1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 8.2
6 * GDB and GDBserver now support IPv6 connections. IPv6 addresses
7 can be passed using the '[ADDRESS]:PORT' notation, or the regular
12 frame apply [all | COUNT | -COUNT | level LEVEL...] [FLAG]... COMMAND
13 Apply a command to some frames.
14 FLAG arguments allow to control what output to produce and how to handle
15 errors raised when applying COMMAND to a frame.
18 Apply a command to all threads (ignoring errors and empty output).
19 Shortcut for 'thread apply all -s COMMAND'.
22 Apply a command to all frames (ignoring errors and empty output).
23 Shortcut for 'frame apply all -s COMMAND'.
26 Apply a command to all frames of all threads (ignoring errors and empty
28 Shortcut for 'thread apply all -s frame apply all -s COMMAND'.
32 thread apply [all | COUNT | -COUNT] [FLAG]... COMMAND
33 The 'thread apply' command accepts new FLAG arguments.
34 FLAG arguments allow to control what output to produce and how to handle
35 errors raised when applying COMMAND to a thread.
37 *** Changes in GDB 8.2
39 * The 'set disassembler-options' command now supports specifying options
42 * The 'symbol-file' command now accepts an '-o' option to add a relative
43 offset to all sections.
45 * Similarly, the 'add-symbol-file' command also accepts an '-o' option to add
46 a relative offset to all sections, but it allows to override the load
47 address of individual sections using '-s'.
49 * The 'add-symbol-file' command no longer requires the second argument
50 (address of the text section).
52 * The endianness used with the 'set endian auto' mode in the absence of
53 an executable selected for debugging is now the last endianness chosen
54 either by one of the 'set endian big' and 'set endian little' commands
55 or by inferring from the last executable used, rather than the startup
58 * The pager now allows a "c" response, meaning to disable the pager
59 for the rest of the current command.
61 * The commands 'info variables/functions/types' now show the source line
62 numbers of symbol definitions when available.
64 * 'info proc' now works on running processes on FreeBSD systems and core
65 files created on FreeBSD systems.
67 * C expressions can now use _Alignof, and C++ expressions can now use
74 Control display of debugging info regarding the FreeBSD native target.
76 set|show varsize-limit
77 This new setting allows the user to control the maximum size of Ada
78 objects being printed when those objects have a variable type,
79 instead of that maximum size being hardcoded to 65536 bytes.
81 set|show record btrace cpu
82 Controls the processor to be used for enabling errata workarounds for
85 maint check libthread-db
86 Run integrity checks on the current inferior's thread debugging
89 maint set check-libthread-db (on|off)
90 maint show check-libthread-db
91 Control whether to run integrity checks on inferior specific thread
92 debugging libraries as they are loaded. The default is not to
97 ** Type alignment is now exposed via the "align" attribute of a gdb.Type.
99 ** The commands attached to a breakpoint can be set by assigning to
100 the breakpoint's "commands" field.
102 ** gdb.execute can now execute multi-line gdb commands.
104 ** The new functions gdb.convenience_variable and
105 gdb.set_convenience_variable can be used to get and set the value
106 of convenience variables.
108 ** A gdb.Parameter will no longer print the "set" help text on an
109 ordinary "set"; instead by default a "set" will be silent unless
110 the get_set_string method returns a non-empty string.
114 RiscV ELF riscv*-*-elf
116 * Removed targets and native configurations
118 m88k running OpenBSD m88*-*-openbsd*
119 SH-5/SH64 ELF sh64-*-elf*, SH-5/SH64 support in sh*
120 SH-5/SH64 running GNU/Linux SH-5/SH64 support in sh*-*-linux*
121 SH-5/SH64 running OpenBSD SH-5/SH64 support in sh*-*-openbsd*
123 * Aarch64/Linux hardware watchpoints improvements
125 Hardware watchpoints on unaligned addresses are now properly
126 supported when running Linux kernel 4.10 or higher: read and access
127 watchpoints are no longer spuriously missed, and all watchpoints
128 lengths between 1 and 8 bytes are supported. On older kernels,
129 watchpoints set on unaligned addresses are no longer missed, with
130 the tradeoff that there is a possibility of false hits being
133 * New configure options
135 --enable-codesign=CERT
136 This can be used to invoke "codesign -s CERT" after building gdb.
137 This option is useful on macOS, where code signing is required for
138 gdb to work properly.
140 *** Changes in GDB 8.1
142 * GDB now supports dynamically creating arbitrary register groups specified
143 in XML target descriptions. This allows for finer grain grouping of
144 registers on systems with a large amount of registers.
146 * The 'ptype' command now accepts a '/o' flag, which prints the
147 offsets and sizes of fields in a struct, like the pahole(1) tool.
149 * New "--readnever" command line option instructs GDB to not read each
150 symbol file's symbolic debug information. This makes startup faster
151 but at the expense of not being able to perform symbolic debugging.
152 This option is intended for use cases where symbolic debugging will
153 not be used, e.g., when you only need to dump the debuggee's core.
155 * GDB now uses the GNU MPFR library, if available, to emulate target
156 floating-point arithmetic during expression evaluation when the target
157 uses different floating-point formats than the host. At least version
158 3.1 of GNU MPFR is required.
160 * GDB now supports access to the guarded-storage-control registers and the
161 software-based guarded-storage broadcast control registers on IBM z14.
163 * On Unix systems, GDB now supports transmitting environment variables
164 that are to be set or unset to GDBserver. These variables will
165 affect the environment to be passed to the remote inferior.
167 To inform GDB of environment variables that are to be transmitted to
168 GDBserver, use the "set environment" command. Only user set
169 environment variables are sent to GDBserver.
171 To inform GDB of environment variables that are to be unset before
172 the remote inferior is started by the GDBserver, use the "unset
173 environment" command.
175 * Completion improvements
177 ** GDB can now complete function parameters in linespecs and
178 explicit locations without quoting. When setting breakpoints,
179 quoting around functions names to help with TAB-completion is
180 generally no longer necessary. For example, this now completes
183 (gdb) b function(in[TAB]
184 (gdb) b function(int)
186 Related, GDB is no longer confused with completing functions in
187 C++ anonymous namespaces:
190 (gdb) b (anonymous namespace)::[TAB][TAB]
191 (anonymous namespace)::a_function()
192 (anonymous namespace)::b_function()
194 ** GDB now has much improved linespec and explicit locations TAB
195 completion support, that better understands what you're
196 completing and offers better suggestions. For example, GDB no
197 longer offers data symbols as possible completions when you're
198 setting a breakpoint.
200 ** GDB now TAB-completes label symbol names.
202 ** The "complete" command now mimics TAB completion accurately.
204 * New command line options (gcore)
207 Dump all memory mappings.
209 * Breakpoints on C++ functions are now set on all scopes by default
211 By default, breakpoints on functions/methods are now interpreted as
212 specifying all functions with the given name ignoring missing
213 leading scopes (namespaces and classes).
215 For example, assuming a C++ program with symbols named:
220 both commands "break func()" and "break B::func()" set a breakpoint
223 You can use the new flag "-qualified" to override this. This makes
224 GDB interpret the specified function name as a complete
225 fully-qualified name instead. For example, using the same C++
226 program, the "break -q B::func" command sets a breakpoint on
227 "B::func", only. A parameter has been added to the Python
228 gdb.Breakpoint constructor to achieve the same result when creating
229 a breakpoint from Python.
231 * Breakpoints on functions marked with C++ ABI tags
233 GDB can now set breakpoints on functions marked with C++ ABI tags
234 (e.g., [abi:cxx11]). See here for a description of ABI tags:
235 https://developers.redhat.com/blog/2015/02/05/gcc5-and-the-c11-abi/
237 Functions with a C++11 abi tag are demangled/displayed like this:
239 function[abi:cxx11](int)
242 You can now set a breakpoint on such functions simply as if they had
245 (gdb) b function(int)
247 Or if you need to disambiguate between tags, like:
249 (gdb) b function[abi:other_tag](int)
251 Tab completion was adjusted accordingly as well.
255 ** New events gdb.new_inferior, gdb.inferior_deleted, and
256 gdb.new_thread are emitted. See the manual for further
257 description of these.
259 ** A new function, "gdb.rbreak" has been added to the Python API.
260 This function allows the setting of a large number of breakpoints
261 via a regex pattern in Python. See the manual for further details.
263 ** Python breakpoints can now accept explicit locations. See the
264 manual for a further description of this feature.
267 * New features in the GDB remote stub, GDBserver
269 ** GDBserver is now able to start inferior processes with a
270 specified initial working directory.
272 The user can set the desired working directory to be used from
273 GDB using the new "set cwd" command.
275 ** New "--selftest" command line option runs some GDBserver self
276 tests. These self tests are disabled in releases.
278 ** On Unix systems, GDBserver now does globbing expansion and variable
279 substitution in inferior command line arguments.
281 This is done by starting inferiors using a shell, like GDB does.
282 See "set startup-with-shell" in the user manual for how to disable
283 this from GDB when using "target extended-remote". When using
284 "target remote", you can disable the startup with shell by using the
285 new "--no-startup-with-shell" GDBserver command line option.
287 ** On Unix systems, GDBserver now supports receiving environment
288 variables that are to be set or unset from GDB. These variables
289 will affect the environment to be passed to the inferior.
291 * When catching an Ada exception raised with a message, GDB now prints
292 the message in the catchpoint hit notification. In GDB/MI mode, that
293 information is provided as an extra field named "exception-message"
294 in the *stopped notification.
296 * Trait objects can now be inspected When debugging Rust code. This
297 requires compiler support which will appear in Rust 1.24.
301 QEnvironmentHexEncoded
302 Inform GDBserver of an environment variable that is to be passed to
303 the inferior when starting it.
306 Inform GDBserver of an environment variable that is to be unset
307 before starting the remote inferior.
310 Inform GDBserver that the environment should be reset (i.e.,
311 user-set environment variables should be unset).
314 Indicates whether the inferior must be started with a shell or not.
317 Tell GDBserver that the inferior to be started should use a specific
320 * The "maintenance print c-tdesc" command now takes an optional
321 argument which is the file name of XML target description.
323 * The "maintenance selftest" command now takes an optional argument to
324 filter the tests to be run.
326 * The "enable", and "disable" commands now accept a range of
327 breakpoint locations, e.g. "enable 1.3-5".
332 Set and show the current working directory for the inferior.
335 Set and show compilation command used for compiling and injecting code
336 with the 'compile' commands.
338 set debug separate-debug-file
339 show debug separate-debug-file
340 Control the display of debug output about separate debug file search.
342 set dump-excluded-mappings
343 show dump-excluded-mappings
344 Control whether mappings marked with the VM_DONTDUMP flag should be
345 dumped when generating a core file.
348 List the registered selftests.
351 Start the debugged program stopping at the first instruction.
354 Control display of debugging messages related to OpenRISC targets.
356 set|show print type nested-type-limit
357 Set and show the limit of nesting level for nested types that the
358 type printer will show.
360 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
363 * Safer/improved support for debugging with no debug info
365 GDB no longer assumes functions with no debug information return
368 This means that GDB now refuses to call such functions unless you
369 tell it the function's type, by either casting the call to the
370 declared return type, or by casting the function to a function
371 pointer of the right type, and calling that:
373 (gdb) p getenv ("PATH")
374 'getenv' has unknown return type; cast the call to its declared return type
375 (gdb) p (char *) getenv ("PATH")
376 $1 = 0x7fffffffe "/usr/local/bin:/"...
377 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
378 $2 = 0x7fffffffe "/usr/local/bin:/"...
380 Similarly, GDB no longer assumes that global variables with no debug
381 info have type 'int', and refuses to print the variable's value
382 unless you tell it the variable's type:
385 'var' has unknown type; cast it to its declared type
389 * New native configurations
391 FreeBSD/aarch64 aarch64*-*-freebsd*
392 FreeBSD/arm arm*-*-freebsd*
396 FreeBSD/aarch64 aarch64*-*-freebsd*
397 FreeBSD/arm arm*-*-freebsd*
398 OpenRISC ELF or1k*-*-elf
400 * Removed targets and native configurations
402 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
404 *** Changes in GDB 8.0
406 * GDB now supports access to the PKU register on GNU/Linux. The register is
407 added by the Memory Protection Keys for Userspace feature which will be
408 available in future Intel CPUs.
410 * GDB now supports C++11 rvalue references.
414 ** New functions to start, stop and access a running btrace recording.
415 ** Rvalue references are now supported in gdb.Type.
417 * GDB now supports recording and replaying rdrand and rdseed Intel 64
420 * Building GDB and GDBserver now requires a C++11 compiler.
422 For example, GCC 4.8 or later.
424 It is no longer possible to build GDB or GDBserver with a C
425 compiler. The --disable-build-with-cxx configure option has been
428 * Building GDB and GDBserver now requires GNU make >= 3.81.
430 It is no longer supported to build GDB or GDBserver with another
431 implementation of the make program or an earlier version of GNU make.
433 * Native debugging on MS-Windows supports command-line redirection
435 Command-line arguments used for starting programs on MS-Windows can
436 now include redirection symbols supported by native Windows shells,
437 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
438 as "run", "start", and "set args", as well as the corresponding MI
441 * Support for thread names on MS-Windows.
443 GDB now catches and handles the special exception that programs
444 running on MS-Windows use to assign names to threads in the
447 * Support for Java programs compiled with gcj has been removed.
449 * User commands now accept an unlimited number of arguments.
450 Previously, only up to 10 was accepted.
452 * The "eval" command now expands user-defined command arguments.
454 This makes it easier to process a variable number of arguments:
459 eval "print $arg%d", $i
464 * Target descriptions can now describe registers for sparc32 and sparc64.
466 * GDB now supports DWARF version 5 (debug information format).
467 Its .debug_names index is not yet supported.
469 * New native configurations
471 FreeBSD/mips mips*-*-freebsd
475 Synopsys ARC arc*-*-elf32
476 FreeBSD/mips mips*-*-freebsd
478 * Removed targets and native configurations
480 Alpha running FreeBSD alpha*-*-freebsd*
481 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
486 Erases all the flash memory regions reported by the target.
488 maint print arc arc-instruction address
489 Print internal disassembler information about instruction at a given address.
493 set disassembler-options
494 show disassembler-options
495 Controls the passing of target specific information to the disassembler.
496 If it is necessary to specify more than one disassembler option then
497 multiple options can be placed together into a comma separated list.
498 The default value is the empty string. Currently, the only supported
499 targets are ARM, PowerPC and S/390.
504 Erases all the flash memory regions reported by the target. This is
505 equivalent to the CLI command flash-erase.
507 -file-list-shared-libraries
508 List the shared libraries in the program. This is
509 equivalent to the CLI command "info shared".
512 Catchpoints stopping the program when Ada exceptions are
513 handled. This is equivalent to the CLI command "catch handlers".
515 *** Changes in GDB 7.12
517 * GDB and GDBserver now build with a C++ compiler by default.
519 The --enable-build-with-cxx configure option is now enabled by
520 default. One must now explicitly configure with
521 --disable-build-with-cxx in order to build with a C compiler. This
522 option will be removed in a future release.
524 * GDBserver now supports recording btrace without maintaining an active
527 * GDB now supports a negative repeat count in the 'x' command to examine
528 memory backward from the given address. For example:
531 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
532 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
533 (gdb) x/-5i 0x0000000000400580
534 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
535 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
536 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
537 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
538 0x40057b <main(int, char**)+25>:
539 callq 0x400536 <Func1(int, char const*)>
541 * Fortran: Support structures with fields of dynamic types and
542 arrays of dynamic types.
544 * The symbol dumping maintenance commands have new syntax.
545 maint print symbols [-pc address] [--] [filename]
546 maint print symbols [-objfile objfile] [-source source] [--] [filename]
547 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
548 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
549 maint print msymbols [-objfile objfile] [--] [filename]
551 * GDB now supports multibit bitfields and enums in target register
554 * New Python-based convenience function $_as_string(val), which returns
555 the textual representation of a value. This function is especially
556 useful to obtain the text label of an enum value.
558 * Intel MPX bound violation handling.
560 Segmentation faults caused by a Intel MPX boundary violation
561 now display the kind of violation (upper or lower), the memory
562 address accessed and the memory bounds, along with the usual
563 signal received and code location.
567 Program received signal SIGSEGV, Segmentation fault
568 Upper bound violation while accessing address 0x7fffffffc3b3
569 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
570 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
572 * Rust language support.
573 GDB now supports debugging programs written in the Rust programming
574 language. See https://www.rust-lang.org/ for more information about
577 * Support for running interpreters on specified input/output devices
579 GDB now supports a new mechanism that allows frontends to provide
580 fully featured GDB console views, as a better alternative to
581 building such views on top of the "-interpreter-exec console"
582 command. See the new "new-ui" command below. With that command,
583 frontends can now start GDB in the traditional command-line mode
584 running in an embedded terminal emulator widget, and create a
585 separate MI interpreter running on a specified i/o device. In this
586 way, GDB handles line editing, history, tab completion, etc. in the
587 console all by itself, and the GUI uses the separate MI interpreter
588 for its own control and synchronization, invisible to the command
591 * The "catch syscall" command catches groups of related syscalls.
593 The "catch syscall" command now supports catching a group of related
594 syscalls using the 'group:' or 'g:' prefix.
599 skip -gfile file-glob-pattern
600 skip -function function
601 skip -rfunction regular-expression
602 A generalized form of the skip command, with new support for
603 glob-style file names and regular expressions for function names.
604 Additionally, a file spec and a function spec may now be combined.
606 maint info line-table REGEXP
607 Display the contents of GDB's internal line table data struture.
610 Run any GDB unit tests that were compiled in.
613 Start a new user interface instance running INTERP as interpreter,
614 using the TTY file for input/output.
618 ** gdb.Breakpoint objects have a new attribute "pending", which
619 indicates whether the breakpoint is pending.
620 ** Three new breakpoint-related events have been added:
621 gdb.breakpoint_created, gdb.breakpoint_modified, and
622 gdb.breakpoint_deleted.
625 Signal ("set") the given MS-Windows event object. This is used in
626 conjunction with the Windows JIT debugging (AeDebug) support, where
627 the OS suspends a crashing process until a debugger can attach to
628 it. Resuming the crashing process, in order to debug it, is done by
631 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
632 was added in GDBserver, including JIT compiling fast tracepoint's
633 conditional expression bytecode into native code.
635 * Support for various remote target protocols and ROM monitors has
638 target m32rsdi Remote M32R debugging over SDI
639 target mips MIPS remote debugging protocol
640 target pmon PMON ROM monitor
641 target ddb NEC's DDB variant of PMON for Vr4300
642 target rockhopper NEC RockHopper variant of PMON
643 target lsi LSI variant of PMO
645 * Support for tracepoints and fast tracepoints on powerpc-linux,
646 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
647 including JIT compiling fast tracepoint's conditional expression
648 bytecode into native code.
650 * MI async record =record-started now includes the method and format used for
651 recording. For example:
653 =record-started,thread-group="i1",method="btrace",format="bts"
655 * MI async record =thread-selected now includes the frame field. For example:
657 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
661 Andes NDS32 nds32*-*-elf
663 *** Changes in GDB 7.11
665 * GDB now supports debugging kernel-based threads on FreeBSD.
667 * Per-inferior thread numbers
669 Thread numbers are now per inferior instead of global. If you're
670 debugging multiple inferiors, GDB displays thread IDs using a
671 qualified INF_NUM.THR_NUM form. For example:
675 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
676 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
677 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
678 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
680 As consequence, thread numbers as visible in the $_thread
681 convenience variable and in Python's InferiorThread.num attribute
682 are no longer unique between inferiors.
684 GDB now maintains a second thread ID per thread, referred to as the
685 global thread ID, which is the new equivalent of thread numbers in
686 previous releases. See also $_gthread below.
688 For backwards compatibility, MI's thread IDs always refer to global
691 * Commands that accept thread IDs now accept the qualified
692 INF_NUM.THR_NUM form as well. For example:
695 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
698 * In commands that accept a list of thread IDs, you can now refer to
699 all threads of an inferior using a star wildcard. GDB accepts
700 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
701 refer to all threads of the current inferior. For example, "info
704 * You can use "info threads -gid" to display the global thread ID of
707 * The new convenience variable $_gthread holds the global number of
710 * The new convenience variable $_inferior holds the number of the
713 * GDB now displays the ID and name of the thread that hit a breakpoint
714 or received a signal, if your program is multi-threaded. For
717 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
718 Thread 1 "main" received signal SIGINT, Interrupt.
720 * Record btrace now supports non-stop mode.
722 * Support for tracepoints on aarch64-linux was added in GDBserver.
724 * The 'record instruction-history' command now indicates speculative execution
725 when using the Intel Processor Trace recording format.
727 * GDB now allows users to specify explicit locations, bypassing
728 the linespec parser. This feature is also available to GDB/MI
731 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
732 GDB now is able to debug both AArch64 applications and ARM applications
735 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
736 including JIT compiling fast tracepoint's conditional expression bytecode
739 * GDB now supports displaced stepping on AArch64 GNU/Linux.
741 * "info threads", "info inferiors", "info display", "info checkpoints"
742 and "maint info program-spaces" now list the corresponding items in
743 ascending ID order, for consistency with all other "info" commands.
745 * In Ada, the overloads selection menu has been enhanced to display the
746 parameter types and the return types for the matching overloaded subprograms.
750 maint set target-non-stop (on|off|auto)
751 maint show target-non-stop
752 Control whether GDB targets always operate in non-stop mode even if
753 "set non-stop" is "off". The default is "auto", meaning non-stop
754 mode is enabled if supported by the target.
756 maint set bfd-sharing
757 maint show bfd-sharing
758 Control the reuse of bfd objects.
762 Control display of debugging info regarding bfd caching.
766 Control display of debugging info regarding FreeBSD threads.
768 set remote multiprocess-extensions-packet
769 show remote multiprocess-extensions-packet
770 Set/show the use of the remote protocol multiprocess extensions.
772 set remote thread-events
773 show remote thread-events
774 Set/show the use of thread create/exit events.
776 set ada print-signatures on|off
777 show ada print-signatures"
778 Control whether parameter types and return types are displayed in overloads
779 selection menus. It is activaled (@code{on}) by default.
783 Controls the maximum size of memory, in bytes, that GDB will
784 allocate for value contents. Prevents incorrect programs from
785 causing GDB to allocate overly large buffers. Default is 64k.
787 * The "disassemble" command accepts a new modifier: /s.
788 It prints mixed source+disassembly like /m with two differences:
789 - disassembled instructions are now printed in program order, and
790 - and source for all relevant files is now printed.
791 The "/m" option is now considered deprecated: its "source-centric"
792 output hasn't proved useful in practice.
794 * The "record instruction-history" command accepts a new modifier: /s.
795 It behaves exactly like /m and prints mixed source+disassembly.
797 * The "set scheduler-locking" command supports a new mode "replay".
798 It behaves like "off" in record mode and like "on" in replay mode.
800 * Support for various ROM monitors has been removed:
802 target dbug dBUG ROM monitor for Motorola ColdFire
803 target picobug Motorola picobug monitor
804 target dink32 DINK32 ROM monitor for PowerPC
805 target m32r Renesas M32R/D ROM monitor
806 target mon2000 mon2000 ROM monitor
807 target ppcbug PPCBUG ROM monitor for PowerPC
809 * Support for reading/writing memory and extracting values on architectures
810 whose memory is addressable in units of any integral multiple of 8 bits.
813 Allows to break when an Ada exception is handled.
818 Indicates that an exec system call was executed.
820 exec-events feature in qSupported
821 The qSupported packet allows GDB to request support for exec
822 events using the new 'gdbfeature' exec-event, and the qSupported
823 response can contain the corresponding 'stubfeature'. Set and
824 show commands can be used to display whether these features are enabled.
827 Equivalent to interrupting with the ^C character, but works in
830 thread created stop reason (T05 create:...)
831 Indicates that the thread was just created and is stopped at entry.
833 thread exit stop reply (w exitcode;tid)
834 Indicates that the thread has terminated.
837 Enables/disables thread create and exit event reporting. For
838 example, this is used in non-stop mode when GDB stops a set of
839 threads and synchronously waits for the their corresponding stop
840 replies. Without exit events, if one of the threads exits, GDB
841 would hang forever not knowing that it should no longer expect a
842 stop for that same thread.
845 Indicates that there are no resumed threads left in the target (all
846 threads are stopped). The remote stub reports support for this stop
847 reply to GDB's qSupported query.
850 Enables/disables catching syscalls from the inferior process.
851 The remote stub reports support for this packet to GDB's qSupported query.
853 syscall_entry stop reason
854 Indicates that a syscall was just called.
856 syscall_return stop reason
857 Indicates that a syscall just returned.
859 * Extended-remote exec events
861 ** GDB now has support for exec events on extended-remote Linux targets.
862 For such targets with Linux kernels 2.5.46 and later, this enables
863 follow-exec-mode and exec catchpoints.
865 set remote exec-event-feature-packet
866 show remote exec-event-feature-packet
867 Set/show the use of the remote exec event feature.
869 * Thread names in remote protocol
871 The reply to qXfer:threads:read may now include a name attribute for each
874 * Target remote mode fork and exec events
876 ** GDB now has support for fork and exec events on target remote mode
877 Linux targets. For such targets with Linux kernels 2.5.46 and later,
878 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
879 fork and exec catchpoints.
881 * Remote syscall events
883 ** GDB now has support for catch syscall on remote Linux targets,
884 currently enabled on x86/x86_64 architectures.
886 set remote catch-syscall-packet
887 show remote catch-syscall-packet
888 Set/show the use of the remote catch syscall feature.
892 ** The -var-set-format command now accepts the zero-hexadecimal
893 format. It outputs data in hexadecimal format with zero-padding on the
898 ** gdb.InferiorThread objects have a new attribute "global_num",
899 which refers to the thread's global thread ID. The existing
900 "num" attribute now refers to the thread's per-inferior number.
901 See "Per-inferior thread numbers" above.
902 ** gdb.InferiorThread objects have a new attribute "inferior", which
903 is the Inferior object the thread belongs to.
905 *** Changes in GDB 7.10
907 * Support for process record-replay and reverse debugging on aarch64*-linux*
908 targets has been added. GDB now supports recording of A64 instruction set
909 including advance SIMD instructions.
911 * Support for Sun's version of the "stabs" debug file format has been removed.
913 * GDB now honors the content of the file /proc/PID/coredump_filter
914 (PID is the process ID) on GNU/Linux systems. This file can be used
915 to specify the types of memory mappings that will be included in a
916 corefile. For more information, please refer to the manual page of
917 "core(5)". GDB also has a new command: "set use-coredump-filter
918 on|off". It allows to set whether GDB will read the content of the
919 /proc/PID/coredump_filter file when generating a corefile.
921 * The "info os" command on GNU/Linux can now display information on
923 "info os cpus" Listing of all cpus/cores on the system
925 * GDB has two new commands: "set serial parity odd|even|none" and
926 "show serial parity". These allows to set or show parity for the
929 * The "info source" command now displays the producer string if it was
930 present in the debug info. This typically includes the compiler version
931 and may include things like its command line arguments.
933 * The "info dll", an alias of the "info sharedlibrary" command,
934 is now available on all platforms.
936 * Directory names supplied to the "set sysroot" commands may be
937 prefixed with "target:" to tell GDB to access shared libraries from
938 the target system, be it local or remote. This replaces the prefix
939 "remote:". The default sysroot has been changed from "" to
940 "target:". "remote:" is automatically converted to "target:" for
941 backward compatibility.
943 * The system root specified by "set sysroot" will be prepended to the
944 filename of the main executable (if reported to GDB as absolute by
945 the operating system) when starting processes remotely, and when
946 attaching to already-running local or remote processes.
948 * GDB now supports automatic location and retrieval of executable
949 files from remote targets. Remote debugging can now be initiated
950 using only a "target remote" or "target extended-remote" command
951 (no "set sysroot" or "file" commands are required). See "New remote
954 * The "dump" command now supports verilog hex format.
956 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
958 * On GNU/Linux, GDB and gdbserver are now able to access executable
959 and shared library files without a "set sysroot" command when
960 attaching to processes running in different mount namespaces from
961 the debugger. This makes it possible to attach to processes in
962 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
963 See "New remote packets" below.
965 * The "tui reg" command now provides completion for all of the
966 available register groups, including target specific groups.
968 * The HISTSIZE environment variable is no longer read when determining
969 the size of GDB's command history. GDB now instead reads the dedicated
970 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
971 disables truncation of command history. Non-numeric values of GDBHISTSIZE
976 ** Memory ports can now be unbuffered.
980 ** gdb.Objfile objects have a new attribute "username",
981 which is the name of the objfile as specified by the user,
982 without, for example, resolving symlinks.
983 ** You can now write frame unwinders in Python.
984 ** gdb.Type objects have a new method "optimized_out",
985 returning optimized out gdb.Value instance of this type.
986 ** gdb.Value objects have new methods "reference_value" and
987 "const_value" which return a reference to the value and a
988 "const" version of the value respectively.
992 maint print symbol-cache
993 Print the contents of the symbol cache.
995 maint print symbol-cache-statistics
996 Print statistics of symbol cache usage.
998 maint flush-symbol-cache
999 Flush the contents of the symbol cache.
1003 Start branch trace recording using Branch Trace Store (BTS) format.
1006 Evaluate expression by using the compiler and print result.
1010 Explicit commands for enabling and disabling tui mode.
1013 set mpx bound on i386 and amd64
1014 Support for bound table investigation on Intel MPX enabled applications.
1018 Start branch trace recording using Intel Processor Trace format.
1021 Print information about branch tracing internals.
1023 maint btrace packet-history
1024 Print the raw branch tracing data.
1026 maint btrace clear-packet-history
1027 Discard the stored raw branch tracing data.
1030 Discard all branch tracing data. It will be fetched and processed
1031 anew by the next "record" command.
1036 Renamed from "set debug dwarf2-die".
1037 show debug dwarf-die
1038 Renamed from "show debug dwarf2-die".
1040 set debug dwarf-read
1041 Renamed from "set debug dwarf2-read".
1042 show debug dwarf-read
1043 Renamed from "show debug dwarf2-read".
1045 maint set dwarf always-disassemble
1046 Renamed from "maint set dwarf2 always-disassemble".
1047 maint show dwarf always-disassemble
1048 Renamed from "maint show dwarf2 always-disassemble".
1050 maint set dwarf max-cache-age
1051 Renamed from "maint set dwarf2 max-cache-age".
1052 maint show dwarf max-cache-age
1053 Renamed from "maint show dwarf2 max-cache-age".
1055 set debug dwarf-line
1056 show debug dwarf-line
1057 Control display of debugging info regarding DWARF line processing.
1060 show max-completions
1061 Set the maximum number of candidates to be considered during
1062 completion. The default value is 200. This limit allows GDB
1063 to avoid generating large completion lists, the computation of
1064 which can cause the debugger to become temporarily unresponsive.
1066 set history remove-duplicates
1067 show history remove-duplicates
1068 Control the removal of duplicate history entries.
1070 maint set symbol-cache-size
1071 maint show symbol-cache-size
1072 Control the size of the symbol cache.
1074 set|show record btrace bts buffer-size
1075 Set and show the size of the ring buffer used for branch tracing in
1077 The obtained size may differ from the requested size. Use "info
1078 record" to see the obtained buffer size.
1080 set debug linux-namespaces
1081 show debug linux-namespaces
1082 Control display of debugging info regarding Linux namespaces.
1084 set|show record btrace pt buffer-size
1085 Set and show the size of the ring buffer used for branch tracing in
1086 Intel Processor Trace format.
1087 The obtained size may differ from the requested size. Use "info
1088 record" to see the obtained buffer size.
1090 maint set|show btrace pt skip-pad
1091 Set and show whether PAD packets are skipped when computing the
1094 * The command 'thread apply all' can now support new option '-ascending'
1095 to call its specified command for all threads in ascending order.
1097 * Python/Guile scripting
1099 ** GDB now supports auto-loading of Python/Guile scripts contained in the
1100 special section named `.debug_gdb_scripts'.
1102 * New remote packets
1104 qXfer:btrace-conf:read
1105 Return the branch trace configuration for the current thread.
1107 Qbtrace-conf:bts:size
1108 Set the requested ring buffer size for branch tracing in BTS format.
1111 Enable Intel Procesor Trace-based branch tracing for the current
1112 process. The remote stub reports support for this packet to GDB's
1115 Qbtrace-conf:pt:size
1116 Set the requested ring buffer size for branch tracing in Intel Processor
1120 Indicates a memory breakpoint instruction was executed, irrespective
1121 of whether it was GDB that planted the breakpoint or the breakpoint
1122 is hardcoded in the program. This is required for correct non-stop
1126 Indicates the target stopped for a hardware breakpoint. This is
1127 required for correct non-stop mode operation.
1130 Return information about files on the remote system.
1132 qXfer:exec-file:read
1133 Return the full absolute name of the file that was executed to
1134 create a process running on the remote system.
1137 Select the filesystem on which vFile: operations with filename
1138 arguments will operate. This is required for GDB to be able to
1139 access files on remote targets where the remote stub does not
1140 share a common filesystem with the inferior(s).
1143 Indicates that a fork system call was executed.
1146 Indicates that a vfork system call was executed.
1148 vforkdone stop reason
1149 Indicates that a vfork child of the specified process has executed
1150 an exec or exit, allowing the vfork parent to resume execution.
1152 fork-events and vfork-events features in qSupported
1153 The qSupported packet allows GDB to request support for fork and
1154 vfork events using new 'gdbfeatures' fork-events and vfork-events,
1155 and the qSupported response can contain the corresponding
1156 'stubfeatures'. Set and show commands can be used to display
1157 whether these features are enabled.
1159 * Extended-remote fork events
1161 ** GDB now has support for fork events on extended-remote Linux
1162 targets. For targets with Linux kernels 2.5.60 and later, this
1163 enables follow-fork-mode and detach-on-fork for both fork and
1164 vfork, as well as fork and vfork catchpoints.
1166 * The info record command now shows the recording format and the
1167 branch tracing configuration for the current thread when using
1168 the btrace record target.
1169 For the BTS format, it shows the ring buffer size.
1171 * GDB now has support for DTrace USDT (Userland Static Defined
1172 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
1174 * GDB now supports access to vector registers on S/390 GNU/Linux
1177 * Removed command line options
1179 -xdb HP-UX XDB compatibility mode.
1181 * Removed targets and native configurations
1183 HP/PA running HP-UX hppa*-*-hpux*
1184 Itanium running HP-UX ia64-*-hpux*
1186 * New configure options
1189 This configure option allows the user to build GDB with support for
1190 Intel Processor Trace (default: auto). This requires libipt.
1192 --with-libipt-prefix=PATH
1193 Specify the path to the version of libipt that GDB should use.
1194 $PATH/include should contain the intel-pt.h header and
1195 $PATH/lib should contain the libipt.so library.
1197 *** Changes in GDB 7.9.1
1201 ** Xmethods can now specify a result type.
1203 *** Changes in GDB 7.9
1205 * GDB now supports hardware watchpoints on x86 GNU Hurd.
1209 ** You can now access frame registers from Python scripts.
1210 ** New attribute 'producer' for gdb.Symtab objects.
1211 ** gdb.Objfile objects have a new attribute "progspace",
1212 which is the gdb.Progspace object of the containing program space.
1213 ** gdb.Objfile objects have a new attribute "owner".
1214 ** gdb.Objfile objects have a new attribute "build_id",
1215 which is the build ID generated when the file was built.
1216 ** gdb.Objfile objects have a new method "add_separate_debug_file".
1217 ** A new event "gdb.clear_objfiles" has been added, triggered when
1218 selecting a new file to debug.
1219 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
1220 ** New function gdb.lookup_objfile.
1222 New events which are triggered when GDB modifies the state of the
1225 ** gdb.events.inferior_call_pre: Function call is about to be made.
1226 ** gdb.events.inferior_call_post: Function call has just been made.
1227 ** gdb.events.memory_changed: A memory location has been altered.
1228 ** gdb.events.register_changed: A register has been altered.
1230 * New Python-based convenience functions:
1232 ** $_caller_is(name [, number_of_frames])
1233 ** $_caller_matches(regexp [, number_of_frames])
1234 ** $_any_caller_is(name [, number_of_frames])
1235 ** $_any_caller_matches(regexp [, number_of_frames])
1237 * GDB now supports the compilation and injection of source code into
1238 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
1239 to compile the source code to object code, and if successful, inject
1240 and execute that code within the current context of the inferior.
1241 Currently the C language is supported. The commands used to
1242 interface with this new feature are:
1244 compile code [-raw|-r] [--] [source code]
1245 compile file [-raw|-r] filename
1249 demangle [-l language] [--] name
1250 Demangle "name" in the specified language, or the current language
1251 if elided. This command is renamed from the "maint demangle" command.
1252 The latter is kept as a no-op to avoid "maint demangle" being interpreted
1253 as "maint demangler-warning".
1255 queue-signal signal-name-or-number
1256 Queue a signal to be delivered to the thread when it is resumed.
1258 add-auto-load-scripts-directory directory
1259 Add entries to the list of directories from which to load auto-loaded
1262 maint print user-registers
1263 List all currently available "user" registers.
1265 compile code [-r|-raw] [--] [source code]
1266 Compile, inject, and execute in the inferior the executable object
1267 code produced by compiling the provided source code.
1269 compile file [-r|-raw] filename
1270 Compile and inject into the inferior the executable object code
1271 produced by compiling the source code stored in the filename
1274 * On resume, GDB now always passes the signal the program had stopped
1275 for to the thread the signal was sent to, even if the user changed
1276 threads before resuming. Previously GDB would often (but not
1277 always) deliver the signal to the thread that happens to be current
1280 * Conversely, the "signal" command now consistently delivers the
1281 requested signal to the current thread. GDB now asks for
1282 confirmation if the program had stopped for a signal and the user
1283 switched threads meanwhile.
1285 * "breakpoint always-inserted" modes "off" and "auto" merged.
1287 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
1288 won't remove breakpoints from the target until all threads stop,
1289 even in non-stop mode. The "auto" mode has been removed, and "off"
1290 is now the default mode.
1294 set debug symbol-lookup
1295 show debug symbol-lookup
1296 Control display of debugging info regarding symbol lookup.
1300 ** The -list-thread-groups command outputs an exit-code field for
1301 inferiors that have exited.
1305 MIPS SDE mips*-sde*-elf*
1309 Support for these obsolete configurations has been removed.
1311 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
1312 SGI Irix-5.x mips-*-irix5*
1313 SGI Irix-6.x mips-*-irix6*
1314 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
1315 VAX running Ultrix vax-*-ultrix*
1317 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1318 and "assf"), have been removed. Use the "sharedlibrary" command, or
1319 its alias "share", instead.
1321 *** Changes in GDB 7.8
1323 * New command line options
1326 This is an alias for the --data-directory option.
1328 * GDB supports printing and modifying of variable length automatic arrays
1329 as specified in ISO C99.
1331 * The ARM simulator now supports instruction level tracing
1332 with or without disassembly.
1336 GDB now has support for scripting using Guile. Whether this is
1337 available is determined at configure time.
1338 Guile version 2.0 or greater is required.
1339 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
1341 * New commands (for set/show, see "New options" below)
1345 Invoke CODE by passing it to the Guile interpreter.
1349 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
1351 info auto-load guile-scripts [regexp]
1352 Print the list of automatically loaded Guile scripts.
1354 * The source command is now capable of sourcing Guile scripts.
1355 This feature is dependent on the debugger being built with Guile support.
1359 set print symbol-loading (off|brief|full)
1360 show print symbol-loading
1361 Control whether to print informational messages when loading symbol
1362 information for a file. The default is "full", but when debugging
1363 programs with large numbers of shared libraries the amount of output
1364 becomes less useful.
1366 set guile print-stack (none|message|full)
1367 show guile print-stack
1368 Show a stack trace when an error is encountered in a Guile script.
1370 set auto-load guile-scripts (on|off)
1371 show auto-load guile-scripts
1372 Control auto-loading of Guile script files.
1374 maint ada set ignore-descriptive-types (on|off)
1375 maint ada show ignore-descriptive-types
1376 Control whether the debugger should ignore descriptive types in Ada
1377 programs. The default is not to ignore the descriptive types. See
1378 the user manual for more details on descriptive types and the intended
1379 usage of this option.
1381 set auto-connect-native-target
1383 Control whether GDB is allowed to automatically connect to the
1384 native target for the run, attach, etc. commands when not connected
1385 to any target yet. See also "target native" below.
1387 set record btrace replay-memory-access (read-only|read-write)
1388 show record btrace replay-memory-access
1389 Control what memory accesses are allowed during replay.
1391 maint set target-async (on|off)
1392 maint show target-async
1393 This controls whether GDB targets operate in synchronous or
1394 asynchronous mode. Normally the default is asynchronous, if it is
1395 available; but this can be changed to more easily debug problems
1396 occurring only in synchronous mode.
1398 set mi-async (on|off)
1400 Control whether MI asynchronous mode is preferred. This supersedes
1401 "set target-async" of previous GDB versions.
1403 * "set target-async" is deprecated as a CLI option and is now an alias
1404 for "set mi-async" (only puts MI into async mode).
1406 * Background execution commands (e.g., "c&", "s&", etc.) are now
1407 possible ``out of the box'' if the target supports them. Previously
1408 the user would need to explicitly enable the possibility with the
1409 "set target-async on" command.
1411 * New features in the GDB remote stub, GDBserver
1413 ** New option --debug-format=option1[,option2,...] allows one to add
1414 additional text to each output. At present only timestamps
1415 are supported: --debug-format=timestamps.
1416 Timestamps can also be turned on with the
1417 "monitor set debug-format timestamps" command from GDB.
1419 * The 'record instruction-history' command now starts counting instructions
1420 at one. This also affects the instruction ranges reported by the
1421 'record function-call-history' command when given the /i modifier.
1423 * The command 'record function-call-history' supports a new modifier '/c' to
1424 indent the function names based on their call stack depth.
1425 The fields for the '/i' and '/l' modifier have been reordered.
1426 The source line range is now prefixed with 'at'.
1427 The instruction range is now prefixed with 'inst'.
1428 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1429 "record instruction-history" and "list" commands.
1431 * The ranges given as arguments to the 'record function-call-history' and
1432 'record instruction-history' commands are now inclusive.
1434 * The btrace record target now supports the 'record goto' command.
1435 For locations inside the execution trace, the back trace is computed
1436 based on the information stored in the execution trace.
1438 * The btrace record target supports limited reverse execution and replay.
1439 The target does not record data and therefore does not allow reading
1440 memory or registers.
1442 * The "catch syscall" command now works on s390*-linux* targets.
1444 * The "compare-sections" command is no longer specific to target
1445 remote. It now works with all targets.
1447 * All native targets are now consistently called "native".
1448 Consequently, the "target child", "target GNU", "target djgpp",
1449 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1450 commands have been replaced with "target native". The QNX/NTO port
1451 leaves the "procfs" target in place and adds a "native" target for
1452 consistency with other ports. The impact on users should be minimal
1453 as these commands previously either throwed an error, or were
1454 no-ops. The target's name is visible in the output of the following
1455 commands: "help target", "info target", "info files", "maint print
1458 * The "target native" command now connects to the native target. This
1459 can be used to launch native programs even when "set
1460 auto-connect-native-target" is set to off.
1462 * GDB now supports access to Intel MPX registers on GNU/Linux.
1464 * Support for Intel AVX-512 registers on GNU/Linux.
1465 Support displaying and modifying Intel AVX-512 registers
1466 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1468 * New remote packets
1470 qXfer:btrace:read's annex
1471 The qXfer:btrace:read packet supports a new annex 'delta' to read
1472 branch trace incrementally.
1476 ** Valid Python operations on gdb.Value objects representing
1477 structs/classes invoke the corresponding overloaded operators if
1479 ** New `Xmethods' feature in the Python API. Xmethods are
1480 additional methods or replacements for existing methods of a C++
1481 class. This feature is useful for those cases where a method
1482 defined in C++ source code could be inlined or optimized out by
1483 the compiler, making it unavailable to GDB.
1486 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1488 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1489 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1490 its alias "share", instead.
1492 * The commands "set remotebaud" and "show remotebaud" are no longer
1493 supported. Use "set serial baud" and "show serial baud" (respectively)
1498 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1499 target-async". The latter is left as a deprecated alias of the
1500 former for backward compatibility. If the target supports it,
1501 CLI background execution commands are now always possible by
1502 default, independently of whether the frontend stated a
1503 preference for asynchronous execution with "-gdb-set mi-async".
1504 Previously "-gdb-set target-async off" affected both MI execution
1505 commands and CLI execution commands.
1507 *** Changes in GDB 7.7
1509 * Improved support for process record-replay and reverse debugging on
1510 arm*-linux* targets. Support for thumb32 and syscall instruction
1511 recording has been added.
1513 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1515 * GDB now supports Fission DWP file format version 2.
1516 http://gcc.gnu.org/wiki/DebugFission
1518 * New convenience function "$_isvoid", to check whether an expression
1519 is void. A void expression is an expression where the type of the
1520 result is "void". For example, some convenience variables may be
1521 "void" when evaluated (e.g., "$_exitcode" before the execution of
1522 the program being debugged; or an undefined convenience variable).
1523 Another example, when calling a function whose return type is
1526 * The "maintenance print objfiles" command now takes an optional regexp.
1528 * The "catch syscall" command now works on arm*-linux* targets.
1530 * GDB now consistently shows "<not saved>" when printing values of
1531 registers the debug info indicates have not been saved in the frame
1532 and there's nowhere to retrieve them from
1533 (callee-saved/call-clobbered registers):
1538 (gdb) info registers rax
1541 Before, the former would print "<optimized out>", and the latter
1542 "*value not available*".
1544 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1549 ** Frame filters and frame decorators have been added.
1550 ** Temporary breakpoints are now supported.
1551 ** Line tables representation has been added.
1552 ** New attribute 'parent_type' for gdb.Field objects.
1553 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1554 ** New attribute 'name' for gdb.Type objects.
1558 Nios II ELF nios2*-*-elf
1559 Nios II GNU/Linux nios2*-*-linux
1560 Texas Instruments MSP430 msp430*-*-elf
1562 * Removed native configurations
1564 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1565 been removed. ELF variants of these configurations are kept supported.
1567 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1568 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1569 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1570 i[34567]86-*-openbsd3.[0-3]
1571 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1572 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1573 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1577 Like "catch throw", but catches a re-thrown exception.
1578 maint check-psymtabs
1579 Renamed from old "maint check-symtabs".
1581 Perform consistency checks on symtabs.
1582 maint expand-symtabs
1583 Expand symtabs matching an optional regexp.
1586 Display the details of GDB configure-time options.
1588 maint set|show per-command
1589 maint set|show per-command space
1590 maint set|show per-command time
1591 maint set|show per-command symtab
1592 Enable display of per-command gdb resource usage.
1594 remove-symbol-file FILENAME
1595 remove-symbol-file -a ADDRESS
1596 Remove a symbol file added via add-symbol-file. The file to remove
1597 can be identified by its filename or by an address that lies within
1598 the boundaries of this symbol file in memory.
1601 info exceptions REGEXP
1602 Display the list of Ada exceptions defined in the program being
1603 debugged. If provided, only the exceptions whose names match REGEXP
1608 set debug symfile off|on
1610 Control display of debugging info regarding reading symbol files and
1611 symbol tables within those files
1613 set print raw frame-arguments
1614 show print raw frame-arguments
1615 Set/show whether to print frame arguments in raw mode,
1616 disregarding any defined pretty-printers.
1618 set remote trace-status-packet
1619 show remote trace-status-packet
1620 Set/show the use of remote protocol qTStatus packet.
1624 Control display of debugging messages related to Nios II targets.
1628 Control whether target-assisted range stepping is enabled.
1630 set startup-with-shell
1631 show startup-with-shell
1632 Specifies whether Unix child processes are started via a shell or
1637 Use the target memory cache for accesses to the code segment. This
1638 improves performance of remote debugging (particularly disassembly).
1640 * You can now use a literal value 'unlimited' for options that
1641 interpret 0 or -1 as meaning "unlimited". E.g., "set
1642 trace-buffer-size unlimited" is now an alias for "set
1643 trace-buffer-size -1" and "set height unlimited" is now an alias for
1646 * The "set debug symtab-create" debugging option of GDB has been changed to
1647 accept a verbosity level. 0 means "off", 1 provides basic debugging
1648 output, and values of 2 or greater provides more verbose output.
1650 * New command-line options
1652 Display the details of GDB configure-time options.
1654 * The command 'tsave' can now support new option '-ctf' to save trace
1655 buffer in Common Trace Format.
1657 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1660 * GDB now implements the the C++ 'typeid' operator.
1662 * The new convenience variable $_exception holds the exception being
1663 thrown or caught at an exception-related catchpoint.
1665 * The exception-related catchpoints, like "catch throw", now accept a
1666 regular expression which can be used to filter exceptions by type.
1668 * The new convenience variable $_exitsignal is automatically set to
1669 the terminating signal number when the program being debugged dies
1670 due to an uncaught signal.
1674 ** All MI commands now accept an optional "--language" option.
1675 Support for this feature can be verified by using the "-list-features"
1676 command, which should contain "language-option".
1678 ** The new command -info-gdb-mi-command allows the user to determine
1679 whether a GDB/MI command is supported or not.
1681 ** The "^error" result record returned when trying to execute an undefined
1682 GDB/MI command now provides a variable named "code" whose content is the
1683 "undefined-command" error code. Support for this feature can be verified
1684 by using the "-list-features" command, which should contain
1685 "undefined-command-error-code".
1687 ** The -trace-save MI command can optionally save trace buffer in Common
1690 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1692 ** The command -data-list-register-values now accepts an optional
1693 "--skip-unavailable" option. When used, only the available registers
1696 ** The new command -trace-frame-collected dumps collected variables,
1697 computed expressions, tvars, memory and registers in a traceframe.
1699 ** The commands -stack-list-locals, -stack-list-arguments and
1700 -stack-list-variables now accept an option "--skip-unavailable".
1701 When used, only the available locals or arguments are displayed.
1703 ** The -exec-run command now accepts an optional "--start" option.
1704 When used, the command follows the same semantics as the "start"
1705 command, stopping the program's execution at the start of its
1706 main subprogram. Support for this feature can be verified using
1707 the "-list-features" command, which should contain
1708 "exec-run-start-option".
1710 ** The new commands -catch-assert and -catch-exceptions insert
1711 catchpoints stopping the program when Ada exceptions are raised.
1713 ** The new command -info-ada-exceptions provides the equivalent of
1714 the new "info exceptions" command.
1716 * New system-wide configuration scripts
1717 A GDB installation now provides scripts suitable for use as system-wide
1718 configuration scripts for the following systems:
1722 * GDB now supports target-assigned range stepping with remote targets.
1723 This improves the performance of stepping source lines by reducing
1724 the number of control packets from/to GDB. See "New remote packets"
1727 * GDB now understands the element 'tvar' in the XML traceframe info.
1728 It has the id of the collected trace state variables.
1730 * On S/390 targets that provide the transactional-execution feature,
1731 the program interruption transaction diagnostic block (TDB) is now
1732 represented as a number of additional "registers" in GDB.
1734 * New remote packets
1738 The vCont packet supports a new 'r' action, that tells the remote
1739 stub to step through an address range itself, without GDB
1740 involvemement at each single-step.
1742 qXfer:libraries-svr4:read's annex
1743 The previously unused annex of the qXfer:libraries-svr4:read packet
1744 is now used to support passing an argument list. The remote stub
1745 reports support for this argument list to GDB's qSupported query.
1746 The defined arguments are "start" and "prev", used to reduce work
1747 necessary for library list updating, resulting in significant
1750 * New features in the GDB remote stub, GDBserver
1752 ** GDBserver now supports target-assisted range stepping. Currently
1753 enabled on x86/x86_64 GNU/Linux targets.
1755 ** GDBserver now adds element 'tvar' in the XML in the reply to
1756 'qXfer:traceframe-info:read'. It has the id of the collected
1757 trace state variables.
1759 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1762 * New 'z' formatter for printing and examining memory, this displays the
1763 value as hexadecimal zero padded on the left to the size of the type.
1765 * GDB can now use Windows x64 unwinding data.
1767 * The "set remotebaud" command has been replaced by "set serial baud".
1768 Similarly, "show remotebaud" has been replaced by "show serial baud".
1769 The "set remotebaud" and "show remotebaud" commands are still available
1770 to provide backward compatibility with older versions of GDB.
1772 *** Changes in GDB 7.6
1774 * Target record has been renamed to record-full.
1775 Record/replay is now enabled with the "record full" command.
1776 This also affects settings that are associated with full record/replay
1777 that have been moved from "set/show record" to "set/show record full":
1779 set|show record full insn-number-max
1780 set|show record full stop-at-limit
1781 set|show record full memory-query
1783 * A new record target "record-btrace" has been added. The new target
1784 uses hardware support to record the control-flow of a process. It
1785 does not support replaying the execution, but it implements the
1786 below new commands for investigating the recorded execution log.
1787 This new recording method can be enabled using:
1791 The "record-btrace" target is only available on Intel Atom processors
1792 and requires a Linux kernel 2.6.32 or later.
1794 * Two new commands have been added for record/replay to give information
1795 about the recorded execution without having to replay the execution.
1796 The commands are only supported by "record btrace".
1798 record instruction-history prints the execution history at
1799 instruction granularity
1801 record function-call-history prints the execution history at
1802 function granularity
1804 * New native configurations
1806 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1807 FreeBSD/powerpc powerpc*-*-freebsd
1808 x86_64/Cygwin x86_64-*-cygwin*
1809 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1813 ARM AArch64 aarch64*-*-elf
1814 ARM AArch64 GNU/Linux aarch64*-*-linux
1815 Lynx 178 PowerPC powerpc-*-lynx*178
1816 x86_64/Cygwin x86_64-*-cygwin*
1817 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1819 * If the configured location of system.gdbinit file (as given by the
1820 --with-system-gdbinit option at configure time) is in the
1821 data-directory (as specified by --with-gdb-datadir at configure
1822 time) or in one of its subdirectories, then GDB will look for the
1823 system-wide init file in the directory specified by the
1824 --data-directory command-line option.
1826 * New command line options:
1828 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1829 other initialization files, unlike -nx which disables all of them.
1831 * Removed command line options
1833 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1836 * The 'ptype' and 'whatis' commands now accept an argument to control
1839 * 'info proc' now works on some core files.
1843 ** Vectors can be created with gdb.Type.vector.
1845 ** Python's atexit.register now works in GDB.
1847 ** Types can be pretty-printed via a Python API.
1849 ** Python 3 is now supported (in addition to Python 2.4 or later)
1851 ** New class gdb.Architecture exposes GDB's internal representation
1852 of architecture in the Python API.
1854 ** New method Frame.architecture returns the gdb.Architecture object
1855 corresponding to the frame's architecture.
1857 * New Python-based convenience functions:
1859 ** $_memeq(buf1, buf2, length)
1860 ** $_streq(str1, str2)
1862 ** $_regex(str, regex)
1864 * The 'cd' command now defaults to using '~' (the home directory) if not
1867 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1868 default for GCC since November 2000.
1870 * The command 'forward-search' can now be abbreviated as 'fo'.
1872 * The command 'info tracepoints' can now display 'installed on target'
1873 or 'not installed on target' for each non-pending location of tracepoint.
1875 * New configure options
1877 --enable-libmcheck/--disable-libmcheck
1878 By default, development versions are built with -lmcheck on hosts
1879 that support it, in order to help track memory corruption issues.
1880 Release versions, on the other hand, are built without -lmcheck
1881 by default. The --enable-libmcheck/--disable-libmcheck configure
1882 options allow the user to override that default.
1883 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1884 This configure option allows the user to build GDB with
1885 libbabeltrace using which GDB can read Common Trace Format data.
1887 * New commands (for set/show, see "New options" below)
1890 Catch signals. This is similar to "handle", but allows commands and
1891 conditions to be attached.
1894 List the BFDs known to GDB.
1896 python-interactive [command]
1898 Start a Python interactive prompt, or evaluate the optional command
1899 and print the result of expressions.
1902 "py" is a new alias for "python".
1904 enable type-printer [name]...
1905 disable type-printer [name]...
1906 Enable or disable type printers.
1910 ** For the Renesas Super-H architecture, the "regs" command has been removed
1911 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1916 set print type methods (on|off)
1917 show print type methods
1918 Control whether method declarations are displayed by "ptype".
1919 The default is to show them.
1921 set print type typedefs (on|off)
1922 show print type typedefs
1923 Control whether typedef definitions are displayed by "ptype".
1924 The default is to show them.
1926 set filename-display basename|relative|absolute
1927 show filename-display
1928 Control the way in which filenames is displayed.
1929 The default is "relative", which preserves previous behavior.
1931 set trace-buffer-size
1932 show trace-buffer-size
1933 Request target to change the size of trace buffer.
1935 set remote trace-buffer-size-packet auto|on|off
1936 show remote trace-buffer-size-packet
1937 Control the use of the remote protocol `QTBuffer:size' packet.
1941 Control display of debugging messages related to ARM AArch64.
1944 set debug coff-pe-read
1945 show debug coff-pe-read
1946 Control display of debugging messages related to reading of COFF/PE
1951 Control display of debugging messages related to Mach-O symbols
1954 set debug notification
1955 show debug notification
1956 Control display of debugging info for async remote notification.
1960 ** Command parameter changes are now notified using new async record
1961 "=cmd-param-changed".
1962 ** Trace frame changes caused by command "tfind" are now notified using
1963 new async record "=traceframe-changed".
1964 ** The creation, deletion and modification of trace state variables
1965 are now notified using new async records "=tsv-created",
1966 "=tsv-deleted" and "=tsv-modified".
1967 ** The start and stop of process record are now notified using new
1968 async record "=record-started" and "=record-stopped".
1969 ** Memory changes are now notified using new async record
1971 ** The data-disassemble command response will include a "fullname" field
1972 containing the absolute file name when source has been requested.
1973 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1974 command, to allow pattern filling of memory areas.
1975 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1976 library load/unload events.
1977 ** The response to breakpoint commands and breakpoint async records
1978 includes an "installed" field containing a boolean state about each
1979 non-pending tracepoint location is whether installed on target or not.
1980 ** Output of the "-trace-status" command includes a "trace-file" field
1981 containing the name of the trace file being examined. This field is
1982 optional, and only present when examining a trace file.
1983 ** The "fullname" field is now always present along with the "file" field,
1984 even if the file cannot be found by GDB.
1986 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1987 You must have the LZMA library available when configuring GDB for this
1988 feature to be enabled. For more information, see:
1989 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1991 * New remote packets
1994 Set the size of trace buffer. The remote stub reports support for this
1995 packet to gdb's qSupported query.
1998 Enable Branch Trace Store (BTS)-based branch tracing for the current
1999 thread. The remote stub reports support for this packet to gdb's
2003 Disable branch tracing for the current thread. The remote stub reports
2004 support for this packet to gdb's qSupported query.
2007 Read the traced branches for the current thread. The remote stub
2008 reports support for this packet to gdb's qSupported query.
2010 *** Changes in GDB 7.5
2012 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
2013 for more x32 ABI info.
2015 * GDB now supports access to MIPS DSP registers on Linux targets.
2017 * GDB now supports debugging microMIPS binaries.
2019 * The "info os" command on GNU/Linux can now display information on
2020 several new classes of objects managed by the operating system:
2021 "info os procgroups" lists process groups
2022 "info os files" lists file descriptors
2023 "info os sockets" lists internet-domain sockets
2024 "info os shm" lists shared-memory regions
2025 "info os semaphores" lists semaphores
2026 "info os msg" lists message queues
2027 "info os modules" lists loaded kernel modules
2029 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
2030 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
2031 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
2032 options and inspect the probe arguments using the new $_probe_arg family
2033 of convenience variables. You can obtain more information about SystemTap
2034 in <http://sourceware.org/systemtap/>.
2036 * GDB now supports reversible debugging on ARM, it allows you to
2037 debug basic ARM and THUMB instructions, and provides
2038 record/replay support.
2040 * The option "symbol-reloading" has been deleted as it is no longer used.
2044 ** GDB commands implemented in Python can now be put in command class
2047 ** The "maint set python print-stack on|off" is now deleted.
2049 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
2050 apply "flag enum"-style pretty-printing to any enum.
2052 ** gdb.lookup_symbol can now work when there is no current frame.
2054 ** gdb.Symbol now has a 'line' attribute, holding the line number in
2055 the source at which the symbol was defined.
2057 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
2058 method 'value'. The former indicates whether the symbol needs a
2059 frame in order to compute its value, and the latter computes the
2062 ** A new method 'referenced_value' on gdb.Value objects which can
2063 dereference pointer as well as C++ reference values.
2065 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
2066 which return the global and static blocks (as gdb.Block objects),
2067 of the underlying symbol table, respectively.
2069 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
2070 object associated with a PC value.
2072 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
2073 of the address range occupied by code for the current source line.
2075 * Go language support.
2076 GDB now supports debugging programs written in the Go programming
2079 * GDBserver now supports stdio connections.
2080 E.g. (gdb) target remote | ssh myhost gdbserver - hello
2082 * The binary "gdbtui" can no longer be built or installed.
2083 Use "gdb -tui" instead.
2085 * GDB will now print "flag" enums specially. A flag enum is one where
2086 all the enumerator values have no bits in common when pairwise
2087 "and"ed. When printing a value whose type is a flag enum, GDB will
2088 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
2089 (gdb) print (enum E) 3
2092 * The filename part of a linespec will now match trailing components
2093 of a source file name. For example, "break gcc/expr.c:1000" will
2094 now set a breakpoint in build/gcc/expr.c, but not
2095 build/libcpp/expr.c.
2097 * The "info proc" and "generate-core-file" commands will now also
2098 work on remote targets connected to GDBserver on Linux.
2100 * The command "info catch" has been removed. It has been disabled
2101 since December 2007.
2103 * The "catch exception" and "catch assert" commands now accept
2104 a condition at the end of the command, much like the "break"
2105 command does. For instance:
2107 (gdb) catch exception Constraint_Error if Barrier = True
2109 Previously, it was possible to add a condition to such catchpoints,
2110 but it had to be done as a second step, after the catchpoint had been
2111 created, using the "condition" command.
2113 * The "info static-tracepoint-marker" command will now also work on
2114 native Linux targets with in-process agent.
2116 * GDB can now set breakpoints on inlined functions.
2118 * The .gdb_index section has been updated to include symbols for
2119 inlined functions. GDB will ignore older .gdb_index sections by
2120 default, which could cause symbol files to be loaded more slowly
2121 until their .gdb_index sections can be recreated. The new command
2122 "set use-deprecated-index-sections on" will cause GDB to use any older
2123 .gdb_index sections it finds. This will restore performance, but the
2124 ability to set breakpoints on inlined functions will be lost in symbol
2125 files with older .gdb_index sections.
2127 The .gdb_index section has also been updated to record more information
2128 about each symbol. This speeds up the "info variables", "info functions"
2129 and "info types" commands when used with programs having the .gdb_index
2130 section, as well as speeding up debugging with shared libraries using
2131 the .gdb_index section.
2133 * Ada support for GDB/MI Variable Objects has been added.
2135 * GDB can now support 'breakpoint always-inserted mode' in 'record'
2140 ** New command -info-os is the MI equivalent of "info os".
2142 ** Output logs ("set logging" and related) now include MI output.
2146 ** "set use-deprecated-index-sections on|off"
2147 "show use-deprecated-index-sections on|off"
2148 Controls the use of deprecated .gdb_index sections.
2150 ** "catch load" and "catch unload" can be used to stop when a shared
2151 library is loaded or unloaded, respectively.
2153 ** "enable count" can be used to auto-disable a breakpoint after
2156 ** "info vtbl" can be used to show the virtual method tables for
2157 C++ and Java objects.
2159 ** "explore" and its sub commands "explore value" and "explore type"
2160 can be used to recursively explore values and types of
2161 expressions. These commands are available only if GDB is
2162 configured with '--with-python'.
2164 ** "info auto-load" shows status of all kinds of auto-loaded files,
2165 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
2166 sequences of commands files, "info auto-load python-scripts"
2167 shows status of auto-loading Python script files,
2168 "info auto-load local-gdbinit" shows status of loading init file
2169 (.gdbinit) from current directory and "info auto-load libthread-db" shows
2170 status of inferior specific thread debugging shared library loading.
2172 ** "info auto-load-scripts", "set auto-load-scripts on|off"
2173 and "show auto-load-scripts" commands have been deprecated, use their
2174 "info auto-load python-scripts", "set auto-load python-scripts on|off"
2175 and "show auto-load python-scripts" counterparts instead.
2177 ** "dprintf location,format,args..." creates a dynamic printf, which
2178 is basically a breakpoint that does a printf and immediately
2179 resumes your program's execution, so it is like a printf that you
2180 can insert dynamically at runtime instead of at compiletime.
2182 ** "set print symbol"
2184 Controls whether GDB attempts to display the symbol, if any,
2185 corresponding to addresses it prints. This defaults to "on", but
2186 you can set it to "off" to restore GDB's previous behavior.
2188 * Deprecated commands
2190 ** For the Renesas Super-H architecture, the "regs" command has been
2191 deprecated, and "info all-registers" should be used instead.
2195 Renesas RL78 rl78-*-elf
2196 HP OpenVMS ia64 ia64-hp-openvms*
2198 * GDBserver supports evaluation of breakpoint conditions. When
2199 support is advertised by GDBserver, GDB may be told to send the
2200 breakpoint conditions in bytecode form to GDBserver. GDBserver
2201 will only report the breakpoint trigger to GDB when its condition
2206 set mips compression
2207 show mips compression
2208 Select the compressed ISA encoding used in functions that have no symbol
2209 information available. The encoding can be set to either of:
2212 and is updated automatically from ELF file flags if available.
2214 set breakpoint condition-evaluation
2215 show breakpoint condition-evaluation
2216 Control whether breakpoint conditions are evaluated by GDB ("host") or by
2217 GDBserver ("target"). Default option "auto" chooses the most efficient
2219 This option can improve debugger efficiency depending on the speed of the
2223 Disable auto-loading globally.
2226 Show auto-loading setting of all kinds of auto-loaded files.
2228 set auto-load gdb-scripts on|off
2229 show auto-load gdb-scripts
2230 Control auto-loading of GDB canned sequences of commands files.
2232 set auto-load python-scripts on|off
2233 show auto-load python-scripts
2234 Control auto-loading of Python script files.
2236 set auto-load local-gdbinit on|off
2237 show auto-load local-gdbinit
2238 Control loading of init file (.gdbinit) from current directory.
2240 set auto-load libthread-db on|off
2241 show auto-load libthread-db
2242 Control auto-loading of inferior specific thread debugging shared library.
2244 set auto-load scripts-directory <dir1>[:<dir2>...]
2245 show auto-load scripts-directory
2246 Set a list of directories from which to load auto-loaded scripts.
2247 Automatically loaded Python scripts and GDB scripts are located in one
2248 of the directories listed by this option.
2249 The delimiter (':' above) may differ according to the host platform.
2251 set auto-load safe-path <dir1>[:<dir2>...]
2252 show auto-load safe-path
2253 Set a list of directories from which it is safe to auto-load files.
2254 The delimiter (':' above) may differ according to the host platform.
2256 set debug auto-load on|off
2257 show debug auto-load
2258 Control display of debugging info for auto-loading the files above.
2260 set dprintf-style gdb|call|agent
2262 Control the way in which a dynamic printf is performed; "gdb"
2263 requests a GDB printf command, while "call" causes dprintf to call a
2264 function in the inferior. "agent" requests that the target agent
2265 (such as GDBserver) do the printing.
2267 set dprintf-function <expr>
2268 show dprintf-function
2269 set dprintf-channel <expr>
2270 show dprintf-channel
2271 Set the function and optional first argument to the call when using
2272 the "call" style of dynamic printf.
2274 set disconnected-dprintf on|off
2275 show disconnected-dprintf
2276 Control whether agent-style dynamic printfs continue to be in effect
2277 after GDB disconnects.
2279 * New configure options
2281 --with-auto-load-dir
2282 Configure default value for the 'set auto-load scripts-directory'
2283 setting above. It defaults to '$debugdir:$datadir/auto-load',
2284 $debugdir representing global debugging info directories (available
2285 via 'show debug-file-directory') and $datadir representing GDB's data
2286 directory (available via 'show data-directory').
2288 --with-auto-load-safe-path
2289 Configure default value for the 'set auto-load safe-path' setting
2290 above. It defaults to the --with-auto-load-dir setting.
2292 --without-auto-load-safe-path
2293 Set 'set auto-load safe-path' to '/', effectively disabling this
2296 * New remote packets
2298 z0/z1 conditional breakpoints extension
2300 The z0/z1 breakpoint insertion packets have been extended to carry
2301 a list of conditional expressions over to the remote stub depending on the
2302 condition evaluation mode. The use of this extension can be controlled
2303 via the "set remote conditional-breakpoints-packet" command.
2307 Specify the signals which the remote stub may pass to the debugged
2308 program without GDB involvement.
2310 * New command line options
2312 --init-command=FILE, -ix Like --command, -x but execute it
2313 before loading inferior.
2314 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
2315 execute it before loading inferior.
2317 *** Changes in GDB 7.4
2319 * GDB now handles ambiguous linespecs more consistently; the existing
2320 FILE:LINE support has been expanded to other types of linespecs. A
2321 breakpoint will now be set on all matching locations in all
2322 inferiors, and locations will be added or removed according to
2325 * GDB now allows you to skip uninteresting functions and files when
2326 stepping with the "skip function" and "skip file" commands.
2328 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
2329 and "show remote hardware-watchpoint-length-limit". These allows to
2330 set or show the maximum length limit (in bytes) of a remote
2331 target hardware watchpoint.
2333 This allows e.g. to use "unlimited" hardware watchpoints with the
2334 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
2335 watchpoints are slower than real hardware watchpoints but are
2336 significantly faster than gdb software watchpoints.
2340 ** The register_pretty_printer function in module gdb.printing now takes
2341 an optional `replace' argument. If True, the new printer replaces any
2344 ** The "maint set python print-stack on|off" command has been
2345 deprecated and will be deleted in GDB 7.5.
2346 A new command: "set python print-stack none|full|message" has
2347 replaced it. Additionally, the default for "print-stack" is
2348 now "message", which just prints the error message without
2351 ** A prompt substitution hook (prompt_hook) is now available to the
2354 ** A new Python module, gdb.prompt has been added to the GDB Python
2355 modules library. This module provides functionality for
2356 escape sequences in prompts (used by set/show
2357 extended-prompt). These escape sequences are replaced by their
2358 corresponding value.
2360 ** Python commands and convenience-functions located in
2361 'data-directory'/python/gdb/command and
2362 'data-directory'/python/gdb/function are now automatically loaded
2365 ** Blocks now provide four new attributes. global_block and
2366 static_block will return the global and static blocks
2367 respectively. is_static and is_global are boolean attributes
2368 that indicate if the block is one of those two types.
2370 ** Symbols now provide the "type" attribute, the type of the symbol.
2372 ** The "gdb.breakpoint" function has been deprecated in favor of
2375 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2376 of a function. This class is based on the "finish" command
2377 available in the CLI.
2379 ** Type objects for struct and union types now allow access to
2380 the fields using standard Python dictionary (mapping) methods.
2381 For example, "some_type['myfield']" now works, as does
2382 "some_type.items()".
2384 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2387 ** A new function, "deep_items" has been added to the gdb.types
2388 module in the GDB Python modules library. This function returns
2389 an iterator over the fields of a struct or union type. Unlike
2390 the standard Python "iteritems" method, it will recursively traverse
2391 any anonymous fields.
2395 ** "*stopped" events can report several new "reason"s, such as
2398 ** Breakpoint changes are now notified using new async records, like
2399 "=breakpoint-modified".
2401 ** New command -ada-task-info.
2403 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2404 $sdir specifies the default system locations of shared libraries.
2405 $pdir specifies the directory where the libpthread used by the application
2408 GDB no longer looks in $sdir and $pdir after it has searched the directories
2409 mentioned in libthread-db-search-path. If you want to search those
2410 directories, they must be specified in libthread-db-search-path.
2411 The default value of libthread-db-search-path on GNU/Linux and Solaris
2412 systems is now "$sdir:$pdir".
2414 $pdir is not supported by gdbserver, it is currently ignored.
2415 $sdir is supported by gdbserver.
2417 * New configure option --with-iconv-bin.
2418 When using the internationalization support like the one in the GNU C
2419 library, GDB will invoke the "iconv" program to get a list of supported
2420 character sets. If this program lives in a non-standard location, one can
2421 use this option to specify where to find it.
2423 * When natively debugging programs on PowerPC BookE processors running
2424 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2425 watchpoints, which specify a mask in addition to an address to watch.
2426 The mask specifies that some bits of an address (the bits which are
2427 reset in the mask) should be ignored when matching the address accessed
2428 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2429 section in the user manual for more details.
2431 * The new option --once causes GDBserver to stop listening for connections once
2432 the first connection is made. The listening port used by GDBserver will
2433 become available after that.
2435 * New commands "info macros" and "alias" have been added.
2437 * New function parameters suffix @entry specifies value of function parameter
2438 at the time the function got called. Entry values are available only since
2444 "!" is now an alias of the "shell" command.
2445 Note that no space is needed between "!" and SHELL COMMAND.
2449 watch EXPRESSION mask MASK_VALUE
2450 The watch command now supports the mask argument which allows creation
2451 of masked watchpoints, if the current architecture supports this feature.
2453 info auto-load-scripts [REGEXP]
2454 This command was formerly named "maintenance print section-scripts".
2455 It is now generally useful and is no longer a maintenance-only command.
2457 info macro [-all] [--] MACRO
2458 The info macro command has new options `-all' and `--'. The first for
2459 printing all definitions of a macro. The second for explicitly specifying
2460 the end of arguments and the beginning of the macro name in case the macro
2461 name starts with a hyphen.
2463 collect[/s] EXPRESSIONS
2464 The tracepoint collect command now takes an optional modifier "/s"
2465 that directs it to dereference pointer-to-character types and
2466 collect the bytes of memory up to a zero byte. The behavior is
2467 similar to what you see when you use the regular print command on a
2468 string. An optional integer following the "/s" sets a bound on the
2469 number of bytes that will be collected.
2472 The trace start command now interprets any supplied arguments as a
2473 note to be recorded with the trace run, with an effect similar to
2474 setting the variable trace-notes.
2477 The trace stop command now interprets any arguments as a note to be
2478 mentioned along with the tstatus report that the trace was stopped
2479 with a command. The effect is similar to setting the variable
2482 * Tracepoints can now be enabled and disabled at any time after a trace
2483 experiment has been started using the standard "enable" and "disable"
2484 commands. It is now possible to start a trace experiment with no enabled
2485 tracepoints; GDB will display a warning, but will allow the experiment to
2486 begin, assuming that tracepoints will be enabled as needed while the trace
2489 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2490 locations with 4-byte instructions, when they were previously
2491 limited to locations with instructions of 5 bytes or longer.
2495 set debug dwarf2-read
2496 show debug dwarf2-read
2497 Turns on or off display of debugging messages related to reading
2498 DWARF debug info. The default is off.
2500 set debug symtab-create
2501 show debug symtab-create
2502 Turns on or off display of debugging messages related to symbol table
2503 creation. The default is off.
2506 show extended-prompt
2507 Set the GDB prompt, and allow escape sequences to be inserted to
2508 display miscellaneous information (see 'help set extended-prompt'
2509 for the list of sequences). This prompt (and any information
2510 accessed through the escape sequences) is updated every time the
2511 prompt is displayed.
2513 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2514 show print entry-values
2515 Set printing of frame argument values at function entry. In some cases
2516 GDB can determine the value of function argument which was passed by the
2517 function caller, even if the value was modified inside the called function.
2519 set debug entry-values
2520 show debug entry-values
2521 Control display of debugging info for determining frame argument values at
2522 function entry and virtual tail call frames.
2524 set basenames-may-differ
2525 show basenames-may-differ
2526 Set whether a source file may have multiple base names.
2527 (A "base name" is the name of a file with the directory part removed.
2528 Example: The base name of "/home/user/hello.c" is "hello.c".)
2529 If set, GDB will canonicalize file names (e.g., expand symlinks)
2530 before comparing them. Canonicalization is an expensive operation,
2531 but it allows the same file be known by more than one base name.
2532 If not set (the default), all source files are assumed to have just
2533 one base name, and gdb will do file name comparisons more efficiently.
2539 Set a user name and notes for the current and any future trace runs.
2540 This is useful for long-running and/or disconnected traces, to
2541 inform others (or yourself) as to who is running the trace, supply
2542 contact information, or otherwise explain what is going on.
2544 set trace-stop-notes
2545 show trace-stop-notes
2546 Set a note attached to the trace run, that is displayed when the
2547 trace has been stopped by a tstop command. This is useful for
2548 instance as an explanation, if you are stopping a trace run that was
2549 started by someone else.
2551 * New remote packets
2555 Dynamically enable a tracepoint in a started trace experiment.
2559 Dynamically disable a tracepoint in a started trace experiment.
2563 Set the user and notes of the trace run.
2567 Query the current status of a tracepoint.
2571 Query the minimum length of instruction at which a fast tracepoint may
2574 * Dcache size (number of lines) and line-size are now runtime-configurable
2575 via "set dcache line" and "set dcache line-size" commands.
2579 Texas Instruments TMS320C6x tic6x-*-*
2583 Renesas RL78 rl78-*-elf
2585 *** Changes in GDB 7.3.1
2587 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2589 *** Changes in GDB 7.3
2591 * GDB has a new command: "thread find [REGEXP]".
2592 It finds the thread id whose name, target id, or thread extra info
2593 matches the given regular expression.
2595 * The "catch syscall" command now works on mips*-linux* targets.
2597 * The -data-disassemble MI command now supports modes 2 and 3 for
2598 dumping the instruction opcodes.
2600 * New command line options
2602 -data-directory DIR Specify DIR as the "data-directory".
2603 This is mostly for testing purposes.
2605 * The "maint set python auto-load on|off" command has been renamed to
2606 "set auto-load-scripts on|off".
2608 * GDB has a new command: "set directories".
2609 It is like the "dir" command except that it replaces the
2610 source path list instead of augmenting it.
2612 * GDB now understands thread names.
2614 On GNU/Linux, "info threads" will display the thread name as set by
2615 prctl or pthread_setname_np.
2617 There is also a new command, "thread name", which can be used to
2618 assign a name internally for GDB to display.
2621 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2622 has been integrated into GDB.
2626 ** The function gdb.Write now accepts an optional keyword 'stream'.
2627 This keyword, when provided, will direct the output to either
2628 stdout, stderr, or GDB's logging output.
2630 ** Parameters can now be be sub-classed in Python, and in particular
2631 you may implement the get_set_doc and get_show_doc functions.
2632 This improves how Parameter set/show documentation is processed
2633 and allows for more dynamic content.
2635 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2636 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2637 have an is_valid method.
2639 ** Breakpoints can now be sub-classed in Python, and in particular
2640 you may implement a 'stop' function that is executed each time
2641 the inferior reaches that breakpoint.
2643 ** New function gdb.lookup_global_symbol looks up a global symbol.
2645 ** GDB values in Python are now callable if the value represents a
2646 function. For example, if 'some_value' represents a function that
2647 takes two integer parameters and returns a value, you can call
2648 that function like so:
2650 result = some_value (10,20)
2652 ** Module gdb.types has been added.
2653 It contains a collection of utilities for working with gdb.Types objects:
2654 get_basic_type, has_field, make_enum_dict.
2656 ** Module gdb.printing has been added.
2657 It contains utilities for writing and registering pretty-printers.
2658 New classes: PrettyPrinter, SubPrettyPrinter,
2659 RegexpCollectionPrettyPrinter.
2660 New function: register_pretty_printer.
2662 ** New commands "info pretty-printers", "enable pretty-printer" and
2663 "disable pretty-printer" have been added.
2665 ** gdb.parameter("directories") is now available.
2667 ** New function gdb.newest_frame returns the newest frame in the
2670 ** The gdb.InferiorThread class has a new "name" attribute. This
2671 holds the thread's name.
2673 ** Python Support for Inferior events.
2674 Python scripts can add observers to be notified of events
2675 occurring in the process being debugged.
2676 The following events are currently supported:
2677 - gdb.events.cont Continue event.
2678 - gdb.events.exited Inferior exited event.
2679 - gdb.events.stop Signal received, and Breakpoint hit events.
2683 ** GDB now puts template parameters in scope when debugging in an
2684 instantiation. For example, if you have:
2686 template<int X> int func (void) { return X; }
2688 then if you step into func<5>, "print X" will show "5". This
2689 feature requires proper debuginfo support from the compiler; it
2690 was added to GCC 4.5.
2692 ** The motion commands "next", "finish", "until", and "advance" now
2693 work better when exceptions are thrown. In particular, GDB will
2694 no longer lose control of the inferior; instead, the GDB will
2695 stop the inferior at the point at which the exception is caught.
2696 This functionality requires a change in the exception handling
2697 code that was introduced in GCC 4.5.
2699 * GDB now follows GCC's rules on accessing volatile objects when
2700 reading or writing target state during expression evaluation.
2701 One notable difference to prior behavior is that "print x = 0"
2702 no longer generates a read of x; the value of the assignment is
2703 now always taken directly from the value being assigned.
2705 * GDB now has some support for using labels in the program's source in
2706 linespecs. For instance, you can use "advance label" to continue
2707 execution to a label.
2709 * GDB now has support for reading and writing a new .gdb_index
2710 section. This section holds a fast index of DWARF debugging
2711 information and can be used to greatly speed up GDB startup and
2712 operation. See the documentation for `save gdb-index' for details.
2714 * The "watch" command now accepts an optional "-location" argument.
2715 When used, this causes GDB to watch the memory referred to by the
2716 expression. Such a watchpoint is never deleted due to it going out
2719 * GDB now supports thread debugging of core dumps on GNU/Linux.
2721 GDB now activates thread debugging using the libthread_db library
2722 when debugging GNU/Linux core dumps, similarly to when debugging
2723 live processes. As a result, when debugging a core dump file, GDB
2724 is now able to display pthread_t ids of threads. For example, "info
2725 threads" shows the same output as when debugging the process when it
2726 was live. In earlier releases, you'd see something like this:
2729 * 1 LWP 6780 main () at main.c:10
2731 While now you see this:
2734 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2736 It is also now possible to inspect TLS variables when debugging core
2739 When debugging a core dump generated on a machine other than the one
2740 used to run GDB, you may need to point GDB at the correct
2741 libthread_db library with the "set libthread-db-search-path"
2742 command. See the user manual for more details on this command.
2744 * When natively debugging programs on PowerPC BookE processors running
2745 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2746 which stop execution of the inferior whenever it executes an instruction
2747 at any address within the specified range. See the "PowerPC Embedded"
2748 section in the user manual for more details.
2750 * New features in the GDB remote stub, GDBserver
2752 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2753 and i686 LynxOS (version 5.x).
2755 ** GDBserver is now supported on Blackfin Linux.
2757 * New native configurations
2759 ia64 HP-UX ia64-*-hpux*
2763 Analog Devices, Inc. Blackfin Processor bfin-*
2765 * Ada task switching is now supported on sparc-elf targets when
2766 debugging a program using the Ravenscar Profile. For more information,
2767 see the "Tasking Support when using the Ravenscar Profile" section
2768 in the GDB user manual.
2770 * Guile support was removed.
2772 * New features in the GNU simulator
2774 ** The --map-info flag lists all known core mappings.
2776 ** CFI flashes may be simulated via the "cfi" device.
2778 *** Changes in GDB 7.2
2780 * Shared library support for remote targets by default
2782 When GDB is configured for a generic, non-OS specific target, like
2783 for example, --target=arm-eabi or one of the many *-*-elf targets,
2784 GDB now queries remote stubs for loaded shared libraries using the
2785 `qXfer:libraries:read' packet. Previously, shared library support
2786 was always disabled for such configurations.
2790 ** Argument Dependent Lookup (ADL)
2792 In C++ ADL lookup directs function search to the namespaces of its
2793 arguments even if the namespace has not been imported.
2803 Here the compiler will search for `foo' in the namespace of 'b'
2804 and find A::foo. GDB now supports this. This construct is commonly
2805 used in the Standard Template Library for operators.
2807 ** Improved User Defined Operator Support
2809 In addition to member operators, GDB now supports lookup of operators
2810 defined in a namespace and imported with a `using' directive, operators
2811 defined in the global scope, operators imported implicitly from an
2812 anonymous namespace, and the ADL operators mentioned in the previous
2814 GDB now also supports proper overload resolution for all the previously
2815 mentioned flavors of operators.
2817 ** static const class members
2819 Printing of static const class members that are initialized in the
2820 class definition has been fixed.
2822 * Windows Thread Information Block access.
2824 On Windows targets, GDB now supports displaying the Windows Thread
2825 Information Block (TIB) structure. This structure is visible either
2826 by using the new command `info w32 thread-information-block' or, by
2827 dereferencing the new convenience variable named `$_tlb', a
2828 thread-specific pointer to the TIB. This feature is also supported
2829 when remote debugging using GDBserver.
2831 * Static tracepoints
2833 Static tracepoints are calls in the user program into a tracing
2834 library. One such library is a port of the LTTng kernel tracer to
2835 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2836 When debugging with GDBserver, GDB now supports combining the GDB
2837 tracepoint machinery with such libraries. For example: the user can
2838 use GDB to probe a static tracepoint marker (a call from the user
2839 program into the tracing library) with the new "strace" command (see
2840 "New commands" below). This creates a "static tracepoint" in the
2841 breakpoint list, that can be manipulated with the same feature set
2842 as fast and regular tracepoints. E.g., collect registers, local and
2843 global variables, collect trace state variables, and define
2844 tracepoint conditions. In addition, the user can collect extra
2845 static tracepoint marker specific data, by collecting the new
2846 $_sdata internal variable. When analyzing the trace buffer, you can
2847 inspect $_sdata like any other variable available to GDB. For more
2848 information, see the "Tracepoints" chapter in GDB user manual. New
2849 remote packets have been defined to support static tracepoints, see
2850 the "New remote packets" section below.
2852 * Better reconstruction of tracepoints after disconnected tracing
2854 GDB will attempt to download the original source form of tracepoint
2855 definitions when starting a trace run, and then will upload these
2856 upon reconnection to the target, resulting in a more accurate
2857 reconstruction of the tracepoints that are in use on the target.
2861 You can now exercise direct control over the ways that GDB can
2862 affect your program. For instance, you can disallow the setting of
2863 breakpoints, so that the program can run continuously (assuming
2864 non-stop mode). In addition, the "observer" variable is available
2865 to switch all of the different controls; in observer mode, GDB
2866 cannot affect the target's behavior at all, which is useful for
2867 tasks like diagnosing live systems in the field.
2869 * The new convenience variable $_thread holds the number of the
2872 * New remote packets
2876 Return the address of the Windows Thread Information Block of a given thread.
2880 In response to several of the tracepoint packets, the target may now
2881 also respond with a number of intermediate `qRelocInsn' request
2882 packets before the final result packet, to have GDB handle
2883 relocating an instruction to execute at a different address. This
2884 is particularly useful for stubs that support fast tracepoints. GDB
2885 reports support for this feature in the qSupported packet.
2889 List static tracepoint markers in the target program.
2893 List static tracepoint markers at a given address in the target
2896 qXfer:statictrace:read
2898 Read the static trace data collected (by a `collect $_sdata'
2899 tracepoint action). The remote stub reports support for this packet
2900 to gdb's qSupported query.
2904 Send the current settings of GDB's permission flags.
2908 Send part of the source (textual) form of a tracepoint definition,
2909 which includes location, conditional, and action list.
2911 * The source command now accepts a -s option to force searching for the
2912 script in the source search path even if the script name specifies
2915 * New features in the GDB remote stub, GDBserver
2917 - GDBserver now support tracepoints (including fast tracepoints, and
2918 static tracepoints). The feature is currently supported by the
2919 i386-linux and amd64-linux builds. See the "Tracepoints support
2920 in gdbserver" section in the manual for more information.
2922 GDBserver JIT compiles the tracepoint's conditional agent
2923 expression bytecode into native code whenever possible for low
2924 overhead dynamic tracepoints conditionals. For such tracepoints,
2925 an expression that examines program state is evaluated when the
2926 tracepoint is reached, in order to determine whether to capture
2927 trace data. If the condition is simple and false, processing the
2928 tracepoint finishes very quickly and no data is gathered.
2930 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2931 for static tracepoints support.
2933 - GDBserver now supports x86_64 Windows 64-bit debugging.
2935 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2936 it understands register description.
2938 * The --batch flag now disables pagination and queries.
2940 * X86 general purpose registers
2942 GDB now supports reading/writing byte, word and double-word x86
2943 general purpose registers directly. This means you can use, say,
2944 $ah or $ax to refer, respectively, to the byte register AH and
2945 16-bit word register AX that are actually portions of the 32-bit
2946 register EAX or 64-bit register RAX.
2948 * The `commands' command now accepts a range of breakpoints to modify.
2949 A plain `commands' following a command that creates multiple
2950 breakpoints affects all the breakpoints set by that command. This
2951 applies to breakpoints set by `rbreak', and also applies when a
2952 single `break' command creates multiple breakpoints (e.g.,
2953 breakpoints on overloaded c++ functions).
2955 * The `rbreak' command now accepts a filename specification as part of
2956 its argument, limiting the functions selected by the regex to those
2957 in the specified file.
2959 * Support for remote debugging Windows and SymbianOS shared libraries
2960 from Unix hosts has been improved. Non Windows GDB builds now can
2961 understand target reported file names that follow MS-DOS based file
2962 system semantics, such as file names that include drive letters and
2963 use the backslash character as directory separator. This makes it
2964 possible to transparently use the "set sysroot" and "set
2965 solib-search-path" on Unix hosts to point as host copies of the
2966 target's shared libraries. See the new command "set
2967 target-file-system-kind" described below, and the "Commands to
2968 specify files" section in the user manual for more information.
2972 eval template, expressions...
2973 Convert the values of one or more expressions under the control
2974 of the string template to a command line, and call it.
2976 set target-file-system-kind unix|dos-based|auto
2977 show target-file-system-kind
2978 Set or show the assumed file system kind for target reported file
2981 save breakpoints <filename>
2982 Save all current breakpoint definitions to a file suitable for use
2983 in a later debugging session. To read the saved breakpoint
2984 definitions, use the `source' command.
2986 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2989 info static-tracepoint-markers
2990 Display information about static tracepoint markers in the target.
2992 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2993 Define a static tracepoint by probing a marker at the given
2994 function, line, address, or marker ID.
2998 Enable and disable observer mode.
3000 set may-write-registers on|off
3001 set may-write-memory on|off
3002 set may-insert-breakpoints on|off
3003 set may-insert-tracepoints on|off
3004 set may-insert-fast-tracepoints on|off
3005 set may-interrupt on|off
3006 Set individual permissions for GDB effects on the target. Note that
3007 some of these settings can have undesirable or surprising
3008 consequences, particularly when changed in the middle of a session.
3009 For instance, disabling the writing of memory can prevent
3010 breakpoints from being inserted, cause single-stepping to fail, or
3011 even crash your program, if you disable after breakpoints have been
3012 inserted. However, GDB should not crash.
3014 set record memory-query on|off
3015 show record memory-query
3016 Control whether to stop the inferior if memory changes caused
3017 by an instruction cannot be recorded.
3022 The disassemble command now supports "start,+length" form of two arguments.
3026 ** GDB now provides a new directory location, called the python directory,
3027 where Python scripts written for GDB can be installed. The location
3028 of that directory is <data-directory>/python, where <data-directory>
3029 is the GDB data directory. For more details, see section `Scripting
3030 GDB using Python' in the manual.
3032 ** The GDB Python API now has access to breakpoints, symbols, symbol
3033 tables, program spaces, inferiors, threads and frame's code blocks.
3034 Additionally, GDB Parameters can now be created from the API, and
3035 manipulated via set/show in the CLI.
3037 ** New functions gdb.target_charset, gdb.target_wide_charset,
3038 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
3040 ** New exception gdb.GdbError.
3042 ** Pretty-printers are now also looked up in the current program space.
3044 ** Pretty-printers can now be individually enabled and disabled.
3046 ** GDB now looks for names of Python scripts to auto-load in a
3047 special section named `.debug_gdb_scripts', in addition to looking
3048 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
3050 * Tracepoint actions were unified with breakpoint commands. In particular,
3051 there are no longer differences in "info break" output for breakpoints and
3052 tracepoints and the "commands" command can be used for both tracepoints and
3053 regular breakpoints.
3057 ARM Symbian arm*-*-symbianelf*
3059 * D language support.
3060 GDB now supports debugging programs written in the D programming
3063 * GDB now supports the extended ptrace interface for PowerPC which is
3064 available since Linux kernel version 2.6.34. This automatically enables
3065 any hardware breakpoints and additional hardware watchpoints available in
3066 the processor. The old ptrace interface exposes just one hardware
3067 watchpoint and no hardware breakpoints.
3069 * GDB is now able to use the Data Value Compare (DVC) register available on
3070 embedded PowerPC processors to implement in hardware simple watchpoint
3071 conditions of the form:
3073 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
3075 This works in native GDB running on Linux kernels with the extended ptrace
3076 interface mentioned above.
3078 *** Changes in GDB 7.1
3082 ** Namespace Support
3084 GDB now supports importing of namespaces in C++. This enables the
3085 user to inspect variables from imported namespaces. Support for
3086 namepace aliasing has also been added. So, if a namespace is
3087 aliased in the current scope (e.g. namepace C=A; ) the user can
3088 print variables using the alias (e.g. (gdb) print C::x).
3092 All known bugs relating to the printing of virtual base class were
3093 fixed. It is now possible to call overloaded static methods using a
3098 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
3099 and reinterpret_cast<> are now handled by the C++ expression parser.
3103 Xilinx MicroBlaze microblaze-*-*
3108 Xilinx MicroBlaze microblaze
3111 * Multi-program debugging.
3113 GDB now has support for multi-program (a.k.a. multi-executable or
3114 multi-exec) debugging. This allows for debugging multiple inferiors
3115 simultaneously each running a different program under the same GDB
3116 session. See "Debugging Multiple Inferiors and Programs" in the
3117 manual for more information. This implied some user visible changes
3118 in the multi-inferior support. For example, "info inferiors" now
3119 lists inferiors that are not running yet or that have exited
3120 already. See also "New commands" and "New options" below.
3122 * New tracing features
3124 GDB's tracepoint facility now includes several new features:
3126 ** Trace state variables
3128 GDB tracepoints now include support for trace state variables, which
3129 are variables managed by the target agent during a tracing
3130 experiment. They are useful for tracepoints that trigger each
3131 other, so for instance one tracepoint can count hits in a variable,
3132 and then a second tracepoint has a condition that is true when the
3133 count reaches a particular value. Trace state variables share the
3134 $-syntax of GDB convenience variables, and can appear in both
3135 tracepoint actions and condition expressions. Use the "tvariable"
3136 command to create, and "info tvariables" to view; see "Trace State
3137 Variables" in the manual for more detail.
3141 GDB now includes an option for defining fast tracepoints, which
3142 targets may implement more efficiently, such as by installing a jump
3143 into the target agent rather than a trap instruction. The resulting
3144 speedup can be by two orders of magnitude or more, although the
3145 tradeoff is that some program locations on some target architectures
3146 might not allow fast tracepoint installation, for instance if the
3147 instruction to be replaced is shorter than the jump. To request a
3148 fast tracepoint, use the "ftrace" command, with syntax identical to
3149 the regular trace command.
3151 ** Disconnected tracing
3153 It is now possible to detach GDB from the target while it is running
3154 a trace experiment, then reconnect later to see how the experiment
3155 is going. In addition, a new variable disconnected-tracing lets you
3156 tell the target agent whether to continue running a trace if the
3157 connection is lost unexpectedly.
3161 GDB now has the ability to save the trace buffer into a file, and
3162 then use that file as a target, similarly to you can do with
3163 corefiles. You can select trace frames, print data that was
3164 collected in them, and use tstatus to display the state of the
3165 tracing run at the moment that it was saved. To create a trace
3166 file, use "tsave <filename>", and to use it, do "target tfile
3169 ** Circular trace buffer
3171 You can ask the target agent to handle the trace buffer as a
3172 circular buffer, discarding the oldest trace frames to make room for
3173 newer ones, by setting circular-trace-buffer to on. This feature may
3174 not be available for all target agents.
3179 The disassemble command, when invoked with two arguments, now requires
3180 the arguments to be comma-separated.
3183 The info variables command now displays variable definitions. Files
3184 which only declare a variable are not shown.
3187 The source command is now capable of sourcing Python scripts.
3188 This feature is dependent on the debugger being build with Python
3191 Related to this enhancement is also the introduction of a new command
3192 "set script-extension" (see below).
3194 * New commands (for set/show, see "New options" below)
3196 record save [<FILENAME>]
3197 Save a file (in core file format) containing the process record
3198 execution log for replay debugging at a later time.
3200 record restore <FILENAME>
3201 Restore the process record execution log that was saved at an
3202 earlier time, for replay debugging.
3204 add-inferior [-copies <N>] [-exec <FILENAME>]
3207 clone-inferior [-copies <N>] [ID]
3208 Make a new inferior ready to execute the same program another
3209 inferior has loaded.
3214 maint info program-spaces
3215 List the program spaces loaded into GDB.
3217 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
3218 show remote interrupt-sequence
3219 Allow the user to select one of ^C, a BREAK signal or BREAK-g
3220 as the sequence to the remote target in order to interrupt the execution.
3221 Ctrl-C is a default. Some system prefers BREAK which is high level of
3222 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
3223 Magic SysRq g. It is BREAK signal and character 'g'.
3225 set remote interrupt-on-connect [on | off]
3226 show remote interrupt-on-connect
3227 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
3228 remote target when gdb connects to it. This is needed when you debug
3231 set remotebreak [on | off]
3233 Deprecated. Use "set/show remote interrupt-sequence" instead.
3235 tvariable $NAME [ = EXP ]
3236 Create or modify a trace state variable.
3239 List trace state variables and their values.
3241 delete tvariable $NAME ...
3242 Delete one or more trace state variables.
3245 Evaluate the given expressions without collecting anything into the
3246 trace buffer. (Valid in tracepoint actions only.)
3248 ftrace FN / FILE:LINE / *ADDR
3249 Define a fast tracepoint at the given function, line, or address.
3251 * New expression syntax
3253 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
3254 GDB now parses 0b101010 identically with 42.
3258 set follow-exec-mode new|same
3259 show follow-exec-mode
3260 Control whether GDB reuses the same inferior across an exec call or
3261 creates a new one. This is useful to be able to restart the old
3262 executable after the inferior having done an exec call.
3264 set default-collect EXPR, ...
3265 show default-collect
3266 Define a list of expressions to be collected at each tracepoint.
3267 This is a useful way to ensure essential items are not overlooked,
3268 such as registers or a critical global variable.
3270 set disconnected-tracing
3271 show disconnected-tracing
3272 If set to 1, the target is instructed to continue tracing if it
3273 loses its connection to GDB. If 0, the target is to stop tracing
3276 set circular-trace-buffer
3277 show circular-trace-buffer
3278 If set to on, the target is instructed to use a circular trace buffer
3279 and discard the oldest trace frames instead of stopping the trace due
3280 to a full trace buffer. If set to off, the trace stops when the buffer
3281 fills up. Some targets may not support this.
3283 set script-extension off|soft|strict
3284 show script-extension
3285 If set to "off", the debugger does not perform any script language
3286 recognition, and all sourced files are assumed to be GDB scripts.
3287 If set to "soft" (the default), files are sourced according to
3288 filename extension, falling back to GDB scripts if the first
3290 If set to "strict", files are sourced according to filename extension.
3292 set ada trust-PAD-over-XVS on|off
3293 show ada trust-PAD-over-XVS
3294 If off, activate a workaround against a bug in the debugging information
3295 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
3296 the GCC sources for more information about the GNAT encoding and
3297 PAD types in particular). It is always safe to set this option to
3298 off, but this introduces a slight performance penalty. The default
3301 * Python API Improvements
3303 ** GDB provides the new class gdb.LazyString. This is useful in
3304 some pretty-printing cases. The new method gdb.Value.lazy_string
3305 provides a simple way to create objects of this type.
3307 ** The fields returned by gdb.Type.fields now have an
3308 `is_base_class' attribute.
3310 ** The new method gdb.Type.range returns the range of an array type.
3312 ** The new method gdb.parse_and_eval can be used to parse and
3313 evaluate an expression.
3315 * New remote packets
3318 Define a trace state variable.
3321 Get the current value of a trace state variable.
3324 Set desired tracing behavior upon disconnection.
3327 Set the trace buffer to be linear or circular.
3330 Get data about the tracepoints currently in use.
3334 Process record now works correctly with hardware watchpoints.
3336 Multiple bug fixes have been made to the mips-irix port, making it
3337 much more reliable. In particular:
3338 - Debugging threaded applications is now possible again. Previously,
3339 GDB would hang while starting the program, or while waiting for
3340 the program to stop at a breakpoint.
3341 - Attaching to a running process no longer hangs.
3342 - An error occurring while loading a core file has been fixed.
3343 - Changing the value of the PC register now works again. This fixes
3344 problems observed when using the "jump" command, or when calling
3345 a function from GDB, or even when assigning a new value to $pc.
3346 - With the "finish" and "return" commands, the return value for functions
3347 returning a small array is now correctly printed.
3348 - It is now possible to break on shared library code which gets executed
3349 during a shared library init phase (code executed while executing
3350 their .init section). Previously, the breakpoint would have no effect.
3351 - GDB is now able to backtrace through the signal handler for
3352 non-threaded programs.
3354 PIE (Position Independent Executable) programs debugging is now supported.
3355 This includes debugging execution of PIC (Position Independent Code) shared
3356 libraries although for that, it should be possible to run such libraries as an
3359 *** Changes in GDB 7.0
3361 * GDB now has an interface for JIT compilation. Applications that
3362 dynamically generate code can create symbol files in memory and register
3363 them with GDB. For users, the feature should work transparently, and
3364 for JIT developers, the interface is documented in the GDB manual in the
3365 "JIT Compilation Interface" chapter.
3367 * Tracepoints may now be conditional. The syntax is as for
3368 breakpoints; either an "if" clause appended to the "trace" command,
3369 or the "condition" command is available. GDB sends the condition to
3370 the target for evaluation using the same bytecode format as is used
3371 for tracepoint actions.
3373 * The disassemble command now supports: an optional /r modifier, print the
3374 raw instructions in hex as well as in symbolic form, and an optional /m
3375 modifier to print mixed source+assembly.
3377 * Process record and replay
3379 In a architecture environment that supports ``process record and
3380 replay'', ``process record and replay'' target can record a log of
3381 the process execution, and replay it with both forward and reverse
3384 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3385 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3386 set execution-direction {forward|reverse}, for targets that support
3389 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3390 feature is available with a native GDB running on kernel version
3393 * GDB now has support for multi-byte and wide character sets on the
3394 target. Strings whose character type is wchar_t, char16_t, or
3395 char32_t are now correctly printed. GDB supports wide- and unicode-
3396 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3397 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3398 `printf'. This feature requires iconv to work properly; if your
3399 system does not have a working iconv, GDB can use GNU libiconv. See
3400 the installation instructions for more information.
3402 * GDB now supports automatic retrieval of shared library files from
3403 remote targets. To use this feature, specify a system root that begins
3404 with the `remote:' prefix, either via the `set sysroot' command or via
3405 the `--with-sysroot' configure-time option.
3407 * "info sharedlibrary" now takes an optional regex of libraries to show,
3408 and it now reports if a shared library has no debugging information.
3410 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3411 now complete on file names.
3413 * When completing in expressions, gdb will attempt to limit
3414 completions to allowable structure or union fields, where appropriate.
3415 For instance, consider:
3417 # struct example { int f1; double f2; };
3418 # struct example variable;
3421 If the user types TAB at the end of this command line, the available
3422 completions will be "f1" and "f2".
3424 * Inlined functions are now supported. They show up in backtraces, and
3425 the "step", "next", and "finish" commands handle them automatically.
3427 * GDB now supports the token-splicing (##) and stringification (#)
3428 operators when expanding macros. It also supports variable-arity
3431 * GDB now supports inspecting extra signal information, exported by
3432 the new $_siginfo convenience variable. The feature is currently
3433 implemented on linux ARM, i386 and amd64.
3435 * GDB can now display the VFP floating point registers and NEON vector
3436 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3437 can provide these registers (requires Linux 2.6.30 or later). Remote
3438 and simulator targets may also provide them.
3440 * New remote packets
3443 Search memory for a sequence of bytes.
3446 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3447 operation over reliable transport links. Use of this packet is
3448 controlled by the `set remote noack-packet' command.
3451 Kill the process with the specified process ID. Use this in preference
3452 to `k' when multiprocess protocol extensions are supported.
3455 Obtains additional operating system information
3459 Read or write additional signal information.
3461 * Removed remote protocol undocumented extension
3463 An undocumented extension to the remote protocol's `S' stop reply
3464 packet that permited the stub to pass a process id was removed.
3465 Remote servers should use the `T' stop reply packet instead.
3467 * GDB now supports multiple function calling conventions according to the
3468 DWARF-2 DW_AT_calling_convention function attribute.
3470 * The SH target utilizes the aforementioned change to distinguish between gcc
3471 and Renesas calling convention. It also adds the new CLI commands
3472 `set/show sh calling-convention'.
3474 * GDB can now read compressed debug sections, as produced by GNU gold
3475 with the --compress-debug-sections=zlib flag.
3477 * 64-bit core files are now supported on AIX.
3479 * Thread switching is now supported on Tru64.
3481 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3482 which will be allocated using malloc later in program execution.
3484 * The qXfer:libraries:read remote procotol packet now allows passing a
3485 list of section offsets.
3487 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3488 conditions handling signals delivered during attach or thread creation
3489 have also been fixed.
3491 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3492 From the user's standpoint, all unqualified instances of True and False
3493 are treated as the standard definitions, regardless of context.
3495 * GDB now parses C++ symbol and type names more flexibly. For
3498 template<typename T> class C { };
3501 GDB will now correctly handle all of:
3503 ptype C<char const *>
3504 ptype C<char const*>
3505 ptype C<const char *>
3506 ptype C<const char*>
3508 * New features in the GDB remote stub, gdbserver
3510 - The "--wrapper" command-line argument tells gdbserver to use a
3511 wrapper program to launch programs for debugging.
3513 - On PowerPC and S/390 targets, it is now possible to use a single
3514 gdbserver executable to debug both 32-bit and 64-bit programs.
3515 (This requires gdbserver itself to be built as a 64-bit executable.)
3517 - gdbserver uses the new noack protocol mode for TCP connections to
3518 reduce communications latency, if also supported and enabled in GDB.
3520 - Support for the sparc64-linux-gnu target is now included in
3523 - The amd64-linux build of gdbserver now supports debugging both
3524 32-bit and 64-bit programs.
3526 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3527 now support hardware watchpoints, and will use them automatically
3532 GDB now has support for scripting using Python. Whether this is
3533 available is determined at configure time.
3535 New GDB commands can now be written in Python.
3537 * Ada tasking support
3539 Ada tasks can now be inspected in GDB. The following commands have
3543 Print the list of Ada tasks.
3545 Print detailed information about task number N.
3547 Print the task number of the current task.
3549 Switch the context of debugging to task number N.
3551 * Support for user-defined prefixed commands. The "define" command can
3552 add new commands to existing prefixes, e.g. "target".
3554 * Multi-inferior, multi-process debugging.
3556 GDB now has generalized support for multi-inferior debugging. See
3557 "Debugging Multiple Inferiors" in the manual for more information.
3558 Although availability still depends on target support, the command
3559 set is more uniform now. The GNU/Linux specific multi-forks support
3560 has been migrated to this new framework. This implied some user
3561 visible changes; see "New commands" and also "Removed commands"
3564 * Target descriptions can now describe the target OS ABI. See the
3565 "Target Description Format" section in the user manual for more
3568 * Target descriptions can now describe "compatible" architectures
3569 to indicate that the target can execute applications for a different
3570 architecture in addition to those for the main target architecture.
3571 See the "Target Description Format" section in the user manual for
3574 * Multi-architecture debugging.
3576 GDB now includes general supports for debugging applications on
3577 hybrid systems that use more than one single processor architecture
3578 at the same time. Each such hybrid architecture still requires
3579 specific support to be added. The only hybrid architecture supported
3580 in this version of GDB is the Cell Broadband Engine.
3582 * GDB now supports integrated debugging of Cell/B.E. applications that
3583 use both the PPU and SPU architectures. To enable support for hybrid
3584 Cell/B.E. debugging, you need to configure GDB to support both the
3585 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3586 --enable-targets configure option.
3588 * Non-stop mode debugging.
3590 For some targets, GDB now supports an optional mode of operation in
3591 which you can examine stopped threads while other threads continue
3592 to execute freely. This is referred to as non-stop mode, with the
3593 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3594 section in the user manual for more information.
3596 To be able to support remote non-stop debugging, a remote stub needs
3597 to implement the non-stop mode remote protocol extensions, as
3598 described in the "Remote Non-Stop" section of the user manual. The
3599 GDB remote stub, gdbserver, has been adjusted to support these
3600 extensions on linux targets.
3602 * New commands (for set/show, see "New options" below)
3604 catch syscall [NAME(S) | NUMBER(S)]
3605 Catch system calls. Arguments, which should be names of system
3606 calls or their numbers, mean catch only those syscalls. Without
3607 arguments, every syscall will be caught. When the inferior issues
3608 any of the specified syscalls, GDB will stop and announce the system
3609 call, both when it is called and when its call returns. This
3610 feature is currently available with a native GDB running on the
3611 Linux Kernel, under the following architectures: x86, x86_64,
3612 PowerPC and PowerPC64.
3614 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3616 Search memory for a sequence of bytes.
3618 maint set python print-stack
3619 maint show python print-stack
3620 Show a stack trace when an error is encountered in a Python script.
3623 Invoke CODE by passing it to the Python interpreter.
3628 These allow macros to be defined, undefined, and listed
3632 Show operating system information about processes.
3635 List the inferiors currently under GDB's control.
3638 Switch focus to inferior number NUM.
3641 Detach from inferior number NUM.
3644 Kill inferior number NUM.
3648 set spu stop-on-load
3649 show spu stop-on-load
3650 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3652 set spu auto-flush-cache
3653 show spu auto-flush-cache
3654 Control whether to automatically flush the software-managed cache
3655 during Cell/B.E. debugging.
3657 set sh calling-convention
3658 show sh calling-convention
3659 Control the calling convention used when calling SH target functions.
3662 show debug timestamp
3663 Control display of timestamps with GDB debugging output.
3665 set disassemble-next-line
3666 show disassemble-next-line
3667 Control display of disassembled source lines or instructions when
3670 set remote noack-packet
3671 show remote noack-packet
3672 Set/show the use of remote protocol QStartNoAckMode packet. See above
3673 under "New remote packets."
3675 set remote query-attached-packet
3676 show remote query-attached-packet
3677 Control use of remote protocol `qAttached' (query-attached) packet.
3679 set remote read-siginfo-object
3680 show remote read-siginfo-object
3681 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3684 set remote write-siginfo-object
3685 show remote write-siginfo-object
3686 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3689 set remote reverse-continue
3690 show remote reverse-continue
3691 Control use of remote protocol 'bc' (reverse-continue) packet.
3693 set remote reverse-step
3694 show remote reverse-step
3695 Control use of remote protocol 'bs' (reverse-step) packet.
3697 set displaced-stepping
3698 show displaced-stepping
3699 Control displaced stepping mode. Displaced stepping is a way to
3700 single-step over breakpoints without removing them from the debuggee.
3701 Also known as "out-of-line single-stepping".
3704 show debug displaced
3705 Control display of debugging info for displaced stepping.
3707 maint set internal-error
3708 maint show internal-error
3709 Control what GDB does when an internal error is detected.
3711 maint set internal-warning
3712 maint show internal-warning
3713 Control what GDB does when an internal warning is detected.
3718 Use a wrapper program to launch programs for debugging.
3720 set multiple-symbols (all|ask|cancel)
3721 show multiple-symbols
3722 The value of this variable can be changed to adjust the debugger behavior
3723 when an expression or a breakpoint location contains an ambiguous symbol
3724 name (an overloaded function name, for instance).
3726 set breakpoint always-inserted
3727 show breakpoint always-inserted
3728 Keep breakpoints always inserted in the target, as opposed to inserting
3729 them when resuming the target, and removing them when the target stops.
3730 This option can improve debugger performance on slow remote targets.
3732 set arm fallback-mode (arm|thumb|auto)
3733 show arm fallback-mode
3734 set arm force-mode (arm|thumb|auto)
3736 These commands control how ARM GDB determines whether instructions
3737 are ARM or Thumb. The default for both settings is auto, which uses
3738 the current CPSR value for instructions without symbols; previous
3739 versions of GDB behaved as if "set arm fallback-mode arm".
3741 set disable-randomization
3742 show disable-randomization
3743 Standalone programs run with the virtual address space randomization enabled
3744 by default on some platforms. This option keeps the addresses stable across
3745 multiple debugging sessions.
3749 Control whether other threads are stopped or not when some thread hits
3754 Requests that asynchronous execution is enabled in the target, if available.
3755 In this case, it's possible to resume target in the background, and interact
3756 with GDB while the target is running. "show target-async" displays the
3757 current state of asynchronous execution of the target.
3759 set target-wide-charset
3760 show target-wide-charset
3761 The target-wide-charset is the name of the character set that GDB
3762 uses when printing characters whose type is wchar_t.
3764 set tcp auto-retry (on|off)
3766 set tcp connect-timeout
3767 show tcp connect-timeout
3768 These commands allow GDB to retry failed TCP connections to a remote stub
3769 with a specified timeout period; this is useful if the stub is launched
3770 in parallel with GDB but may not be ready to accept connections immediately.
3772 set libthread-db-search-path
3773 show libthread-db-search-path
3774 Control list of directories which GDB will search for appropriate
3777 set schedule-multiple (on|off)
3778 show schedule-multiple
3779 Allow GDB to resume all threads of all processes or only threads of
3780 the current process.
3784 Use more aggressive caching for accesses to the stack. This improves
3785 performance of remote debugging (particularly backtraces) without
3786 affecting correctness.
3788 set interactive-mode (on|off|auto)
3789 show interactive-mode
3790 Control whether GDB runs in interactive mode (on) or not (off).
3791 When in interactive mode, GDB waits for the user to answer all
3792 queries. Otherwise, GDB does not wait and assumes the default
3793 answer. When set to auto (the default), GDB determines which
3794 mode to use based on the stdin settings.
3799 For program forks, this is replaced by the new more generic `info
3800 inferiors' command. To list checkpoints, you can still use the
3801 `info checkpoints' command, which was an alias for the `info forks'
3805 Replaced by the new `inferior' command. To switch between
3806 checkpoints, you can still use the `restart' command, which was an
3807 alias for the `fork' command.
3810 This is removed, since some targets don't have a notion of
3811 processes. To switch between processes, you can still use the
3812 `inferior' command using GDB's own inferior number.
3815 For program forks, this is replaced by the new more generic `kill
3816 inferior' command. To delete a checkpoint, you can still use the
3817 `delete checkpoint' command, which was an alias for the `delete
3821 For program forks, this is replaced by the new more generic `detach
3822 inferior' command. To detach a checkpoint, you can still use the
3823 `detach checkpoint' command, which was an alias for the `detach
3826 * New native configurations
3828 x86/x86_64 Darwin i[34567]86-*-darwin*
3830 x86_64 MinGW x86_64-*-mingw*
3834 Lattice Mico32 lm32-*
3835 x86 DICOS i[34567]86-*-dicos*
3836 x86_64 DICOS x86_64-*-dicos*
3839 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3840 (mingw32ce) debugging.
3846 These commands were actually not implemented on any target.
3848 *** Changes in GDB 6.8
3850 * New native configurations
3852 NetBSD/hppa hppa*-*netbsd*
3853 Xtensa GNU/Linux xtensa*-*-linux*
3857 NetBSD/hppa hppa*-*-netbsd*
3858 Xtensa GNU/Lunux xtensa*-*-linux*
3860 * Change in command line behavior -- corefiles vs. process ids.
3862 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3863 attaching to process NUMBER fails, GDB no longer attempts to open a
3864 core file named NUMBER. Attaching to a program using the -c option
3865 is no longer supported. Instead, use the '-p' or '--pid' options.
3867 * GDB can now be built as a native debugger for debugging Windows x86
3868 (mingw32) Portable Executable (PE) programs.
3870 * Pending breakpoints no longer change their number when their address
3873 * GDB now supports breakpoints with multiple locations,
3874 including breakpoints on C++ constructors, inside C++ templates,
3875 and in inlined functions.
3877 * GDB's ability to debug optimized code has been improved. GDB more
3878 accurately identifies function bodies and lexical blocks that occupy
3879 more than one contiguous range of addresses.
3881 * Target descriptions can now describe registers for PowerPC.
3883 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3884 registers on PowerPC targets.
3886 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3887 targets even when the libthread_db library is not available.
3889 * The GDB remote stub, gdbserver, now supports the new file transfer
3890 commands (remote put, remote get, and remote delete).
3892 * The GDB remote stub, gdbserver, now supports run and attach in
3893 extended-remote mode.
3895 * hppa*64*-*-hpux11* target broken
3896 The debugger is unable to start a program and fails with the following
3897 error: "Error trying to get information about dynamic linker".
3898 The gdb-6.7 release is also affected.
3900 * GDB now supports the --enable-targets= configure option to allow
3901 building a single GDB executable that supports multiple remote
3902 target architectures.
3904 * GDB now supports debugging C and C++ programs which use the
3905 Decimal Floating Point extension. In addition, the PowerPC target
3906 now has a set of pseudo-registers to inspect decimal float values
3907 stored in two consecutive float registers.
3909 * The -break-insert MI command can optionally create pending
3912 * Improved support for debugging Ada
3913 Many improvements to the Ada language support have been made. These
3915 - Better support for Ada2005 interface types
3916 - Improved handling of arrays and slices in general
3917 - Better support for Taft-amendment types
3918 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3920 - Improved command completion in Ada
3923 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3928 set print frame-arguments (all|scalars|none)
3929 show print frame-arguments
3930 The value of this variable can be changed to control which argument
3931 values should be printed by the debugger when displaying a frame.
3936 Transfer files to and from a remote target, and delete remote files.
3943 Transfer files to and from a remote target, and delete remote files.
3945 * New remote packets
3952 Open, close, read, write, and delete files on the remote system.
3955 Attach to an existing process on the remote system, in extended-remote
3959 Run a new process on the remote system, in extended-remote mode.
3961 *** Changes in GDB 6.7
3963 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3964 bfd, libiberty and opcodes, as revealed by static analysis donated by
3965 Coverity, Inc. (http://scan.coverity.com).
3967 * When looking up multiply-defined global symbols, GDB will now prefer the
3968 symbol definition in the current shared library if it was built using the
3969 -Bsymbolic linker option.
3971 * When the Text User Interface (TUI) is not configured, GDB will now
3972 recognize the -tui command-line option and print a message that the TUI
3975 * The GDB remote stub, gdbserver, now has lower overhead for high
3976 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3978 * GDB for MIPS targets now autodetects whether a remote target provides
3979 32-bit or 64-bit register values.
3981 * Support for C++ member pointers has been improved.
3983 * GDB now understands XML target descriptions, which specify the
3984 target's overall architecture. GDB can read a description from
3985 a local file or over the remote serial protocol.
3987 * Vectors of single-byte data use a new integer type which is not
3988 automatically displayed as character or string data.
3990 * The /s format now works with the print command. It displays
3991 arrays of single-byte integers and pointers to single-byte integers
3994 * Target descriptions can now describe target-specific registers,
3995 for architectures which have implemented the support (currently
3996 only ARM, M68K, and MIPS).
3998 * GDB and the GDB remote stub, gdbserver, now support the XScale
4001 * The GDB remote stub, gdbserver, has been updated to support
4002 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
4003 has been rewritten to use the standard GDB remote protocol.
4005 * GDB can now step into C++ functions which are called through thunks.
4007 * GDB for the Cell/B.E. SPU now supports overlay debugging.
4009 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
4010 layout. It also supports a TextSeg= and DataSeg= response when only
4011 segment base addresses (rather than offsets) are available.
4013 * The /i format now outputs any trailing branch delay slot instructions
4014 immediately following the last instruction within the count specified.
4016 * The GDB remote protocol "T" stop reply packet now supports a
4017 "library" response. Combined with the new "qXfer:libraries:read"
4018 packet, this response allows GDB to debug shared libraries on targets
4019 where the operating system manages the list of loaded libraries (e.g.
4020 Windows and SymbianOS).
4022 * The GDB remote stub, gdbserver, now supports dynamic link libraries
4023 (DLLs) on Windows and Windows CE targets.
4025 * GDB now supports a faster verification that a .debug file matches its binary
4026 according to its build-id signature, if the signature is present.
4032 Enable or disable hardware flow control (RTS/CTS) on the serial port
4033 when debugging using remote targets.
4035 set mem inaccessible-by-default
4036 show mem inaccessible-by-default
4037 If the target supplies a memory map, for instance via the remote
4038 protocol's "qXfer:memory-map:read" packet, setting this variable
4039 prevents GDB from accessing memory outside the memory map. This
4040 is useful for targets with memory mapped registers or which react
4041 badly to accesses of unmapped address space.
4043 set breakpoint auto-hw
4044 show breakpoint auto-hw
4045 If the target supplies a memory map, for instance via the remote
4046 protocol's "qXfer:memory-map:read" packet, setting this variable
4047 lets GDB use hardware breakpoints automatically for memory regions
4048 where it can not use software breakpoints. This covers both the
4049 "break" command and internal breakpoints used for other commands
4050 including "next" and "finish".
4053 catch exception unhandled
4054 Stop the program execution when Ada exceptions are raised.
4057 Stop the program execution when an Ada assertion failed.
4061 Set an alternate system root for target files. This is a more
4062 general version of "set solib-absolute-prefix", which is now
4063 an alias to "set sysroot".
4066 Provide extended SPU facility status information. This set of
4067 commands is available only when debugging the Cell/B.E. SPU
4070 * New native configurations
4072 OpenBSD/sh sh*-*openbsd*
4075 unset tdesc filename
4077 Use the specified local file as an XML target description, and do
4078 not query the target for its built-in description.
4082 OpenBSD/sh sh*-*-openbsd*
4083 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
4084 Toshiba Media Processor mep-elf
4086 * New remote packets
4089 Ignore the specified signals; pass them directly to the debugged program
4090 without stopping other threads or reporting them to GDB.
4092 qXfer:features:read:
4093 Read an XML target description from the target, which describes its
4098 Read or write contents of an spufs file on the target system. These
4099 packets are available only on the Cell/B.E. SPU architecture.
4101 qXfer:libraries:read:
4102 Report the loaded shared libraries. Combined with new "T" packet
4103 response, this packet allows GDB to debug shared libraries on
4104 targets where the operating system manages the list of loaded
4105 libraries (e.g. Windows and SymbianOS).
4109 Support for these obsolete configurations has been removed.
4117 i[34567]86-*-lynxos*
4118 i[34567]86-*-netware*
4119 i[34567]86-*-sco3.2v5*
4120 i[34567]86-*-sco3.2v4*
4122 i[34567]86-*-sysv4.2*
4125 i[34567]86-*-unixware2*
4126 i[34567]86-*-unixware*
4135 * Other removed features
4142 Various m68k-only ROM monitors.
4149 Various Renesas ROM monitors and debugging interfaces for SH and
4154 Support for a Macraigor serial interface to on-chip debugging.
4155 GDB does not directly support the newer parallel or USB
4160 A debug information format. The predecessor to DWARF 2 and
4161 DWARF 3, which are still supported.
4163 Support for the HP aCC compiler on HP-UX/PA-RISC
4165 SOM-encapsulated symbolic debugging information, automatic
4166 invocation of pxdb, and the aCC custom C++ ABI. This does not
4167 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
4168 with aCC can still be debugged on an assembly level.
4170 MIPS ".pdr" sections
4172 A MIPS-specific format used to describe stack frame layout
4173 in debugging information.
4177 GDB could work with an older version of Guile to debug
4178 the interpreter and Scheme programs running in it.
4180 set mips stack-arg-size
4181 set mips saved-gpreg-size
4183 Use "set mips abi" to control parameter passing for MIPS.
4185 *** Changes in GDB 6.6
4190 Cell Broadband Engine SPU spu-elf
4192 * GDB can now be configured as a cross-debugger targeting native Windows
4193 (mingw32) or Cygwin. It can communicate with a remote debugging stub
4194 running on a Windows system over TCP/IP to debug Windows programs.
4196 * The GDB remote stub, gdbserver, has been updated to support Windows and
4197 Cygwin debugging. Both single-threaded and multi-threaded programs are
4200 * The "set trust-readonly-sections" command works again. This command was
4201 broken in GDB 6.3, 6.4, and 6.5.
4203 * The "load" command now supports writing to flash memory, if the remote
4204 stub provides the required support.
4206 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
4207 longer requires symbolic debug information (e.g. DWARF-2).
4212 unset substitute-path
4213 show substitute-path
4214 Manage a list of substitution rules that GDB uses to rewrite the name
4215 of the directories where the sources are located. This can be useful
4216 for instance when the sources were moved to a different location
4217 between compilation and debugging.
4221 Print each CLI command as it is executed. Each command is prefixed with
4222 a number of `+' symbols representing the nesting depth.
4223 The source command now has a `-v' option to enable the same feature.
4227 The ARM Demon monitor support (RDP protocol, "target rdp").
4229 Kernel Object Display, an embedded debugging feature which only worked with
4230 an obsolete version of Cisco IOS.
4232 The 'set download-write-size' and 'show download-write-size' commands.
4234 * New remote packets
4237 Tell a stub about GDB client features, and request remote target features.
4238 The first feature implemented is PacketSize, which allows the target to
4239 specify the size of packets it can handle - to minimize the number of
4240 packets required and improve performance when connected to a remote
4244 Fetch an OS auxilliary vector from the remote stub. This packet is a
4245 more efficient replacement for qPart:auxv:read.
4247 qXfer:memory-map:read:
4248 Fetch a memory map from the remote stub, including information about
4249 RAM, ROM, and flash memory devices.
4254 Erase and program a flash memory device.
4256 * Removed remote packets
4259 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
4260 used it, and only gdbserver implemented it.
4262 *** Changes in GDB 6.5
4266 Renesas M32C/M16C m32c-elf
4268 Morpho Technologies ms1 ms1-elf
4272 init-if-undefined Initialize a convenience variable, but
4273 only if it doesn't already have a value.
4275 The following commands are presently only implemented for native GNU/Linux:
4277 checkpoint Save a snapshot of the program state.
4279 restart <n> Return the program state to a
4280 previously saved state.
4282 info checkpoints List currently saved checkpoints.
4284 delete-checkpoint <n> Delete a previously saved checkpoint.
4286 set|show detach-on-fork Tell gdb whether to detach from a newly
4287 forked process, or to keep debugging it.
4289 info forks List forks of the user program that
4290 are available to be debugged.
4292 fork <n> Switch to debugging one of several
4293 forks of the user program that are
4294 available to be debugged.
4296 delete-fork <n> Delete a fork from the list of forks
4297 that are available to be debugged (and
4298 kill the forked process).
4300 detach-fork <n> Delete a fork from the list of forks
4301 that are available to be debugged (and
4302 allow the process to continue).
4306 Morpho Technologies ms2 ms1-elf
4308 * Improved Windows host support
4310 GDB now builds as a cross debugger hosted on i686-mingw32, including
4311 native console support, and remote communications using either
4312 network sockets or serial ports.
4314 * Improved Modula-2 language support
4316 GDB can now print most types in the Modula-2 syntax. This includes:
4317 basic types, set types, record types, enumerated types, range types,
4318 pointer types and ARRAY types. Procedure var parameters are correctly
4319 printed and hexadecimal addresses and character constants are also
4320 written in the Modula-2 syntax. Best results can be obtained by using
4321 GNU Modula-2 together with the -gdwarf-2 command line option.
4325 The ARM rdi-share module.
4327 The Netware NLM debug server.
4329 *** Changes in GDB 6.4
4331 * New native configurations
4333 OpenBSD/arm arm*-*-openbsd*
4334 OpenBSD/mips64 mips64-*-openbsd*
4338 Morpho Technologies ms1 ms1-elf
4340 * New command line options
4342 --batch-silent As for --batch, but totally silent.
4343 --return-child-result The debugger will exist with the same value
4344 the child (debugged) program exited with.
4345 --eval-command COMMAND, -ex COMMAND
4346 Execute a single GDB CLI command. This may be
4347 specified multiple times and in conjunction
4348 with the --command (-x) option.
4350 * Deprecated commands removed
4352 The following commands, that were deprecated in 2000, have been
4356 set|show arm disassembly-flavor set|show arm disassembler
4357 othernames set arm disassembler
4358 set|show remotedebug set|show debug remote
4359 set|show archdebug set|show debug arch
4360 set|show eventdebug set|show debug event
4363 * New BSD user-level threads support
4365 It is now possible to debug programs using the user-level threads
4366 library on OpenBSD and FreeBSD. Currently supported (target)
4369 FreeBSD/amd64 x86_64-*-freebsd*
4370 FreeBSD/i386 i386-*-freebsd*
4371 OpenBSD/i386 i386-*-openbsd*
4373 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4374 are not yet supported.
4376 * New support for Matsushita MN10300 w/sim added
4377 (Work in progress). mn10300-elf.
4379 * REMOVED configurations and files
4381 VxWorks and the XDR protocol *-*-vxworks
4382 Motorola MCORE mcore-*-*
4383 National Semiconductor NS32000 ns32k-*-*
4385 * New "set print array-indexes" command
4387 After turning this setting "on", GDB prints the index of each element
4388 when displaying arrays. The default is "off" to preserve the previous
4391 * VAX floating point support
4393 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4395 * User-defined command support
4397 In addition to using $arg0..$arg9 for argument passing, it is now possible
4398 to use $argc to determine now many arguments have been passed. See the
4399 section on user-defined commands in the user manual for more information.
4401 *** Changes in GDB 6.3:
4403 * New command line option
4405 GDB now accepts -l followed by a number to set the timeout for remote
4408 * GDB works with GCC -feliminate-dwarf2-dups
4410 GDB now supports a more compact representation of DWARF-2 debug
4411 information using DW_FORM_ref_addr references. These are produced
4412 by GCC with the option -feliminate-dwarf2-dups and also by some
4413 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4414 to use -feliminate-dwarf2-dups.
4416 * Internationalization
4418 When supported by the host system, GDB will be built with
4419 internationalization (libintl). The task of marking up the sources is
4420 continued, we're looking forward to our first translation.
4424 Initial support for debugging programs compiled with the GNAT
4425 implementation of the Ada programming language has been integrated
4426 into GDB. In this release, support is limited to expression evaluation.
4428 * New native configurations
4430 GNU/Linux/m32r m32r-*-linux-gnu
4434 GDB's remote protocol now includes support for the 'p' packet. This
4435 packet is used to fetch individual registers from a remote inferior.
4437 * END-OF-LIFE registers[] compatibility module
4439 GDB's internal register infrastructure has been completely rewritten.
4440 The new infrastructure making possible the implementation of key new
4441 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4444 GDB 6.3 will be the last release to include the the registers[]
4445 compatibility module that allowed out-of-date configurations to
4446 continue to work. This change directly impacts the following
4456 powerpc bdm protocol
4458 Unless there is activity to revive these configurations, they will be
4459 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4461 * OBSOLETE configurations and files
4463 Configurations that have been declared obsolete in this release have
4464 been commented out. Unless there is activity to revive these
4465 configurations, the next release of GDB will have their sources
4466 permanently REMOVED.
4475 *** Changes in GDB 6.2.1:
4477 * MIPS `break main; run' gave an heuristic-fence-post warning
4479 When attempting to run even a simple program, a warning about
4480 heuristic-fence-post being hit would be reported. This problem has
4483 * MIPS IRIX 'long double' crashed GDB
4485 When examining a long double variable, GDB would get a segmentation
4486 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4487 IRIX long double values).
4491 A bug in the VAX stack code was causing problems with the "next"
4492 command. This problem has been fixed.
4494 *** Changes in GDB 6.2:
4496 * Fix for ``many threads''
4498 On GNU/Linux systems that use the NPTL threads library, a program
4499 rapidly creating and deleting threads would confuse GDB leading to the
4502 ptrace: No such process.
4503 thread_db_get_info: cannot get thread info: generic error
4505 This problem has been fixed.
4507 * "-async" and "-noasync" options removed.
4509 Support for the broken "-noasync" option has been removed (it caused
4512 * New ``start'' command.
4514 This command runs the program until the begining of the main procedure.
4516 * New BSD Kernel Data Access Library (libkvm) interface
4518 Using ``target kvm'' it is now possible to debug kernel core dumps and
4519 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4520 platforms. Currently supported (native-only) configurations are:
4522 FreeBSD/amd64 x86_64-*-freebsd*
4523 FreeBSD/i386 i?86-*-freebsd*
4524 NetBSD/i386 i?86-*-netbsd*
4525 NetBSD/m68k m68*-*-netbsd*
4526 NetBSD/sparc sparc-*-netbsd*
4527 OpenBSD/amd64 x86_64-*-openbsd*
4528 OpenBSD/i386 i?86-*-openbsd*
4529 OpenBSD/m68k m68*-openbsd*
4530 OpenBSD/sparc sparc-*-openbsd*
4532 * Signal trampoline code overhauled
4534 Many generic problems with GDB's signal handling code have been fixed.
4535 These include: backtraces through non-contiguous stacks; recognition
4536 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4537 call; backtrace through a signal trampoline; step into and out of
4538 signal handlers; and single-stepping in the signal trampoline.
4540 Please note that kernel bugs are a limiting factor here. These
4541 features have been shown to work on an s390 GNU/Linux system that
4542 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4544 * Cygwin support for DWARF 2 added.
4546 * New native configurations
4548 GNU/Linux/hppa hppa*-*-linux*
4549 OpenBSD/hppa hppa*-*-openbsd*
4550 OpenBSD/m68k m68*-*-openbsd*
4551 OpenBSD/m88k m88*-*-openbsd*
4552 OpenBSD/powerpc powerpc-*-openbsd*
4553 NetBSD/vax vax-*-netbsd*
4554 OpenBSD/vax vax-*-openbsd*
4556 * END-OF-LIFE frame compatibility module
4558 GDB's internal frame infrastructure has been completely rewritten.
4559 The new infrastructure making it possible to support key new features
4560 including DWARF 2 Call Frame Information. To aid in the task of
4561 migrating old configurations to this new infrastructure, a
4562 compatibility module, that allowed old configurations to continue to
4563 work, was also included.
4565 GDB 6.2 will be the last release to include this frame compatibility
4566 module. This change directly impacts the following configurations:
4576 Unless there is activity to revive these configurations, they will be
4577 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4579 * REMOVED configurations and files
4581 Sun 3, running SunOS 3 m68*-*-sunos3*
4582 Sun 3, running SunOS 4 m68*-*-sunos4*
4583 Sun 2, running SunOS 3 m68000-*-sunos3*
4584 Sun 2, running SunOS 4 m68000-*-sunos4*
4585 Motorola 680x0 running LynxOS m68*-*-lynxos*
4586 AT&T 3b1/Unix pc m68*-att-*
4587 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4588 decstation mips-dec-* mips-little-*
4589 riscos mips-*-riscos* mips-*-sysv*
4590 sonymips mips-sony-*
4591 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4593 *** Changes in GDB 6.1.1:
4595 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4597 The TUI (Text-mode User Interface) is now built as part of a default
4598 GDB configuration. It is enabled by either selecting the TUI with the
4599 command line option "-i=tui" or by running the separate "gdbtui"
4600 program. For more information on the TUI, see the manual "Debugging
4603 * Pending breakpoint support (also included in GDB 6.1)
4605 Support has been added to allow you to specify breakpoints in shared
4606 libraries that have not yet been loaded. If a breakpoint location
4607 cannot be found, and the "breakpoint pending" option is set to auto,
4608 GDB queries you if you wish to make the breakpoint pending on a future
4609 shared-library load. If and when GDB resolves the breakpoint symbol,
4610 the pending breakpoint is removed as one or more regular breakpoints
4613 Pending breakpoints are very useful for GCJ Java debugging.
4615 * Fixed ISO-C build problems
4617 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4618 non ISO-C code that stopped them being built using a more strict ISO-C
4619 compiler (e.g., IBM's C compiler).
4621 * Fixed build problem on IRIX 5
4623 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4624 wasn't able to compile compile on an IRIX 5 system.
4626 * Added execute permission to gdb/gdbserver/configure
4628 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4629 permission. This bug would cause configure to fail on a number of
4630 systems (Solaris, IRIX). Ref: server/519.
4632 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4634 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4635 has been updated to use constant array sizes.
4637 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4639 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4640 its generated DWARF Call Frame Info. This encoding was causing GDB to
4641 panic, that panic has been fixed. Ref: gdb/1628.
4643 * Fixed a problem when examining parameters in shared library code.
4645 When examining parameters in optimized shared library code generated
4646 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4647 not available''. GDB now correctly displays the variable's value.
4649 *** Changes in GDB 6.1:
4651 * Removed --with-mmalloc
4653 Support for the mmalloc memory manager has been removed, as it
4654 conflicted with the internal gdb byte cache.
4656 * Changes in AMD64 configurations
4658 The AMD64 target now includes the %cs and %ss registers. As a result
4659 the AMD64 remote protocol has changed; this affects the floating-point
4660 and SSE registers. If you rely on those registers for your debugging,
4661 you should upgrade gdbserver on the remote side.
4663 * Revised SPARC target
4665 The SPARC target has been completely revised, incorporating the
4666 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4667 support for LynxOS and SunOS 4 has been dropped. Calling functions
4668 from within GDB on operating systems with a non-executable stack
4669 (Solaris, OpenBSD) now works.
4673 GDB has a new C++ demangler which does a better job on the mangled
4674 names generated by current versions of g++. It also runs faster, so
4675 with this and other changes gdb should now start faster on large C++
4678 * DWARF 2 Location Expressions
4680 GDB support for location expressions has been extended to support function
4681 arguments and frame bases. Older versions of GDB could crash when they
4684 * C++ nested types and namespaces
4686 GDB's support for nested types and namespaces in C++ has been
4687 improved, especially if you use the DWARF 2 debugging format. (This
4688 is the default for recent versions of GCC on most platforms.)
4689 Specifically, if you have a class "Inner" defined within a class or
4690 namespace "Outer", then GDB realizes that the class's name is
4691 "Outer::Inner", not simply "Inner". This should greatly reduce the
4692 frequency of complaints about not finding RTTI symbols. In addition,
4693 if you are stopped at inside of a function defined within a namespace,
4694 GDB modifies its name lookup accordingly.
4696 * New native configurations
4698 NetBSD/amd64 x86_64-*-netbsd*
4699 OpenBSD/amd64 x86_64-*-openbsd*
4700 OpenBSD/alpha alpha*-*-openbsd*
4701 OpenBSD/sparc sparc-*-openbsd*
4702 OpenBSD/sparc64 sparc64-*-openbsd*
4704 * New debugging protocols
4706 M32R with SDI protocol m32r-*-elf*
4708 * "set prompt-escape-char" command deleted.
4710 The command "set prompt-escape-char" has been deleted. This command,
4711 and its very obscure effet on GDB's prompt, was never documented,
4712 tested, nor mentioned in the NEWS file.
4714 * OBSOLETE configurations and files
4716 Configurations that have been declared obsolete in this release have
4717 been commented out. Unless there is activity to revive these
4718 configurations, the next release of GDB will have their sources
4719 permanently REMOVED.
4721 Sun 3, running SunOS 3 m68*-*-sunos3*
4722 Sun 3, running SunOS 4 m68*-*-sunos4*
4723 Sun 2, running SunOS 3 m68000-*-sunos3*
4724 Sun 2, running SunOS 4 m68000-*-sunos4*
4725 Motorola 680x0 running LynxOS m68*-*-lynxos*
4726 AT&T 3b1/Unix pc m68*-att-*
4727 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4728 decstation mips-dec-* mips-little-*
4729 riscos mips-*-riscos* mips-*-sysv*
4730 sonymips mips-sony-*
4731 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4733 * REMOVED configurations and files
4735 SGI Irix-4.x mips-sgi-irix4 or iris4
4736 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4737 Z8000 simulator z8k-zilog-none or z8ksim
4738 Matsushita MN10200 w/simulator mn10200-*-*
4739 H8/500 simulator h8500-hitachi-hms or h8500hms
4740 HP/PA running BSD hppa*-*-bsd*
4741 HP/PA running OSF/1 hppa*-*-osf*
4742 HP/PA Pro target hppa*-*-pro*
4743 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4744 386BSD i[3456]86-*-bsd*
4745 Sequent family i[3456]86-sequent-sysv4*
4746 i[3456]86-sequent-sysv*
4747 i[3456]86-sequent-bsd*
4748 SPARC running LynxOS sparc-*-lynxos*
4749 SPARC running SunOS 4 sparc-*-sunos4*
4750 Tsqware Sparclet sparclet-*-*
4751 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4753 *** Changes in GDB 6.0:
4757 Support for debugging the Objective-C programming language has been
4758 integrated into GDB.
4760 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4762 DWARF 2's Call Frame Information makes available compiler generated
4763 information that more exactly describes the program's run-time stack.
4764 By using this information, GDB is able to provide more robust stack
4767 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4768 have been updated to use a new backtrace mechanism which includes
4769 DWARF 2 CFI support.
4773 GDB's remote protocol has been extended to include support for hosted
4774 file I/O (where the remote target uses GDB's file system). See GDB's
4775 remote protocol documentation for details.
4777 * All targets using the new architecture framework.
4779 All of GDB's targets have been updated to use the new internal
4780 architecture framework. The way is now open for future GDB releases
4781 to include cross-architecture native debugging support (i386 on amd64,
4784 * GNU/Linux's Thread Local Storage (TLS)
4786 GDB now includes support for for the GNU/Linux implementation of
4787 per-thread variables.
4789 * GNU/Linux's Native POSIX Thread Library (NPTL)
4791 GDB's thread code has been updated to work with either the new
4792 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4794 * Separate debug info.
4796 GDB, in conjunction with BINUTILS, now supports a mechanism for
4797 automatically loading debug information from a separate file. Instead
4798 of shipping full debug and non-debug versions of system libraries,
4799 system integrators can now instead ship just the stripped libraries
4800 and optional debug files.
4802 * DWARF 2 Location Expressions
4804 DWARF 2 Location Expressions allow the compiler to more completely
4805 describe the location of variables (even in optimized code) to the
4808 GDB now includes preliminary support for location expressions (support
4809 for DW_OP_piece is still missing).
4813 A number of long standing bugs that caused GDB to die while starting a
4814 Java application have been fixed. GDB's Java support is now
4815 considered "useable".
4817 * GNU/Linux support for fork, vfork, and exec.
4819 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4820 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4823 * GDB supports logging output to a file
4825 There are two new commands, "set logging" and "show logging", which can be
4826 used to capture GDB's output to a file.
4828 * The meaning of "detach" has changed for gdbserver
4830 The "detach" command will now resume the application, as documented. To
4831 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4834 * d10v, m68hc11 `regs' command deprecated
4836 The `info registers' command has been updated so that it displays the
4837 registers using a format identical to the old `regs' command.
4841 A new command, "maint set profile on/off", has been added. This command can
4842 be used to enable or disable profiling while running GDB, to profile a
4843 session or a set of commands. In addition there is a new configure switch,
4844 "--enable-profiling", which will cause GDB to be compiled with profiling
4845 data, for more informative profiling results.
4847 * Default MI syntax changed to "mi2".
4849 The default MI (machine interface) syntax, enabled by the command line
4850 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4851 "mi1", can be enabled by specifying the option "-i=mi1".
4853 Support for the original "mi0" syntax (included in GDB 5.0) has been
4856 Fix for gdb/192: removed extraneous space when displaying frame level.
4857 Fix for gdb/672: update changelist is now output in mi list format.
4858 Fix for gdb/702: a -var-assign that updates the value now shows up
4859 in a subsequent -var-update.
4861 * New native configurations.
4863 FreeBSD/amd64 x86_64-*-freebsd*
4865 * Multi-arched targets.
4867 HP/PA HPUX11 hppa*-*-hpux*
4868 Renesas M32R/D w/simulator m32r-*-elf*
4870 * OBSOLETE configurations and files
4872 Configurations that have been declared obsolete in this release have
4873 been commented out. Unless there is activity to revive these
4874 configurations, the next release of GDB will have their sources
4875 permanently REMOVED.
4877 Z8000 simulator z8k-zilog-none or z8ksim
4878 Matsushita MN10200 w/simulator mn10200-*-*
4879 H8/500 simulator h8500-hitachi-hms or h8500hms
4880 HP/PA running BSD hppa*-*-bsd*
4881 HP/PA running OSF/1 hppa*-*-osf*
4882 HP/PA Pro target hppa*-*-pro*
4883 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4884 Sequent family i[3456]86-sequent-sysv4*
4885 i[3456]86-sequent-sysv*
4886 i[3456]86-sequent-bsd*
4887 Tsqware Sparclet sparclet-*-*
4888 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4890 * REMOVED configurations and files
4893 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4894 IBM AIX PS/2 i[3456]86-*-aix
4895 i386 running Mach 3.0 i[3456]86-*-mach3*
4896 i386 running Mach i[3456]86-*-mach*
4897 i386 running OSF/1 i[3456]86-*osf1mk*
4898 HP/Apollo 68k Family m68*-apollo*-sysv*,
4900 m68*-hp-bsd*, m68*-hp-hpux*
4901 Argonaut Risc Chip (ARC) arc-*-*
4902 Mitsubishi D30V d30v-*-*
4903 Fujitsu FR30 fr30-*-elf*
4904 OS/9000 i[34]86-*-os9k
4905 I960 with MON960 i960-*-coff
4907 * MIPS $fp behavior changed
4909 The convenience variable $fp, for the MIPS, now consistently returns
4910 the address of the current frame's base. Previously, depending on the
4911 context, $fp could refer to either $sp or the current frame's base
4912 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4913 The GNU Source-Level Debugger''.
4915 *** Changes in GDB 5.3:
4917 * GNU/Linux shared library multi-threaded performance improved.
4919 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4920 `/proc', in preference to `ptrace' for memory reads. This may result
4921 in an improvement in the start-up time of multi-threaded, shared
4922 library applications when run under GDB. One GDB user writes: ``loads
4923 shared libs like mad''.
4925 * ``gdbserver'' now supports multi-threaded applications on some targets
4927 Support for debugging multi-threaded applications which use
4928 the GNU/Linux LinuxThreads package has been added for
4929 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4930 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4932 * GDB now supports C/C++ preprocessor macros.
4934 GDB now expands preprocessor macro invocations in C/C++ expressions,
4935 and provides various commands for showing macro definitions and how
4938 The new command `macro expand EXPRESSION' expands any macro
4939 invocations in expression, and shows the result.
4941 The new command `show macro MACRO-NAME' shows the definition of the
4942 macro named MACRO-NAME, and where it was defined.
4944 Most compilers don't include information about macros in the debugging
4945 information by default. In GCC 3.1, for example, you need to compile
4946 your program with the options `-gdwarf-2 -g3'. If the macro
4947 information is present in the executable, GDB will read it.
4949 * Multi-arched targets.
4951 DEC Alpha (partial) alpha*-*-*
4952 DEC VAX (partial) vax-*-*
4954 National Semiconductor NS32000 (partial) ns32k-*-*
4955 Motorola 68000 (partial) m68k-*-*
4956 Motorola MCORE mcore-*-*
4960 Fujitsu FRV architecture added by Red Hat frv*-*-*
4963 * New native configurations
4965 Alpha NetBSD alpha*-*-netbsd*
4966 SH NetBSD sh*-*-netbsdelf*
4967 MIPS NetBSD mips*-*-netbsd*
4968 UltraSPARC NetBSD sparc64-*-netbsd*
4970 * OBSOLETE configurations and files
4972 Configurations that have been declared obsolete in this release have
4973 been commented out. Unless there is activity to revive these
4974 configurations, the next release of GDB will have their sources
4975 permanently REMOVED.
4977 Mitsubishi D30V d30v-*-*
4978 OS/9000 i[34]86-*-os9k
4979 IBM AIX PS/2 i[3456]86-*-aix
4980 Fujitsu FR30 fr30-*-elf*
4981 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4982 Argonaut Risc Chip (ARC) arc-*-*
4983 i386 running Mach 3.0 i[3456]86-*-mach3*
4984 i386 running Mach i[3456]86-*-mach*
4985 i386 running OSF/1 i[3456]86-*osf1mk*
4986 HP/Apollo 68k Family m68*-apollo*-sysv*,
4988 m68*-hp-bsd*, m68*-hp-hpux*
4989 I960 with MON960 i960-*-coff
4991 * OBSOLETE languages
4993 CHILL, a Pascal like language used by telecommunications companies.
4995 * REMOVED configurations and files
4997 AMD 29k family via UDI a29k-amd-udi, udi29k
4998 A29K VxWorks a29k-*-vxworks
4999 AMD 29000 embedded, using EBMON a29k-none-none
5000 AMD 29000 embedded with COFF a29k-none-coff
5001 AMD 29000 embedded with a.out a29k-none-aout
5003 testsuite/gdb.hp/gdb.threads-hp/ directory
5005 * New command "set max-user-call-depth <nnn>"
5007 This command allows the user to limit the call depth of user-defined
5008 commands. The default is 1024.
5010 * Changes in FreeBSD/i386 native debugging.
5012 Support for the "generate-core-file" has been added.
5014 * New commands "dump", "append", and "restore".
5016 These commands allow data to be copied from target memory
5017 to a bfd-format or binary file (dump and append), and back
5018 from a file into memory (restore).
5020 * Improved "next/step" support on multi-processor Alpha Tru64.
5022 The previous single-step mechanism could cause unpredictable problems,
5023 including the random appearance of SIGSEGV or SIGTRAP signals. The use
5024 of a software single-step mechanism prevents this.
5026 *** Changes in GDB 5.2.1:
5034 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
5035 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
5036 Fix, by Joel Brobecker imported from mainline.
5038 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
5039 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
5040 Fix, by Fred Fish, imported from mainline.
5042 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
5043 Surprisingly enough, it works now.
5044 By Michal Ludvig, imported from mainline.
5046 i386 hardware watchpoint support:
5047 avoid misses on second run for some targets.
5048 By Pierre Muller, imported from mainline.
5050 *** Changes in GDB 5.2:
5052 * New command "set trust-readonly-sections on[off]".
5054 This command is a hint that tells gdb that read-only sections
5055 really are read-only (ie. that their contents will not change).
5056 In this mode, gdb will go to the object file rather than the
5057 target to read memory from read-only sections (such as ".text").
5058 This can be a significant performance improvement on some
5059 (notably embedded) targets.
5061 * New command "generate-core-file" (or "gcore").
5063 This new gdb command allows the user to drop a core file of the child
5064 process state at any time. So far it's been implemented only for
5065 GNU/Linux and Solaris, but should be relatively easily ported to other
5066 hosts. Argument is core file name (defaults to core.<pid>).
5068 * New command line option
5070 GDB now accepts --pid or -p followed by a process id.
5072 * Change in command line behavior -- corefiles vs. process ids.
5074 There is a subtle behavior in the way in which GDB handles
5075 command line arguments. The first non-flag argument is always
5076 a program to debug, but the second non-flag argument may either
5077 be a corefile or a process id. Previously, GDB would attempt to
5078 open the second argument as a corefile, and if that failed, would
5079 issue a superfluous error message and then attempt to attach it as
5080 a process. Now, if the second argument begins with a non-digit,
5081 it will be treated as a corefile. If it begins with a digit,
5082 GDB will attempt to attach it as a process, and if no such process
5083 is found, will then attempt to open it as a corefile.
5085 * Changes in ARM configurations.
5087 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
5088 configuration is fully multi-arch.
5090 * New native configurations
5092 ARM NetBSD arm*-*-netbsd*
5093 x86 OpenBSD i[3456]86-*-openbsd*
5094 AMD x86-64 running GNU/Linux x86_64-*-linux-*
5095 Sparc64 running FreeBSD sparc64-*-freebsd*
5099 Sanyo XStormy16 xstormy16-elf
5101 * OBSOLETE configurations and files
5103 Configurations that have been declared obsolete in this release have
5104 been commented out. Unless there is activity to revive these
5105 configurations, the next release of GDB will have their sources
5106 permanently REMOVED.
5108 AMD 29k family via UDI a29k-amd-udi, udi29k
5109 A29K VxWorks a29k-*-vxworks
5110 AMD 29000 embedded, using EBMON a29k-none-none
5111 AMD 29000 embedded with COFF a29k-none-coff
5112 AMD 29000 embedded with a.out a29k-none-aout
5114 testsuite/gdb.hp/gdb.threads-hp/ directory
5116 * REMOVED configurations and files
5118 TI TMS320C80 tic80-*-*
5120 PowerPC Solaris powerpcle-*-solaris*
5121 PowerPC Windows NT powerpcle-*-cygwin32
5122 PowerPC Netware powerpc-*-netware*
5123 Harris/CXUX m88k m88*-harris-cxux*
5124 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5125 ns32k-utek-sysv* ns32k-utek-*
5126 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5127 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5128 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5129 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5130 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
5132 * Changes to command line processing
5134 The new `--args' feature can be used to specify command-line arguments
5135 for the inferior from gdb's command line.
5137 * Changes to key bindings
5139 There is a new `operate-and-get-next' function bound to `C-o'.
5141 *** Changes in GDB 5.1.1
5143 Fix compile problem on DJGPP.
5145 Fix a problem with floating-point registers on the i386 being
5148 Fix to stop GDB crashing on .debug_str debug info.
5150 Numerous documentation fixes.
5152 Numerous testsuite fixes.
5154 *** Changes in GDB 5.1:
5156 * New native configurations
5158 Alpha FreeBSD alpha*-*-freebsd*
5159 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
5160 MIPS GNU/Linux mips*-*-linux*
5161 MIPS SGI Irix 6.x mips*-sgi-irix6*
5162 ia64 AIX ia64-*-aix*
5163 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
5167 Motorola 68HC11 and 68HC12 m68hc11-elf
5169 UltraSparc running GNU/Linux sparc64-*-linux*
5171 * OBSOLETE configurations and files
5173 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
5174 Harris/CXUX m88k m88*-harris-cxux*
5175 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5176 ns32k-utek-sysv* ns32k-utek-*
5177 TI TMS320C80 tic80-*-*
5179 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5180 PowerPC Solaris powerpcle-*-solaris*
5181 PowerPC Windows NT powerpcle-*-cygwin32
5182 PowerPC Netware powerpc-*-netware*
5183 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5184 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5185 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5186 Apple Macintosh (MPW) host N/A
5188 stuff.c (Program to stuff files into a specially prepared space in kdb)
5189 kdb-start.c (Main loop for the standalone kernel debugger)
5191 Configurations that have been declared obsolete in this release have
5192 been commented out. Unless there is activity to revive these
5193 configurations, the next release of GDB will have their sources
5194 permanently REMOVED.
5196 * REMOVED configurations and files
5198 Altos 3068 m68*-altos-*
5199 Convex c1-*-*, c2-*-*
5201 ARM RISCix arm-*-* (as host)
5205 * GDB has been converted to ISO C.
5207 GDB's source code has been converted to ISO C. In particular, the
5208 sources are fully protoized, and rely on standard headers being
5213 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
5215 * The MI enabled by default.
5217 The new machine oriented interface (MI) introduced in GDB 5.0 has been
5218 revised and enabled by default. Packages which use GDB as a debugging
5219 engine behind a UI or another front end are encouraged to switch to
5220 using the GDB/MI interface, instead of the old annotations interface
5221 which is now deprecated.
5223 * Support for debugging Pascal programs.
5225 GDB now includes support for debugging Pascal programs. The following
5226 main features are supported:
5228 - Pascal-specific data types such as sets;
5230 - automatic recognition of Pascal sources based on file-name
5233 - Pascal-style display of data types, variables, and functions;
5235 - a Pascal expression parser.
5237 However, some important features are not yet supported.
5239 - Pascal string operations are not supported at all;
5241 - there are some problems with boolean types;
5243 - Pascal type hexadecimal constants are not supported
5244 because they conflict with the internal variables format;
5246 - support for Pascal objects and classes is not full yet;
5248 - unlike Pascal, GDB is case-sensitive for symbol names.
5250 * Changes in completion.
5252 Commands such as `shell', `run' and `set args', which pass arguments
5253 to inferior programs, now complete on file names, similar to what
5254 users expect at the shell prompt.
5256 Commands which accept locations, such as `disassemble', `print',
5257 `breakpoint', `until', etc. now complete on filenames as well as
5258 program symbols. Thus, if you type "break foob TAB", and the source
5259 files linked into the programs include `foobar.c', that file name will
5260 be one of the candidates for completion. However, file names are not
5261 considered for completion after you typed a colon that delimits a file
5262 name from a name of a function in that file, as in "break foo.c:bar".
5264 `set demangle-style' completes on available demangling styles.
5266 * New platform-independent commands:
5268 It is now possible to define a post-hook for a command as well as a
5269 hook that runs before the command. For more details, see the
5270 documentation of `hookpost' in the GDB manual.
5272 * Changes in GNU/Linux native debugging.
5274 Support for debugging multi-threaded programs has been completely
5275 revised for all platforms except m68k and sparc. You can now debug as
5276 many threads as your system allows you to have.
5278 Attach/detach is supported for multi-threaded programs.
5280 Support for SSE registers was added for x86. This doesn't work for
5281 multi-threaded programs though.
5283 * Changes in MIPS configurations.
5285 Multi-arch support is enabled for all MIPS configurations.
5287 GDB can now be built as native debugger on SGI Irix 6.x systems for
5288 debugging n32 executables. (Debugging 64-bit executables is not yet
5291 * Unified support for hardware watchpoints in all x86 configurations.
5293 Most (if not all) native x86 configurations support hardware-assisted
5294 breakpoints and watchpoints in a unified manner. This support
5295 implements debug register sharing between watchpoints, which allows to
5296 put a virtually infinite number of watchpoints on the same address,
5297 and also supports watching regions up to 16 bytes with several debug
5300 The new maintenance command `maintenance show-debug-regs' toggles
5301 debugging print-outs in functions that insert, remove, and test
5302 watchpoints and hardware breakpoints.
5304 * Changes in the DJGPP native configuration.
5306 New command ``info dos sysinfo'' displays assorted information about
5307 the CPU, OS, memory, and DPMI server.
5309 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
5310 display information about segment descriptors stored in GDT, LDT, and
5313 New commands ``info dos pde'' and ``info dos pte'' display entries
5314 from Page Directory and Page Tables (for now works with CWSDPMI only).
5315 New command ``info dos address-pte'' displays the Page Table entry for
5316 a given linear address.
5318 GDB can now pass command lines longer than 126 characters to the
5319 program being debugged (requires an update to the libdbg.a library
5320 which is part of the DJGPP development kit).
5322 DWARF2 debug info is now supported.
5324 It is now possible to `step' and `next' through calls to `longjmp'.
5326 * Changes in documentation.
5328 All GDB documentation was converted to GFDL, the GNU Free
5329 Documentation License.
5331 Tracepoints-related commands are now fully documented in the GDB
5334 TUI, the Text-mode User Interface, is now documented in the manual.
5336 Tracepoints-related commands are now fully documented in the GDB
5339 The "GDB Internals" manual now has an index. It also includes
5340 documentation of `ui_out' functions, GDB coding standards, x86
5341 hardware watchpoints, and memory region attributes.
5343 * GDB's version number moved to ``version.in''
5345 The Makefile variable VERSION has been replaced by the file
5346 ``version.in''. People creating GDB distributions should update the
5347 contents of this file.
5351 GUD support is now a standard part of the EMACS distribution.
5353 *** Changes in GDB 5.0:
5355 * Improved support for debugging FP programs on x86 targets
5357 Unified and much-improved support for debugging floating-point
5358 programs on all x86 targets. In particular, ``info float'' now
5359 displays the FP registers in the same format on all x86 targets, with
5360 greater level of detail.
5362 * Improvements and bugfixes in hardware-assisted watchpoints
5364 It is now possible to watch array elements, struct members, and
5365 bitfields with hardware-assisted watchpoints. Data-read watchpoints
5366 on x86 targets no longer erroneously trigger when the address is
5369 * Improvements in the native DJGPP version of GDB
5371 The distribution now includes all the scripts and auxiliary files
5372 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5373 machines ``out of the box''.
5375 The DJGPP version can now debug programs that use signals. It is
5376 possible to catch signals that happened in the debuggee, deliver
5377 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5378 would kill the program being debugged.) Programs that hook hardware
5379 interrupts (keyboard, timer, etc.) can also be debugged.
5381 It is now possible to debug DJGPP programs that redirect their
5382 standard handles or switch them to raw (as opposed to cooked) mode, or
5383 even close them. The command ``run < foo > bar'' works as expected,
5384 and ``info terminal'' reports useful information about the debuggee's
5385 terminal, including raw/cooked mode, redirection, etc.
5387 The DJGPP version now uses termios functions for console I/O, which
5388 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5391 DOS-style file names with drive letters are now fully supported by
5394 It is now possible to debug DJGPP programs that switch their working
5395 directory. It is also possible to rerun the debuggee any number of
5396 times without restarting GDB; thus, you can use the same setup,
5397 breakpoints, etc. for many debugging sessions.
5399 * New native configurations
5401 ARM GNU/Linux arm*-*-linux*
5402 PowerPC GNU/Linux powerpc-*-linux*
5406 Motorola MCore mcore-*-*
5407 x86 VxWorks i[3456]86-*-vxworks*
5408 PowerPC VxWorks powerpc-*-vxworks*
5409 TI TMS320C80 tic80-*-*
5411 * OBSOLETE configurations
5413 Altos 3068 m68*-altos-*
5414 Convex c1-*-*, c2-*-*
5416 ARM RISCix arm-*-* (as host)
5419 Configurations that have been declared obsolete will be commented out,
5420 but the code will be left in place. If there is no activity to revive
5421 these configurations before the next release of GDB, the sources will
5422 be permanently REMOVED.
5424 * Gould support removed
5426 Support for the Gould PowerNode and NP1 has been removed.
5428 * New features for SVR4
5430 On SVR4 native platforms (such as Solaris), if you attach to a process
5431 without first loading a symbol file, GDB will now attempt to locate and
5432 load symbols from the running process's executable file.
5434 * Many C++ enhancements
5436 C++ support has been greatly improved. Overload resolution now works properly
5437 in almost all cases. RTTI support is on the way.
5439 * Remote targets can connect to a sub-program
5441 A popen(3) style serial-device has been added. This device starts a
5442 sub-process (such as a stand-alone simulator) and then communicates
5443 with that. The sub-program to run is specified using the syntax
5444 ``|<program> <args>'' vis:
5446 (gdb) set remotedebug 1
5447 (gdb) target extended-remote |mn10300-elf-sim program-args
5449 * MIPS 64 remote protocol
5451 A long standing bug in the mips64 remote protocol where by GDB
5452 expected certain 32 bit registers (ex SR) to be transfered as 32
5453 instead of 64 bits has been fixed.
5455 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5456 added to provide backward compatibility with older versions of GDB.
5458 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5460 The command ``set remotebinarydownload'' command has been replaced by
5461 ``set remote X-packet''. Other commands in ``set remote'' family
5462 include ``set remote P-packet''.
5464 * Breakpoint commands accept ranges.
5466 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5467 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5468 ``tracepoint passcount'' also accepts a range of tracepoints.
5470 * ``apropos'' command added.
5472 The ``apropos'' command searches through command names and
5473 documentation strings, printing out matches, making it much easier to
5474 try to find a command that does what you are looking for.
5478 A new machine oriented interface (MI) has been added to GDB. This
5479 interface is designed for debug environments running GDB as a separate
5480 process. This is part of the long term libGDB project. See the
5481 "GDB/MI" chapter of the GDB manual for further information. It can be
5482 enabled by configuring with:
5484 .../configure --enable-gdbmi
5486 *** Changes in GDB-4.18:
5488 * New native configurations
5490 HP-UX 10.20 hppa*-*-hpux10.20
5491 HP-UX 11.x hppa*-*-hpux11.0*
5492 M68K GNU/Linux m68*-*-linux*
5496 Fujitsu FR30 fr30-*-elf*
5497 Intel StrongARM strongarm-*-*
5498 Mitsubishi D30V d30v-*-*
5500 * OBSOLETE configurations
5502 Gould PowerNode, NP1 np1-*-*, pn-*-*
5504 Configurations that have been declared obsolete will be commented out,
5505 but the code will be left in place. If there is no activity to revive
5506 these configurations before the next release of GDB, the sources will
5507 be permanently REMOVED.
5511 As a compatibility experiment, GDB's source files buildsym.h and
5512 buildsym.c have been converted to pure standard C, no longer
5513 containing any K&R compatibility code. We believe that all systems in
5514 use today either come with a standard C compiler, or have a GCC port
5515 available. If this is not true, please report the affected
5516 configuration to bug-gdb@gnu.org immediately. See the README file for
5517 information about getting a standard C compiler if you don't have one
5522 GDB now uses readline 2.2.
5524 * set extension-language
5526 You can now control the mapping between filename extensions and source
5527 languages by using the `set extension-language' command. For instance,
5528 you can ask GDB to treat .c files as C++ by saying
5529 set extension-language .c c++
5530 The command `info extensions' lists all of the recognized extensions
5531 and their associated languages.
5533 * Setting processor type for PowerPC and RS/6000
5535 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5536 you can use the `set processor' command to specify what variant of the
5537 PowerPC family you are debugging. The command
5541 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5542 following PowerPC and RS6000 variants:
5544 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5545 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5547 403GC IBM PowerPC 403GC
5548 505 Motorola PowerPC 505
5549 860 Motorola PowerPC 860 or 850
5550 601 Motorola PowerPC 601
5551 602 Motorola PowerPC 602
5552 603 Motorola/IBM PowerPC 603 or 603e
5553 604 Motorola PowerPC 604 or 604e
5554 750 Motorola/IBM PowerPC 750 or 750
5556 At the moment, this command just tells GDB what to name the
5557 special-purpose processor registers. Since almost all the affected
5558 registers are inaccessible to user-level programs, this command is
5559 only useful for remote debugging in its present form.
5563 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5564 more extensive support for HP-UX. Added features include shared
5565 library support, kernel threads and hardware watchpoints for 11.00,
5566 support for HP's ANSI C and C++ compilers, and a compatibility mode
5567 for xdb and dbx commands.
5571 HP's donation includes the new concept of catchpoints, which is a
5572 generalization of the old catch command. On HP-UX, it is now possible
5573 to catch exec, fork, and vfork, as well as library loading.
5575 This means that the existing catch command has changed; its first
5576 argument now specifies the type of catch to be set up. See the
5577 output of "help catch" for a list of catchpoint types.
5579 * Debugging across forks
5581 On HP-UX, you can choose which process to debug when a fork() happens
5586 HP has donated a curses-based terminal user interface (TUI). To get
5587 it, build with --enable-tui. Although this can be enabled for any
5588 configuration, at present it only works for native HP debugging.
5590 * GDB remote protocol additions
5592 A new protocol packet 'X' that writes binary data is now available.
5593 Default behavior is to try 'X', then drop back to 'M' if the stub
5594 fails to respond. The settable variable `remotebinarydownload'
5595 allows explicit control over the use of 'X'.
5597 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5598 full 64-bit address. The command
5600 set remoteaddresssize 32
5602 can be used to revert to the old behaviour. For existing remote stubs
5603 the change should not be noticed, as the additional address information
5606 In order to assist in debugging stubs, you may use the maintenance
5607 command `packet' to send any text string to the stub. For instance,
5609 maint packet heythere
5611 sends the packet "$heythere#<checksum>". Note that it is very easy to
5612 disrupt a debugging session by sending the wrong packet at the wrong
5615 The compare-sections command allows you to compare section data on the
5616 target to what is in the executable file without uploading or
5617 downloading, by comparing CRC checksums.
5619 * Tracing can collect general expressions
5621 You may now collect general expressions at tracepoints. This requires
5622 further additions to the target-side stub; see tracepoint.c and
5623 doc/agentexpr.texi for further details.
5625 * mask-address variable for Mips
5627 For Mips targets, you may control the zeroing of the upper 32 bits of
5628 a 64-bit address by entering `set mask-address on'. This is mainly
5629 of interest to users of embedded R4xxx and R5xxx processors.
5631 * Higher serial baud rates
5633 GDB's serial code now allows you to specify baud rates 57600, 115200,
5634 230400, and 460800 baud. (Note that your host system may not be able
5635 to achieve all of these rates.)
5639 The i960 configuration now includes an initial implementation of a
5640 builtin simulator, contributed by Jim Wilson.
5643 *** Changes in GDB-4.17:
5645 * New native configurations
5647 Alpha GNU/Linux alpha*-*-linux*
5648 Unixware 2.x i[3456]86-unixware2*
5649 Irix 6.x mips*-sgi-irix6*
5650 PowerPC GNU/Linux powerpc-*-linux*
5651 PowerPC Solaris powerpcle-*-solaris*
5652 Sparc GNU/Linux sparc-*-linux*
5653 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5657 Argonaut Risc Chip (ARC) arc-*-*
5658 Hitachi H8/300S h8300*-*-*
5659 Matsushita MN10200 w/simulator mn10200-*-*
5660 Matsushita MN10300 w/simulator mn10300-*-*
5661 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5662 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5663 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5664 Mitsubishi D10V w/simulator d10v-*-*
5665 Mitsubishi M32R/D w/simulator m32r-*-elf*
5666 Tsqware Sparclet sparclet-*-*
5667 NEC V850 w/simulator v850-*-*
5669 * New debugging protocols
5671 ARM with RDI protocol arm*-*-*
5672 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5673 DDB and LSI variants of PMON protocol mips*-*-*
5674 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5675 PowerPC with SDS protocol powerpc{,le}-*-eabi
5676 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5680 All configurations can now understand and use the DWARF 2 debugging
5681 format. The choice is automatic, if the symbol file contains DWARF 2
5686 GDB now includes basic Java language support. This support is
5687 only useful with Java compilers that produce native machine code.
5689 * solib-absolute-prefix and solib-search-path
5691 For SunOS and SVR4 shared libraries, you may now set the prefix for
5692 loading absolute shared library symbol files, and the search path for
5693 locating non-absolute shared library symbol files.
5695 * Live range splitting
5697 GDB can now effectively debug code for which GCC has performed live
5698 range splitting as part of its optimization. See gdb/doc/LRS for
5699 more details on the expected format of the stabs information.
5703 GDB's support for the GNU Hurd, including thread debugging, has been
5704 updated to work with current versions of the Hurd.
5708 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5709 instruction set. ARM GDB automatically detects when Thumb
5710 instructions are in use, and adjusts disassembly and backtracing
5715 GDB's MIPS target configurations now handle the MIP16 16-bit
5720 GDB now includes support for overlays; if an executable has been
5721 linked such that multiple sections are based at the same address, GDB
5722 will decide which section to use for symbolic info. You can choose to
5723 control the decision manually, using overlay commands, or implement
5724 additional target-side support and use "overlay load-target" to bring
5725 in the overlay mapping. Do "help overlay" for more detail.
5729 The command "info symbol <address>" displays information about
5730 the symbol at the specified address.
5734 The standard remote protocol now includes an extension that allows
5735 asynchronous collection and display of trace data. This requires
5736 extensive support in the target-side debugging stub. Tracing mode
5737 includes a new interaction mode in GDB and new commands: see the
5738 file tracepoint.c for more details.
5742 Configurations for embedded MIPS now include a simulator contributed
5743 by Cygnus Solutions. The simulator supports the instruction sets
5744 of most MIPS variants.
5748 Sparc configurations may now include the ERC32 simulator contributed
5749 by the European Space Agency. The simulator is not built into
5750 Sparc targets by default; configure with --enable-sim to include it.
5754 For target configurations that may include multiple variants of a
5755 basic architecture (such as MIPS and SH), you may now set the
5756 architecture explicitly. "set arch" sets, "info arch" lists
5757 the possible architectures.
5759 *** Changes in GDB-4.16:
5761 * New native configurations
5763 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5764 M68K NetBSD m68k-*-netbsd*
5765 PowerPC AIX 4.x powerpc-*-aix*
5766 PowerPC MacOS powerpc-*-macos*
5767 PowerPC Windows NT powerpcle-*-cygwin32
5768 RS/6000 AIX 4.x rs6000-*-aix4*
5772 ARM with RDP protocol arm-*-*
5773 I960 with MON960 i960-*-coff
5774 MIPS VxWorks mips*-*-vxworks*
5775 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5776 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5778 Matra Sparclet sparclet-*-*
5782 The powerpc-eabi configuration now includes the PSIM simulator,
5783 contributed by Andrew Cagney, with assistance from Mike Meissner.
5784 PSIM is a very elaborate model of the PowerPC, including not only
5785 basic instruction set execution, but also details of execution unit
5786 performance and I/O hardware. See sim/ppc/README for more details.
5790 GDB now works with Solaris 2.5.
5792 * Windows 95/NT native
5794 GDB will now work as a native debugger on Windows 95 and Windows NT.
5795 To build it from source, you must use the "gnu-win32" environment,
5796 which uses a DLL to emulate enough of Unix to run the GNU tools.
5797 Further information, binaries, and sources are available at
5798 ftp.cygnus.com, under pub/gnu-win32.
5800 * dont-repeat command
5802 If a user-defined command includes the command `dont-repeat', then the
5803 command will not be repeated if the user just types return. This is
5804 useful if the command is time-consuming to run, so that accidental
5805 extra keystrokes don't run the same command many times.
5807 * Send break instead of ^C
5809 The standard remote protocol now includes an option to send a break
5810 rather than a ^C to the target in order to interrupt it. By default,
5811 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5813 * Remote protocol timeout
5815 The standard remote protocol includes a new variable `remotetimeout'
5816 that allows you to set the number of seconds before GDB gives up trying
5817 to read from the target. The default value is 2.
5819 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5821 By default GDB will automatically keep track of objects as they are
5822 loaded and unloaded by the dynamic linker. By using the command `set
5823 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5824 when shared library events occur, thus allowing you to set breakpoints
5825 in shared libraries which are explicitly loaded by the inferior.
5827 Note this feature does not work on hpux8. On hpux9 you must link
5828 /usr/lib/end.o into your program. This feature should work
5829 automatically on hpux10.
5831 * Irix 5.x hardware watchpoint support
5833 Irix 5 configurations now support the use of hardware watchpoints.
5835 * Mips protocol "SYN garbage limit"
5837 When debugging a Mips target using the `target mips' protocol, you
5838 may set the number of characters that GDB will ignore by setting
5839 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5840 every character. The default value is 1050.
5842 * Recording and replaying remote debug sessions
5844 If you set `remotelogfile' to the name of a file, gdb will write to it
5845 a recording of a remote debug session. This recording may then be
5846 replayed back to gdb using "gdbreplay". See gdbserver/README for
5847 details. This is useful when you have a problem with GDB while doing
5848 remote debugging; you can make a recording of the session and send it
5849 to someone else, who can then recreate the problem.
5851 * Speedups for remote debugging
5853 GDB includes speedups for downloading and stepping MIPS systems using
5854 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5855 and more efficient S-record downloading.
5857 * Memory use reductions and statistics collection
5859 GDB now uses less memory and reports statistics about memory usage.
5860 Try the `maint print statistics' command, for example.
5862 *** Changes in GDB-4.15:
5864 * Psymtabs for XCOFF
5866 The symbol reader for AIX GDB now uses partial symbol tables. This
5867 can greatly improve startup time, especially for large executables.
5869 * Remote targets use caching
5871 Remote targets now use a data cache to speed up communication with the
5872 remote side. The data cache could lead to incorrect results because
5873 it doesn't know about volatile variables, thus making it impossible to
5874 debug targets which use memory mapped I/O devices. `set remotecache
5875 off' turns the the data cache off.
5877 * Remote targets may have threads
5879 The standard remote protocol now includes support for multiple threads
5880 in the target system, using new protocol commands 'H' and 'T'. See
5881 gdb/remote.c for details.
5885 If GDB is configured with `--enable-netrom', then it will include
5886 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5887 acts as though it is a bank of ROM on the target board, but you can
5888 write into it over the network. GDB's support consists only of
5889 support for fast loading into the emulated ROM; to debug, you must use
5890 another protocol, such as standard remote protocol. The usual
5891 sequence is something like
5893 target nrom <netrom-hostname>
5895 target remote <netrom-hostname>:1235
5899 GDB now includes support for the Apple Macintosh, as a host only. It
5900 may be run as either an MPW tool or as a standalone application, and
5901 it can debug through the serial port. All the usual GDB commands are
5902 available, but to the target command, you must supply "serial" as the
5903 device type instead of "/dev/ttyXX". See mpw-README in the main
5904 directory for more information on how to build. The MPW configuration
5905 scripts */mpw-config.in support only a few targets, and only the
5906 mips-idt-ecoff target has been tested.
5910 GDB configuration now uses autoconf. This is not user-visible,
5911 but does simplify configuration and building.
5915 GDB now supports hpux10.
5917 *** Changes in GDB-4.14:
5919 * New native configurations
5921 x86 FreeBSD i[345]86-*-freebsd
5922 x86 NetBSD i[345]86-*-netbsd
5923 NS32k NetBSD ns32k-*-netbsd
5924 Sparc NetBSD sparc-*-netbsd
5928 A29K VxWorks a29k-*-vxworks
5929 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5930 CPU32 EST-300 emulator m68*-*-est*
5931 PowerPC ELF powerpc-*-elf
5934 * Alpha OSF/1 support for procfs
5936 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5937 possible to attach to running processes. As the mounting of the /proc
5938 filesystem is optional on the Alpha, GDB automatically determines
5939 the availability of /proc during startup. This can lead to problems
5940 if /proc is unmounted after GDB has been started.
5942 * Arguments to user-defined commands
5944 User commands may accept up to 10 arguments separated by whitespace.
5945 Arguments are accessed within the user command via $arg0..$arg9. A
5948 print $arg0 + $arg1 + $arg2
5950 To execute the command use:
5953 Defines the command "adder" which prints the sum of its three arguments.
5954 Note the arguments are text substitutions, so they may reference variables,
5955 use complex expressions, or even perform inferior function calls.
5957 * New `if' and `while' commands
5959 This makes it possible to write more sophisticated user-defined
5960 commands. Both commands take a single argument, which is the
5961 expression to evaluate, and must be followed by the commands to
5962 execute, one per line, if the expression is nonzero, the list being
5963 terminated by the word `end'. The `if' command list may include an
5964 `else' word, which causes the following commands to be executed only
5965 if the expression is zero.
5967 * Fortran source language mode
5969 GDB now includes partial support for Fortran 77. It will recognize
5970 Fortran programs and can evaluate a subset of Fortran expressions, but
5971 variables and functions may not be handled correctly. GDB will work
5972 with G77, but does not yet know much about symbols emitted by other
5975 * Better HPUX support
5977 Most debugging facilities now work on dynamic executables for HPPAs
5978 running hpux9 or later. You can attach to running dynamically linked
5979 processes, but by default the dynamic libraries will be read-only, so
5980 for instance you won't be able to put breakpoints in them. To change
5981 that behavior do the following before running the program:
5987 This will cause the libraries to be mapped private and read-write.
5988 To revert to the normal behavior, do this:
5994 You cannot set breakpoints or examine data in the library until after
5995 the library is loaded if the function/data symbols do not have
5998 GDB can now also read debug symbols produced by the HP C compiler on
5999 HPPAs (sorry, no C++, Fortran or 68k support).
6001 * Target byte order now dynamically selectable
6003 You can choose which byte order to use with a target system, via the
6004 commands "set endian big" and "set endian little", and you can see the
6005 current setting by using "show endian". You can also give the command
6006 "set endian auto", in which case GDB will use the byte order
6007 associated with the executable. Currently, only embedded MIPS
6008 configurations support dynamic selection of target byte order.
6010 * New DOS host serial code
6012 This version uses DPMI interrupts to handle buffered I/O, so you
6013 no longer need to run asynctsr when debugging boards connected to
6016 *** Changes in GDB-4.13:
6018 * New "complete" command
6020 This lists all the possible completions for the rest of the line, if it
6021 were to be given as a command itself. This is intended for use by emacs.
6023 * Trailing space optional in prompt
6025 "set prompt" no longer adds a space for you after the prompt you set. This
6026 allows you to set a prompt which ends in a space or one that does not.
6028 * Breakpoint hit counts
6030 "info break" now displays a count of the number of times the breakpoint
6031 has been hit. This is especially useful in conjunction with "ignore"; you
6032 can ignore a large number of breakpoint hits, look at the breakpoint info
6033 to see how many times the breakpoint was hit, then run again, ignoring one
6034 less than that number, and this will get you quickly to the last hit of
6037 * Ability to stop printing at NULL character
6039 "set print null-stop" will cause GDB to stop printing the characters of
6040 an array when the first NULL is encountered. This is useful when large
6041 arrays actually contain only short strings.
6043 * Shared library breakpoints
6045 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
6046 breakpoints in shared libraries before the executable is run.
6048 * Hardware watchpoints
6050 There is a new hardware breakpoint for the watch command for sparclite
6051 targets. See gdb/sparclite/hw_breakpoint.note.
6053 Hardware watchpoints are also now supported under GNU/Linux.
6057 Annotations have been added. These are for use with graphical interfaces,
6058 and are still experimental. Currently only gdba.el uses these.
6060 * Improved Irix 5 support
6062 GDB now works properly with Irix 5.2.
6064 * Improved HPPA support
6066 GDB now works properly with the latest GCC and GAS.
6068 * New native configurations
6070 Sequent PTX4 i[34]86-sequent-ptx4
6071 HPPA running OSF/1 hppa*-*-osf*
6072 Atari TT running SVR4 m68*-*-sysv4*
6073 RS/6000 LynxOS rs6000-*-lynxos*
6077 OS/9000 i[34]86-*-os9k
6078 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
6081 * Hitachi SH7000 and E7000-PC ICE support
6083 There is now support for communicating with the Hitachi E7000-PC ICE.
6084 This is available automatically when GDB is configured for the SH.
6088 As usual, a variety of small fixes and improvements, both generic
6089 and configuration-specific. See the ChangeLog for more detail.
6091 *** Changes in GDB-4.12:
6093 * Irix 5 is now supported
6097 GDB-4.12 on the HPPA has a number of changes which make it unable
6098 to debug the output from the currently released versions of GCC and
6099 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
6100 of GCC and GAS, versions of these tools designed to work with GDB-4.12
6101 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
6104 *** Changes in GDB-4.11:
6106 * User visible changes:
6110 The "set remotedebug" option is now consistent between the mips remote
6111 target, remote targets using the gdb-specific protocol, UDI (AMD's
6112 debug protocol for the 29k) and the 88k bug monitor. It is now an
6113 integer specifying a debug level (normally 0 or 1, but 2 means more
6114 debugging info for the mips target).
6116 * DEC Alpha native support
6118 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
6119 debug info, but GDB works fairly well with the DEC compiler and should
6120 work with a future GCC release. See the README file for a few
6121 Alpha-specific notes.
6123 * Preliminary thread implementation
6125 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
6127 * LynxOS native and target support for 386
6129 This release has been hosted on LynxOS 2.2, and also can be configured
6130 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
6133 * Improvements in C++ mangling/demangling.
6135 This release has much better g++ debugging, specifically in name
6136 mangling/demangling, virtual function calls, print virtual table,
6137 call methods, ...etc.
6139 *** Changes in GDB-4.10:
6141 * User visible changes:
6143 Remote debugging using the GDB-specific (`target remote') protocol now
6144 supports the `load' command. This is only useful if you have some
6145 other way of getting the stub to the target system, and you can put it
6146 somewhere in memory where it won't get clobbered by the download.
6148 Filename completion now works.
6150 When run under emacs mode, the "info line" command now causes the
6151 arrow to point to the line specified. Also, "info line" prints
6152 addresses in symbolic form (as well as hex).
6154 All vxworks based targets now support a user settable option, called
6155 vxworks-timeout. This option represents the number of seconds gdb
6156 should wait for responses to rpc's. You might want to use this if
6157 your vxworks target is, perhaps, a slow software simulator or happens
6158 to be on the far side of a thin network line.
6162 This release contains support for using a DEC alpha as a GDB host for
6163 cross debugging. Native alpha debugging is not supported yet.
6166 *** Changes in GDB-4.9:
6170 This is the first GDB release which is accompanied by a matching testsuite.
6171 The testsuite requires installation of dejagnu, which should be available
6172 via ftp from most sites that carry GNU software.
6176 'Cfront' style demangling has had its name changed to 'ARM' style, to
6177 emphasize that it was written from the specifications in the C++ Annotated
6178 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
6179 disclaimers, it still generated too much confusion with users attempting to
6180 use gdb with AT&T cfront.
6184 GDB now uses a standard remote interface to a simulator library.
6185 So far, the library contains simulators for the Zilog Z8001/2, the
6186 Hitachi H8/300, H8/500 and Super-H.
6188 * New targets supported
6190 H8/300 simulator h8300-hitachi-hms or h8300hms
6191 H8/500 simulator h8500-hitachi-hms or h8500hms
6192 SH simulator sh-hitachi-hms or sh
6193 Z8000 simulator z8k-zilog-none or z8ksim
6194 IDT MIPS board over serial line mips-idt-ecoff
6196 Cross-debugging to GO32 targets is supported. It requires a custom
6197 version of the i386-stub.c module which is integrated with the
6198 GO32 memory extender.
6200 * New remote protocols
6202 MIPS remote debugging protocol.
6204 * New source languages supported
6206 This version includes preliminary support for Chill, a Pascal like language
6207 used by telecommunications companies. Chill support is also being integrated
6208 into the GNU compiler, but we don't know when it will be publically available.
6211 *** Changes in GDB-4.8:
6213 * HP Precision Architecture supported
6215 GDB now supports HP PA-RISC machines running HPUX. A preliminary
6216 version of this support was available as a set of patches from the
6217 University of Utah. GDB does not support debugging of programs
6218 compiled with the HP compiler, because HP will not document their file
6219 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
6220 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
6222 Many problems in the preliminary version have been fixed.
6224 * Faster and better demangling
6226 We have improved template demangling and fixed numerous bugs in the GNU style
6227 demangler. It can now handle type modifiers such as `static' or `const'. Wide
6228 character types (wchar_t) are now supported. Demangling of each symbol is now
6229 only done once, and is cached when the symbol table for a file is read in.
6230 This results in a small increase in memory usage for C programs, a moderate
6231 increase in memory usage for C++ programs, and a fantastic speedup in
6234 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
6235 from the specifications in the Annotated Reference Manual, which AT&T's
6236 compiler does not actually implement.
6238 * G++ multiple inheritance compiler problem
6240 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
6241 inheritance lattices was reworked to properly discover ambiguities. We
6242 recently found an example which causes this new algorithm to fail in a
6243 very subtle way, producing bad debug information for those classes.
6244 The file 'gcc.patch' (in this directory) can be applied to gcc to
6245 circumvent the problem. A future GCC release will contain a complete
6248 The previous G++ debug info problem (mentioned below for the gdb-4.7
6249 release) is fixed in gcc version 2.3.2.
6251 * Improved configure script
6253 The `configure' script will now attempt to guess your system type if
6254 you don't supply a host system type. The old scheme of supplying a
6255 host system triplet is preferable over using this. All the magic is
6256 done in the new `config.guess' script. Examine it for details.
6258 We have also brought our configure script much more in line with the FSF's
6259 version. It now supports the --with-xxx options. In particular,
6260 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
6261 The resulting GDB will not be able to read arbitrary object file formats --
6262 only the format ``expected'' to be used on the configured target system.
6263 We hope to make this the default in a future release.
6265 * Documentation improvements
6267 There's new internal documentation on how to modify GDB, and how to
6268 produce clean changes to the code. We implore people to read it
6269 before submitting changes.
6271 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
6272 M4 macros. The new texinfo.tex is provided in this release. Pre-built
6273 `info' files are also provided. To build `info' files from scratch,
6274 you will need the latest `makeinfo' release, which will be available in
6275 a future texinfo-X.Y release.
6277 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
6278 We're not sure exactly which versions have this problem, but it has
6279 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
6280 or better. If that isn't possible, there is a patch in
6281 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
6282 around this problem.
6286 GDB now supports array constants that can be used in expressions typed in by
6287 the user. The syntax is `{element, element, ...}'. Ie: you can now type
6288 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
6291 The new directory `gdb/sparclite' contains a program that demonstrates
6292 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
6294 * New native hosts supported
6296 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
6297 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
6299 * New targets supported
6301 AMD 29k family via UDI a29k-amd-udi or udi29k
6303 * New file formats supported
6305 BFD now supports reading HP/PA-RISC executables (SOM file format?),
6306 HPUX core files, and SCO 3.2v2 core files.
6310 Attaching to processes now works again; thanks for the many bug reports.
6312 We have also stomped on a bunch of core dumps caused by
6313 printf_filtered("%s") problems.
6315 We eliminated a copyright problem on the rpc and ptrace header files
6316 for VxWorks, which was discovered at the last minute during the 4.7
6317 release. You should now be able to build a VxWorks GDB.
6319 You can now interrupt gdb while an attached process is running. This
6320 will cause the attached process to stop, and give control back to GDB.
6322 We fixed problems caused by using too many file descriptors
6323 for reading symbols from object files and libraries. This was
6324 especially a problem for programs that used many (~100) shared
6327 The `step' command now only enters a subroutine if there is line number
6328 information for the subroutine. Otherwise it acts like the `next'
6329 command. Previously, `step' would enter subroutines if there was
6330 any debugging information about the routine. This avoids problems
6331 when using `cc -g1' on MIPS machines.
6333 * Internal improvements
6335 GDB's internal interfaces have been improved to make it easier to support
6336 debugging of multiple languages in the future.
6338 GDB now uses a common structure for symbol information internally.
6339 Minimal symbols (derived from linkage symbols in object files), partial
6340 symbols (from a quick scan of debug information), and full symbols
6341 contain a common subset of information, making it easier to write
6342 shared code that handles any of them.
6344 * New command line options
6346 We now accept --silent as an alias for --quiet.
6350 The memory-mapped-malloc library is now licensed under the GNU Library
6351 General Public License.
6353 *** Changes in GDB-4.7:
6355 * Host/native/target split
6357 GDB has had some major internal surgery to untangle the support for
6358 hosts and remote targets. Now, when you configure GDB for a remote
6359 target, it will no longer load in all of the support for debugging
6360 local programs on the host. When fully completed and tested, this will
6361 ensure that arbitrary host/target combinations are possible.
6363 The primary conceptual shift is to separate the non-portable code in
6364 GDB into three categories. Host specific code is required any time GDB
6365 is compiled on that host, regardless of the target. Target specific
6366 code relates to the peculiarities of the target, but can be compiled on
6367 any host. Native specific code is everything else: it can only be
6368 built when the host and target are the same system. Child process
6369 handling and core file support are two common `native' examples.
6371 GDB's use of /proc for controlling Unix child processes is now cleaner.
6372 It has been split out into a single module under the `target_ops' vector,
6373 plus two native-dependent functions for each system that uses /proc.
6375 * New hosts supported
6377 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6378 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6379 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6381 * New targets supported
6383 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6384 68030 and CPU32 m68030-*-*, m68332-*-*
6386 * New native hosts supported
6388 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6389 (386bsd is not well tested yet)
6390 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6392 * New file formats supported
6394 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6395 supports reading of `a.out.adobe' object files, which are an a.out
6396 format extended with minimal information about multiple sections.
6400 `show copying' is the same as the old `info copying'.
6401 `show warranty' is the same as `info warrantee'.
6402 These were renamed for consistency. The old commands continue to work.
6404 `info handle' is a new alias for `info signals'.
6406 You can now define pre-command hooks, which attach arbitrary command
6407 scripts to any command. The commands in the hook will be executed
6408 prior to the user's command. You can also create a hook which will be
6409 executed whenever the program stops. See gdb.texinfo.
6413 We now deal with Cfront style name mangling, and can even extract type
6414 info from mangled symbols. GDB can automatically figure out which
6415 symbol mangling style your C++ compiler uses.
6417 Calling of methods and virtual functions has been improved as well.
6421 The crash that occured when debugging Sun Ansi-C compiled binaries is
6422 fixed. This was due to mishandling of the extra N_SO stabs output
6425 We also finally got Ultrix 4.2 running in house, and fixed core file
6426 support, with help from a dozen people on the net.
6428 John M. Farrell discovered that the reason that single-stepping was so
6429 slow on all of the Mips based platforms (primarily SGI and DEC) was
6430 that we were trying to demangle and lookup a symbol used for internal
6431 purposes on every instruction that was being stepped through. Changing
6432 the name of that symbol so that it couldn't be mistaken for a C++
6433 mangled symbol sped things up a great deal.
6435 Rich Pixley sped up symbol lookups in general by getting much smarter
6436 about when C++ symbol mangling is necessary. This should make symbol
6437 completion (TAB on the command line) much faster. It's not as fast as
6438 we'd like, but it's significantly faster than gdb-4.6.
6442 A new user controllable variable 'call_scratch_address' can
6443 specify the location of a scratch area to be used when GDB
6444 calls a function in the target. This is necessary because the
6445 usual method of putting the scratch area on the stack does not work
6446 in systems that have separate instruction and data spaces.
6448 We integrated changes to support the 29k UDI (Universal Debugger
6449 Interface), but discovered at the last minute that we didn't have all
6450 of the appropriate copyright paperwork. We are working with AMD to
6451 resolve this, and hope to have it available soon.
6455 We have sped up the remote serial line protocol, especially for targets
6456 with lots of registers. It now supports a new `expedited status' ('T')
6457 message which can be used in place of the existing 'S' status message.
6458 This allows the remote stub to send only the registers that GDB
6459 needs to make a quick decision about single-stepping or conditional
6460 breakpoints, eliminating the need to fetch the entire register set for
6461 each instruction being stepped through.
6463 The GDB remote serial protocol now implements a write-through cache for
6464 registers, only re-reading the registers if the target has run.
6466 There is also a new remote serial stub for SPARC processors. You can
6467 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6468 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6469 processor with a serial port.
6473 Configure.in files have become much easier to read and modify. A new
6474 `table driven' format makes it more obvious what configurations are
6475 supported, and what files each one uses.
6479 There is a new opcodes library which will eventually contain all of the
6480 disassembly routines and opcode tables. At present, it only contains
6481 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6482 disassembler (binutils/objdump) to share these routines.
6484 The libiberty library is now copylefted under the GNU Library General
6485 Public License. This allows more liberal use, and was done so libg++
6486 can use it. This makes no difference to GDB, since the Library License
6487 grants all the rights from the General Public License.
6491 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6492 reference to the stabs symbol info used by the debugger. It is (as far
6493 as we know) the only published document on this fascinating topic. We
6494 encourage you to read it, compare it to the stabs information on your
6495 system, and send improvements on the document in general (to
6496 bug-gdb@prep.ai.mit.edu).
6498 And, of course, many bugs have been fixed.
6501 *** Changes in GDB-4.6:
6503 * Better support for C++ function names
6505 GDB now accepts as input the "demangled form" of C++ overloaded function
6506 names and member function names, and can do command completion on such names
6507 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6508 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6509 Make use of command completion, it is your friend.
6511 GDB also now accepts a variety of C++ mangled symbol formats. They are
6512 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6513 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6514 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6515 for the list of formats.
6517 * G++ symbol mangling problem
6519 Recent versions of gcc have a bug in how they emit debugging information for
6520 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6521 directory) can be applied to gcc to fix the problem. Alternatively, if you
6522 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6523 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6524 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6527 * New 'maintenance' command
6529 All of the commands related to hacking GDB internals have been moved out of
6530 the main command set, and now live behind the 'maintenance' command. This
6531 can also be abbreviated as 'mt'. The following changes were made:
6533 dump-me -> maintenance dump-me
6534 info all-breakpoints -> maintenance info breakpoints
6535 printmsyms -> maintenance print msyms
6536 printobjfiles -> maintenance print objfiles
6537 printpsyms -> maintenance print psymbols
6538 printsyms -> maintenance print symbols
6540 The following commands are new:
6542 maintenance demangle Call internal GDB demangler routine to
6543 demangle a C++ link name and prints the result.
6544 maintenance print type Print a type chain for a given symbol
6546 * Change to .gdbinit file processing
6548 We now read the $HOME/.gdbinit file before processing the argv arguments
6549 (e.g. reading symbol files or core files). This allows global parameters to
6550 be set, which will apply during the symbol reading. The ./.gdbinit is still
6551 read after argv processing.
6553 * New hosts supported
6555 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6557 GNU/Linux support i386-unknown-linux or linux
6559 We are also including code to support the HP/PA running BSD and HPUX. This
6560 is almost guaranteed not to work, as we didn't have time to test or build it
6561 for this release. We are including it so that the more adventurous (or
6562 masochistic) of you can play with it. We also had major problems with the
6563 fact that the compiler that we got from HP doesn't support the -g option.
6566 * New targets supported
6568 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6570 * More smarts about finding #include files
6572 GDB now remembers the compilation directory for all include files, and for
6573 all files from which C is generated (like yacc and lex sources). This
6574 greatly improves GDB's ability to find yacc/lex sources, and include files,
6575 especially if you are debugging your program from a directory different from
6576 the one that contains your sources.
6578 We also fixed a bug which caused difficulty with listing and setting
6579 breakpoints in include files which contain C code. (In the past, you had to
6580 try twice in order to list an include file that you hadn't looked at before.)
6582 * Interesting infernals change
6584 GDB now deals with arbitrary numbers of sections, where the symbols for each
6585 section must be relocated relative to that section's landing place in the
6586 target's address space. This work was needed to support ELF with embedded
6587 stabs used by Solaris-2.0.
6589 * Bug fixes (of course!)
6591 There have been loads of fixes for the following things:
6592 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6593 i960, stabs, DOS(GO32), procfs, etc...
6595 See the ChangeLog for details.
6597 *** Changes in GDB-4.5:
6599 * New machines supported (host and target)
6601 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6603 SGI Irix-4.x mips-sgi-irix4 or iris4
6605 * New malloc package
6607 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6608 Mmalloc is capable of handling mutiple heaps of memory. It is also
6609 capable of saving a heap to a file, and then mapping it back in later.
6610 This can be used to greatly speedup the startup of GDB by using a
6611 pre-parsed symbol table which lives in a mmalloc managed heap. For
6612 more details, please read mmalloc/mmalloc.texi.
6616 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6617 'help info proc' for details.
6619 * MIPS ecoff symbol table format
6621 The code that reads MIPS symbol table format is now supported on all hosts.
6622 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6625 * File name changes for MS-DOS
6627 Many files in the config directories have been renamed to make it easier to
6628 support GDB on MS-DOSe systems (which have very restrictive file name
6629 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6630 environment) is close to working but has some remaining problems. Note
6631 that debugging of DOS programs is not supported, due to limitations
6632 in the ``operating system'', but it can be used to host cross-debugging.
6634 * Cross byte order fixes
6636 Many fixes have been made to support cross debugging of Sparc and MIPS
6637 targets from hosts whose byte order differs.
6639 * New -mapped and -readnow options
6641 If memory-mapped files are available on your system through the 'mmap'
6642 system call, you can use the -mapped option on the `file' or
6643 `symbol-file' commands to cause GDB to write the symbols from your
6644 program into a reusable file. If the program you are debugging is
6645 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6646 Future GDB debugging sessions will notice the presence of this file,
6647 and will quickly map in symbol information from it, rather than reading
6648 the symbol table from the executable program. Using the '-mapped'
6649 option in a GDB `file' or `symbol-file' command has the same effect as
6650 starting GDB with the '-mapped' command-line option.
6652 You can cause GDB to read the entire symbol table immediately by using
6653 the '-readnow' option with any of the commands that load symbol table
6654 information (or on the GDB command line). This makes the command
6655 slower, but makes future operations faster.
6657 The -mapped and -readnow options are typically combined in order to
6658 build a `fred.syms' file that contains complete symbol information.
6659 A simple GDB invocation to do nothing but build a `.syms' file for future
6662 gdb -batch -nx -mapped -readnow programname
6664 The `.syms' file is specific to the host machine on which GDB is run.
6665 It holds an exact image of GDB's internal symbol table. It cannot be
6666 shared across multiple host platforms.
6668 * longjmp() handling
6670 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6671 siglongjmp() without losing control. This feature has not yet been ported to
6672 all systems. It currently works on many 386 platforms, all MIPS-based
6673 platforms (SGI, DECstation, etc), and Sun3/4.
6677 Preliminary work has been put in to support the new Solaris OS from Sun. At
6678 this time, it can control and debug processes, but it is not capable of
6683 As always, many many bug fixes. The major areas were with g++, and mipsread.
6684 People using the MIPS-based platforms should experience fewer mysterious
6685 crashes and trashed symbol tables.
6687 *** Changes in GDB-4.4:
6689 * New machines supported (host and target)
6691 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6693 BSD Reno on Vax vax-dec-bsd
6694 Ultrix on Vax vax-dec-ultrix
6696 * New machines supported (target)
6698 AMD 29000 embedded, using EBMON a29k-none-none
6702 GDB continues to improve its handling of C++. `References' work better.
6703 The demangler has also been improved, and now deals with symbols mangled as
6704 per the Annotated C++ Reference Guide.
6706 GDB also now handles `stabs' symbol information embedded in MIPS
6707 `ecoff' symbol tables. Since the ecoff format was not easily
6708 extensible to handle new languages such as C++, this appeared to be a
6709 good way to put C++ debugging info into MIPS binaries. This option
6710 will be supported in the GNU C compiler, version 2, when it is
6713 * New features for SVR4
6715 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6716 shared libraries. Debugging dynamically linked programs should present
6717 only minor differences from debugging statically linked programs.
6719 The `info proc' command will print out information about any process
6720 on an SVR4 system (including the one you are debugging). At the moment,
6721 it prints the address mappings of the process.
6723 If you bring up GDB on another SVR4 system, please send mail to
6724 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6726 * Better dynamic linking support in SunOS
6728 Reading symbols from shared libraries which contain debugging symbols
6729 now works properly. However, there remain issues such as automatic
6730 skipping of `transfer vector' code during function calls, which
6731 make it harder to debug code in a shared library, than to debug the
6732 same code linked statically.
6736 GDB is now using the latest `getopt' routines from the FSF. This
6737 version accepts the -- prefix for options with long names. GDB will
6738 continue to accept the old forms (-option and +option) as well.
6739 Various single letter abbreviations for options have been explicity
6740 added to the option table so that they won't get overshadowed in the
6741 future by other options that begin with the same letter.
6745 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6746 Many assorted bugs have been handled. Many more remain to be handled.
6747 See the various ChangeLog files (primarily in gdb and bfd) for details.
6750 *** Changes in GDB-4.3:
6752 * New machines supported (host and target)
6754 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6755 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6756 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6758 * Almost SCO Unix support
6760 We had hoped to support:
6761 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6762 (except for core file support), but we discovered very late in the release
6763 that it has problems with process groups that render gdb unusable. Sorry
6764 about that. I encourage people to fix it and post the fixes.
6766 * Preliminary ELF and DWARF support
6768 GDB can read ELF object files on System V Release 4, and can handle
6769 debugging records for C, in DWARF format, in ELF files. This support
6770 is preliminary. If you bring up GDB on another SVR4 system, please
6771 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6776 GDB now uses the latest `readline' library. One user-visible change
6777 is that two tabs will list possible command completions, which previously
6778 required typing M-? (meta-question mark, or ESC ?).
6782 The `stepi' bug that many of you noticed has been squashed.
6783 Many bugs in C++ have been handled. Many more remain to be handled.
6784 See the various ChangeLog files (primarily in gdb and bfd) for details.
6786 * State of the MIPS world (in case you wondered):
6788 GDB can understand the symbol tables emitted by the compilers
6789 supplied by most vendors of MIPS-based machines, including DEC. These
6790 symbol tables are in a format that essentially nobody else uses.
6792 Some versions of gcc come with an assembler post-processor called
6793 mips-tfile. This program is required if you want to do source-level
6794 debugging of gcc-compiled programs. I believe FSF does not ship
6795 mips-tfile with gcc version 1, but it will eventually come with gcc
6798 Debugging of g++ output remains a problem. g++ version 1.xx does not
6799 really support it at all. (If you're lucky, you should be able to get
6800 line numbers and stack traces to work, but no parameters or local
6801 variables.) With some work it should be possible to improve the
6804 When gcc version 2 is released, you will have somewhat better luck.
6805 However, even then you will get confusing results for inheritance and
6808 We will eventually provide full debugging of g++ output on
6809 DECstations. This will probably involve some kind of stabs-in-ecoff
6810 encapulation, but the details have not been worked out yet.
6813 *** Changes in GDB-4.2:
6815 * Improved configuration
6817 Only one copy of `configure' exists now, and it is not self-modifying.
6818 Porting BFD is simpler.
6822 The `step' and `next' commands now only stop at the first instruction
6823 of a source line. This prevents the multiple stops that used to occur
6824 in switch statements, for-loops, etc. `Step' continues to stop if a
6825 function that has debugging information is called within the line.
6829 Lots of small bugs fixed. More remain.
6831 * New host supported (not target)
6833 Intel 386 PC clone running Mach i386-none-mach
6836 *** Changes in GDB-4.1:
6838 * Multiple source language support
6840 GDB now has internal scaffolding to handle several source languages.
6841 It determines the type of each source file from its filename extension,
6842 and will switch expression parsing and number formatting to match the
6843 language of the function in the currently selected stack frame.
6844 You can also specifically set the language to be used, with
6845 `set language c' or `set language modula-2'.
6849 GDB now has preliminary support for the GNU Modula-2 compiler,
6850 currently under development at the State University of New York at
6851 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6852 continue through the fall of 1991 and into 1992.
6854 Other Modula-2 compilers are currently not supported, and attempting to
6855 debug programs compiled with them will likely result in an error as the
6856 symbol table is read. Feel free to work on it, though!
6858 There are hooks in GDB for strict type checking and range checking,
6859 in the `Modula-2 philosophy', but they do not currently work.
6863 GDB can now write to executable and core files (e.g. patch
6864 a variable's value). You must turn this switch on, specify
6865 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6866 by assigning a new value to a variable. Modifications take
6869 * Automatic SunOS shared library reading
6871 When you run your program, GDB automatically determines where its
6872 shared libraries (if any) have been loaded, and reads their symbols.
6873 The `share' command is no longer needed. This also works when
6874 examining core files.
6878 You can specify the number of lines that the `list' command shows.
6881 * New machines supported (host and target)
6883 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6884 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6885 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6887 * New hosts supported (not targets)
6889 IBM RT/PC: romp-ibm-aix or rtpc
6891 * New targets supported (not hosts)
6893 AMD 29000 embedded with COFF a29k-none-coff
6894 AMD 29000 embedded with a.out a29k-none-aout
6895 Ultracomputer remote kernel debug a29k-nyu-kern
6897 * New remote interfaces
6903 *** Changes in GDB-4.0:
6907 Wide output is wrapped at good places to make the output more readable.
6909 Gdb now supports cross-debugging from a host machine of one type to a
6910 target machine of another type. Communication with the target system
6911 is over serial lines. The ``target'' command handles connecting to the
6912 remote system; the ``load'' command will download a program into the
6913 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6914 also supports debugging of realtime processes running under VxWorks,
6915 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6916 stub on the target system.
6918 New CPUs supported include the AMD 29000 and Intel 960.
6920 GDB now reads object files and symbol tables via a ``binary file''
6921 library, which allows a single copy of GDB to debug programs of multiple
6922 object file types such as a.out and coff.
6924 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6925 refcard.dvi and refcard.ps are available to format it).
6928 * Control-Variable user interface simplified
6930 All variables that control the operation of the debugger can be set
6931 by the ``set'' command, and displayed by the ``show'' command.
6933 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6934 ``Show prompt'' produces the response:
6935 Gdb's prompt is new-gdb=>.
6937 What follows are the NEW set commands. The command ``help set'' will
6938 print a complete list of old and new set commands. ``help set FOO''
6939 will give a longer description of the variable FOO. ``show'' will show
6940 all of the variable descriptions and their current settings.
6942 confirm on/off: Enables warning questions for operations that are
6943 hard to recover from, e.g. rerunning the program while
6944 it is already running. Default is ON.
6946 editing on/off: Enables EMACS style command line editing
6947 of input. Previous lines can be recalled with
6948 control-P, the current line can be edited with control-B,
6949 you can search for commands with control-R, etc.
6952 history filename NAME: NAME is where the gdb command history
6953 will be stored. The default is .gdb_history,
6954 or the value of the environment variable
6957 history size N: The size, in commands, of the command history. The
6958 default is 256, or the value of the environment variable
6961 history save on/off: If this value is set to ON, the history file will
6962 be saved after exiting gdb. If set to OFF, the
6963 file will not be saved. The default is OFF.
6965 history expansion on/off: If this value is set to ON, then csh-like
6966 history expansion will be performed on
6967 command line input. The default is OFF.
6969 radix N: Sets the default radix for input and output. It can be set
6970 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6971 in the current radix, so "set radix 10" is always a no-op.
6973 height N: This integer value is the number of lines on a page. Default
6974 is 24, the current `stty rows'' setting, or the ``li#''
6975 setting from the termcap entry matching the environment
6978 width N: This integer value is the number of characters on a line.
6979 Default is 80, the current `stty cols'' setting, or the ``co#''
6980 setting from the termcap entry matching the environment
6983 Note: ``set screensize'' is obsolete. Use ``set height'' and
6984 ``set width'' instead.
6986 print address on/off: Print memory addresses in various command displays,
6987 such as stack traces and structure values. Gdb looks
6988 more ``symbolic'' if you turn this off; it looks more
6989 ``machine level'' with it on. Default is ON.
6991 print array on/off: Prettyprint arrays. New convenient format! Default
6994 print demangle on/off: Print C++ symbols in "source" form if on,
6997 print asm-demangle on/off: Same, for assembler level printouts
7000 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
7003 * Support for Epoch Environment.
7005 The epoch environment is a version of Emacs v18 with windowing. One
7006 new command, ``inspect'', is identical to ``print'', except that if you
7007 are running in the epoch environment, the value is printed in its own
7011 * Support for Shared Libraries
7013 GDB can now debug programs and core files that use SunOS shared libraries.
7014 Symbols from a shared library cannot be referenced
7015 before the shared library has been linked with the program (this
7016 happens after you type ``run'' and before the function main() is entered).
7017 At any time after this linking (including when examining core files
7018 from dynamically linked programs), gdb reads the symbols from each
7019 shared library when you type the ``sharedlibrary'' command.
7020 It can be abbreviated ``share''.
7022 sharedlibrary REGEXP: Load shared object library symbols for files
7023 matching a unix regular expression. No argument
7024 indicates to load symbols for all shared libraries.
7026 info sharedlibrary: Status of loaded shared libraries.
7031 A watchpoint stops execution of a program whenever the value of an
7032 expression changes. Checking for this slows down execution
7033 tremendously whenever you are in the scope of the expression, but is
7034 quite useful for catching tough ``bit-spreader'' or pointer misuse
7035 problems. Some machines such as the 386 have hardware for doing this
7036 more quickly, and future versions of gdb will use this hardware.
7038 watch EXP: Set a watchpoint (breakpoint) for an expression.
7040 info watchpoints: Information about your watchpoints.
7042 delete N: Deletes watchpoint number N (same as breakpoints).
7043 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
7044 enable N: Re-enables watchpoint number N (same as breakpoints).
7047 * C++ multiple inheritance
7049 When used with a GCC version 2 compiler, GDB supports multiple inheritance
7052 * C++ exception handling
7054 Gdb now supports limited C++ exception handling. Besides the existing
7055 ability to breakpoint on an exception handler, gdb can breakpoint on
7056 the raising of an exception (before the stack is peeled back to the
7059 catch FOO: If there is a FOO exception handler in the dynamic scope,
7060 set a breakpoint to catch exceptions which may be raised there.
7061 Multiple exceptions (``catch foo bar baz'') may be caught.
7063 info catch: Lists all exceptions which may be caught in the
7064 current stack frame.
7067 * Minor command changes
7069 The command ``call func (arg, arg, ...)'' now acts like the print
7070 command, except it does not print or save a value if the function's result
7071 is void. This is similar to dbx usage.
7073 The ``up'' and ``down'' commands now always print the frame they end up
7074 at; ``up-silently'' and `down-silently'' can be used in scripts to change
7075 frames without printing.
7077 * New directory command
7079 'dir' now adds directories to the FRONT of the source search path.
7080 The path starts off empty. Source files that contain debug information
7081 about the directory in which they were compiled can be found even
7082 with an empty path; Sun CC and GCC include this information. If GDB can't
7083 find your source file in the current directory, type "dir .".
7085 * Configuring GDB for compilation
7087 For normal use, type ``./configure host''. See README or gdb.texinfo
7090 GDB now handles cross debugging. If you are remotely debugging between
7091 two different machines, type ``./configure host -target=targ''.
7092 Host is the machine where GDB will run; targ is the machine
7093 where the program that you are debugging will run.