9:
5865 This is the first GDB release which is accompanied by a matching testsuite.
5866 The testsuite requires installation of dejagnu, which should be available
5867 via ftp from most sites that carry GNU software.
5871 'Cfront' style demangling has had its name changed to 'ARM' style, to
5872 emphasize that it was written from the specifications in the C++ Annotated
5873 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5874 disclaimers, it still generated too much confusion with users attempting to
5875 use gdb with AT&T cfront.
5879 GDB now uses a standard remote interface to a simulator library.
5880 So far, the library contains simulators for the Zilog Z8001/2, the
5881 Hitachi H8/300, H8/500 and Super-H.
5883 * New targets supported
5885 H8/300 simulator h8300-hitachi-hms or h8300hms
5886 H8/500 simulator h8500-hitachi-hms or h8500hms
5887 SH simulator sh-hitachi-hms or sh
5888 Z8000 simulator z8k-zilog-none or z8ksim
5889 IDT MIPS board over serial line mips-idt-ecoff
5891 Cross-debugging to GO32 targets is supported. It requires a custom
5892 version of the i386-stub.c module which is integrated with the
5893 GO32 memory extender.
5895 * New remote protocols
5897 MIPS remote debugging protocol.
5899 * New source languages supported
5901 This version includes preliminary support for Chill, a Pascal like language
5902 used by telecommunications companies. Chill support is also being integrated
5903 into the GNU compiler, but we don't know when it will be publically available.
5906 *** Changes in GDB-4.8:
5908 * HP Precision Architecture supported
5910 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5911 version of this support was available as a set of patches from the
5912 University of Utah. GDB does not support debugging of programs
5913 compiled with the HP compiler, because HP will not document their file
5914 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5915 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5917 Many problems in the preliminary version have been fixed.
5919 * Faster and better demangling
5921 We have improved template demangling and fixed numerous bugs in the GNU style
5922 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5923 character types (wchar_t) are now supported. Demangling of each symbol is now
5924 only done once, and is cached when the symbol table for a file is read in.
5925 This results in a small increase in memory usage for C programs, a moderate
5926 increase in memory usage for C++ programs, and a fantastic speedup in
5929 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5930 from the specifications in the Annotated Reference Manual, which AT&T's
5931 compiler does not actually implement.
5933 * G++ multiple inheritance compiler problem
5935 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5936 inheritance lattices was reworked to properly discover ambiguities. We
5937 recently found an example which causes this new algorithm to fail in a
5938 very subtle way, producing bad debug information for those classes.
5939 The file 'gcc.patch' (in this directory) can be applied to gcc to
5940 circumvent the problem. A future GCC release will contain a complete
5943 The previous G++ debug info problem (mentioned below for the gdb-4.7
5944 release) is fixed in gcc version 2.3.2.
5946 * Improved configure script
5948 The `configure' script will now attempt to guess your system type if
5949 you don't supply a host system type. The old scheme of supplying a
5950 host system triplet is preferable over using this. All the magic is
5951 done in the new `config.guess' script. Examine it for details.
5953 We have also brought our configure script much more in line with the FSF's
5954 version. It now supports the --with-xxx options. In particular,
5955 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5956 The resulting GDB will not be able to read arbitrary object file formats --
5957 only the format ``expected'' to be used on the configured target system.
5958 We hope to make this the default in a future release.
5960 * Documentation improvements
5962 There's new internal documentation on how to modify GDB, and how to
5963 produce clean changes to the code. We implore people to read it
5964 before submitting changes.
5966 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5967 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5968 `info' files are also provided. To build `info' files from scratch,
5969 you will need the latest `makeinfo' release, which will be available in
5970 a future texinfo-X.Y release.
5972 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5973 We're not sure exactly which versions have this problem, but it has
5974 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5975 or better. If that isn't possible, there is a patch in
5976 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5977 around this problem.
5981 GDB now supports array constants that can be used in expressions typed in by
5982 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5983 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5986 The new directory `gdb/sparclite' contains a program that demonstrates
5987 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5989 * New native hosts supported
5991 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5992 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5994 * New targets supported
5996 AMD 29k family via UDI a29k-amd-udi or udi29k
5998 * New file formats supported
6000 BFD now supports reading HP/PA-RISC executables (SOM file format?),
6001 HPUX core files, and SCO 3.2v2 core files.
6005 Attaching to processes now works again; thanks for the many bug reports.
6007 We have also stomped on a bunch of core dumps caused by
6008 printf_filtered("%s") problems.
6010 We eliminated a copyright problem on the rpc and ptrace header files
6011 for VxWorks, which was discovered at the last minute during the 4.7
6012 release. You should now be able to build a VxWorks GDB.
6014 You can now interrupt gdb while an attached process is running. This
6015 will cause the attached process to stop, and give control back to GDB.
6017 We fixed problems caused by using too many file descriptors
6018 for reading symbols from object files and libraries. This was
6019 especially a problem for programs that used many (~100) shared
6022 The `step' command now only enters a subroutine if there is line number
6023 information for the subroutine. Otherwise it acts like the `next'
6024 command. Previously, `step' would enter subroutines if there was
6025 any debugging information about the routine. This avoids problems
6026 when using `cc -g1' on MIPS machines.
6028 * Internal improvements
6030 GDB's internal interfaces have been improved to make it easier to support
6031 debugging of multiple languages in the future.
6033 GDB now uses a common structure for symbol information internally.
6034 Minimal symbols (derived from linkage symbols in object files), partial
6035 symbols (from a quick scan of debug information), and full symbols
6036 contain a common subset of information, making it easier to write
6037 shared code that handles any of them.
6039 * New command line options
6041 We now accept --silent as an alias for --quiet.
6045 The memory-mapped-malloc library is now licensed under the GNU Library
6046 General Public License.
6048 *** Changes in GDB-4.7:
6050 * Host/native/target split
6052 GDB has had some major internal surgery to untangle the support for
6053 hosts and remote targets. Now, when you configure GDB for a remote
6054 target, it will no longer load in all of the support for debugging
6055 local programs on the host. When fully completed and tested, this will
6056 ensure that arbitrary host/target combinations are possible.
6058 The primary conceptual shift is to separate the non-portable code in
6059 GDB into three categories. Host specific code is required any time GDB
6060 is compiled on that host, regardless of the target. Target specific
6061 code relates to the peculiarities of the target, but can be compiled on
6062 any host. Native specific code is everything else: it can only be
6063 built when the host and target are the same system. Child process
6064 handling and core file support are two common `native' examples.
6066 GDB's use of /proc for controlling Unix child processes is now cleaner.
6067 It has been split out into a single module under the `target_ops' vector,
6068 plus two native-dependent functions for each system that uses /proc.
6070 * New hosts supported
6072 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6073 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6074 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6076 * New targets supported
6078 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6079 68030 and CPU32 m68030-*-*, m68332-*-*
6081 * New native hosts supported
6083 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6084 (386bsd is not well tested yet)
6085 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6087 * New file formats supported
6089 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6090 supports reading of `a.out.adobe' object files, which are an a.out
6091 format extended with minimal information about multiple sections.
6095 `show copying' is the same as the old `info copying'.
6096 `show warranty' is the same as `info warrantee'.
6097 These were renamed for consistency. The old commands continue to work.
6099 `info handle' is a new alias for `info signals'.
6101 You can now define pre-command hooks, which attach arbitrary command
6102 scripts to any command. The commands in the hook will be executed
6103 prior to the user's command. You can also create a hook which will be
6104 executed whenever the program stops. See gdb.texinfo.
6108 We now deal with Cfront style name mangling, and can even extract type
6109 info from mangled symbols. GDB can automatically figure out which
6110 symbol mangling style your C++ compiler uses.
6112 Calling of methods and virtual functions has been improved as well.
6116 The crash that occured when debugging Sun Ansi-C compiled binaries is
6117 fixed. This was due to mishandling of the extra N_SO stabs output
6120 We also finally got Ultrix 4.2 running in house, and fixed core file
6121 support, with help from a dozen people on the net.
6123 John M. Farrell discovered that the reason that single-stepping was so
6124 slow on all of the Mips based platforms (primarily SGI and DEC) was
6125 that we were trying to demangle and lookup a symbol used for internal
6126 purposes on every instruction that was being stepped through. Changing
6127 the name of that symbol so that it couldn't be mistaken for a C++
6128 mangled symbol sped things up a great deal.
6130 Rich Pixley sped up symbol lookups in general by getting much smarter
6131 about when C++ symbol mangling is necessary. This should make symbol
6132 completion (TAB on the command line) much faster. It's not as fast as
6133 we'd like, but it's significantly faster than gdb-4.6.
6137 A new user controllable variable 'call_scratch_address' can
6138 specify the location of a scratch area to be used when GDB
6139 calls a function in the target. This is necessary because the
6140 usual method of putting the scratch area on the stack does not work
6141 in systems that have separate instruction and data spaces.
6143 We integrated changes to support the 29k UDI (Universal Debugger
6144 Interface), but discovered at the last minute that we didn't have all
6145 of the appropriate copyright paperwork. We are working with AMD to
6146 resolve this, and hope to have it available soon.
6150 We have sped up the remote serial line protocol, especially for targets
6151 with lots of registers. It now supports a new `expedited status' ('T')
6152 message which can be used in place of the existing 'S' status message.
6153 This allows the remote stub to send only the registers that GDB
6154 needs to make a quick decision about single-stepping or conditional
6155 breakpoints, eliminating the need to fetch the entire register set for
6156 each instruction being stepped through.
6158 The GDB remote serial protocol now implements a write-through cache for
6159 registers, only re-reading the registers if the target has run.
6161 There is also a new remote serial stub for SPARC processors. You can
6162 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6163 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6164 processor with a serial port.
6168 Configure.in files have become much easier to read and modify. A new
6169 `table driven' format makes it more obvious what configurations are
6170 supported, and what files each one uses.
6174 There is a new opcodes library which will eventually contain all of the
6175 disassembly routines and opcode tables. At present, it only contains
6176 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6177 disassembler (binutils/objdump) to share these routines.
6179 The libiberty library is now copylefted under the GNU Library General
6180 Public License. This allows more liberal use, and was done so libg++
6181 can use it. This makes no difference to GDB, since the Library License
6182 grants all the rights from the General Public License.
6186 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6187 reference to the stabs symbol info used by the debugger. It is (as far
6188 as we know) the only published document on this fascinating topic. We
6189 encourage you to read it, compare it to the stabs information on your
6190 system, and send improvements on the document in general (to
6191 bug-gdb@prep.ai.mit.edu).
6193 And, of course, many bugs have been fixed.
6196 *** Changes in GDB-4.6:
6198 * Better support for C++ function names
6200 GDB now accepts as input the "demangled form" of C++ overloaded function
6201 names and member function names, and can do command completion on such names
6202 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6203 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6204 Make use of command completion, it is your friend.
6206 GDB also now accepts a variety of C++ mangled symbol formats. They are
6207 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6208 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6209 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6210 for the list of formats.
6212 * G++ symbol mangling problem
6214 Recent versions of gcc have a bug in how they emit debugging information for
6215 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6216 directory) can be applied to gcc to fix the problem. Alternatively, if you
6217 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6218 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6219 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6222 * New 'maintenance' command
6224 All of the commands related to hacking GDB internals have been moved out of
6225 the main command set, and now live behind the 'maintenance' command. This
6226 can also be abbreviated as 'mt'. The following changes were made:
6228 dump-me -> maintenance dump-me
6229 info all-breakpoints -> maintenance info breakpoints
6230 printmsyms -> maintenance print msyms
6231 printobjfiles -> maintenance print objfiles
6232 printpsyms -> maintenance print psymbols
6233 printsyms -> maintenance print symbols
6235 The following commands are new:
6237 maintenance demangle Call internal GDB demangler routine to
6238 demangle a C++ link name and prints the result.
6239 maintenance print type Print a type chain for a given symbol
6241 * Change to .gdbinit file processing
6243 We now read the $HOME/.gdbinit file before processing the argv arguments
6244 (e.g. reading symbol files or core files). This allows global parameters to
6245 be set, which will apply during the symbol reading. The ./.gdbinit is still
6246 read after argv processing.
6248 * New hosts supported
6250 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6252 GNU/Linux support i386-unknown-linux or linux
6254 We are also including code to support the HP/PA running BSD and HPUX. This
6255 is almost guaranteed not to work, as we didn't have time to test or build it
6256 for this release. We are including it so that the more adventurous (or
6257 masochistic) of you can play with it. We also had major problems with the
6258 fact that the compiler that we got from HP doesn't support the -g option.
6261 * New targets supported
6263 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6265 * More smarts about finding #include files
6267 GDB now remembers the compilation directory for all include files, and for
6268 all files from which C is generated (like yacc and lex sources). This
6269 greatly improves GDB's ability to find yacc/lex sources, and include files,
6270 especially if you are debugging your program from a directory different from
6271 the one that contains your sources.
6273 We also fixed a bug which caused difficulty with listing and setting
6274 breakpoints in include files which contain C code. (In the past, you had to
6275 try twice in order to list an include file that you hadn't looked at before.)
6277 * Interesting infernals change
6279 GDB now deals with arbitrary numbers of sections, where the symbols for each
6280 section must be relocated relative to that section's landing place in the
6281 target's address space. This work was needed to support ELF with embedded
6282 stabs used by Solaris-2.0.
6284 * Bug fixes (of course!)
6286 There have been loads of fixes for the following things:
6287 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6288 i960, stabs, DOS(GO32), procfs, etc...
6290 See the ChangeLog for details.
6292 *** Changes in GDB-4.5:
6294 * New machines supported (host and target)
6296 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6298 SGI Irix-4.x mips-sgi-irix4 or iris4
6300 * New malloc package
6302 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6303 Mmalloc is capable of handling mutiple heaps of memory. It is also
6304 capable of saving a heap to a file, and then mapping it back in later.
6305 This can be used to greatly speedup the startup of GDB by using a
6306 pre-parsed symbol table which lives in a mmalloc managed heap. For
6307 more details, please read mmalloc/mmalloc.texi.
6311 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6312 'help info proc' for details.
6314 * MIPS ecoff symbol table format
6316 The code that reads MIPS symbol table format is now supported on all hosts.
6317 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6320 * File name changes for MS-DOS
6322 Many files in the config directories have been renamed to make it easier to
6323 support GDB on MS-DOSe systems (which have very restrictive file name
6324 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6325 environment) is close to working but has some remaining problems. Note
6326 that debugging of DOS programs is not supported, due to limitations
6327 in the ``operating system'', but it can be used to host cross-debugging.
6329 * Cross byte order fixes
6331 Many fixes have been made to support cross debugging of Sparc and MIPS
6332 targets from hosts whose byte order differs.
6334 * New -mapped and -readnow options
6336 If memory-mapped files are available on your system through the 'mmap'
6337 system call, you can use the -mapped option on the `file' or
6338 `symbol-file' commands to cause GDB to write the symbols from your
6339 program into a reusable file. If the program you are debugging is
6340 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6341 Future GDB debugging sessions will notice the presence of this file,
6342 and will quickly map in symbol information from it, rather than reading
6343 the symbol table from the executable program. Using the '-mapped'
6344 option in a GDB `file' or `symbol-file' command has the same effect as
6345 starting GDB with the '-mapped' command-line option.
6347 You can cause GDB to read the entire symbol table immediately by using
6348 the '-readnow' option with any of the commands that load symbol table
6349 information (or on the GDB command line). This makes the command
6350 slower, but makes future operations faster.
6352 The -mapped and -readnow options are typically combined in order to
6353 build a `fred.syms' file that contains complete symbol information.
6354 A simple GDB invocation to do nothing but build a `.syms' file for future
6357 gdb -batch -nx -mapped -readnow programname
6359 The `.syms' file is specific to the host machine on which GDB is run.
6360 It holds an exact image of GDB's internal symbol table. It cannot be
6361 shared across multiple host platforms.
6363 * longjmp() handling
6365 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6366 siglongjmp() without losing control. This feature has not yet been ported to
6367 all systems. It currently works on many 386 platforms, all MIPS-based
6368 platforms (SGI, DECstation, etc), and Sun3/4.
6372 Preliminary work has been put in to support the new Solaris OS from Sun. At
6373 this time, it can control and debug processes, but it is not capable of
6378 As always, many many bug fixes. The major areas were with g++, and mipsread.
6379 People using the MIPS-based platforms should experience fewer mysterious
6380 crashes and trashed symbol tables.
6382 *** Changes in GDB-4.4:
6384 * New machines supported (host and target)
6386 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6388 BSD Reno on Vax vax-dec-bsd
6389 Ultrix on Vax vax-dec-ultrix
6391 * New machines supported (target)
6393 AMD 29000 embedded, using EBMON a29k-none-none
6397 GDB continues to improve its handling of C++. `References' work better.
6398 The demangler has also been improved, and now deals with symbols mangled as
6399 per the Annotated C++ Reference Guide.
6401 GDB also now handles `stabs' symbol information embedded in MIPS
6402 `ecoff' symbol tables. Since the ecoff format was not easily
6403 extensible to handle new languages such as C++, this appeared to be a
6404 good way to put C++ debugging info into MIPS binaries. This option
6405 will be supported in the GNU C compiler, version 2, when it is
6408 * New features for SVR4
6410 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6411 shared libraries. Debugging dynamically linked programs should present
6412 only minor differences from debugging statically linked programs.
6414 The `info proc' command will print out information about any process
6415 on an SVR4 system (including the one you are debugging). At the moment,
6416 it prints the address mappings of the process.
6418 If you bring up GDB on another SVR4 system, please send mail to
6419 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6421 * Better dynamic linking support in SunOS
6423 Reading symbols from shared libraries which contain debugging symbols
6424 now works properly. However, there remain issues such as automatic
6425 skipping of `transfer vector' code during function calls, which
6426 make it harder to debug code in a shared library, than to debug the
6427 same code linked statically.
6431 GDB is now using the latest `getopt' routines from the FSF. This
6432 version accepts the -- prefix for options with long names. GDB will
6433 continue to accept the old forms (-option and +option) as well.
6434 Various single letter abbreviations for options have been explicity
6435 added to the option table so that they won't get overshadowed in the
6436 future by other options that begin with the same letter.
6440 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6441 Many assorted bugs have been handled. Many more remain to be handled.
6442 See the various ChangeLog files (primarily in gdb and bfd) for details.
6445 *** Changes in GDB-4.3:
6447 * New machines supported (host and target)
6449 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6450 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6451 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6453 * Almost SCO Unix support
6455 We had hoped to support:
6456 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6457 (except for core file support), but we discovered very late in the release
6458 that it has problems with process groups that render gdb unusable. Sorry
6459 about that. I encourage people to fix it and post the fixes.
6461 * Preliminary ELF and DWARF support
6463 GDB can read ELF object files on System V Release 4, and can handle
6464 debugging records for C, in DWARF format, in ELF files. This support
6465 is preliminary. If you bring up GDB on another SVR4 system, please
6466 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6471 GDB now uses the latest `readline' library. One user-visible change
6472 is that two tabs will list possible command completions, which previously
6473 required typing M-? (meta-question mark, or ESC ?).
6477 The `stepi' bug that many of you noticed has been squashed.
6478 Many bugs in C++ have been handled. Many more remain to be handled.
6479 See the various ChangeLog files (primarily in gdb and bfd) for details.
6481 * State of the MIPS world (in case you wondered):
6483 GDB can understand the symbol tables emitted by the compilers
6484 supplied by most vendors of MIPS-based machines, including DEC. These
6485 symbol tables are in a format that essentially nobody else uses.
6487 Some versions of gcc come with an assembler post-processor called
6488 mips-tfile. This program is required if you want to do source-level
6489 debugging of gcc-compiled programs. I believe FSF does not ship
6490 mips-tfile with gcc version 1, but it will eventually come with gcc
6493 Debugging of g++ output remains a problem. g++ version 1.xx does not
6494 really support it at all. (If you're lucky, you should be able to get
6495 line numbers and stack traces to work, but no parameters or local
6496 variables.) With some work it should be possible to improve the
6499 When gcc version 2 is released, you will have somewhat better luck.
6500 However, even then you will get confusing results for inheritance and
6503 We will eventually provide full debugging of g++ output on
6504 DECstations. This will probably involve some kind of stabs-in-ecoff
6505 encapulation, but the details have not been worked out yet.
6508 *** Changes in GDB-4.2:
6510 * Improved configuration
6512 Only one copy of `configure' exists now, and it is not self-modifying.
6513 Porting BFD is simpler.
6517 The `step' and `next' commands now only stop at the first instruction
6518 of a source line. This prevents the multiple stops that used to occur
6519 in switch statements, for-loops, etc. `Step' continues to stop if a
6520 function that has debugging information is called within the line.
6524 Lots of small bugs fixed. More remain.
6526 * New host supported (not target)
6528 Intel 386 PC clone running Mach i386-none-mach
6531 *** Changes in GDB-4.1:
6533 * Multiple source language support
6535 GDB now has internal scaffolding to handle several source languages.
6536 It determines the type of each source file from its filename extension,
6537 and will switch expression parsing and number formatting to match the
6538 language of the function in the currently selected stack frame.
6539 You can also specifically set the language to be used, with
6540 `set language c' or `set language modula-2'.
6544 GDB now has preliminary support for the GNU Modula-2 compiler,
6545 currently under development at the State University of New York at
6546 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6547 continue through the fall of 1991 and into 1992.
6549 Other Modula-2 compilers are currently not supported, and attempting to
6550 debug programs compiled with them will likely result in an error as the
6551 symbol table is read. Feel free to work on it, though!
6553 There are hooks in GDB for strict type checking and range checking,
6554 in the `Modula-2 philosophy', but they do not currently work.
6558 GDB can now write to executable and core files (e.g. patch
6559 a variable's value). You must turn this switch on, specify
6560 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6561 by assigning a new value to a variable. Modifications take
6564 * Automatic SunOS shared library reading
6566 When you run your program, GDB automatically determines where its
6567 shared libraries (if any) have been loaded, and reads their symbols.
6568 The `share' command is no longer needed. This also works when
6569 examining core files.
6573 You can specify the number of lines that the `list' command shows.
6576 * New machines supported (host and target)
6578 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6579 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6580 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6582 * New hosts supported (not targets)
6584 IBM RT/PC: romp-ibm-aix or rtpc
6586 * New targets supported (not hosts)
6588 AMD 29000 embedded with COFF a29k-none-coff
6589 AMD 29000 embedded with a.out a29k-none-aout
6590 Ultracomputer remote kernel debug a29k-nyu-kern
6592 * New remote interfaces
6598 *** Changes in GDB-4.0:
6602 Wide output is wrapped at good places to make the output more readable.
6604 Gdb now supports cross-debugging from a host machine of one type to a
6605 target machine of another type. Communication with the target system
6606 is over serial lines. The ``target'' command handles connecting to the
6607 remote system; the ``load'' command will download a program into the
6608 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6609 also supports debugging of realtime processes running under VxWorks,
6610 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6611 stub on the target system.
6613 New CPUs supported include the AMD 29000 and Intel 960.
6615 GDB now reads object files and symbol tables via a ``binary file''
6616 library, which allows a single copy of GDB to debug programs of multiple
6617 object file types such as a.out and coff.
6619 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6620 refcard.dvi and refcard.ps are available to format it).
6623 * Control-Variable user interface simplified
6625 All variables that control the operation of the debugger can be set
6626 by the ``set'' command, and displayed by the ``show'' command.
6628 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6629 ``Show prompt'' produces the response:
6630 Gdb's prompt is new-gdb=>.
6632 What follows are the NEW set commands. The command ``help set'' will
6633 print a complete list of old and new set commands. ``help set FOO''
6634 will give a longer description of the variable FOO. ``show'' will show
6635 all of the variable descriptions and their current settings.
6637 confirm on/off: Enables warning questions for operations that are
6638 hard to recover from, e.g. rerunning the program while
6639 it is already running. Default is ON.
6641 editing on/off: Enables EMACS style command line editing
6642 of input. Previous lines can be recalled with
6643 control-P, the current line can be edited with control-B,
6644 you can search for commands with control-R, etc.
6647 history filename NAME: NAME is where the gdb command history
6648 will be stored. The default is .gdb_history,
6649 or the value of the environment variable
6652 history size N: The size, in commands, of the command history. The
6653 default is 256, or the value of the environment variable
6656 history save on/off: If this value is set to ON, the history file will
6657 be saved after exiting gdb. If set to OFF, the
6658 file will not be saved. The default is OFF.
6660 history expansion on/off: If this value is set to ON, then csh-like
6661 history expansion will be performed on
6662 command line input. The default is OFF.
6664 radix N: Sets the default radix for input and output. It can be set
6665 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6666 in the current radix, so "set radix 10" is always a no-op.
6668 height N: This integer value is the number of lines on a page. Default
6669 is 24, the current `stty rows'' setting, or the ``li#''
6670 setting from the termcap entry matching the environment
6673 width N: This integer value is the number of characters on a line.
6674 Default is 80, the current `stty cols'' setting, or the ``co#''
6675 setting from the termcap entry matching the environment
6678 Note: ``set screensize'' is obsolete. Use ``set height'' and
6679 ``set width'' instead.
6681 print address on/off: Print memory addresses in various command displays,
6682 such as stack traces and structure values. Gdb looks
6683 more ``symbolic'' if you turn this off; it looks more
6684 ``machine level'' with it on. Default is ON.
6686 print array on/off: Prettyprint arrays. New convenient format! Default
6689 print demangle on/off: Print C++ symbols in "source" form if on,
6692 print asm-demangle on/off: Same, for assembler level printouts
6695 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6698 * Support for Epoch Environment.
6700 The epoch environment is a version of Emacs v18 with windowing. One
6701 new command, ``inspect'', is identical to ``print'', except that if you
6702 are running in the epoch environment, the value is printed in its own
6706 * Support for Shared Libraries
6708 GDB can now debug programs and core files that use SunOS shared libraries.
6709 Symbols from a shared library cannot be referenced
6710 before the shared library has been linked with the program (this
6711 happens after you type ``run'' and before the function main() is entered).
6712 At any time after this linking (including when examining core files
6713 from dynamically linked programs), gdb reads the symbols from each
6714 shared library when you type the ``sharedlibrary'' command.
6715 It can be abbreviated ``share''.
6717 sharedlibrary REGEXP: Load shared object library symbols for files
6718 matching a unix regular expression. No argument
6719 indicates to load symbols for all shared libraries.
6721 info sharedlibrary: Status of loaded shared libraries.
6726 A watchpoint stops execution of a program whenever the value of an
6727 expression changes. Checking for this slows down execution
6728 tremendously whenever you are in the scope of the expression, but is
6729 quite useful for catching tough ``bit-spreader'' or pointer misuse
6730 problems. Some machines such as the 386 have hardware for doing this
6731 more quickly, and future versions of gdb will use this hardware.
6733 watch EXP: Set a watchpoint (breakpoint) for an expression.
6735 info watchpoints: Information about your watchpoints.
6737 delete N: Deletes watchpoint number N (same as breakpoints).
6738 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6739 enable N: Re-enables watchpoint number N (same as breakpoints).
6742 * C++ multiple inheritance
6744 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6747 * C++ exception handling
6749 Gdb now supports limited C++ exception handling. Besides the existing
6750 ability to breakpoint on an exception handler, gdb can breakpoint on
6751 the raising of an exception (before the stack is peeled back to the
6754 catch FOO: If there is a FOO exception handler in the dynamic scope,
6755 set a breakpoint to catch exceptions which may be raised there.
6756 Multiple exceptions (``catch foo bar baz'') may be caught.
6758 info catch: Lists all exceptions which may be caught in the
6759 current stack frame.
6762 * Minor command changes
6764 The command ``call func (arg, arg, ...)'' now acts like the print
6765 command, except it does not print or save a value if the function's result
6766 is void. This is similar to dbx usage.
6768 The ``up'' and ``down'' commands now always print the frame they end up
6769 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6770 frames without printing.
6772 * New directory command
6774 'dir' now adds directories to the FRONT of the source search path.
6775 The path starts off empty. Source files that contain debug information
6776 about the directory in which they were compiled can be found even
6777 with an empty path; Sun CC and GCC include this information. If GDB can't
6778 find your source file in the current directory, type "dir .".
6780 * Configuring GDB for compilation
6782 For normal use, type ``./configure host''. See README or gdb.texinfo
6785 GDB now handles cross debugging. If you are remotely debugging between
6786 two different machines, type ``./configure host -target=targ''.
6787 Host is the machine where GDB will run; targ is the machine
6788 where the program that you are debugging will run.