1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 8.1
6 * The endianness used with the 'set endian auto' mode in the absence of
7 an executable selected for debugging is now the last endianness chosen
8 either by one of the 'set endian big' and 'set endian little' commands
9 or by inferring from the last executable used, rather than the startup
12 * The commands 'info variables/functions/types' now show the source line
13 numbers of symbol definitions when available.
15 * 'info proc' now works on running processes on FreeBSD systems and core
16 files created on FreeBSD systems.
18 * C expressions can now use _Alignof, and C++ expressions can now use
25 Control display of debugging info regarding the FreeBSD native target.
27 set|show varsize-limit
28 This new setting allows the user to control the maximum size of Ada
29 objects being printed when those objects have a variable type,
30 instead of that maximum size being hardcoded to 65536 bytes.
32 set|show record btrace cpu
33 Controls the processor to be used for enabling errata workarounds for
38 ** Type alignment is now exposed via the "align" attribute of a gdb.Type.
40 ** The commands attached to a breakpoint can be set by assigning to
41 the breakpoint's "commands" field.
43 ** gdb.execute can now execute multi-line gdb commands.
45 ** The new functions gdb.convenience_variable and
46 gdb.set_convenience_variable can be used to get and set the value
47 of convenience variables.
51 RiscV ELF riscv*-*-elf
53 * Removed targets and native configurations
55 m88k running OpenBSD m88*-*-openbsd*
56 SH-5/SH64 ELF sh64-*-elf*, SH-5/SH64 support in sh*
57 SH-5/SH64 running GNU/Linux SH-5/SH64 support in sh*-*-linux*
58 SH-5/SH64 running OpenBSD SH-5/SH64 support in sh*-*-openbsd*
60 * Aarch64/Linux hardware watchpoints improvements
62 Hardware watchpoints on unaligned addresses are now properly
63 supported when running Linux kernel 4.10 or higher: read and access
64 watchpoints are no longer spuriously missed, and all watchpoints
65 lengths between 1 and 8 bytes are supported. On older kernels,
66 watchpoints set on unaligned addresses are no longer missed, with
67 the tradeoff that there is a possibility of false hits being
70 *** Changes in GDB 8.1
72 * GDB now supports dynamically creating arbitrary register groups specified
73 in XML target descriptions. This allows for finer grain grouping of
74 registers on systems with a large amount of registers.
76 * The 'ptype' command now accepts a '/o' flag, which prints the
77 offsets and sizes of fields in a struct, like the pahole(1) tool.
79 * New "--readnever" command line option instructs GDB to not read each
80 symbol file's symbolic debug information. This makes startup faster
81 but at the expense of not being able to perform symbolic debugging.
82 This option is intended for use cases where symbolic debugging will
83 not be used, e.g., when you only need to dump the debuggee's core.
85 * GDB now uses the GNU MPFR library, if available, to emulate target
86 floating-point arithmetic during expression evaluation when the target
87 uses different floating-point formats than the host. At least version
88 3.1 of GNU MPFR is required.
90 * GDB now supports access to the guarded-storage-control registers and the
91 software-based guarded-storage broadcast control registers on IBM z14.
93 * On Unix systems, GDB now supports transmitting environment variables
94 that are to be set or unset to GDBserver. These variables will
95 affect the environment to be passed to the remote inferior.
97 To inform GDB of environment variables that are to be transmitted to
98 GDBserver, use the "set environment" command. Only user set
99 environment variables are sent to GDBserver.
101 To inform GDB of environment variables that are to be unset before
102 the remote inferior is started by the GDBserver, use the "unset
103 environment" command.
105 * Completion improvements
107 ** GDB can now complete function parameters in linespecs and
108 explicit locations without quoting. When setting breakpoints,
109 quoting around functions names to help with TAB-completion is
110 generally no longer necessary. For example, this now completes
113 (gdb) b function(in[TAB]
114 (gdb) b function(int)
116 Related, GDB is no longer confused with completing functions in
117 C++ anonymous namespaces:
120 (gdb) b (anonymous namespace)::[TAB][TAB]
121 (anonymous namespace)::a_function()
122 (anonymous namespace)::b_function()
124 ** GDB now has much improved linespec and explicit locations TAB
125 completion support, that better understands what you're
126 completing and offers better suggestions. For example, GDB no
127 longer offers data symbols as possible completions when you're
128 setting a breakpoint.
130 ** GDB now TAB-completes label symbol names.
132 ** The "complete" command now mimics TAB completion accurately.
134 * New command line options (gcore)
137 Dump all memory mappings.
139 * Breakpoints on C++ functions are now set on all scopes by default
141 By default, breakpoints on functions/methods are now interpreted as
142 specifying all functions with the given name ignoring missing
143 leading scopes (namespaces and classes).
145 For example, assuming a C++ program with symbols named:
150 both commands "break func()" and "break B::func()" set a breakpoint
153 You can use the new flag "-qualified" to override this. This makes
154 GDB interpret the specified function name as a complete
155 fully-qualified name instead. For example, using the same C++
156 program, the "break -q B::func" command sets a breakpoint on
157 "B::func", only. A parameter has been added to the Python
158 gdb.Breakpoint constructor to achieve the same result when creating
159 a breakpoint from Python.
161 * Breakpoints on functions marked with C++ ABI tags
163 GDB can now set breakpoints on functions marked with C++ ABI tags
164 (e.g., [abi:cxx11]). See here for a description of ABI tags:
165 https://developers.redhat.com/blog/2015/02/05/gcc5-and-the-c11-abi/
167 Functions with a C++11 abi tag are demangled/displayed like this:
169 function[abi:cxx11](int)
172 You can now set a breakpoint on such functions simply as if they had
175 (gdb) b function(int)
177 Or if you need to disambiguate between tags, like:
179 (gdb) b function[abi:other_tag](int)
181 Tab completion was adjusted accordingly as well.
185 ** New events gdb.new_inferior, gdb.inferior_deleted, and
186 gdb.new_thread are emitted. See the manual for further
187 description of these.
189 ** A new function, "gdb.rbreak" has been added to the Python API.
190 This function allows the setting of a large number of breakpoints
191 via a regex pattern in Python. See the manual for further details.
193 ** Python breakpoints can now accept explicit locations. See the
194 manual for a further description of this feature.
197 * New features in the GDB remote stub, GDBserver
199 ** GDBserver is now able to start inferior processes with a
200 specified initial working directory.
202 The user can set the desired working directory to be used from
203 GDB using the new "set cwd" command.
205 ** New "--selftest" command line option runs some GDBserver self
206 tests. These self tests are disabled in releases.
208 ** On Unix systems, GDBserver now does globbing expansion and variable
209 substitution in inferior command line arguments.
211 This is done by starting inferiors using a shell, like GDB does.
212 See "set startup-with-shell" in the user manual for how to disable
213 this from GDB when using "target extended-remote". When using
214 "target remote", you can disable the startup with shell by using the
215 new "--no-startup-with-shell" GDBserver command line option.
217 ** On Unix systems, GDBserver now supports receiving environment
218 variables that are to be set or unset from GDB. These variables
219 will affect the environment to be passed to the inferior.
221 * When catching an Ada exception raised with a message, GDB now prints
222 the message in the catchpoint hit notification. In GDB/MI mode, that
223 information is provided as an extra field named "exception-message"
224 in the *stopped notification.
226 * Trait objects can now be inspected When debugging Rust code. This
227 requires compiler support which will appear in Rust 1.24.
231 QEnvironmentHexEncoded
232 Inform GDBserver of an environment variable that is to be passed to
233 the inferior when starting it.
236 Inform GDBserver of an environment variable that is to be unset
237 before starting the remote inferior.
240 Inform GDBserver that the environment should be reset (i.e.,
241 user-set environment variables should be unset).
244 Indicates whether the inferior must be started with a shell or not.
247 Tell GDBserver that the inferior to be started should use a specific
250 * The "maintenance print c-tdesc" command now takes an optional
251 argument which is the file name of XML target description.
253 * The "maintenance selftest" command now takes an optional argument to
254 filter the tests to be run.
256 * The "enable", and "disable" commands now accept a range of
257 breakpoint locations, e.g. "enable 1.3-5".
262 Set and show the current working directory for the inferior.
265 Set and show compilation command used for compiling and injecting code
266 with the 'compile' commands.
268 set debug separate-debug-file
269 show debug separate-debug-file
270 Control the display of debug output about separate debug file search.
272 set dump-excluded-mappings
273 show dump-excluded-mappings
274 Control whether mappings marked with the VM_DONTDUMP flag should be
275 dumped when generating a core file.
278 List the registered selftests.
281 Start the debugged program stopping at the first instruction.
284 Control display of debugging messages related to OpenRISC targets.
286 set|show print type nested-type-limit
287 Set and show the limit of nesting level for nested types that the
288 type printer will show.
290 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
293 * Safer/improved support for debugging with no debug info
295 GDB no longer assumes functions with no debug information return
298 This means that GDB now refuses to call such functions unless you
299 tell it the function's type, by either casting the call to the
300 declared return type, or by casting the function to a function
301 pointer of the right type, and calling that:
303 (gdb) p getenv ("PATH")
304 'getenv' has unknown return type; cast the call to its declared return type
305 (gdb) p (char *) getenv ("PATH")
306 $1 = 0x7fffffffe "/usr/local/bin:/"...
307 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
308 $2 = 0x7fffffffe "/usr/local/bin:/"...
310 Similarly, GDB no longer assumes that global variables with no debug
311 info have type 'int', and refuses to print the variable's value
312 unless you tell it the variable's type:
315 'var' has unknown type; cast it to its declared type
319 * New native configurations
321 FreeBSD/aarch64 aarch64*-*-freebsd*
322 FreeBSD/arm arm*-*-freebsd*
326 FreeBSD/aarch64 aarch64*-*-freebsd*
327 FreeBSD/arm arm*-*-freebsd*
328 OpenRISC ELF or1k*-*-elf
330 * Removed targets and native configurations
332 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
334 *** Changes in GDB 8.0
336 * GDB now supports access to the PKU register on GNU/Linux. The register is
337 added by the Memory Protection Keys for Userspace feature which will be
338 available in future Intel CPUs.
340 * GDB now supports C++11 rvalue references.
344 ** New functions to start, stop and access a running btrace recording.
345 ** Rvalue references are now supported in gdb.Type.
347 * GDB now supports recording and replaying rdrand and rdseed Intel 64
350 * Building GDB and GDBserver now requires a C++11 compiler.
352 For example, GCC 4.8 or later.
354 It is no longer possible to build GDB or GDBserver with a C
355 compiler. The --disable-build-with-cxx configure option has been
358 * Building GDB and GDBserver now requires GNU make >= 3.81.
360 It is no longer supported to build GDB or GDBserver with another
361 implementation of the make program or an earlier version of GNU make.
363 * Native debugging on MS-Windows supports command-line redirection
365 Command-line arguments used for starting programs on MS-Windows can
366 now include redirection symbols supported by native Windows shells,
367 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
368 as "run", "start", and "set args", as well as the corresponding MI
371 * Support for thread names on MS-Windows.
373 GDB now catches and handles the special exception that programs
374 running on MS-Windows use to assign names to threads in the
377 * Support for Java programs compiled with gcj has been removed.
379 * User commands now accept an unlimited number of arguments.
380 Previously, only up to 10 was accepted.
382 * The "eval" command now expands user-defined command arguments.
384 This makes it easier to process a variable number of arguments:
389 eval "print $arg%d", $i
394 * Target descriptions can now describe registers for sparc32 and sparc64.
396 * GDB now supports DWARF version 5 (debug information format).
397 Its .debug_names index is not yet supported.
399 * New native configurations
401 FreeBSD/mips mips*-*-freebsd
405 Synopsys ARC arc*-*-elf32
406 FreeBSD/mips mips*-*-freebsd
408 * Removed targets and native configurations
410 Alpha running FreeBSD alpha*-*-freebsd*
411 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
416 Erases all the flash memory regions reported by the target.
418 maint print arc arc-instruction address
419 Print internal disassembler information about instruction at a given address.
423 set disassembler-options
424 show disassembler-options
425 Controls the passing of target specific information to the disassembler.
426 If it is necessary to specify more than one disassembler option then
427 multiple options can be placed together into a comma separated list.
428 The default value is the empty string. Currently, the only supported
429 targets are ARM, PowerPC and S/390.
434 Erases all the flash memory regions reported by the target. This is
435 equivalent to the CLI command flash-erase.
437 -file-list-shared-libraries
438 List the shared libraries in the program. This is
439 equivalent to the CLI command "info shared".
442 Catchpoints stopping the program when Ada exceptions are
443 handled. This is equivalent to the CLI command "catch handlers".
445 *** Changes in GDB 7.12
447 * GDB and GDBserver now build with a C++ compiler by default.
449 The --enable-build-with-cxx configure option is now enabled by
450 default. One must now explicitly configure with
451 --disable-build-with-cxx in order to build with a C compiler. This
452 option will be removed in a future release.
454 * GDBserver now supports recording btrace without maintaining an active
457 * GDB now supports a negative repeat count in the 'x' command to examine
458 memory backward from the given address. For example:
461 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
462 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
463 (gdb) x/-5i 0x0000000000400580
464 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
465 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
466 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
467 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
468 0x40057b <main(int, char**)+25>:
469 callq 0x400536 <Func1(int, char const*)>
471 * Fortran: Support structures with fields of dynamic types and
472 arrays of dynamic types.
474 * The symbol dumping maintenance commands have new syntax.
475 maint print symbols [-pc address] [--] [filename]
476 maint print symbols [-objfile objfile] [-source source] [--] [filename]
477 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
478 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
479 maint print msymbols [-objfile objfile] [--] [filename]
481 * GDB now supports multibit bitfields and enums in target register
484 * New Python-based convenience function $_as_string(val), which returns
485 the textual representation of a value. This function is especially
486 useful to obtain the text label of an enum value.
488 * Intel MPX bound violation handling.
490 Segmentation faults caused by a Intel MPX boundary violation
491 now display the kind of violation (upper or lower), the memory
492 address accessed and the memory bounds, along with the usual
493 signal received and code location.
497 Program received signal SIGSEGV, Segmentation fault
498 Upper bound violation while accessing address 0x7fffffffc3b3
499 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
500 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
502 * Rust language support.
503 GDB now supports debugging programs written in the Rust programming
504 language. See https://www.rust-lang.org/ for more information about
507 * Support for running interpreters on specified input/output devices
509 GDB now supports a new mechanism that allows frontends to provide
510 fully featured GDB console views, as a better alternative to
511 building such views on top of the "-interpreter-exec console"
512 command. See the new "new-ui" command below. With that command,
513 frontends can now start GDB in the traditional command-line mode
514 running in an embedded terminal emulator widget, and create a
515 separate MI interpreter running on a specified i/o device. In this
516 way, GDB handles line editing, history, tab completion, etc. in the
517 console all by itself, and the GUI uses the separate MI interpreter
518 for its own control and synchronization, invisible to the command
521 * The "catch syscall" command catches groups of related syscalls.
523 The "catch syscall" command now supports catching a group of related
524 syscalls using the 'group:' or 'g:' prefix.
529 skip -gfile file-glob-pattern
530 skip -function function
531 skip -rfunction regular-expression
532 A generalized form of the skip command, with new support for
533 glob-style file names and regular expressions for function names.
534 Additionally, a file spec and a function spec may now be combined.
536 maint info line-table REGEXP
537 Display the contents of GDB's internal line table data struture.
540 Run any GDB unit tests that were compiled in.
543 Start a new user interface instance running INTERP as interpreter,
544 using the TTY file for input/output.
548 ** gdb.Breakpoint objects have a new attribute "pending", which
549 indicates whether the breakpoint is pending.
550 ** Three new breakpoint-related events have been added:
551 gdb.breakpoint_created, gdb.breakpoint_modified, and
552 gdb.breakpoint_deleted.
555 Signal ("set") the given MS-Windows event object. This is used in
556 conjunction with the Windows JIT debugging (AeDebug) support, where
557 the OS suspends a crashing process until a debugger can attach to
558 it. Resuming the crashing process, in order to debug it, is done by
561 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
562 was added in GDBserver, including JIT compiling fast tracepoint's
563 conditional expression bytecode into native code.
565 * Support for various remote target protocols and ROM monitors has
568 target m32rsdi Remote M32R debugging over SDI
569 target mips MIPS remote debugging protocol
570 target pmon PMON ROM monitor
571 target ddb NEC's DDB variant of PMON for Vr4300
572 target rockhopper NEC RockHopper variant of PMON
573 target lsi LSI variant of PMO
575 * Support for tracepoints and fast tracepoints on powerpc-linux,
576 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
577 including JIT compiling fast tracepoint's conditional expression
578 bytecode into native code.
580 * MI async record =record-started now includes the method and format used for
581 recording. For example:
583 =record-started,thread-group="i1",method="btrace",format="bts"
585 * MI async record =thread-selected now includes the frame field. For example:
587 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
591 Andes NDS32 nds32*-*-elf
593 *** Changes in GDB 7.11
595 * GDB now supports debugging kernel-based threads on FreeBSD.
597 * Per-inferior thread numbers
599 Thread numbers are now per inferior instead of global. If you're
600 debugging multiple inferiors, GDB displays thread IDs using a
601 qualified INF_NUM.THR_NUM form. For example:
605 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
606 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
607 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
608 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
610 As consequence, thread numbers as visible in the $_thread
611 convenience variable and in Python's InferiorThread.num attribute
612 are no longer unique between inferiors.
614 GDB now maintains a second thread ID per thread, referred to as the
615 global thread ID, which is the new equivalent of thread numbers in
616 previous releases. See also $_gthread below.
618 For backwards compatibility, MI's thread IDs always refer to global
621 * Commands that accept thread IDs now accept the qualified
622 INF_NUM.THR_NUM form as well. For example:
625 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
628 * In commands that accept a list of thread IDs, you can now refer to
629 all threads of an inferior using a star wildcard. GDB accepts
630 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
631 refer to all threads of the current inferior. For example, "info
634 * You can use "info threads -gid" to display the global thread ID of
637 * The new convenience variable $_gthread holds the global number of
640 * The new convenience variable $_inferior holds the number of the
643 * GDB now displays the ID and name of the thread that hit a breakpoint
644 or received a signal, if your program is multi-threaded. For
647 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
648 Thread 1 "main" received signal SIGINT, Interrupt.
650 * Record btrace now supports non-stop mode.
652 * Support for tracepoints on aarch64-linux was added in GDBserver.
654 * The 'record instruction-history' command now indicates speculative execution
655 when using the Intel Processor Trace recording format.
657 * GDB now allows users to specify explicit locations, bypassing
658 the linespec parser. This feature is also available to GDB/MI
661 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
662 GDB now is able to debug both AArch64 applications and ARM applications
665 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
666 including JIT compiling fast tracepoint's conditional expression bytecode
669 * GDB now supports displaced stepping on AArch64 GNU/Linux.
671 * "info threads", "info inferiors", "info display", "info checkpoints"
672 and "maint info program-spaces" now list the corresponding items in
673 ascending ID order, for consistency with all other "info" commands.
675 * In Ada, the overloads selection menu has been enhanced to display the
676 parameter types and the return types for the matching overloaded subprograms.
680 maint set target-non-stop (on|off|auto)
681 maint show target-non-stop
682 Control whether GDB targets always operate in non-stop mode even if
683 "set non-stop" is "off". The default is "auto", meaning non-stop
684 mode is enabled if supported by the target.
686 maint set bfd-sharing
687 maint show bfd-sharing
688 Control the reuse of bfd objects.
692 Control display of debugging info regarding bfd caching.
696 Control display of debugging info regarding FreeBSD threads.
698 set remote multiprocess-extensions-packet
699 show remote multiprocess-extensions-packet
700 Set/show the use of the remote protocol multiprocess extensions.
702 set remote thread-events
703 show remote thread-events
704 Set/show the use of thread create/exit events.
706 set ada print-signatures on|off
707 show ada print-signatures"
708 Control whether parameter types and return types are displayed in overloads
709 selection menus. It is activaled (@code{on}) by default.
713 Controls the maximum size of memory, in bytes, that GDB will
714 allocate for value contents. Prevents incorrect programs from
715 causing GDB to allocate overly large buffers. Default is 64k.
717 * The "disassemble" command accepts a new modifier: /s.
718 It prints mixed source+disassembly like /m with two differences:
719 - disassembled instructions are now printed in program order, and
720 - and source for all relevant files is now printed.
721 The "/m" option is now considered deprecated: its "source-centric"
722 output hasn't proved useful in practice.
724 * The "record instruction-history" command accepts a new modifier: /s.
725 It behaves exactly like /m and prints mixed source+disassembly.
727 * The "set scheduler-locking" command supports a new mode "replay".
728 It behaves like "off" in record mode and like "on" in replay mode.
730 * Support for various ROM monitors has been removed:
732 target dbug dBUG ROM monitor for Motorola ColdFire
733 target picobug Motorola picobug monitor
734 target dink32 DINK32 ROM monitor for PowerPC
735 target m32r Renesas M32R/D ROM monitor
736 target mon2000 mon2000 ROM monitor
737 target ppcbug PPCBUG ROM monitor for PowerPC
739 * Support for reading/writing memory and extracting values on architectures
740 whose memory is addressable in units of any integral multiple of 8 bits.
743 Allows to break when an Ada exception is handled.
748 Indicates that an exec system call was executed.
750 exec-events feature in qSupported
751 The qSupported packet allows GDB to request support for exec
752 events using the new 'gdbfeature' exec-event, and the qSupported
753 response can contain the corresponding 'stubfeature'. Set and
754 show commands can be used to display whether these features are enabled.
757 Equivalent to interrupting with the ^C character, but works in
760 thread created stop reason (T05 create:...)
761 Indicates that the thread was just created and is stopped at entry.
763 thread exit stop reply (w exitcode;tid)
764 Indicates that the thread has terminated.
767 Enables/disables thread create and exit event reporting. For
768 example, this is used in non-stop mode when GDB stops a set of
769 threads and synchronously waits for the their corresponding stop
770 replies. Without exit events, if one of the threads exits, GDB
771 would hang forever not knowing that it should no longer expect a
772 stop for that same thread.
775 Indicates that there are no resumed threads left in the target (all
776 threads are stopped). The remote stub reports support for this stop
777 reply to GDB's qSupported query.
780 Enables/disables catching syscalls from the inferior process.
781 The remote stub reports support for this packet to GDB's qSupported query.
783 syscall_entry stop reason
784 Indicates that a syscall was just called.
786 syscall_return stop reason
787 Indicates that a syscall just returned.
789 * Extended-remote exec events
791 ** GDB now has support for exec events on extended-remote Linux targets.
792 For such targets with Linux kernels 2.5.46 and later, this enables
793 follow-exec-mode and exec catchpoints.
795 set remote exec-event-feature-packet
796 show remote exec-event-feature-packet
797 Set/show the use of the remote exec event feature.
799 * Thread names in remote protocol
801 The reply to qXfer:threads:read may now include a name attribute for each
804 * Target remote mode fork and exec events
806 ** GDB now has support for fork and exec events on target remote mode
807 Linux targets. For such targets with Linux kernels 2.5.46 and later,
808 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
809 fork and exec catchpoints.
811 * Remote syscall events
813 ** GDB now has support for catch syscall on remote Linux targets,
814 currently enabled on x86/x86_64 architectures.
816 set remote catch-syscall-packet
817 show remote catch-syscall-packet
818 Set/show the use of the remote catch syscall feature.
822 ** The -var-set-format command now accepts the zero-hexadecimal
823 format. It outputs data in hexadecimal format with zero-padding on the
828 ** gdb.InferiorThread objects have a new attribute "global_num",
829 which refers to the thread's global thread ID. The existing
830 "num" attribute now refers to the thread's per-inferior number.
831 See "Per-inferior thread numbers" above.
832 ** gdb.InferiorThread objects have a new attribute "inferior", which
833 is the Inferior object the thread belongs to.
835 *** Changes in GDB 7.10
837 * Support for process record-replay and reverse debugging on aarch64*-linux*
838 targets has been added. GDB now supports recording of A64 instruction set
839 including advance SIMD instructions.
841 * Support for Sun's version of the "stabs" debug file format has been removed.
843 * GDB now honors the content of the file /proc/PID/coredump_filter
844 (PID is the process ID) on GNU/Linux systems. This file can be used
845 to specify the types of memory mappings that will be included in a
846 corefile. For more information, please refer to the manual page of
847 "core(5)". GDB also has a new command: "set use-coredump-filter
848 on|off". It allows to set whether GDB will read the content of the
849 /proc/PID/coredump_filter file when generating a corefile.
851 * The "info os" command on GNU/Linux can now display information on
853 "info os cpus" Listing of all cpus/cores on the system
855 * GDB has two new commands: "set serial parity odd|even|none" and
856 "show serial parity". These allows to set or show parity for the
859 * The "info source" command now displays the producer string if it was
860 present in the debug info. This typically includes the compiler version
861 and may include things like its command line arguments.
863 * The "info dll", an alias of the "info sharedlibrary" command,
864 is now available on all platforms.
866 * Directory names supplied to the "set sysroot" commands may be
867 prefixed with "target:" to tell GDB to access shared libraries from
868 the target system, be it local or remote. This replaces the prefix
869 "remote:". The default sysroot has been changed from "" to
870 "target:". "remote:" is automatically converted to "target:" for
871 backward compatibility.
873 * The system root specified by "set sysroot" will be prepended to the
874 filename of the main executable (if reported to GDB as absolute by
875 the operating system) when starting processes remotely, and when
876 attaching to already-running local or remote processes.
878 * GDB now supports automatic location and retrieval of executable
879 files from remote targets. Remote debugging can now be initiated
880 using only a "target remote" or "target extended-remote" command
881 (no "set sysroot" or "file" commands are required). See "New remote
884 * The "dump" command now supports verilog hex format.
886 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
888 * On GNU/Linux, GDB and gdbserver are now able to access executable
889 and shared library files without a "set sysroot" command when
890 attaching to processes running in different mount namespaces from
891 the debugger. This makes it possible to attach to processes in
892 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
893 See "New remote packets" below.
895 * The "tui reg" command now provides completion for all of the
896 available register groups, including target specific groups.
898 * The HISTSIZE environment variable is no longer read when determining
899 the size of GDB's command history. GDB now instead reads the dedicated
900 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
901 disables truncation of command history. Non-numeric values of GDBHISTSIZE
906 ** Memory ports can now be unbuffered.
910 ** gdb.Objfile objects have a new attribute "username",
911 which is the name of the objfile as specified by the user,
912 without, for example, resolving symlinks.
913 ** You can now write frame unwinders in Python.
914 ** gdb.Type objects have a new method "optimized_out",
915 returning optimized out gdb.Value instance of this type.
916 ** gdb.Value objects have new methods "reference_value" and
917 "const_value" which return a reference to the value and a
918 "const" version of the value respectively.
922 maint print symbol-cache
923 Print the contents of the symbol cache.
925 maint print symbol-cache-statistics
926 Print statistics of symbol cache usage.
928 maint flush-symbol-cache
929 Flush the contents of the symbol cache.
933 Start branch trace recording using Branch Trace Store (BTS) format.
936 Evaluate expression by using the compiler and print result.
940 Explicit commands for enabling and disabling tui mode.
943 set mpx bound on i386 and amd64
944 Support for bound table investigation on Intel MPX enabled applications.
948 Start branch trace recording using Intel Processor Trace format.
951 Print information about branch tracing internals.
953 maint btrace packet-history
954 Print the raw branch tracing data.
956 maint btrace clear-packet-history
957 Discard the stored raw branch tracing data.
960 Discard all branch tracing data. It will be fetched and processed
961 anew by the next "record" command.
966 Renamed from "set debug dwarf2-die".
968 Renamed from "show debug dwarf2-die".
971 Renamed from "set debug dwarf2-read".
972 show debug dwarf-read
973 Renamed from "show debug dwarf2-read".
975 maint set dwarf always-disassemble
976 Renamed from "maint set dwarf2 always-disassemble".
977 maint show dwarf always-disassemble
978 Renamed from "maint show dwarf2 always-disassemble".
980 maint set dwarf max-cache-age
981 Renamed from "maint set dwarf2 max-cache-age".
982 maint show dwarf max-cache-age
983 Renamed from "maint show dwarf2 max-cache-age".
986 show debug dwarf-line
987 Control display of debugging info regarding DWARF line processing.
991 Set the maximum number of candidates to be considered during
992 completion. The default value is 200. This limit allows GDB
993 to avoid generating large completion lists, the computation of
994 which can cause the debugger to become temporarily unresponsive.
996 set history remove-duplicates
997 show history remove-duplicates
998 Control the removal of duplicate history entries.
1000 maint set symbol-cache-size
1001 maint show symbol-cache-size
1002 Control the size of the symbol cache.
1004 set|show record btrace bts buffer-size
1005 Set and show the size of the ring buffer used for branch tracing in
1007 The obtained size may differ from the requested size. Use "info
1008 record" to see the obtained buffer size.
1010 set debug linux-namespaces
1011 show debug linux-namespaces
1012 Control display of debugging info regarding Linux namespaces.
1014 set|show record btrace pt buffer-size
1015 Set and show the size of the ring buffer used for branch tracing in
1016 Intel Processor Trace format.
1017 The obtained size may differ from the requested size. Use "info
1018 record" to see the obtained buffer size.
1020 maint set|show btrace pt skip-pad
1021 Set and show whether PAD packets are skipped when computing the
1024 * The command 'thread apply all' can now support new option '-ascending'
1025 to call its specified command for all threads in ascending order.
1027 * Python/Guile scripting
1029 ** GDB now supports auto-loading of Python/Guile scripts contained in the
1030 special section named `.debug_gdb_scripts'.
1032 * New remote packets
1034 qXfer:btrace-conf:read
1035 Return the branch trace configuration for the current thread.
1037 Qbtrace-conf:bts:size
1038 Set the requested ring buffer size for branch tracing in BTS format.
1041 Enable Intel Procesor Trace-based branch tracing for the current
1042 process. The remote stub reports support for this packet to GDB's
1045 Qbtrace-conf:pt:size
1046 Set the requested ring buffer size for branch tracing in Intel Processor
1050 Indicates a memory breakpoint instruction was executed, irrespective
1051 of whether it was GDB that planted the breakpoint or the breakpoint
1052 is hardcoded in the program. This is required for correct non-stop
1056 Indicates the target stopped for a hardware breakpoint. This is
1057 required for correct non-stop mode operation.
1060 Return information about files on the remote system.
1062 qXfer:exec-file:read
1063 Return the full absolute name of the file that was executed to
1064 create a process running on the remote system.
1067 Select the filesystem on which vFile: operations with filename
1068 arguments will operate. This is required for GDB to be able to
1069 access files on remote targets where the remote stub does not
1070 share a common filesystem with the inferior(s).
1073 Indicates that a fork system call was executed.
1076 Indicates that a vfork system call was executed.
1078 vforkdone stop reason
1079 Indicates that a vfork child of the specified process has executed
1080 an exec or exit, allowing the vfork parent to resume execution.
1082 fork-events and vfork-events features in qSupported
1083 The qSupported packet allows GDB to request support for fork and
1084 vfork events using new 'gdbfeatures' fork-events and vfork-events,
1085 and the qSupported response can contain the corresponding
1086 'stubfeatures'. Set and show commands can be used to display
1087 whether these features are enabled.
1089 * Extended-remote fork events
1091 ** GDB now has support for fork events on extended-remote Linux
1092 targets. For targets with Linux kernels 2.5.60 and later, this
1093 enables follow-fork-mode and detach-on-fork for both fork and
1094 vfork, as well as fork and vfork catchpoints.
1096 * The info record command now shows the recording format and the
1097 branch tracing configuration for the current thread when using
1098 the btrace record target.
1099 For the BTS format, it shows the ring buffer size.
1101 * GDB now has support for DTrace USDT (Userland Static Defined
1102 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
1104 * GDB now supports access to vector registers on S/390 GNU/Linux
1107 * Removed command line options
1109 -xdb HP-UX XDB compatibility mode.
1111 * Removed targets and native configurations
1113 HP/PA running HP-UX hppa*-*-hpux*
1114 Itanium running HP-UX ia64-*-hpux*
1116 * New configure options
1119 This configure option allows the user to build GDB with support for
1120 Intel Processor Trace (default: auto). This requires libipt.
1122 --with-libipt-prefix=PATH
1123 Specify the path to the version of libipt that GDB should use.
1124 $PATH/include should contain the intel-pt.h header and
1125 $PATH/lib should contain the libipt.so library.
1127 *** Changes in GDB 7.9.1
1131 ** Xmethods can now specify a result type.
1133 *** Changes in GDB 7.9
1135 * GDB now supports hardware watchpoints on x86 GNU Hurd.
1139 ** You can now access frame registers from Python scripts.
1140 ** New attribute 'producer' for gdb.Symtab objects.
1141 ** gdb.Objfile objects have a new attribute "progspace",
1142 which is the gdb.Progspace object of the containing program space.
1143 ** gdb.Objfile objects have a new attribute "owner".
1144 ** gdb.Objfile objects have a new attribute "build_id",
1145 which is the build ID generated when the file was built.
1146 ** gdb.Objfile objects have a new method "add_separate_debug_file".
1147 ** A new event "gdb.clear_objfiles" has been added, triggered when
1148 selecting a new file to debug.
1149 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
1150 ** New function gdb.lookup_objfile.
1152 New events which are triggered when GDB modifies the state of the
1155 ** gdb.events.inferior_call_pre: Function call is about to be made.
1156 ** gdb.events.inferior_call_post: Function call has just been made.
1157 ** gdb.events.memory_changed: A memory location has been altered.
1158 ** gdb.events.register_changed: A register has been altered.
1160 * New Python-based convenience functions:
1162 ** $_caller_is(name [, number_of_frames])
1163 ** $_caller_matches(regexp [, number_of_frames])
1164 ** $_any_caller_is(name [, number_of_frames])
1165 ** $_any_caller_matches(regexp [, number_of_frames])
1167 * GDB now supports the compilation and injection of source code into
1168 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
1169 to compile the source code to object code, and if successful, inject
1170 and execute that code within the current context of the inferior.
1171 Currently the C language is supported. The commands used to
1172 interface with this new feature are:
1174 compile code [-raw|-r] [--] [source code]
1175 compile file [-raw|-r] filename
1179 demangle [-l language] [--] name
1180 Demangle "name" in the specified language, or the current language
1181 if elided. This command is renamed from the "maint demangle" command.
1182 The latter is kept as a no-op to avoid "maint demangle" being interpreted
1183 as "maint demangler-warning".
1185 queue-signal signal-name-or-number
1186 Queue a signal to be delivered to the thread when it is resumed.
1188 add-auto-load-scripts-directory directory
1189 Add entries to the list of directories from which to load auto-loaded
1192 maint print user-registers
1193 List all currently available "user" registers.
1195 compile code [-r|-raw] [--] [source code]
1196 Compile, inject, and execute in the inferior the executable object
1197 code produced by compiling the provided source code.
1199 compile file [-r|-raw] filename
1200 Compile and inject into the inferior the executable object code
1201 produced by compiling the source code stored in the filename
1204 * On resume, GDB now always passes the signal the program had stopped
1205 for to the thread the signal was sent to, even if the user changed
1206 threads before resuming. Previously GDB would often (but not
1207 always) deliver the signal to the thread that happens to be current
1210 * Conversely, the "signal" command now consistently delivers the
1211 requested signal to the current thread. GDB now asks for
1212 confirmation if the program had stopped for a signal and the user
1213 switched threads meanwhile.
1215 * "breakpoint always-inserted" modes "off" and "auto" merged.
1217 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
1218 won't remove breakpoints from the target until all threads stop,
1219 even in non-stop mode. The "auto" mode has been removed, and "off"
1220 is now the default mode.
1224 set debug symbol-lookup
1225 show debug symbol-lookup
1226 Control display of debugging info regarding symbol lookup.
1230 ** The -list-thread-groups command outputs an exit-code field for
1231 inferiors that have exited.
1235 MIPS SDE mips*-sde*-elf*
1239 Support for these obsolete configurations has been removed.
1241 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
1242 SGI Irix-5.x mips-*-irix5*
1243 SGI Irix-6.x mips-*-irix6*
1244 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
1245 VAX running Ultrix vax-*-ultrix*
1247 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1248 and "assf"), have been removed. Use the "sharedlibrary" command, or
1249 its alias "share", instead.
1251 *** Changes in GDB 7.8
1253 * New command line options
1256 This is an alias for the --data-directory option.
1258 * GDB supports printing and modifying of variable length automatic arrays
1259 as specified in ISO C99.
1261 * The ARM simulator now supports instruction level tracing
1262 with or without disassembly.
1266 GDB now has support for scripting using Guile. Whether this is
1267 available is determined at configure time.
1268 Guile version 2.0 or greater is required.
1269 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
1271 * New commands (for set/show, see "New options" below)
1275 Invoke CODE by passing it to the Guile interpreter.
1279 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
1281 info auto-load guile-scripts [regexp]
1282 Print the list of automatically loaded Guile scripts.
1284 * The source command is now capable of sourcing Guile scripts.
1285 This feature is dependent on the debugger being built with Guile support.
1289 set print symbol-loading (off|brief|full)
1290 show print symbol-loading
1291 Control whether to print informational messages when loading symbol
1292 information for a file. The default is "full", but when debugging
1293 programs with large numbers of shared libraries the amount of output
1294 becomes less useful.
1296 set guile print-stack (none|message|full)
1297 show guile print-stack
1298 Show a stack trace when an error is encountered in a Guile script.
1300 set auto-load guile-scripts (on|off)
1301 show auto-load guile-scripts
1302 Control auto-loading of Guile script files.
1304 maint ada set ignore-descriptive-types (on|off)
1305 maint ada show ignore-descriptive-types
1306 Control whether the debugger should ignore descriptive types in Ada
1307 programs. The default is not to ignore the descriptive types. See
1308 the user manual for more details on descriptive types and the intended
1309 usage of this option.
1311 set auto-connect-native-target
1313 Control whether GDB is allowed to automatically connect to the
1314 native target for the run, attach, etc. commands when not connected
1315 to any target yet. See also "target native" below.
1317 set record btrace replay-memory-access (read-only|read-write)
1318 show record btrace replay-memory-access
1319 Control what memory accesses are allowed during replay.
1321 maint set target-async (on|off)
1322 maint show target-async
1323 This controls whether GDB targets operate in synchronous or
1324 asynchronous mode. Normally the default is asynchronous, if it is
1325 available; but this can be changed to more easily debug problems
1326 occurring only in synchronous mode.
1328 set mi-async (on|off)
1330 Control whether MI asynchronous mode is preferred. This supersedes
1331 "set target-async" of previous GDB versions.
1333 * "set target-async" is deprecated as a CLI option and is now an alias
1334 for "set mi-async" (only puts MI into async mode).
1336 * Background execution commands (e.g., "c&", "s&", etc.) are now
1337 possible ``out of the box'' if the target supports them. Previously
1338 the user would need to explicitly enable the possibility with the
1339 "set target-async on" command.
1341 * New features in the GDB remote stub, GDBserver
1343 ** New option --debug-format=option1[,option2,...] allows one to add
1344 additional text to each output. At present only timestamps
1345 are supported: --debug-format=timestamps.
1346 Timestamps can also be turned on with the
1347 "monitor set debug-format timestamps" command from GDB.
1349 * The 'record instruction-history' command now starts counting instructions
1350 at one. This also affects the instruction ranges reported by the
1351 'record function-call-history' command when given the /i modifier.
1353 * The command 'record function-call-history' supports a new modifier '/c' to
1354 indent the function names based on their call stack depth.
1355 The fields for the '/i' and '/l' modifier have been reordered.
1356 The source line range is now prefixed with 'at'.
1357 The instruction range is now prefixed with 'inst'.
1358 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1359 "record instruction-history" and "list" commands.
1361 * The ranges given as arguments to the 'record function-call-history' and
1362 'record instruction-history' commands are now inclusive.
1364 * The btrace record target now supports the 'record goto' command.
1365 For locations inside the execution trace, the back trace is computed
1366 based on the information stored in the execution trace.
1368 * The btrace record target supports limited reverse execution and replay.
1369 The target does not record data and therefore does not allow reading
1370 memory or registers.
1372 * The "catch syscall" command now works on s390*-linux* targets.
1374 * The "compare-sections" command is no longer specific to target
1375 remote. It now works with all targets.
1377 * All native targets are now consistently called "native".
1378 Consequently, the "target child", "target GNU", "target djgpp",
1379 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1380 commands have been replaced with "target native". The QNX/NTO port
1381 leaves the "procfs" target in place and adds a "native" target for
1382 consistency with other ports. The impact on users should be minimal
1383 as these commands previously either throwed an error, or were
1384 no-ops. The target's name is visible in the output of the following
1385 commands: "help target", "info target", "info files", "maint print
1388 * The "target native" command now connects to the native target. This
1389 can be used to launch native programs even when "set
1390 auto-connect-native-target" is set to off.
1392 * GDB now supports access to Intel MPX registers on GNU/Linux.
1394 * Support for Intel AVX-512 registers on GNU/Linux.
1395 Support displaying and modifying Intel AVX-512 registers
1396 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1398 * New remote packets
1400 qXfer:btrace:read's annex
1401 The qXfer:btrace:read packet supports a new annex 'delta' to read
1402 branch trace incrementally.
1406 ** Valid Python operations on gdb.Value objects representing
1407 structs/classes invoke the corresponding overloaded operators if
1409 ** New `Xmethods' feature in the Python API. Xmethods are
1410 additional methods or replacements for existing methods of a C++
1411 class. This feature is useful for those cases where a method
1412 defined in C++ source code could be inlined or optimized out by
1413 the compiler, making it unavailable to GDB.
1416 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1418 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1419 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1420 its alias "share", instead.
1422 * The commands "set remotebaud" and "show remotebaud" are no longer
1423 supported. Use "set serial baud" and "show serial baud" (respectively)
1428 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1429 target-async". The latter is left as a deprecated alias of the
1430 former for backward compatibility. If the target supports it,
1431 CLI background execution commands are now always possible by
1432 default, independently of whether the frontend stated a
1433 preference for asynchronous execution with "-gdb-set mi-async".
1434 Previously "-gdb-set target-async off" affected both MI execution
1435 commands and CLI execution commands.
1437 *** Changes in GDB 7.7
1439 * Improved support for process record-replay and reverse debugging on
1440 arm*-linux* targets. Support for thumb32 and syscall instruction
1441 recording has been added.
1443 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1445 * GDB now supports Fission DWP file format version 2.
1446 http://gcc.gnu.org/wiki/DebugFission
1448 * New convenience function "$_isvoid", to check whether an expression
1449 is void. A void expression is an expression where the type of the
1450 result is "void". For example, some convenience variables may be
1451 "void" when evaluated (e.g., "$_exitcode" before the execution of
1452 the program being debugged; or an undefined convenience variable).
1453 Another example, when calling a function whose return type is
1456 * The "maintenance print objfiles" command now takes an optional regexp.
1458 * The "catch syscall" command now works on arm*-linux* targets.
1460 * GDB now consistently shows "<not saved>" when printing values of
1461 registers the debug info indicates have not been saved in the frame
1462 and there's nowhere to retrieve them from
1463 (callee-saved/call-clobbered registers):
1468 (gdb) info registers rax
1471 Before, the former would print "<optimized out>", and the latter
1472 "*value not available*".
1474 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1479 ** Frame filters and frame decorators have been added.
1480 ** Temporary breakpoints are now supported.
1481 ** Line tables representation has been added.
1482 ** New attribute 'parent_type' for gdb.Field objects.
1483 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1484 ** New attribute 'name' for gdb.Type objects.
1488 Nios II ELF nios2*-*-elf
1489 Nios II GNU/Linux nios2*-*-linux
1490 Texas Instruments MSP430 msp430*-*-elf
1492 * Removed native configurations
1494 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1495 been removed. ELF variants of these configurations are kept supported.
1497 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1498 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1499 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1500 i[34567]86-*-openbsd3.[0-3]
1501 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1502 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1503 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1507 Like "catch throw", but catches a re-thrown exception.
1508 maint check-psymtabs
1509 Renamed from old "maint check-symtabs".
1511 Perform consistency checks on symtabs.
1512 maint expand-symtabs
1513 Expand symtabs matching an optional regexp.
1516 Display the details of GDB configure-time options.
1518 maint set|show per-command
1519 maint set|show per-command space
1520 maint set|show per-command time
1521 maint set|show per-command symtab
1522 Enable display of per-command gdb resource usage.
1524 remove-symbol-file FILENAME
1525 remove-symbol-file -a ADDRESS
1526 Remove a symbol file added via add-symbol-file. The file to remove
1527 can be identified by its filename or by an address that lies within
1528 the boundaries of this symbol file in memory.
1531 info exceptions REGEXP
1532 Display the list of Ada exceptions defined in the program being
1533 debugged. If provided, only the exceptions whose names match REGEXP
1538 set debug symfile off|on
1540 Control display of debugging info regarding reading symbol files and
1541 symbol tables within those files
1543 set print raw frame-arguments
1544 show print raw frame-arguments
1545 Set/show whether to print frame arguments in raw mode,
1546 disregarding any defined pretty-printers.
1548 set remote trace-status-packet
1549 show remote trace-status-packet
1550 Set/show the use of remote protocol qTStatus packet.
1554 Control display of debugging messages related to Nios II targets.
1558 Control whether target-assisted range stepping is enabled.
1560 set startup-with-shell
1561 show startup-with-shell
1562 Specifies whether Unix child processes are started via a shell or
1567 Use the target memory cache for accesses to the code segment. This
1568 improves performance of remote debugging (particularly disassembly).
1570 * You can now use a literal value 'unlimited' for options that
1571 interpret 0 or -1 as meaning "unlimited". E.g., "set
1572 trace-buffer-size unlimited" is now an alias for "set
1573 trace-buffer-size -1" and "set height unlimited" is now an alias for
1576 * The "set debug symtab-create" debugging option of GDB has been changed to
1577 accept a verbosity level. 0 means "off", 1 provides basic debugging
1578 output, and values of 2 or greater provides more verbose output.
1580 * New command-line options
1582 Display the details of GDB configure-time options.
1584 * The command 'tsave' can now support new option '-ctf' to save trace
1585 buffer in Common Trace Format.
1587 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1590 * GDB now implements the the C++ 'typeid' operator.
1592 * The new convenience variable $_exception holds the exception being
1593 thrown or caught at an exception-related catchpoint.
1595 * The exception-related catchpoints, like "catch throw", now accept a
1596 regular expression which can be used to filter exceptions by type.
1598 * The new convenience variable $_exitsignal is automatically set to
1599 the terminating signal number when the program being debugged dies
1600 due to an uncaught signal.
1604 ** All MI commands now accept an optional "--language" option.
1605 Support for this feature can be verified by using the "-list-features"
1606 command, which should contain "language-option".
1608 ** The new command -info-gdb-mi-command allows the user to determine
1609 whether a GDB/MI command is supported or not.
1611 ** The "^error" result record returned when trying to execute an undefined
1612 GDB/MI command now provides a variable named "code" whose content is the
1613 "undefined-command" error code. Support for this feature can be verified
1614 by using the "-list-features" command, which should contain
1615 "undefined-command-error-code".
1617 ** The -trace-save MI command can optionally save trace buffer in Common
1620 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1622 ** The command -data-list-register-values now accepts an optional
1623 "--skip-unavailable" option. When used, only the available registers
1626 ** The new command -trace-frame-collected dumps collected variables,
1627 computed expressions, tvars, memory and registers in a traceframe.
1629 ** The commands -stack-list-locals, -stack-list-arguments and
1630 -stack-list-variables now accept an option "--skip-unavailable".
1631 When used, only the available locals or arguments are displayed.
1633 ** The -exec-run command now accepts an optional "--start" option.
1634 When used, the command follows the same semantics as the "start"
1635 command, stopping the program's execution at the start of its
1636 main subprogram. Support for this feature can be verified using
1637 the "-list-features" command, which should contain
1638 "exec-run-start-option".
1640 ** The new commands -catch-assert and -catch-exceptions insert
1641 catchpoints stopping the program when Ada exceptions are raised.
1643 ** The new command -info-ada-exceptions provides the equivalent of
1644 the new "info exceptions" command.
1646 * New system-wide configuration scripts
1647 A GDB installation now provides scripts suitable for use as system-wide
1648 configuration scripts for the following systems:
1652 * GDB now supports target-assigned range stepping with remote targets.
1653 This improves the performance of stepping source lines by reducing
1654 the number of control packets from/to GDB. See "New remote packets"
1657 * GDB now understands the element 'tvar' in the XML traceframe info.
1658 It has the id of the collected trace state variables.
1660 * On S/390 targets that provide the transactional-execution feature,
1661 the program interruption transaction diagnostic block (TDB) is now
1662 represented as a number of additional "registers" in GDB.
1664 * New remote packets
1668 The vCont packet supports a new 'r' action, that tells the remote
1669 stub to step through an address range itself, without GDB
1670 involvemement at each single-step.
1672 qXfer:libraries-svr4:read's annex
1673 The previously unused annex of the qXfer:libraries-svr4:read packet
1674 is now used to support passing an argument list. The remote stub
1675 reports support for this argument list to GDB's qSupported query.
1676 The defined arguments are "start" and "prev", used to reduce work
1677 necessary for library list updating, resulting in significant
1680 * New features in the GDB remote stub, GDBserver
1682 ** GDBserver now supports target-assisted range stepping. Currently
1683 enabled on x86/x86_64 GNU/Linux targets.
1685 ** GDBserver now adds element 'tvar' in the XML in the reply to
1686 'qXfer:traceframe-info:read'. It has the id of the collected
1687 trace state variables.
1689 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1692 * New 'z' formatter for printing and examining memory, this displays the
1693 value as hexadecimal zero padded on the left to the size of the type.
1695 * GDB can now use Windows x64 unwinding data.
1697 * The "set remotebaud" command has been replaced by "set serial baud".
1698 Similarly, "show remotebaud" has been replaced by "show serial baud".
1699 The "set remotebaud" and "show remotebaud" commands are still available
1700 to provide backward compatibility with older versions of GDB.
1702 *** Changes in GDB 7.6
1704 * Target record has been renamed to record-full.
1705 Record/replay is now enabled with the "record full" command.
1706 This also affects settings that are associated with full record/replay
1707 that have been moved from "set/show record" to "set/show record full":
1709 set|show record full insn-number-max
1710 set|show record full stop-at-limit
1711 set|show record full memory-query
1713 * A new record target "record-btrace" has been added. The new target
1714 uses hardware support to record the control-flow of a process. It
1715 does not support replaying the execution, but it implements the
1716 below new commands for investigating the recorded execution log.
1717 This new recording method can be enabled using:
1721 The "record-btrace" target is only available on Intel Atom processors
1722 and requires a Linux kernel 2.6.32 or later.
1724 * Two new commands have been added for record/replay to give information
1725 about the recorded execution without having to replay the execution.
1726 The commands are only supported by "record btrace".
1728 record instruction-history prints the execution history at
1729 instruction granularity
1731 record function-call-history prints the execution history at
1732 function granularity
1734 * New native configurations
1736 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1737 FreeBSD/powerpc powerpc*-*-freebsd
1738 x86_64/Cygwin x86_64-*-cygwin*
1739 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1743 ARM AArch64 aarch64*-*-elf
1744 ARM AArch64 GNU/Linux aarch64*-*-linux
1745 Lynx 178 PowerPC powerpc-*-lynx*178
1746 x86_64/Cygwin x86_64-*-cygwin*
1747 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1749 * If the configured location of system.gdbinit file (as given by the
1750 --with-system-gdbinit option at configure time) is in the
1751 data-directory (as specified by --with-gdb-datadir at configure
1752 time) or in one of its subdirectories, then GDB will look for the
1753 system-wide init file in the directory specified by the
1754 --data-directory command-line option.
1756 * New command line options:
1758 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1759 other initialization files, unlike -nx which disables all of them.
1761 * Removed command line options
1763 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1766 * The 'ptype' and 'whatis' commands now accept an argument to control
1769 * 'info proc' now works on some core files.
1773 ** Vectors can be created with gdb.Type.vector.
1775 ** Python's atexit.register now works in GDB.
1777 ** Types can be pretty-printed via a Python API.
1779 ** Python 3 is now supported (in addition to Python 2.4 or later)
1781 ** New class gdb.Architecture exposes GDB's internal representation
1782 of architecture in the Python API.
1784 ** New method Frame.architecture returns the gdb.Architecture object
1785 corresponding to the frame's architecture.
1787 * New Python-based convenience functions:
1789 ** $_memeq(buf1, buf2, length)
1790 ** $_streq(str1, str2)
1792 ** $_regex(str, regex)
1794 * The 'cd' command now defaults to using '~' (the home directory) if not
1797 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1798 default for GCC since November 2000.
1800 * The command 'forward-search' can now be abbreviated as 'fo'.
1802 * The command 'info tracepoints' can now display 'installed on target'
1803 or 'not installed on target' for each non-pending location of tracepoint.
1805 * New configure options
1807 --enable-libmcheck/--disable-libmcheck
1808 By default, development versions are built with -lmcheck on hosts
1809 that support it, in order to help track memory corruption issues.
1810 Release versions, on the other hand, are built without -lmcheck
1811 by default. The --enable-libmcheck/--disable-libmcheck configure
1812 options allow the user to override that default.
1813 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1814 This configure option allows the user to build GDB with
1815 libbabeltrace using which GDB can read Common Trace Format data.
1817 * New commands (for set/show, see "New options" below)
1820 Catch signals. This is similar to "handle", but allows commands and
1821 conditions to be attached.
1824 List the BFDs known to GDB.
1826 python-interactive [command]
1828 Start a Python interactive prompt, or evaluate the optional command
1829 and print the result of expressions.
1832 "py" is a new alias for "python".
1834 enable type-printer [name]...
1835 disable type-printer [name]...
1836 Enable or disable type printers.
1840 ** For the Renesas Super-H architecture, the "regs" command has been removed
1841 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1846 set print type methods (on|off)
1847 show print type methods
1848 Control whether method declarations are displayed by "ptype".
1849 The default is to show them.
1851 set print type typedefs (on|off)
1852 show print type typedefs
1853 Control whether typedef definitions are displayed by "ptype".
1854 The default is to show them.
1856 set filename-display basename|relative|absolute
1857 show filename-display
1858 Control the way in which filenames is displayed.
1859 The default is "relative", which preserves previous behavior.
1861 set trace-buffer-size
1862 show trace-buffer-size
1863 Request target to change the size of trace buffer.
1865 set remote trace-buffer-size-packet auto|on|off
1866 show remote trace-buffer-size-packet
1867 Control the use of the remote protocol `QTBuffer:size' packet.
1871 Control display of debugging messages related to ARM AArch64.
1874 set debug coff-pe-read
1875 show debug coff-pe-read
1876 Control display of debugging messages related to reading of COFF/PE
1881 Control display of debugging messages related to Mach-O symbols
1884 set debug notification
1885 show debug notification
1886 Control display of debugging info for async remote notification.
1890 ** Command parameter changes are now notified using new async record
1891 "=cmd-param-changed".
1892 ** Trace frame changes caused by command "tfind" are now notified using
1893 new async record "=traceframe-changed".
1894 ** The creation, deletion and modification of trace state variables
1895 are now notified using new async records "=tsv-created",
1896 "=tsv-deleted" and "=tsv-modified".
1897 ** The start and stop of process record are now notified using new
1898 async record "=record-started" and "=record-stopped".
1899 ** Memory changes are now notified using new async record
1901 ** The data-disassemble command response will include a "fullname" field
1902 containing the absolute file name when source has been requested.
1903 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1904 command, to allow pattern filling of memory areas.
1905 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1906 library load/unload events.
1907 ** The response to breakpoint commands and breakpoint async records
1908 includes an "installed" field containing a boolean state about each
1909 non-pending tracepoint location is whether installed on target or not.
1910 ** Output of the "-trace-status" command includes a "trace-file" field
1911 containing the name of the trace file being examined. This field is
1912 optional, and only present when examining a trace file.
1913 ** The "fullname" field is now always present along with the "file" field,
1914 even if the file cannot be found by GDB.
1916 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1917 You must have the LZMA library available when configuring GDB for this
1918 feature to be enabled. For more information, see:
1919 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1921 * New remote packets
1924 Set the size of trace buffer. The remote stub reports support for this
1925 packet to gdb's qSupported query.
1928 Enable Branch Trace Store (BTS)-based branch tracing for the current
1929 thread. The remote stub reports support for this packet to gdb's
1933 Disable branch tracing for the current thread. The remote stub reports
1934 support for this packet to gdb's qSupported query.
1937 Read the traced branches for the current thread. The remote stub
1938 reports support for this packet to gdb's qSupported query.
1940 *** Changes in GDB 7.5
1942 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1943 for more x32 ABI info.
1945 * GDB now supports access to MIPS DSP registers on Linux targets.
1947 * GDB now supports debugging microMIPS binaries.
1949 * The "info os" command on GNU/Linux can now display information on
1950 several new classes of objects managed by the operating system:
1951 "info os procgroups" lists process groups
1952 "info os files" lists file descriptors
1953 "info os sockets" lists internet-domain sockets
1954 "info os shm" lists shared-memory regions
1955 "info os semaphores" lists semaphores
1956 "info os msg" lists message queues
1957 "info os modules" lists loaded kernel modules
1959 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1960 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1961 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1962 options and inspect the probe arguments using the new $_probe_arg family
1963 of convenience variables. You can obtain more information about SystemTap
1964 in <http://sourceware.org/systemtap/>.
1966 * GDB now supports reversible debugging on ARM, it allows you to
1967 debug basic ARM and THUMB instructions, and provides
1968 record/replay support.
1970 * The option "symbol-reloading" has been deleted as it is no longer used.
1974 ** GDB commands implemented in Python can now be put in command class
1977 ** The "maint set python print-stack on|off" is now deleted.
1979 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1980 apply "flag enum"-style pretty-printing to any enum.
1982 ** gdb.lookup_symbol can now work when there is no current frame.
1984 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1985 the source at which the symbol was defined.
1987 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1988 method 'value'. The former indicates whether the symbol needs a
1989 frame in order to compute its value, and the latter computes the
1992 ** A new method 'referenced_value' on gdb.Value objects which can
1993 dereference pointer as well as C++ reference values.
1995 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1996 which return the global and static blocks (as gdb.Block objects),
1997 of the underlying symbol table, respectively.
1999 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
2000 object associated with a PC value.
2002 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
2003 of the address range occupied by code for the current source line.
2005 * Go language support.
2006 GDB now supports debugging programs written in the Go programming
2009 * GDBserver now supports stdio connections.
2010 E.g. (gdb) target remote | ssh myhost gdbserver - hello
2012 * The binary "gdbtui" can no longer be built or installed.
2013 Use "gdb -tui" instead.
2015 * GDB will now print "flag" enums specially. A flag enum is one where
2016 all the enumerator values have no bits in common when pairwise
2017 "and"ed. When printing a value whose type is a flag enum, GDB will
2018 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
2019 (gdb) print (enum E) 3
2022 * The filename part of a linespec will now match trailing components
2023 of a source file name. For example, "break gcc/expr.c:1000" will
2024 now set a breakpoint in build/gcc/expr.c, but not
2025 build/libcpp/expr.c.
2027 * The "info proc" and "generate-core-file" commands will now also
2028 work on remote targets connected to GDBserver on Linux.
2030 * The command "info catch" has been removed. It has been disabled
2031 since December 2007.
2033 * The "catch exception" and "catch assert" commands now accept
2034 a condition at the end of the command, much like the "break"
2035 command does. For instance:
2037 (gdb) catch exception Constraint_Error if Barrier = True
2039 Previously, it was possible to add a condition to such catchpoints,
2040 but it had to be done as a second step, after the catchpoint had been
2041 created, using the "condition" command.
2043 * The "info static-tracepoint-marker" command will now also work on
2044 native Linux targets with in-process agent.
2046 * GDB can now set breakpoints on inlined functions.
2048 * The .gdb_index section has been updated to include symbols for
2049 inlined functions. GDB will ignore older .gdb_index sections by
2050 default, which could cause symbol files to be loaded more slowly
2051 until their .gdb_index sections can be recreated. The new command
2052 "set use-deprecated-index-sections on" will cause GDB to use any older
2053 .gdb_index sections it finds. This will restore performance, but the
2054 ability to set breakpoints on inlined functions will be lost in symbol
2055 files with older .gdb_index sections.
2057 The .gdb_index section has also been updated to record more information
2058 about each symbol. This speeds up the "info variables", "info functions"
2059 and "info types" commands when used with programs having the .gdb_index
2060 section, as well as speeding up debugging with shared libraries using
2061 the .gdb_index section.
2063 * Ada support for GDB/MI Variable Objects has been added.
2065 * GDB can now support 'breakpoint always-inserted mode' in 'record'
2070 ** New command -info-os is the MI equivalent of "info os".
2072 ** Output logs ("set logging" and related) now include MI output.
2076 ** "set use-deprecated-index-sections on|off"
2077 "show use-deprecated-index-sections on|off"
2078 Controls the use of deprecated .gdb_index sections.
2080 ** "catch load" and "catch unload" can be used to stop when a shared
2081 library is loaded or unloaded, respectively.
2083 ** "enable count" can be used to auto-disable a breakpoint after
2086 ** "info vtbl" can be used to show the virtual method tables for
2087 C++ and Java objects.
2089 ** "explore" and its sub commands "explore value" and "explore type"
2090 can be used to recursively explore values and types of
2091 expressions. These commands are available only if GDB is
2092 configured with '--with-python'.
2094 ** "info auto-load" shows status of all kinds of auto-loaded files,
2095 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
2096 sequences of commands files, "info auto-load python-scripts"
2097 shows status of auto-loading Python script files,
2098 "info auto-load local-gdbinit" shows status of loading init file
2099 (.gdbinit) from current directory and "info auto-load libthread-db" shows
2100 status of inferior specific thread debugging shared library loading.
2102 ** "info auto-load-scripts", "set auto-load-scripts on|off"
2103 and "show auto-load-scripts" commands have been deprecated, use their
2104 "info auto-load python-scripts", "set auto-load python-scripts on|off"
2105 and "show auto-load python-scripts" counterparts instead.
2107 ** "dprintf location,format,args..." creates a dynamic printf, which
2108 is basically a breakpoint that does a printf and immediately
2109 resumes your program's execution, so it is like a printf that you
2110 can insert dynamically at runtime instead of at compiletime.
2112 ** "set print symbol"
2114 Controls whether GDB attempts to display the symbol, if any,
2115 corresponding to addresses it prints. This defaults to "on", but
2116 you can set it to "off" to restore GDB's previous behavior.
2118 * Deprecated commands
2120 ** For the Renesas Super-H architecture, the "regs" command has been
2121 deprecated, and "info all-registers" should be used instead.
2125 Renesas RL78 rl78-*-elf
2126 HP OpenVMS ia64 ia64-hp-openvms*
2128 * GDBserver supports evaluation of breakpoint conditions. When
2129 support is advertised by GDBserver, GDB may be told to send the
2130 breakpoint conditions in bytecode form to GDBserver. GDBserver
2131 will only report the breakpoint trigger to GDB when its condition
2136 set mips compression
2137 show mips compression
2138 Select the compressed ISA encoding used in functions that have no symbol
2139 information available. The encoding can be set to either of:
2142 and is updated automatically from ELF file flags if available.
2144 set breakpoint condition-evaluation
2145 show breakpoint condition-evaluation
2146 Control whether breakpoint conditions are evaluated by GDB ("host") or by
2147 GDBserver ("target"). Default option "auto" chooses the most efficient
2149 This option can improve debugger efficiency depending on the speed of the
2153 Disable auto-loading globally.
2156 Show auto-loading setting of all kinds of auto-loaded files.
2158 set auto-load gdb-scripts on|off
2159 show auto-load gdb-scripts
2160 Control auto-loading of GDB canned sequences of commands files.
2162 set auto-load python-scripts on|off
2163 show auto-load python-scripts
2164 Control auto-loading of Python script files.
2166 set auto-load local-gdbinit on|off
2167 show auto-load local-gdbinit
2168 Control loading of init file (.gdbinit) from current directory.
2170 set auto-load libthread-db on|off
2171 show auto-load libthread-db
2172 Control auto-loading of inferior specific thread debugging shared library.
2174 set auto-load scripts-directory <dir1>[:<dir2>...]
2175 show auto-load scripts-directory
2176 Set a list of directories from which to load auto-loaded scripts.
2177 Automatically loaded Python scripts and GDB scripts are located in one
2178 of the directories listed by this option.
2179 The delimiter (':' above) may differ according to the host platform.
2181 set auto-load safe-path <dir1>[:<dir2>...]
2182 show auto-load safe-path
2183 Set a list of directories from which it is safe to auto-load files.
2184 The delimiter (':' above) may differ according to the host platform.
2186 set debug auto-load on|off
2187 show debug auto-load
2188 Control display of debugging info for auto-loading the files above.
2190 set dprintf-style gdb|call|agent
2192 Control the way in which a dynamic printf is performed; "gdb"
2193 requests a GDB printf command, while "call" causes dprintf to call a
2194 function in the inferior. "agent" requests that the target agent
2195 (such as GDBserver) do the printing.
2197 set dprintf-function <expr>
2198 show dprintf-function
2199 set dprintf-channel <expr>
2200 show dprintf-channel
2201 Set the function and optional first argument to the call when using
2202 the "call" style of dynamic printf.
2204 set disconnected-dprintf on|off
2205 show disconnected-dprintf
2206 Control whether agent-style dynamic printfs continue to be in effect
2207 after GDB disconnects.
2209 * New configure options
2211 --with-auto-load-dir
2212 Configure default value for the 'set auto-load scripts-directory'
2213 setting above. It defaults to '$debugdir:$datadir/auto-load',
2214 $debugdir representing global debugging info directories (available
2215 via 'show debug-file-directory') and $datadir representing GDB's data
2216 directory (available via 'show data-directory').
2218 --with-auto-load-safe-path
2219 Configure default value for the 'set auto-load safe-path' setting
2220 above. It defaults to the --with-auto-load-dir setting.
2222 --without-auto-load-safe-path
2223 Set 'set auto-load safe-path' to '/', effectively disabling this
2226 * New remote packets
2228 z0/z1 conditional breakpoints extension
2230 The z0/z1 breakpoint insertion packets have been extended to carry
2231 a list of conditional expressions over to the remote stub depending on the
2232 condition evaluation mode. The use of this extension can be controlled
2233 via the "set remote conditional-breakpoints-packet" command.
2237 Specify the signals which the remote stub may pass to the debugged
2238 program without GDB involvement.
2240 * New command line options
2242 --init-command=FILE, -ix Like --command, -x but execute it
2243 before loading inferior.
2244 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
2245 execute it before loading inferior.
2247 *** Changes in GDB 7.4
2249 * GDB now handles ambiguous linespecs more consistently; the existing
2250 FILE:LINE support has been expanded to other types of linespecs. A
2251 breakpoint will now be set on all matching locations in all
2252 inferiors, and locations will be added or removed according to
2255 * GDB now allows you to skip uninteresting functions and files when
2256 stepping with the "skip function" and "skip file" commands.
2258 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
2259 and "show remote hardware-watchpoint-length-limit". These allows to
2260 set or show the maximum length limit (in bytes) of a remote
2261 target hardware watchpoint.
2263 This allows e.g. to use "unlimited" hardware watchpoints with the
2264 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
2265 watchpoints are slower than real hardware watchpoints but are
2266 significantly faster than gdb software watchpoints.
2270 ** The register_pretty_printer function in module gdb.printing now takes
2271 an optional `replace' argument. If True, the new printer replaces any
2274 ** The "maint set python print-stack on|off" command has been
2275 deprecated and will be deleted in GDB 7.5.
2276 A new command: "set python print-stack none|full|message" has
2277 replaced it. Additionally, the default for "print-stack" is
2278 now "message", which just prints the error message without
2281 ** A prompt substitution hook (prompt_hook) is now available to the
2284 ** A new Python module, gdb.prompt has been added to the GDB Python
2285 modules library. This module provides functionality for
2286 escape sequences in prompts (used by set/show
2287 extended-prompt). These escape sequences are replaced by their
2288 corresponding value.
2290 ** Python commands and convenience-functions located in
2291 'data-directory'/python/gdb/command and
2292 'data-directory'/python/gdb/function are now automatically loaded
2295 ** Blocks now provide four new attributes. global_block and
2296 static_block will return the global and static blocks
2297 respectively. is_static and is_global are boolean attributes
2298 that indicate if the block is one of those two types.
2300 ** Symbols now provide the "type" attribute, the type of the symbol.
2302 ** The "gdb.breakpoint" function has been deprecated in favor of
2305 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2306 of a function. This class is based on the "finish" command
2307 available in the CLI.
2309 ** Type objects for struct and union types now allow access to
2310 the fields using standard Python dictionary (mapping) methods.
2311 For example, "some_type['myfield']" now works, as does
2312 "some_type.items()".
2314 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2317 ** A new function, "deep_items" has been added to the gdb.types
2318 module in the GDB Python modules library. This function returns
2319 an iterator over the fields of a struct or union type. Unlike
2320 the standard Python "iteritems" method, it will recursively traverse
2321 any anonymous fields.
2325 ** "*stopped" events can report several new "reason"s, such as
2328 ** Breakpoint changes are now notified using new async records, like
2329 "=breakpoint-modified".
2331 ** New command -ada-task-info.
2333 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2334 $sdir specifies the default system locations of shared libraries.
2335 $pdir specifies the directory where the libpthread used by the application
2338 GDB no longer looks in $sdir and $pdir after it has searched the directories
2339 mentioned in libthread-db-search-path. If you want to search those
2340 directories, they must be specified in libthread-db-search-path.
2341 The default value of libthread-db-search-path on GNU/Linux and Solaris
2342 systems is now "$sdir:$pdir".
2344 $pdir is not supported by gdbserver, it is currently ignored.
2345 $sdir is supported by gdbserver.
2347 * New configure option --with-iconv-bin.
2348 When using the internationalization support like the one in the GNU C
2349 library, GDB will invoke the "iconv" program to get a list of supported
2350 character sets. If this program lives in a non-standard location, one can
2351 use this option to specify where to find it.
2353 * When natively debugging programs on PowerPC BookE processors running
2354 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2355 watchpoints, which specify a mask in addition to an address to watch.
2356 The mask specifies that some bits of an address (the bits which are
2357 reset in the mask) should be ignored when matching the address accessed
2358 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2359 section in the user manual for more details.
2361 * The new option --once causes GDBserver to stop listening for connections once
2362 the first connection is made. The listening port used by GDBserver will
2363 become available after that.
2365 * New commands "info macros" and "alias" have been added.
2367 * New function parameters suffix @entry specifies value of function parameter
2368 at the time the function got called. Entry values are available only since
2374 "!" is now an alias of the "shell" command.
2375 Note that no space is needed between "!" and SHELL COMMAND.
2379 watch EXPRESSION mask MASK_VALUE
2380 The watch command now supports the mask argument which allows creation
2381 of masked watchpoints, if the current architecture supports this feature.
2383 info auto-load-scripts [REGEXP]
2384 This command was formerly named "maintenance print section-scripts".
2385 It is now generally useful and is no longer a maintenance-only command.
2387 info macro [-all] [--] MACRO
2388 The info macro command has new options `-all' and `--'. The first for
2389 printing all definitions of a macro. The second for explicitly specifying
2390 the end of arguments and the beginning of the macro name in case the macro
2391 name starts with a hyphen.
2393 collect[/s] EXPRESSIONS
2394 The tracepoint collect command now takes an optional modifier "/s"
2395 that directs it to dereference pointer-to-character types and
2396 collect the bytes of memory up to a zero byte. The behavior is
2397 similar to what you see when you use the regular print command on a
2398 string. An optional integer following the "/s" sets a bound on the
2399 number of bytes that will be collected.
2402 The trace start command now interprets any supplied arguments as a
2403 note to be recorded with the trace run, with an effect similar to
2404 setting the variable trace-notes.
2407 The trace stop command now interprets any arguments as a note to be
2408 mentioned along with the tstatus report that the trace was stopped
2409 with a command. The effect is similar to setting the variable
2412 * Tracepoints can now be enabled and disabled at any time after a trace
2413 experiment has been started using the standard "enable" and "disable"
2414 commands. It is now possible to start a trace experiment with no enabled
2415 tracepoints; GDB will display a warning, but will allow the experiment to
2416 begin, assuming that tracepoints will be enabled as needed while the trace
2419 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2420 locations with 4-byte instructions, when they were previously
2421 limited to locations with instructions of 5 bytes or longer.
2425 set debug dwarf2-read
2426 show debug dwarf2-read
2427 Turns on or off display of debugging messages related to reading
2428 DWARF debug info. The default is off.
2430 set debug symtab-create
2431 show debug symtab-create
2432 Turns on or off display of debugging messages related to symbol table
2433 creation. The default is off.
2436 show extended-prompt
2437 Set the GDB prompt, and allow escape sequences to be inserted to
2438 display miscellaneous information (see 'help set extended-prompt'
2439 for the list of sequences). This prompt (and any information
2440 accessed through the escape sequences) is updated every time the
2441 prompt is displayed.
2443 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2444 show print entry-values
2445 Set printing of frame argument values at function entry. In some cases
2446 GDB can determine the value of function argument which was passed by the
2447 function caller, even if the value was modified inside the called function.
2449 set debug entry-values
2450 show debug entry-values
2451 Control display of debugging info for determining frame argument values at
2452 function entry and virtual tail call frames.
2454 set basenames-may-differ
2455 show basenames-may-differ
2456 Set whether a source file may have multiple base names.
2457 (A "base name" is the name of a file with the directory part removed.
2458 Example: The base name of "/home/user/hello.c" is "hello.c".)
2459 If set, GDB will canonicalize file names (e.g., expand symlinks)
2460 before comparing them. Canonicalization is an expensive operation,
2461 but it allows the same file be known by more than one base name.
2462 If not set (the default), all source files are assumed to have just
2463 one base name, and gdb will do file name comparisons more efficiently.
2469 Set a user name and notes for the current and any future trace runs.
2470 This is useful for long-running and/or disconnected traces, to
2471 inform others (or yourself) as to who is running the trace, supply
2472 contact information, or otherwise explain what is going on.
2474 set trace-stop-notes
2475 show trace-stop-notes
2476 Set a note attached to the trace run, that is displayed when the
2477 trace has been stopped by a tstop command. This is useful for
2478 instance as an explanation, if you are stopping a trace run that was
2479 started by someone else.
2481 * New remote packets
2485 Dynamically enable a tracepoint in a started trace experiment.
2489 Dynamically disable a tracepoint in a started trace experiment.
2493 Set the user and notes of the trace run.
2497 Query the current status of a tracepoint.
2501 Query the minimum length of instruction at which a fast tracepoint may
2504 * Dcache size (number of lines) and line-size are now runtime-configurable
2505 via "set dcache line" and "set dcache line-size" commands.
2509 Texas Instruments TMS320C6x tic6x-*-*
2513 Renesas RL78 rl78-*-elf
2515 *** Changes in GDB 7.3.1
2517 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2519 *** Changes in GDB 7.3
2521 * GDB has a new command: "thread find [REGEXP]".
2522 It finds the thread id whose name, target id, or thread extra info
2523 matches the given regular expression.
2525 * The "catch syscall" command now works on mips*-linux* targets.
2527 * The -data-disassemble MI command now supports modes 2 and 3 for
2528 dumping the instruction opcodes.
2530 * New command line options
2532 -data-directory DIR Specify DIR as the "data-directory".
2533 This is mostly for testing purposes.
2535 * The "maint set python auto-load on|off" command has been renamed to
2536 "set auto-load-scripts on|off".
2538 * GDB has a new command: "set directories".
2539 It is like the "dir" command except that it replaces the
2540 source path list instead of augmenting it.
2542 * GDB now understands thread names.
2544 On GNU/Linux, "info threads" will display the thread name as set by
2545 prctl or pthread_setname_np.
2547 There is also a new command, "thread name", which can be used to
2548 assign a name internally for GDB to display.
2551 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2552 has been integrated into GDB.
2556 ** The function gdb.Write now accepts an optional keyword 'stream'.
2557 This keyword, when provided, will direct the output to either
2558 stdout, stderr, or GDB's logging output.
2560 ** Parameters can now be be sub-classed in Python, and in particular
2561 you may implement the get_set_doc and get_show_doc functions.
2562 This improves how Parameter set/show documentation is processed
2563 and allows for more dynamic content.
2565 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2566 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2567 have an is_valid method.
2569 ** Breakpoints can now be sub-classed in Python, and in particular
2570 you may implement a 'stop' function that is executed each time
2571 the inferior reaches that breakpoint.
2573 ** New function gdb.lookup_global_symbol looks up a global symbol.
2575 ** GDB values in Python are now callable if the value represents a
2576 function. For example, if 'some_value' represents a function that
2577 takes two integer parameters and returns a value, you can call
2578 that function like so:
2580 result = some_value (10,20)
2582 ** Module gdb.types has been added.
2583 It contains a collection of utilities for working with gdb.Types objects:
2584 get_basic_type, has_field, make_enum_dict.
2586 ** Module gdb.printing has been added.
2587 It contains utilities for writing and registering pretty-printers.
2588 New classes: PrettyPrinter, SubPrettyPrinter,
2589 RegexpCollectionPrettyPrinter.
2590 New function: register_pretty_printer.
2592 ** New commands "info pretty-printers", "enable pretty-printer" and
2593 "disable pretty-printer" have been added.
2595 ** gdb.parameter("directories") is now available.
2597 ** New function gdb.newest_frame returns the newest frame in the
2600 ** The gdb.InferiorThread class has a new "name" attribute. This
2601 holds the thread's name.
2603 ** Python Support for Inferior events.
2604 Python scripts can add observers to be notified of events
2605 occurring in the process being debugged.
2606 The following events are currently supported:
2607 - gdb.events.cont Continue event.
2608 - gdb.events.exited Inferior exited event.
2609 - gdb.events.stop Signal received, and Breakpoint hit events.
2613 ** GDB now puts template parameters in scope when debugging in an
2614 instantiation. For example, if you have:
2616 template<int X> int func (void) { return X; }
2618 then if you step into func<5>, "print X" will show "5". This
2619 feature requires proper debuginfo support from the compiler; it
2620 was added to GCC 4.5.
2622 ** The motion commands "next", "finish", "until", and "advance" now
2623 work better when exceptions are thrown. In particular, GDB will
2624 no longer lose control of the inferior; instead, the GDB will
2625 stop the inferior at the point at which the exception is caught.
2626 This functionality requires a change in the exception handling
2627 code that was introduced in GCC 4.5.
2629 * GDB now follows GCC's rules on accessing volatile objects when
2630 reading or writing target state during expression evaluation.
2631 One notable difference to prior behavior is that "print x = 0"
2632 no longer generates a read of x; the value of the assignment is
2633 now always taken directly from the value being assigned.
2635 * GDB now has some support for using labels in the program's source in
2636 linespecs. For instance, you can use "advance label" to continue
2637 execution to a label.
2639 * GDB now has support for reading and writing a new .gdb_index
2640 section. This section holds a fast index of DWARF debugging
2641 information and can be used to greatly speed up GDB startup and
2642 operation. See the documentation for `save gdb-index' for details.
2644 * The "watch" command now accepts an optional "-location" argument.
2645 When used, this causes GDB to watch the memory referred to by the
2646 expression. Such a watchpoint is never deleted due to it going out
2649 * GDB now supports thread debugging of core dumps on GNU/Linux.
2651 GDB now activates thread debugging using the libthread_db library
2652 when debugging GNU/Linux core dumps, similarly to when debugging
2653 live processes. As a result, when debugging a core dump file, GDB
2654 is now able to display pthread_t ids of threads. For example, "info
2655 threads" shows the same output as when debugging the process when it
2656 was live. In earlier releases, you'd see something like this:
2659 * 1 LWP 6780 main () at main.c:10
2661 While now you see this:
2664 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2666 It is also now possible to inspect TLS variables when debugging core
2669 When debugging a core dump generated on a machine other than the one
2670 used to run GDB, you may need to point GDB at the correct
2671 libthread_db library with the "set libthread-db-search-path"
2672 command. See the user manual for more details on this command.
2674 * When natively debugging programs on PowerPC BookE processors running
2675 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2676 which stop execution of the inferior whenever it executes an instruction
2677 at any address within the specified range. See the "PowerPC Embedded"
2678 section in the user manual for more details.
2680 * New features in the GDB remote stub, GDBserver
2682 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2683 and i686 LynxOS (version 5.x).
2685 ** GDBserver is now supported on Blackfin Linux.
2687 * New native configurations
2689 ia64 HP-UX ia64-*-hpux*
2693 Analog Devices, Inc. Blackfin Processor bfin-*
2695 * Ada task switching is now supported on sparc-elf targets when
2696 debugging a program using the Ravenscar Profile. For more information,
2697 see the "Tasking Support when using the Ravenscar Profile" section
2698 in the GDB user manual.
2700 * Guile support was removed.
2702 * New features in the GNU simulator
2704 ** The --map-info flag lists all known core mappings.
2706 ** CFI flashes may be simulated via the "cfi" device.
2708 *** Changes in GDB 7.2
2710 * Shared library support for remote targets by default
2712 When GDB is configured for a generic, non-OS specific target, like
2713 for example, --target=arm-eabi or one of the many *-*-elf targets,
2714 GDB now queries remote stubs for loaded shared libraries using the
2715 `qXfer:libraries:read' packet. Previously, shared library support
2716 was always disabled for such configurations.
2720 ** Argument Dependent Lookup (ADL)
2722 In C++ ADL lookup directs function search to the namespaces of its
2723 arguments even if the namespace has not been imported.
2733 Here the compiler will search for `foo' in the namespace of 'b'
2734 and find A::foo. GDB now supports this. This construct is commonly
2735 used in the Standard Template Library for operators.
2737 ** Improved User Defined Operator Support
2739 In addition to member operators, GDB now supports lookup of operators
2740 defined in a namespace and imported with a `using' directive, operators
2741 defined in the global scope, operators imported implicitly from an
2742 anonymous namespace, and the ADL operators mentioned in the previous
2744 GDB now also supports proper overload resolution for all the previously
2745 mentioned flavors of operators.
2747 ** static const class members
2749 Printing of static const class members that are initialized in the
2750 class definition has been fixed.
2752 * Windows Thread Information Block access.
2754 On Windows targets, GDB now supports displaying the Windows Thread
2755 Information Block (TIB) structure. This structure is visible either
2756 by using the new command `info w32 thread-information-block' or, by
2757 dereferencing the new convenience variable named `$_tlb', a
2758 thread-specific pointer to the TIB. This feature is also supported
2759 when remote debugging using GDBserver.
2761 * Static tracepoints
2763 Static tracepoints are calls in the user program into a tracing
2764 library. One such library is a port of the LTTng kernel tracer to
2765 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2766 When debugging with GDBserver, GDB now supports combining the GDB
2767 tracepoint machinery with such libraries. For example: the user can
2768 use GDB to probe a static tracepoint marker (a call from the user
2769 program into the tracing library) with the new "strace" command (see
2770 "New commands" below). This creates a "static tracepoint" in the
2771 breakpoint list, that can be manipulated with the same feature set
2772 as fast and regular tracepoints. E.g., collect registers, local and
2773 global variables, collect trace state variables, and define
2774 tracepoint conditions. In addition, the user can collect extra
2775 static tracepoint marker specific data, by collecting the new
2776 $_sdata internal variable. When analyzing the trace buffer, you can
2777 inspect $_sdata like any other variable available to GDB. For more
2778 information, see the "Tracepoints" chapter in GDB user manual. New
2779 remote packets have been defined to support static tracepoints, see
2780 the "New remote packets" section below.
2782 * Better reconstruction of tracepoints after disconnected tracing
2784 GDB will attempt to download the original source form of tracepoint
2785 definitions when starting a trace run, and then will upload these
2786 upon reconnection to the target, resulting in a more accurate
2787 reconstruction of the tracepoints that are in use on the target.
2791 You can now exercise direct control over the ways that GDB can
2792 affect your program. For instance, you can disallow the setting of
2793 breakpoints, so that the program can run continuously (assuming
2794 non-stop mode). In addition, the "observer" variable is available
2795 to switch all of the different controls; in observer mode, GDB
2796 cannot affect the target's behavior at all, which is useful for
2797 tasks like diagnosing live systems in the field.
2799 * The new convenience variable $_thread holds the number of the
2802 * New remote packets
2806 Return the address of the Windows Thread Information Block of a given thread.
2810 In response to several of the tracepoint packets, the target may now
2811 also respond with a number of intermediate `qRelocInsn' request
2812 packets before the final result packet, to have GDB handle
2813 relocating an instruction to execute at a different address. This
2814 is particularly useful for stubs that support fast tracepoints. GDB
2815 reports support for this feature in the qSupported packet.
2819 List static tracepoint markers in the target program.
2823 List static tracepoint markers at a given address in the target
2826 qXfer:statictrace:read
2828 Read the static trace data collected (by a `collect $_sdata'
2829 tracepoint action). The remote stub reports support for this packet
2830 to gdb's qSupported query.
2834 Send the current settings of GDB's permission flags.
2838 Send part of the source (textual) form of a tracepoint definition,
2839 which includes location, conditional, and action list.
2841 * The source command now accepts a -s option to force searching for the
2842 script in the source search path even if the script name specifies
2845 * New features in the GDB remote stub, GDBserver
2847 - GDBserver now support tracepoints (including fast tracepoints, and
2848 static tracepoints). The feature is currently supported by the
2849 i386-linux and amd64-linux builds. See the "Tracepoints support
2850 in gdbserver" section in the manual for more information.
2852 GDBserver JIT compiles the tracepoint's conditional agent
2853 expression bytecode into native code whenever possible for low
2854 overhead dynamic tracepoints conditionals. For such tracepoints,
2855 an expression that examines program state is evaluated when the
2856 tracepoint is reached, in order to determine whether to capture
2857 trace data. If the condition is simple and false, processing the
2858 tracepoint finishes very quickly and no data is gathered.
2860 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2861 for static tracepoints support.
2863 - GDBserver now supports x86_64 Windows 64-bit debugging.
2865 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2866 it understands register description.
2868 * The --batch flag now disables pagination and queries.
2870 * X86 general purpose registers
2872 GDB now supports reading/writing byte, word and double-word x86
2873 general purpose registers directly. This means you can use, say,
2874 $ah or $ax to refer, respectively, to the byte register AH and
2875 16-bit word register AX that are actually portions of the 32-bit
2876 register EAX or 64-bit register RAX.
2878 * The `commands' command now accepts a range of breakpoints to modify.
2879 A plain `commands' following a command that creates multiple
2880 breakpoints affects all the breakpoints set by that command. This
2881 applies to breakpoints set by `rbreak', and also applies when a
2882 single `break' command creates multiple breakpoints (e.g.,
2883 breakpoints on overloaded c++ functions).
2885 * The `rbreak' command now accepts a filename specification as part of
2886 its argument, limiting the functions selected by the regex to those
2887 in the specified file.
2889 * Support for remote debugging Windows and SymbianOS shared libraries
2890 from Unix hosts has been improved. Non Windows GDB builds now can
2891 understand target reported file names that follow MS-DOS based file
2892 system semantics, such as file names that include drive letters and
2893 use the backslash character as directory separator. This makes it
2894 possible to transparently use the "set sysroot" and "set
2895 solib-search-path" on Unix hosts to point as host copies of the
2896 target's shared libraries. See the new command "set
2897 target-file-system-kind" described below, and the "Commands to
2898 specify files" section in the user manual for more information.
2902 eval template, expressions...
2903 Convert the values of one or more expressions under the control
2904 of the string template to a command line, and call it.
2906 set target-file-system-kind unix|dos-based|auto
2907 show target-file-system-kind
2908 Set or show the assumed file system kind for target reported file
2911 save breakpoints <filename>
2912 Save all current breakpoint definitions to a file suitable for use
2913 in a later debugging session. To read the saved breakpoint
2914 definitions, use the `source' command.
2916 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2919 info static-tracepoint-markers
2920 Display information about static tracepoint markers in the target.
2922 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2923 Define a static tracepoint by probing a marker at the given
2924 function, line, address, or marker ID.
2928 Enable and disable observer mode.
2930 set may-write-registers on|off
2931 set may-write-memory on|off
2932 set may-insert-breakpoints on|off
2933 set may-insert-tracepoints on|off
2934 set may-insert-fast-tracepoints on|off
2935 set may-interrupt on|off
2936 Set individual permissions for GDB effects on the target. Note that
2937 some of these settings can have undesirable or surprising
2938 consequences, particularly when changed in the middle of a session.
2939 For instance, disabling the writing of memory can prevent
2940 breakpoints from being inserted, cause single-stepping to fail, or
2941 even crash your program, if you disable after breakpoints have been
2942 inserted. However, GDB should not crash.
2944 set record memory-query on|off
2945 show record memory-query
2946 Control whether to stop the inferior if memory changes caused
2947 by an instruction cannot be recorded.
2952 The disassemble command now supports "start,+length" form of two arguments.
2956 ** GDB now provides a new directory location, called the python directory,
2957 where Python scripts written for GDB can be installed. The location
2958 of that directory is <data-directory>/python, where <data-directory>
2959 is the GDB data directory. For more details, see section `Scripting
2960 GDB using Python' in the manual.
2962 ** The GDB Python API now has access to breakpoints, symbols, symbol
2963 tables, program spaces, inferiors, threads and frame's code blocks.
2964 Additionally, GDB Parameters can now be created from the API, and
2965 manipulated via set/show in the CLI.
2967 ** New functions gdb.target_charset, gdb.target_wide_charset,
2968 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2970 ** New exception gdb.GdbError.
2972 ** Pretty-printers are now also looked up in the current program space.
2974 ** Pretty-printers can now be individually enabled and disabled.
2976 ** GDB now looks for names of Python scripts to auto-load in a
2977 special section named `.debug_gdb_scripts', in addition to looking
2978 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2980 * Tracepoint actions were unified with breakpoint commands. In particular,
2981 there are no longer differences in "info break" output for breakpoints and
2982 tracepoints and the "commands" command can be used for both tracepoints and
2983 regular breakpoints.
2987 ARM Symbian arm*-*-symbianelf*
2989 * D language support.
2990 GDB now supports debugging programs written in the D programming
2993 * GDB now supports the extended ptrace interface for PowerPC which is
2994 available since Linux kernel version 2.6.34. This automatically enables
2995 any hardware breakpoints and additional hardware watchpoints available in
2996 the processor. The old ptrace interface exposes just one hardware
2997 watchpoint and no hardware breakpoints.
2999 * GDB is now able to use the Data Value Compare (DVC) register available on
3000 embedded PowerPC processors to implement in hardware simple watchpoint
3001 conditions of the form:
3003 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
3005 This works in native GDB running on Linux kernels with the extended ptrace
3006 interface mentioned above.
3008 *** Changes in GDB 7.1
3012 ** Namespace Support
3014 GDB now supports importing of namespaces in C++. This enables the
3015 user to inspect variables from imported namespaces. Support for
3016 namepace aliasing has also been added. So, if a namespace is
3017 aliased in the current scope (e.g. namepace C=A; ) the user can
3018 print variables using the alias (e.g. (gdb) print C::x).
3022 All known bugs relating to the printing of virtual base class were
3023 fixed. It is now possible to call overloaded static methods using a
3028 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
3029 and reinterpret_cast<> are now handled by the C++ expression parser.
3033 Xilinx MicroBlaze microblaze-*-*
3038 Xilinx MicroBlaze microblaze
3041 * Multi-program debugging.
3043 GDB now has support for multi-program (a.k.a. multi-executable or
3044 multi-exec) debugging. This allows for debugging multiple inferiors
3045 simultaneously each running a different program under the same GDB
3046 session. See "Debugging Multiple Inferiors and Programs" in the
3047 manual for more information. This implied some user visible changes
3048 in the multi-inferior support. For example, "info inferiors" now
3049 lists inferiors that are not running yet or that have exited
3050 already. See also "New commands" and "New options" below.
3052 * New tracing features
3054 GDB's tracepoint facility now includes several new features:
3056 ** Trace state variables
3058 GDB tracepoints now include support for trace state variables, which
3059 are variables managed by the target agent during a tracing
3060 experiment. They are useful for tracepoints that trigger each
3061 other, so for instance one tracepoint can count hits in a variable,
3062 and then a second tracepoint has a condition that is true when the
3063 count reaches a particular value. Trace state variables share the
3064 $-syntax of GDB convenience variables, and can appear in both
3065 tracepoint actions and condition expressions. Use the "tvariable"
3066 command to create, and "info tvariables" to view; see "Trace State
3067 Variables" in the manual for more detail.
3071 GDB now includes an option for defining fast tracepoints, which
3072 targets may implement more efficiently, such as by installing a jump
3073 into the target agent rather than a trap instruction. The resulting
3074 speedup can be by two orders of magnitude or more, although the
3075 tradeoff is that some program locations on some target architectures
3076 might not allow fast tracepoint installation, for instance if the
3077 instruction to be replaced is shorter than the jump. To request a
3078 fast tracepoint, use the "ftrace" command, with syntax identical to
3079 the regular trace command.
3081 ** Disconnected tracing
3083 It is now possible to detach GDB from the target while it is running
3084 a trace experiment, then reconnect later to see how the experiment
3085 is going. In addition, a new variable disconnected-tracing lets you
3086 tell the target agent whether to continue running a trace if the
3087 connection is lost unexpectedly.
3091 GDB now has the ability to save the trace buffer into a file, and
3092 then use that file as a target, similarly to you can do with
3093 corefiles. You can select trace frames, print data that was
3094 collected in them, and use tstatus to display the state of the
3095 tracing run at the moment that it was saved. To create a trace
3096 file, use "tsave <filename>", and to use it, do "target tfile
3099 ** Circular trace buffer
3101 You can ask the target agent to handle the trace buffer as a
3102 circular buffer, discarding the oldest trace frames to make room for
3103 newer ones, by setting circular-trace-buffer to on. This feature may
3104 not be available for all target agents.
3109 The disassemble command, when invoked with two arguments, now requires
3110 the arguments to be comma-separated.
3113 The info variables command now displays variable definitions. Files
3114 which only declare a variable are not shown.
3117 The source command is now capable of sourcing Python scripts.
3118 This feature is dependent on the debugger being build with Python
3121 Related to this enhancement is also the introduction of a new command
3122 "set script-extension" (see below).
3124 * New commands (for set/show, see "New options" below)
3126 record save [<FILENAME>]
3127 Save a file (in core file format) containing the process record
3128 execution log for replay debugging at a later time.
3130 record restore <FILENAME>
3131 Restore the process record execution log that was saved at an
3132 earlier time, for replay debugging.
3134 add-inferior [-copies <N>] [-exec <FILENAME>]
3137 clone-inferior [-copies <N>] [ID]
3138 Make a new inferior ready to execute the same program another
3139 inferior has loaded.
3144 maint info program-spaces
3145 List the program spaces loaded into GDB.
3147 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
3148 show remote interrupt-sequence
3149 Allow the user to select one of ^C, a BREAK signal or BREAK-g
3150 as the sequence to the remote target in order to interrupt the execution.
3151 Ctrl-C is a default. Some system prefers BREAK which is high level of
3152 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
3153 Magic SysRq g. It is BREAK signal and character 'g'.
3155 set remote interrupt-on-connect [on | off]
3156 show remote interrupt-on-connect
3157 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
3158 remote target when gdb connects to it. This is needed when you debug
3161 set remotebreak [on | off]
3163 Deprecated. Use "set/show remote interrupt-sequence" instead.
3165 tvariable $NAME [ = EXP ]
3166 Create or modify a trace state variable.
3169 List trace state variables and their values.
3171 delete tvariable $NAME ...
3172 Delete one or more trace state variables.
3175 Evaluate the given expressions without collecting anything into the
3176 trace buffer. (Valid in tracepoint actions only.)
3178 ftrace FN / FILE:LINE / *ADDR
3179 Define a fast tracepoint at the given function, line, or address.
3181 * New expression syntax
3183 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
3184 GDB now parses 0b101010 identically with 42.
3188 set follow-exec-mode new|same
3189 show follow-exec-mode
3190 Control whether GDB reuses the same inferior across an exec call or
3191 creates a new one. This is useful to be able to restart the old
3192 executable after the inferior having done an exec call.
3194 set default-collect EXPR, ...
3195 show default-collect
3196 Define a list of expressions to be collected at each tracepoint.
3197 This is a useful way to ensure essential items are not overlooked,
3198 such as registers or a critical global variable.
3200 set disconnected-tracing
3201 show disconnected-tracing
3202 If set to 1, the target is instructed to continue tracing if it
3203 loses its connection to GDB. If 0, the target is to stop tracing
3206 set circular-trace-buffer
3207 show circular-trace-buffer
3208 If set to on, the target is instructed to use a circular trace buffer
3209 and discard the oldest trace frames instead of stopping the trace due
3210 to a full trace buffer. If set to off, the trace stops when the buffer
3211 fills up. Some targets may not support this.
3213 set script-extension off|soft|strict
3214 show script-extension
3215 If set to "off", the debugger does not perform any script language
3216 recognition, and all sourced files are assumed to be GDB scripts.
3217 If set to "soft" (the default), files are sourced according to
3218 filename extension, falling back to GDB scripts if the first
3220 If set to "strict", files are sourced according to filename extension.
3222 set ada trust-PAD-over-XVS on|off
3223 show ada trust-PAD-over-XVS
3224 If off, activate a workaround against a bug in the debugging information
3225 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
3226 the GCC sources for more information about the GNAT encoding and
3227 PAD types in particular). It is always safe to set this option to
3228 off, but this introduces a slight performance penalty. The default
3231 * Python API Improvements
3233 ** GDB provides the new class gdb.LazyString. This is useful in
3234 some pretty-printing cases. The new method gdb.Value.lazy_string
3235 provides a simple way to create objects of this type.
3237 ** The fields returned by gdb.Type.fields now have an
3238 `is_base_class' attribute.
3240 ** The new method gdb.Type.range returns the range of an array type.
3242 ** The new method gdb.parse_and_eval can be used to parse and
3243 evaluate an expression.
3245 * New remote packets
3248 Define a trace state variable.
3251 Get the current value of a trace state variable.
3254 Set desired tracing behavior upon disconnection.
3257 Set the trace buffer to be linear or circular.
3260 Get data about the tracepoints currently in use.
3264 Process record now works correctly with hardware watchpoints.
3266 Multiple bug fixes have been made to the mips-irix port, making it
3267 much more reliable. In particular:
3268 - Debugging threaded applications is now possible again. Previously,
3269 GDB would hang while starting the program, or while waiting for
3270 the program to stop at a breakpoint.
3271 - Attaching to a running process no longer hangs.
3272 - An error occurring while loading a core file has been fixed.
3273 - Changing the value of the PC register now works again. This fixes
3274 problems observed when using the "jump" command, or when calling
3275 a function from GDB, or even when assigning a new value to $pc.
3276 - With the "finish" and "return" commands, the return value for functions
3277 returning a small array is now correctly printed.
3278 - It is now possible to break on shared library code which gets executed
3279 during a shared library init phase (code executed while executing
3280 their .init section). Previously, the breakpoint would have no effect.
3281 - GDB is now able to backtrace through the signal handler for
3282 non-threaded programs.
3284 PIE (Position Independent Executable) programs debugging is now supported.
3285 This includes debugging execution of PIC (Position Independent Code) shared
3286 libraries although for that, it should be possible to run such libraries as an
3289 *** Changes in GDB 7.0
3291 * GDB now has an interface for JIT compilation. Applications that
3292 dynamically generate code can create symbol files in memory and register
3293 them with GDB. For users, the feature should work transparently, and
3294 for JIT developers, the interface is documented in the GDB manual in the
3295 "JIT Compilation Interface" chapter.
3297 * Tracepoints may now be conditional. The syntax is as for
3298 breakpoints; either an "if" clause appended to the "trace" command,
3299 or the "condition" command is available. GDB sends the condition to
3300 the target for evaluation using the same bytecode format as is used
3301 for tracepoint actions.
3303 * The disassemble command now supports: an optional /r modifier, print the
3304 raw instructions in hex as well as in symbolic form, and an optional /m
3305 modifier to print mixed source+assembly.
3307 * Process record and replay
3309 In a architecture environment that supports ``process record and
3310 replay'', ``process record and replay'' target can record a log of
3311 the process execution, and replay it with both forward and reverse
3314 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3315 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3316 set execution-direction {forward|reverse}, for targets that support
3319 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3320 feature is available with a native GDB running on kernel version
3323 * GDB now has support for multi-byte and wide character sets on the
3324 target. Strings whose character type is wchar_t, char16_t, or
3325 char32_t are now correctly printed. GDB supports wide- and unicode-
3326 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3327 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3328 `printf'. This feature requires iconv to work properly; if your
3329 system does not have a working iconv, GDB can use GNU libiconv. See
3330 the installation instructions for more information.
3332 * GDB now supports automatic retrieval of shared library files from
3333 remote targets. To use this feature, specify a system root that begins
3334 with the `remote:' prefix, either via the `set sysroot' command or via
3335 the `--with-sysroot' configure-time option.
3337 * "info sharedlibrary" now takes an optional regex of libraries to show,
3338 and it now reports if a shared library has no debugging information.
3340 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3341 now complete on file names.
3343 * When completing in expressions, gdb will attempt to limit
3344 completions to allowable structure or union fields, where appropriate.
3345 For instance, consider:
3347 # struct example { int f1; double f2; };
3348 # struct example variable;
3351 If the user types TAB at the end of this command line, the available
3352 completions will be "f1" and "f2".
3354 * Inlined functions are now supported. They show up in backtraces, and
3355 the "step", "next", and "finish" commands handle them automatically.
3357 * GDB now supports the token-splicing (##) and stringification (#)
3358 operators when expanding macros. It also supports variable-arity
3361 * GDB now supports inspecting extra signal information, exported by
3362 the new $_siginfo convenience variable. The feature is currently
3363 implemented on linux ARM, i386 and amd64.
3365 * GDB can now display the VFP floating point registers and NEON vector
3366 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3367 can provide these registers (requires Linux 2.6.30 or later). Remote
3368 and simulator targets may also provide them.
3370 * New remote packets
3373 Search memory for a sequence of bytes.
3376 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3377 operation over reliable transport links. Use of this packet is
3378 controlled by the `set remote noack-packet' command.
3381 Kill the process with the specified process ID. Use this in preference
3382 to `k' when multiprocess protocol extensions are supported.
3385 Obtains additional operating system information
3389 Read or write additional signal information.
3391 * Removed remote protocol undocumented extension
3393 An undocumented extension to the remote protocol's `S' stop reply
3394 packet that permited the stub to pass a process id was removed.
3395 Remote servers should use the `T' stop reply packet instead.
3397 * GDB now supports multiple function calling conventions according to the
3398 DWARF-2 DW_AT_calling_convention function attribute.
3400 * The SH target utilizes the aforementioned change to distinguish between gcc
3401 and Renesas calling convention. It also adds the new CLI commands
3402 `set/show sh calling-convention'.
3404 * GDB can now read compressed debug sections, as produced by GNU gold
3405 with the --compress-debug-sections=zlib flag.
3407 * 64-bit core files are now supported on AIX.
3409 * Thread switching is now supported on Tru64.
3411 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3412 which will be allocated using malloc later in program execution.
3414 * The qXfer:libraries:read remote procotol packet now allows passing a
3415 list of section offsets.
3417 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3418 conditions handling signals delivered during attach or thread creation
3419 have also been fixed.
3421 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3422 From the user's standpoint, all unqualified instances of True and False
3423 are treated as the standard definitions, regardless of context.
3425 * GDB now parses C++ symbol and type names more flexibly. For
3428 template<typename T> class C { };
3431 GDB will now correctly handle all of:
3433 ptype C<char const *>
3434 ptype C<char const*>
3435 ptype C<const char *>
3436 ptype C<const char*>
3438 * New features in the GDB remote stub, gdbserver
3440 - The "--wrapper" command-line argument tells gdbserver to use a
3441 wrapper program to launch programs for debugging.
3443 - On PowerPC and S/390 targets, it is now possible to use a single
3444 gdbserver executable to debug both 32-bit and 64-bit programs.
3445 (This requires gdbserver itself to be built as a 64-bit executable.)
3447 - gdbserver uses the new noack protocol mode for TCP connections to
3448 reduce communications latency, if also supported and enabled in GDB.
3450 - Support for the sparc64-linux-gnu target is now included in
3453 - The amd64-linux build of gdbserver now supports debugging both
3454 32-bit and 64-bit programs.
3456 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3457 now support hardware watchpoints, and will use them automatically
3462 GDB now has support for scripting using Python. Whether this is
3463 available is determined at configure time.
3465 New GDB commands can now be written in Python.
3467 * Ada tasking support
3469 Ada tasks can now be inspected in GDB. The following commands have
3473 Print the list of Ada tasks.
3475 Print detailed information about task number N.
3477 Print the task number of the current task.
3479 Switch the context of debugging to task number N.
3481 * Support for user-defined prefixed commands. The "define" command can
3482 add new commands to existing prefixes, e.g. "target".
3484 * Multi-inferior, multi-process debugging.
3486 GDB now has generalized support for multi-inferior debugging. See
3487 "Debugging Multiple Inferiors" in the manual for more information.
3488 Although availability still depends on target support, the command
3489 set is more uniform now. The GNU/Linux specific multi-forks support
3490 has been migrated to this new framework. This implied some user
3491 visible changes; see "New commands" and also "Removed commands"
3494 * Target descriptions can now describe the target OS ABI. See the
3495 "Target Description Format" section in the user manual for more
3498 * Target descriptions can now describe "compatible" architectures
3499 to indicate that the target can execute applications for a different
3500 architecture in addition to those for the main target architecture.
3501 See the "Target Description Format" section in the user manual for
3504 * Multi-architecture debugging.
3506 GDB now includes general supports for debugging applications on
3507 hybrid systems that use more than one single processor architecture
3508 at the same time. Each such hybrid architecture still requires
3509 specific support to be added. The only hybrid architecture supported
3510 in this version of GDB is the Cell Broadband Engine.
3512 * GDB now supports integrated debugging of Cell/B.E. applications that
3513 use both the PPU and SPU architectures. To enable support for hybrid
3514 Cell/B.E. debugging, you need to configure GDB to support both the
3515 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3516 --enable-targets configure option.
3518 * Non-stop mode debugging.
3520 For some targets, GDB now supports an optional mode of operation in
3521 which you can examine stopped threads while other threads continue
3522 to execute freely. This is referred to as non-stop mode, with the
3523 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3524 section in the user manual for more information.
3526 To be able to support remote non-stop debugging, a remote stub needs
3527 to implement the non-stop mode remote protocol extensions, as
3528 described in the "Remote Non-Stop" section of the user manual. The
3529 GDB remote stub, gdbserver, has been adjusted to support these
3530 extensions on linux targets.
3532 * New commands (for set/show, see "New options" below)
3534 catch syscall [NAME(S) | NUMBER(S)]
3535 Catch system calls. Arguments, which should be names of system
3536 calls or their numbers, mean catch only those syscalls. Without
3537 arguments, every syscall will be caught. When the inferior issues
3538 any of the specified syscalls, GDB will stop and announce the system
3539 call, both when it is called and when its call returns. This
3540 feature is currently available with a native GDB running on the
3541 Linux Kernel, under the following architectures: x86, x86_64,
3542 PowerPC and PowerPC64.
3544 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3546 Search memory for a sequence of bytes.
3548 maint set python print-stack
3549 maint show python print-stack
3550 Show a stack trace when an error is encountered in a Python script.
3553 Invoke CODE by passing it to the Python interpreter.
3558 These allow macros to be defined, undefined, and listed
3562 Show operating system information about processes.
3565 List the inferiors currently under GDB's control.
3568 Switch focus to inferior number NUM.
3571 Detach from inferior number NUM.
3574 Kill inferior number NUM.
3578 set spu stop-on-load
3579 show spu stop-on-load
3580 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3582 set spu auto-flush-cache
3583 show spu auto-flush-cache
3584 Control whether to automatically flush the software-managed cache
3585 during Cell/B.E. debugging.
3587 set sh calling-convention
3588 show sh calling-convention
3589 Control the calling convention used when calling SH target functions.
3592 show debug timestamp
3593 Control display of timestamps with GDB debugging output.
3595 set disassemble-next-line
3596 show disassemble-next-line
3597 Control display of disassembled source lines or instructions when
3600 set remote noack-packet
3601 show remote noack-packet
3602 Set/show the use of remote protocol QStartNoAckMode packet. See above
3603 under "New remote packets."
3605 set remote query-attached-packet
3606 show remote query-attached-packet
3607 Control use of remote protocol `qAttached' (query-attached) packet.
3609 set remote read-siginfo-object
3610 show remote read-siginfo-object
3611 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3614 set remote write-siginfo-object
3615 show remote write-siginfo-object
3616 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3619 set remote reverse-continue
3620 show remote reverse-continue
3621 Control use of remote protocol 'bc' (reverse-continue) packet.
3623 set remote reverse-step
3624 show remote reverse-step
3625 Control use of remote protocol 'bs' (reverse-step) packet.
3627 set displaced-stepping
3628 show displaced-stepping
3629 Control displaced stepping mode. Displaced stepping is a way to
3630 single-step over breakpoints without removing them from the debuggee.
3631 Also known as "out-of-line single-stepping".
3634 show debug displaced
3635 Control display of debugging info for displaced stepping.
3637 maint set internal-error
3638 maint show internal-error
3639 Control what GDB does when an internal error is detected.
3641 maint set internal-warning
3642 maint show internal-warning
3643 Control what GDB does when an internal warning is detected.
3648 Use a wrapper program to launch programs for debugging.
3650 set multiple-symbols (all|ask|cancel)
3651 show multiple-symbols
3652 The value of this variable can be changed to adjust the debugger behavior
3653 when an expression or a breakpoint location contains an ambiguous symbol
3654 name (an overloaded function name, for instance).
3656 set breakpoint always-inserted
3657 show breakpoint always-inserted
3658 Keep breakpoints always inserted in the target, as opposed to inserting
3659 them when resuming the target, and removing them when the target stops.
3660 This option can improve debugger performance on slow remote targets.
3662 set arm fallback-mode (arm|thumb|auto)
3663 show arm fallback-mode
3664 set arm force-mode (arm|thumb|auto)
3666 These commands control how ARM GDB determines whether instructions
3667 are ARM or Thumb. The default for both settings is auto, which uses
3668 the current CPSR value for instructions without symbols; previous
3669 versions of GDB behaved as if "set arm fallback-mode arm".
3671 set disable-randomization
3672 show disable-randomization
3673 Standalone programs run with the virtual address space randomization enabled
3674 by default on some platforms. This option keeps the addresses stable across
3675 multiple debugging sessions.
3679 Control whether other threads are stopped or not when some thread hits
3684 Requests that asynchronous execution is enabled in the target, if available.
3685 In this case, it's possible to resume target in the background, and interact
3686 with GDB while the target is running. "show target-async" displays the
3687 current state of asynchronous execution of the target.
3689 set target-wide-charset
3690 show target-wide-charset
3691 The target-wide-charset is the name of the character set that GDB
3692 uses when printing characters whose type is wchar_t.
3694 set tcp auto-retry (on|off)
3696 set tcp connect-timeout
3697 show tcp connect-timeout
3698 These commands allow GDB to retry failed TCP connections to a remote stub
3699 with a specified timeout period; this is useful if the stub is launched
3700 in parallel with GDB but may not be ready to accept connections immediately.
3702 set libthread-db-search-path
3703 show libthread-db-search-path
3704 Control list of directories which GDB will search for appropriate
3707 set schedule-multiple (on|off)
3708 show schedule-multiple
3709 Allow GDB to resume all threads of all processes or only threads of
3710 the current process.
3714 Use more aggressive caching for accesses to the stack. This improves
3715 performance of remote debugging (particularly backtraces) without
3716 affecting correctness.
3718 set interactive-mode (on|off|auto)
3719 show interactive-mode
3720 Control whether GDB runs in interactive mode (on) or not (off).
3721 When in interactive mode, GDB waits for the user to answer all
3722 queries. Otherwise, GDB does not wait and assumes the default
3723 answer. When set to auto (the default), GDB determines which
3724 mode to use based on the stdin settings.
3729 For program forks, this is replaced by the new more generic `info
3730 inferiors' command. To list checkpoints, you can still use the
3731 `info checkpoints' command, which was an alias for the `info forks'
3735 Replaced by the new `inferior' command. To switch between
3736 checkpoints, you can still use the `restart' command, which was an
3737 alias for the `fork' command.
3740 This is removed, since some targets don't have a notion of
3741 processes. To switch between processes, you can still use the
3742 `inferior' command using GDB's own inferior number.
3745 For program forks, this is replaced by the new more generic `kill
3746 inferior' command. To delete a checkpoint, you can still use the
3747 `delete checkpoint' command, which was an alias for the `delete
3751 For program forks, this is replaced by the new more generic `detach
3752 inferior' command. To detach a checkpoint, you can still use the
3753 `detach checkpoint' command, which was an alias for the `detach
3756 * New native configurations
3758 x86/x86_64 Darwin i[34567]86-*-darwin*
3760 x86_64 MinGW x86_64-*-mingw*
3764 Lattice Mico32 lm32-*
3765 x86 DICOS i[34567]86-*-dicos*
3766 x86_64 DICOS x86_64-*-dicos*
3769 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3770 (mingw32ce) debugging.
3776 These commands were actually not implemented on any target.
3778 *** Changes in GDB 6.8
3780 * New native configurations
3782 NetBSD/hppa hppa*-*netbsd*
3783 Xtensa GNU/Linux xtensa*-*-linux*
3787 NetBSD/hppa hppa*-*-netbsd*
3788 Xtensa GNU/Lunux xtensa*-*-linux*
3790 * Change in command line behavior -- corefiles vs. process ids.
3792 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3793 attaching to process NUMBER fails, GDB no longer attempts to open a
3794 core file named NUMBER. Attaching to a program using the -c option
3795 is no longer supported. Instead, use the '-p' or '--pid' options.
3797 * GDB can now be built as a native debugger for debugging Windows x86
3798 (mingw32) Portable Executable (PE) programs.
3800 * Pending breakpoints no longer change their number when their address
3803 * GDB now supports breakpoints with multiple locations,
3804 including breakpoints on C++ constructors, inside C++ templates,
3805 and in inlined functions.
3807 * GDB's ability to debug optimized code has been improved. GDB more
3808 accurately identifies function bodies and lexical blocks that occupy
3809 more than one contiguous range of addresses.
3811 * Target descriptions can now describe registers for PowerPC.
3813 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3814 registers on PowerPC targets.
3816 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3817 targets even when the libthread_db library is not available.
3819 * The GDB remote stub, gdbserver, now supports the new file transfer
3820 commands (remote put, remote get, and remote delete).
3822 * The GDB remote stub, gdbserver, now supports run and attach in
3823 extended-remote mode.
3825 * hppa*64*-*-hpux11* target broken
3826 The debugger is unable to start a program and fails with the following
3827 error: "Error trying to get information about dynamic linker".
3828 The gdb-6.7 release is also affected.
3830 * GDB now supports the --enable-targets= configure option to allow
3831 building a single GDB executable that supports multiple remote
3832 target architectures.
3834 * GDB now supports debugging C and C++ programs which use the
3835 Decimal Floating Point extension. In addition, the PowerPC target
3836 now has a set of pseudo-registers to inspect decimal float values
3837 stored in two consecutive float registers.
3839 * The -break-insert MI command can optionally create pending
3842 * Improved support for debugging Ada
3843 Many improvements to the Ada language support have been made. These
3845 - Better support for Ada2005 interface types
3846 - Improved handling of arrays and slices in general
3847 - Better support for Taft-amendment types
3848 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3850 - Improved command completion in Ada
3853 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3858 set print frame-arguments (all|scalars|none)
3859 show print frame-arguments
3860 The value of this variable can be changed to control which argument
3861 values should be printed by the debugger when displaying a frame.
3866 Transfer files to and from a remote target, and delete remote files.
3873 Transfer files to and from a remote target, and delete remote files.
3875 * New remote packets
3882 Open, close, read, write, and delete files on the remote system.
3885 Attach to an existing process on the remote system, in extended-remote
3889 Run a new process on the remote system, in extended-remote mode.
3891 *** Changes in GDB 6.7
3893 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3894 bfd, libiberty and opcodes, as revealed by static analysis donated by
3895 Coverity, Inc. (http://scan.coverity.com).
3897 * When looking up multiply-defined global symbols, GDB will now prefer the
3898 symbol definition in the current shared library if it was built using the
3899 -Bsymbolic linker option.
3901 * When the Text User Interface (TUI) is not configured, GDB will now
3902 recognize the -tui command-line option and print a message that the TUI
3905 * The GDB remote stub, gdbserver, now has lower overhead for high
3906 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3908 * GDB for MIPS targets now autodetects whether a remote target provides
3909 32-bit or 64-bit register values.
3911 * Support for C++ member pointers has been improved.
3913 * GDB now understands XML target descriptions, which specify the
3914 target's overall architecture. GDB can read a description from
3915 a local file or over the remote serial protocol.
3917 * Vectors of single-byte data use a new integer type which is not
3918 automatically displayed as character or string data.
3920 * The /s format now works with the print command. It displays
3921 arrays of single-byte integers and pointers to single-byte integers
3924 * Target descriptions can now describe target-specific registers,
3925 for architectures which have implemented the support (currently
3926 only ARM, M68K, and MIPS).
3928 * GDB and the GDB remote stub, gdbserver, now support the XScale
3931 * The GDB remote stub, gdbserver, has been updated to support
3932 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3933 has been rewritten to use the standard GDB remote protocol.
3935 * GDB can now step into C++ functions which are called through thunks.
3937 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3939 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3940 layout. It also supports a TextSeg= and DataSeg= response when only
3941 segment base addresses (rather than offsets) are available.
3943 * The /i format now outputs any trailing branch delay slot instructions
3944 immediately following the last instruction within the count specified.
3946 * The GDB remote protocol "T" stop reply packet now supports a
3947 "library" response. Combined with the new "qXfer:libraries:read"
3948 packet, this response allows GDB to debug shared libraries on targets
3949 where the operating system manages the list of loaded libraries (e.g.
3950 Windows and SymbianOS).
3952 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3953 (DLLs) on Windows and Windows CE targets.
3955 * GDB now supports a faster verification that a .debug file matches its binary
3956 according to its build-id signature, if the signature is present.
3962 Enable or disable hardware flow control (RTS/CTS) on the serial port
3963 when debugging using remote targets.
3965 set mem inaccessible-by-default
3966 show mem inaccessible-by-default
3967 If the target supplies a memory map, for instance via the remote
3968 protocol's "qXfer:memory-map:read" packet, setting this variable
3969 prevents GDB from accessing memory outside the memory map. This
3970 is useful for targets with memory mapped registers or which react
3971 badly to accesses of unmapped address space.
3973 set breakpoint auto-hw
3974 show breakpoint auto-hw
3975 If the target supplies a memory map, for instance via the remote
3976 protocol's "qXfer:memory-map:read" packet, setting this variable
3977 lets GDB use hardware breakpoints automatically for memory regions
3978 where it can not use software breakpoints. This covers both the
3979 "break" command and internal breakpoints used for other commands
3980 including "next" and "finish".
3983 catch exception unhandled
3984 Stop the program execution when Ada exceptions are raised.
3987 Stop the program execution when an Ada assertion failed.
3991 Set an alternate system root for target files. This is a more
3992 general version of "set solib-absolute-prefix", which is now
3993 an alias to "set sysroot".
3996 Provide extended SPU facility status information. This set of
3997 commands is available only when debugging the Cell/B.E. SPU
4000 * New native configurations
4002 OpenBSD/sh sh*-*openbsd*
4005 unset tdesc filename
4007 Use the specified local file as an XML target description, and do
4008 not query the target for its built-in description.
4012 OpenBSD/sh sh*-*-openbsd*
4013 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
4014 Toshiba Media Processor mep-elf
4016 * New remote packets
4019 Ignore the specified signals; pass them directly to the debugged program
4020 without stopping other threads or reporting them to GDB.
4022 qXfer:features:read:
4023 Read an XML target description from the target, which describes its
4028 Read or write contents of an spufs file on the target system. These
4029 packets are available only on the Cell/B.E. SPU architecture.
4031 qXfer:libraries:read:
4032 Report the loaded shared libraries. Combined with new "T" packet
4033 response, this packet allows GDB to debug shared libraries on
4034 targets where the operating system manages the list of loaded
4035 libraries (e.g. Windows and SymbianOS).
4039 Support for these obsolete configurations has been removed.
4047 i[34567]86-*-lynxos*
4048 i[34567]86-*-netware*
4049 i[34567]86-*-sco3.2v5*
4050 i[34567]86-*-sco3.2v4*
4052 i[34567]86-*-sysv4.2*
4055 i[34567]86-*-unixware2*
4056 i[34567]86-*-unixware*
4065 * Other removed features
4072 Various m68k-only ROM monitors.
4079 Various Renesas ROM monitors and debugging interfaces for SH and
4084 Support for a Macraigor serial interface to on-chip debugging.
4085 GDB does not directly support the newer parallel or USB
4090 A debug information format. The predecessor to DWARF 2 and
4091 DWARF 3, which are still supported.
4093 Support for the HP aCC compiler on HP-UX/PA-RISC
4095 SOM-encapsulated symbolic debugging information, automatic
4096 invocation of pxdb, and the aCC custom C++ ABI. This does not
4097 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
4098 with aCC can still be debugged on an assembly level.
4100 MIPS ".pdr" sections
4102 A MIPS-specific format used to describe stack frame layout
4103 in debugging information.
4107 GDB could work with an older version of Guile to debug
4108 the interpreter and Scheme programs running in it.
4110 set mips stack-arg-size
4111 set mips saved-gpreg-size
4113 Use "set mips abi" to control parameter passing for MIPS.
4115 *** Changes in GDB 6.6
4120 Cell Broadband Engine SPU spu-elf
4122 * GDB can now be configured as a cross-debugger targeting native Windows
4123 (mingw32) or Cygwin. It can communicate with a remote debugging stub
4124 running on a Windows system over TCP/IP to debug Windows programs.
4126 * The GDB remote stub, gdbserver, has been updated to support Windows and
4127 Cygwin debugging. Both single-threaded and multi-threaded programs are
4130 * The "set trust-readonly-sections" command works again. This command was
4131 broken in GDB 6.3, 6.4, and 6.5.
4133 * The "load" command now supports writing to flash memory, if the remote
4134 stub provides the required support.
4136 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
4137 longer requires symbolic debug information (e.g. DWARF-2).
4142 unset substitute-path
4143 show substitute-path
4144 Manage a list of substitution rules that GDB uses to rewrite the name
4145 of the directories where the sources are located. This can be useful
4146 for instance when the sources were moved to a different location
4147 between compilation and debugging.
4151 Print each CLI command as it is executed. Each command is prefixed with
4152 a number of `+' symbols representing the nesting depth.
4153 The source command now has a `-v' option to enable the same feature.
4157 The ARM Demon monitor support (RDP protocol, "target rdp").
4159 Kernel Object Display, an embedded debugging feature which only worked with
4160 an obsolete version of Cisco IOS.
4162 The 'set download-write-size' and 'show download-write-size' commands.
4164 * New remote packets
4167 Tell a stub about GDB client features, and request remote target features.
4168 The first feature implemented is PacketSize, which allows the target to
4169 specify the size of packets it can handle - to minimize the number of
4170 packets required and improve performance when connected to a remote
4174 Fetch an OS auxilliary vector from the remote stub. This packet is a
4175 more efficient replacement for qPart:auxv:read.
4177 qXfer:memory-map:read:
4178 Fetch a memory map from the remote stub, including information about
4179 RAM, ROM, and flash memory devices.
4184 Erase and program a flash memory device.
4186 * Removed remote packets
4189 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
4190 used it, and only gdbserver implemented it.
4192 *** Changes in GDB 6.5
4196 Renesas M32C/M16C m32c-elf
4198 Morpho Technologies ms1 ms1-elf
4202 init-if-undefined Initialize a convenience variable, but
4203 only if it doesn't already have a value.
4205 The following commands are presently only implemented for native GNU/Linux:
4207 checkpoint Save a snapshot of the program state.
4209 restart <n> Return the program state to a
4210 previously saved state.
4212 info checkpoints List currently saved checkpoints.
4214 delete-checkpoint <n> Delete a previously saved checkpoint.
4216 set|show detach-on-fork Tell gdb whether to detach from a newly
4217 forked process, or to keep debugging it.
4219 info forks List forks of the user program that
4220 are available to be debugged.
4222 fork <n> Switch to debugging one of several
4223 forks of the user program that are
4224 available to be debugged.
4226 delete-fork <n> Delete a fork from the list of forks
4227 that are available to be debugged (and
4228 kill the forked process).
4230 detach-fork <n> Delete a fork from the list of forks
4231 that are available to be debugged (and
4232 allow the process to continue).
4236 Morpho Technologies ms2 ms1-elf
4238 * Improved Windows host support
4240 GDB now builds as a cross debugger hosted on i686-mingw32, including
4241 native console support, and remote communications using either
4242 network sockets or serial ports.
4244 * Improved Modula-2 language support
4246 GDB can now print most types in the Modula-2 syntax. This includes:
4247 basic types, set types, record types, enumerated types, range types,
4248 pointer types and ARRAY types. Procedure var parameters are correctly
4249 printed and hexadecimal addresses and character constants are also
4250 written in the Modula-2 syntax. Best results can be obtained by using
4251 GNU Modula-2 together with the -gdwarf-2 command line option.
4255 The ARM rdi-share module.
4257 The Netware NLM debug server.
4259 *** Changes in GDB 6.4
4261 * New native configurations
4263 OpenBSD/arm arm*-*-openbsd*
4264 OpenBSD/mips64 mips64-*-openbsd*
4268 Morpho Technologies ms1 ms1-elf
4270 * New command line options
4272 --batch-silent As for --batch, but totally silent.
4273 --return-child-result The debugger will exist with the same value
4274 the child (debugged) program exited with.
4275 --eval-command COMMAND, -ex COMMAND
4276 Execute a single GDB CLI command. This may be
4277 specified multiple times and in conjunction
4278 with the --command (-x) option.
4280 * Deprecated commands removed
4282 The following commands, that were deprecated in 2000, have been
4286 set|show arm disassembly-flavor set|show arm disassembler
4287 othernames set arm disassembler
4288 set|show remotedebug set|show debug remote
4289 set|show archdebug set|show debug arch
4290 set|show eventdebug set|show debug event
4293 * New BSD user-level threads support
4295 It is now possible to debug programs using the user-level threads
4296 library on OpenBSD and FreeBSD. Currently supported (target)
4299 FreeBSD/amd64 x86_64-*-freebsd*
4300 FreeBSD/i386 i386-*-freebsd*
4301 OpenBSD/i386 i386-*-openbsd*
4303 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4304 are not yet supported.
4306 * New support for Matsushita MN10300 w/sim added
4307 (Work in progress). mn10300-elf.
4309 * REMOVED configurations and files
4311 VxWorks and the XDR protocol *-*-vxworks
4312 Motorola MCORE mcore-*-*
4313 National Semiconductor NS32000 ns32k-*-*
4315 * New "set print array-indexes" command
4317 After turning this setting "on", GDB prints the index of each element
4318 when displaying arrays. The default is "off" to preserve the previous
4321 * VAX floating point support
4323 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4325 * User-defined command support
4327 In addition to using $arg0..$arg9 for argument passing, it is now possible
4328 to use $argc to determine now many arguments have been passed. See the
4329 section on user-defined commands in the user manual for more information.
4331 *** Changes in GDB 6.3:
4333 * New command line option
4335 GDB now accepts -l followed by a number to set the timeout for remote
4338 * GDB works with GCC -feliminate-dwarf2-dups
4340 GDB now supports a more compact representation of DWARF-2 debug
4341 information using DW_FORM_ref_addr references. These are produced
4342 by GCC with the option -feliminate-dwarf2-dups and also by some
4343 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4344 to use -feliminate-dwarf2-dups.
4346 * Internationalization
4348 When supported by the host system, GDB will be built with
4349 internationalization (libintl). The task of marking up the sources is
4350 continued, we're looking forward to our first translation.
4354 Initial support for debugging programs compiled with the GNAT
4355 implementation of the Ada programming language has been integrated
4356 into GDB. In this release, support is limited to expression evaluation.
4358 * New native configurations
4360 GNU/Linux/m32r m32r-*-linux-gnu
4364 GDB's remote protocol now includes support for the 'p' packet. This
4365 packet is used to fetch individual registers from a remote inferior.
4367 * END-OF-LIFE registers[] compatibility module
4369 GDB's internal register infrastructure has been completely rewritten.
4370 The new infrastructure making possible the implementation of key new
4371 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4374 GDB 6.3 will be the last release to include the the registers[]
4375 compatibility module that allowed out-of-date configurations to
4376 continue to work. This change directly impacts the following
4386 powerpc bdm protocol
4388 Unless there is activity to revive these configurations, they will be
4389 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4391 * OBSOLETE configurations and files
4393 Configurations that have been declared obsolete in this release have
4394 been commented out. Unless there is activity to revive these
4395 configurations, the next release of GDB will have their sources
4396 permanently REMOVED.
4405 *** Changes in GDB 6.2.1:
4407 * MIPS `break main; run' gave an heuristic-fence-post warning
4409 When attempting to run even a simple program, a warning about
4410 heuristic-fence-post being hit would be reported. This problem has
4413 * MIPS IRIX 'long double' crashed GDB
4415 When examining a long double variable, GDB would get a segmentation
4416 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4417 IRIX long double values).
4421 A bug in the VAX stack code was causing problems with the "next"
4422 command. This problem has been fixed.
4424 *** Changes in GDB 6.2:
4426 * Fix for ``many threads''
4428 On GNU/Linux systems that use the NPTL threads library, a program
4429 rapidly creating and deleting threads would confuse GDB leading to the
4432 ptrace: No such process.
4433 thread_db_get_info: cannot get thread info: generic error
4435 This problem has been fixed.
4437 * "-async" and "-noasync" options removed.
4439 Support for the broken "-noasync" option has been removed (it caused
4442 * New ``start'' command.
4444 This command runs the program until the begining of the main procedure.
4446 * New BSD Kernel Data Access Library (libkvm) interface
4448 Using ``target kvm'' it is now possible to debug kernel core dumps and
4449 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4450 platforms. Currently supported (native-only) configurations are:
4452 FreeBSD/amd64 x86_64-*-freebsd*
4453 FreeBSD/i386 i?86-*-freebsd*
4454 NetBSD/i386 i?86-*-netbsd*
4455 NetBSD/m68k m68*-*-netbsd*
4456 NetBSD/sparc sparc-*-netbsd*
4457 OpenBSD/amd64 x86_64-*-openbsd*
4458 OpenBSD/i386 i?86-*-openbsd*
4459 OpenBSD/m68k m68*-openbsd*
4460 OpenBSD/sparc sparc-*-openbsd*
4462 * Signal trampoline code overhauled
4464 Many generic problems with GDB's signal handling code have been fixed.
4465 These include: backtraces through non-contiguous stacks; recognition
4466 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4467 call; backtrace through a signal trampoline; step into and out of
4468 signal handlers; and single-stepping in the signal trampoline.
4470 Please note that kernel bugs are a limiting factor here. These
4471 features have been shown to work on an s390 GNU/Linux system that
4472 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4474 * Cygwin support for DWARF 2 added.
4476 * New native configurations
4478 GNU/Linux/hppa hppa*-*-linux*
4479 OpenBSD/hppa hppa*-*-openbsd*
4480 OpenBSD/m68k m68*-*-openbsd*
4481 OpenBSD/m88k m88*-*-openbsd*
4482 OpenBSD/powerpc powerpc-*-openbsd*
4483 NetBSD/vax vax-*-netbsd*
4484 OpenBSD/vax vax-*-openbsd*
4486 * END-OF-LIFE frame compatibility module
4488 GDB's internal frame infrastructure has been completely rewritten.
4489 The new infrastructure making it possible to support key new features
4490 including DWARF 2 Call Frame Information. To aid in the task of
4491 migrating old configurations to this new infrastructure, a
4492 compatibility module, that allowed old configurations to continue to
4493 work, was also included.
4495 GDB 6.2 will be the last release to include this frame compatibility
4496 module. This change directly impacts the following configurations:
4506 Unless there is activity to revive these configurations, they will be
4507 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4509 * REMOVED configurations and files
4511 Sun 3, running SunOS 3 m68*-*-sunos3*
4512 Sun 3, running SunOS 4 m68*-*-sunos4*
4513 Sun 2, running SunOS 3 m68000-*-sunos3*
4514 Sun 2, running SunOS 4 m68000-*-sunos4*
4515 Motorola 680x0 running LynxOS m68*-*-lynxos*
4516 AT&T 3b1/Unix pc m68*-att-*
4517 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4518 decstation mips-dec-* mips-little-*
4519 riscos mips-*-riscos* mips-*-sysv*
4520 sonymips mips-sony-*
4521 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4523 *** Changes in GDB 6.1.1:
4525 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4527 The TUI (Text-mode User Interface) is now built as part of a default
4528 GDB configuration. It is enabled by either selecting the TUI with the
4529 command line option "-i=tui" or by running the separate "gdbtui"
4530 program. For more information on the TUI, see the manual "Debugging
4533 * Pending breakpoint support (also included in GDB 6.1)
4535 Support has been added to allow you to specify breakpoints in shared
4536 libraries that have not yet been loaded. If a breakpoint location
4537 cannot be found, and the "breakpoint pending" option is set to auto,
4538 GDB queries you if you wish to make the breakpoint pending on a future
4539 shared-library load. If and when GDB resolves the breakpoint symbol,
4540 the pending breakpoint is removed as one or more regular breakpoints
4543 Pending breakpoints are very useful for GCJ Java debugging.
4545 * Fixed ISO-C build problems
4547 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4548 non ISO-C code that stopped them being built using a more strict ISO-C
4549 compiler (e.g., IBM's C compiler).
4551 * Fixed build problem on IRIX 5
4553 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4554 wasn't able to compile compile on an IRIX 5 system.
4556 * Added execute permission to gdb/gdbserver/configure
4558 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4559 permission. This bug would cause configure to fail on a number of
4560 systems (Solaris, IRIX). Ref: server/519.
4562 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4564 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4565 has been updated to use constant array sizes.
4567 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4569 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4570 its generated DWARF Call Frame Info. This encoding was causing GDB to
4571 panic, that panic has been fixed. Ref: gdb/1628.
4573 * Fixed a problem when examining parameters in shared library code.
4575 When examining parameters in optimized shared library code generated
4576 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4577 not available''. GDB now correctly displays the variable's value.
4579 *** Changes in GDB 6.1:
4581 * Removed --with-mmalloc
4583 Support for the mmalloc memory manager has been removed, as it
4584 conflicted with the internal gdb byte cache.
4586 * Changes in AMD64 configurations
4588 The AMD64 target now includes the %cs and %ss registers. As a result
4589 the AMD64 remote protocol has changed; this affects the floating-point
4590 and SSE registers. If you rely on those registers for your debugging,
4591 you should upgrade gdbserver on the remote side.
4593 * Revised SPARC target
4595 The SPARC target has been completely revised, incorporating the
4596 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4597 support for LynxOS and SunOS 4 has been dropped. Calling functions
4598 from within GDB on operating systems with a non-executable stack
4599 (Solaris, OpenBSD) now works.
4603 GDB has a new C++ demangler which does a better job on the mangled
4604 names generated by current versions of g++. It also runs faster, so
4605 with this and other changes gdb should now start faster on large C++
4608 * DWARF 2 Location Expressions
4610 GDB support for location expressions has been extended to support function
4611 arguments and frame bases. Older versions of GDB could crash when they
4614 * C++ nested types and namespaces
4616 GDB's support for nested types and namespaces in C++ has been
4617 improved, especially if you use the DWARF 2 debugging format. (This
4618 is the default for recent versions of GCC on most platforms.)
4619 Specifically, if you have a class "Inner" defined within a class or
4620 namespace "Outer", then GDB realizes that the class's name is
4621 "Outer::Inner", not simply "Inner". This should greatly reduce the
4622 frequency of complaints about not finding RTTI symbols. In addition,
4623 if you are stopped at inside of a function defined within a namespace,
4624 GDB modifies its name lookup accordingly.
4626 * New native configurations
4628 NetBSD/amd64 x86_64-*-netbsd*
4629 OpenBSD/amd64 x86_64-*-openbsd*
4630 OpenBSD/alpha alpha*-*-openbsd*
4631 OpenBSD/sparc sparc-*-openbsd*
4632 OpenBSD/sparc64 sparc64-*-openbsd*
4634 * New debugging protocols
4636 M32R with SDI protocol m32r-*-elf*
4638 * "set prompt-escape-char" command deleted.
4640 The command "set prompt-escape-char" has been deleted. This command,
4641 and its very obscure effet on GDB's prompt, was never documented,
4642 tested, nor mentioned in the NEWS file.
4644 * OBSOLETE configurations and files
4646 Configurations that have been declared obsolete in this release have
4647 been commented out. Unless there is activity to revive these
4648 configurations, the next release of GDB will have their sources
4649 permanently REMOVED.
4651 Sun 3, running SunOS 3 m68*-*-sunos3*
4652 Sun 3, running SunOS 4 m68*-*-sunos4*
4653 Sun 2, running SunOS 3 m68000-*-sunos3*
4654 Sun 2, running SunOS 4 m68000-*-sunos4*
4655 Motorola 680x0 running LynxOS m68*-*-lynxos*
4656 AT&T 3b1/Unix pc m68*-att-*
4657 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4658 decstation mips-dec-* mips-little-*
4659 riscos mips-*-riscos* mips-*-sysv*
4660 sonymips mips-sony-*
4661 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4663 * REMOVED configurations and files
4665 SGI Irix-4.x mips-sgi-irix4 or iris4
4666 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4667 Z8000 simulator z8k-zilog-none or z8ksim
4668 Matsushita MN10200 w/simulator mn10200-*-*
4669 H8/500 simulator h8500-hitachi-hms or h8500hms
4670 HP/PA running BSD hppa*-*-bsd*
4671 HP/PA running OSF/1 hppa*-*-osf*
4672 HP/PA Pro target hppa*-*-pro*
4673 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4674 386BSD i[3456]86-*-bsd*
4675 Sequent family i[3456]86-sequent-sysv4*
4676 i[3456]86-sequent-sysv*
4677 i[3456]86-sequent-bsd*
4678 SPARC running LynxOS sparc-*-lynxos*
4679 SPARC running SunOS 4 sparc-*-sunos4*
4680 Tsqware Sparclet sparclet-*-*
4681 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4683 *** Changes in GDB 6.0:
4687 Support for debugging the Objective-C programming language has been
4688 integrated into GDB.
4690 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4692 DWARF 2's Call Frame Information makes available compiler generated
4693 information that more exactly describes the program's run-time stack.
4694 By using this information, GDB is able to provide more robust stack
4697 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4698 have been updated to use a new backtrace mechanism which includes
4699 DWARF 2 CFI support.
4703 GDB's remote protocol has been extended to include support for hosted
4704 file I/O (where the remote target uses GDB's file system). See GDB's
4705 remote protocol documentation for details.
4707 * All targets using the new architecture framework.
4709 All of GDB's targets have been updated to use the new internal
4710 architecture framework. The way is now open for future GDB releases
4711 to include cross-architecture native debugging support (i386 on amd64,
4714 * GNU/Linux's Thread Local Storage (TLS)
4716 GDB now includes support for for the GNU/Linux implementation of
4717 per-thread variables.
4719 * GNU/Linux's Native POSIX Thread Library (NPTL)
4721 GDB's thread code has been updated to work with either the new
4722 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4724 * Separate debug info.
4726 GDB, in conjunction with BINUTILS, now supports a mechanism for
4727 automatically loading debug information from a separate file. Instead
4728 of shipping full debug and non-debug versions of system libraries,
4729 system integrators can now instead ship just the stripped libraries
4730 and optional debug files.
4732 * DWARF 2 Location Expressions
4734 DWARF 2 Location Expressions allow the compiler to more completely
4735 describe the location of variables (even in optimized code) to the
4738 GDB now includes preliminary support for location expressions (support
4739 for DW_OP_piece is still missing).
4743 A number of long standing bugs that caused GDB to die while starting a
4744 Java application have been fixed. GDB's Java support is now
4745 considered "useable".
4747 * GNU/Linux support for fork, vfork, and exec.
4749 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4750 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4753 * GDB supports logging output to a file
4755 There are two new commands, "set logging" and "show logging", which can be
4756 used to capture GDB's output to a file.
4758 * The meaning of "detach" has changed for gdbserver
4760 The "detach" command will now resume the application, as documented. To
4761 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4764 * d10v, m68hc11 `regs' command deprecated
4766 The `info registers' command has been updated so that it displays the
4767 registers using a format identical to the old `regs' command.
4771 A new command, "maint set profile on/off", has been added. This command can
4772 be used to enable or disable profiling while running GDB, to profile a
4773 session or a set of commands. In addition there is a new configure switch,
4774 "--enable-profiling", which will cause GDB to be compiled with profiling
4775 data, for more informative profiling results.
4777 * Default MI syntax changed to "mi2".
4779 The default MI (machine interface) syntax, enabled by the command line
4780 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4781 "mi1", can be enabled by specifying the option "-i=mi1".
4783 Support for the original "mi0" syntax (included in GDB 5.0) has been
4786 Fix for gdb/192: removed extraneous space when displaying frame level.
4787 Fix for gdb/672: update changelist is now output in mi list format.
4788 Fix for gdb/702: a -var-assign that updates the value now shows up
4789 in a subsequent -var-update.
4791 * New native configurations.
4793 FreeBSD/amd64 x86_64-*-freebsd*
4795 * Multi-arched targets.
4797 HP/PA HPUX11 hppa*-*-hpux*
4798 Renesas M32R/D w/simulator m32r-*-elf*
4800 * OBSOLETE configurations and files
4802 Configurations that have been declared obsolete in this release have
4803 been commented out. Unless there is activity to revive these
4804 configurations, the next release of GDB will have their sources
4805 permanently REMOVED.
4807 Z8000 simulator z8k-zilog-none or z8ksim
4808 Matsushita MN10200 w/simulator mn10200-*-*
4809 H8/500 simulator h8500-hitachi-hms or h8500hms
4810 HP/PA running BSD hppa*-*-bsd*
4811 HP/PA running OSF/1 hppa*-*-osf*
4812 HP/PA Pro target hppa*-*-pro*
4813 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4814 Sequent family i[3456]86-sequent-sysv4*
4815 i[3456]86-sequent-sysv*
4816 i[3456]86-sequent-bsd*
4817 Tsqware Sparclet sparclet-*-*
4818 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4820 * REMOVED configurations and files
4823 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4824 IBM AIX PS/2 i[3456]86-*-aix
4825 i386 running Mach 3.0 i[3456]86-*-mach3*
4826 i386 running Mach i[3456]86-*-mach*
4827 i386 running OSF/1 i[3456]86-*osf1mk*
4828 HP/Apollo 68k Family m68*-apollo*-sysv*,
4830 m68*-hp-bsd*, m68*-hp-hpux*
4831 Argonaut Risc Chip (ARC) arc-*-*
4832 Mitsubishi D30V d30v-*-*
4833 Fujitsu FR30 fr30-*-elf*
4834 OS/9000 i[34]86-*-os9k
4835 I960 with MON960 i960-*-coff
4837 * MIPS $fp behavior changed
4839 The convenience variable $fp, for the MIPS, now consistently returns
4840 the address of the current frame's base. Previously, depending on the
4841 context, $fp could refer to either $sp or the current frame's base
4842 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4843 The GNU Source-Level Debugger''.
4845 *** Changes in GDB 5.3:
4847 * GNU/Linux shared library multi-threaded performance improved.
4849 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4850 `/proc', in preference to `ptrace' for memory reads. This may result
4851 in an improvement in the start-up time of multi-threaded, shared
4852 library applications when run under GDB. One GDB user writes: ``loads
4853 shared libs like mad''.
4855 * ``gdbserver'' now supports multi-threaded applications on some targets
4857 Support for debugging multi-threaded applications which use
4858 the GNU/Linux LinuxThreads package has been added for
4859 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4860 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4862 * GDB now supports C/C++ preprocessor macros.
4864 GDB now expands preprocessor macro invocations in C/C++ expressions,
4865 and provides various commands for showing macro definitions and how
4868 The new command `macro expand EXPRESSION' expands any macro
4869 invocations in expression, and shows the result.
4871 The new command `show macro MACRO-NAME' shows the definition of the
4872 macro named MACRO-NAME, and where it was defined.
4874 Most compilers don't include information about macros in the debugging
4875 information by default. In GCC 3.1, for example, you need to compile
4876 your program with the options `-gdwarf-2 -g3'. If the macro
4877 information is present in the executable, GDB will read it.
4879 * Multi-arched targets.
4881 DEC Alpha (partial) alpha*-*-*
4882 DEC VAX (partial) vax-*-*
4884 National Semiconductor NS32000 (partial) ns32k-*-*
4885 Motorola 68000 (partial) m68k-*-*
4886 Motorola MCORE mcore-*-*
4890 Fujitsu FRV architecture added by Red Hat frv*-*-*
4893 * New native configurations
4895 Alpha NetBSD alpha*-*-netbsd*
4896 SH NetBSD sh*-*-netbsdelf*
4897 MIPS NetBSD mips*-*-netbsd*
4898 UltraSPARC NetBSD sparc64-*-netbsd*
4900 * OBSOLETE configurations and files
4902 Configurations that have been declared obsolete in this release have
4903 been commented out. Unless there is activity to revive these
4904 configurations, the next release of GDB will have their sources
4905 permanently REMOVED.
4907 Mitsubishi D30V d30v-*-*
4908 OS/9000 i[34]86-*-os9k
4909 IBM AIX PS/2 i[3456]86-*-aix
4910 Fujitsu FR30 fr30-*-elf*
4911 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4912 Argonaut Risc Chip (ARC) arc-*-*
4913 i386 running Mach 3.0 i[3456]86-*-mach3*
4914 i386 running Mach i[3456]86-*-mach*
4915 i386 running OSF/1 i[3456]86-*osf1mk*
4916 HP/Apollo 68k Family m68*-apollo*-sysv*,
4918 m68*-hp-bsd*, m68*-hp-hpux*
4919 I960 with MON960 i960-*-coff
4921 * OBSOLETE languages
4923 CHILL, a Pascal like language used by telecommunications companies.
4925 * REMOVED configurations and files
4927 AMD 29k family via UDI a29k-amd-udi, udi29k
4928 A29K VxWorks a29k-*-vxworks
4929 AMD 29000 embedded, using EBMON a29k-none-none
4930 AMD 29000 embedded with COFF a29k-none-coff
4931 AMD 29000 embedded with a.out a29k-none-aout
4933 testsuite/gdb.hp/gdb.threads-hp/ directory
4935 * New command "set max-user-call-depth <nnn>"
4937 This command allows the user to limit the call depth of user-defined
4938 commands. The default is 1024.
4940 * Changes in FreeBSD/i386 native debugging.
4942 Support for the "generate-core-file" has been added.
4944 * New commands "dump", "append", and "restore".
4946 These commands allow data to be copied from target memory
4947 to a bfd-format or binary file (dump and append), and back
4948 from a file into memory (restore).
4950 * Improved "next/step" support on multi-processor Alpha Tru64.
4952 The previous single-step mechanism could cause unpredictable problems,
4953 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4954 of a software single-step mechanism prevents this.
4956 *** Changes in GDB 5.2.1:
4964 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4965 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4966 Fix, by Joel Brobecker imported from mainline.
4968 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4969 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4970 Fix, by Fred Fish, imported from mainline.
4972 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4973 Surprisingly enough, it works now.
4974 By Michal Ludvig, imported from mainline.
4976 i386 hardware watchpoint support:
4977 avoid misses on second run for some targets.
4978 By Pierre Muller, imported from mainline.
4980 *** Changes in GDB 5.2:
4982 * New command "set trust-readonly-sections on[off]".
4984 This command is a hint that tells gdb that read-only sections
4985 really are read-only (ie. that their contents will not change).
4986 In this mode, gdb will go to the object file rather than the
4987 target to read memory from read-only sections (such as ".text").
4988 This can be a significant performance improvement on some
4989 (notably embedded) targets.
4991 * New command "generate-core-file" (or "gcore").
4993 This new gdb command allows the user to drop a core file of the child
4994 process state at any time. So far it's been implemented only for
4995 GNU/Linux and Solaris, but should be relatively easily ported to other
4996 hosts. Argument is core file name (defaults to core.<pid>).
4998 * New command line option
5000 GDB now accepts --pid or -p followed by a process id.
5002 * Change in command line behavior -- corefiles vs. process ids.
5004 There is a subtle behavior in the way in which GDB handles
5005 command line arguments. The first non-flag argument is always
5006 a program to debug, but the second non-flag argument may either
5007 be a corefile or a process id. Previously, GDB would attempt to
5008 open the second argument as a corefile, and if that failed, would
5009 issue a superfluous error message and then attempt to attach it as
5010 a process. Now, if the second argument begins with a non-digit,
5011 it will be treated as a corefile. If it begins with a digit,
5012 GDB will attempt to attach it as a process, and if no such process
5013 is found, will then attempt to open it as a corefile.
5015 * Changes in ARM configurations.
5017 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
5018 configuration is fully multi-arch.
5020 * New native configurations
5022 ARM NetBSD arm*-*-netbsd*
5023 x86 OpenBSD i[3456]86-*-openbsd*
5024 AMD x86-64 running GNU/Linux x86_64-*-linux-*
5025 Sparc64 running FreeBSD sparc64-*-freebsd*
5029 Sanyo XStormy16 xstormy16-elf
5031 * OBSOLETE configurations and files
5033 Configurations that have been declared obsolete in this release have
5034 been commented out. Unless there is activity to revive these
5035 configurations, the next release of GDB will have their sources
5036 permanently REMOVED.
5038 AMD 29k family via UDI a29k-amd-udi, udi29k
5039 A29K VxWorks a29k-*-vxworks
5040 AMD 29000 embedded, using EBMON a29k-none-none
5041 AMD 29000 embedded with COFF a29k-none-coff
5042 AMD 29000 embedded with a.out a29k-none-aout
5044 testsuite/gdb.hp/gdb.threads-hp/ directory
5046 * REMOVED configurations and files
5048 TI TMS320C80 tic80-*-*
5050 PowerPC Solaris powerpcle-*-solaris*
5051 PowerPC Windows NT powerpcle-*-cygwin32
5052 PowerPC Netware powerpc-*-netware*
5053 Harris/CXUX m88k m88*-harris-cxux*
5054 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5055 ns32k-utek-sysv* ns32k-utek-*
5056 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5057 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5058 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5059 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5060 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
5062 * Changes to command line processing
5064 The new `--args' feature can be used to specify command-line arguments
5065 for the inferior from gdb's command line.
5067 * Changes to key bindings
5069 There is a new `operate-and-get-next' function bound to `C-o'.
5071 *** Changes in GDB 5.1.1
5073 Fix compile problem on DJGPP.
5075 Fix a problem with floating-point registers on the i386 being
5078 Fix to stop GDB crashing on .debug_str debug info.
5080 Numerous documentation fixes.
5082 Numerous testsuite fixes.
5084 *** Changes in GDB 5.1:
5086 * New native configurations
5088 Alpha FreeBSD alpha*-*-freebsd*
5089 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
5090 MIPS GNU/Linux mips*-*-linux*
5091 MIPS SGI Irix 6.x mips*-sgi-irix6*
5092 ia64 AIX ia64-*-aix*
5093 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
5097 Motorola 68HC11 and 68HC12 m68hc11-elf
5099 UltraSparc running GNU/Linux sparc64-*-linux*
5101 * OBSOLETE configurations and files
5103 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
5104 Harris/CXUX m88k m88*-harris-cxux*
5105 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5106 ns32k-utek-sysv* ns32k-utek-*
5107 TI TMS320C80 tic80-*-*
5109 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5110 PowerPC Solaris powerpcle-*-solaris*
5111 PowerPC Windows NT powerpcle-*-cygwin32
5112 PowerPC Netware powerpc-*-netware*
5113 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5114 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5115 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5116 Apple Macintosh (MPW) host N/A
5118 stuff.c (Program to stuff files into a specially prepared space in kdb)
5119 kdb-start.c (Main loop for the standalone kernel debugger)
5121 Configurations that have been declared obsolete in this release have
5122 been commented out. Unless there is activity to revive these
5123 configurations, the next release of GDB will have their sources
5124 permanently REMOVED.
5126 * REMOVED configurations and files
5128 Altos 3068 m68*-altos-*
5129 Convex c1-*-*, c2-*-*
5131 ARM RISCix arm-*-* (as host)
5135 * GDB has been converted to ISO C.
5137 GDB's source code has been converted to ISO C. In particular, the
5138 sources are fully protoized, and rely on standard headers being
5143 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
5145 * The MI enabled by default.
5147 The new machine oriented interface (MI) introduced in GDB 5.0 has been
5148 revised and enabled by default. Packages which use GDB as a debugging
5149 engine behind a UI or another front end are encouraged to switch to
5150 using the GDB/MI interface, instead of the old annotations interface
5151 which is now deprecated.
5153 * Support for debugging Pascal programs.
5155 GDB now includes support for debugging Pascal programs. The following
5156 main features are supported:
5158 - Pascal-specific data types such as sets;
5160 - automatic recognition of Pascal sources based on file-name
5163 - Pascal-style display of data types, variables, and functions;
5165 - a Pascal expression parser.
5167 However, some important features are not yet supported.
5169 - Pascal string operations are not supported at all;
5171 - there are some problems with boolean types;
5173 - Pascal type hexadecimal constants are not supported
5174 because they conflict with the internal variables format;
5176 - support for Pascal objects and classes is not full yet;
5178 - unlike Pascal, GDB is case-sensitive for symbol names.
5180 * Changes in completion.
5182 Commands such as `shell', `run' and `set args', which pass arguments
5183 to inferior programs, now complete on file names, similar to what
5184 users expect at the shell prompt.
5186 Commands which accept locations, such as `disassemble', `print',
5187 `breakpoint', `until', etc. now complete on filenames as well as
5188 program symbols. Thus, if you type "break foob TAB", and the source
5189 files linked into the programs include `foobar.c', that file name will
5190 be one of the candidates for completion. However, file names are not
5191 considered for completion after you typed a colon that delimits a file
5192 name from a name of a function in that file, as in "break foo.c:bar".
5194 `set demangle-style' completes on available demangling styles.
5196 * New platform-independent commands:
5198 It is now possible to define a post-hook for a command as well as a
5199 hook that runs before the command. For more details, see the
5200 documentation of `hookpost' in the GDB manual.
5202 * Changes in GNU/Linux native debugging.
5204 Support for debugging multi-threaded programs has been completely
5205 revised for all platforms except m68k and sparc. You can now debug as
5206 many threads as your system allows you to have.
5208 Attach/detach is supported for multi-threaded programs.
5210 Support for SSE registers was added for x86. This doesn't work for
5211 multi-threaded programs though.
5213 * Changes in MIPS configurations.
5215 Multi-arch support is enabled for all MIPS configurations.
5217 GDB can now be built as native debugger on SGI Irix 6.x systems for
5218 debugging n32 executables. (Debugging 64-bit executables is not yet
5221 * Unified support for hardware watchpoints in all x86 configurations.
5223 Most (if not all) native x86 configurations support hardware-assisted
5224 breakpoints and watchpoints in a unified manner. This support
5225 implements debug register sharing between watchpoints, which allows to
5226 put a virtually infinite number of watchpoints on the same address,
5227 and also supports watching regions up to 16 bytes with several debug
5230 The new maintenance command `maintenance show-debug-regs' toggles
5231 debugging print-outs in functions that insert, remove, and test
5232 watchpoints and hardware breakpoints.
5234 * Changes in the DJGPP native configuration.
5236 New command ``info dos sysinfo'' displays assorted information about
5237 the CPU, OS, memory, and DPMI server.
5239 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
5240 display information about segment descriptors stored in GDT, LDT, and
5243 New commands ``info dos pde'' and ``info dos pte'' display entries
5244 from Page Directory and Page Tables (for now works with CWSDPMI only).
5245 New command ``info dos address-pte'' displays the Page Table entry for
5246 a given linear address.
5248 GDB can now pass command lines longer than 126 characters to the
5249 program being debugged (requires an update to the libdbg.a library
5250 which is part of the DJGPP development kit).
5252 DWARF2 debug info is now supported.
5254 It is now possible to `step' and `next' through calls to `longjmp'.
5256 * Changes in documentation.
5258 All GDB documentation was converted to GFDL, the GNU Free
5259 Documentation License.
5261 Tracepoints-related commands are now fully documented in the GDB
5264 TUI, the Text-mode User Interface, is now documented in the manual.
5266 Tracepoints-related commands are now fully documented in the GDB
5269 The "GDB Internals" manual now has an index. It also includes
5270 documentation of `ui_out' functions, GDB coding standards, x86
5271 hardware watchpoints, and memory region attributes.
5273 * GDB's version number moved to ``version.in''
5275 The Makefile variable VERSION has been replaced by the file
5276 ``version.in''. People creating GDB distributions should update the
5277 contents of this file.
5281 GUD support is now a standard part of the EMACS distribution.
5283 *** Changes in GDB 5.0:
5285 * Improved support for debugging FP programs on x86 targets
5287 Unified and much-improved support for debugging floating-point
5288 programs on all x86 targets. In particular, ``info float'' now
5289 displays the FP registers in the same format on all x86 targets, with
5290 greater level of detail.
5292 * Improvements and bugfixes in hardware-assisted watchpoints
5294 It is now possible to watch array elements, struct members, and
5295 bitfields with hardware-assisted watchpoints. Data-read watchpoints
5296 on x86 targets no longer erroneously trigger when the address is
5299 * Improvements in the native DJGPP version of GDB
5301 The distribution now includes all the scripts and auxiliary files
5302 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5303 machines ``out of the box''.
5305 The DJGPP version can now debug programs that use signals. It is
5306 possible to catch signals that happened in the debuggee, deliver
5307 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5308 would kill the program being debugged.) Programs that hook hardware
5309 interrupts (keyboard, timer, etc.) can also be debugged.
5311 It is now possible to debug DJGPP programs that redirect their
5312 standard handles or switch them to raw (as opposed to cooked) mode, or
5313 even close them. The command ``run < foo > bar'' works as expected,
5314 and ``info terminal'' reports useful information about the debuggee's
5315 terminal, including raw/cooked mode, redirection, etc.
5317 The DJGPP version now uses termios functions for console I/O, which
5318 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5321 DOS-style file names with drive letters are now fully supported by
5324 It is now possible to debug DJGPP programs that switch their working
5325 directory. It is also possible to rerun the debuggee any number of
5326 times without restarting GDB; thus, you can use the same setup,
5327 breakpoints, etc. for many debugging sessions.
5329 * New native configurations
5331 ARM GNU/Linux arm*-*-linux*
5332 PowerPC GNU/Linux powerpc-*-linux*
5336 Motorola MCore mcore-*-*
5337 x86 VxWorks i[3456]86-*-vxworks*
5338 PowerPC VxWorks powerpc-*-vxworks*
5339 TI TMS320C80 tic80-*-*
5341 * OBSOLETE configurations
5343 Altos 3068 m68*-altos-*
5344 Convex c1-*-*, c2-*-*
5346 ARM RISCix arm-*-* (as host)
5349 Configurations that have been declared obsolete will be commented out,
5350 but the code will be left in place. If there is no activity to revive
5351 these configurations before the next release of GDB, the sources will
5352 be permanently REMOVED.
5354 * Gould support removed
5356 Support for the Gould PowerNode and NP1 has been removed.
5358 * New features for SVR4
5360 On SVR4 native platforms (such as Solaris), if you attach to a process
5361 without first loading a symbol file, GDB will now attempt to locate and
5362 load symbols from the running process's executable file.
5364 * Many C++ enhancements
5366 C++ support has been greatly improved. Overload resolution now works properly
5367 in almost all cases. RTTI support is on the way.
5369 * Remote targets can connect to a sub-program
5371 A popen(3) style serial-device has been added. This device starts a
5372 sub-process (such as a stand-alone simulator) and then communicates
5373 with that. The sub-program to run is specified using the syntax
5374 ``|<program> <args>'' vis:
5376 (gdb) set remotedebug 1
5377 (gdb) target extended-remote |mn10300-elf-sim program-args
5379 * MIPS 64 remote protocol
5381 A long standing bug in the mips64 remote protocol where by GDB
5382 expected certain 32 bit registers (ex SR) to be transfered as 32
5383 instead of 64 bits has been fixed.
5385 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5386 added to provide backward compatibility with older versions of GDB.
5388 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5390 The command ``set remotebinarydownload'' command has been replaced by
5391 ``set remote X-packet''. Other commands in ``set remote'' family
5392 include ``set remote P-packet''.
5394 * Breakpoint commands accept ranges.
5396 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5397 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5398 ``tracepoint passcount'' also accepts a range of tracepoints.
5400 * ``apropos'' command added.
5402 The ``apropos'' command searches through command names and
5403 documentation strings, printing out matches, making it much easier to
5404 try to find a command that does what you are looking for.
5408 A new machine oriented interface (MI) has been added to GDB. This
5409 interface is designed for debug environments running GDB as a separate
5410 process. This is part of the long term libGDB project. See the
5411 "GDB/MI" chapter of the GDB manual for further information. It can be
5412 enabled by configuring with:
5414 .../configure --enable-gdbmi
5416 *** Changes in GDB-4.18:
5418 * New native configurations
5420 HP-UX 10.20 hppa*-*-hpux10.20
5421 HP-UX 11.x hppa*-*-hpux11.0*
5422 M68K GNU/Linux m68*-*-linux*
5426 Fujitsu FR30 fr30-*-elf*
5427 Intel StrongARM strongarm-*-*
5428 Mitsubishi D30V d30v-*-*
5430 * OBSOLETE configurations
5432 Gould PowerNode, NP1 np1-*-*, pn-*-*
5434 Configurations that have been declared obsolete will be commented out,
5435 but the code will be left in place. If there is no activity to revive
5436 these configurations before the next release of GDB, the sources will
5437 be permanently REMOVED.
5441 As a compatibility experiment, GDB's source files buildsym.h and
5442 buildsym.c have been converted to pure standard C, no longer
5443 containing any K&R compatibility code. We believe that all systems in
5444 use today either come with a standard C compiler, or have a GCC port
5445 available. If this is not true, please report the affected
5446 configuration to bug-gdb@gnu.org immediately. See the README file for
5447 information about getting a standard C compiler if you don't have one
5452 GDB now uses readline 2.2.
5454 * set extension-language
5456 You can now control the mapping between filename extensions and source
5457 languages by using the `set extension-language' command. For instance,
5458 you can ask GDB to treat .c files as C++ by saying
5459 set extension-language .c c++
5460 The command `info extensions' lists all of the recognized extensions
5461 and their associated languages.
5463 * Setting processor type for PowerPC and RS/6000
5465 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5466 you can use the `set processor' command to specify what variant of the
5467 PowerPC family you are debugging. The command
5471 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5472 following PowerPC and RS6000 variants:
5474 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5475 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5477 403GC IBM PowerPC 403GC
5478 505 Motorola PowerPC 505
5479 860 Motorola PowerPC 860 or 850
5480 601 Motorola PowerPC 601
5481 602 Motorola PowerPC 602
5482 603 Motorola/IBM PowerPC 603 or 603e
5483 604 Motorola PowerPC 604 or 604e
5484 750 Motorola/IBM PowerPC 750 or 750
5486 At the moment, this command just tells GDB what to name the
5487 special-purpose processor registers. Since almost all the affected
5488 registers are inaccessible to user-level programs, this command is
5489 only useful for remote debugging in its present form.
5493 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5494 more extensive support for HP-UX. Added features include shared
5495 library support, kernel threads and hardware watchpoints for 11.00,
5496 support for HP's ANSI C and C++ compilers, and a compatibility mode
5497 for xdb and dbx commands.
5501 HP's donation includes the new concept of catchpoints, which is a
5502 generalization of the old catch command. On HP-UX, it is now possible
5503 to catch exec, fork, and vfork, as well as library loading.
5505 This means that the existing catch command has changed; its first
5506 argument now specifies the type of catch to be set up. See the
5507 output of "help catch" for a list of catchpoint types.
5509 * Debugging across forks
5511 On HP-UX, you can choose which process to debug when a fork() happens
5516 HP has donated a curses-based terminal user interface (TUI). To get
5517 it, build with --enable-tui. Although this can be enabled for any
5518 configuration, at present it only works for native HP debugging.
5520 * GDB remote protocol additions
5522 A new protocol packet 'X' that writes binary data is now available.
5523 Default behavior is to try 'X', then drop back to 'M' if the stub
5524 fails to respond. The settable variable `remotebinarydownload'
5525 allows explicit control over the use of 'X'.
5527 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5528 full 64-bit address. The command
5530 set remoteaddresssize 32
5532 can be used to revert to the old behaviour. For existing remote stubs
5533 the change should not be noticed, as the additional address information
5536 In order to assist in debugging stubs, you may use the maintenance
5537 command `packet' to send any text string to the stub. For instance,
5539 maint packet heythere
5541 sends the packet "$heythere#<checksum>". Note that it is very easy to
5542 disrupt a debugging session by sending the wrong packet at the wrong
5545 The compare-sections command allows you to compare section data on the
5546 target to what is in the executable file without uploading or
5547 downloading, by comparing CRC checksums.
5549 * Tracing can collect general expressions
5551 You may now collect general expressions at tracepoints. This requires
5552 further additions to the target-side stub; see tracepoint.c and
5553 doc/agentexpr.texi for further details.
5555 * mask-address variable for Mips
5557 For Mips targets, you may control the zeroing of the upper 32 bits of
5558 a 64-bit address by entering `set mask-address on'. This is mainly
5559 of interest to users of embedded R4xxx and R5xxx processors.
5561 * Higher serial baud rates
5563 GDB's serial code now allows you to specify baud rates 57600, 115200,
5564 230400, and 460800 baud. (Note that your host system may not be able
5565 to achieve all of these rates.)
5569 The i960 configuration now includes an initial implementation of a
5570 builtin simulator, contributed by Jim Wilson.
5573 *** Changes in GDB-4.17:
5575 * New native configurations
5577 Alpha GNU/Linux alpha*-*-linux*
5578 Unixware 2.x i[3456]86-unixware2*
5579 Irix 6.x mips*-sgi-irix6*
5580 PowerPC GNU/Linux powerpc-*-linux*
5581 PowerPC Solaris powerpcle-*-solaris*
5582 Sparc GNU/Linux sparc-*-linux*
5583 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5587 Argonaut Risc Chip (ARC) arc-*-*
5588 Hitachi H8/300S h8300*-*-*
5589 Matsushita MN10200 w/simulator mn10200-*-*
5590 Matsushita MN10300 w/simulator mn10300-*-*
5591 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5592 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5593 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5594 Mitsubishi D10V w/simulator d10v-*-*
5595 Mitsubishi M32R/D w/simulator m32r-*-elf*
5596 Tsqware Sparclet sparclet-*-*
5597 NEC V850 w/simulator v850-*-*
5599 * New debugging protocols
5601 ARM with RDI protocol arm*-*-*
5602 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5603 DDB and LSI variants of PMON protocol mips*-*-*
5604 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5605 PowerPC with SDS protocol powerpc{,le}-*-eabi
5606 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5610 All configurations can now understand and use the DWARF 2 debugging
5611 format. The choice is automatic, if the symbol file contains DWARF 2
5616 GDB now includes basic Java language support. This support is
5617 only useful with Java compilers that produce native machine code.
5619 * solib-absolute-prefix and solib-search-path
5621 For SunOS and SVR4 shared libraries, you may now set the prefix for
5622 loading absolute shared library symbol files, and the search path for
5623 locating non-absolute shared library symbol files.
5625 * Live range splitting
5627 GDB can now effectively debug code for which GCC has performed live
5628 range splitting as part of its optimization. See gdb/doc/LRS for
5629 more details on the expected format of the stabs information.
5633 GDB's support for the GNU Hurd, including thread debugging, has been
5634 updated to work with current versions of the Hurd.
5638 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5639 instruction set. ARM GDB automatically detects when Thumb
5640 instructions are in use, and adjusts disassembly and backtracing
5645 GDB's MIPS target configurations now handle the MIP16 16-bit
5650 GDB now includes support for overlays; if an executable has been
5651 linked such that multiple sections are based at the same address, GDB
5652 will decide which section to use for symbolic info. You can choose to
5653 control the decision manually, using overlay commands, or implement
5654 additional target-side support and use "overlay load-target" to bring
5655 in the overlay mapping. Do "help overlay" for more detail.
5659 The command "info symbol <address>" displays information about
5660 the symbol at the specified address.
5664 The standard remote protocol now includes an extension that allows
5665 asynchronous collection and display of trace data. This requires
5666 extensive support in the target-side debugging stub. Tracing mode
5667 includes a new interaction mode in GDB and new commands: see the
5668 file tracepoint.c for more details.
5672 Configurations for embedded MIPS now include a simulator contributed
5673 by Cygnus Solutions. The simulator supports the instruction sets
5674 of most MIPS variants.
5678 Sparc configurations may now include the ERC32 simulator contributed
5679 by the European Space Agency. The simulator is not built into
5680 Sparc targets by default; configure with --enable-sim to include it.
5684 For target configurations that may include multiple variants of a
5685 basic architecture (such as MIPS and SH), you may now set the
5686 architecture explicitly. "set arch" sets, "info arch" lists
5687 the possible architectures.
5689 *** Changes in GDB-4.16:
5691 * New native configurations
5693 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5694 M68K NetBSD m68k-*-netbsd*
5695 PowerPC AIX 4.x powerpc-*-aix*
5696 PowerPC MacOS powerpc-*-macos*
5697 PowerPC Windows NT powerpcle-*-cygwin32
5698 RS/6000 AIX 4.x rs6000-*-aix4*
5702 ARM with RDP protocol arm-*-*
5703 I960 with MON960 i960-*-coff
5704 MIPS VxWorks mips*-*-vxworks*
5705 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5706 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5708 Matra Sparclet sparclet-*-*
5712 The powerpc-eabi configuration now includes the PSIM simulator,
5713 contributed by Andrew Cagney, with assistance from Mike Meissner.
5714 PSIM is a very elaborate model of the PowerPC, including not only
5715 basic instruction set execution, but also details of execution unit
5716 performance and I/O hardware. See sim/ppc/README for more details.
5720 GDB now works with Solaris 2.5.
5722 * Windows 95/NT native
5724 GDB will now work as a native debugger on Windows 95 and Windows NT.
5725 To build it from source, you must use the "gnu-win32" environment,
5726 which uses a DLL to emulate enough of Unix to run the GNU tools.
5727 Further information, binaries, and sources are available at
5728 ftp.cygnus.com, under pub/gnu-win32.
5730 * dont-repeat command
5732 If a user-defined command includes the command `dont-repeat', then the
5733 command will not be repeated if the user just types return. This is
5734 useful if the command is time-consuming to run, so that accidental
5735 extra keystrokes don't run the same command many times.
5737 * Send break instead of ^C
5739 The standard remote protocol now includes an option to send a break
5740 rather than a ^C to the target in order to interrupt it. By default,
5741 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5743 * Remote protocol timeout
5745 The standard remote protocol includes a new variable `remotetimeout'
5746 that allows you to set the number of seconds before GDB gives up trying
5747 to read from the target. The default value is 2.
5749 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5751 By default GDB will automatically keep track of objects as they are
5752 loaded and unloaded by the dynamic linker. By using the command `set
5753 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5754 when shared library events occur, thus allowing you to set breakpoints
5755 in shared libraries which are explicitly loaded by the inferior.
5757 Note this feature does not work on hpux8. On hpux9 you must link
5758 /usr/lib/end.o into your program. This feature should work
5759 automatically on hpux10.
5761 * Irix 5.x hardware watchpoint support
5763 Irix 5 configurations now support the use of hardware watchpoints.
5765 * Mips protocol "SYN garbage limit"
5767 When debugging a Mips target using the `target mips' protocol, you
5768 may set the number of characters that GDB will ignore by setting
5769 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5770 every character. The default value is 1050.
5772 * Recording and replaying remote debug sessions
5774 If you set `remotelogfile' to the name of a file, gdb will write to it
5775 a recording of a remote debug session. This recording may then be
5776 replayed back to gdb using "gdbreplay". See gdbserver/README for
5777 details. This is useful when you have a problem with GDB while doing
5778 remote debugging; you can make a recording of the session and send it
5779 to someone else, who can then recreate the problem.
5781 * Speedups for remote debugging
5783 GDB includes speedups for downloading and stepping MIPS systems using
5784 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5785 and more efficient S-record downloading.
5787 * Memory use reductions and statistics collection
5789 GDB now uses less memory and reports statistics about memory usage.
5790 Try the `maint print statistics' command, for example.
5792 *** Changes in GDB-4.15:
5794 * Psymtabs for XCOFF
5796 The symbol reader for AIX GDB now uses partial symbol tables. This
5797 can greatly improve startup time, especially for large executables.
5799 * Remote targets use caching
5801 Remote targets now use a data cache to speed up communication with the
5802 remote side. The data cache could lead to incorrect results because
5803 it doesn't know about volatile variables, thus making it impossible to
5804 debug targets which use memory mapped I/O devices. `set remotecache
5805 off' turns the the data cache off.
5807 * Remote targets may have threads
5809 The standard remote protocol now includes support for multiple threads
5810 in the target system, using new protocol commands 'H' and 'T'. See
5811 gdb/remote.c for details.
5815 If GDB is configured with `--enable-netrom', then it will include
5816 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5817 acts as though it is a bank of ROM on the target board, but you can
5818 write into it over the network. GDB's support consists only of
5819 support for fast loading into the emulated ROM; to debug, you must use
5820 another protocol, such as standard remote protocol. The usual
5821 sequence is something like
5823 target nrom <netrom-hostname>
5825 target remote <netrom-hostname>:1235
5829 GDB now includes support for the Apple Macintosh, as a host only. It
5830 may be run as either an MPW tool or as a standalone application, and
5831 it can debug through the serial port. All the usual GDB commands are
5832 available, but to the target command, you must supply "serial" as the
5833 device type instead of "/dev/ttyXX". See mpw-README in the main
5834 directory for more information on how to build. The MPW configuration
5835 scripts */mpw-config.in support only a few targets, and only the
5836 mips-idt-ecoff target has been tested.
5840 GDB configuration now uses autoconf. This is not user-visible,
5841 but does simplify configuration and building.
5845 GDB now supports hpux10.
5847 *** Changes in GDB-4.14:
5849 * New native configurations
5851 x86 FreeBSD i[345]86-*-freebsd
5852 x86 NetBSD i[345]86-*-netbsd
5853 NS32k NetBSD ns32k-*-netbsd
5854 Sparc NetBSD sparc-*-netbsd
5858 A29K VxWorks a29k-*-vxworks
5859 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5860 CPU32 EST-300 emulator m68*-*-est*
5861 PowerPC ELF powerpc-*-elf
5864 * Alpha OSF/1 support for procfs
5866 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5867 possible to attach to running processes. As the mounting of the /proc
5868 filesystem is optional on the Alpha, GDB automatically determines
5869 the availability of /proc during startup. This can lead to problems
5870 if /proc is unmounted after GDB has been started.
5872 * Arguments to user-defined commands
5874 User commands may accept up to 10 arguments separated by whitespace.
5875 Arguments are accessed within the user command via $arg0..$arg9. A
5878 print $arg0 + $arg1 + $arg2
5880 To execute the command use:
5883 Defines the command "adder" which prints the sum of its three arguments.
5884 Note the arguments are text substitutions, so they may reference variables,
5885 use complex expressions, or even perform inferior function calls.
5887 * New `if' and `while' commands
5889 This makes it possible to write more sophisticated user-defined
5890 commands. Both commands take a single argument, which is the
5891 expression to evaluate, and must be followed by the commands to
5892 execute, one per line, if the expression is nonzero, the list being
5893 terminated by the word `end'. The `if' command list may include an
5894 `else' word, which causes the following commands to be executed only
5895 if the expression is zero.
5897 * Fortran source language mode
5899 GDB now includes partial support for Fortran 77. It will recognize
5900 Fortran programs and can evaluate a subset of Fortran expressions, but
5901 variables and functions may not be handled correctly. GDB will work
5902 with G77, but does not yet know much about symbols emitted by other
5905 * Better HPUX support
5907 Most debugging facilities now work on dynamic executables for HPPAs
5908 running hpux9 or later. You can attach to running dynamically linked
5909 processes, but by default the dynamic libraries will be read-only, so
5910 for instance you won't be able to put breakpoints in them. To change
5911 that behavior do the following before running the program:
5917 This will cause the libraries to be mapped private and read-write.
5918 To revert to the normal behavior, do this:
5924 You cannot set breakpoints or examine data in the library until after
5925 the library is loaded if the function/data symbols do not have
5928 GDB can now also read debug symbols produced by the HP C compiler on
5929 HPPAs (sorry, no C++, Fortran or 68k support).
5931 * Target byte order now dynamically selectable
5933 You can choose which byte order to use with a target system, via the
5934 commands "set endian big" and "set endian little", and you can see the
5935 current setting by using "show endian". You can also give the command
5936 "set endian auto", in which case GDB will use the byte order
5937 associated with the executable. Currently, only embedded MIPS
5938 configurations support dynamic selection of target byte order.
5940 * New DOS host serial code
5942 This version uses DPMI interrupts to handle buffered I/O, so you
5943 no longer need to run asynctsr when debugging boards connected to
5946 *** Changes in GDB-4.13:
5948 * New "complete" command
5950 This lists all the possible completions for the rest of the line, if it
5951 were to be given as a command itself. This is intended for use by emacs.
5953 * Trailing space optional in prompt
5955 "set prompt" no longer adds a space for you after the prompt you set. This
5956 allows you to set a prompt which ends in a space or one that does not.
5958 * Breakpoint hit counts
5960 "info break" now displays a count of the number of times the breakpoint
5961 has been hit. This is especially useful in conjunction with "ignore"; you
5962 can ignore a large number of breakpoint hits, look at the breakpoint info
5963 to see how many times the breakpoint was hit, then run again, ignoring one
5964 less than that number, and this will get you quickly to the last hit of
5967 * Ability to stop printing at NULL character
5969 "set print null-stop" will cause GDB to stop printing the characters of
5970 an array when the first NULL is encountered. This is useful when large
5971 arrays actually contain only short strings.
5973 * Shared library breakpoints
5975 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5976 breakpoints in shared libraries before the executable is run.
5978 * Hardware watchpoints
5980 There is a new hardware breakpoint for the watch command for sparclite
5981 targets. See gdb/sparclite/hw_breakpoint.note.
5983 Hardware watchpoints are also now supported under GNU/Linux.
5987 Annotations have been added. These are for use with graphical interfaces,
5988 and are still experimental. Currently only gdba.el uses these.
5990 * Improved Irix 5 support
5992 GDB now works properly with Irix 5.2.
5994 * Improved HPPA support
5996 GDB now works properly with the latest GCC and GAS.
5998 * New native configurations
6000 Sequent PTX4 i[34]86-sequent-ptx4
6001 HPPA running OSF/1 hppa*-*-osf*
6002 Atari TT running SVR4 m68*-*-sysv4*
6003 RS/6000 LynxOS rs6000-*-lynxos*
6007 OS/9000 i[34]86-*-os9k
6008 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
6011 * Hitachi SH7000 and E7000-PC ICE support
6013 There is now support for communicating with the Hitachi E7000-PC ICE.
6014 This is available automatically when GDB is configured for the SH.
6018 As usual, a variety of small fixes and improvements, both generic
6019 and configuration-specific. See the ChangeLog for more detail.
6021 *** Changes in GDB-4.12:
6023 * Irix 5 is now supported
6027 GDB-4.12 on the HPPA has a number of changes which make it unable
6028 to debug the output from the currently released versions of GCC and
6029 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
6030 of GCC and GAS, versions of these tools designed to work with GDB-4.12
6031 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
6034 *** Changes in GDB-4.11:
6036 * User visible changes:
6040 The "set remotedebug" option is now consistent between the mips remote
6041 target, remote targets using the gdb-specific protocol, UDI (AMD's
6042 debug protocol for the 29k) and the 88k bug monitor. It is now an
6043 integer specifying a debug level (normally 0 or 1, but 2 means more
6044 debugging info for the mips target).
6046 * DEC Alpha native support
6048 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
6049 debug info, but GDB works fairly well with the DEC compiler and should
6050 work with a future GCC release. See the README file for a few
6051 Alpha-specific notes.
6053 * Preliminary thread implementation
6055 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
6057 * LynxOS native and target support for 386
6059 This release has been hosted on LynxOS 2.2, and also can be configured
6060 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
6063 * Improvements in C++ mangling/demangling.
6065 This release has much better g++ debugging, specifically in name
6066 mangling/demangling, virtual function calls, print virtual table,
6067 call methods, ...etc.
6069 *** Changes in GDB-4.10:
6071 * User visible changes:
6073 Remote debugging using the GDB-specific (`target remote') protocol now
6074 supports the `load' command. This is only useful if you have some
6075 other way of getting the stub to the target system, and you can put it
6076 somewhere in memory where it won't get clobbered by the download.
6078 Filename completion now works.
6080 When run under emacs mode, the "info line" command now causes the
6081 arrow to point to the line specified. Also, "info line" prints
6082 addresses in symbolic form (as well as hex).
6084 All vxworks based targets now support a user settable option, called
6085 vxworks-timeout. This option represents the number of seconds gdb
6086 should wait for responses to rpc's. You might want to use this if
6087 your vxworks target is, perhaps, a slow software simulator or happens
6088 to be on the far side of a thin network line.
6092 This release contains support for using a DEC alpha as a GDB host for
6093 cross debugging. Native alpha debugging is not supported yet.
6096 *** Changes in GDB-4.9:
6100 This is the first GDB release which is accompanied by a matching testsuite.
6101 The testsuite requires installation of dejagnu, which should be available
6102 via ftp from most sites that carry GNU software.
6106 'Cfront' style demangling has had its name changed to 'ARM' style, to
6107 emphasize that it was written from the specifications in the C++ Annotated
6108 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
6109 disclaimers, it still generated too much confusion with users attempting to
6110 use gdb with AT&T cfront.
6114 GDB now uses a standard remote interface to a simulator library.
6115 So far, the library contains simulators for the Zilog Z8001/2, the
6116 Hitachi H8/300, H8/500 and Super-H.
6118 * New targets supported
6120 H8/300 simulator h8300-hitachi-hms or h8300hms
6121 H8/500 simulator h8500-hitachi-hms or h8500hms
6122 SH simulator sh-hitachi-hms or sh
6123 Z8000 simulator z8k-zilog-none or z8ksim
6124 IDT MIPS board over serial line mips-idt-ecoff
6126 Cross-debugging to GO32 targets is supported. It requires a custom
6127 version of the i386-stub.c module which is integrated with the
6128 GO32 memory extender.
6130 * New remote protocols
6132 MIPS remote debugging protocol.
6134 * New source languages supported
6136 This version includes preliminary support for Chill, a Pascal like language
6137 used by telecommunications companies. Chill support is also being integrated
6138 into the GNU compiler, but we don't know when it will be publically available.
6141 *** Changes in GDB-4.8:
6143 * HP Precision Architecture supported
6145 GDB now supports HP PA-RISC machines running HPUX. A preliminary
6146 version of this support was available as a set of patches from the
6147 University of Utah. GDB does not support debugging of programs
6148 compiled with the HP compiler, because HP will not document their file
6149 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
6150 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
6152 Many problems in the preliminary version have been fixed.
6154 * Faster and better demangling
6156 We have improved template demangling and fixed numerous bugs in the GNU style
6157 demangler. It can now handle type modifiers such as `static' or `const'. Wide
6158 character types (wchar_t) are now supported. Demangling of each symbol is now
6159 only done once, and is cached when the symbol table for a file is read in.
6160 This results in a small increase in memory usage for C programs, a moderate
6161 increase in memory usage for C++ programs, and a fantastic speedup in
6164 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
6165 from the specifications in the Annotated Reference Manual, which AT&T's
6166 compiler does not actually implement.
6168 * G++ multiple inheritance compiler problem
6170 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
6171 inheritance lattices was reworked to properly discover ambiguities. We
6172 recently found an example which causes this new algorithm to fail in a
6173 very subtle way, producing bad debug information for those classes.
6174 The file 'gcc.patch' (in this directory) can be applied to gcc to
6175 circumvent the problem. A future GCC release will contain a complete
6178 The previous G++ debug info problem (mentioned below for the gdb-4.7
6179 release) is fixed in gcc version 2.3.2.
6181 * Improved configure script
6183 The `configure' script will now attempt to guess your system type if
6184 you don't supply a host system type. The old scheme of supplying a
6185 host system triplet is preferable over using this. All the magic is
6186 done in the new `config.guess' script. Examine it for details.
6188 We have also brought our configure script much more in line with the FSF's
6189 version. It now supports the --with-xxx options. In particular,
6190 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
6191 The resulting GDB will not be able to read arbitrary object file formats --
6192 only the format ``expected'' to be used on the configured target system.
6193 We hope to make this the default in a future release.
6195 * Documentation improvements
6197 There's new internal documentation on how to modify GDB, and how to
6198 produce clean changes to the code. We implore people to read it
6199 before submitting changes.
6201 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
6202 M4 macros. The new texinfo.tex is provided in this release. Pre-built
6203 `info' files are also provided. To build `info' files from scratch,
6204 you will need the latest `makeinfo' release, which will be available in
6205 a future texinfo-X.Y release.
6207 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
6208 We're not sure exactly which versions have this problem, but it has
6209 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
6210 or better. If that isn't possible, there is a patch in
6211 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
6212 around this problem.
6216 GDB now supports array constants that can be used in expressions typed in by
6217 the user. The syntax is `{element, element, ...}'. Ie: you can now type
6218 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
6221 The new directory `gdb/sparclite' contains a program that demonstrates
6222 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
6224 * New native hosts supported
6226 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
6227 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
6229 * New targets supported
6231 AMD 29k family via UDI a29k-amd-udi or udi29k
6233 * New file formats supported
6235 BFD now supports reading HP/PA-RISC executables (SOM file format?),
6236 HPUX core files, and SCO 3.2v2 core files.
6240 Attaching to processes now works again; thanks for the many bug reports.
6242 We have also stomped on a bunch of core dumps caused by
6243 printf_filtered("%s") problems.
6245 We eliminated a copyright problem on the rpc and ptrace header files
6246 for VxWorks, which was discovered at the last minute during the 4.7
6247 release. You should now be able to build a VxWorks GDB.
6249 You can now interrupt gdb while an attached process is running. This
6250 will cause the attached process to stop, and give control back to GDB.
6252 We fixed problems caused by using too many file descriptors
6253 for reading symbols from object files and libraries. This was
6254 especially a problem for programs that used many (~100) shared
6257 The `step' command now only enters a subroutine if there is line number
6258 information for the subroutine. Otherwise it acts like the `next'
6259 command. Previously, `step' would enter subroutines if there was
6260 any debugging information about the routine. This avoids problems
6261 when using `cc -g1' on MIPS machines.
6263 * Internal improvements
6265 GDB's internal interfaces have been improved to make it easier to support
6266 debugging of multiple languages in the future.
6268 GDB now uses a common structure for symbol information internally.
6269 Minimal symbols (derived from linkage symbols in object files), partial
6270 symbols (from a quick scan of debug information), and full symbols
6271 contain a common subset of information, making it easier to write
6272 shared code that handles any of them.
6274 * New command line options
6276 We now accept --silent as an alias for --quiet.
6280 The memory-mapped-malloc library is now licensed under the GNU Library
6281 General Public License.
6283 *** Changes in GDB-4.7:
6285 * Host/native/target split
6287 GDB has had some major internal surgery to untangle the support for
6288 hosts and remote targets. Now, when you configure GDB for a remote
6289 target, it will no longer load in all of the support for debugging
6290 local programs on the host. When fully completed and tested, this will
6291 ensure that arbitrary host/target combinations are possible.
6293 The primary conceptual shift is to separate the non-portable code in
6294 GDB into three categories. Host specific code is required any time GDB
6295 is compiled on that host, regardless of the target. Target specific
6296 code relates to the peculiarities of the target, but can be compiled on
6297 any host. Native specific code is everything else: it can only be
6298 built when the host and target are the same system. Child process
6299 handling and core file support are two common `native' examples.
6301 GDB's use of /proc for controlling Unix child processes is now cleaner.
6302 It has been split out into a single module under the `target_ops' vector,
6303 plus two native-dependent functions for each system that uses /proc.
6305 * New hosts supported
6307 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6308 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6309 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6311 * New targets supported
6313 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6314 68030 and CPU32 m68030-*-*, m68332-*-*
6316 * New native hosts supported
6318 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6319 (386bsd is not well tested yet)
6320 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6322 * New file formats supported
6324 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6325 supports reading of `a.out.adobe' object files, which are an a.out
6326 format extended with minimal information about multiple sections.
6330 `show copying' is the same as the old `info copying'.
6331 `show warranty' is the same as `info warrantee'.
6332 These were renamed for consistency. The old commands continue to work.
6334 `info handle' is a new alias for `info signals'.
6336 You can now define pre-command hooks, which attach arbitrary command
6337 scripts to any command. The commands in the hook will be executed
6338 prior to the user's command. You can also create a hook which will be
6339 executed whenever the program stops. See gdb.texinfo.
6343 We now deal with Cfront style name mangling, and can even extract type
6344 info from mangled symbols. GDB can automatically figure out which
6345 symbol mangling style your C++ compiler uses.
6347 Calling of methods and virtual functions has been improved as well.
6351 The crash that occured when debugging Sun Ansi-C compiled binaries is
6352 fixed. This was due to mishandling of the extra N_SO stabs output
6355 We also finally got Ultrix 4.2 running in house, and fixed core file
6356 support, with help from a dozen people on the net.
6358 John M. Farrell discovered that the reason that single-stepping was so
6359 slow on all of the Mips based platforms (primarily SGI and DEC) was
6360 that we were trying to demangle and lookup a symbol used for internal
6361 purposes on every instruction that was being stepped through. Changing
6362 the name of that symbol so that it couldn't be mistaken for a C++
6363 mangled symbol sped things up a great deal.
6365 Rich Pixley sped up symbol lookups in general by getting much smarter
6366 about when C++ symbol mangling is necessary. This should make symbol
6367 completion (TAB on the command line) much faster. It's not as fast as
6368 we'd like, but it's significantly faster than gdb-4.6.
6372 A new user controllable variable 'call_scratch_address' can
6373 specify the location of a scratch area to be used when GDB
6374 calls a function in the target. This is necessary because the
6375 usual method of putting the scratch area on the stack does not work
6376 in systems that have separate instruction and data spaces.
6378 We integrated changes to support the 29k UDI (Universal Debugger
6379 Interface), but discovered at the last minute that we didn't have all
6380 of the appropriate copyright paperwork. We are working with AMD to
6381 resolve this, and hope to have it available soon.
6385 We have sped up the remote serial line protocol, especially for targets
6386 with lots of registers. It now supports a new `expedited status' ('T')
6387 message which can be used in place of the existing 'S' status message.
6388 This allows the remote stub to send only the registers that GDB
6389 needs to make a quick decision about single-stepping or conditional
6390 breakpoints, eliminating the need to fetch the entire register set for
6391 each instruction being stepped through.
6393 The GDB remote serial protocol now implements a write-through cache for
6394 registers, only re-reading the registers if the target has run.
6396 There is also a new remote serial stub for SPARC processors. You can
6397 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6398 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6399 processor with a serial port.
6403 Configure.in files have become much easier to read and modify. A new
6404 `table driven' format makes it more obvious what configurations are
6405 supported, and what files each one uses.
6409 There is a new opcodes library which will eventually contain all of the
6410 disassembly routines and opcode tables. At present, it only contains
6411 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6412 disassembler (binutils/objdump) to share these routines.
6414 The libiberty library is now copylefted under the GNU Library General
6415 Public License. This allows more liberal use, and was done so libg++
6416 can use it. This makes no difference to GDB, since the Library License
6417 grants all the rights from the General Public License.
6421 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6422 reference to the stabs symbol info used by the debugger. It is (as far
6423 as we know) the only published document on this fascinating topic. We
6424 encourage you to read it, compare it to the stabs information on your
6425 system, and send improvements on the document in general (to
6426 bug-gdb@prep.ai.mit.edu).
6428 And, of course, many bugs have been fixed.
6431 *** Changes in GDB-4.6:
6433 * Better support for C++ function names
6435 GDB now accepts as input the "demangled form" of C++ overloaded function
6436 names and member function names, and can do command completion on such names
6437 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6438 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6439 Make use of command completion, it is your friend.
6441 GDB also now accepts a variety of C++ mangled symbol formats. They are
6442 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6443 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6444 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6445 for the list of formats.
6447 * G++ symbol mangling problem
6449 Recent versions of gcc have a bug in how they emit debugging information for
6450 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6451 directory) can be applied to gcc to fix the problem. Alternatively, if you
6452 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6453 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6454 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6457 * New 'maintenance' command
6459 All of the commands related to hacking GDB internals have been moved out of
6460 the main command set, and now live behind the 'maintenance' command. This
6461 can also be abbreviated as 'mt'. The following changes were made:
6463 dump-me -> maintenance dump-me
6464 info all-breakpoints -> maintenance info breakpoints
6465 printmsyms -> maintenance print msyms
6466 printobjfiles -> maintenance print objfiles
6467 printpsyms -> maintenance print psymbols
6468 printsyms -> maintenance print symbols
6470 The following commands are new:
6472 maintenance demangle Call internal GDB demangler routine to
6473 demangle a C++ link name and prints the result.
6474 maintenance print type Print a type chain for a given symbol
6476 * Change to .gdbinit file processing
6478 We now read the $HOME/.gdbinit file before processing the argv arguments
6479 (e.g. reading symbol files or core files). This allows global parameters to
6480 be set, which will apply during the symbol reading. The ./.gdbinit is still
6481 read after argv processing.
6483 * New hosts supported
6485 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6487 GNU/Linux support i386-unknown-linux or linux
6489 We are also including code to support the HP/PA running BSD and HPUX. This
6490 is almost guaranteed not to work, as we didn't have time to test or build it
6491 for this release. We are including it so that the more adventurous (or
6492 masochistic) of you can play with it. We also had major problems with the
6493 fact that the compiler that we got from HP doesn't support the -g option.
6496 * New targets supported
6498 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6500 * More smarts about finding #include files
6502 GDB now remembers the compilation directory for all include files, and for
6503 all files from which C is generated (like yacc and lex sources). This
6504 greatly improves GDB's ability to find yacc/lex sources, and include files,
6505 especially if you are debugging your program from a directory different from
6506 the one that contains your sources.
6508 We also fixed a bug which caused difficulty with listing and setting
6509 breakpoints in include files which contain C code. (In the past, you had to
6510 try twice in order to list an include file that you hadn't looked at before.)
6512 * Interesting infernals change
6514 GDB now deals with arbitrary numbers of sections, where the symbols for each
6515 section must be relocated relative to that section's landing place in the
6516 target's address space. This work was needed to support ELF with embedded
6517 stabs used by Solaris-2.0.
6519 * Bug fixes (of course!)
6521 There have been loads of fixes for the following things:
6522 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6523 i960, stabs, DOS(GO32), procfs, etc...
6525 See the ChangeLog for details.
6527 *** Changes in GDB-4.5:
6529 * New machines supported (host and target)
6531 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6533 SGI Irix-4.x mips-sgi-irix4 or iris4
6535 * New malloc package
6537 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6538 Mmalloc is capable of handling mutiple heaps of memory. It is also
6539 capable of saving a heap to a file, and then mapping it back in later.
6540 This can be used to greatly speedup the startup of GDB by using a
6541 pre-parsed symbol table which lives in a mmalloc managed heap. For
6542 more details, please read mmalloc/mmalloc.texi.
6546 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6547 'help info proc' for details.
6549 * MIPS ecoff symbol table format
6551 The code that reads MIPS symbol table format is now supported on all hosts.
6552 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6555 * File name changes for MS-DOS
6557 Many files in the config directories have been renamed to make it easier to
6558 support GDB on MS-DOSe systems (which have very restrictive file name
6559 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6560 environment) is close to working but has some remaining problems. Note
6561 that debugging of DOS programs is not supported, due to limitations
6562 in the ``operating system'', but it can be used to host cross-debugging.
6564 * Cross byte order fixes
6566 Many fixes have been made to support cross debugging of Sparc and MIPS
6567 targets from hosts whose byte order differs.
6569 * New -mapped and -readnow options
6571 If memory-mapped files are available on your system through the 'mmap'
6572 system call, you can use the -mapped option on the `file' or
6573 `symbol-file' commands to cause GDB to write the symbols from your
6574 program into a reusable file. If the program you are debugging is
6575 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6576 Future GDB debugging sessions will notice the presence of this file,
6577 and will quickly map in symbol information from it, rather than reading
6578 the symbol table from the executable program. Using the '-mapped'
6579 option in a GDB `file' or `symbol-file' command has the same effect as
6580 starting GDB with the '-mapped' command-line option.
6582 You can cause GDB to read the entire symbol table immediately by using
6583 the '-readnow' option with any of the commands that load symbol table
6584 information (or on the GDB command line). This makes the command
6585 slower, but makes future operations faster.
6587 The -mapped and -readnow options are typically combined in order to
6588 build a `fred.syms' file that contains complete symbol information.
6589 A simple GDB invocation to do nothing but build a `.syms' file for future
6592 gdb -batch -nx -mapped -readnow programname
6594 The `.syms' file is specific to the host machine on which GDB is run.
6595 It holds an exact image of GDB's internal symbol table. It cannot be
6596 shared across multiple host platforms.
6598 * longjmp() handling
6600 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6601 siglongjmp() without losing control. This feature has not yet been ported to
6602 all systems. It currently works on many 386 platforms, all MIPS-based
6603 platforms (SGI, DECstation, etc), and Sun3/4.
6607 Preliminary work has been put in to support the new Solaris OS from Sun. At
6608 this time, it can control and debug processes, but it is not capable of
6613 As always, many many bug fixes. The major areas were with g++, and mipsread.
6614 People using the MIPS-based platforms should experience fewer mysterious
6615 crashes and trashed symbol tables.
6617 *** Changes in GDB-4.4:
6619 * New machines supported (host and target)
6621 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6623 BSD Reno on Vax vax-dec-bsd
6624 Ultrix on Vax vax-dec-ultrix
6626 * New machines supported (target)
6628 AMD 29000 embedded, using EBMON a29k-none-none
6632 GDB continues to improve its handling of C++. `References' work better.
6633 The demangler has also been improved, and now deals with symbols mangled as
6634 per the Annotated C++ Reference Guide.
6636 GDB also now handles `stabs' symbol information embedded in MIPS
6637 `ecoff' symbol tables. Since the ecoff format was not easily
6638 extensible to handle new languages such as C++, this appeared to be a
6639 good way to put C++ debugging info into MIPS binaries. This option
6640 will be supported in the GNU C compiler, version 2, when it is
6643 * New features for SVR4
6645 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6646 shared libraries. Debugging dynamically linked programs should present
6647 only minor differences from debugging statically linked programs.
6649 The `info proc' command will print out information about any process
6650 on an SVR4 system (including the one you are debugging). At the moment,
6651 it prints the address mappings of the process.
6653 If you bring up GDB on another SVR4 system, please send mail to
6654 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6656 * Better dynamic linking support in SunOS
6658 Reading symbols from shared libraries which contain debugging symbols
6659 now works properly. However, there remain issues such as automatic
6660 skipping of `transfer vector' code during function calls, which
6661 make it harder to debug code in a shared library, than to debug the
6662 same code linked statically.
6666 GDB is now using the latest `getopt' routines from the FSF. This
6667 version accepts the -- prefix for options with long names. GDB will
6668 continue to accept the old forms (-option and +option) as well.
6669 Various single letter abbreviations for options have been explicity
6670 added to the option table so that they won't get overshadowed in the
6671 future by other options that begin with the same letter.
6675 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6676 Many assorted bugs have been handled. Many more remain to be handled.
6677 See the various ChangeLog files (primarily in gdb and bfd) for details.
6680 *** Changes in GDB-4.3:
6682 * New machines supported (host and target)
6684 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6685 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6686 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6688 * Almost SCO Unix support
6690 We had hoped to support:
6691 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6692 (except for core file support), but we discovered very late in the release
6693 that it has problems with process groups that render gdb unusable. Sorry
6694 about that. I encourage people to fix it and post the fixes.
6696 * Preliminary ELF and DWARF support
6698 GDB can read ELF object files on System V Release 4, and can handle
6699 debugging records for C, in DWARF format, in ELF files. This support
6700 is preliminary. If you bring up GDB on another SVR4 system, please
6701 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6706 GDB now uses the latest `readline' library. One user-visible change
6707 is that two tabs will list possible command completions, which previously
6708 required typing M-? (meta-question mark, or ESC ?).
6712 The `stepi' bug that many of you noticed has been squashed.
6713 Many bugs in C++ have been handled. Many more remain to be handled.
6714 See the various ChangeLog files (primarily in gdb and bfd) for details.
6716 * State of the MIPS world (in case you wondered):
6718 GDB can understand the symbol tables emitted by the compilers
6719 supplied by most vendors of MIPS-based machines, including DEC. These
6720 symbol tables are in a format that essentially nobody else uses.
6722 Some versions of gcc come with an assembler post-processor called
6723 mips-tfile. This program is required if you want to do source-level
6724 debugging of gcc-compiled programs. I believe FSF does not ship
6725 mips-tfile with gcc version 1, but it will eventually come with gcc
6728 Debugging of g++ output remains a problem. g++ version 1.xx does not
6729 really support it at all. (If you're lucky, you should be able to get
6730 line numbers and stack traces to work, but no parameters or local
6731 variables.) With some work it should be possible to improve the
6734 When gcc version 2 is released, you will have somewhat better luck.
6735 However, even then you will get confusing results for inheritance and
6738 We will eventually provide full debugging of g++ output on
6739 DECstations. This will probably involve some kind of stabs-in-ecoff
6740 encapulation, but the details have not been worked out yet.
6743 *** Changes in GDB-4.2:
6745 * Improved configuration
6747 Only one copy of `configure' exists now, and it is not self-modifying.
6748 Porting BFD is simpler.
6752 The `step' and `next' commands now only stop at the first instruction
6753 of a source line. This prevents the multiple stops that used to occur
6754 in switch statements, for-loops, etc. `Step' continues to stop if a
6755 function that has debugging information is called within the line.
6759 Lots of small bugs fixed. More remain.
6761 * New host supported (not target)
6763 Intel 386 PC clone running Mach i386-none-mach
6766 *** Changes in GDB-4.1:
6768 * Multiple source language support
6770 GDB now has internal scaffolding to handle several source languages.
6771 It determines the type of each source file from its filename extension,
6772 and will switch expression parsing and number formatting to match the
6773 language of the function in the currently selected stack frame.
6774 You can also specifically set the language to be used, with
6775 `set language c' or `set language modula-2'.
6779 GDB now has preliminary support for the GNU Modula-2 compiler,
6780 currently under development at the State University of New York at
6781 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6782 continue through the fall of 1991 and into 1992.
6784 Other Modula-2 compilers are currently not supported, and attempting to
6785 debug programs compiled with them will likely result in an error as the
6786 symbol table is read. Feel free to work on it, though!
6788 There are hooks in GDB for strict type checking and range checking,
6789 in the `Modula-2 philosophy', but they do not currently work.
6793 GDB can now write to executable and core files (e.g. patch
6794 a variable's value). You must turn this switch on, specify
6795 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6796 by assigning a new value to a variable. Modifications take
6799 * Automatic SunOS shared library reading
6801 When you run your program, GDB automatically determines where its
6802 shared libraries (if any) have been loaded, and reads their symbols.
6803 The `share' command is no longer needed. This also works when
6804 examining core files.
6808 You can specify the number of lines that the `list' command shows.
6811 * New machines supported (host and target)
6813 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6814 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6815 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6817 * New hosts supported (not targets)
6819 IBM RT/PC: romp-ibm-aix or rtpc
6821 * New targets supported (not hosts)
6823 AMD 29000 embedded with COFF a29k-none-coff
6824 AMD 29000 embedded with a.out a29k-none-aout
6825 Ultracomputer remote kernel debug a29k-nyu-kern
6827 * New remote interfaces
6833 *** Changes in GDB-4.0:
6837 Wide output is wrapped at good places to make the output more readable.
6839 Gdb now supports cross-debugging from a host machine of one type to a
6840 target machine of another type. Communication with the target system
6841 is over serial lines. The ``target'' command handles connecting to the
6842 remote system; the ``load'' command will download a program into the
6843 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6844 also supports debugging of realtime processes running under VxWorks,
6845 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6846 stub on the target system.
6848 New CPUs supported include the AMD 29000 and Intel 960.
6850 GDB now reads object files and symbol tables via a ``binary file''
6851 library, which allows a single copy of GDB to debug programs of multiple
6852 object file types such as a.out and coff.
6854 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6855 refcard.dvi and refcard.ps are available to format it).
6858 * Control-Variable user interface simplified
6860 All variables that control the operation of the debugger can be set
6861 by the ``set'' command, and displayed by the ``show'' command.
6863 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6864 ``Show prompt'' produces the response:
6865 Gdb's prompt is new-gdb=>.
6867 What follows are the NEW set commands. The command ``help set'' will
6868 print a complete list of old and new set commands. ``help set FOO''
6869 will give a longer description of the variable FOO. ``show'' will show
6870 all of the variable descriptions and their current settings.
6872 confirm on/off: Enables warning questions for operations that are
6873 hard to recover from, e.g. rerunning the program while
6874 it is already running. Default is ON.
6876 editing on/off: Enables EMACS style command line editing
6877 of input. Previous lines can be recalled with
6878 control-P, the current line can be edited with control-B,
6879 you can search for commands with control-R, etc.
6882 history filename NAME: NAME is where the gdb command history
6883 will be stored. The default is .gdb_history,
6884 or the value of the environment variable
6887 history size N: The size, in commands, of the command history. The
6888 default is 256, or the value of the environment variable
6891 history save on/off: If this value is set to ON, the history file will
6892 be saved after exiting gdb. If set to OFF, the
6893 file will not be saved. The default is OFF.
6895 history expansion on/off: If this value is set to ON, then csh-like
6896 history expansion will be performed on
6897 command line input. The default is OFF.
6899 radix N: Sets the default radix for input and output. It can be set
6900 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6901 in the current radix, so "set radix 10" is always a no-op.
6903 height N: This integer value is the number of lines on a page. Default
6904 is 24, the current `stty rows'' setting, or the ``li#''
6905 setting from the termcap entry matching the environment
6908 width N: This integer value is the number of characters on a line.
6909 Default is 80, the current `stty cols'' setting, or the ``co#''
6910 setting from the termcap entry matching the environment
6913 Note: ``set screensize'' is obsolete. Use ``set height'' and
6914 ``set width'' instead.
6916 print address on/off: Print memory addresses in various command displays,
6917 such as stack traces and structure values. Gdb looks
6918 more ``symbolic'' if you turn this off; it looks more
6919 ``machine level'' with it on. Default is ON.
6921 print array on/off: Prettyprint arrays. New convenient format! Default
6924 print demangle on/off: Print C++ symbols in "source" form if on,
6927 print asm-demangle on/off: Same, for assembler level printouts
6930 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6933 * Support for Epoch Environment.
6935 The epoch environment is a version of Emacs v18 with windowing. One
6936 new command, ``inspect'', is identical to ``print'', except that if you
6937 are running in the epoch environment, the value is printed in its own
6941 * Support for Shared Libraries
6943 GDB can now debug programs and core files that use SunOS shared libraries.
6944 Symbols from a shared library cannot be referenced
6945 before the shared library has been linked with the program (this
6946 happens after you type ``run'' and before the function main() is entered).
6947 At any time after this linking (including when examining core files
6948 from dynamically linked programs), gdb reads the symbols from each
6949 shared library when you type the ``sharedlibrary'' command.
6950 It can be abbreviated ``share''.
6952 sharedlibrary REGEXP: Load shared object library symbols for files
6953 matching a unix regular expression. No argument
6954 indicates to load symbols for all shared libraries.
6956 info sharedlibrary: Status of loaded shared libraries.
6961 A watchpoint stops execution of a program whenever the value of an
6962 expression changes. Checking for this slows down execution
6963 tremendously whenever you are in the scope of the expression, but is
6964 quite useful for catching tough ``bit-spreader'' or pointer misuse
6965 problems. Some machines such as the 386 have hardware for doing this
6966 more quickly, and future versions of gdb will use this hardware.
6968 watch EXP: Set a watchpoint (breakpoint) for an expression.
6970 info watchpoints: Information about your watchpoints.
6972 delete N: Deletes watchpoint number N (same as breakpoints).
6973 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6974 enable N: Re-enables watchpoint number N (same as breakpoints).
6977 * C++ multiple inheritance
6979 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6982 * C++ exception handling
6984 Gdb now supports limited C++ exception handling. Besides the existing
6985 ability to breakpoint on an exception handler, gdb can breakpoint on
6986 the raising of an exception (before the stack is peeled back to the
6989 catch FOO: If there is a FOO exception handler in the dynamic scope,
6990 set a breakpoint to catch exceptions which may be raised there.
6991 Multiple exceptions (``catch foo bar baz'') may be caught.
6993 info catch: Lists all exceptions which may be caught in the
6994 current stack frame.
6997 * Minor command changes
6999 The command ``call func (arg, arg, ...)'' now acts like the print
7000 command, except it does not print or save a value if the function's result
7001 is void. This is similar to dbx usage.
7003 The ``up'' and ``down'' commands now always print the frame they end up
7004 at; ``up-silently'' and `down-silently'' can be used in scripts to change
7005 frames without printing.
7007 * New directory command
7009 'dir' now adds directories to the FRONT of the source search path.
7010 The path starts off empty. Source files that contain debug information
7011 about the directory in which they were compiled can be found even
7012 with an empty path; Sun CC and GCC include this information. If GDB can't
7013 find your source file in the current directory, type "dir .".
7015 * Configuring GDB for compilation
7017 For normal use, type ``./configure host''. See README or gdb.texinfo
7020 GDB now handles cross debugging. If you are remotely debugging between
7021 two different machines, type ``./configure host -target=targ''.
7022 Host is the machine where GDB will run; targ is the machine
7023 where the program that you are debugging will run.