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
97 FreeBSD/aarch64 aarch64*-*-freebsd*
99 *** Changes in GDB 8.0
101 * GDB now supports access to the PKU register on GNU/Linux. The register is
102 added by the Memory Protection Keys for Userspace feature which will be
103 available in future Intel CPUs.
105 * GDB now supports C++11 rvalue references.
109 ** New functions to start, stop and access a running btrace recording.
110 ** Rvalue references are now supported in gdb.Type.
112 * GDB now supports recording and replaying rdrand and rdseed Intel 64
115 * Building GDB and GDBserver now requires a C++11 compiler.
117 For example, GCC 4.8 or later.
119 It is no longer possible to build GDB or GDBserver with a C
120 compiler. The --disable-build-with-cxx configure option has been
123 * Building GDB and GDBserver now requires GNU make >= 3.81.
125 It is no longer supported to build GDB or GDBserver with another
126 implementation of the make program or an earlier version of GNU make.
128 * Native debugging on MS-Windows supports command-line redirection
130 Command-line arguments used for starting programs on MS-Windows can
131 now include redirection symbols supported by native Windows shells,
132 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
133 as "run", "start", and "set args", as well as the corresponding MI
136 * Support for thread names on MS-Windows.
138 GDB now catches and handles the special exception that programs
139 running on MS-Windows use to assign names to threads in the
142 * Support for Java programs compiled with gcj has been removed.
144 * User commands now accept an unlimited number of arguments.
145 Previously, only up to 10 was accepted.
147 * The "eval" command now expands user-defined command arguments.
149 This makes it easier to process a variable number of arguments:
154 eval "print $arg%d", $i
159 * Target descriptions can now describe registers for sparc32 and sparc64.
161 * GDB now supports DWARF version 5 (debug information format).
162 Its .debug_names index is not yet supported.
164 * New native configurations
166 FreeBSD/mips mips*-*-freebsd
170 Synopsys ARC arc*-*-elf32
171 FreeBSD/mips mips*-*-freebsd
173 * Removed targets and native configurations
175 Alpha running FreeBSD alpha*-*-freebsd*
176 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
181 Erases all the flash memory regions reported by the target.
183 maint print arc arc-instruction address
184 Print internal disassembler information about instruction at a given address.
188 set disassembler-options
189 show disassembler-options
190 Controls the passing of target specific information to the disassembler.
191 If it is necessary to specify more than one disassembler option then
192 multiple options can be placed together into a comma separated list.
193 The default value is the empty string. Currently, the only supported
194 targets are ARM, PowerPC and S/390.
199 Erases all the flash memory regions reported by the target. This is
200 equivalent to the CLI command flash-erase.
202 -file-list-shared-libraries
203 List the shared libraries in the program. This is
204 equivalent to the CLI command "info shared".
206 *** Changes in GDB 7.12
208 * GDB and GDBserver now build with a C++ compiler by default.
210 The --enable-build-with-cxx configure option is now enabled by
211 default. One must now explicitly configure with
212 --disable-build-with-cxx in order to build with a C compiler. This
213 option will be removed in a future release.
215 * GDBserver now supports recording btrace without maintaining an active
218 * GDB now supports a negative repeat count in the 'x' command to examine
219 memory backward from the given address. For example:
222 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
223 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
224 (gdb) x/-5i 0x0000000000400580
225 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
226 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
227 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
228 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
229 0x40057b <main(int, char**)+25>:
230 callq 0x400536 <Func1(int, char const*)>
232 * Fortran: Support structures with fields of dynamic types and
233 arrays of dynamic types.
235 * The symbol dumping maintenance commands have new syntax.
236 maint print symbols [-pc address] [--] [filename]
237 maint print symbols [-objfile objfile] [-source source] [--] [filename]
238 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
239 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
240 maint print msymbols [-objfile objfile] [--] [filename]
242 * GDB now supports multibit bitfields and enums in target register
245 * New Python-based convenience function $_as_string(val), which returns
246 the textual representation of a value. This function is especially
247 useful to obtain the text label of an enum value.
249 * Intel MPX bound violation handling.
251 Segmentation faults caused by a Intel MPX boundary violation
252 now display the kind of violation (upper or lower), the memory
253 address accessed and the memory bounds, along with the usual
254 signal received and code location.
258 Program received signal SIGSEGV, Segmentation fault
259 Upper bound violation while accessing address 0x7fffffffc3b3
260 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
261 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
263 * Rust language support.
264 GDB now supports debugging programs written in the Rust programming
265 language. See https://www.rust-lang.org/ for more information about
268 * Support for running interpreters on specified input/output devices
270 GDB now supports a new mechanism that allows frontends to provide
271 fully featured GDB console views, as a better alternative to
272 building such views on top of the "-interpreter-exec console"
273 command. See the new "new-ui" command below. With that command,
274 frontends can now start GDB in the traditional command-line mode
275 running in an embedded terminal emulator widget, and create a
276 separate MI interpreter running on a specified i/o device. In this
277 way, GDB handles line editing, history, tab completion, etc. in the
278 console all by itself, and the GUI uses the separate MI interpreter
279 for its own control and synchronization, invisible to the command
282 * The "catch syscall" command catches groups of related syscalls.
284 The "catch syscall" command now supports catching a group of related
285 syscalls using the 'group:' or 'g:' prefix.
290 skip -gfile file-glob-pattern
291 skip -function function
292 skip -rfunction regular-expression
293 A generalized form of the skip command, with new support for
294 glob-style file names and regular expressions for function names.
295 Additionally, a file spec and a function spec may now be combined.
297 maint info line-table REGEXP
298 Display the contents of GDB's internal line table data struture.
301 Run any GDB unit tests that were compiled in.
304 Start a new user interface instance running INTERP as interpreter,
305 using the TTY file for input/output.
309 ** gdb.Breakpoint objects have a new attribute "pending", which
310 indicates whether the breakpoint is pending.
311 ** Three new breakpoint-related events have been added:
312 gdb.breakpoint_created, gdb.breakpoint_modified, and
313 gdb.breakpoint_deleted.
316 Signal ("set") the given MS-Windows event object. This is used in
317 conjunction with the Windows JIT debugging (AeDebug) support, where
318 the OS suspends a crashing process until a debugger can attach to
319 it. Resuming the crashing process, in order to debug it, is done by
322 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
323 was added in GDBserver, including JIT compiling fast tracepoint's
324 conditional expression bytecode into native code.
326 * Support for various remote target protocols and ROM monitors has
329 target m32rsdi Remote M32R debugging over SDI
330 target mips MIPS remote debugging protocol
331 target pmon PMON ROM monitor
332 target ddb NEC's DDB variant of PMON for Vr4300
333 target rockhopper NEC RockHopper variant of PMON
334 target lsi LSI variant of PMO
336 * Support for tracepoints and fast tracepoints on powerpc-linux,
337 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
338 including JIT compiling fast tracepoint's conditional expression
339 bytecode into native code.
341 * MI async record =record-started now includes the method and format used for
342 recording. For example:
344 =record-started,thread-group="i1",method="btrace",format="bts"
346 * MI async record =thread-selected now includes the frame field. For example:
348 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
352 Andes NDS32 nds32*-*-elf
354 *** Changes in GDB 7.11
356 * GDB now supports debugging kernel-based threads on FreeBSD.
358 * Per-inferior thread numbers
360 Thread numbers are now per inferior instead of global. If you're
361 debugging multiple inferiors, GDB displays thread IDs using a
362 qualified INF_NUM.THR_NUM form. For example:
366 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
367 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
368 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
369 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
371 As consequence, thread numbers as visible in the $_thread
372 convenience variable and in Python's InferiorThread.num attribute
373 are no longer unique between inferiors.
375 GDB now maintains a second thread ID per thread, referred to as the
376 global thread ID, which is the new equivalent of thread numbers in
377 previous releases. See also $_gthread below.
379 For backwards compatibility, MI's thread IDs always refer to global
382 * Commands that accept thread IDs now accept the qualified
383 INF_NUM.THR_NUM form as well. For example:
386 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
389 * In commands that accept a list of thread IDs, you can now refer to
390 all threads of an inferior using a star wildcard. GDB accepts
391 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
392 refer to all threads of the current inferior. For example, "info
395 * You can use "info threads -gid" to display the global thread ID of
398 * The new convenience variable $_gthread holds the global number of
401 * The new convenience variable $_inferior holds the number of the
404 * GDB now displays the ID and name of the thread that hit a breakpoint
405 or received a signal, if your program is multi-threaded. For
408 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
409 Thread 1 "main" received signal SIGINT, Interrupt.
411 * Record btrace now supports non-stop mode.
413 * Support for tracepoints on aarch64-linux was added in GDBserver.
415 * The 'record instruction-history' command now indicates speculative execution
416 when using the Intel Processor Trace recording format.
418 * GDB now allows users to specify explicit locations, bypassing
419 the linespec parser. This feature is also available to GDB/MI
422 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
423 GDB now is able to debug both AArch64 applications and ARM applications
426 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
427 including JIT compiling fast tracepoint's conditional expression bytecode
430 * GDB now supports displaced stepping on AArch64 GNU/Linux.
432 * "info threads", "info inferiors", "info display", "info checkpoints"
433 and "maint info program-spaces" now list the corresponding items in
434 ascending ID order, for consistency with all other "info" commands.
436 * In Ada, the overloads selection menu has been enhanced to display the
437 parameter types and the return types for the matching overloaded subprograms.
441 maint set target-non-stop (on|off|auto)
442 maint show target-non-stop
443 Control whether GDB targets always operate in non-stop mode even if
444 "set non-stop" is "off". The default is "auto", meaning non-stop
445 mode is enabled if supported by the target.
447 maint set bfd-sharing
448 maint show bfd-sharing
449 Control the reuse of bfd objects.
453 Control display of debugging info regarding bfd caching.
457 Control display of debugging info regarding FreeBSD threads.
459 set remote multiprocess-extensions-packet
460 show remote multiprocess-extensions-packet
461 Set/show the use of the remote protocol multiprocess extensions.
463 set remote thread-events
464 show remote thread-events
465 Set/show the use of thread create/exit events.
467 set ada print-signatures on|off
468 show ada print-signatures"
469 Control whether parameter types and return types are displayed in overloads
470 selection menus. It is activaled (@code{on}) by default.
474 Controls the maximum size of memory, in bytes, that GDB will
475 allocate for value contents. Prevents incorrect programs from
476 causing GDB to allocate overly large buffers. Default is 64k.
478 * The "disassemble" command accepts a new modifier: /s.
479 It prints mixed source+disassembly like /m with two differences:
480 - disassembled instructions are now printed in program order, and
481 - and source for all relevant files is now printed.
482 The "/m" option is now considered deprecated: its "source-centric"
483 output hasn't proved useful in practice.
485 * The "record instruction-history" command accepts a new modifier: /s.
486 It behaves exactly like /m and prints mixed source+disassembly.
488 * The "set scheduler-locking" command supports a new mode "replay".
489 It behaves like "off" in record mode and like "on" in replay mode.
491 * Support for various ROM monitors has been removed:
493 target dbug dBUG ROM monitor for Motorola ColdFire
494 target picobug Motorola picobug monitor
495 target dink32 DINK32 ROM monitor for PowerPC
496 target m32r Renesas M32R/D ROM monitor
497 target mon2000 mon2000 ROM monitor
498 target ppcbug PPCBUG ROM monitor for PowerPC
500 * Support for reading/writing memory and extracting values on architectures
501 whose memory is addressable in units of any integral multiple of 8 bits.
506 Indicates whether the inferior must be started with a shell or not.
509 Indicates that an exec system call was executed.
511 exec-events feature in qSupported
512 The qSupported packet allows GDB to request support for exec
513 events using the new 'gdbfeature' exec-event, and the qSupported
514 response can contain the corresponding 'stubfeature'. Set and
515 show commands can be used to display whether these features are enabled.
518 Equivalent to interrupting with the ^C character, but works in
521 thread created stop reason (T05 create:...)
522 Indicates that the thread was just created and is stopped at entry.
524 thread exit stop reply (w exitcode;tid)
525 Indicates that the thread has terminated.
528 Enables/disables thread create and exit event reporting. For
529 example, this is used in non-stop mode when GDB stops a set of
530 threads and synchronously waits for the their corresponding stop
531 replies. Without exit events, if one of the threads exits, GDB
532 would hang forever not knowing that it should no longer expect a
533 stop for that same thread.
536 Indicates that there are no resumed threads left in the target (all
537 threads are stopped). The remote stub reports support for this stop
538 reply to GDB's qSupported query.
541 Enables/disables catching syscalls from the inferior process.
542 The remote stub reports support for this packet to GDB's qSupported query.
544 syscall_entry stop reason
545 Indicates that a syscall was just called.
547 syscall_return stop reason
548 Indicates that a syscall just returned.
550 * Extended-remote exec events
552 ** GDB now has support for exec events on extended-remote Linux targets.
553 For such targets with Linux kernels 2.5.46 and later, this enables
554 follow-exec-mode and exec catchpoints.
556 set remote exec-event-feature-packet
557 show remote exec-event-feature-packet
558 Set/show the use of the remote exec event feature.
560 * Thread names in remote protocol
562 The reply to qXfer:threads:read may now include a name attribute for each
565 * Target remote mode fork and exec events
567 ** GDB now has support for fork and exec events on target remote mode
568 Linux targets. For such targets with Linux kernels 2.5.46 and later,
569 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
570 fork and exec catchpoints.
572 * Remote syscall events
574 ** GDB now has support for catch syscall on remote Linux targets,
575 currently enabled on x86/x86_64 architectures.
577 set remote catch-syscall-packet
578 show remote catch-syscall-packet
579 Set/show the use of the remote catch syscall feature.
583 ** The -var-set-format command now accepts the zero-hexadecimal
584 format. It outputs data in hexadecimal format with zero-padding on the
589 ** gdb.InferiorThread objects have a new attribute "global_num",
590 which refers to the thread's global thread ID. The existing
591 "num" attribute now refers to the thread's per-inferior number.
592 See "Per-inferior thread numbers" above.
593 ** gdb.InferiorThread objects have a new attribute "inferior", which
594 is the Inferior object the thread belongs to.
596 *** Changes in GDB 7.10
598 * Support for process record-replay and reverse debugging on aarch64*-linux*
599 targets has been added. GDB now supports recording of A64 instruction set
600 including advance SIMD instructions.
602 * Support for Sun's version of the "stabs" debug file format has been removed.
604 * GDB now honors the content of the file /proc/PID/coredump_filter
605 (PID is the process ID) on GNU/Linux systems. This file can be used
606 to specify the types of memory mappings that will be included in a
607 corefile. For more information, please refer to the manual page of
608 "core(5)". GDB also has a new command: "set use-coredump-filter
609 on|off". It allows to set whether GDB will read the content of the
610 /proc/PID/coredump_filter file when generating a corefile.
612 * The "info os" command on GNU/Linux can now display information on
614 "info os cpus" Listing of all cpus/cores on the system
616 * GDB has two new commands: "set serial parity odd|even|none" and
617 "show serial parity". These allows to set or show parity for the
620 * The "info source" command now displays the producer string if it was
621 present in the debug info. This typically includes the compiler version
622 and may include things like its command line arguments.
624 * The "info dll", an alias of the "info sharedlibrary" command,
625 is now available on all platforms.
627 * Directory names supplied to the "set sysroot" commands may be
628 prefixed with "target:" to tell GDB to access shared libraries from
629 the target system, be it local or remote. This replaces the prefix
630 "remote:". The default sysroot has been changed from "" to
631 "target:". "remote:" is automatically converted to "target:" for
632 backward compatibility.
634 * The system root specified by "set sysroot" will be prepended to the
635 filename of the main executable (if reported to GDB as absolute by
636 the operating system) when starting processes remotely, and when
637 attaching to already-running local or remote processes.
639 * GDB now supports automatic location and retrieval of executable
640 files from remote targets. Remote debugging can now be initiated
641 using only a "target remote" or "target extended-remote" command
642 (no "set sysroot" or "file" commands are required). See "New remote
645 * The "dump" command now supports verilog hex format.
647 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
649 * On GNU/Linux, GDB and gdbserver are now able to access executable
650 and shared library files without a "set sysroot" command when
651 attaching to processes running in different mount namespaces from
652 the debugger. This makes it possible to attach to processes in
653 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
654 See "New remote packets" below.
656 * The "tui reg" command now provides completion for all of the
657 available register groups, including target specific groups.
659 * The HISTSIZE environment variable is no longer read when determining
660 the size of GDB's command history. GDB now instead reads the dedicated
661 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
662 disables truncation of command history. Non-numeric values of GDBHISTSIZE
667 ** Memory ports can now be unbuffered.
671 ** gdb.Objfile objects have a new attribute "username",
672 which is the name of the objfile as specified by the user,
673 without, for example, resolving symlinks.
674 ** You can now write frame unwinders in Python.
675 ** gdb.Type objects have a new method "optimized_out",
676 returning optimized out gdb.Value instance of this type.
677 ** gdb.Value objects have new methods "reference_value" and
678 "const_value" which return a reference to the value and a
679 "const" version of the value respectively.
683 maint print symbol-cache
684 Print the contents of the symbol cache.
686 maint print symbol-cache-statistics
687 Print statistics of symbol cache usage.
689 maint flush-symbol-cache
690 Flush the contents of the symbol cache.
694 Start branch trace recording using Branch Trace Store (BTS) format.
697 Evaluate expression by using the compiler and print result.
701 Explicit commands for enabling and disabling tui mode.
704 set mpx bound on i386 and amd64
705 Support for bound table investigation on Intel MPX enabled applications.
709 Start branch trace recording using Intel Processor Trace format.
712 Print information about branch tracing internals.
714 maint btrace packet-history
715 Print the raw branch tracing data.
717 maint btrace clear-packet-history
718 Discard the stored raw branch tracing data.
721 Discard all branch tracing data. It will be fetched and processed
722 anew by the next "record" command.
727 Renamed from "set debug dwarf2-die".
729 Renamed from "show debug dwarf2-die".
732 Renamed from "set debug dwarf2-read".
733 show debug dwarf-read
734 Renamed from "show debug dwarf2-read".
736 maint set dwarf always-disassemble
737 Renamed from "maint set dwarf2 always-disassemble".
738 maint show dwarf always-disassemble
739 Renamed from "maint show dwarf2 always-disassemble".
741 maint set dwarf max-cache-age
742 Renamed from "maint set dwarf2 max-cache-age".
743 maint show dwarf max-cache-age
744 Renamed from "maint show dwarf2 max-cache-age".
747 show debug dwarf-line
748 Control display of debugging info regarding DWARF line processing.
752 Set the maximum number of candidates to be considered during
753 completion. The default value is 200. This limit allows GDB
754 to avoid generating large completion lists, the computation of
755 which can cause the debugger to become temporarily unresponsive.
757 set history remove-duplicates
758 show history remove-duplicates
759 Control the removal of duplicate history entries.
761 maint set symbol-cache-size
762 maint show symbol-cache-size
763 Control the size of the symbol cache.
765 set|show record btrace bts buffer-size
766 Set and show the size of the ring buffer used for branch tracing in
768 The obtained size may differ from the requested size. Use "info
769 record" to see the obtained buffer size.
771 set debug linux-namespaces
772 show debug linux-namespaces
773 Control display of debugging info regarding Linux namespaces.
775 set|show record btrace pt buffer-size
776 Set and show the size of the ring buffer used for branch tracing in
777 Intel Processor Trace format.
778 The obtained size may differ from the requested size. Use "info
779 record" to see the obtained buffer size.
781 maint set|show btrace pt skip-pad
782 Set and show whether PAD packets are skipped when computing the
785 * The command 'thread apply all' can now support new option '-ascending'
786 to call its specified command for all threads in ascending order.
788 * Python/Guile scripting
790 ** GDB now supports auto-loading of Python/Guile scripts contained in the
791 special section named `.debug_gdb_scripts'.
795 qXfer:btrace-conf:read
796 Return the branch trace configuration for the current thread.
798 Qbtrace-conf:bts:size
799 Set the requested ring buffer size for branch tracing in BTS format.
802 Enable Intel Procesor Trace-based branch tracing for the current
803 process. The remote stub reports support for this packet to GDB's
807 Set the requested ring buffer size for branch tracing in Intel Processor
811 Indicates a memory breakpoint instruction was executed, irrespective
812 of whether it was GDB that planted the breakpoint or the breakpoint
813 is hardcoded in the program. This is required for correct non-stop
817 Indicates the target stopped for a hardware breakpoint. This is
818 required for correct non-stop mode operation.
821 Return information about files on the remote system.
824 Return the full absolute name of the file that was executed to
825 create a process running on the remote system.
828 Select the filesystem on which vFile: operations with filename
829 arguments will operate. This is required for GDB to be able to
830 access files on remote targets where the remote stub does not
831 share a common filesystem with the inferior(s).
834 Indicates that a fork system call was executed.
837 Indicates that a vfork system call was executed.
839 vforkdone stop reason
840 Indicates that a vfork child of the specified process has executed
841 an exec or exit, allowing the vfork parent to resume execution.
843 fork-events and vfork-events features in qSupported
844 The qSupported packet allows GDB to request support for fork and
845 vfork events using new 'gdbfeatures' fork-events and vfork-events,
846 and the qSupported response can contain the corresponding
847 'stubfeatures'. Set and show commands can be used to display
848 whether these features are enabled.
850 * Extended-remote fork events
852 ** GDB now has support for fork events on extended-remote Linux
853 targets. For targets with Linux kernels 2.5.60 and later, this
854 enables follow-fork-mode and detach-on-fork for both fork and
855 vfork, as well as fork and vfork catchpoints.
857 * The info record command now shows the recording format and the
858 branch tracing configuration for the current thread when using
859 the btrace record target.
860 For the BTS format, it shows the ring buffer size.
862 * GDB now has support for DTrace USDT (Userland Static Defined
863 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
865 * GDB now supports access to vector registers on S/390 GNU/Linux
868 * Removed command line options
870 -xdb HP-UX XDB compatibility mode.
872 * Removed targets and native configurations
874 HP/PA running HP-UX hppa*-*-hpux*
875 Itanium running HP-UX ia64-*-hpux*
877 * New configure options
880 This configure option allows the user to build GDB with support for
881 Intel Processor Trace (default: auto). This requires libipt.
883 --with-libipt-prefix=PATH
884 Specify the path to the version of libipt that GDB should use.
885 $PATH/include should contain the intel-pt.h header and
886 $PATH/lib should contain the libipt.so library.
888 *** Changes in GDB 7.9.1
892 ** Xmethods can now specify a result type.
894 *** Changes in GDB 7.9
896 * GDB now supports hardware watchpoints on x86 GNU Hurd.
900 ** You can now access frame registers from Python scripts.
901 ** New attribute 'producer' for gdb.Symtab objects.
902 ** gdb.Objfile objects have a new attribute "progspace",
903 which is the gdb.Progspace object of the containing program space.
904 ** gdb.Objfile objects have a new attribute "owner".
905 ** gdb.Objfile objects have a new attribute "build_id",
906 which is the build ID generated when the file was built.
907 ** gdb.Objfile objects have a new method "add_separate_debug_file".
908 ** A new event "gdb.clear_objfiles" has been added, triggered when
909 selecting a new file to debug.
910 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
911 ** New function gdb.lookup_objfile.
913 New events which are triggered when GDB modifies the state of the
916 ** gdb.events.inferior_call_pre: Function call is about to be made.
917 ** gdb.events.inferior_call_post: Function call has just been made.
918 ** gdb.events.memory_changed: A memory location has been altered.
919 ** gdb.events.register_changed: A register has been altered.
921 * New Python-based convenience functions:
923 ** $_caller_is(name [, number_of_frames])
924 ** $_caller_matches(regexp [, number_of_frames])
925 ** $_any_caller_is(name [, number_of_frames])
926 ** $_any_caller_matches(regexp [, number_of_frames])
928 * GDB now supports the compilation and injection of source code into
929 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
930 to compile the source code to object code, and if successful, inject
931 and execute that code within the current context of the inferior.
932 Currently the C language is supported. The commands used to
933 interface with this new feature are:
935 compile code [-raw|-r] [--] [source code]
936 compile file [-raw|-r] filename
940 demangle [-l language] [--] name
941 Demangle "name" in the specified language, or the current language
942 if elided. This command is renamed from the "maint demangle" command.
943 The latter is kept as a no-op to avoid "maint demangle" being interpreted
944 as "maint demangler-warning".
946 queue-signal signal-name-or-number
947 Queue a signal to be delivered to the thread when it is resumed.
949 add-auto-load-scripts-directory directory
950 Add entries to the list of directories from which to load auto-loaded
953 maint print user-registers
954 List all currently available "user" registers.
956 compile code [-r|-raw] [--] [source code]
957 Compile, inject, and execute in the inferior the executable object
958 code produced by compiling the provided source code.
960 compile file [-r|-raw] filename
961 Compile and inject into the inferior the executable object code
962 produced by compiling the source code stored in the filename
965 * On resume, GDB now always passes the signal the program had stopped
966 for to the thread the signal was sent to, even if the user changed
967 threads before resuming. Previously GDB would often (but not
968 always) deliver the signal to the thread that happens to be current
971 * Conversely, the "signal" command now consistently delivers the
972 requested signal to the current thread. GDB now asks for
973 confirmation if the program had stopped for a signal and the user
974 switched threads meanwhile.
976 * "breakpoint always-inserted" modes "off" and "auto" merged.
978 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
979 won't remove breakpoints from the target until all threads stop,
980 even in non-stop mode. The "auto" mode has been removed, and "off"
981 is now the default mode.
985 set debug symbol-lookup
986 show debug symbol-lookup
987 Control display of debugging info regarding symbol lookup.
991 ** The -list-thread-groups command outputs an exit-code field for
992 inferiors that have exited.
996 MIPS SDE mips*-sde*-elf*
1000 Support for these obsolete configurations has been removed.
1002 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
1003 SGI Irix-5.x mips-*-irix5*
1004 SGI Irix-6.x mips-*-irix6*
1005 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
1006 VAX running Ultrix vax-*-ultrix*
1008 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1009 and "assf"), have been removed. Use the "sharedlibrary" command, or
1010 its alias "share", instead.
1012 *** Changes in GDB 7.8
1014 * New command line options
1017 This is an alias for the --data-directory option.
1019 * GDB supports printing and modifying of variable length automatic arrays
1020 as specified in ISO C99.
1022 * The ARM simulator now supports instruction level tracing
1023 with or without disassembly.
1027 GDB now has support for scripting using Guile. Whether this is
1028 available is determined at configure time.
1029 Guile version 2.0 or greater is required.
1030 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
1032 * New commands (for set/show, see "New options" below)
1036 Invoke CODE by passing it to the Guile interpreter.
1040 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
1042 info auto-load guile-scripts [regexp]
1043 Print the list of automatically loaded Guile scripts.
1045 * The source command is now capable of sourcing Guile scripts.
1046 This feature is dependent on the debugger being built with Guile support.
1050 set print symbol-loading (off|brief|full)
1051 show print symbol-loading
1052 Control whether to print informational messages when loading symbol
1053 information for a file. The default is "full", but when debugging
1054 programs with large numbers of shared libraries the amount of output
1055 becomes less useful.
1057 set guile print-stack (none|message|full)
1058 show guile print-stack
1059 Show a stack trace when an error is encountered in a Guile script.
1061 set auto-load guile-scripts (on|off)
1062 show auto-load guile-scripts
1063 Control auto-loading of Guile script files.
1065 maint ada set ignore-descriptive-types (on|off)
1066 maint ada show ignore-descriptive-types
1067 Control whether the debugger should ignore descriptive types in Ada
1068 programs. The default is not to ignore the descriptive types. See
1069 the user manual for more details on descriptive types and the intended
1070 usage of this option.
1072 set auto-connect-native-target
1074 Control whether GDB is allowed to automatically connect to the
1075 native target for the run, attach, etc. commands when not connected
1076 to any target yet. See also "target native" below.
1078 set record btrace replay-memory-access (read-only|read-write)
1079 show record btrace replay-memory-access
1080 Control what memory accesses are allowed during replay.
1082 maint set target-async (on|off)
1083 maint show target-async
1084 This controls whether GDB targets operate in synchronous or
1085 asynchronous mode. Normally the default is asynchronous, if it is
1086 available; but this can be changed to more easily debug problems
1087 occurring only in synchronous mode.
1089 set mi-async (on|off)
1091 Control whether MI asynchronous mode is preferred. This supersedes
1092 "set target-async" of previous GDB versions.
1094 * "set target-async" is deprecated as a CLI option and is now an alias
1095 for "set mi-async" (only puts MI into async mode).
1097 * Background execution commands (e.g., "c&", "s&", etc.) are now
1098 possible ``out of the box'' if the target supports them. Previously
1099 the user would need to explicitly enable the possibility with the
1100 "set target-async on" command.
1102 * New features in the GDB remote stub, GDBserver
1104 ** New option --debug-format=option1[,option2,...] allows one to add
1105 additional text to each output. At present only timestamps
1106 are supported: --debug-format=timestamps.
1107 Timestamps can also be turned on with the
1108 "monitor set debug-format timestamps" command from GDB.
1110 * The 'record instruction-history' command now starts counting instructions
1111 at one. This also affects the instruction ranges reported by the
1112 'record function-call-history' command when given the /i modifier.
1114 * The command 'record function-call-history' supports a new modifier '/c' to
1115 indent the function names based on their call stack depth.
1116 The fields for the '/i' and '/l' modifier have been reordered.
1117 The source line range is now prefixed with 'at'.
1118 The instruction range is now prefixed with 'inst'.
1119 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1120 "record instruction-history" and "list" commands.
1122 * The ranges given as arguments to the 'record function-call-history' and
1123 'record instruction-history' commands are now inclusive.
1125 * The btrace record target now supports the 'record goto' command.
1126 For locations inside the execution trace, the back trace is computed
1127 based on the information stored in the execution trace.
1129 * The btrace record target supports limited reverse execution and replay.
1130 The target does not record data and therefore does not allow reading
1131 memory or registers.
1133 * The "catch syscall" command now works on s390*-linux* targets.
1135 * The "compare-sections" command is no longer specific to target
1136 remote. It now works with all targets.
1138 * All native targets are now consistently called "native".
1139 Consequently, the "target child", "target GNU", "target djgpp",
1140 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1141 commands have been replaced with "target native". The QNX/NTO port
1142 leaves the "procfs" target in place and adds a "native" target for
1143 consistency with other ports. The impact on users should be minimal
1144 as these commands previously either throwed an error, or were
1145 no-ops. The target's name is visible in the output of the following
1146 commands: "help target", "info target", "info files", "maint print
1149 * The "target native" command now connects to the native target. This
1150 can be used to launch native programs even when "set
1151 auto-connect-native-target" is set to off.
1153 * GDB now supports access to Intel MPX registers on GNU/Linux.
1155 * Support for Intel AVX-512 registers on GNU/Linux.
1156 Support displaying and modifying Intel AVX-512 registers
1157 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1159 * New remote packets
1161 qXfer:btrace:read's annex
1162 The qXfer:btrace:read packet supports a new annex 'delta' to read
1163 branch trace incrementally.
1167 ** Valid Python operations on gdb.Value objects representing
1168 structs/classes invoke the corresponding overloaded operators if
1170 ** New `Xmethods' feature in the Python API. Xmethods are
1171 additional methods or replacements for existing methods of a C++
1172 class. This feature is useful for those cases where a method
1173 defined in C++ source code could be inlined or optimized out by
1174 the compiler, making it unavailable to GDB.
1177 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1179 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1180 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1181 its alias "share", instead.
1183 * The commands "set remotebaud" and "show remotebaud" are no longer
1184 supported. Use "set serial baud" and "show serial baud" (respectively)
1189 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1190 target-async". The latter is left as a deprecated alias of the
1191 former for backward compatibility. If the target supports it,
1192 CLI background execution commands are now always possible by
1193 default, independently of whether the frontend stated a
1194 preference for asynchronous execution with "-gdb-set mi-async".
1195 Previously "-gdb-set target-async off" affected both MI execution
1196 commands and CLI execution commands.
1198 *** Changes in GDB 7.7
1200 * Improved support for process record-replay and reverse debugging on
1201 arm*-linux* targets. Support for thumb32 and syscall instruction
1202 recording has been added.
1204 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1206 * GDB now supports Fission DWP file format version 2.
1207 http://gcc.gnu.org/wiki/DebugFission
1209 * New convenience function "$_isvoid", to check whether an expression
1210 is void. A void expression is an expression where the type of the
1211 result is "void". For example, some convenience variables may be
1212 "void" when evaluated (e.g., "$_exitcode" before the execution of
1213 the program being debugged; or an undefined convenience variable).
1214 Another example, when calling a function whose return type is
1217 * The "maintenance print objfiles" command now takes an optional regexp.
1219 * The "catch syscall" command now works on arm*-linux* targets.
1221 * GDB now consistently shows "<not saved>" when printing values of
1222 registers the debug info indicates have not been saved in the frame
1223 and there's nowhere to retrieve them from
1224 (callee-saved/call-clobbered registers):
1229 (gdb) info registers rax
1232 Before, the former would print "<optimized out>", and the latter
1233 "*value not available*".
1235 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1240 ** Frame filters and frame decorators have been added.
1241 ** Temporary breakpoints are now supported.
1242 ** Line tables representation has been added.
1243 ** New attribute 'parent_type' for gdb.Field objects.
1244 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1245 ** New attribute 'name' for gdb.Type objects.
1249 Nios II ELF nios2*-*-elf
1250 Nios II GNU/Linux nios2*-*-linux
1251 Texas Instruments MSP430 msp430*-*-elf
1253 * Removed native configurations
1255 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1256 been removed. ELF variants of these configurations are kept supported.
1258 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1259 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1260 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1261 i[34567]86-*-openbsd3.[0-3]
1262 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1263 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1264 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1268 Like "catch throw", but catches a re-thrown exception.
1269 maint check-psymtabs
1270 Renamed from old "maint check-symtabs".
1272 Perform consistency checks on symtabs.
1273 maint expand-symtabs
1274 Expand symtabs matching an optional regexp.
1277 Display the details of GDB configure-time options.
1279 maint set|show per-command
1280 maint set|show per-command space
1281 maint set|show per-command time
1282 maint set|show per-command symtab
1283 Enable display of per-command gdb resource usage.
1285 remove-symbol-file FILENAME
1286 remove-symbol-file -a ADDRESS
1287 Remove a symbol file added via add-symbol-file. The file to remove
1288 can be identified by its filename or by an address that lies within
1289 the boundaries of this symbol file in memory.
1292 info exceptions REGEXP
1293 Display the list of Ada exceptions defined in the program being
1294 debugged. If provided, only the exceptions whose names match REGEXP
1299 set debug symfile off|on
1301 Control display of debugging info regarding reading symbol files and
1302 symbol tables within those files
1304 set print raw frame-arguments
1305 show print raw frame-arguments
1306 Set/show whether to print frame arguments in raw mode,
1307 disregarding any defined pretty-printers.
1309 set remote trace-status-packet
1310 show remote trace-status-packet
1311 Set/show the use of remote protocol qTStatus packet.
1315 Control display of debugging messages related to Nios II targets.
1319 Control whether target-assisted range stepping is enabled.
1321 set startup-with-shell
1322 show startup-with-shell
1323 Specifies whether Unix child processes are started via a shell or
1328 Use the target memory cache for accesses to the code segment. This
1329 improves performance of remote debugging (particularly disassembly).
1331 * You can now use a literal value 'unlimited' for options that
1332 interpret 0 or -1 as meaning "unlimited". E.g., "set
1333 trace-buffer-size unlimited" is now an alias for "set
1334 trace-buffer-size -1" and "set height unlimited" is now an alias for
1337 * The "set debug symtab-create" debugging option of GDB has been changed to
1338 accept a verbosity level. 0 means "off", 1 provides basic debugging
1339 output, and values of 2 or greater provides more verbose output.
1341 * New command-line options
1343 Display the details of GDB configure-time options.
1345 * The command 'tsave' can now support new option '-ctf' to save trace
1346 buffer in Common Trace Format.
1348 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1351 * GDB now implements the the C++ 'typeid' operator.
1353 * The new convenience variable $_exception holds the exception being
1354 thrown or caught at an exception-related catchpoint.
1356 * The exception-related catchpoints, like "catch throw", now accept a
1357 regular expression which can be used to filter exceptions by type.
1359 * The new convenience variable $_exitsignal is automatically set to
1360 the terminating signal number when the program being debugged dies
1361 due to an uncaught signal.
1365 ** All MI commands now accept an optional "--language" option.
1366 Support for this feature can be verified by using the "-list-features"
1367 command, which should contain "language-option".
1369 ** The new command -info-gdb-mi-command allows the user to determine
1370 whether a GDB/MI command is supported or not.
1372 ** The "^error" result record returned when trying to execute an undefined
1373 GDB/MI command now provides a variable named "code" whose content is the
1374 "undefined-command" error code. Support for this feature can be verified
1375 by using the "-list-features" command, which should contain
1376 "undefined-command-error-code".
1378 ** The -trace-save MI command can optionally save trace buffer in Common
1381 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1383 ** The command -data-list-register-values now accepts an optional
1384 "--skip-unavailable" option. When used, only the available registers
1387 ** The new command -trace-frame-collected dumps collected variables,
1388 computed expressions, tvars, memory and registers in a traceframe.
1390 ** The commands -stack-list-locals, -stack-list-arguments and
1391 -stack-list-variables now accept an option "--skip-unavailable".
1392 When used, only the available locals or arguments are displayed.
1394 ** The -exec-run command now accepts an optional "--start" option.
1395 When used, the command follows the same semantics as the "start"
1396 command, stopping the program's execution at the start of its
1397 main subprogram. Support for this feature can be verified using
1398 the "-list-features" command, which should contain
1399 "exec-run-start-option".
1401 ** The new commands -catch-assert and -catch-exceptions insert
1402 catchpoints stopping the program when Ada exceptions are raised.
1404 ** The new command -info-ada-exceptions provides the equivalent of
1405 the new "info exceptions" command.
1407 * New system-wide configuration scripts
1408 A GDB installation now provides scripts suitable for use as system-wide
1409 configuration scripts for the following systems:
1413 * GDB now supports target-assigned range stepping with remote targets.
1414 This improves the performance of stepping source lines by reducing
1415 the number of control packets from/to GDB. See "New remote packets"
1418 * GDB now understands the element 'tvar' in the XML traceframe info.
1419 It has the id of the collected trace state variables.
1421 * On S/390 targets that provide the transactional-execution feature,
1422 the program interruption transaction diagnostic block (TDB) is now
1423 represented as a number of additional "registers" in GDB.
1425 * New remote packets
1429 The vCont packet supports a new 'r' action, that tells the remote
1430 stub to step through an address range itself, without GDB
1431 involvemement at each single-step.
1433 qXfer:libraries-svr4:read's annex
1434 The previously unused annex of the qXfer:libraries-svr4:read packet
1435 is now used to support passing an argument list. The remote stub
1436 reports support for this argument list to GDB's qSupported query.
1437 The defined arguments are "start" and "prev", used to reduce work
1438 necessary for library list updating, resulting in significant
1441 * New features in the GDB remote stub, GDBserver
1443 ** GDBserver now supports target-assisted range stepping. Currently
1444 enabled on x86/x86_64 GNU/Linux targets.
1446 ** GDBserver now adds element 'tvar' in the XML in the reply to
1447 'qXfer:traceframe-info:read'. It has the id of the collected
1448 trace state variables.
1450 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1453 * New 'z' formatter for printing and examining memory, this displays the
1454 value as hexadecimal zero padded on the left to the size of the type.
1456 * GDB can now use Windows x64 unwinding data.
1458 * The "set remotebaud" command has been replaced by "set serial baud".
1459 Similarly, "show remotebaud" has been replaced by "show serial baud".
1460 The "set remotebaud" and "show remotebaud" commands are still available
1461 to provide backward compatibility with older versions of GDB.
1463 *** Changes in GDB 7.6
1465 * Target record has been renamed to record-full.
1466 Record/replay is now enabled with the "record full" command.
1467 This also affects settings that are associated with full record/replay
1468 that have been moved from "set/show record" to "set/show record full":
1470 set|show record full insn-number-max
1471 set|show record full stop-at-limit
1472 set|show record full memory-query
1474 * A new record target "record-btrace" has been added. The new target
1475 uses hardware support to record the control-flow of a process. It
1476 does not support replaying the execution, but it implements the
1477 below new commands for investigating the recorded execution log.
1478 This new recording method can be enabled using:
1482 The "record-btrace" target is only available on Intel Atom processors
1483 and requires a Linux kernel 2.6.32 or later.
1485 * Two new commands have been added for record/replay to give information
1486 about the recorded execution without having to replay the execution.
1487 The commands are only supported by "record btrace".
1489 record instruction-history prints the execution history at
1490 instruction granularity
1492 record function-call-history prints the execution history at
1493 function granularity
1495 * New native configurations
1497 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1498 FreeBSD/powerpc powerpc*-*-freebsd
1499 x86_64/Cygwin x86_64-*-cygwin*
1500 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1504 ARM AArch64 aarch64*-*-elf
1505 ARM AArch64 GNU/Linux aarch64*-*-linux
1506 Lynx 178 PowerPC powerpc-*-lynx*178
1507 x86_64/Cygwin x86_64-*-cygwin*
1508 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1510 * If the configured location of system.gdbinit file (as given by the
1511 --with-system-gdbinit option at configure time) is in the
1512 data-directory (as specified by --with-gdb-datadir at configure
1513 time) or in one of its subdirectories, then GDB will look for the
1514 system-wide init file in the directory specified by the
1515 --data-directory command-line option.
1517 * New command line options:
1519 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1520 other initialization files, unlike -nx which disables all of them.
1522 * Removed command line options
1524 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1527 * The 'ptype' and 'whatis' commands now accept an argument to control
1530 * 'info proc' now works on some core files.
1534 ** Vectors can be created with gdb.Type.vector.
1536 ** Python's atexit.register now works in GDB.
1538 ** Types can be pretty-printed via a Python API.
1540 ** Python 3 is now supported (in addition to Python 2.4 or later)
1542 ** New class gdb.Architecture exposes GDB's internal representation
1543 of architecture in the Python API.
1545 ** New method Frame.architecture returns the gdb.Architecture object
1546 corresponding to the frame's architecture.
1548 * New Python-based convenience functions:
1550 ** $_memeq(buf1, buf2, length)
1551 ** $_streq(str1, str2)
1553 ** $_regex(str, regex)
1555 * The 'cd' command now defaults to using '~' (the home directory) if not
1558 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1559 default for GCC since November 2000.
1561 * The command 'forward-search' can now be abbreviated as 'fo'.
1563 * The command 'info tracepoints' can now display 'installed on target'
1564 or 'not installed on target' for each non-pending location of tracepoint.
1566 * New configure options
1568 --enable-libmcheck/--disable-libmcheck
1569 By default, development versions are built with -lmcheck on hosts
1570 that support it, in order to help track memory corruption issues.
1571 Release versions, on the other hand, are built without -lmcheck
1572 by default. The --enable-libmcheck/--disable-libmcheck configure
1573 options allow the user to override that default.
1574 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1575 This configure option allows the user to build GDB with
1576 libbabeltrace using which GDB can read Common Trace Format data.
1578 * New commands (for set/show, see "New options" below)
1581 Catch signals. This is similar to "handle", but allows commands and
1582 conditions to be attached.
1585 List the BFDs known to GDB.
1587 python-interactive [command]
1589 Start a Python interactive prompt, or evaluate the optional command
1590 and print the result of expressions.
1593 "py" is a new alias for "python".
1595 enable type-printer [name]...
1596 disable type-printer [name]...
1597 Enable or disable type printers.
1601 ** For the Renesas Super-H architecture, the "regs" command has been removed
1602 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1607 set print type methods (on|off)
1608 show print type methods
1609 Control whether method declarations are displayed by "ptype".
1610 The default is to show them.
1612 set print type typedefs (on|off)
1613 show print type typedefs
1614 Control whether typedef definitions are displayed by "ptype".
1615 The default is to show them.
1617 set filename-display basename|relative|absolute
1618 show filename-display
1619 Control the way in which filenames is displayed.
1620 The default is "relative", which preserves previous behavior.
1622 set trace-buffer-size
1623 show trace-buffer-size
1624 Request target to change the size of trace buffer.
1626 set remote trace-buffer-size-packet auto|on|off
1627 show remote trace-buffer-size-packet
1628 Control the use of the remote protocol `QTBuffer:size' packet.
1632 Control display of debugging messages related to ARM AArch64.
1635 set debug coff-pe-read
1636 show debug coff-pe-read
1637 Control display of debugging messages related to reading of COFF/PE
1642 Control display of debugging messages related to Mach-O symbols
1645 set debug notification
1646 show debug notification
1647 Control display of debugging info for async remote notification.
1651 ** Command parameter changes are now notified using new async record
1652 "=cmd-param-changed".
1653 ** Trace frame changes caused by command "tfind" are now notified using
1654 new async record "=traceframe-changed".
1655 ** The creation, deletion and modification of trace state variables
1656 are now notified using new async records "=tsv-created",
1657 "=tsv-deleted" and "=tsv-modified".
1658 ** The start and stop of process record are now notified using new
1659 async record "=record-started" and "=record-stopped".
1660 ** Memory changes are now notified using new async record
1662 ** The data-disassemble command response will include a "fullname" field
1663 containing the absolute file name when source has been requested.
1664 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1665 command, to allow pattern filling of memory areas.
1666 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1667 library load/unload events.
1668 ** The response to breakpoint commands and breakpoint async records
1669 includes an "installed" field containing a boolean state about each
1670 non-pending tracepoint location is whether installed on target or not.
1671 ** Output of the "-trace-status" command includes a "trace-file" field
1672 containing the name of the trace file being examined. This field is
1673 optional, and only present when examining a trace file.
1674 ** The "fullname" field is now always present along with the "file" field,
1675 even if the file cannot be found by GDB.
1677 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1678 You must have the LZMA library available when configuring GDB for this
1679 feature to be enabled. For more information, see:
1680 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1682 * New remote packets
1685 Set the size of trace buffer. The remote stub reports support for this
1686 packet to gdb's qSupported query.
1689 Enable Branch Trace Store (BTS)-based branch tracing for the current
1690 thread. The remote stub reports support for this packet to gdb's
1694 Disable branch tracing for the current thread. The remote stub reports
1695 support for this packet to gdb's qSupported query.
1698 Read the traced branches for the current thread. The remote stub
1699 reports support for this packet to gdb's qSupported query.
1701 *** Changes in GDB 7.5
1703 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1704 for more x32 ABI info.
1706 * GDB now supports access to MIPS DSP registers on Linux targets.
1708 * GDB now supports debugging microMIPS binaries.
1710 * The "info os" command on GNU/Linux can now display information on
1711 several new classes of objects managed by the operating system:
1712 "info os procgroups" lists process groups
1713 "info os files" lists file descriptors
1714 "info os sockets" lists internet-domain sockets
1715 "info os shm" lists shared-memory regions
1716 "info os semaphores" lists semaphores
1717 "info os msg" lists message queues
1718 "info os modules" lists loaded kernel modules
1720 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1721 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1722 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1723 options and inspect the probe arguments using the new $_probe_arg family
1724 of convenience variables. You can obtain more information about SystemTap
1725 in <http://sourceware.org/systemtap/>.
1727 * GDB now supports reversible debugging on ARM, it allows you to
1728 debug basic ARM and THUMB instructions, and provides
1729 record/replay support.
1731 * The option "symbol-reloading" has been deleted as it is no longer used.
1735 ** GDB commands implemented in Python can now be put in command class
1738 ** The "maint set python print-stack on|off" is now deleted.
1740 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1741 apply "flag enum"-style pretty-printing to any enum.
1743 ** gdb.lookup_symbol can now work when there is no current frame.
1745 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1746 the source at which the symbol was defined.
1748 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1749 method 'value'. The former indicates whether the symbol needs a
1750 frame in order to compute its value, and the latter computes the
1753 ** A new method 'referenced_value' on gdb.Value objects which can
1754 dereference pointer as well as C++ reference values.
1756 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1757 which return the global and static blocks (as gdb.Block objects),
1758 of the underlying symbol table, respectively.
1760 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1761 object associated with a PC value.
1763 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1764 of the address range occupied by code for the current source line.
1766 * Go language support.
1767 GDB now supports debugging programs written in the Go programming
1770 * GDBserver now supports stdio connections.
1771 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1773 * The binary "gdbtui" can no longer be built or installed.
1774 Use "gdb -tui" instead.
1776 * GDB will now print "flag" enums specially. A flag enum is one where
1777 all the enumerator values have no bits in common when pairwise
1778 "and"ed. When printing a value whose type is a flag enum, GDB will
1779 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1780 (gdb) print (enum E) 3
1783 * The filename part of a linespec will now match trailing components
1784 of a source file name. For example, "break gcc/expr.c:1000" will
1785 now set a breakpoint in build/gcc/expr.c, but not
1786 build/libcpp/expr.c.
1788 * The "info proc" and "generate-core-file" commands will now also
1789 work on remote targets connected to GDBserver on Linux.
1791 * The command "info catch" has been removed. It has been disabled
1792 since December 2007.
1794 * The "catch exception" and "catch assert" commands now accept
1795 a condition at the end of the command, much like the "break"
1796 command does. For instance:
1798 (gdb) catch exception Constraint_Error if Barrier = True
1800 Previously, it was possible to add a condition to such catchpoints,
1801 but it had to be done as a second step, after the catchpoint had been
1802 created, using the "condition" command.
1804 * The "info static-tracepoint-marker" command will now also work on
1805 native Linux targets with in-process agent.
1807 * GDB can now set breakpoints on inlined functions.
1809 * The .gdb_index section has been updated to include symbols for
1810 inlined functions. GDB will ignore older .gdb_index sections by
1811 default, which could cause symbol files to be loaded more slowly
1812 until their .gdb_index sections can be recreated. The new command
1813 "set use-deprecated-index-sections on" will cause GDB to use any older
1814 .gdb_index sections it finds. This will restore performance, but the
1815 ability to set breakpoints on inlined functions will be lost in symbol
1816 files with older .gdb_index sections.
1818 The .gdb_index section has also been updated to record more information
1819 about each symbol. This speeds up the "info variables", "info functions"
1820 and "info types" commands when used with programs having the .gdb_index
1821 section, as well as speeding up debugging with shared libraries using
1822 the .gdb_index section.
1824 * Ada support for GDB/MI Variable Objects has been added.
1826 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1831 ** New command -info-os is the MI equivalent of "info os".
1833 ** Output logs ("set logging" and related) now include MI output.
1837 ** "set use-deprecated-index-sections on|off"
1838 "show use-deprecated-index-sections on|off"
1839 Controls the use of deprecated .gdb_index sections.
1841 ** "catch load" and "catch unload" can be used to stop when a shared
1842 library is loaded or unloaded, respectively.
1844 ** "enable count" can be used to auto-disable a breakpoint after
1847 ** "info vtbl" can be used to show the virtual method tables for
1848 C++ and Java objects.
1850 ** "explore" and its sub commands "explore value" and "explore type"
1851 can be used to recursively explore values and types of
1852 expressions. These commands are available only if GDB is
1853 configured with '--with-python'.
1855 ** "info auto-load" shows status of all kinds of auto-loaded files,
1856 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1857 sequences of commands files, "info auto-load python-scripts"
1858 shows status of auto-loading Python script files,
1859 "info auto-load local-gdbinit" shows status of loading init file
1860 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1861 status of inferior specific thread debugging shared library loading.
1863 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1864 and "show auto-load-scripts" commands have been deprecated, use their
1865 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1866 and "show auto-load python-scripts" counterparts instead.
1868 ** "dprintf location,format,args..." creates a dynamic printf, which
1869 is basically a breakpoint that does a printf and immediately
1870 resumes your program's execution, so it is like a printf that you
1871 can insert dynamically at runtime instead of at compiletime.
1873 ** "set print symbol"
1875 Controls whether GDB attempts to display the symbol, if any,
1876 corresponding to addresses it prints. This defaults to "on", but
1877 you can set it to "off" to restore GDB's previous behavior.
1879 * Deprecated commands
1881 ** For the Renesas Super-H architecture, the "regs" command has been
1882 deprecated, and "info all-registers" should be used instead.
1886 Renesas RL78 rl78-*-elf
1887 HP OpenVMS ia64 ia64-hp-openvms*
1889 * GDBserver supports evaluation of breakpoint conditions. When
1890 support is advertised by GDBserver, GDB may be told to send the
1891 breakpoint conditions in bytecode form to GDBserver. GDBserver
1892 will only report the breakpoint trigger to GDB when its condition
1897 set mips compression
1898 show mips compression
1899 Select the compressed ISA encoding used in functions that have no symbol
1900 information available. The encoding can be set to either of:
1903 and is updated automatically from ELF file flags if available.
1905 set breakpoint condition-evaluation
1906 show breakpoint condition-evaluation
1907 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1908 GDBserver ("target"). Default option "auto" chooses the most efficient
1910 This option can improve debugger efficiency depending on the speed of the
1914 Disable auto-loading globally.
1917 Show auto-loading setting of all kinds of auto-loaded files.
1919 set auto-load gdb-scripts on|off
1920 show auto-load gdb-scripts
1921 Control auto-loading of GDB canned sequences of commands files.
1923 set auto-load python-scripts on|off
1924 show auto-load python-scripts
1925 Control auto-loading of Python script files.
1927 set auto-load local-gdbinit on|off
1928 show auto-load local-gdbinit
1929 Control loading of init file (.gdbinit) from current directory.
1931 set auto-load libthread-db on|off
1932 show auto-load libthread-db
1933 Control auto-loading of inferior specific thread debugging shared library.
1935 set auto-load scripts-directory <dir1>[:<dir2>...]
1936 show auto-load scripts-directory
1937 Set a list of directories from which to load auto-loaded scripts.
1938 Automatically loaded Python scripts and GDB scripts are located in one
1939 of the directories listed by this option.
1940 The delimiter (':' above) may differ according to the host platform.
1942 set auto-load safe-path <dir1>[:<dir2>...]
1943 show auto-load safe-path
1944 Set a list of directories from which it is safe to auto-load files.
1945 The delimiter (':' above) may differ according to the host platform.
1947 set debug auto-load on|off
1948 show debug auto-load
1949 Control display of debugging info for auto-loading the files above.
1951 set dprintf-style gdb|call|agent
1953 Control the way in which a dynamic printf is performed; "gdb"
1954 requests a GDB printf command, while "call" causes dprintf to call a
1955 function in the inferior. "agent" requests that the target agent
1956 (such as GDBserver) do the printing.
1958 set dprintf-function <expr>
1959 show dprintf-function
1960 set dprintf-channel <expr>
1961 show dprintf-channel
1962 Set the function and optional first argument to the call when using
1963 the "call" style of dynamic printf.
1965 set disconnected-dprintf on|off
1966 show disconnected-dprintf
1967 Control whether agent-style dynamic printfs continue to be in effect
1968 after GDB disconnects.
1970 * New configure options
1972 --with-auto-load-dir
1973 Configure default value for the 'set auto-load scripts-directory'
1974 setting above. It defaults to '$debugdir:$datadir/auto-load',
1975 $debugdir representing global debugging info directories (available
1976 via 'show debug-file-directory') and $datadir representing GDB's data
1977 directory (available via 'show data-directory').
1979 --with-auto-load-safe-path
1980 Configure default value for the 'set auto-load safe-path' setting
1981 above. It defaults to the --with-auto-load-dir setting.
1983 --without-auto-load-safe-path
1984 Set 'set auto-load safe-path' to '/', effectively disabling this
1987 * New remote packets
1989 z0/z1 conditional breakpoints extension
1991 The z0/z1 breakpoint insertion packets have been extended to carry
1992 a list of conditional expressions over to the remote stub depending on the
1993 condition evaluation mode. The use of this extension can be controlled
1994 via the "set remote conditional-breakpoints-packet" command.
1998 Specify the signals which the remote stub may pass to the debugged
1999 program without GDB involvement.
2001 * New command line options
2003 --init-command=FILE, -ix Like --command, -x but execute it
2004 before loading inferior.
2005 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
2006 execute it before loading inferior.
2008 *** Changes in GDB 7.4
2010 * GDB now handles ambiguous linespecs more consistently; the existing
2011 FILE:LINE support has been expanded to other types of linespecs. A
2012 breakpoint will now be set on all matching locations in all
2013 inferiors, and locations will be added or removed according to
2016 * GDB now allows you to skip uninteresting functions and files when
2017 stepping with the "skip function" and "skip file" commands.
2019 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
2020 and "show remote hardware-watchpoint-length-limit". These allows to
2021 set or show the maximum length limit (in bytes) of a remote
2022 target hardware watchpoint.
2024 This allows e.g. to use "unlimited" hardware watchpoints with the
2025 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
2026 watchpoints are slower than real hardware watchpoints but are
2027 significantly faster than gdb software watchpoints.
2031 ** The register_pretty_printer function in module gdb.printing now takes
2032 an optional `replace' argument. If True, the new printer replaces any
2035 ** The "maint set python print-stack on|off" command has been
2036 deprecated and will be deleted in GDB 7.5.
2037 A new command: "set python print-stack none|full|message" has
2038 replaced it. Additionally, the default for "print-stack" is
2039 now "message", which just prints the error message without
2042 ** A prompt substitution hook (prompt_hook) is now available to the
2045 ** A new Python module, gdb.prompt has been added to the GDB Python
2046 modules library. This module provides functionality for
2047 escape sequences in prompts (used by set/show
2048 extended-prompt). These escape sequences are replaced by their
2049 corresponding value.
2051 ** Python commands and convenience-functions located in
2052 'data-directory'/python/gdb/command and
2053 'data-directory'/python/gdb/function are now automatically loaded
2056 ** Blocks now provide four new attributes. global_block and
2057 static_block will return the global and static blocks
2058 respectively. is_static and is_global are boolean attributes
2059 that indicate if the block is one of those two types.
2061 ** Symbols now provide the "type" attribute, the type of the symbol.
2063 ** The "gdb.breakpoint" function has been deprecated in favor of
2066 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2067 of a function. This class is based on the "finish" command
2068 available in the CLI.
2070 ** Type objects for struct and union types now allow access to
2071 the fields using standard Python dictionary (mapping) methods.
2072 For example, "some_type['myfield']" now works, as does
2073 "some_type.items()".
2075 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2078 ** A new function, "deep_items" has been added to the gdb.types
2079 module in the GDB Python modules library. This function returns
2080 an iterator over the fields of a struct or union type. Unlike
2081 the standard Python "iteritems" method, it will recursively traverse
2082 any anonymous fields.
2086 ** "*stopped" events can report several new "reason"s, such as
2089 ** Breakpoint changes are now notified using new async records, like
2090 "=breakpoint-modified".
2092 ** New command -ada-task-info.
2094 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2095 $sdir specifies the default system locations of shared libraries.
2096 $pdir specifies the directory where the libpthread used by the application
2099 GDB no longer looks in $sdir and $pdir after it has searched the directories
2100 mentioned in libthread-db-search-path. If you want to search those
2101 directories, they must be specified in libthread-db-search-path.
2102 The default value of libthread-db-search-path on GNU/Linux and Solaris
2103 systems is now "$sdir:$pdir".
2105 $pdir is not supported by gdbserver, it is currently ignored.
2106 $sdir is supported by gdbserver.
2108 * New configure option --with-iconv-bin.
2109 When using the internationalization support like the one in the GNU C
2110 library, GDB will invoke the "iconv" program to get a list of supported
2111 character sets. If this program lives in a non-standard location, one can
2112 use this option to specify where to find it.
2114 * When natively debugging programs on PowerPC BookE processors running
2115 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2116 watchpoints, which specify a mask in addition to an address to watch.
2117 The mask specifies that some bits of an address (the bits which are
2118 reset in the mask) should be ignored when matching the address accessed
2119 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2120 section in the user manual for more details.
2122 * The new option --once causes GDBserver to stop listening for connections once
2123 the first connection is made. The listening port used by GDBserver will
2124 become available after that.
2126 * New commands "info macros" and "alias" have been added.
2128 * New function parameters suffix @entry specifies value of function parameter
2129 at the time the function got called. Entry values are available only since
2135 "!" is now an alias of the "shell" command.
2136 Note that no space is needed between "!" and SHELL COMMAND.
2140 watch EXPRESSION mask MASK_VALUE
2141 The watch command now supports the mask argument which allows creation
2142 of masked watchpoints, if the current architecture supports this feature.
2144 info auto-load-scripts [REGEXP]
2145 This command was formerly named "maintenance print section-scripts".
2146 It is now generally useful and is no longer a maintenance-only command.
2148 info macro [-all] [--] MACRO
2149 The info macro command has new options `-all' and `--'. The first for
2150 printing all definitions of a macro. The second for explicitly specifying
2151 the end of arguments and the beginning of the macro name in case the macro
2152 name starts with a hyphen.
2154 collect[/s] EXPRESSIONS
2155 The tracepoint collect command now takes an optional modifier "/s"
2156 that directs it to dereference pointer-to-character types and
2157 collect the bytes of memory up to a zero byte. The behavior is
2158 similar to what you see when you use the regular print command on a
2159 string. An optional integer following the "/s" sets a bound on the
2160 number of bytes that will be collected.
2163 The trace start command now interprets any supplied arguments as a
2164 note to be recorded with the trace run, with an effect similar to
2165 setting the variable trace-notes.
2168 The trace stop command now interprets any arguments as a note to be
2169 mentioned along with the tstatus report that the trace was stopped
2170 with a command. The effect is similar to setting the variable
2173 * Tracepoints can now be enabled and disabled at any time after a trace
2174 experiment has been started using the standard "enable" and "disable"
2175 commands. It is now possible to start a trace experiment with no enabled
2176 tracepoints; GDB will display a warning, but will allow the experiment to
2177 begin, assuming that tracepoints will be enabled as needed while the trace
2180 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2181 locations with 4-byte instructions, when they were previously
2182 limited to locations with instructions of 5 bytes or longer.
2186 set debug dwarf2-read
2187 show debug dwarf2-read
2188 Turns on or off display of debugging messages related to reading
2189 DWARF debug info. The default is off.
2191 set debug symtab-create
2192 show debug symtab-create
2193 Turns on or off display of debugging messages related to symbol table
2194 creation. The default is off.
2197 show extended-prompt
2198 Set the GDB prompt, and allow escape sequences to be inserted to
2199 display miscellaneous information (see 'help set extended-prompt'
2200 for the list of sequences). This prompt (and any information
2201 accessed through the escape sequences) is updated every time the
2202 prompt is displayed.
2204 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2205 show print entry-values
2206 Set printing of frame argument values at function entry. In some cases
2207 GDB can determine the value of function argument which was passed by the
2208 function caller, even if the value was modified inside the called function.
2210 set debug entry-values
2211 show debug entry-values
2212 Control display of debugging info for determining frame argument values at
2213 function entry and virtual tail call frames.
2215 set basenames-may-differ
2216 show basenames-may-differ
2217 Set whether a source file may have multiple base names.
2218 (A "base name" is the name of a file with the directory part removed.
2219 Example: The base name of "/home/user/hello.c" is "hello.c".)
2220 If set, GDB will canonicalize file names (e.g., expand symlinks)
2221 before comparing them. Canonicalization is an expensive operation,
2222 but it allows the same file be known by more than one base name.
2223 If not set (the default), all source files are assumed to have just
2224 one base name, and gdb will do file name comparisons more efficiently.
2230 Set a user name and notes for the current and any future trace runs.
2231 This is useful for long-running and/or disconnected traces, to
2232 inform others (or yourself) as to who is running the trace, supply
2233 contact information, or otherwise explain what is going on.
2235 set trace-stop-notes
2236 show trace-stop-notes
2237 Set a note attached to the trace run, that is displayed when the
2238 trace has been stopped by a tstop command. This is useful for
2239 instance as an explanation, if you are stopping a trace run that was
2240 started by someone else.
2242 * New remote packets
2246 Dynamically enable a tracepoint in a started trace experiment.
2250 Dynamically disable a tracepoint in a started trace experiment.
2254 Set the user and notes of the trace run.
2258 Query the current status of a tracepoint.
2262 Query the minimum length of instruction at which a fast tracepoint may
2265 * Dcache size (number of lines) and line-size are now runtime-configurable
2266 via "set dcache line" and "set dcache line-size" commands.
2270 Texas Instruments TMS320C6x tic6x-*-*
2274 Renesas RL78 rl78-*-elf
2276 *** Changes in GDB 7.3.1
2278 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2280 *** Changes in GDB 7.3
2282 * GDB has a new command: "thread find [REGEXP]".
2283 It finds the thread id whose name, target id, or thread extra info
2284 matches the given regular expression.
2286 * The "catch syscall" command now works on mips*-linux* targets.
2288 * The -data-disassemble MI command now supports modes 2 and 3 for
2289 dumping the instruction opcodes.
2291 * New command line options
2293 -data-directory DIR Specify DIR as the "data-directory".
2294 This is mostly for testing purposes.
2296 * The "maint set python auto-load on|off" command has been renamed to
2297 "set auto-load-scripts on|off".
2299 * GDB has a new command: "set directories".
2300 It is like the "dir" command except that it replaces the
2301 source path list instead of augmenting it.
2303 * GDB now understands thread names.
2305 On GNU/Linux, "info threads" will display the thread name as set by
2306 prctl or pthread_setname_np.
2308 There is also a new command, "thread name", which can be used to
2309 assign a name internally for GDB to display.
2312 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2313 has been integrated into GDB.
2317 ** The function gdb.Write now accepts an optional keyword 'stream'.
2318 This keyword, when provided, will direct the output to either
2319 stdout, stderr, or GDB's logging output.
2321 ** Parameters can now be be sub-classed in Python, and in particular
2322 you may implement the get_set_doc and get_show_doc functions.
2323 This improves how Parameter set/show documentation is processed
2324 and allows for more dynamic content.
2326 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2327 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2328 have an is_valid method.
2330 ** Breakpoints can now be sub-classed in Python, and in particular
2331 you may implement a 'stop' function that is executed each time
2332 the inferior reaches that breakpoint.
2334 ** New function gdb.lookup_global_symbol looks up a global symbol.
2336 ** GDB values in Python are now callable if the value represents a
2337 function. For example, if 'some_value' represents a function that
2338 takes two integer parameters and returns a value, you can call
2339 that function like so:
2341 result = some_value (10,20)
2343 ** Module gdb.types has been added.
2344 It contains a collection of utilities for working with gdb.Types objects:
2345 get_basic_type, has_field, make_enum_dict.
2347 ** Module gdb.printing has been added.
2348 It contains utilities for writing and registering pretty-printers.
2349 New classes: PrettyPrinter, SubPrettyPrinter,
2350 RegexpCollectionPrettyPrinter.
2351 New function: register_pretty_printer.
2353 ** New commands "info pretty-printers", "enable pretty-printer" and
2354 "disable pretty-printer" have been added.
2356 ** gdb.parameter("directories") is now available.
2358 ** New function gdb.newest_frame returns the newest frame in the
2361 ** The gdb.InferiorThread class has a new "name" attribute. This
2362 holds the thread's name.
2364 ** Python Support for Inferior events.
2365 Python scripts can add observers to be notified of events
2366 occurring in the process being debugged.
2367 The following events are currently supported:
2368 - gdb.events.cont Continue event.
2369 - gdb.events.exited Inferior exited event.
2370 - gdb.events.stop Signal received, and Breakpoint hit events.
2374 ** GDB now puts template parameters in scope when debugging in an
2375 instantiation. For example, if you have:
2377 template<int X> int func (void) { return X; }
2379 then if you step into func<5>, "print X" will show "5". This
2380 feature requires proper debuginfo support from the compiler; it
2381 was added to GCC 4.5.
2383 ** The motion commands "next", "finish", "until", and "advance" now
2384 work better when exceptions are thrown. In particular, GDB will
2385 no longer lose control of the inferior; instead, the GDB will
2386 stop the inferior at the point at which the exception is caught.
2387 This functionality requires a change in the exception handling
2388 code that was introduced in GCC 4.5.
2390 * GDB now follows GCC's rules on accessing volatile objects when
2391 reading or writing target state during expression evaluation.
2392 One notable difference to prior behavior is that "print x = 0"
2393 no longer generates a read of x; the value of the assignment is
2394 now always taken directly from the value being assigned.
2396 * GDB now has some support for using labels in the program's source in
2397 linespecs. For instance, you can use "advance label" to continue
2398 execution to a label.
2400 * GDB now has support for reading and writing a new .gdb_index
2401 section. This section holds a fast index of DWARF debugging
2402 information and can be used to greatly speed up GDB startup and
2403 operation. See the documentation for `save gdb-index' for details.
2405 * The "watch" command now accepts an optional "-location" argument.
2406 When used, this causes GDB to watch the memory referred to by the
2407 expression. Such a watchpoint is never deleted due to it going out
2410 * GDB now supports thread debugging of core dumps on GNU/Linux.
2412 GDB now activates thread debugging using the libthread_db library
2413 when debugging GNU/Linux core dumps, similarly to when debugging
2414 live processes. As a result, when debugging a core dump file, GDB
2415 is now able to display pthread_t ids of threads. For example, "info
2416 threads" shows the same output as when debugging the process when it
2417 was live. In earlier releases, you'd see something like this:
2420 * 1 LWP 6780 main () at main.c:10
2422 While now you see this:
2425 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2427 It is also now possible to inspect TLS variables when debugging core
2430 When debugging a core dump generated on a machine other than the one
2431 used to run GDB, you may need to point GDB at the correct
2432 libthread_db library with the "set libthread-db-search-path"
2433 command. See the user manual for more details on this command.
2435 * When natively debugging programs on PowerPC BookE processors running
2436 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2437 which stop execution of the inferior whenever it executes an instruction
2438 at any address within the specified range. See the "PowerPC Embedded"
2439 section in the user manual for more details.
2441 * New features in the GDB remote stub, GDBserver
2443 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2444 and i686 LynxOS (version 5.x).
2446 ** GDBserver is now supported on Blackfin Linux.
2448 * New native configurations
2450 ia64 HP-UX ia64-*-hpux*
2454 Analog Devices, Inc. Blackfin Processor bfin-*
2456 * Ada task switching is now supported on sparc-elf targets when
2457 debugging a program using the Ravenscar Profile. For more information,
2458 see the "Tasking Support when using the Ravenscar Profile" section
2459 in the GDB user manual.
2461 * Guile support was removed.
2463 * New features in the GNU simulator
2465 ** The --map-info flag lists all known core mappings.
2467 ** CFI flashes may be simulated via the "cfi" device.
2469 *** Changes in GDB 7.2
2471 * Shared library support for remote targets by default
2473 When GDB is configured for a generic, non-OS specific target, like
2474 for example, --target=arm-eabi or one of the many *-*-elf targets,
2475 GDB now queries remote stubs for loaded shared libraries using the
2476 `qXfer:libraries:read' packet. Previously, shared library support
2477 was always disabled for such configurations.
2481 ** Argument Dependent Lookup (ADL)
2483 In C++ ADL lookup directs function search to the namespaces of its
2484 arguments even if the namespace has not been imported.
2494 Here the compiler will search for `foo' in the namespace of 'b'
2495 and find A::foo. GDB now supports this. This construct is commonly
2496 used in the Standard Template Library for operators.
2498 ** Improved User Defined Operator Support
2500 In addition to member operators, GDB now supports lookup of operators
2501 defined in a namespace and imported with a `using' directive, operators
2502 defined in the global scope, operators imported implicitly from an
2503 anonymous namespace, and the ADL operators mentioned in the previous
2505 GDB now also supports proper overload resolution for all the previously
2506 mentioned flavors of operators.
2508 ** static const class members
2510 Printing of static const class members that are initialized in the
2511 class definition has been fixed.
2513 * Windows Thread Information Block access.
2515 On Windows targets, GDB now supports displaying the Windows Thread
2516 Information Block (TIB) structure. This structure is visible either
2517 by using the new command `info w32 thread-information-block' or, by
2518 dereferencing the new convenience variable named `$_tlb', a
2519 thread-specific pointer to the TIB. This feature is also supported
2520 when remote debugging using GDBserver.
2522 * Static tracepoints
2524 Static tracepoints are calls in the user program into a tracing
2525 library. One such library is a port of the LTTng kernel tracer to
2526 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2527 When debugging with GDBserver, GDB now supports combining the GDB
2528 tracepoint machinery with such libraries. For example: the user can
2529 use GDB to probe a static tracepoint marker (a call from the user
2530 program into the tracing library) with the new "strace" command (see
2531 "New commands" below). This creates a "static tracepoint" in the
2532 breakpoint list, that can be manipulated with the same feature set
2533 as fast and regular tracepoints. E.g., collect registers, local and
2534 global variables, collect trace state variables, and define
2535 tracepoint conditions. In addition, the user can collect extra
2536 static tracepoint marker specific data, by collecting the new
2537 $_sdata internal variable. When analyzing the trace buffer, you can
2538 inspect $_sdata like any other variable available to GDB. For more
2539 information, see the "Tracepoints" chapter in GDB user manual. New
2540 remote packets have been defined to support static tracepoints, see
2541 the "New remote packets" section below.
2543 * Better reconstruction of tracepoints after disconnected tracing
2545 GDB will attempt to download the original source form of tracepoint
2546 definitions when starting a trace run, and then will upload these
2547 upon reconnection to the target, resulting in a more accurate
2548 reconstruction of the tracepoints that are in use on the target.
2552 You can now exercise direct control over the ways that GDB can
2553 affect your program. For instance, you can disallow the setting of
2554 breakpoints, so that the program can run continuously (assuming
2555 non-stop mode). In addition, the "observer" variable is available
2556 to switch all of the different controls; in observer mode, GDB
2557 cannot affect the target's behavior at all, which is useful for
2558 tasks like diagnosing live systems in the field.
2560 * The new convenience variable $_thread holds the number of the
2563 * New remote packets
2567 Return the address of the Windows Thread Information Block of a given thread.
2571 In response to several of the tracepoint packets, the target may now
2572 also respond with a number of intermediate `qRelocInsn' request
2573 packets before the final result packet, to have GDB handle
2574 relocating an instruction to execute at a different address. This
2575 is particularly useful for stubs that support fast tracepoints. GDB
2576 reports support for this feature in the qSupported packet.
2580 List static tracepoint markers in the target program.
2584 List static tracepoint markers at a given address in the target
2587 qXfer:statictrace:read
2589 Read the static trace data collected (by a `collect $_sdata'
2590 tracepoint action). The remote stub reports support for this packet
2591 to gdb's qSupported query.
2595 Send the current settings of GDB's permission flags.
2599 Send part of the source (textual) form of a tracepoint definition,
2600 which includes location, conditional, and action list.
2602 * The source command now accepts a -s option to force searching for the
2603 script in the source search path even if the script name specifies
2606 * New features in the GDB remote stub, GDBserver
2608 - GDBserver now support tracepoints (including fast tracepoints, and
2609 static tracepoints). The feature is currently supported by the
2610 i386-linux and amd64-linux builds. See the "Tracepoints support
2611 in gdbserver" section in the manual for more information.
2613 GDBserver JIT compiles the tracepoint's conditional agent
2614 expression bytecode into native code whenever possible for low
2615 overhead dynamic tracepoints conditionals. For such tracepoints,
2616 an expression that examines program state is evaluated when the
2617 tracepoint is reached, in order to determine whether to capture
2618 trace data. If the condition is simple and false, processing the
2619 tracepoint finishes very quickly and no data is gathered.
2621 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2622 for static tracepoints support.
2624 - GDBserver now supports x86_64 Windows 64-bit debugging.
2626 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2627 it understands register description.
2629 * The --batch flag now disables pagination and queries.
2631 * X86 general purpose registers
2633 GDB now supports reading/writing byte, word and double-word x86
2634 general purpose registers directly. This means you can use, say,
2635 $ah or $ax to refer, respectively, to the byte register AH and
2636 16-bit word register AX that are actually portions of the 32-bit
2637 register EAX or 64-bit register RAX.
2639 * The `commands' command now accepts a range of breakpoints to modify.
2640 A plain `commands' following a command that creates multiple
2641 breakpoints affects all the breakpoints set by that command. This
2642 applies to breakpoints set by `rbreak', and also applies when a
2643 single `break' command creates multiple breakpoints (e.g.,
2644 breakpoints on overloaded c++ functions).
2646 * The `rbreak' command now accepts a filename specification as part of
2647 its argument, limiting the functions selected by the regex to those
2648 in the specified file.
2650 * Support for remote debugging Windows and SymbianOS shared libraries
2651 from Unix hosts has been improved. Non Windows GDB builds now can
2652 understand target reported file names that follow MS-DOS based file
2653 system semantics, such as file names that include drive letters and
2654 use the backslash character as directory separator. This makes it
2655 possible to transparently use the "set sysroot" and "set
2656 solib-search-path" on Unix hosts to point as host copies of the
2657 target's shared libraries. See the new command "set
2658 target-file-system-kind" described below, and the "Commands to
2659 specify files" section in the user manual for more information.
2663 eval template, expressions...
2664 Convert the values of one or more expressions under the control
2665 of the string template to a command line, and call it.
2667 set target-file-system-kind unix|dos-based|auto
2668 show target-file-system-kind
2669 Set or show the assumed file system kind for target reported file
2672 save breakpoints <filename>
2673 Save all current breakpoint definitions to a file suitable for use
2674 in a later debugging session. To read the saved breakpoint
2675 definitions, use the `source' command.
2677 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2680 info static-tracepoint-markers
2681 Display information about static tracepoint markers in the target.
2683 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2684 Define a static tracepoint by probing a marker at the given
2685 function, line, address, or marker ID.
2689 Enable and disable observer mode.
2691 set may-write-registers on|off
2692 set may-write-memory on|off
2693 set may-insert-breakpoints on|off
2694 set may-insert-tracepoints on|off
2695 set may-insert-fast-tracepoints on|off
2696 set may-interrupt on|off
2697 Set individual permissions for GDB effects on the target. Note that
2698 some of these settings can have undesirable or surprising
2699 consequences, particularly when changed in the middle of a session.
2700 For instance, disabling the writing of memory can prevent
2701 breakpoints from being inserted, cause single-stepping to fail, or
2702 even crash your program, if you disable after breakpoints have been
2703 inserted. However, GDB should not crash.
2705 set record memory-query on|off
2706 show record memory-query
2707 Control whether to stop the inferior if memory changes caused
2708 by an instruction cannot be recorded.
2713 The disassemble command now supports "start,+length" form of two arguments.
2717 ** GDB now provides a new directory location, called the python directory,
2718 where Python scripts written for GDB can be installed. The location
2719 of that directory is <data-directory>/python, where <data-directory>
2720 is the GDB data directory. For more details, see section `Scripting
2721 GDB using Python' in the manual.
2723 ** The GDB Python API now has access to breakpoints, symbols, symbol
2724 tables, program spaces, inferiors, threads and frame's code blocks.
2725 Additionally, GDB Parameters can now be created from the API, and
2726 manipulated via set/show in the CLI.
2728 ** New functions gdb.target_charset, gdb.target_wide_charset,
2729 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2731 ** New exception gdb.GdbError.
2733 ** Pretty-printers are now also looked up in the current program space.
2735 ** Pretty-printers can now be individually enabled and disabled.
2737 ** GDB now looks for names of Python scripts to auto-load in a
2738 special section named `.debug_gdb_scripts', in addition to looking
2739 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2741 * Tracepoint actions were unified with breakpoint commands. In particular,
2742 there are no longer differences in "info break" output for breakpoints and
2743 tracepoints and the "commands" command can be used for both tracepoints and
2744 regular breakpoints.
2748 ARM Symbian arm*-*-symbianelf*
2750 * D language support.
2751 GDB now supports debugging programs written in the D programming
2754 * GDB now supports the extended ptrace interface for PowerPC which is
2755 available since Linux kernel version 2.6.34. This automatically enables
2756 any hardware breakpoints and additional hardware watchpoints available in
2757 the processor. The old ptrace interface exposes just one hardware
2758 watchpoint and no hardware breakpoints.
2760 * GDB is now able to use the Data Value Compare (DVC) register available on
2761 embedded PowerPC processors to implement in hardware simple watchpoint
2762 conditions of the form:
2764 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2766 This works in native GDB running on Linux kernels with the extended ptrace
2767 interface mentioned above.
2769 *** Changes in GDB 7.1
2773 ** Namespace Support
2775 GDB now supports importing of namespaces in C++. This enables the
2776 user to inspect variables from imported namespaces. Support for
2777 namepace aliasing has also been added. So, if a namespace is
2778 aliased in the current scope (e.g. namepace C=A; ) the user can
2779 print variables using the alias (e.g. (gdb) print C::x).
2783 All known bugs relating to the printing of virtual base class were
2784 fixed. It is now possible to call overloaded static methods using a
2789 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2790 and reinterpret_cast<> are now handled by the C++ expression parser.
2794 Xilinx MicroBlaze microblaze-*-*
2799 Xilinx MicroBlaze microblaze
2802 * Multi-program debugging.
2804 GDB now has support for multi-program (a.k.a. multi-executable or
2805 multi-exec) debugging. This allows for debugging multiple inferiors
2806 simultaneously each running a different program under the same GDB
2807 session. See "Debugging Multiple Inferiors and Programs" in the
2808 manual for more information. This implied some user visible changes
2809 in the multi-inferior support. For example, "info inferiors" now
2810 lists inferiors that are not running yet or that have exited
2811 already. See also "New commands" and "New options" below.
2813 * New tracing features
2815 GDB's tracepoint facility now includes several new features:
2817 ** Trace state variables
2819 GDB tracepoints now include support for trace state variables, which
2820 are variables managed by the target agent during a tracing
2821 experiment. They are useful for tracepoints that trigger each
2822 other, so for instance one tracepoint can count hits in a variable,
2823 and then a second tracepoint has a condition that is true when the
2824 count reaches a particular value. Trace state variables share the
2825 $-syntax of GDB convenience variables, and can appear in both
2826 tracepoint actions and condition expressions. Use the "tvariable"
2827 command to create, and "info tvariables" to view; see "Trace State
2828 Variables" in the manual for more detail.
2832 GDB now includes an option for defining fast tracepoints, which
2833 targets may implement more efficiently, such as by installing a jump
2834 into the target agent rather than a trap instruction. The resulting
2835 speedup can be by two orders of magnitude or more, although the
2836 tradeoff is that some program locations on some target architectures
2837 might not allow fast tracepoint installation, for instance if the
2838 instruction to be replaced is shorter than the jump. To request a
2839 fast tracepoint, use the "ftrace" command, with syntax identical to
2840 the regular trace command.
2842 ** Disconnected tracing
2844 It is now possible to detach GDB from the target while it is running
2845 a trace experiment, then reconnect later to see how the experiment
2846 is going. In addition, a new variable disconnected-tracing lets you
2847 tell the target agent whether to continue running a trace if the
2848 connection is lost unexpectedly.
2852 GDB now has the ability to save the trace buffer into a file, and
2853 then use that file as a target, similarly to you can do with
2854 corefiles. You can select trace frames, print data that was
2855 collected in them, and use tstatus to display the state of the
2856 tracing run at the moment that it was saved. To create a trace
2857 file, use "tsave <filename>", and to use it, do "target tfile
2860 ** Circular trace buffer
2862 You can ask the target agent to handle the trace buffer as a
2863 circular buffer, discarding the oldest trace frames to make room for
2864 newer ones, by setting circular-trace-buffer to on. This feature may
2865 not be available for all target agents.
2870 The disassemble command, when invoked with two arguments, now requires
2871 the arguments to be comma-separated.
2874 The info variables command now displays variable definitions. Files
2875 which only declare a variable are not shown.
2878 The source command is now capable of sourcing Python scripts.
2879 This feature is dependent on the debugger being build with Python
2882 Related to this enhancement is also the introduction of a new command
2883 "set script-extension" (see below).
2885 * New commands (for set/show, see "New options" below)
2887 record save [<FILENAME>]
2888 Save a file (in core file format) containing the process record
2889 execution log for replay debugging at a later time.
2891 record restore <FILENAME>
2892 Restore the process record execution log that was saved at an
2893 earlier time, for replay debugging.
2895 add-inferior [-copies <N>] [-exec <FILENAME>]
2898 clone-inferior [-copies <N>] [ID]
2899 Make a new inferior ready to execute the same program another
2900 inferior has loaded.
2905 maint info program-spaces
2906 List the program spaces loaded into GDB.
2908 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2909 show remote interrupt-sequence
2910 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2911 as the sequence to the remote target in order to interrupt the execution.
2912 Ctrl-C is a default. Some system prefers BREAK which is high level of
2913 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2914 Magic SysRq g. It is BREAK signal and character 'g'.
2916 set remote interrupt-on-connect [on | off]
2917 show remote interrupt-on-connect
2918 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2919 remote target when gdb connects to it. This is needed when you debug
2922 set remotebreak [on | off]
2924 Deprecated. Use "set/show remote interrupt-sequence" instead.
2926 tvariable $NAME [ = EXP ]
2927 Create or modify a trace state variable.
2930 List trace state variables and their values.
2932 delete tvariable $NAME ...
2933 Delete one or more trace state variables.
2936 Evaluate the given expressions without collecting anything into the
2937 trace buffer. (Valid in tracepoint actions only.)
2939 ftrace FN / FILE:LINE / *ADDR
2940 Define a fast tracepoint at the given function, line, or address.
2942 * New expression syntax
2944 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2945 GDB now parses 0b101010 identically with 42.
2949 set follow-exec-mode new|same
2950 show follow-exec-mode
2951 Control whether GDB reuses the same inferior across an exec call or
2952 creates a new one. This is useful to be able to restart the old
2953 executable after the inferior having done an exec call.
2955 set default-collect EXPR, ...
2956 show default-collect
2957 Define a list of expressions to be collected at each tracepoint.
2958 This is a useful way to ensure essential items are not overlooked,
2959 such as registers or a critical global variable.
2961 set disconnected-tracing
2962 show disconnected-tracing
2963 If set to 1, the target is instructed to continue tracing if it
2964 loses its connection to GDB. If 0, the target is to stop tracing
2967 set circular-trace-buffer
2968 show circular-trace-buffer
2969 If set to on, the target is instructed to use a circular trace buffer
2970 and discard the oldest trace frames instead of stopping the trace due
2971 to a full trace buffer. If set to off, the trace stops when the buffer
2972 fills up. Some targets may not support this.
2974 set script-extension off|soft|strict
2975 show script-extension
2976 If set to "off", the debugger does not perform any script language
2977 recognition, and all sourced files are assumed to be GDB scripts.
2978 If set to "soft" (the default), files are sourced according to
2979 filename extension, falling back to GDB scripts if the first
2981 If set to "strict", files are sourced according to filename extension.
2983 set ada trust-PAD-over-XVS on|off
2984 show ada trust-PAD-over-XVS
2985 If off, activate a workaround against a bug in the debugging information
2986 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2987 the GCC sources for more information about the GNAT encoding and
2988 PAD types in particular). It is always safe to set this option to
2989 off, but this introduces a slight performance penalty. The default
2992 * Python API Improvements
2994 ** GDB provides the new class gdb.LazyString. This is useful in
2995 some pretty-printing cases. The new method gdb.Value.lazy_string
2996 provides a simple way to create objects of this type.
2998 ** The fields returned by gdb.Type.fields now have an
2999 `is_base_class' attribute.
3001 ** The new method gdb.Type.range returns the range of an array type.
3003 ** The new method gdb.parse_and_eval can be used to parse and
3004 evaluate an expression.
3006 * New remote packets
3009 Define a trace state variable.
3012 Get the current value of a trace state variable.
3015 Set desired tracing behavior upon disconnection.
3018 Set the trace buffer to be linear or circular.
3021 Get data about the tracepoints currently in use.
3025 Process record now works correctly with hardware watchpoints.
3027 Multiple bug fixes have been made to the mips-irix port, making it
3028 much more reliable. In particular:
3029 - Debugging threaded applications is now possible again. Previously,
3030 GDB would hang while starting the program, or while waiting for
3031 the program to stop at a breakpoint.
3032 - Attaching to a running process no longer hangs.
3033 - An error occurring while loading a core file has been fixed.
3034 - Changing the value of the PC register now works again. This fixes
3035 problems observed when using the "jump" command, or when calling
3036 a function from GDB, or even when assigning a new value to $pc.
3037 - With the "finish" and "return" commands, the return value for functions
3038 returning a small array is now correctly printed.
3039 - It is now possible to break on shared library code which gets executed
3040 during a shared library init phase (code executed while executing
3041 their .init section). Previously, the breakpoint would have no effect.
3042 - GDB is now able to backtrace through the signal handler for
3043 non-threaded programs.
3045 PIE (Position Independent Executable) programs debugging is now supported.
3046 This includes debugging execution of PIC (Position Independent Code) shared
3047 libraries although for that, it should be possible to run such libraries as an
3050 *** Changes in GDB 7.0
3052 * GDB now has an interface for JIT compilation. Applications that
3053 dynamically generate code can create symbol files in memory and register
3054 them with GDB. For users, the feature should work transparently, and
3055 for JIT developers, the interface is documented in the GDB manual in the
3056 "JIT Compilation Interface" chapter.
3058 * Tracepoints may now be conditional. The syntax is as for
3059 breakpoints; either an "if" clause appended to the "trace" command,
3060 or the "condition" command is available. GDB sends the condition to
3061 the target for evaluation using the same bytecode format as is used
3062 for tracepoint actions.
3064 * The disassemble command now supports: an optional /r modifier, print the
3065 raw instructions in hex as well as in symbolic form, and an optional /m
3066 modifier to print mixed source+assembly.
3068 * Process record and replay
3070 In a architecture environment that supports ``process record and
3071 replay'', ``process record and replay'' target can record a log of
3072 the process execution, and replay it with both forward and reverse
3075 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3076 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3077 set execution-direction {forward|reverse}, for targets that support
3080 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3081 feature is available with a native GDB running on kernel version
3084 * GDB now has support for multi-byte and wide character sets on the
3085 target. Strings whose character type is wchar_t, char16_t, or
3086 char32_t are now correctly printed. GDB supports wide- and unicode-
3087 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3088 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3089 `printf'. This feature requires iconv to work properly; if your
3090 system does not have a working iconv, GDB can use GNU libiconv. See
3091 the installation instructions for more information.
3093 * GDB now supports automatic retrieval of shared library files from
3094 remote targets. To use this feature, specify a system root that begins
3095 with the `remote:' prefix, either via the `set sysroot' command or via
3096 the `--with-sysroot' configure-time option.
3098 * "info sharedlibrary" now takes an optional regex of libraries to show,
3099 and it now reports if a shared library has no debugging information.
3101 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3102 now complete on file names.
3104 * When completing in expressions, gdb will attempt to limit
3105 completions to allowable structure or union fields, where appropriate.
3106 For instance, consider:
3108 # struct example { int f1; double f2; };
3109 # struct example variable;
3112 If the user types TAB at the end of this command line, the available
3113 completions will be "f1" and "f2".
3115 * Inlined functions are now supported. They show up in backtraces, and
3116 the "step", "next", and "finish" commands handle them automatically.
3118 * GDB now supports the token-splicing (##) and stringification (#)
3119 operators when expanding macros. It also supports variable-arity
3122 * GDB now supports inspecting extra signal information, exported by
3123 the new $_siginfo convenience variable. The feature is currently
3124 implemented on linux ARM, i386 and amd64.
3126 * GDB can now display the VFP floating point registers and NEON vector
3127 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3128 can provide these registers (requires Linux 2.6.30 or later). Remote
3129 and simulator targets may also provide them.
3131 * New remote packets
3134 Search memory for a sequence of bytes.
3137 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3138 operation over reliable transport links. Use of this packet is
3139 controlled by the `set remote noack-packet' command.
3142 Kill the process with the specified process ID. Use this in preference
3143 to `k' when multiprocess protocol extensions are supported.
3146 Obtains additional operating system information
3150 Read or write additional signal information.
3152 * Removed remote protocol undocumented extension
3154 An undocumented extension to the remote protocol's `S' stop reply
3155 packet that permited the stub to pass a process id was removed.
3156 Remote servers should use the `T' stop reply packet instead.
3158 * GDB now supports multiple function calling conventions according to the
3159 DWARF-2 DW_AT_calling_convention function attribute.
3161 * The SH target utilizes the aforementioned change to distinguish between gcc
3162 and Renesas calling convention. It also adds the new CLI commands
3163 `set/show sh calling-convention'.
3165 * GDB can now read compressed debug sections, as produced by GNU gold
3166 with the --compress-debug-sections=zlib flag.
3168 * 64-bit core files are now supported on AIX.
3170 * Thread switching is now supported on Tru64.
3172 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3173 which will be allocated using malloc later in program execution.
3175 * The qXfer:libraries:read remote procotol packet now allows passing a
3176 list of section offsets.
3178 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3179 conditions handling signals delivered during attach or thread creation
3180 have also been fixed.
3182 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3183 From the user's standpoint, all unqualified instances of True and False
3184 are treated as the standard definitions, regardless of context.
3186 * GDB now parses C++ symbol and type names more flexibly. For
3189 template<typename T> class C { };
3192 GDB will now correctly handle all of:
3194 ptype C<char const *>
3195 ptype C<char const*>
3196 ptype C<const char *>
3197 ptype C<const char*>
3199 * New features in the GDB remote stub, gdbserver
3201 - The "--wrapper" command-line argument tells gdbserver to use a
3202 wrapper program to launch programs for debugging.
3204 - On PowerPC and S/390 targets, it is now possible to use a single
3205 gdbserver executable to debug both 32-bit and 64-bit programs.
3206 (This requires gdbserver itself to be built as a 64-bit executable.)
3208 - gdbserver uses the new noack protocol mode for TCP connections to
3209 reduce communications latency, if also supported and enabled in GDB.
3211 - Support for the sparc64-linux-gnu target is now included in
3214 - The amd64-linux build of gdbserver now supports debugging both
3215 32-bit and 64-bit programs.
3217 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3218 now support hardware watchpoints, and will use them automatically
3223 GDB now has support for scripting using Python. Whether this is
3224 available is determined at configure time.
3226 New GDB commands can now be written in Python.
3228 * Ada tasking support
3230 Ada tasks can now be inspected in GDB. The following commands have
3234 Print the list of Ada tasks.
3236 Print detailed information about task number N.
3238 Print the task number of the current task.
3240 Switch the context of debugging to task number N.
3242 * Support for user-defined prefixed commands. The "define" command can
3243 add new commands to existing prefixes, e.g. "target".
3245 * Multi-inferior, multi-process debugging.
3247 GDB now has generalized support for multi-inferior debugging. See
3248 "Debugging Multiple Inferiors" in the manual for more information.
3249 Although availability still depends on target support, the command
3250 set is more uniform now. The GNU/Linux specific multi-forks support
3251 has been migrated to this new framework. This implied some user
3252 visible changes; see "New commands" and also "Removed commands"
3255 * Target descriptions can now describe the target OS ABI. See the
3256 "Target Description Format" section in the user manual for more
3259 * Target descriptions can now describe "compatible" architectures
3260 to indicate that the target can execute applications for a different
3261 architecture in addition to those for the main target architecture.
3262 See the "Target Description Format" section in the user manual for
3265 * Multi-architecture debugging.
3267 GDB now includes general supports for debugging applications on
3268 hybrid systems that use more than one single processor architecture
3269 at the same time. Each such hybrid architecture still requires
3270 specific support to be added. The only hybrid architecture supported
3271 in this version of GDB is the Cell Broadband Engine.
3273 * GDB now supports integrated debugging of Cell/B.E. applications that
3274 use both the PPU and SPU architectures. To enable support for hybrid
3275 Cell/B.E. debugging, you need to configure GDB to support both the
3276 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3277 --enable-targets configure option.
3279 * Non-stop mode debugging.
3281 For some targets, GDB now supports an optional mode of operation in
3282 which you can examine stopped threads while other threads continue
3283 to execute freely. This is referred to as non-stop mode, with the
3284 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3285 section in the user manual for more information.
3287 To be able to support remote non-stop debugging, a remote stub needs
3288 to implement the non-stop mode remote protocol extensions, as
3289 described in the "Remote Non-Stop" section of the user manual. The
3290 GDB remote stub, gdbserver, has been adjusted to support these
3291 extensions on linux targets.
3293 * New commands (for set/show, see "New options" below)
3295 catch syscall [NAME(S) | NUMBER(S)]
3296 Catch system calls. Arguments, which should be names of system
3297 calls or their numbers, mean catch only those syscalls. Without
3298 arguments, every syscall will be caught. When the inferior issues
3299 any of the specified syscalls, GDB will stop and announce the system
3300 call, both when it is called and when its call returns. This
3301 feature is currently available with a native GDB running on the
3302 Linux Kernel, under the following architectures: x86, x86_64,
3303 PowerPC and PowerPC64.
3305 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3307 Search memory for a sequence of bytes.
3309 maint set python print-stack
3310 maint show python print-stack
3311 Show a stack trace when an error is encountered in a Python script.
3314 Invoke CODE by passing it to the Python interpreter.
3319 These allow macros to be defined, undefined, and listed
3323 Show operating system information about processes.
3326 List the inferiors currently under GDB's control.
3329 Switch focus to inferior number NUM.
3332 Detach from inferior number NUM.
3335 Kill inferior number NUM.
3339 set spu stop-on-load
3340 show spu stop-on-load
3341 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3343 set spu auto-flush-cache
3344 show spu auto-flush-cache
3345 Control whether to automatically flush the software-managed cache
3346 during Cell/B.E. debugging.
3348 set sh calling-convention
3349 show sh calling-convention
3350 Control the calling convention used when calling SH target functions.
3353 show debug timestamp
3354 Control display of timestamps with GDB debugging output.
3356 set disassemble-next-line
3357 show disassemble-next-line
3358 Control display of disassembled source lines or instructions when
3361 set remote noack-packet
3362 show remote noack-packet
3363 Set/show the use of remote protocol QStartNoAckMode packet. See above
3364 under "New remote packets."
3366 set remote query-attached-packet
3367 show remote query-attached-packet
3368 Control use of remote protocol `qAttached' (query-attached) packet.
3370 set remote read-siginfo-object
3371 show remote read-siginfo-object
3372 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3375 set remote write-siginfo-object
3376 show remote write-siginfo-object
3377 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3380 set remote reverse-continue
3381 show remote reverse-continue
3382 Control use of remote protocol 'bc' (reverse-continue) packet.
3384 set remote reverse-step
3385 show remote reverse-step
3386 Control use of remote protocol 'bs' (reverse-step) packet.
3388 set displaced-stepping
3389 show displaced-stepping
3390 Control displaced stepping mode. Displaced stepping is a way to
3391 single-step over breakpoints without removing them from the debuggee.
3392 Also known as "out-of-line single-stepping".
3395 show debug displaced
3396 Control display of debugging info for displaced stepping.
3398 maint set internal-error
3399 maint show internal-error
3400 Control what GDB does when an internal error is detected.
3402 maint set internal-warning
3403 maint show internal-warning
3404 Control what GDB does when an internal warning is detected.
3409 Use a wrapper program to launch programs for debugging.
3411 set multiple-symbols (all|ask|cancel)
3412 show multiple-symbols
3413 The value of this variable can be changed to adjust the debugger behavior
3414 when an expression or a breakpoint location contains an ambiguous symbol
3415 name (an overloaded function name, for instance).
3417 set breakpoint always-inserted
3418 show breakpoint always-inserted
3419 Keep breakpoints always inserted in the target, as opposed to inserting
3420 them when resuming the target, and removing them when the target stops.
3421 This option can improve debugger performance on slow remote targets.
3423 set arm fallback-mode (arm|thumb|auto)
3424 show arm fallback-mode
3425 set arm force-mode (arm|thumb|auto)
3427 These commands control how ARM GDB determines whether instructions
3428 are ARM or Thumb. The default for both settings is auto, which uses
3429 the current CPSR value for instructions without symbols; previous
3430 versions of GDB behaved as if "set arm fallback-mode arm".
3432 set disable-randomization
3433 show disable-randomization
3434 Standalone programs run with the virtual address space randomization enabled
3435 by default on some platforms. This option keeps the addresses stable across
3436 multiple debugging sessions.
3440 Control whether other threads are stopped or not when some thread hits
3445 Requests that asynchronous execution is enabled in the target, if available.
3446 In this case, it's possible to resume target in the background, and interact
3447 with GDB while the target is running. "show target-async" displays the
3448 current state of asynchronous execution of the target.
3450 set target-wide-charset
3451 show target-wide-charset
3452 The target-wide-charset is the name of the character set that GDB
3453 uses when printing characters whose type is wchar_t.
3455 set tcp auto-retry (on|off)
3457 set tcp connect-timeout
3458 show tcp connect-timeout
3459 These commands allow GDB to retry failed TCP connections to a remote stub
3460 with a specified timeout period; this is useful if the stub is launched
3461 in parallel with GDB but may not be ready to accept connections immediately.
3463 set libthread-db-search-path
3464 show libthread-db-search-path
3465 Control list of directories which GDB will search for appropriate
3468 set schedule-multiple (on|off)
3469 show schedule-multiple
3470 Allow GDB to resume all threads of all processes or only threads of
3471 the current process.
3475 Use more aggressive caching for accesses to the stack. This improves
3476 performance of remote debugging (particularly backtraces) without
3477 affecting correctness.
3479 set interactive-mode (on|off|auto)
3480 show interactive-mode
3481 Control whether GDB runs in interactive mode (on) or not (off).
3482 When in interactive mode, GDB waits for the user to answer all
3483 queries. Otherwise, GDB does not wait and assumes the default
3484 answer. When set to auto (the default), GDB determines which
3485 mode to use based on the stdin settings.
3490 For program forks, this is replaced by the new more generic `info
3491 inferiors' command. To list checkpoints, you can still use the
3492 `info checkpoints' command, which was an alias for the `info forks'
3496 Replaced by the new `inferior' command. To switch between
3497 checkpoints, you can still use the `restart' command, which was an
3498 alias for the `fork' command.
3501 This is removed, since some targets don't have a notion of
3502 processes. To switch between processes, you can still use the
3503 `inferior' command using GDB's own inferior number.
3506 For program forks, this is replaced by the new more generic `kill
3507 inferior' command. To delete a checkpoint, you can still use the
3508 `delete checkpoint' command, which was an alias for the `delete
3512 For program forks, this is replaced by the new more generic `detach
3513 inferior' command. To detach a checkpoint, you can still use the
3514 `detach checkpoint' command, which was an alias for the `detach
3517 * New native configurations
3519 x86/x86_64 Darwin i[34567]86-*-darwin*
3521 x86_64 MinGW x86_64-*-mingw*
3525 Lattice Mico32 lm32-*
3526 x86 DICOS i[34567]86-*-dicos*
3527 x86_64 DICOS x86_64-*-dicos*
3530 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3531 (mingw32ce) debugging.
3537 These commands were actually not implemented on any target.
3539 *** Changes in GDB 6.8
3541 * New native configurations
3543 NetBSD/hppa hppa*-*netbsd*
3544 Xtensa GNU/Linux xtensa*-*-linux*
3548 NetBSD/hppa hppa*-*-netbsd*
3549 Xtensa GNU/Lunux xtensa*-*-linux*
3551 * Change in command line behavior -- corefiles vs. process ids.
3553 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3554 attaching to process NUMBER fails, GDB no longer attempts to open a
3555 core file named NUMBER. Attaching to a program using the -c option
3556 is no longer supported. Instead, use the '-p' or '--pid' options.
3558 * GDB can now be built as a native debugger for debugging Windows x86
3559 (mingw32) Portable Executable (PE) programs.
3561 * Pending breakpoints no longer change their number when their address
3564 * GDB now supports breakpoints with multiple locations,
3565 including breakpoints on C++ constructors, inside C++ templates,
3566 and in inlined functions.
3568 * GDB's ability to debug optimized code has been improved. GDB more
3569 accurately identifies function bodies and lexical blocks that occupy
3570 more than one contiguous range of addresses.
3572 * Target descriptions can now describe registers for PowerPC.
3574 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3575 registers on PowerPC targets.
3577 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3578 targets even when the libthread_db library is not available.
3580 * The GDB remote stub, gdbserver, now supports the new file transfer
3581 commands (remote put, remote get, and remote delete).
3583 * The GDB remote stub, gdbserver, now supports run and attach in
3584 extended-remote mode.
3586 * hppa*64*-*-hpux11* target broken
3587 The debugger is unable to start a program and fails with the following
3588 error: "Error trying to get information about dynamic linker".
3589 The gdb-6.7 release is also affected.
3591 * GDB now supports the --enable-targets= configure option to allow
3592 building a single GDB executable that supports multiple remote
3593 target architectures.
3595 * GDB now supports debugging C and C++ programs which use the
3596 Decimal Floating Point extension. In addition, the PowerPC target
3597 now has a set of pseudo-registers to inspect decimal float values
3598 stored in two consecutive float registers.
3600 * The -break-insert MI command can optionally create pending
3603 * Improved support for debugging Ada
3604 Many improvements to the Ada language support have been made. These
3606 - Better support for Ada2005 interface types
3607 - Improved handling of arrays and slices in general
3608 - Better support for Taft-amendment types
3609 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3611 - Improved command completion in Ada
3614 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3619 set print frame-arguments (all|scalars|none)
3620 show print frame-arguments
3621 The value of this variable can be changed to control which argument
3622 values should be printed by the debugger when displaying a frame.
3627 Transfer files to and from a remote target, and delete remote files.
3634 Transfer files to and from a remote target, and delete remote files.
3636 * New remote packets
3643 Open, close, read, write, and delete files on the remote system.
3646 Attach to an existing process on the remote system, in extended-remote
3650 Run a new process on the remote system, in extended-remote mode.
3652 *** Changes in GDB 6.7
3654 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3655 bfd, libiberty and opcodes, as revealed by static analysis donated by
3656 Coverity, Inc. (http://scan.coverity.com).
3658 * When looking up multiply-defined global symbols, GDB will now prefer the
3659 symbol definition in the current shared library if it was built using the
3660 -Bsymbolic linker option.
3662 * When the Text User Interface (TUI) is not configured, GDB will now
3663 recognize the -tui command-line option and print a message that the TUI
3666 * The GDB remote stub, gdbserver, now has lower overhead for high
3667 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3669 * GDB for MIPS targets now autodetects whether a remote target provides
3670 32-bit or 64-bit register values.
3672 * Support for C++ member pointers has been improved.
3674 * GDB now understands XML target descriptions, which specify the
3675 target's overall architecture. GDB can read a description from
3676 a local file or over the remote serial protocol.
3678 * Vectors of single-byte data use a new integer type which is not
3679 automatically displayed as character or string data.
3681 * The /s format now works with the print command. It displays
3682 arrays of single-byte integers and pointers to single-byte integers
3685 * Target descriptions can now describe target-specific registers,
3686 for architectures which have implemented the support (currently
3687 only ARM, M68K, and MIPS).
3689 * GDB and the GDB remote stub, gdbserver, now support the XScale
3692 * The GDB remote stub, gdbserver, has been updated to support
3693 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3694 has been rewritten to use the standard GDB remote protocol.
3696 * GDB can now step into C++ functions which are called through thunks.
3698 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3700 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3701 layout. It also supports a TextSeg= and DataSeg= response when only
3702 segment base addresses (rather than offsets) are available.
3704 * The /i format now outputs any trailing branch delay slot instructions
3705 immediately following the last instruction within the count specified.
3707 * The GDB remote protocol "T" stop reply packet now supports a
3708 "library" response. Combined with the new "qXfer:libraries:read"
3709 packet, this response allows GDB to debug shared libraries on targets
3710 where the operating system manages the list of loaded libraries (e.g.
3711 Windows and SymbianOS).
3713 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3714 (DLLs) on Windows and Windows CE targets.
3716 * GDB now supports a faster verification that a .debug file matches its binary
3717 according to its build-id signature, if the signature is present.
3723 Enable or disable hardware flow control (RTS/CTS) on the serial port
3724 when debugging using remote targets.
3726 set mem inaccessible-by-default
3727 show mem inaccessible-by-default
3728 If the target supplies a memory map, for instance via the remote
3729 protocol's "qXfer:memory-map:read" packet, setting this variable
3730 prevents GDB from accessing memory outside the memory map. This
3731 is useful for targets with memory mapped registers or which react
3732 badly to accesses of unmapped address space.
3734 set breakpoint auto-hw
3735 show breakpoint auto-hw
3736 If the target supplies a memory map, for instance via the remote
3737 protocol's "qXfer:memory-map:read" packet, setting this variable
3738 lets GDB use hardware breakpoints automatically for memory regions
3739 where it can not use software breakpoints. This covers both the
3740 "break" command and internal breakpoints used for other commands
3741 including "next" and "finish".
3744 catch exception unhandled
3745 Stop the program execution when Ada exceptions are raised.
3748 Stop the program execution when an Ada assertion failed.
3752 Set an alternate system root for target files. This is a more
3753 general version of "set solib-absolute-prefix", which is now
3754 an alias to "set sysroot".
3757 Provide extended SPU facility status information. This set of
3758 commands is available only when debugging the Cell/B.E. SPU
3761 * New native configurations
3763 OpenBSD/sh sh*-*openbsd*
3766 unset tdesc filename
3768 Use the specified local file as an XML target description, and do
3769 not query the target for its built-in description.
3773 OpenBSD/sh sh*-*-openbsd*
3774 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3775 Toshiba Media Processor mep-elf
3777 * New remote packets
3780 Ignore the specified signals; pass them directly to the debugged program
3781 without stopping other threads or reporting them to GDB.
3783 qXfer:features:read:
3784 Read an XML target description from the target, which describes its
3789 Read or write contents of an spufs file on the target system. These
3790 packets are available only on the Cell/B.E. SPU architecture.
3792 qXfer:libraries:read:
3793 Report the loaded shared libraries. Combined with new "T" packet
3794 response, this packet allows GDB to debug shared libraries on
3795 targets where the operating system manages the list of loaded
3796 libraries (e.g. Windows and SymbianOS).
3800 Support for these obsolete configurations has been removed.
3808 i[34567]86-*-lynxos*
3809 i[34567]86-*-netware*
3810 i[34567]86-*-sco3.2v5*
3811 i[34567]86-*-sco3.2v4*
3813 i[34567]86-*-sysv4.2*
3816 i[34567]86-*-unixware2*
3817 i[34567]86-*-unixware*
3826 * Other removed features
3833 Various m68k-only ROM monitors.
3840 Various Renesas ROM monitors and debugging interfaces for SH and
3845 Support for a Macraigor serial interface to on-chip debugging.
3846 GDB does not directly support the newer parallel or USB
3851 A debug information format. The predecessor to DWARF 2 and
3852 DWARF 3, which are still supported.
3854 Support for the HP aCC compiler on HP-UX/PA-RISC
3856 SOM-encapsulated symbolic debugging information, automatic
3857 invocation of pxdb, and the aCC custom C++ ABI. This does not
3858 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3859 with aCC can still be debugged on an assembly level.
3861 MIPS ".pdr" sections
3863 A MIPS-specific format used to describe stack frame layout
3864 in debugging information.
3868 GDB could work with an older version of Guile to debug
3869 the interpreter and Scheme programs running in it.
3871 set mips stack-arg-size
3872 set mips saved-gpreg-size
3874 Use "set mips abi" to control parameter passing for MIPS.
3876 *** Changes in GDB 6.6
3881 Cell Broadband Engine SPU spu-elf
3883 * GDB can now be configured as a cross-debugger targeting native Windows
3884 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3885 running on a Windows system over TCP/IP to debug Windows programs.
3887 * The GDB remote stub, gdbserver, has been updated to support Windows and
3888 Cygwin debugging. Both single-threaded and multi-threaded programs are
3891 * The "set trust-readonly-sections" command works again. This command was
3892 broken in GDB 6.3, 6.4, and 6.5.
3894 * The "load" command now supports writing to flash memory, if the remote
3895 stub provides the required support.
3897 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3898 longer requires symbolic debug information (e.g. DWARF-2).
3903 unset substitute-path
3904 show substitute-path
3905 Manage a list of substitution rules that GDB uses to rewrite the name
3906 of the directories where the sources are located. This can be useful
3907 for instance when the sources were moved to a different location
3908 between compilation and debugging.
3912 Print each CLI command as it is executed. Each command is prefixed with
3913 a number of `+' symbols representing the nesting depth.
3914 The source command now has a `-v' option to enable the same feature.
3918 The ARM Demon monitor support (RDP protocol, "target rdp").
3920 Kernel Object Display, an embedded debugging feature which only worked with
3921 an obsolete version of Cisco IOS.
3923 The 'set download-write-size' and 'show download-write-size' commands.
3925 * New remote packets
3928 Tell a stub about GDB client features, and request remote target features.
3929 The first feature implemented is PacketSize, which allows the target to
3930 specify the size of packets it can handle - to minimize the number of
3931 packets required and improve performance when connected to a remote
3935 Fetch an OS auxilliary vector from the remote stub. This packet is a
3936 more efficient replacement for qPart:auxv:read.
3938 qXfer:memory-map:read:
3939 Fetch a memory map from the remote stub, including information about
3940 RAM, ROM, and flash memory devices.
3945 Erase and program a flash memory device.
3947 * Removed remote packets
3950 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3951 used it, and only gdbserver implemented it.
3953 *** Changes in GDB 6.5
3957 Renesas M32C/M16C m32c-elf
3959 Morpho Technologies ms1 ms1-elf
3963 init-if-undefined Initialize a convenience variable, but
3964 only if it doesn't already have a value.
3966 The following commands are presently only implemented for native GNU/Linux:
3968 checkpoint Save a snapshot of the program state.
3970 restart <n> Return the program state to a
3971 previously saved state.
3973 info checkpoints List currently saved checkpoints.
3975 delete-checkpoint <n> Delete a previously saved checkpoint.
3977 set|show detach-on-fork Tell gdb whether to detach from a newly
3978 forked process, or to keep debugging it.
3980 info forks List forks of the user program that
3981 are available to be debugged.
3983 fork <n> Switch to debugging one of several
3984 forks of the user program that are
3985 available to be debugged.
3987 delete-fork <n> Delete a fork from the list of forks
3988 that are available to be debugged (and
3989 kill the forked process).
3991 detach-fork <n> Delete a fork from the list of forks
3992 that are available to be debugged (and
3993 allow the process to continue).
3997 Morpho Technologies ms2 ms1-elf
3999 * Improved Windows host support
4001 GDB now builds as a cross debugger hosted on i686-mingw32, including
4002 native console support, and remote communications using either
4003 network sockets or serial ports.
4005 * Improved Modula-2 language support
4007 GDB can now print most types in the Modula-2 syntax. This includes:
4008 basic types, set types, record types, enumerated types, range types,
4009 pointer types and ARRAY types. Procedure var parameters are correctly
4010 printed and hexadecimal addresses and character constants are also
4011 written in the Modula-2 syntax. Best results can be obtained by using
4012 GNU Modula-2 together with the -gdwarf-2 command line option.
4016 The ARM rdi-share module.
4018 The Netware NLM debug server.
4020 *** Changes in GDB 6.4
4022 * New native configurations
4024 OpenBSD/arm arm*-*-openbsd*
4025 OpenBSD/mips64 mips64-*-openbsd*
4029 Morpho Technologies ms1 ms1-elf
4031 * New command line options
4033 --batch-silent As for --batch, but totally silent.
4034 --return-child-result The debugger will exist with the same value
4035 the child (debugged) program exited with.
4036 --eval-command COMMAND, -ex COMMAND
4037 Execute a single GDB CLI command. This may be
4038 specified multiple times and in conjunction
4039 with the --command (-x) option.
4041 * Deprecated commands removed
4043 The following commands, that were deprecated in 2000, have been
4047 set|show arm disassembly-flavor set|show arm disassembler
4048 othernames set arm disassembler
4049 set|show remotedebug set|show debug remote
4050 set|show archdebug set|show debug arch
4051 set|show eventdebug set|show debug event
4054 * New BSD user-level threads support
4056 It is now possible to debug programs using the user-level threads
4057 library on OpenBSD and FreeBSD. Currently supported (target)
4060 FreeBSD/amd64 x86_64-*-freebsd*
4061 FreeBSD/i386 i386-*-freebsd*
4062 OpenBSD/i386 i386-*-openbsd*
4064 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4065 are not yet supported.
4067 * New support for Matsushita MN10300 w/sim added
4068 (Work in progress). mn10300-elf.
4070 * REMOVED configurations and files
4072 VxWorks and the XDR protocol *-*-vxworks
4073 Motorola MCORE mcore-*-*
4074 National Semiconductor NS32000 ns32k-*-*
4076 * New "set print array-indexes" command
4078 After turning this setting "on", GDB prints the index of each element
4079 when displaying arrays. The default is "off" to preserve the previous
4082 * VAX floating point support
4084 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4086 * User-defined command support
4088 In addition to using $arg0..$arg9 for argument passing, it is now possible
4089 to use $argc to determine now many arguments have been passed. See the
4090 section on user-defined commands in the user manual for more information.
4092 *** Changes in GDB 6.3:
4094 * New command line option
4096 GDB now accepts -l followed by a number to set the timeout for remote
4099 * GDB works with GCC -feliminate-dwarf2-dups
4101 GDB now supports a more compact representation of DWARF-2 debug
4102 information using DW_FORM_ref_addr references. These are produced
4103 by GCC with the option -feliminate-dwarf2-dups and also by some
4104 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4105 to use -feliminate-dwarf2-dups.
4107 * Internationalization
4109 When supported by the host system, GDB will be built with
4110 internationalization (libintl). The task of marking up the sources is
4111 continued, we're looking forward to our first translation.
4115 Initial support for debugging programs compiled with the GNAT
4116 implementation of the Ada programming language has been integrated
4117 into GDB. In this release, support is limited to expression evaluation.
4119 * New native configurations
4121 GNU/Linux/m32r m32r-*-linux-gnu
4125 GDB's remote protocol now includes support for the 'p' packet. This
4126 packet is used to fetch individual registers from a remote inferior.
4128 * END-OF-LIFE registers[] compatibility module
4130 GDB's internal register infrastructure has been completely rewritten.
4131 The new infrastructure making possible the implementation of key new
4132 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4135 GDB 6.3 will be the last release to include the the registers[]
4136 compatibility module that allowed out-of-date configurations to
4137 continue to work. This change directly impacts the following
4147 powerpc bdm protocol
4149 Unless there is activity to revive these configurations, they will be
4150 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4152 * OBSOLETE configurations and files
4154 Configurations that have been declared obsolete in this release have
4155 been commented out. Unless there is activity to revive these
4156 configurations, the next release of GDB will have their sources
4157 permanently REMOVED.
4166 *** Changes in GDB 6.2.1:
4168 * MIPS `break main; run' gave an heuristic-fence-post warning
4170 When attempting to run even a simple program, a warning about
4171 heuristic-fence-post being hit would be reported. This problem has
4174 * MIPS IRIX 'long double' crashed GDB
4176 When examining a long double variable, GDB would get a segmentation
4177 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4178 IRIX long double values).
4182 A bug in the VAX stack code was causing problems with the "next"
4183 command. This problem has been fixed.
4185 *** Changes in GDB 6.2:
4187 * Fix for ``many threads''
4189 On GNU/Linux systems that use the NPTL threads library, a program
4190 rapidly creating and deleting threads would confuse GDB leading to the
4193 ptrace: No such process.
4194 thread_db_get_info: cannot get thread info: generic error
4196 This problem has been fixed.
4198 * "-async" and "-noasync" options removed.
4200 Support for the broken "-noasync" option has been removed (it caused
4203 * New ``start'' command.
4205 This command runs the program until the begining of the main procedure.
4207 * New BSD Kernel Data Access Library (libkvm) interface
4209 Using ``target kvm'' it is now possible to debug kernel core dumps and
4210 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4211 platforms. Currently supported (native-only) configurations are:
4213 FreeBSD/amd64 x86_64-*-freebsd*
4214 FreeBSD/i386 i?86-*-freebsd*
4215 NetBSD/i386 i?86-*-netbsd*
4216 NetBSD/m68k m68*-*-netbsd*
4217 NetBSD/sparc sparc-*-netbsd*
4218 OpenBSD/amd64 x86_64-*-openbsd*
4219 OpenBSD/i386 i?86-*-openbsd*
4220 OpenBSD/m68k m68*-openbsd*
4221 OpenBSD/sparc sparc-*-openbsd*
4223 * Signal trampoline code overhauled
4225 Many generic problems with GDB's signal handling code have been fixed.
4226 These include: backtraces through non-contiguous stacks; recognition
4227 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4228 call; backtrace through a signal trampoline; step into and out of
4229 signal handlers; and single-stepping in the signal trampoline.
4231 Please note that kernel bugs are a limiting factor here. These
4232 features have been shown to work on an s390 GNU/Linux system that
4233 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4235 * Cygwin support for DWARF 2 added.
4237 * New native configurations
4239 GNU/Linux/hppa hppa*-*-linux*
4240 OpenBSD/hppa hppa*-*-openbsd*
4241 OpenBSD/m68k m68*-*-openbsd*
4242 OpenBSD/m88k m88*-*-openbsd*
4243 OpenBSD/powerpc powerpc-*-openbsd*
4244 NetBSD/vax vax-*-netbsd*
4245 OpenBSD/vax vax-*-openbsd*
4247 * END-OF-LIFE frame compatibility module
4249 GDB's internal frame infrastructure has been completely rewritten.
4250 The new infrastructure making it possible to support key new features
4251 including DWARF 2 Call Frame Information. To aid in the task of
4252 migrating old configurations to this new infrastructure, a
4253 compatibility module, that allowed old configurations to continue to
4254 work, was also included.
4256 GDB 6.2 will be the last release to include this frame compatibility
4257 module. This change directly impacts the following configurations:
4267 Unless there is activity to revive these configurations, they will be
4268 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4270 * REMOVED configurations and files
4272 Sun 3, running SunOS 3 m68*-*-sunos3*
4273 Sun 3, running SunOS 4 m68*-*-sunos4*
4274 Sun 2, running SunOS 3 m68000-*-sunos3*
4275 Sun 2, running SunOS 4 m68000-*-sunos4*
4276 Motorola 680x0 running LynxOS m68*-*-lynxos*
4277 AT&T 3b1/Unix pc m68*-att-*
4278 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4279 decstation mips-dec-* mips-little-*
4280 riscos mips-*-riscos* mips-*-sysv*
4281 sonymips mips-sony-*
4282 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4284 *** Changes in GDB 6.1.1:
4286 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4288 The TUI (Text-mode User Interface) is now built as part of a default
4289 GDB configuration. It is enabled by either selecting the TUI with the
4290 command line option "-i=tui" or by running the separate "gdbtui"
4291 program. For more information on the TUI, see the manual "Debugging
4294 * Pending breakpoint support (also included in GDB 6.1)
4296 Support has been added to allow you to specify breakpoints in shared
4297 libraries that have not yet been loaded. If a breakpoint location
4298 cannot be found, and the "breakpoint pending" option is set to auto,
4299 GDB queries you if you wish to make the breakpoint pending on a future
4300 shared-library load. If and when GDB resolves the breakpoint symbol,
4301 the pending breakpoint is removed as one or more regular breakpoints
4304 Pending breakpoints are very useful for GCJ Java debugging.
4306 * Fixed ISO-C build problems
4308 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4309 non ISO-C code that stopped them being built using a more strict ISO-C
4310 compiler (e.g., IBM's C compiler).
4312 * Fixed build problem on IRIX 5
4314 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4315 wasn't able to compile compile on an IRIX 5 system.
4317 * Added execute permission to gdb/gdbserver/configure
4319 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4320 permission. This bug would cause configure to fail on a number of
4321 systems (Solaris, IRIX). Ref: server/519.
4323 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4325 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4326 has been updated to use constant array sizes.
4328 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4330 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4331 its generated DWARF Call Frame Info. This encoding was causing GDB to
4332 panic, that panic has been fixed. Ref: gdb/1628.
4334 * Fixed a problem when examining parameters in shared library code.
4336 When examining parameters in optimized shared library code generated
4337 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4338 not available''. GDB now correctly displays the variable's value.
4340 *** Changes in GDB 6.1:
4342 * Removed --with-mmalloc
4344 Support for the mmalloc memory manager has been removed, as it
4345 conflicted with the internal gdb byte cache.
4347 * Changes in AMD64 configurations
4349 The AMD64 target now includes the %cs and %ss registers. As a result
4350 the AMD64 remote protocol has changed; this affects the floating-point
4351 and SSE registers. If you rely on those registers for your debugging,
4352 you should upgrade gdbserver on the remote side.
4354 * Revised SPARC target
4356 The SPARC target has been completely revised, incorporating the
4357 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4358 support for LynxOS and SunOS 4 has been dropped. Calling functions
4359 from within GDB on operating systems with a non-executable stack
4360 (Solaris, OpenBSD) now works.
4364 GDB has a new C++ demangler which does a better job on the mangled
4365 names generated by current versions of g++. It also runs faster, so
4366 with this and other changes gdb should now start faster on large C++
4369 * DWARF 2 Location Expressions
4371 GDB support for location expressions has been extended to support function
4372 arguments and frame bases. Older versions of GDB could crash when they
4375 * C++ nested types and namespaces
4377 GDB's support for nested types and namespaces in C++ has been
4378 improved, especially if you use the DWARF 2 debugging format. (This
4379 is the default for recent versions of GCC on most platforms.)
4380 Specifically, if you have a class "Inner" defined within a class or
4381 namespace "Outer", then GDB realizes that the class's name is
4382 "Outer::Inner", not simply "Inner". This should greatly reduce the
4383 frequency of complaints about not finding RTTI symbols. In addition,
4384 if you are stopped at inside of a function defined within a namespace,
4385 GDB modifies its name lookup accordingly.
4387 * New native configurations
4389 NetBSD/amd64 x86_64-*-netbsd*
4390 OpenBSD/amd64 x86_64-*-openbsd*
4391 OpenBSD/alpha alpha*-*-openbsd*
4392 OpenBSD/sparc sparc-*-openbsd*
4393 OpenBSD/sparc64 sparc64-*-openbsd*
4395 * New debugging protocols
4397 M32R with SDI protocol m32r-*-elf*
4399 * "set prompt-escape-char" command deleted.
4401 The command "set prompt-escape-char" has been deleted. This command,
4402 and its very obscure effet on GDB's prompt, was never documented,
4403 tested, nor mentioned in the NEWS file.
4405 * OBSOLETE configurations and files
4407 Configurations that have been declared obsolete in this release have
4408 been commented out. Unless there is activity to revive these
4409 configurations, the next release of GDB will have their sources
4410 permanently REMOVED.
4412 Sun 3, running SunOS 3 m68*-*-sunos3*
4413 Sun 3, running SunOS 4 m68*-*-sunos4*
4414 Sun 2, running SunOS 3 m68000-*-sunos3*
4415 Sun 2, running SunOS 4 m68000-*-sunos4*
4416 Motorola 680x0 running LynxOS m68*-*-lynxos*
4417 AT&T 3b1/Unix pc m68*-att-*
4418 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4419 decstation mips-dec-* mips-little-*
4420 riscos mips-*-riscos* mips-*-sysv*
4421 sonymips mips-sony-*
4422 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4424 * REMOVED configurations and files
4426 SGI Irix-4.x mips-sgi-irix4 or iris4
4427 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4428 Z8000 simulator z8k-zilog-none or z8ksim
4429 Matsushita MN10200 w/simulator mn10200-*-*
4430 H8/500 simulator h8500-hitachi-hms or h8500hms
4431 HP/PA running BSD hppa*-*-bsd*
4432 HP/PA running OSF/1 hppa*-*-osf*
4433 HP/PA Pro target hppa*-*-pro*
4434 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4435 386BSD i[3456]86-*-bsd*
4436 Sequent family i[3456]86-sequent-sysv4*
4437 i[3456]86-sequent-sysv*
4438 i[3456]86-sequent-bsd*
4439 SPARC running LynxOS sparc-*-lynxos*
4440 SPARC running SunOS 4 sparc-*-sunos4*
4441 Tsqware Sparclet sparclet-*-*
4442 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4444 *** Changes in GDB 6.0:
4448 Support for debugging the Objective-C programming language has been
4449 integrated into GDB.
4451 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4453 DWARF 2's Call Frame Information makes available compiler generated
4454 information that more exactly describes the program's run-time stack.
4455 By using this information, GDB is able to provide more robust stack
4458 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4459 have been updated to use a new backtrace mechanism which includes
4460 DWARF 2 CFI support.
4464 GDB's remote protocol has been extended to include support for hosted
4465 file I/O (where the remote target uses GDB's file system). See GDB's
4466 remote protocol documentation for details.
4468 * All targets using the new architecture framework.
4470 All of GDB's targets have been updated to use the new internal
4471 architecture framework. The way is now open for future GDB releases
4472 to include cross-architecture native debugging support (i386 on amd64,
4475 * GNU/Linux's Thread Local Storage (TLS)
4477 GDB now includes support for for the GNU/Linux implementation of
4478 per-thread variables.
4480 * GNU/Linux's Native POSIX Thread Library (NPTL)
4482 GDB's thread code has been updated to work with either the new
4483 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4485 * Separate debug info.
4487 GDB, in conjunction with BINUTILS, now supports a mechanism for
4488 automatically loading debug information from a separate file. Instead
4489 of shipping full debug and non-debug versions of system libraries,
4490 system integrators can now instead ship just the stripped libraries
4491 and optional debug files.
4493 * DWARF 2 Location Expressions
4495 DWARF 2 Location Expressions allow the compiler to more completely
4496 describe the location of variables (even in optimized code) to the
4499 GDB now includes preliminary support for location expressions (support
4500 for DW_OP_piece is still missing).
4504 A number of long standing bugs that caused GDB to die while starting a
4505 Java application have been fixed. GDB's Java support is now
4506 considered "useable".
4508 * GNU/Linux support for fork, vfork, and exec.
4510 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4511 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4514 * GDB supports logging output to a file
4516 There are two new commands, "set logging" and "show logging", which can be
4517 used to capture GDB's output to a file.
4519 * The meaning of "detach" has changed for gdbserver
4521 The "detach" command will now resume the application, as documented. To
4522 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4525 * d10v, m68hc11 `regs' command deprecated
4527 The `info registers' command has been updated so that it displays the
4528 registers using a format identical to the old `regs' command.
4532 A new command, "maint set profile on/off", has been added. This command can
4533 be used to enable or disable profiling while running GDB, to profile a
4534 session or a set of commands. In addition there is a new configure switch,
4535 "--enable-profiling", which will cause GDB to be compiled with profiling
4536 data, for more informative profiling results.
4538 * Default MI syntax changed to "mi2".
4540 The default MI (machine interface) syntax, enabled by the command line
4541 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4542 "mi1", can be enabled by specifying the option "-i=mi1".
4544 Support for the original "mi0" syntax (included in GDB 5.0) has been
4547 Fix for gdb/192: removed extraneous space when displaying frame level.
4548 Fix for gdb/672: update changelist is now output in mi list format.
4549 Fix for gdb/702: a -var-assign that updates the value now shows up
4550 in a subsequent -var-update.
4552 * New native configurations.
4554 FreeBSD/amd64 x86_64-*-freebsd*
4556 * Multi-arched targets.
4558 HP/PA HPUX11 hppa*-*-hpux*
4559 Renesas M32R/D w/simulator m32r-*-elf*
4561 * OBSOLETE configurations and files
4563 Configurations that have been declared obsolete in this release have
4564 been commented out. Unless there is activity to revive these
4565 configurations, the next release of GDB will have their sources
4566 permanently REMOVED.
4568 Z8000 simulator z8k-zilog-none or z8ksim
4569 Matsushita MN10200 w/simulator mn10200-*-*
4570 H8/500 simulator h8500-hitachi-hms or h8500hms
4571 HP/PA running BSD hppa*-*-bsd*
4572 HP/PA running OSF/1 hppa*-*-osf*
4573 HP/PA Pro target hppa*-*-pro*
4574 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4575 Sequent family i[3456]86-sequent-sysv4*
4576 i[3456]86-sequent-sysv*
4577 i[3456]86-sequent-bsd*
4578 Tsqware Sparclet sparclet-*-*
4579 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4581 * REMOVED configurations and files
4584 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4585 IBM AIX PS/2 i[3456]86-*-aix
4586 i386 running Mach 3.0 i[3456]86-*-mach3*
4587 i386 running Mach i[3456]86-*-mach*
4588 i386 running OSF/1 i[3456]86-*osf1mk*
4589 HP/Apollo 68k Family m68*-apollo*-sysv*,
4591 m68*-hp-bsd*, m68*-hp-hpux*
4592 Argonaut Risc Chip (ARC) arc-*-*
4593 Mitsubishi D30V d30v-*-*
4594 Fujitsu FR30 fr30-*-elf*
4595 OS/9000 i[34]86-*-os9k
4596 I960 with MON960 i960-*-coff
4598 * MIPS $fp behavior changed
4600 The convenience variable $fp, for the MIPS, now consistently returns
4601 the address of the current frame's base. Previously, depending on the
4602 context, $fp could refer to either $sp or the current frame's base
4603 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4604 The GNU Source-Level Debugger''.
4606 *** Changes in GDB 5.3:
4608 * GNU/Linux shared library multi-threaded performance improved.
4610 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4611 `/proc', in preference to `ptrace' for memory reads. This may result
4612 in an improvement in the start-up time of multi-threaded, shared
4613 library applications when run under GDB. One GDB user writes: ``loads
4614 shared libs like mad''.
4616 * ``gdbserver'' now supports multi-threaded applications on some targets
4618 Support for debugging multi-threaded applications which use
4619 the GNU/Linux LinuxThreads package has been added for
4620 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4621 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4623 * GDB now supports C/C++ preprocessor macros.
4625 GDB now expands preprocessor macro invocations in C/C++ expressions,
4626 and provides various commands for showing macro definitions and how
4629 The new command `macro expand EXPRESSION' expands any macro
4630 invocations in expression, and shows the result.
4632 The new command `show macro MACRO-NAME' shows the definition of the
4633 macro named MACRO-NAME, and where it was defined.
4635 Most compilers don't include information about macros in the debugging
4636 information by default. In GCC 3.1, for example, you need to compile
4637 your program with the options `-gdwarf-2 -g3'. If the macro
4638 information is present in the executable, GDB will read it.
4640 * Multi-arched targets.
4642 DEC Alpha (partial) alpha*-*-*
4643 DEC VAX (partial) vax-*-*
4645 National Semiconductor NS32000 (partial) ns32k-*-*
4646 Motorola 68000 (partial) m68k-*-*
4647 Motorola MCORE mcore-*-*
4651 Fujitsu FRV architecture added by Red Hat frv*-*-*
4654 * New native configurations
4656 Alpha NetBSD alpha*-*-netbsd*
4657 SH NetBSD sh*-*-netbsdelf*
4658 MIPS NetBSD mips*-*-netbsd*
4659 UltraSPARC NetBSD sparc64-*-netbsd*
4661 * OBSOLETE configurations and files
4663 Configurations that have been declared obsolete in this release have
4664 been commented out. Unless there is activity to revive these
4665 configurations, the next release of GDB will have their sources
4666 permanently REMOVED.
4668 Mitsubishi D30V d30v-*-*
4669 OS/9000 i[34]86-*-os9k
4670 IBM AIX PS/2 i[3456]86-*-aix
4671 Fujitsu FR30 fr30-*-elf*
4672 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4673 Argonaut Risc Chip (ARC) arc-*-*
4674 i386 running Mach 3.0 i[3456]86-*-mach3*
4675 i386 running Mach i[3456]86-*-mach*
4676 i386 running OSF/1 i[3456]86-*osf1mk*
4677 HP/Apollo 68k Family m68*-apollo*-sysv*,
4679 m68*-hp-bsd*, m68*-hp-hpux*
4680 I960 with MON960 i960-*-coff
4682 * OBSOLETE languages
4684 CHILL, a Pascal like language used by telecommunications companies.
4686 * REMOVED configurations and files
4688 AMD 29k family via UDI a29k-amd-udi, udi29k
4689 A29K VxWorks a29k-*-vxworks
4690 AMD 29000 embedded, using EBMON a29k-none-none
4691 AMD 29000 embedded with COFF a29k-none-coff
4692 AMD 29000 embedded with a.out a29k-none-aout
4694 testsuite/gdb.hp/gdb.threads-hp/ directory
4696 * New command "set max-user-call-depth <nnn>"
4698 This command allows the user to limit the call depth of user-defined
4699 commands. The default is 1024.
4701 * Changes in FreeBSD/i386 native debugging.
4703 Support for the "generate-core-file" has been added.
4705 * New commands "dump", "append", and "restore".
4707 These commands allow data to be copied from target memory
4708 to a bfd-format or binary file (dump and append), and back
4709 from a file into memory (restore).
4711 * Improved "next/step" support on multi-processor Alpha Tru64.
4713 The previous single-step mechanism could cause unpredictable problems,
4714 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4715 of a software single-step mechanism prevents this.
4717 *** Changes in GDB 5.2.1:
4725 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4726 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4727 Fix, by Joel Brobecker imported from mainline.
4729 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4730 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4731 Fix, by Fred Fish, imported from mainline.
4733 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4734 Surprisingly enough, it works now.
4735 By Michal Ludvig, imported from mainline.
4737 i386 hardware watchpoint support:
4738 avoid misses on second run for some targets.
4739 By Pierre Muller, imported from mainline.
4741 *** Changes in GDB 5.2:
4743 * New command "set trust-readonly-sections on[off]".
4745 This command is a hint that tells gdb that read-only sections
4746 really are read-only (ie. that their contents will not change).
4747 In this mode, gdb will go to the object file rather than the
4748 target to read memory from read-only sections (such as ".text").
4749 This can be a significant performance improvement on some
4750 (notably embedded) targets.
4752 * New command "generate-core-file" (or "gcore").
4754 This new gdb command allows the user to drop a core file of the child
4755 process state at any time. So far it's been implemented only for
4756 GNU/Linux and Solaris, but should be relatively easily ported to other
4757 hosts. Argument is core file name (defaults to core.<pid>).
4759 * New command line option
4761 GDB now accepts --pid or -p followed by a process id.
4763 * Change in command line behavior -- corefiles vs. process ids.
4765 There is a subtle behavior in the way in which GDB handles
4766 command line arguments. The first non-flag argument is always
4767 a program to debug, but the second non-flag argument may either
4768 be a corefile or a process id. Previously, GDB would attempt to
4769 open the second argument as a corefile, and if that failed, would
4770 issue a superfluous error message and then attempt to attach it as
4771 a process. Now, if the second argument begins with a non-digit,
4772 it will be treated as a corefile. If it begins with a digit,
4773 GDB will attempt to attach it as a process, and if no such process
4774 is found, will then attempt to open it as a corefile.
4776 * Changes in ARM configurations.
4778 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4779 configuration is fully multi-arch.
4781 * New native configurations
4783 ARM NetBSD arm*-*-netbsd*
4784 x86 OpenBSD i[3456]86-*-openbsd*
4785 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4786 Sparc64 running FreeBSD sparc64-*-freebsd*
4790 Sanyo XStormy16 xstormy16-elf
4792 * OBSOLETE configurations and files
4794 Configurations that have been declared obsolete in this release have
4795 been commented out. Unless there is activity to revive these
4796 configurations, the next release of GDB will have their sources
4797 permanently REMOVED.
4799 AMD 29k family via UDI a29k-amd-udi, udi29k
4800 A29K VxWorks a29k-*-vxworks
4801 AMD 29000 embedded, using EBMON a29k-none-none
4802 AMD 29000 embedded with COFF a29k-none-coff
4803 AMD 29000 embedded with a.out a29k-none-aout
4805 testsuite/gdb.hp/gdb.threads-hp/ directory
4807 * REMOVED configurations and files
4809 TI TMS320C80 tic80-*-*
4811 PowerPC Solaris powerpcle-*-solaris*
4812 PowerPC Windows NT powerpcle-*-cygwin32
4813 PowerPC Netware powerpc-*-netware*
4814 Harris/CXUX m88k m88*-harris-cxux*
4815 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4816 ns32k-utek-sysv* ns32k-utek-*
4817 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4818 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4819 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4820 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4821 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4823 * Changes to command line processing
4825 The new `--args' feature can be used to specify command-line arguments
4826 for the inferior from gdb's command line.
4828 * Changes to key bindings
4830 There is a new `operate-and-get-next' function bound to `C-o'.
4832 *** Changes in GDB 5.1.1
4834 Fix compile problem on DJGPP.
4836 Fix a problem with floating-point registers on the i386 being
4839 Fix to stop GDB crashing on .debug_str debug info.
4841 Numerous documentation fixes.
4843 Numerous testsuite fixes.
4845 *** Changes in GDB 5.1:
4847 * New native configurations
4849 Alpha FreeBSD alpha*-*-freebsd*
4850 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4851 MIPS GNU/Linux mips*-*-linux*
4852 MIPS SGI Irix 6.x mips*-sgi-irix6*
4853 ia64 AIX ia64-*-aix*
4854 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4858 Motorola 68HC11 and 68HC12 m68hc11-elf
4860 UltraSparc running GNU/Linux sparc64-*-linux*
4862 * OBSOLETE configurations and files
4864 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4865 Harris/CXUX m88k m88*-harris-cxux*
4866 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4867 ns32k-utek-sysv* ns32k-utek-*
4868 TI TMS320C80 tic80-*-*
4870 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4871 PowerPC Solaris powerpcle-*-solaris*
4872 PowerPC Windows NT powerpcle-*-cygwin32
4873 PowerPC Netware powerpc-*-netware*
4874 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4875 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4876 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4877 Apple Macintosh (MPW) host N/A
4879 stuff.c (Program to stuff files into a specially prepared space in kdb)
4880 kdb-start.c (Main loop for the standalone kernel debugger)
4882 Configurations that have been declared obsolete in this release have
4883 been commented out. Unless there is activity to revive these
4884 configurations, the next release of GDB will have their sources
4885 permanently REMOVED.
4887 * REMOVED configurations and files
4889 Altos 3068 m68*-altos-*
4890 Convex c1-*-*, c2-*-*
4892 ARM RISCix arm-*-* (as host)
4896 * GDB has been converted to ISO C.
4898 GDB's source code has been converted to ISO C. In particular, the
4899 sources are fully protoized, and rely on standard headers being
4904 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4906 * The MI enabled by default.
4908 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4909 revised and enabled by default. Packages which use GDB as a debugging
4910 engine behind a UI or another front end are encouraged to switch to
4911 using the GDB/MI interface, instead of the old annotations interface
4912 which is now deprecated.
4914 * Support for debugging Pascal programs.
4916 GDB now includes support for debugging Pascal programs. The following
4917 main features are supported:
4919 - Pascal-specific data types such as sets;
4921 - automatic recognition of Pascal sources based on file-name
4924 - Pascal-style display of data types, variables, and functions;
4926 - a Pascal expression parser.
4928 However, some important features are not yet supported.
4930 - Pascal string operations are not supported at all;
4932 - there are some problems with boolean types;
4934 - Pascal type hexadecimal constants are not supported
4935 because they conflict with the internal variables format;
4937 - support for Pascal objects and classes is not full yet;
4939 - unlike Pascal, GDB is case-sensitive for symbol names.
4941 * Changes in completion.
4943 Commands such as `shell', `run' and `set args', which pass arguments
4944 to inferior programs, now complete on file names, similar to what
4945 users expect at the shell prompt.
4947 Commands which accept locations, such as `disassemble', `print',
4948 `breakpoint', `until', etc. now complete on filenames as well as
4949 program symbols. Thus, if you type "break foob TAB", and the source
4950 files linked into the programs include `foobar.c', that file name will
4951 be one of the candidates for completion. However, file names are not
4952 considered for completion after you typed a colon that delimits a file
4953 name from a name of a function in that file, as in "break foo.c:bar".
4955 `set demangle-style' completes on available demangling styles.
4957 * New platform-independent commands:
4959 It is now possible to define a post-hook for a command as well as a
4960 hook that runs before the command. For more details, see the
4961 documentation of `hookpost' in the GDB manual.
4963 * Changes in GNU/Linux native debugging.
4965 Support for debugging multi-threaded programs has been completely
4966 revised for all platforms except m68k and sparc. You can now debug as
4967 many threads as your system allows you to have.
4969 Attach/detach is supported for multi-threaded programs.
4971 Support for SSE registers was added for x86. This doesn't work for
4972 multi-threaded programs though.
4974 * Changes in MIPS configurations.
4976 Multi-arch support is enabled for all MIPS configurations.
4978 GDB can now be built as native debugger on SGI Irix 6.x systems for
4979 debugging n32 executables. (Debugging 64-bit executables is not yet
4982 * Unified support for hardware watchpoints in all x86 configurations.
4984 Most (if not all) native x86 configurations support hardware-assisted
4985 breakpoints and watchpoints in a unified manner. This support
4986 implements debug register sharing between watchpoints, which allows to
4987 put a virtually infinite number of watchpoints on the same address,
4988 and also supports watching regions up to 16 bytes with several debug
4991 The new maintenance command `maintenance show-debug-regs' toggles
4992 debugging print-outs in functions that insert, remove, and test
4993 watchpoints and hardware breakpoints.
4995 * Changes in the DJGPP native configuration.
4997 New command ``info dos sysinfo'' displays assorted information about
4998 the CPU, OS, memory, and DPMI server.
5000 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
5001 display information about segment descriptors stored in GDT, LDT, and
5004 New commands ``info dos pde'' and ``info dos pte'' display entries
5005 from Page Directory and Page Tables (for now works with CWSDPMI only).
5006 New command ``info dos address-pte'' displays the Page Table entry for
5007 a given linear address.
5009 GDB can now pass command lines longer than 126 characters to the
5010 program being debugged (requires an update to the libdbg.a library
5011 which is part of the DJGPP development kit).
5013 DWARF2 debug info is now supported.
5015 It is now possible to `step' and `next' through calls to `longjmp'.
5017 * Changes in documentation.
5019 All GDB documentation was converted to GFDL, the GNU Free
5020 Documentation License.
5022 Tracepoints-related commands are now fully documented in the GDB
5025 TUI, the Text-mode User Interface, is now documented in the manual.
5027 Tracepoints-related commands are now fully documented in the GDB
5030 The "GDB Internals" manual now has an index. It also includes
5031 documentation of `ui_out' functions, GDB coding standards, x86
5032 hardware watchpoints, and memory region attributes.
5034 * GDB's version number moved to ``version.in''
5036 The Makefile variable VERSION has been replaced by the file
5037 ``version.in''. People creating GDB distributions should update the
5038 contents of this file.
5042 GUD support is now a standard part of the EMACS distribution.
5044 *** Changes in GDB 5.0:
5046 * Improved support for debugging FP programs on x86 targets
5048 Unified and much-improved support for debugging floating-point
5049 programs on all x86 targets. In particular, ``info float'' now
5050 displays the FP registers in the same format on all x86 targets, with
5051 greater level of detail.
5053 * Improvements and bugfixes in hardware-assisted watchpoints
5055 It is now possible to watch array elements, struct members, and
5056 bitfields with hardware-assisted watchpoints. Data-read watchpoints
5057 on x86 targets no longer erroneously trigger when the address is
5060 * Improvements in the native DJGPP version of GDB
5062 The distribution now includes all the scripts and auxiliary files
5063 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5064 machines ``out of the box''.
5066 The DJGPP version can now debug programs that use signals. It is
5067 possible to catch signals that happened in the debuggee, deliver
5068 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5069 would kill the program being debugged.) Programs that hook hardware
5070 interrupts (keyboard, timer, etc.) can also be debugged.
5072 It is now possible to debug DJGPP programs that redirect their
5073 standard handles or switch them to raw (as opposed to cooked) mode, or
5074 even close them. The command ``run < foo > bar'' works as expected,
5075 and ``info terminal'' reports useful information about the debuggee's
5076 terminal, including raw/cooked mode, redirection, etc.
5078 The DJGPP version now uses termios functions for console I/O, which
5079 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5082 DOS-style file names with drive letters are now fully supported by
5085 It is now possible to debug DJGPP programs that switch their working
5086 directory. It is also possible to rerun the debuggee any number of
5087 times without restarting GDB; thus, you can use the same setup,
5088 breakpoints, etc. for many debugging sessions.
5090 * New native configurations
5092 ARM GNU/Linux arm*-*-linux*
5093 PowerPC GNU/Linux powerpc-*-linux*
5097 Motorola MCore mcore-*-*
5098 x86 VxWorks i[3456]86-*-vxworks*
5099 PowerPC VxWorks powerpc-*-vxworks*
5100 TI TMS320C80 tic80-*-*
5102 * OBSOLETE configurations
5104 Altos 3068 m68*-altos-*
5105 Convex c1-*-*, c2-*-*
5107 ARM RISCix arm-*-* (as host)
5110 Configurations that have been declared obsolete will be commented out,
5111 but the code will be left in place. If there is no activity to revive
5112 these configurations before the next release of GDB, the sources will
5113 be permanently REMOVED.
5115 * Gould support removed
5117 Support for the Gould PowerNode and NP1 has been removed.
5119 * New features for SVR4
5121 On SVR4 native platforms (such as Solaris), if you attach to a process
5122 without first loading a symbol file, GDB will now attempt to locate and
5123 load symbols from the running process's executable file.
5125 * Many C++ enhancements
5127 C++ support has been greatly improved. Overload resolution now works properly
5128 in almost all cases. RTTI support is on the way.
5130 * Remote targets can connect to a sub-program
5132 A popen(3) style serial-device has been added. This device starts a
5133 sub-process (such as a stand-alone simulator) and then communicates
5134 with that. The sub-program to run is specified using the syntax
5135 ``|<program> <args>'' vis:
5137 (gdb) set remotedebug 1
5138 (gdb) target extended-remote |mn10300-elf-sim program-args
5140 * MIPS 64 remote protocol
5142 A long standing bug in the mips64 remote protocol where by GDB
5143 expected certain 32 bit registers (ex SR) to be transfered as 32
5144 instead of 64 bits has been fixed.
5146 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5147 added to provide backward compatibility with older versions of GDB.
5149 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5151 The command ``set remotebinarydownload'' command has been replaced by
5152 ``set remote X-packet''. Other commands in ``set remote'' family
5153 include ``set remote P-packet''.
5155 * Breakpoint commands accept ranges.
5157 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5158 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5159 ``tracepoint passcount'' also accepts a range of tracepoints.
5161 * ``apropos'' command added.
5163 The ``apropos'' command searches through command names and
5164 documentation strings, printing out matches, making it much easier to
5165 try to find a command that does what you are looking for.
5169 A new machine oriented interface (MI) has been added to GDB. This
5170 interface is designed for debug environments running GDB as a separate
5171 process. This is part of the long term libGDB project. See the
5172 "GDB/MI" chapter of the GDB manual for further information. It can be
5173 enabled by configuring with:
5175 .../configure --enable-gdbmi
5177 *** Changes in GDB-4.18:
5179 * New native configurations
5181 HP-UX 10.20 hppa*-*-hpux10.20
5182 HP-UX 11.x hppa*-*-hpux11.0*
5183 M68K GNU/Linux m68*-*-linux*
5187 Fujitsu FR30 fr30-*-elf*
5188 Intel StrongARM strongarm-*-*
5189 Mitsubishi D30V d30v-*-*
5191 * OBSOLETE configurations
5193 Gould PowerNode, NP1 np1-*-*, pn-*-*
5195 Configurations that have been declared obsolete will be commented out,
5196 but the code will be left in place. If there is no activity to revive
5197 these configurations before the next release of GDB, the sources will
5198 be permanently REMOVED.
5202 As a compatibility experiment, GDB's source files buildsym.h and
5203 buildsym.c have been converted to pure standard C, no longer
5204 containing any K&R compatibility code. We believe that all systems in
5205 use today either come with a standard C compiler, or have a GCC port
5206 available. If this is not true, please report the affected
5207 configuration to bug-gdb@gnu.org immediately. See the README file for
5208 information about getting a standard C compiler if you don't have one
5213 GDB now uses readline 2.2.
5215 * set extension-language
5217 You can now control the mapping between filename extensions and source
5218 languages by using the `set extension-language' command. For instance,
5219 you can ask GDB to treat .c files as C++ by saying
5220 set extension-language .c c++
5221 The command `info extensions' lists all of the recognized extensions
5222 and their associated languages.
5224 * Setting processor type for PowerPC and RS/6000
5226 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5227 you can use the `set processor' command to specify what variant of the
5228 PowerPC family you are debugging. The command
5232 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5233 following PowerPC and RS6000 variants:
5235 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5236 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5238 403GC IBM PowerPC 403GC
5239 505 Motorola PowerPC 505
5240 860 Motorola PowerPC 860 or 850
5241 601 Motorola PowerPC 601
5242 602 Motorola PowerPC 602
5243 603 Motorola/IBM PowerPC 603 or 603e
5244 604 Motorola PowerPC 604 or 604e
5245 750 Motorola/IBM PowerPC 750 or 750
5247 At the moment, this command just tells GDB what to name the
5248 special-purpose processor registers. Since almost all the affected
5249 registers are inaccessible to user-level programs, this command is
5250 only useful for remote debugging in its present form.
5254 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5255 more extensive support for HP-UX. Added features include shared
5256 library support, kernel threads and hardware watchpoints for 11.00,
5257 support for HP's ANSI C and C++ compilers, and a compatibility mode
5258 for xdb and dbx commands.
5262 HP's donation includes the new concept of catchpoints, which is a
5263 generalization of the old catch command. On HP-UX, it is now possible
5264 to catch exec, fork, and vfork, as well as library loading.
5266 This means that the existing catch command has changed; its first
5267 argument now specifies the type of catch to be set up. See the
5268 output of "help catch" for a list of catchpoint types.
5270 * Debugging across forks
5272 On HP-UX, you can choose which process to debug when a fork() happens
5277 HP has donated a curses-based terminal user interface (TUI). To get
5278 it, build with --enable-tui. Although this can be enabled for any
5279 configuration, at present it only works for native HP debugging.
5281 * GDB remote protocol additions
5283 A new protocol packet 'X' that writes binary data is now available.
5284 Default behavior is to try 'X', then drop back to 'M' if the stub
5285 fails to respond. The settable variable `remotebinarydownload'
5286 allows explicit control over the use of 'X'.
5288 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5289 full 64-bit address. The command
5291 set remoteaddresssize 32
5293 can be used to revert to the old behaviour. For existing remote stubs
5294 the change should not be noticed, as the additional address information
5297 In order to assist in debugging stubs, you may use the maintenance
5298 command `packet' to send any text string to the stub. For instance,
5300 maint packet heythere
5302 sends the packet "$heythere#<checksum>". Note that it is very easy to
5303 disrupt a debugging session by sending the wrong packet at the wrong
5306 The compare-sections command allows you to compare section data on the
5307 target to what is in the executable file without uploading or
5308 downloading, by comparing CRC checksums.
5310 * Tracing can collect general expressions
5312 You may now collect general expressions at tracepoints. This requires
5313 further additions to the target-side stub; see tracepoint.c and
5314 doc/agentexpr.texi for further details.
5316 * mask-address variable for Mips
5318 For Mips targets, you may control the zeroing of the upper 32 bits of
5319 a 64-bit address by entering `set mask-address on'. This is mainly
5320 of interest to users of embedded R4xxx and R5xxx processors.
5322 * Higher serial baud rates
5324 GDB's serial code now allows you to specify baud rates 57600, 115200,
5325 230400, and 460800 baud. (Note that your host system may not be able
5326 to achieve all of these rates.)
5330 The i960 configuration now includes an initial implementation of a
5331 builtin simulator, contributed by Jim Wilson.
5334 *** Changes in GDB-4.17:
5336 * New native configurations
5338 Alpha GNU/Linux alpha*-*-linux*
5339 Unixware 2.x i[3456]86-unixware2*
5340 Irix 6.x mips*-sgi-irix6*
5341 PowerPC GNU/Linux powerpc-*-linux*
5342 PowerPC Solaris powerpcle-*-solaris*
5343 Sparc GNU/Linux sparc-*-linux*
5344 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5348 Argonaut Risc Chip (ARC) arc-*-*
5349 Hitachi H8/300S h8300*-*-*
5350 Matsushita MN10200 w/simulator mn10200-*-*
5351 Matsushita MN10300 w/simulator mn10300-*-*
5352 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5353 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5354 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5355 Mitsubishi D10V w/simulator d10v-*-*
5356 Mitsubishi M32R/D w/simulator m32r-*-elf*
5357 Tsqware Sparclet sparclet-*-*
5358 NEC V850 w/simulator v850-*-*
5360 * New debugging protocols
5362 ARM with RDI protocol arm*-*-*
5363 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5364 DDB and LSI variants of PMON protocol mips*-*-*
5365 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5366 PowerPC with SDS protocol powerpc{,le}-*-eabi
5367 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5371 All configurations can now understand and use the DWARF 2 debugging
5372 format. The choice is automatic, if the symbol file contains DWARF 2
5377 GDB now includes basic Java language support. This support is
5378 only useful with Java compilers that produce native machine code.
5380 * solib-absolute-prefix and solib-search-path
5382 For SunOS and SVR4 shared libraries, you may now set the prefix for
5383 loading absolute shared library symbol files, and the search path for
5384 locating non-absolute shared library symbol files.
5386 * Live range splitting
5388 GDB can now effectively debug code for which GCC has performed live
5389 range splitting as part of its optimization. See gdb/doc/LRS for
5390 more details on the expected format of the stabs information.
5394 GDB's support for the GNU Hurd, including thread debugging, has been
5395 updated to work with current versions of the Hurd.
5399 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5400 instruction set. ARM GDB automatically detects when Thumb
5401 instructions are in use, and adjusts disassembly and backtracing
5406 GDB's MIPS target configurations now handle the MIP16 16-bit
5411 GDB now includes support for overlays; if an executable has been
5412 linked such that multiple sections are based at the same address, GDB
5413 will decide which section to use for symbolic info. You can choose to
5414 control the decision manually, using overlay commands, or implement
5415 additional target-side support and use "overlay load-target" to bring
5416 in the overlay mapping. Do "help overlay" for more detail.
5420 The command "info symbol <address>" displays information about
5421 the symbol at the specified address.
5425 The standard remote protocol now includes an extension that allows
5426 asynchronous collection and display of trace data. This requires
5427 extensive support in the target-side debugging stub. Tracing mode
5428 includes a new interaction mode in GDB and new commands: see the
5429 file tracepoint.c for more details.
5433 Configurations for embedded MIPS now include a simulator contributed
5434 by Cygnus Solutions. The simulator supports the instruction sets
5435 of most MIPS variants.
5439 Sparc configurations may now include the ERC32 simulator contributed
5440 by the European Space Agency. The simulator is not built into
5441 Sparc targets by default; configure with --enable-sim to include it.
5445 For target configurations that may include multiple variants of a
5446 basic architecture (such as MIPS and SH), you may now set the
5447 architecture explicitly. "set arch" sets, "info arch" lists
5448 the possible architectures.
5450 *** Changes in GDB-4.16:
5452 * New native configurations
5454 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5455 M68K NetBSD m68k-*-netbsd*
5456 PowerPC AIX 4.x powerpc-*-aix*
5457 PowerPC MacOS powerpc-*-macos*
5458 PowerPC Windows NT powerpcle-*-cygwin32
5459 RS/6000 AIX 4.x rs6000-*-aix4*
5463 ARM with RDP protocol arm-*-*
5464 I960 with MON960 i960-*-coff
5465 MIPS VxWorks mips*-*-vxworks*
5466 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5467 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5469 Matra Sparclet sparclet-*-*
5473 The powerpc-eabi configuration now includes the PSIM simulator,
5474 contributed by Andrew Cagney, with assistance from Mike Meissner.
5475 PSIM is a very elaborate model of the PowerPC, including not only
5476 basic instruction set execution, but also details of execution unit
5477 performance and I/O hardware. See sim/ppc/README for more details.
5481 GDB now works with Solaris 2.5.
5483 * Windows 95/NT native
5485 GDB will now work as a native debugger on Windows 95 and Windows NT.
5486 To build it from source, you must use the "gnu-win32" environment,
5487 which uses a DLL to emulate enough of Unix to run the GNU tools.
5488 Further information, binaries, and sources are available at
5489 ftp.cygnus.com, under pub/gnu-win32.
5491 * dont-repeat command
5493 If a user-defined command includes the command `dont-repeat', then the
5494 command will not be repeated if the user just types return. This is
5495 useful if the command is time-consuming to run, so that accidental
5496 extra keystrokes don't run the same command many times.
5498 * Send break instead of ^C
5500 The standard remote protocol now includes an option to send a break
5501 rather than a ^C to the target in order to interrupt it. By default,
5502 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5504 * Remote protocol timeout
5506 The standard remote protocol includes a new variable `remotetimeout'
5507 that allows you to set the number of seconds before GDB gives up trying
5508 to read from the target. The default value is 2.
5510 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5512 By default GDB will automatically keep track of objects as they are
5513 loaded and unloaded by the dynamic linker. By using the command `set
5514 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5515 when shared library events occur, thus allowing you to set breakpoints
5516 in shared libraries which are explicitly loaded by the inferior.
5518 Note this feature does not work on hpux8. On hpux9 you must link
5519 /usr/lib/end.o into your program. This feature should work
5520 automatically on hpux10.
5522 * Irix 5.x hardware watchpoint support
5524 Irix 5 configurations now support the use of hardware watchpoints.
5526 * Mips protocol "SYN garbage limit"
5528 When debugging a Mips target using the `target mips' protocol, you
5529 may set the number of characters that GDB will ignore by setting
5530 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5531 every character. The default value is 1050.
5533 * Recording and replaying remote debug sessions
5535 If you set `remotelogfile' to the name of a file, gdb will write to it
5536 a recording of a remote debug session. This recording may then be
5537 replayed back to gdb using "gdbreplay". See gdbserver/README for
5538 details. This is useful when you have a problem with GDB while doing
5539 remote debugging; you can make a recording of the session and send it
5540 to someone else, who can then recreate the problem.
5542 * Speedups for remote debugging
5544 GDB includes speedups for downloading and stepping MIPS systems using
5545 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5546 and more efficient S-record downloading.
5548 * Memory use reductions and statistics collection
5550 GDB now uses less memory and reports statistics about memory usage.
5551 Try the `maint print statistics' command, for example.
5553 *** Changes in GDB-4.15:
5555 * Psymtabs for XCOFF
5557 The symbol reader for AIX GDB now uses partial symbol tables. This
5558 can greatly improve startup time, especially for large executables.
5560 * Remote targets use caching
5562 Remote targets now use a data cache to speed up communication with the
5563 remote side. The data cache could lead to incorrect results because
5564 it doesn't know about volatile variables, thus making it impossible to
5565 debug targets which use memory mapped I/O devices. `set remotecache
5566 off' turns the the data cache off.
5568 * Remote targets may have threads
5570 The standard remote protocol now includes support for multiple threads
5571 in the target system, using new protocol commands 'H' and 'T'. See
5572 gdb/remote.c for details.
5576 If GDB is configured with `--enable-netrom', then it will include
5577 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5578 acts as though it is a bank of ROM on the target board, but you can
5579 write into it over the network. GDB's support consists only of
5580 support for fast loading into the emulated ROM; to debug, you must use
5581 another protocol, such as standard remote protocol. The usual
5582 sequence is something like
5584 target nrom <netrom-hostname>
5586 target remote <netrom-hostname>:1235
5590 GDB now includes support for the Apple Macintosh, as a host only. It
5591 may be run as either an MPW tool or as a standalone application, and
5592 it can debug through the serial port. All the usual GDB commands are
5593 available, but to the target command, you must supply "serial" as the
5594 device type instead of "/dev/ttyXX". See mpw-README in the main
5595 directory for more information on how to build. The MPW configuration
5596 scripts */mpw-config.in support only a few targets, and only the
5597 mips-idt-ecoff target has been tested.
5601 GDB configuration now uses autoconf. This is not user-visible,
5602 but does simplify configuration and building.
5606 GDB now supports hpux10.
5608 *** Changes in GDB-4.14:
5610 * New native configurations
5612 x86 FreeBSD i[345]86-*-freebsd
5613 x86 NetBSD i[345]86-*-netbsd
5614 NS32k NetBSD ns32k-*-netbsd
5615 Sparc NetBSD sparc-*-netbsd
5619 A29K VxWorks a29k-*-vxworks
5620 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5621 CPU32 EST-300 emulator m68*-*-est*
5622 PowerPC ELF powerpc-*-elf
5625 * Alpha OSF/1 support for procfs
5627 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5628 possible to attach to running processes. As the mounting of the /proc
5629 filesystem is optional on the Alpha, GDB automatically determines
5630 the availability of /proc during startup. This can lead to problems
5631 if /proc is unmounted after GDB has been started.
5633 * Arguments to user-defined commands
5635 User commands may accept up to 10 arguments separated by whitespace.
5636 Arguments are accessed within the user command via $arg0..$arg9. A
5639 print $arg0 + $arg1 + $arg2
5641 To execute the command use:
5644 Defines the command "adder" which prints the sum of its three arguments.
5645 Note the arguments are text substitutions, so they may reference variables,
5646 use complex expressions, or even perform inferior function calls.
5648 * New `if' and `while' commands
5650 This makes it possible to write more sophisticated user-defined
5651 commands. Both commands take a single argument, which is the
5652 expression to evaluate, and must be followed by the commands to
5653 execute, one per line, if the expression is nonzero, the list being
5654 terminated by the word `end'. The `if' command list may include an
5655 `else' word, which causes the following commands to be executed only
5656 if the expression is zero.
5658 * Fortran source language mode
5660 GDB now includes partial support for Fortran 77. It will recognize
5661 Fortran programs and can evaluate a subset of Fortran expressions, but
5662 variables and functions may not be handled correctly. GDB will work
5663 with G77, but does not yet know much about symbols emitted by other
5666 * Better HPUX support
5668 Most debugging facilities now work on dynamic executables for HPPAs
5669 running hpux9 or later. You can attach to running dynamically linked
5670 processes, but by default the dynamic libraries will be read-only, so
5671 for instance you won't be able to put breakpoints in them. To change
5672 that behavior do the following before running the program:
5678 This will cause the libraries to be mapped private and read-write.
5679 To revert to the normal behavior, do this:
5685 You cannot set breakpoints or examine data in the library until after
5686 the library is loaded if the function/data symbols do not have
5689 GDB can now also read debug symbols produced by the HP C compiler on
5690 HPPAs (sorry, no C++, Fortran or 68k support).
5692 * Target byte order now dynamically selectable
5694 You can choose which byte order to use with a target system, via the
5695 commands "set endian big" and "set endian little", and you can see the
5696 current setting by using "show endian". You can also give the command
5697 "set endian auto", in which case GDB will use the byte order
5698 associated with the executable. Currently, only embedded MIPS
5699 configurations support dynamic selection of target byte order.
5701 * New DOS host serial code
5703 This version uses DPMI interrupts to handle buffered I/O, so you
5704 no longer need to run asynctsr when debugging boards connected to
5707 *** Changes in GDB-4.13:
5709 * New "complete" command
5711 This lists all the possible completions for the rest of the line, if it
5712 were to be given as a command itself. This is intended for use by emacs.
5714 * Trailing space optional in prompt
5716 "set prompt" no longer adds a space for you after the prompt you set. This
5717 allows you to set a prompt which ends in a space or one that does not.
5719 * Breakpoint hit counts
5721 "info break" now displays a count of the number of times the breakpoint
5722 has been hit. This is especially useful in conjunction with "ignore"; you
5723 can ignore a large number of breakpoint hits, look at the breakpoint info
5724 to see how many times the breakpoint was hit, then run again, ignoring one
5725 less than that number, and this will get you quickly to the last hit of
5728 * Ability to stop printing at NULL character
5730 "set print null-stop" will cause GDB to stop printing the characters of
5731 an array when the first NULL is encountered. This is useful when large
5732 arrays actually contain only short strings.
5734 * Shared library breakpoints
5736 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5737 breakpoints in shared libraries before the executable is run.
5739 * Hardware watchpoints
5741 There is a new hardware breakpoint for the watch command for sparclite
5742 targets. See gdb/sparclite/hw_breakpoint.note.
5744 Hardware watchpoints are also now supported under GNU/Linux.
5748 Annotations have been added. These are for use with graphical interfaces,
5749 and are still experimental. Currently only gdba.el uses these.
5751 * Improved Irix 5 support
5753 GDB now works properly with Irix 5.2.
5755 * Improved HPPA support
5757 GDB now works properly with the latest GCC and GAS.
5759 * New native configurations
5761 Sequent PTX4 i[34]86-sequent-ptx4
5762 HPPA running OSF/1 hppa*-*-osf*
5763 Atari TT running SVR4 m68*-*-sysv4*
5764 RS/6000 LynxOS rs6000-*-lynxos*
5768 OS/9000 i[34]86-*-os9k
5769 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5772 * Hitachi SH7000 and E7000-PC ICE support
5774 There is now support for communicating with the Hitachi E7000-PC ICE.
5775 This is available automatically when GDB is configured for the SH.
5779 As usual, a variety of small fixes and improvements, both generic
5780 and configuration-specific. See the ChangeLog for more detail.
5782 *** Changes in GDB-4.12:
5784 * Irix 5 is now supported
5788 GDB-4.12 on the HPPA has a number of changes which make it unable
5789 to debug the output from the currently released versions of GCC and
5790 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5791 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5792 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5795 *** Changes in GDB-4.11:
5797 * User visible changes:
5801 The "set remotedebug" option is now consistent between the mips remote
5802 target, remote targets using the gdb-specific protocol, UDI (AMD's
5803 debug protocol for the 29k) and the 88k bug monitor. It is now an
5804 integer specifying a debug level (normally 0 or 1, but 2 means more
5805 debugging info for the mips target).
5807 * DEC Alpha native support
5809 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5810 debug info, but GDB works fairly well with the DEC compiler and should
5811 work with a future GCC release. See the README file for a few
5812 Alpha-specific notes.
5814 * Preliminary thread implementation
5816 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5818 * LynxOS native and target support for 386
5820 This release has been hosted on LynxOS 2.2, and also can be configured
5821 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5824 * Improvements in C++ mangling/demangling.
5826 This release has much better g++ debugging, specifically in name
5827 mangling/demangling, virtual function calls, print virtual table,
5828 call methods, ...etc.
5830 *** Changes in GDB-4.10:
5832 * User visible changes:
5834 Remote debugging using the GDB-specific (`target remote') protocol now
5835 supports the `load' command. This is only useful if you have some
5836 other way of getting the stub to the target system, and you can put it
5837 somewhere in memory where it won't get clobbered by the download.
5839 Filename completion now works.
5841 When run under emacs mode, the "info line" command now causes the
5842 arrow to point to the line specified. Also, "info line" prints
5843 addresses in symbolic form (as well as hex).
5845 All vxworks based targets now support a user settable option, called
5846 vxworks-timeout. This option represents the number of seconds gdb
5847 should wait for responses to rpc's. You might want to use this if
5848 your vxworks target is, perhaps, a slow software simulator or happens
5849 to be on the far side of a thin network line.
5853 This release contains support for using a DEC alpha as a GDB host for
5854 cross debugging. Native alpha debugging is not supported yet.
5857 *** Changes in GDB-4.9:
5861 This is the first GDB release which is accompanied by a matching testsuite.
5862 The testsuite requires installation of dejagnu, which should be available
5863 via ftp from most sites that carry GNU software.
5867 'Cfront' style demangling has had its name changed to 'ARM' style, to
5868 emphasize that it was written from the specifications in the C++ Annotated
5869 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5870 disclaimers, it still generated too much confusion with users attempting to
5871 use gdb with AT&T cfront.
5875 GDB now uses a standard remote interface to a simulator library.
5876 So far, the library contains simulators for the Zilog Z8001/2, the
5877 Hitachi H8/300, H8/500 and Super-H.
5879 * New targets supported
5881 H8/300 simulator h8300-hitachi-hms or h8300hms
5882 H8/500 simulator h8500-hitachi-hms or h8500hms
5883 SH simulator sh-hitachi-hms or sh
5884 Z8000 simulator z8k-zilog-none or z8ksim
5885 IDT MIPS board over serial line mips-idt-ecoff
5887 Cross-debugging to GO32 targets is supported. It requires a custom
5888 version of the i386-stub.c module which is integrated with the
5889 GO32 memory extender.
5891 * New remote protocols
5893 MIPS remote debugging protocol.
5895 * New source languages supported
5897 This version includes preliminary support for Chill, a Pascal like language
5898 used by telecommunications companies. Chill support is also being integrated
5899 into the GNU compiler, but we don't know when it will be publically available.
5902 *** Changes in GDB-4.8:
5904 * HP Precision Architecture supported
5906 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5907 version of this support was available as a set of patches from the
5908 University of Utah. GDB does not support debugging of programs
5909 compiled with the HP compiler, because HP will not document their file
5910 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5911 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5913 Many problems in the preliminary version have been fixed.
5915 * Faster and better demangling
5917 We have improved template demangling and fixed numerous bugs in the GNU style
5918 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5919 character types (wchar_t) are now supported. Demangling of each symbol is now
5920 only done once, and is cached when the symbol table for a file is read in.
5921 This results in a small increase in memory usage for C programs, a moderate
5922 increase in memory usage for C++ programs, and a fantastic speedup in
5925 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5926 from the specifications in the Annotated Reference Manual, which AT&T's
5927 compiler does not actually implement.
5929 * G++ multiple inheritance compiler problem
5931 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5932 inheritance lattices was reworked to properly discover ambiguities. We
5933 recently found an example which causes this new algorithm to fail in a
5934 very subtle way, producing bad debug information for those classes.
5935 The file 'gcc.patch' (in this directory) can be applied to gcc to
5936 circumvent the problem. A future GCC release will contain a complete
5939 The previous G++ debug info problem (mentioned below for the gdb-4.7
5940 release) is fixed in gcc version 2.3.2.
5942 * Improved configure script
5944 The `configure' script will now attempt to guess your system type if
5945 you don't supply a host system type. The old scheme of supplying a
5946 host system triplet is preferable over using this. All the magic is
5947 done in the new `config.guess' script. Examine it for details.
5949 We have also brought our configure script much more in line with the FSF's
5950 version. It now supports the --with-xxx options. In particular,
5951 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5952 The resulting GDB will not be able to read arbitrary object file formats --
5953 only the format ``expected'' to be used on the configured target system.
5954 We hope to make this the default in a future release.
5956 * Documentation improvements
5958 There's new internal documentation on how to modify GDB, and how to
5959 produce clean changes to the code. We implore people to read it
5960 before submitting changes.
5962 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5963 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5964 `info' files are also provided. To build `info' files from scratch,
5965 you will need the latest `makeinfo' release, which will be available in
5966 a future texinfo-X.Y release.
5968 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5969 We're not sure exactly which versions have this problem, but it has
5970 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5971 or better. If that isn't possible, there is a patch in
5972 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5973 around this problem.
5977 GDB now supports array constants that can be used in expressions typed in by
5978 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5979 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5982 The new directory `gdb/sparclite' contains a program that demonstrates
5983 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5985 * New native hosts supported
5987 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5988 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5990 * New targets supported
5992 AMD 29k family via UDI a29k-amd-udi or udi29k
5994 * New file formats supported
5996 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5997 HPUX core files, and SCO 3.2v2 core files.
6001 Attaching to processes now works again; thanks for the many bug reports.
6003 We have also stomped on a bunch of core dumps caused by
6004 printf_filtered("%s") problems.
6006 We eliminated a copyright problem on the rpc and ptrace header files
6007 for VxWorks, which was discovered at the last minute during the 4.7
6008 release. You should now be able to build a VxWorks GDB.
6010 You can now interrupt gdb while an attached process is running. This
6011 will cause the attached process to stop, and give control back to GDB.
6013 We fixed problems caused by using too many file descriptors
6014 for reading symbols from object files and libraries. This was
6015 especially a problem for programs that used many (~100) shared
6018 The `step' command now only enters a subroutine if there is line number
6019 information for the subroutine. Otherwise it acts like the `next'
6020 command. Previously, `step' would enter subroutines if there was
6021 any debugging information about the routine. This avoids problems
6022 when using `cc -g1' on MIPS machines.
6024 * Internal improvements
6026 GDB's internal interfaces have been improved to make it easier to support
6027 debugging of multiple languages in the future.
6029 GDB now uses a common structure for symbol information internally.
6030 Minimal symbols (derived from linkage symbols in object files), partial
6031 symbols (from a quick scan of debug information), and full symbols
6032 contain a common subset of information, making it easier to write
6033 shared code that handles any of them.
6035 * New command line options
6037 We now accept --silent as an alias for --quiet.
6041 The memory-mapped-malloc library is now licensed under the GNU Library
6042 General Public License.
6044 *** Changes in GDB-4.7:
6046 * Host/native/target split
6048 GDB has had some major internal surgery to untangle the support for
6049 hosts and remote targets. Now, when you configure GDB for a remote
6050 target, it will no longer load in all of the support for debugging
6051 local programs on the host. When fully completed and tested, this will
6052 ensure that arbitrary host/target combinations are possible.
6054 The primary conceptual shift is to separate the non-portable code in
6055 GDB into three categories. Host specific code is required any time GDB
6056 is compiled on that host, regardless of the target. Target specific
6057 code relates to the peculiarities of the target, but can be compiled on
6058 any host. Native specific code is everything else: it can only be
6059 built when the host and target are the same system. Child process
6060 handling and core file support are two common `native' examples.
6062 GDB's use of /proc for controlling Unix child processes is now cleaner.
6063 It has been split out into a single module under the `target_ops' vector,
6064 plus two native-dependent functions for each system that uses /proc.
6066 * New hosts supported
6068 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6069 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6070 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6072 * New targets supported
6074 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6075 68030 and CPU32 m68030-*-*, m68332-*-*
6077 * New native hosts supported
6079 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6080 (386bsd is not well tested yet)
6081 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6083 * New file formats supported
6085 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6086 supports reading of `a.out.adobe' object files, which are an a.out
6087 format extended with minimal information about multiple sections.
6091 `show copying' is the same as the old `info copying'.
6092 `show warranty' is the same as `info warrantee'.
6093 These were renamed for consistency. The old commands continue to work.
6095 `info handle' is a new alias for `info signals'.
6097 You can now define pre-command hooks, which attach arbitrary command
6098 scripts to any command. The commands in the hook will be executed
6099 prior to the user's command. You can also create a hook which will be
6100 executed whenever the program stops. See gdb.texinfo.
6104 We now deal with Cfront style name mangling, and can even extract type
6105 info from mangled symbols. GDB can automatically figure out which
6106 symbol mangling style your C++ compiler uses.
6108 Calling of methods and virtual functions has been improved as well.
6112 The crash that occured when debugging Sun Ansi-C compiled binaries is
6113 fixed. This was due to mishandling of the extra N_SO stabs output
6116 We also finally got Ultrix 4.2 running in house, and fixed core file
6117 support, with help from a dozen people on the net.
6119 John M. Farrell discovered that the reason that single-stepping was so
6120 slow on all of the Mips based platforms (primarily SGI and DEC) was
6121 that we were trying to demangle and lookup a symbol used for internal
6122 purposes on every instruction that was being stepped through. Changing
6123 the name of that symbol so that it couldn't be mistaken for a C++
6124 mangled symbol sped things up a great deal.
6126 Rich Pixley sped up symbol lookups in general by getting much smarter
6127 about when C++ symbol mangling is necessary. This should make symbol
6128 completion (TAB on the command line) much faster. It's not as fast as
6129 we'd like, but it's significantly faster than gdb-4.6.
6133 A new user controllable variable 'call_scratch_address' can
6134 specify the location of a scratch area to be used when GDB
6135 calls a function in the target. This is necessary because the
6136 usual method of putting the scratch area on the stack does not work
6137 in systems that have separate instruction and data spaces.
6139 We integrated changes to support the 29k UDI (Universal Debugger
6140 Interface), but discovered at the last minute that we didn't have all
6141 of the appropriate copyright paperwork. We are working with AMD to
6142 resolve this, and hope to have it available soon.
6146 We have sped up the remote serial line protocol, especially for targets
6147 with lots of registers. It now supports a new `expedited status' ('T')
6148 message which can be used in place of the existing 'S' status message.
6149 This allows the remote stub to send only the registers that GDB
6150 needs to make a quick decision about single-stepping or conditional
6151 breakpoints, eliminating the need to fetch the entire register set for
6152 each instruction being stepped through.
6154 The GDB remote serial protocol now implements a write-through cache for
6155 registers, only re-reading the registers if the target has run.
6157 There is also a new remote serial stub for SPARC processors. You can
6158 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6159 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6160 processor with a serial port.
6164 Configure.in files have become much easier to read and modify. A new
6165 `table driven' format makes it more obvious what configurations are
6166 supported, and what files each one uses.
6170 There is a new opcodes library which will eventually contain all of the
6171 disassembly routines and opcode tables. At present, it only contains
6172 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6173 disassembler (binutils/objdump) to share these routines.
6175 The libiberty library is now copylefted under the GNU Library General
6176 Public License. This allows more liberal use, and was done so libg++
6177 can use it. This makes no difference to GDB, since the Library License
6178 grants all the rights from the General Public License.
6182 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6183 reference to the stabs symbol info used by the debugger. It is (as far
6184 as we know) the only published document on this fascinating topic. We
6185 encourage you to read it, compare it to the stabs information on your
6186 system, and send improvements on the document in general (to
6187 bug-gdb@prep.ai.mit.edu).
6189 And, of course, many bugs have been fixed.
6192 *** Changes in GDB-4.6:
6194 * Better support for C++ function names
6196 GDB now accepts as input the "demangled form" of C++ overloaded function
6197 names and member function names, and can do command completion on such names
6198 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6199 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6200 Make use of command completion, it is your friend.
6202 GDB also now accepts a variety of C++ mangled symbol formats. They are
6203 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6204 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6205 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6206 for the list of formats.
6208 * G++ symbol mangling problem
6210 Recent versions of gcc have a bug in how they emit debugging information for
6211 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6212 directory) can be applied to gcc to fix the problem. Alternatively, if you
6213 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6214 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6215 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6218 * New 'maintenance' command
6220 All of the commands related to hacking GDB internals have been moved out of
6221 the main command set, and now live behind the 'maintenance' command. This
6222 can also be abbreviated as 'mt'. The following changes were made:
6224 dump-me -> maintenance dump-me
6225 info all-breakpoints -> maintenance info breakpoints
6226 printmsyms -> maintenance print msyms
6227 printobjfiles -> maintenance print objfiles
6228 printpsyms -> maintenance print psymbols
6229 printsyms -> maintenance print symbols
6231 The following commands are new:
6233 maintenance demangle Call internal GDB demangler routine to
6234 demangle a C++ link name and prints the result.
6235 maintenance print type Print a type chain for a given symbol
6237 * Change to .gdbinit file processing
6239 We now read the $HOME/.gdbinit file before processing the argv arguments
6240 (e.g. reading symbol files or core files). This allows global parameters to
6241 be set, which will apply during the symbol reading. The ./.gdbinit is still
6242 read after argv processing.
6244 * New hosts supported
6246 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6248 GNU/Linux support i386-unknown-linux or linux
6250 We are also including code to support the HP/PA running BSD and HPUX. This
6251 is almost guaranteed not to work, as we didn't have time to test or build it
6252 for this release. We are including it so that the more adventurous (or
6253 masochistic) of you can play with it. We also had major problems with the
6254 fact that the compiler that we got from HP doesn't support the -g option.
6257 * New targets supported
6259 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6261 * More smarts about finding #include files
6263 GDB now remembers the compilation directory for all include files, and for
6264 all files from which C is generated (like yacc and lex sources). This
6265 greatly improves GDB's ability to find yacc/lex sources, and include files,
6266 especially if you are debugging your program from a directory different from
6267 the one that contains your sources.
6269 We also fixed a bug which caused difficulty with listing and setting
6270 breakpoints in include files which contain C code. (In the past, you had to
6271 try twice in order to list an include file that you hadn't looked at before.)
6273 * Interesting infernals change
6275 GDB now deals with arbitrary numbers of sections, where the symbols for each
6276 section must be relocated relative to that section's landing place in the
6277 target's address space. This work was needed to support ELF with embedded
6278 stabs used by Solaris-2.0.
6280 * Bug fixes (of course!)
6282 There have been loads of fixes for the following things:
6283 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6284 i960, stabs, DOS(GO32), procfs, etc...
6286 See the ChangeLog for details.
6288 *** Changes in GDB-4.5:
6290 * New machines supported (host and target)
6292 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6294 SGI Irix-4.x mips-sgi-irix4 or iris4
6296 * New malloc package
6298 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6299 Mmalloc is capable of handling mutiple heaps of memory. It is also
6300 capable of saving a heap to a file, and then mapping it back in later.
6301 This can be used to greatly speedup the startup of GDB by using a
6302 pre-parsed symbol table which lives in a mmalloc managed heap. For
6303 more details, please read mmalloc/mmalloc.texi.
6307 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6308 'help info proc' for details.
6310 * MIPS ecoff symbol table format
6312 The code that reads MIPS symbol table format is now supported on all hosts.
6313 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6316 * File name changes for MS-DOS
6318 Many files in the config directories have been renamed to make it easier to
6319 support GDB on MS-DOSe systems (which have very restrictive file name
6320 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6321 environment) is close to working but has some remaining problems. Note
6322 that debugging of DOS programs is not supported, due to limitations
6323 in the ``operating system'', but it can be used to host cross-debugging.
6325 * Cross byte order fixes
6327 Many fixes have been made to support cross debugging of Sparc and MIPS
6328 targets from hosts whose byte order differs.
6330 * New -mapped and -readnow options
6332 If memory-mapped files are available on your system through the 'mmap'
6333 system call, you can use the -mapped option on the `file' or
6334 `symbol-file' commands to cause GDB to write the symbols from your
6335 program into a reusable file. If the program you are debugging is
6336 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6337 Future GDB debugging sessions will notice the presence of this file,
6338 and will quickly map in symbol information from it, rather than reading
6339 the symbol table from the executable program. Using the '-mapped'
6340 option in a GDB `file' or `symbol-file' command has the same effect as
6341 starting GDB with the '-mapped' command-line option.
6343 You can cause GDB to read the entire symbol table immediately by using
6344 the '-readnow' option with any of the commands that load symbol table
6345 information (or on the GDB command line). This makes the command
6346 slower, but makes future operations faster.
6348 The -mapped and -readnow options are typically combined in order to
6349 build a `fred.syms' file that contains complete symbol information.
6350 A simple GDB invocation to do nothing but build a `.syms' file for future
6353 gdb -batch -nx -mapped -readnow programname
6355 The `.syms' file is specific to the host machine on which GDB is run.
6356 It holds an exact image of GDB's internal symbol table. It cannot be
6357 shared across multiple host platforms.
6359 * longjmp() handling
6361 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6362 siglongjmp() without losing control. This feature has not yet been ported to
6363 all systems. It currently works on many 386 platforms, all MIPS-based
6364 platforms (SGI, DECstation, etc), and Sun3/4.
6368 Preliminary work has been put in to support the new Solaris OS from Sun. At
6369 this time, it can control and debug processes, but it is not capable of
6374 As always, many many bug fixes. The major areas were with g++, and mipsread.
6375 People using the MIPS-based platforms should experience fewer mysterious
6376 crashes and trashed symbol tables.
6378 *** Changes in GDB-4.4:
6380 * New machines supported (host and target)
6382 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6384 BSD Reno on Vax vax-dec-bsd
6385 Ultrix on Vax vax-dec-ultrix
6387 * New machines supported (target)
6389 AMD 29000 embedded, using EBMON a29k-none-none
6393 GDB continues to improve its handling of C++. `References' work better.
6394 The demangler has also been improved, and now deals with symbols mangled as
6395 per the Annotated C++ Reference Guide.
6397 GDB also now handles `stabs' symbol information embedded in MIPS
6398 `ecoff' symbol tables. Since the ecoff format was not easily
6399 extensible to handle new languages such as C++, this appeared to be a
6400 good way to put C++ debugging info into MIPS binaries. This option
6401 will be supported in the GNU C compiler, version 2, when it is
6404 * New features for SVR4
6406 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6407 shared libraries. Debugging dynamically linked programs should present
6408 only minor differences from debugging statically linked programs.
6410 The `info proc' command will print out information about any process
6411 on an SVR4 system (including the one you are debugging). At the moment,
6412 it prints the address mappings of the process.
6414 If you bring up GDB on another SVR4 system, please send mail to
6415 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6417 * Better dynamic linking support in SunOS
6419 Reading symbols from shared libraries which contain debugging symbols
6420 now works properly. However, there remain issues such as automatic
6421 skipping of `transfer vector' code during function calls, which
6422 make it harder to debug code in a shared library, than to debug the
6423 same code linked statically.
6427 GDB is now using the latest `getopt' routines from the FSF. This
6428 version accepts the -- prefix for options with long names. GDB will
6429 continue to accept the old forms (-option and +option) as well.
6430 Various single letter abbreviations for options have been explicity
6431 added to the option table so that they won't get overshadowed in the
6432 future by other options that begin with the same letter.
6436 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6437 Many assorted bugs have been handled. Many more remain to be handled.
6438 See the various ChangeLog files (primarily in gdb and bfd) for details.
6441 *** Changes in GDB-4.3:
6443 * New machines supported (host and target)
6445 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6446 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6447 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6449 * Almost SCO Unix support
6451 We had hoped to support:
6452 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6453 (except for core file support), but we discovered very late in the release
6454 that it has problems with process groups that render gdb unusable. Sorry
6455 about that. I encourage people to fix it and post the fixes.
6457 * Preliminary ELF and DWARF support
6459 GDB can read ELF object files on System V Release 4, and can handle
6460 debugging records for C, in DWARF format, in ELF files. This support
6461 is preliminary. If you bring up GDB on another SVR4 system, please
6462 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6467 GDB now uses the latest `readline' library. One user-visible change
6468 is that two tabs will list possible command completions, which previously
6469 required typing M-? (meta-question mark, or ESC ?).
6473 The `stepi' bug that many of you noticed has been squashed.
6474 Many bugs in C++ have been handled. Many more remain to be handled.
6475 See the various ChangeLog files (primarily in gdb and bfd) for details.
6477 * State of the MIPS world (in case you wondered):
6479 GDB can understand the symbol tables emitted by the compilers
6480 supplied by most vendors of MIPS-based machines, including DEC. These
6481 symbol tables are in a format that essentially nobody else uses.
6483 Some versions of gcc come with an assembler post-processor called
6484 mips-tfile. This program is required if you want to do source-level
6485 debugging of gcc-compiled programs. I believe FSF does not ship
6486 mips-tfile with gcc version 1, but it will eventually come with gcc
6489 Debugging of g++ output remains a problem. g++ version 1.xx does not
6490 really support it at all. (If you're lucky, you should be able to get
6491 line numbers and stack traces to work, but no parameters or local
6492 variables.) With some work it should be possible to improve the
6495 When gcc version 2 is released, you will have somewhat better luck.
6496 However, even then you will get confusing results for inheritance and
6499 We will eventually provide full debugging of g++ output on
6500 DECstations. This will probably involve some kind of stabs-in-ecoff
6501 encapulation, but the details have not been worked out yet.
6504 *** Changes in GDB-4.2:
6506 * Improved configuration
6508 Only one copy of `configure' exists now, and it is not self-modifying.
6509 Porting BFD is simpler.
6513 The `step' and `next' commands now only stop at the first instruction
6514 of a source line. This prevents the multiple stops that used to occur
6515 in switch statements, for-loops, etc. `Step' continues to stop if a
6516 function that has debugging information is called within the line.
6520 Lots of small bugs fixed. More remain.
6522 * New host supported (not target)
6524 Intel 386 PC clone running Mach i386-none-mach
6527 *** Changes in GDB-4.1:
6529 * Multiple source language support
6531 GDB now has internal scaffolding to handle several source languages.
6532 It determines the type of each source file from its filename extension,
6533 and will switch expression parsing and number formatting to match the
6534 language of the function in the currently selected stack frame.
6535 You can also specifically set the language to be used, with
6536 `set language c' or `set language modula-2'.
6540 GDB now has preliminary support for the GNU Modula-2 compiler,
6541 currently under development at the State University of New York at
6542 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6543 continue through the fall of 1991 and into 1992.
6545 Other Modula-2 compilers are currently not supported, and attempting to
6546 debug programs compiled with them will likely result in an error as the
6547 symbol table is read. Feel free to work on it, though!
6549 There are hooks in GDB for strict type checking and range checking,
6550 in the `Modula-2 philosophy', but they do not currently work.
6554 GDB can now write to executable and core files (e.g. patch
6555 a variable's value). You must turn this switch on, specify
6556 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6557 by assigning a new value to a variable. Modifications take
6560 * Automatic SunOS shared library reading
6562 When you run your program, GDB automatically determines where its
6563 shared libraries (if any) have been loaded, and reads their symbols.
6564 The `share' command is no longer needed. This also works when
6565 examining core files.
6569 You can specify the number of lines that the `list' command shows.
6572 * New machines supported (host and target)
6574 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6575 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6576 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6578 * New hosts supported (not targets)
6580 IBM RT/PC: romp-ibm-aix or rtpc
6582 * New targets supported (not hosts)
6584 AMD 29000 embedded with COFF a29k-none-coff
6585 AMD 29000 embedded with a.out a29k-none-aout
6586 Ultracomputer remote kernel debug a29k-nyu-kern
6588 * New remote interfaces
6594 *** Changes in GDB-4.0:
6598 Wide output is wrapped at good places to make the output more readable.
6600 Gdb now supports cross-debugging from a host machine of one type to a
6601 target machine of another type. Communication with the target system
6602 is over serial lines. The ``target'' command handles connecting to the
6603 remote system; the ``load'' command will download a program into the
6604 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6605 also supports debugging of realtime processes running under VxWorks,
6606 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6607 stub on the target system.
6609 New CPUs supported include the AMD 29000 and Intel 960.
6611 GDB now reads object files and symbol tables via a ``binary file''
6612 library, which allows a single copy of GDB to debug programs of multiple
6613 object file types such as a.out and coff.
6615 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6616 refcard.dvi and refcard.ps are available to format it).
6619 * Control-Variable user interface simplified
6621 All variables that control the operation of the debugger can be set
6622 by the ``set'' command, and displayed by the ``show'' command.
6624 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6625 ``Show prompt'' produces the response:
6626 Gdb's prompt is new-gdb=>.
6628 What follows are the NEW set commands. The command ``help set'' will
6629 print a complete list of old and new set commands. ``help set FOO''
6630 will give a longer description of the variable FOO. ``show'' will show
6631 all of the variable descriptions and their current settings.
6633 confirm on/off: Enables warning questions for operations that are
6634 hard to recover from, e.g. rerunning the program while
6635 it is already running. Default is ON.
6637 editing on/off: Enables EMACS style command line editing
6638 of input. Previous lines can be recalled with
6639 control-P, the current line can be edited with control-B,
6640 you can search for commands with control-R, etc.
6643 history filename NAME: NAME is where the gdb command history
6644 will be stored. The default is .gdb_history,
6645 or the value of the environment variable
6648 history size N: The size, in commands, of the command history. The
6649 default is 256, or the value of the environment variable
6652 history save on/off: If this value is set to ON, the history file will
6653 be saved after exiting gdb. If set to OFF, the
6654 file will not be saved. The default is OFF.
6656 history expansion on/off: If this value is set to ON, then csh-like
6657 history expansion will be performed on
6658 command line input. The default is OFF.
6660 radix N: Sets the default radix for input and output. It can be set
6661 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6662 in the current radix, so "set radix 10" is always a no-op.
6664 height N: This integer value is the number of lines on a page. Default
6665 is 24, the current `stty rows'' setting, or the ``li#''
6666 setting from the termcap entry matching the environment
6669 width N: This integer value is the number of characters on a line.
6670 Default is 80, the current `stty cols'' setting, or the ``co#''
6671 setting from the termcap entry matching the environment
6674 Note: ``set screensize'' is obsolete. Use ``set height'' and
6675 ``set width'' instead.
6677 print address on/off: Print memory addresses in various command displays,
6678 such as stack traces and structure values. Gdb looks
6679 more ``symbolic'' if you turn this off; it looks more
6680 ``machine level'' with it on. Default is ON.
6682 print array on/off: Prettyprint arrays. New convenient format! Default
6685 print demangle on/off: Print C++ symbols in "source" form if on,
6688 print asm-demangle on/off: Same, for assembler level printouts
6691 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6694 * Support for Epoch Environment.
6696 The epoch environment is a version of Emacs v18 with windowing. One
6697 new command, ``inspect'', is identical to ``print'', except that if you
6698 are running in the epoch environment, the value is printed in its own
6702 * Support for Shared Libraries
6704 GDB can now debug programs and core files that use SunOS shared libraries.
6705 Symbols from a shared library cannot be referenced
6706 before the shared library has been linked with the program (this
6707 happens after you type ``run'' and before the function main() is entered).
6708 At any time after this linking (including when examining core files
6709 from dynamically linked programs), gdb reads the symbols from each
6710 shared library when you type the ``sharedlibrary'' command.
6711 It can be abbreviated ``share''.
6713 sharedlibrary REGEXP: Load shared object library symbols for files
6714 matching a unix regular expression. No argument
6715 indicates to load symbols for all shared libraries.
6717 info sharedlibrary: Status of loaded shared libraries.
6722 A watchpoint stops execution of a program whenever the value of an
6723 expression changes. Checking for this slows down execution
6724 tremendously whenever you are in the scope of the expression, but is
6725 quite useful for catching tough ``bit-spreader'' or pointer misuse
6726 problems. Some machines such as the 386 have hardware for doing this
6727 more quickly, and future versions of gdb will use this hardware.
6729 watch EXP: Set a watchpoint (breakpoint) for an expression.
6731 info watchpoints: Information about your watchpoints.
6733 delete N: Deletes watchpoint number N (same as breakpoints).
6734 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6735 enable N: Re-enables watchpoint number N (same as breakpoints).
6738 * C++ multiple inheritance
6740 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6743 * C++ exception handling
6745 Gdb now supports limited C++ exception handling. Besides the existing
6746 ability to breakpoint on an exception handler, gdb can breakpoint on
6747 the raising of an exception (before the stack is peeled back to the
6750 catch FOO: If there is a FOO exception handler in the dynamic scope,
6751 set a breakpoint to catch exceptions which may be raised there.
6752 Multiple exceptions (``catch foo bar baz'') may be caught.
6754 info catch: Lists all exceptions which may be caught in the
6755 current stack frame.
6758 * Minor command changes
6760 The command ``call func (arg, arg, ...)'' now acts like the print
6761 command, except it does not print or save a value if the function's result
6762 is void. This is similar to dbx usage.
6764 The ``up'' and ``down'' commands now always print the frame they end up
6765 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6766 frames without printing.
6768 * New directory command
6770 'dir' now adds directories to the FRONT of the source search path.
6771 The path starts off empty. Source files that contain debug information
6772 about the directory in which they were compiled can be found even
6773 with an empty path; Sun CC and GCC include this information. If GDB can't
6774 find your source file in the current directory, type "dir .".
6776 * Configuring GDB for compilation
6778 For normal use, type ``./configure host''. See README or gdb.texinfo
6781 GDB now handles cross debugging. If you are remotely debugging between
6782 two different machines, type ``./configure host -target=targ''.
6783 Host is the machine where GDB will run; targ is the machine
6784 where the program that you are debugging will run.