1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 5.2:
6 * New native configurations
8 Alpha NetBSD alpha*-*-netbsd*
10 * Changes in Alpha configurations.
12 Multi-arch support is enabled for all Alpha configurations.
14 * New command "set max-user-call-depth <nnn>"
16 This command allows the user to limit the call depth of user-defined
17 commands. The default is 1024.
19 * Changes in FreeBSD/i386 native debugging.
21 Support for the "generate-core-file" has been added.
23 * New commands "dump", "append", and "restore".
25 These commands allow data to be copied from target memory
26 to a bfd-format or binary file (dump and append), and back
27 from a file into memory (restore).
29 *** Changes in GDB 5.2:
31 * New command "set trust-readonly-sections on[off]".
33 This command is a hint that tells gdb that read-only sections
34 really are read-only (ie. that their contents will not change).
35 In this mode, gdb will go to the object file rather than the
36 target to read memory from read-only sections (such as ".text").
37 This can be a significant performance improvement on some
38 (notably embedded) targets.
40 * New command "generate-core-file" (or "gcore").
42 This new gdb command allows the user to drop a core file of the child
43 process state at any time. So far it's been implemented only for
44 GNU/Linux and Solaris, but should be relatively easily ported to other
45 hosts. Argument is core file name (defaults to core.<pid>).
47 * New command line option
49 GDB now accepts --pid or -p followed by a process id.
51 * Change in command line behavior -- corefiles vs. process ids.
53 There is a subtle behavior in the way in which GDB handles
54 command line arguments. The first non-flag argument is always
55 a program to debug, but the second non-flag argument may either
56 be a corefile or a process id. Previously, GDB would attempt to
57 open the second argument as a corefile, and if that failed, would
58 issue a superfluous error message and then attempt to attach it as
59 a process. Now, if the second argument begins with a non-digit,
60 it will be treated as a corefile. If it begins with a digit,
61 GDB will attempt to attach it as a process, and if no such process
62 is found, will then attempt to open it as a corefile.
64 * Changes in ARM configurations.
66 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
67 configuration is fully multi-arch.
69 * New native configurations
71 ARM NetBSD arm*-*-netbsd*
72 x86 OpenBSD i[3456]86-*-openbsd*
73 AMD x86-64 running GNU/Linux x86_64-*-linux-*
74 Sparc64 running FreeBSD sparc64-*-freebsd*
78 Sanyo XStormy16 xstormy16-elf
80 * OBSOLETE configurations and files
82 Configurations that have been declared obsolete in this release have
83 been commented out. Unless there is activity to revive these
84 configurations, the next release of GDB will have their sources
87 AMD 29k family via UDI a29k-amd-udi, udi29k
88 A29K VxWorks a29k-*-vxworks
89 AMD 29000 embedded, using EBMON a29k-none-none
90 AMD 29000 embedded with COFF a29k-none-coff
91 AMD 29000 embedded with a.out a29k-none-aout
93 testsuite/gdb.hp/gdb.threads-hp/ directory
95 * REMOVED configurations and files
97 TI TMS320C80 tic80-*-*
99 PowerPC Solaris powerpcle-*-solaris*
100 PowerPC Windows NT powerpcle-*-cygwin32
101 PowerPC Netware powerpc-*-netware*
102 Harris/CXUX m88k m88*-harris-cxux*
103 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
104 ns32k-utek-sysv* ns32k-utek-*
105 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
106 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
107 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
108 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
109 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
111 * Changes to command line processing
113 The new `--args' feature can be used to specify command-line arguments
114 for the inferior from gdb's command line.
116 * Changes to key bindings
118 There is a new `operate-and-get-next' function bound to `C-o'.
120 *** Changes in GDB 5.1.1
122 Fix compile problem on DJGPP.
124 Fix a problem with floating-point registers on the i386 being
127 Fix to stop GDB crashing on .debug_str debug info.
129 Numerous documentation fixes.
131 Numerous testsuite fixes.
133 *** Changes in GDB 5.1:
135 * New native configurations
137 Alpha FreeBSD alpha*-*-freebsd*
138 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
139 MIPS GNU/Linux mips*-*-linux*
140 MIPS SGI Irix 6.x mips*-sgi-irix6*
142 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
146 Motorola 68HC11 and 68HC12 m68hc11-elf
148 UltraSparc running GNU/Linux sparc64-*-linux*
150 * OBSOLETE configurations and files
152 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
153 Harris/CXUX m88k m88*-harris-cxux*
154 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
155 ns32k-utek-sysv* ns32k-utek-*
156 TI TMS320C80 tic80-*-*
158 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
159 PowerPC Solaris powerpcle-*-solaris*
160 PowerPC Windows NT powerpcle-*-cygwin32
161 PowerPC Netware powerpc-*-netware*
162 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
163 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
164 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
165 Apple Macintosh (MPW) host N/A
167 stuff.c (Program to stuff files into a specially prepared space in kdb)
168 kdb-start.c (Main loop for the standalone kernel debugger)
170 Configurations that have been declared obsolete in this release have
171 been commented out. Unless there is activity to revive these
172 configurations, the next release of GDB will have their sources
175 * REMOVED configurations and files
177 Altos 3068 m68*-altos-*
178 Convex c1-*-*, c2-*-*
180 ARM RISCix arm-*-* (as host)
184 * GDB has been converted to ISO C.
186 GDB's source code has been converted to ISO C. In particular, the
187 sources are fully protoized, and rely on standard headers being
192 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
194 * The MI enabled by default.
196 The new machine oriented interface (MI) introduced in GDB 5.0 has been
197 revised and enabled by default. Packages which use GDB as a debugging
198 engine behind a UI or another front end are encouraged to switch to
199 using the GDB/MI interface, instead of the old annotations interface
200 which is now deprecated.
202 * Support for debugging Pascal programs.
204 GDB now includes support for debugging Pascal programs. The following
205 main features are supported:
207 - Pascal-specific data types such as sets;
209 - automatic recognition of Pascal sources based on file-name
212 - Pascal-style display of data types, variables, and functions;
214 - a Pascal expression parser.
216 However, some important features are not yet supported.
218 - Pascal string operations are not supported at all;
220 - there are some problems with boolean types;
222 - Pascal type hexadecimal constants are not supported
223 because they conflict with the internal variables format;
225 - support for Pascal objects and classes is not full yet;
227 - unlike Pascal, GDB is case-sensitive for symbol names.
229 * Changes in completion.
231 Commands such as `shell', `run' and `set args', which pass arguments
232 to inferior programs, now complete on file names, similar to what
233 users expect at the shell prompt.
235 Commands which accept locations, such as `disassemble', `print',
236 `breakpoint', `until', etc. now complete on filenames as well as
237 program symbols. Thus, if you type "break foob TAB", and the source
238 files linked into the programs include `foobar.c', that file name will
239 be one of the candidates for completion. However, file names are not
240 considered for completion after you typed a colon that delimits a file
241 name from a name of a function in that file, as in "break foo.c:bar".
243 `set demangle-style' completes on available demangling styles.
245 * New platform-independent commands:
247 It is now possible to define a post-hook for a command as well as a
248 hook that runs before the command. For more details, see the
249 documentation of `hookpost' in the GDB manual.
251 * Changes in GNU/Linux native debugging.
253 Support for debugging multi-threaded programs has been completely
254 revised for all platforms except m68k and sparc. You can now debug as
255 many threads as your system allows you to have.
257 Attach/detach is supported for multi-threaded programs.
259 Support for SSE registers was added for x86. This doesn't work for
260 multi-threaded programs though.
262 * Changes in MIPS configurations.
264 Multi-arch support is enabled for all MIPS configurations.
266 GDB can now be built as native debugger on SGI Irix 6.x systems for
267 debugging n32 executables. (Debugging 64-bit executables is not yet
270 * Unified support for hardware watchpoints in all x86 configurations.
272 Most (if not all) native x86 configurations support hardware-assisted
273 breakpoints and watchpoints in a unified manner. This support
274 implements debug register sharing between watchpoints, which allows to
275 put a virtually infinite number of watchpoints on the same address,
276 and also supports watching regions up to 16 bytes with several debug
279 The new maintenance command `maintenance show-debug-regs' toggles
280 debugging print-outs in functions that insert, remove, and test
281 watchpoints and hardware breakpoints.
283 * Changes in the DJGPP native configuration.
285 New command ``info dos sysinfo'' displays assorted information about
286 the CPU, OS, memory, and DPMI server.
288 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
289 display information about segment descriptors stored in GDT, LDT, and
292 New commands ``info dos pde'' and ``info dos pte'' display entries
293 from Page Directory and Page Tables (for now works with CWSDPMI only).
294 New command ``info dos address-pte'' displays the Page Table entry for
295 a given linear address.
297 GDB can now pass command lines longer than 126 characters to the
298 program being debugged (requires an update to the libdbg.a library
299 which is part of the DJGPP development kit).
301 DWARF2 debug info is now supported.
303 It is now possible to `step' and `next' through calls to `longjmp'.
305 * Changes in documentation.
307 All GDB documentation was converted to GFDL, the GNU Free
308 Documentation License.
310 Tracepoints-related commands are now fully documented in the GDB
313 TUI, the Text-mode User Interface, is now documented in the manual.
315 Tracepoints-related commands are now fully documented in the GDB
318 The "GDB Internals" manual now has an index. It also includes
319 documentation of `ui_out' functions, GDB coding standards, x86
320 hardware watchpoints, and memory region attributes.
322 * GDB's version number moved to ``version.in''
324 The Makefile variable VERSION has been replaced by the file
325 ``version.in''. People creating GDB distributions should update the
326 contents of this file.
330 GUD support is now a standard part of the EMACS distribution.
332 *** Changes in GDB 5.0:
334 * Improved support for debugging FP programs on x86 targets
336 Unified and much-improved support for debugging floating-point
337 programs on all x86 targets. In particular, ``info float'' now
338 displays the FP registers in the same format on all x86 targets, with
339 greater level of detail.
341 * Improvements and bugfixes in hardware-assisted watchpoints
343 It is now possible to watch array elements, struct members, and
344 bitfields with hardware-assisted watchpoints. Data-read watchpoints
345 on x86 targets no longer erroneously trigger when the address is
348 * Improvements in the native DJGPP version of GDB
350 The distribution now includes all the scripts and auxiliary files
351 necessary to build the native DJGPP version on MS-DOS/MS-Windows
352 machines ``out of the box''.
354 The DJGPP version can now debug programs that use signals. It is
355 possible to catch signals that happened in the debuggee, deliver
356 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
357 would kill the program being debugged.) Programs that hook hardware
358 interrupts (keyboard, timer, etc.) can also be debugged.
360 It is now possible to debug DJGPP programs that redirect their
361 standard handles or switch them to raw (as opposed to cooked) mode, or
362 even close them. The command ``run < foo > bar'' works as expected,
363 and ``info terminal'' reports useful information about the debuggee's
364 terminal, including raw/cooked mode, redirection, etc.
366 The DJGPP version now uses termios functions for console I/O, which
367 enables debugging graphics programs. Interrupting GDB with Ctrl-C
370 DOS-style file names with drive letters are now fully supported by
373 It is now possible to debug DJGPP programs that switch their working
374 directory. It is also possible to rerun the debuggee any number of
375 times without restarting GDB; thus, you can use the same setup,
376 breakpoints, etc. for many debugging sessions.
378 * New native configurations
380 ARM GNU/Linux arm*-*-linux*
381 PowerPC GNU/Linux powerpc-*-linux*
385 Motorola MCore mcore-*-*
386 x86 VxWorks i[3456]86-*-vxworks*
387 PowerPC VxWorks powerpc-*-vxworks*
388 TI TMS320C80 tic80-*-*
390 * OBSOLETE configurations
392 Altos 3068 m68*-altos-*
393 Convex c1-*-*, c2-*-*
395 ARM RISCix arm-*-* (as host)
398 Configurations that have been declared obsolete will be commented out,
399 but the code will be left in place. If there is no activity to revive
400 these configurations before the next release of GDB, the sources will
401 be permanently REMOVED.
403 * Gould support removed
405 Support for the Gould PowerNode and NP1 has been removed.
407 * New features for SVR4
409 On SVR4 native platforms (such as Solaris), if you attach to a process
410 without first loading a symbol file, GDB will now attempt to locate and
411 load symbols from the running process's executable file.
413 * Many C++ enhancements
415 C++ support has been greatly improved. Overload resolution now works properly
416 in almost all cases. RTTI support is on the way.
418 * Remote targets can connect to a sub-program
420 A popen(3) style serial-device has been added. This device starts a
421 sub-process (such as a stand-alone simulator) and then communicates
422 with that. The sub-program to run is specified using the syntax
423 ``|<program> <args>'' vis:
425 (gdb) set remotedebug 1
426 (gdb) target extended-remote |mn10300-elf-sim program-args
428 * MIPS 64 remote protocol
430 A long standing bug in the mips64 remote protocol where by GDB
431 expected certain 32 bit registers (ex SR) to be transfered as 32
432 instead of 64 bits has been fixed.
434 The command ``set remote-mips64-transfers-32bit-regs on'' has been
435 added to provide backward compatibility with older versions of GDB.
437 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
439 The command ``set remotebinarydownload'' command has been replaced by
440 ``set remote X-packet''. Other commands in ``set remote'' family
441 include ``set remote P-packet''.
443 * Breakpoint commands accept ranges.
445 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
446 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
447 ``tracepoint passcount'' also accepts a range of tracepoints.
449 * ``apropos'' command added.
451 The ``apropos'' command searches through command names and
452 documentation strings, printing out matches, making it much easier to
453 try to find a command that does what you are looking for.
457 A new machine oriented interface (MI) has been added to GDB. This
458 interface is designed for debug environments running GDB as a separate
459 process. This is part of the long term libGDB project. See the
460 "GDB/MI" chapter of the GDB manual for further information. It can be
461 enabled by configuring with:
463 .../configure --enable-gdbmi
465 *** Changes in GDB-4.18:
467 * New native configurations
469 HP-UX 10.20 hppa*-*-hpux10.20
470 HP-UX 11.x hppa*-*-hpux11.0*
471 M68K GNU/Linux m68*-*-linux*
475 Fujitsu FR30 fr30-*-elf*
476 Intel StrongARM strongarm-*-*
477 Mitsubishi D30V d30v-*-*
479 * OBSOLETE configurations
481 Gould PowerNode, NP1 np1-*-*, pn-*-*
483 Configurations that have been declared obsolete will be commented out,
484 but the code will be left in place. If there is no activity to revive
485 these configurations before the next release of GDB, the sources will
486 be permanently REMOVED.
490 As a compatibility experiment, GDB's source files buildsym.h and
491 buildsym.c have been converted to pure standard C, no longer
492 containing any K&R compatibility code. We believe that all systems in
493 use today either come with a standard C compiler, or have a GCC port
494 available. If this is not true, please report the affected
495 configuration to bug-gdb@gnu.org immediately. See the README file for
496 information about getting a standard C compiler if you don't have one
501 GDB now uses readline 2.2.
503 * set extension-language
505 You can now control the mapping between filename extensions and source
506 languages by using the `set extension-language' command. For instance,
507 you can ask GDB to treat .c files as C++ by saying
508 set extension-language .c c++
509 The command `info extensions' lists all of the recognized extensions
510 and their associated languages.
512 * Setting processor type for PowerPC and RS/6000
514 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
515 you can use the `set processor' command to specify what variant of the
516 PowerPC family you are debugging. The command
520 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
521 following PowerPC and RS6000 variants:
523 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
524 rs6000 IBM RS6000 ("POWER") architecture, user-level view
526 403GC IBM PowerPC 403GC
527 505 Motorola PowerPC 505
528 860 Motorola PowerPC 860 or 850
529 601 Motorola PowerPC 601
530 602 Motorola PowerPC 602
531 603 Motorola/IBM PowerPC 603 or 603e
532 604 Motorola PowerPC 604 or 604e
533 750 Motorola/IBM PowerPC 750 or 750
535 At the moment, this command just tells GDB what to name the
536 special-purpose processor registers. Since almost all the affected
537 registers are inaccessible to user-level programs, this command is
538 only useful for remote debugging in its present form.
542 Thanks to a major code donation from Hewlett-Packard, GDB now has much
543 more extensive support for HP-UX. Added features include shared
544 library support, kernel threads and hardware watchpoints for 11.00,
545 support for HP's ANSI C and C++ compilers, and a compatibility mode
546 for xdb and dbx commands.
550 HP's donation includes the new concept of catchpoints, which is a
551 generalization of the old catch command. On HP-UX, it is now possible
552 to catch exec, fork, and vfork, as well as library loading.
554 This means that the existing catch command has changed; its first
555 argument now specifies the type of catch to be set up. See the
556 output of "help catch" for a list of catchpoint types.
558 * Debugging across forks
560 On HP-UX, you can choose which process to debug when a fork() happens
565 HP has donated a curses-based terminal user interface (TUI). To get
566 it, build with --enable-tui. Although this can be enabled for any
567 configuration, at present it only works for native HP debugging.
569 * GDB remote protocol additions
571 A new protocol packet 'X' that writes binary data is now available.
572 Default behavior is to try 'X', then drop back to 'M' if the stub
573 fails to respond. The settable variable `remotebinarydownload'
574 allows explicit control over the use of 'X'.
576 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
577 full 64-bit address. The command
579 set remoteaddresssize 32
581 can be used to revert to the old behaviour. For existing remote stubs
582 the change should not be noticed, as the additional address information
585 In order to assist in debugging stubs, you may use the maintenance
586 command `packet' to send any text string to the stub. For instance,
588 maint packet heythere
590 sends the packet "$heythere#<checksum>". Note that it is very easy to
591 disrupt a debugging session by sending the wrong packet at the wrong
594 The compare-sections command allows you to compare section data on the
595 target to what is in the executable file without uploading or
596 downloading, by comparing CRC checksums.
598 * Tracing can collect general expressions
600 You may now collect general expressions at tracepoints. This requires
601 further additions to the target-side stub; see tracepoint.c and
602 doc/agentexpr.texi for further details.
604 * mask-address variable for Mips
606 For Mips targets, you may control the zeroing of the upper 32 bits of
607 a 64-bit address by entering `set mask-address on'. This is mainly
608 of interest to users of embedded R4xxx and R5xxx processors.
610 * Higher serial baud rates
612 GDB's serial code now allows you to specify baud rates 57600, 115200,
613 230400, and 460800 baud. (Note that your host system may not be able
614 to achieve all of these rates.)
618 The i960 configuration now includes an initial implementation of a
619 builtin simulator, contributed by Jim Wilson.
622 *** Changes in GDB-4.17:
624 * New native configurations
626 Alpha GNU/Linux alpha*-*-linux*
627 Unixware 2.x i[3456]86-unixware2*
628 Irix 6.x mips*-sgi-irix6*
629 PowerPC GNU/Linux powerpc-*-linux*
630 PowerPC Solaris powerpcle-*-solaris*
631 Sparc GNU/Linux sparc-*-linux*
632 Motorola sysV68 R3V7.1 m68k-motorola-sysv
636 Argonaut Risc Chip (ARC) arc-*-*
637 Hitachi H8/300S h8300*-*-*
638 Matsushita MN10200 w/simulator mn10200-*-*
639 Matsushita MN10300 w/simulator mn10300-*-*
640 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
641 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
642 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
643 Mitsubishi D10V w/simulator d10v-*-*
644 Mitsubishi M32R/D w/simulator m32r-*-elf*
645 Tsqware Sparclet sparclet-*-*
646 NEC V850 w/simulator v850-*-*
648 * New debugging protocols
650 ARM with RDI protocol arm*-*-*
651 M68K with dBUG monitor m68*-*-{aout,coff,elf}
652 DDB and LSI variants of PMON protocol mips*-*-*
653 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
654 PowerPC with SDS protocol powerpc{,le}-*-eabi
655 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
659 All configurations can now understand and use the DWARF 2 debugging
660 format. The choice is automatic, if the symbol file contains DWARF 2
665 GDB now includes basic Java language support. This support is
666 only useful with Java compilers that produce native machine code.
668 * solib-absolute-prefix and solib-search-path
670 For SunOS and SVR4 shared libraries, you may now set the prefix for
671 loading absolute shared library symbol files, and the search path for
672 locating non-absolute shared library symbol files.
674 * Live range splitting
676 GDB can now effectively debug code for which GCC has performed live
677 range splitting as part of its optimization. See gdb/doc/LRS for
678 more details on the expected format of the stabs information.
682 GDB's support for the GNU Hurd, including thread debugging, has been
683 updated to work with current versions of the Hurd.
687 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
688 instruction set. ARM GDB automatically detects when Thumb
689 instructions are in use, and adjusts disassembly and backtracing
694 GDB's MIPS target configurations now handle the MIP16 16-bit
699 GDB now includes support for overlays; if an executable has been
700 linked such that multiple sections are based at the same address, GDB
701 will decide which section to use for symbolic info. You can choose to
702 control the decision manually, using overlay commands, or implement
703 additional target-side support and use "overlay load-target" to bring
704 in the overlay mapping. Do "help overlay" for more detail.
708 The command "info symbol <address>" displays information about
709 the symbol at the specified address.
713 The standard remote protocol now includes an extension that allows
714 asynchronous collection and display of trace data. This requires
715 extensive support in the target-side debugging stub. Tracing mode
716 includes a new interaction mode in GDB and new commands: see the
717 file tracepoint.c for more details.
721 Configurations for embedded MIPS now include a simulator contributed
722 by Cygnus Solutions. The simulator supports the instruction sets
723 of most MIPS variants.
727 Sparc configurations may now include the ERC32 simulator contributed
728 by the European Space Agency. The simulator is not built into
729 Sparc targets by default; configure with --enable-sim to include it.
733 For target configurations that may include multiple variants of a
734 basic architecture (such as MIPS and SH), you may now set the
735 architecture explicitly. "set arch" sets, "info arch" lists
736 the possible architectures.
738 *** Changes in GDB-4.16:
740 * New native configurations
742 Windows 95, x86 Windows NT i[345]86-*-cygwin32
743 M68K NetBSD m68k-*-netbsd*
744 PowerPC AIX 4.x powerpc-*-aix*
745 PowerPC MacOS powerpc-*-macos*
746 PowerPC Windows NT powerpcle-*-cygwin32
747 RS/6000 AIX 4.x rs6000-*-aix4*
751 ARM with RDP protocol arm-*-*
752 I960 with MON960 i960-*-coff
753 MIPS VxWorks mips*-*-vxworks*
754 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
755 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
757 Matra Sparclet sparclet-*-*
761 The powerpc-eabi configuration now includes the PSIM simulator,
762 contributed by Andrew Cagney, with assistance from Mike Meissner.
763 PSIM is a very elaborate model of the PowerPC, including not only
764 basic instruction set execution, but also details of execution unit
765 performance and I/O hardware. See sim/ppc/README for more details.
769 GDB now works with Solaris 2.5.
771 * Windows 95/NT native
773 GDB will now work as a native debugger on Windows 95 and Windows NT.
774 To build it from source, you must use the "gnu-win32" environment,
775 which uses a DLL to emulate enough of Unix to run the GNU tools.
776 Further information, binaries, and sources are available at
777 ftp.cygnus.com, under pub/gnu-win32.
779 * dont-repeat command
781 If a user-defined command includes the command `dont-repeat', then the
782 command will not be repeated if the user just types return. This is
783 useful if the command is time-consuming to run, so that accidental
784 extra keystrokes don't run the same command many times.
786 * Send break instead of ^C
788 The standard remote protocol now includes an option to send a break
789 rather than a ^C to the target in order to interrupt it. By default,
790 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
792 * Remote protocol timeout
794 The standard remote protocol includes a new variable `remotetimeout'
795 that allows you to set the number of seconds before GDB gives up trying
796 to read from the target. The default value is 2.
798 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
800 By default GDB will automatically keep track of objects as they are
801 loaded and unloaded by the dynamic linker. By using the command `set
802 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
803 when shared library events occur, thus allowing you to set breakpoints
804 in shared libraries which are explicitly loaded by the inferior.
806 Note this feature does not work on hpux8. On hpux9 you must link
807 /usr/lib/end.o into your program. This feature should work
808 automatically on hpux10.
810 * Irix 5.x hardware watchpoint support
812 Irix 5 configurations now support the use of hardware watchpoints.
814 * Mips protocol "SYN garbage limit"
816 When debugging a Mips target using the `target mips' protocol, you
817 may set the number of characters that GDB will ignore by setting
818 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
819 every character. The default value is 1050.
821 * Recording and replaying remote debug sessions
823 If you set `remotelogfile' to the name of a file, gdb will write to it
824 a recording of a remote debug session. This recording may then be
825 replayed back to gdb using "gdbreplay". See gdbserver/README for
826 details. This is useful when you have a problem with GDB while doing
827 remote debugging; you can make a recording of the session and send it
828 to someone else, who can then recreate the problem.
830 * Speedups for remote debugging
832 GDB includes speedups for downloading and stepping MIPS systems using
833 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
834 and more efficient S-record downloading.
836 * Memory use reductions and statistics collection
838 GDB now uses less memory and reports statistics about memory usage.
839 Try the `maint print statistics' command, for example.
841 *** Changes in GDB-4.15:
845 The symbol reader for AIX GDB now uses partial symbol tables. This
846 can greatly improve startup time, especially for large executables.
848 * Remote targets use caching
850 Remote targets now use a data cache to speed up communication with the
851 remote side. The data cache could lead to incorrect results because
852 it doesn't know about volatile variables, thus making it impossible to
853 debug targets which use memory mapped I/O devices. `set remotecache
854 off' turns the the data cache off.
856 * Remote targets may have threads
858 The standard remote protocol now includes support for multiple threads
859 in the target system, using new protocol commands 'H' and 'T'. See
860 gdb/remote.c for details.
864 If GDB is configured with `--enable-netrom', then it will include
865 support for the NetROM ROM emulator from XLNT Designs. The NetROM
866 acts as though it is a bank of ROM on the target board, but you can
867 write into it over the network. GDB's support consists only of
868 support for fast loading into the emulated ROM; to debug, you must use
869 another protocol, such as standard remote protocol. The usual
870 sequence is something like
872 target nrom <netrom-hostname>
874 target remote <netrom-hostname>:1235
878 GDB now includes support for the Apple Macintosh, as a host only. It
879 may be run as either an MPW tool or as a standalone application, and
880 it can debug through the serial port. All the usual GDB commands are
881 available, but to the target command, you must supply "serial" as the
882 device type instead of "/dev/ttyXX". See mpw-README in the main
883 directory for more information on how to build. The MPW configuration
884 scripts */mpw-config.in support only a few targets, and only the
885 mips-idt-ecoff target has been tested.
889 GDB configuration now uses autoconf. This is not user-visible,
890 but does simplify configuration and building.
894 GDB now supports hpux10.
896 *** Changes in GDB-4.14:
898 * New native configurations
900 x86 FreeBSD i[345]86-*-freebsd
901 x86 NetBSD i[345]86-*-netbsd
902 NS32k NetBSD ns32k-*-netbsd
903 Sparc NetBSD sparc-*-netbsd
907 A29K VxWorks a29k-*-vxworks
908 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
909 CPU32 EST-300 emulator m68*-*-est*
910 PowerPC ELF powerpc-*-elf
913 * Alpha OSF/1 support for procfs
915 GDB now supports procfs under OSF/1-2.x and higher, which makes it
916 possible to attach to running processes. As the mounting of the /proc
917 filesystem is optional on the Alpha, GDB automatically determines
918 the availability of /proc during startup. This can lead to problems
919 if /proc is unmounted after GDB has been started.
921 * Arguments to user-defined commands
923 User commands may accept up to 10 arguments separated by whitespace.
924 Arguments are accessed within the user command via $arg0..$arg9. A
927 print $arg0 + $arg1 + $arg2
929 To execute the command use:
932 Defines the command "adder" which prints the sum of its three arguments.
933 Note the arguments are text substitutions, so they may reference variables,
934 use complex expressions, or even perform inferior function calls.
936 * New `if' and `while' commands
938 This makes it possible to write more sophisticated user-defined
939 commands. Both commands take a single argument, which is the
940 expression to evaluate, and must be followed by the commands to
941 execute, one per line, if the expression is nonzero, the list being
942 terminated by the word `end'. The `if' command list may include an
943 `else' word, which causes the following commands to be executed only
944 if the expression is zero.
946 * Fortran source language mode
948 GDB now includes partial support for Fortran 77. It will recognize
949 Fortran programs and can evaluate a subset of Fortran expressions, but
950 variables and functions may not be handled correctly. GDB will work
951 with G77, but does not yet know much about symbols emitted by other
954 * Better HPUX support
956 Most debugging facilities now work on dynamic executables for HPPAs
957 running hpux9 or later. You can attach to running dynamically linked
958 processes, but by default the dynamic libraries will be read-only, so
959 for instance you won't be able to put breakpoints in them. To change
960 that behavior do the following before running the program:
966 This will cause the libraries to be mapped private and read-write.
967 To revert to the normal behavior, do this:
973 You cannot set breakpoints or examine data in the library until after
974 the library is loaded if the function/data symbols do not have
977 GDB can now also read debug symbols produced by the HP C compiler on
978 HPPAs (sorry, no C++, Fortran or 68k support).
980 * Target byte order now dynamically selectable
982 You can choose which byte order to use with a target system, via the
983 commands "set endian big" and "set endian little", and you can see the
984 current setting by using "show endian". You can also give the command
985 "set endian auto", in which case GDB will use the byte order
986 associated with the executable. Currently, only embedded MIPS
987 configurations support dynamic selection of target byte order.
989 * New DOS host serial code
991 This version uses DPMI interrupts to handle buffered I/O, so you
992 no longer need to run asynctsr when debugging boards connected to
995 *** Changes in GDB-4.13:
997 * New "complete" command
999 This lists all the possible completions for the rest of the line, if it
1000 were to be given as a command itself. This is intended for use by emacs.
1002 * Trailing space optional in prompt
1004 "set prompt" no longer adds a space for you after the prompt you set. This
1005 allows you to set a prompt which ends in a space or one that does not.
1007 * Breakpoint hit counts
1009 "info break" now displays a count of the number of times the breakpoint
1010 has been hit. This is especially useful in conjunction with "ignore"; you
1011 can ignore a large number of breakpoint hits, look at the breakpoint info
1012 to see how many times the breakpoint was hit, then run again, ignoring one
1013 less than that number, and this will get you quickly to the last hit of
1016 * Ability to stop printing at NULL character
1018 "set print null-stop" will cause GDB to stop printing the characters of
1019 an array when the first NULL is encountered. This is useful when large
1020 arrays actually contain only short strings.
1022 * Shared library breakpoints
1024 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
1025 breakpoints in shared libraries before the executable is run.
1027 * Hardware watchpoints
1029 There is a new hardware breakpoint for the watch command for sparclite
1030 targets. See gdb/sparclite/hw_breakpoint.note.
1032 Hardware watchpoints are also now supported under GNU/Linux.
1036 Annotations have been added. These are for use with graphical interfaces,
1037 and are still experimental. Currently only gdba.el uses these.
1039 * Improved Irix 5 support
1041 GDB now works properly with Irix 5.2.
1043 * Improved HPPA support
1045 GDB now works properly with the latest GCC and GAS.
1047 * New native configurations
1049 Sequent PTX4 i[34]86-sequent-ptx4
1050 HPPA running OSF/1 hppa*-*-osf*
1051 Atari TT running SVR4 m68*-*-sysv4*
1052 RS/6000 LynxOS rs6000-*-lynxos*
1056 OS/9000 i[34]86-*-os9k
1057 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
1060 * Hitachi SH7000 and E7000-PC ICE support
1062 There is now support for communicating with the Hitachi E7000-PC ICE.
1063 This is available automatically when GDB is configured for the SH.
1067 As usual, a variety of small fixes and improvements, both generic
1068 and configuration-specific. See the ChangeLog for more detail.
1070 *** Changes in GDB-4.12:
1072 * Irix 5 is now supported
1076 GDB-4.12 on the HPPA has a number of changes which make it unable
1077 to debug the output from the currently released versions of GCC and
1078 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
1079 of GCC and GAS, versions of these tools designed to work with GDB-4.12
1080 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
1083 *** Changes in GDB-4.11:
1085 * User visible changes:
1089 The "set remotedebug" option is now consistent between the mips remote
1090 target, remote targets using the gdb-specific protocol, UDI (AMD's
1091 debug protocol for the 29k) and the 88k bug monitor. It is now an
1092 integer specifying a debug level (normally 0 or 1, but 2 means more
1093 debugging info for the mips target).
1095 * DEC Alpha native support
1097 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
1098 debug info, but GDB works fairly well with the DEC compiler and should
1099 work with a future GCC release. See the README file for a few
1100 Alpha-specific notes.
1102 * Preliminary thread implementation
1104 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
1106 * LynxOS native and target support for 386
1108 This release has been hosted on LynxOS 2.2, and also can be configured
1109 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
1112 * Improvements in C++ mangling/demangling.
1114 This release has much better g++ debugging, specifically in name
1115 mangling/demangling, virtual function calls, print virtual table,
1116 call methods, ...etc.
1118 *** Changes in GDB-4.10:
1120 * User visible changes:
1122 Remote debugging using the GDB-specific (`target remote') protocol now
1123 supports the `load' command. This is only useful if you have some
1124 other way of getting the stub to the target system, and you can put it
1125 somewhere in memory where it won't get clobbered by the download.
1127 Filename completion now works.
1129 When run under emacs mode, the "info line" command now causes the
1130 arrow to point to the line specified. Also, "info line" prints
1131 addresses in symbolic form (as well as hex).
1133 All vxworks based targets now support a user settable option, called
1134 vxworks-timeout. This option represents the number of seconds gdb
1135 should wait for responses to rpc's. You might want to use this if
1136 your vxworks target is, perhaps, a slow software simulator or happens
1137 to be on the far side of a thin network line.
1141 This release contains support for using a DEC alpha as a GDB host for
1142 cross debugging. Native alpha debugging is not supported yet.
1145 *** Changes in GDB-4.9:
1149 This is the first GDB release which is accompanied by a matching testsuite.
1150 The testsuite requires installation of dejagnu, which should be available
1151 via ftp from most sites that carry GNU software.
1155 'Cfront' style demangling has had its name changed to 'ARM' style, to
1156 emphasize that it was written from the specifications in the C++ Annotated
1157 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
1158 disclaimers, it still generated too much confusion with users attempting to
1159 use gdb with AT&T cfront.
1163 GDB now uses a standard remote interface to a simulator library.
1164 So far, the library contains simulators for the Zilog Z8001/2, the
1165 Hitachi H8/300, H8/500 and Super-H.
1167 * New targets supported
1169 H8/300 simulator h8300-hitachi-hms or h8300hms
1170 H8/500 simulator h8500-hitachi-hms or h8500hms
1171 SH simulator sh-hitachi-hms or sh
1172 Z8000 simulator z8k-zilog-none or z8ksim
1173 IDT MIPS board over serial line mips-idt-ecoff
1175 Cross-debugging to GO32 targets is supported. It requires a custom
1176 version of the i386-stub.c module which is integrated with the
1177 GO32 memory extender.
1179 * New remote protocols
1181 MIPS remote debugging protocol.
1183 * New source languages supported
1185 This version includes preliminary support for Chill, a Pascal like language
1186 used by telecommunications companies. Chill support is also being integrated
1187 into the GNU compiler, but we don't know when it will be publically available.
1190 *** Changes in GDB-4.8:
1192 * HP Precision Architecture supported
1194 GDB now supports HP PA-RISC machines running HPUX. A preliminary
1195 version of this support was available as a set of patches from the
1196 University of Utah. GDB does not support debugging of programs
1197 compiled with the HP compiler, because HP will not document their file
1198 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
1199 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
1201 Many problems in the preliminary version have been fixed.
1203 * Faster and better demangling
1205 We have improved template demangling and fixed numerous bugs in the GNU style
1206 demangler. It can now handle type modifiers such as `static' or `const'. Wide
1207 character types (wchar_t) are now supported. Demangling of each symbol is now
1208 only done once, and is cached when the symbol table for a file is read in.
1209 This results in a small increase in memory usage for C programs, a moderate
1210 increase in memory usage for C++ programs, and a fantastic speedup in
1213 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
1214 from the specifications in the Annotated Reference Manual, which AT&T's
1215 compiler does not actually implement.
1217 * G++ multiple inheritance compiler problem
1219 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
1220 inheritance lattices was reworked to properly discover ambiguities. We
1221 recently found an example which causes this new algorithm to fail in a
1222 very subtle way, producing bad debug information for those classes.
1223 The file 'gcc.patch' (in this directory) can be applied to gcc to
1224 circumvent the problem. A future GCC release will contain a complete
1227 The previous G++ debug info problem (mentioned below for the gdb-4.7
1228 release) is fixed in gcc version 2.3.2.
1230 * Improved configure script
1232 The `configure' script will now attempt to guess your system type if
1233 you don't supply a host system type. The old scheme of supplying a
1234 host system triplet is preferable over using this. All the magic is
1235 done in the new `config.guess' script. Examine it for details.
1237 We have also brought our configure script much more in line with the FSF's
1238 version. It now supports the --with-xxx options. In particular,
1239 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
1240 The resulting GDB will not be able to read arbitrary object file formats --
1241 only the format ``expected'' to be used on the configured target system.
1242 We hope to make this the default in a future release.
1244 * Documentation improvements
1246 There's new internal documentation on how to modify GDB, and how to
1247 produce clean changes to the code. We implore people to read it
1248 before submitting changes.
1250 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
1251 M4 macros. The new texinfo.tex is provided in this release. Pre-built
1252 `info' files are also provided. To build `info' files from scratch,
1253 you will need the latest `makeinfo' release, which will be available in
1254 a future texinfo-X.Y release.
1256 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
1257 We're not sure exactly which versions have this problem, but it has
1258 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
1259 or better. If that isn't possible, there is a patch in
1260 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
1261 around this problem.
1265 GDB now supports array constants that can be used in expressions typed in by
1266 the user. The syntax is `{element, element, ...}'. Ie: you can now type
1267 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
1270 The new directory `gdb/sparclite' contains a program that demonstrates
1271 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
1273 * New native hosts supported
1275 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
1276 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
1278 * New targets supported
1280 AMD 29k family via UDI a29k-amd-udi or udi29k
1282 * New file formats supported
1284 BFD now supports reading HP/PA-RISC executables (SOM file format?),
1285 HPUX core files, and SCO 3.2v2 core files.
1289 Attaching to processes now works again; thanks for the many bug reports.
1291 We have also stomped on a bunch of core dumps caused by
1292 printf_filtered("%s") problems.
1294 We eliminated a copyright problem on the rpc and ptrace header files
1295 for VxWorks, which was discovered at the last minute during the 4.7
1296 release. You should now be able to build a VxWorks GDB.
1298 You can now interrupt gdb while an attached process is running. This
1299 will cause the attached process to stop, and give control back to GDB.
1301 We fixed problems caused by using too many file descriptors
1302 for reading symbols from object files and libraries. This was
1303 especially a problem for programs that used many (~100) shared
1306 The `step' command now only enters a subroutine if there is line number
1307 information for the subroutine. Otherwise it acts like the `next'
1308 command. Previously, `step' would enter subroutines if there was
1309 any debugging information about the routine. This avoids problems
1310 when using `cc -g1' on MIPS machines.
1312 * Internal improvements
1314 GDB's internal interfaces have been improved to make it easier to support
1315 debugging of multiple languages in the future.
1317 GDB now uses a common structure for symbol information internally.
1318 Minimal symbols (derived from linkage symbols in object files), partial
1319 symbols (from a quick scan of debug information), and full symbols
1320 contain a common subset of information, making it easier to write
1321 shared code that handles any of them.
1323 * New command line options
1325 We now accept --silent as an alias for --quiet.
1329 The memory-mapped-malloc library is now licensed under the GNU Library
1330 General Public License.
1332 *** Changes in GDB-4.7:
1334 * Host/native/target split
1336 GDB has had some major internal surgery to untangle the support for
1337 hosts and remote targets. Now, when you configure GDB for a remote
1338 target, it will no longer load in all of the support for debugging
1339 local programs on the host. When fully completed and tested, this will
1340 ensure that arbitrary host/target combinations are possible.
1342 The primary conceptual shift is to separate the non-portable code in
1343 GDB into three categories. Host specific code is required any time GDB
1344 is compiled on that host, regardless of the target. Target specific
1345 code relates to the peculiarities of the target, but can be compiled on
1346 any host. Native specific code is everything else: it can only be
1347 built when the host and target are the same system. Child process
1348 handling and core file support are two common `native' examples.
1350 GDB's use of /proc for controlling Unix child processes is now cleaner.
1351 It has been split out into a single module under the `target_ops' vector,
1352 plus two native-dependent functions for each system that uses /proc.
1354 * New hosts supported
1356 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
1357 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1358 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
1360 * New targets supported
1362 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1363 68030 and CPU32 m68030-*-*, m68332-*-*
1365 * New native hosts supported
1367 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1368 (386bsd is not well tested yet)
1369 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
1371 * New file formats supported
1373 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
1374 supports reading of `a.out.adobe' object files, which are an a.out
1375 format extended with minimal information about multiple sections.
1379 `show copying' is the same as the old `info copying'.
1380 `show warranty' is the same as `info warrantee'.
1381 These were renamed for consistency. The old commands continue to work.
1383 `info handle' is a new alias for `info signals'.
1385 You can now define pre-command hooks, which attach arbitrary command
1386 scripts to any command. The commands in the hook will be executed
1387 prior to the user's command. You can also create a hook which will be
1388 executed whenever the program stops. See gdb.texinfo.
1392 We now deal with Cfront style name mangling, and can even extract type
1393 info from mangled symbols. GDB can automatically figure out which
1394 symbol mangling style your C++ compiler uses.
1396 Calling of methods and virtual functions has been improved as well.
1400 The crash that occured when debugging Sun Ansi-C compiled binaries is
1401 fixed. This was due to mishandling of the extra N_SO stabs output
1404 We also finally got Ultrix 4.2 running in house, and fixed core file
1405 support, with help from a dozen people on the net.
1407 John M. Farrell discovered that the reason that single-stepping was so
1408 slow on all of the Mips based platforms (primarily SGI and DEC) was
1409 that we were trying to demangle and lookup a symbol used for internal
1410 purposes on every instruction that was being stepped through. Changing
1411 the name of that symbol so that it couldn't be mistaken for a C++
1412 mangled symbol sped things up a great deal.
1414 Rich Pixley sped up symbol lookups in general by getting much smarter
1415 about when C++ symbol mangling is necessary. This should make symbol
1416 completion (TAB on the command line) much faster. It's not as fast as
1417 we'd like, but it's significantly faster than gdb-4.6.
1421 A new user controllable variable 'call_scratch_address' can
1422 specify the location of a scratch area to be used when GDB
1423 calls a function in the target. This is necessary because the
1424 usual method of putting the scratch area on the stack does not work
1425 in systems that have separate instruction and data spaces.
1427 We integrated changes to support the 29k UDI (Universal Debugger
1428 Interface), but discovered at the last minute that we didn't have all
1429 of the appropriate copyright paperwork. We are working with AMD to
1430 resolve this, and hope to have it available soon.
1434 We have sped up the remote serial line protocol, especially for targets
1435 with lots of registers. It now supports a new `expedited status' ('T')
1436 message which can be used in place of the existing 'S' status message.
1437 This allows the remote stub to send only the registers that GDB
1438 needs to make a quick decision about single-stepping or conditional
1439 breakpoints, eliminating the need to fetch the entire register set for
1440 each instruction being stepped through.
1442 The GDB remote serial protocol now implements a write-through cache for
1443 registers, only re-reading the registers if the target has run.
1445 There is also a new remote serial stub for SPARC processors. You can
1446 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
1447 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
1448 processor with a serial port.
1452 Configure.in files have become much easier to read and modify. A new
1453 `table driven' format makes it more obvious what configurations are
1454 supported, and what files each one uses.
1458 There is a new opcodes library which will eventually contain all of the
1459 disassembly routines and opcode tables. At present, it only contains
1460 Sparc and Z8000 routines. This will allow the assembler, debugger, and
1461 disassembler (binutils/objdump) to share these routines.
1463 The libiberty library is now copylefted under the GNU Library General
1464 Public License. This allows more liberal use, and was done so libg++
1465 can use it. This makes no difference to GDB, since the Library License
1466 grants all the rights from the General Public License.
1470 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
1471 reference to the stabs symbol info used by the debugger. It is (as far
1472 as we know) the only published document on this fascinating topic. We
1473 encourage you to read it, compare it to the stabs information on your
1474 system, and send improvements on the document in general (to
1475 bug-gdb@prep.ai.mit.edu).
1477 And, of course, many bugs have been fixed.
1480 *** Changes in GDB-4.6:
1482 * Better support for C++ function names
1484 GDB now accepts as input the "demangled form" of C++ overloaded function
1485 names and member function names, and can do command completion on such names
1486 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
1487 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
1488 Make use of command completion, it is your friend.
1490 GDB also now accepts a variety of C++ mangled symbol formats. They are
1491 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
1492 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
1493 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
1494 for the list of formats.
1496 * G++ symbol mangling problem
1498 Recent versions of gcc have a bug in how they emit debugging information for
1499 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
1500 directory) can be applied to gcc to fix the problem. Alternatively, if you
1501 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
1502 usual symptom is difficulty with setting breakpoints on methods. GDB complains
1503 about the method being non-existent. (We believe that version 2.2.2 of GCC has
1506 * New 'maintenance' command
1508 All of the commands related to hacking GDB internals have been moved out of
1509 the main command set, and now live behind the 'maintenance' command. This
1510 can also be abbreviated as 'mt'. The following changes were made:
1512 dump-me -> maintenance dump-me
1513 info all-breakpoints -> maintenance info breakpoints
1514 printmsyms -> maintenance print msyms
1515 printobjfiles -> maintenance print objfiles
1516 printpsyms -> maintenance print psymbols
1517 printsyms -> maintenance print symbols
1519 The following commands are new:
1521 maintenance demangle Call internal GDB demangler routine to
1522 demangle a C++ link name and prints the result.
1523 maintenance print type Print a type chain for a given symbol
1525 * Change to .gdbinit file processing
1527 We now read the $HOME/.gdbinit file before processing the argv arguments
1528 (e.g. reading symbol files or core files). This allows global parameters to
1529 be set, which will apply during the symbol reading. The ./.gdbinit is still
1530 read after argv processing.
1532 * New hosts supported
1534 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
1536 GNU/Linux support i386-unknown-linux or linux
1538 We are also including code to support the HP/PA running BSD and HPUX. This
1539 is almost guaranteed not to work, as we didn't have time to test or build it
1540 for this release. We are including it so that the more adventurous (or
1541 masochistic) of you can play with it. We also had major problems with the
1542 fact that the compiler that we got from HP doesn't support the -g option.
1545 * New targets supported
1547 Hitachi H8/300 h8300-hitachi-hms or h8300hms
1549 * More smarts about finding #include files
1551 GDB now remembers the compilation directory for all include files, and for
1552 all files from which C is generated (like yacc and lex sources). This
1553 greatly improves GDB's ability to find yacc/lex sources, and include files,
1554 especially if you are debugging your program from a directory different from
1555 the one that contains your sources.
1557 We also fixed a bug which caused difficulty with listing and setting
1558 breakpoints in include files which contain C code. (In the past, you had to
1559 try twice in order to list an include file that you hadn't looked at before.)
1561 * Interesting infernals change
1563 GDB now deals with arbitrary numbers of sections, where the symbols for each
1564 section must be relocated relative to that section's landing place in the
1565 target's address space. This work was needed to support ELF with embedded
1566 stabs used by Solaris-2.0.
1568 * Bug fixes (of course!)
1570 There have been loads of fixes for the following things:
1571 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
1572 i960, stabs, DOS(GO32), procfs, etc...
1574 See the ChangeLog for details.
1576 *** Changes in GDB-4.5:
1578 * New machines supported (host and target)
1580 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
1582 SGI Irix-4.x mips-sgi-irix4 or iris4
1584 * New malloc package
1586 GDB now uses a new memory manager called mmalloc, based on gmalloc.
1587 Mmalloc is capable of handling mutiple heaps of memory. It is also
1588 capable of saving a heap to a file, and then mapping it back in later.
1589 This can be used to greatly speedup the startup of GDB by using a
1590 pre-parsed symbol table which lives in a mmalloc managed heap. For
1591 more details, please read mmalloc/mmalloc.texi.
1595 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
1596 'help info proc' for details.
1598 * MIPS ecoff symbol table format
1600 The code that reads MIPS symbol table format is now supported on all hosts.
1601 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
1604 * File name changes for MS-DOS
1606 Many files in the config directories have been renamed to make it easier to
1607 support GDB on MS-DOSe systems (which have very restrictive file name
1608 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
1609 environment) is close to working but has some remaining problems. Note
1610 that debugging of DOS programs is not supported, due to limitations
1611 in the ``operating system'', but it can be used to host cross-debugging.
1613 * Cross byte order fixes
1615 Many fixes have been made to support cross debugging of Sparc and MIPS
1616 targets from hosts whose byte order differs.
1618 * New -mapped and -readnow options
1620 If memory-mapped files are available on your system through the 'mmap'
1621 system call, you can use the -mapped option on the `file' or
1622 `symbol-file' commands to cause GDB to write the symbols from your
1623 program into a reusable file. If the program you are debugging is
1624 called `/path/fred', the mapped symbol file will be `./fred.syms'.
1625 Future GDB debugging sessions will notice the presence of this file,
1626 and will quickly map in symbol information from it, rather than reading
1627 the symbol table from the executable program. Using the '-mapped'
1628 option in a GDB `file' or `symbol-file' command has the same effect as
1629 starting GDB with the '-mapped' command-line option.
1631 You can cause GDB to read the entire symbol table immediately by using
1632 the '-readnow' option with any of the commands that load symbol table
1633 information (or on the GDB command line). This makes the command
1634 slower, but makes future operations faster.
1636 The -mapped and -readnow options are typically combined in order to
1637 build a `fred.syms' file that contains complete symbol information.
1638 A simple GDB invocation to do nothing but build a `.syms' file for future
1641 gdb -batch -nx -mapped -readnow programname
1643 The `.syms' file is specific to the host machine on which GDB is run.
1644 It holds an exact image of GDB's internal symbol table. It cannot be
1645 shared across multiple host platforms.
1647 * longjmp() handling
1649 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
1650 siglongjmp() without losing control. This feature has not yet been ported to
1651 all systems. It currently works on many 386 platforms, all MIPS-based
1652 platforms (SGI, DECstation, etc), and Sun3/4.
1656 Preliminary work has been put in to support the new Solaris OS from Sun. At
1657 this time, it can control and debug processes, but it is not capable of
1662 As always, many many bug fixes. The major areas were with g++, and mipsread.
1663 People using the MIPS-based platforms should experience fewer mysterious
1664 crashes and trashed symbol tables.
1666 *** Changes in GDB-4.4:
1668 * New machines supported (host and target)
1670 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1672 BSD Reno on Vax vax-dec-bsd
1673 Ultrix on Vax vax-dec-ultrix
1675 * New machines supported (target)
1677 AMD 29000 embedded, using EBMON a29k-none-none
1681 GDB continues to improve its handling of C++. `References' work better.
1682 The demangler has also been improved, and now deals with symbols mangled as
1683 per the Annotated C++ Reference Guide.
1685 GDB also now handles `stabs' symbol information embedded in MIPS
1686 `ecoff' symbol tables. Since the ecoff format was not easily
1687 extensible to handle new languages such as C++, this appeared to be a
1688 good way to put C++ debugging info into MIPS binaries. This option
1689 will be supported in the GNU C compiler, version 2, when it is
1692 * New features for SVR4
1694 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
1695 shared libraries. Debugging dynamically linked programs should present
1696 only minor differences from debugging statically linked programs.
1698 The `info proc' command will print out information about any process
1699 on an SVR4 system (including the one you are debugging). At the moment,
1700 it prints the address mappings of the process.
1702 If you bring up GDB on another SVR4 system, please send mail to
1703 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
1705 * Better dynamic linking support in SunOS
1707 Reading symbols from shared libraries which contain debugging symbols
1708 now works properly. However, there remain issues such as automatic
1709 skipping of `transfer vector' code during function calls, which
1710 make it harder to debug code in a shared library, than to debug the
1711 same code linked statically.
1715 GDB is now using the latest `getopt' routines from the FSF. This
1716 version accepts the -- prefix for options with long names. GDB will
1717 continue to accept the old forms (-option and +option) as well.
1718 Various single letter abbreviations for options have been explicity
1719 added to the option table so that they won't get overshadowed in the
1720 future by other options that begin with the same letter.
1724 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
1725 Many assorted bugs have been handled. Many more remain to be handled.
1726 See the various ChangeLog files (primarily in gdb and bfd) for details.
1729 *** Changes in GDB-4.3:
1731 * New machines supported (host and target)
1733 Amiga 3000 running Amix m68k-cbm-svr4 or amix
1734 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
1735 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1737 * Almost SCO Unix support
1739 We had hoped to support:
1740 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1741 (except for core file support), but we discovered very late in the release
1742 that it has problems with process groups that render gdb unusable. Sorry
1743 about that. I encourage people to fix it and post the fixes.
1745 * Preliminary ELF and DWARF support
1747 GDB can read ELF object files on System V Release 4, and can handle
1748 debugging records for C, in DWARF format, in ELF files. This support
1749 is preliminary. If you bring up GDB on another SVR4 system, please
1750 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
1755 GDB now uses the latest `readline' library. One user-visible change
1756 is that two tabs will list possible command completions, which previously
1757 required typing M-? (meta-question mark, or ESC ?).
1761 The `stepi' bug that many of you noticed has been squashed.
1762 Many bugs in C++ have been handled. Many more remain to be handled.
1763 See the various ChangeLog files (primarily in gdb and bfd) for details.
1765 * State of the MIPS world (in case you wondered):
1767 GDB can understand the symbol tables emitted by the compilers
1768 supplied by most vendors of MIPS-based machines, including DEC. These
1769 symbol tables are in a format that essentially nobody else uses.
1771 Some versions of gcc come with an assembler post-processor called
1772 mips-tfile. This program is required if you want to do source-level
1773 debugging of gcc-compiled programs. I believe FSF does not ship
1774 mips-tfile with gcc version 1, but it will eventually come with gcc
1777 Debugging of g++ output remains a problem. g++ version 1.xx does not
1778 really support it at all. (If you're lucky, you should be able to get
1779 line numbers and stack traces to work, but no parameters or local
1780 variables.) With some work it should be possible to improve the
1783 When gcc version 2 is released, you will have somewhat better luck.
1784 However, even then you will get confusing results for inheritance and
1787 We will eventually provide full debugging of g++ output on
1788 DECstations. This will probably involve some kind of stabs-in-ecoff
1789 encapulation, but the details have not been worked out yet.
1792 *** Changes in GDB-4.2:
1794 * Improved configuration
1796 Only one copy of `configure' exists now, and it is not self-modifying.
1797 Porting BFD is simpler.
1801 The `step' and `next' commands now only stop at the first instruction
1802 of a source line. This prevents the multiple stops that used to occur
1803 in switch statements, for-loops, etc. `Step' continues to stop if a
1804 function that has debugging information is called within the line.
1808 Lots of small bugs fixed. More remain.
1810 * New host supported (not target)
1812 Intel 386 PC clone running Mach i386-none-mach
1815 *** Changes in GDB-4.1:
1817 * Multiple source language support
1819 GDB now has internal scaffolding to handle several source languages.
1820 It determines the type of each source file from its filename extension,
1821 and will switch expression parsing and number formatting to match the
1822 language of the function in the currently selected stack frame.
1823 You can also specifically set the language to be used, with
1824 `set language c' or `set language modula-2'.
1828 GDB now has preliminary support for the GNU Modula-2 compiler,
1829 currently under development at the State University of New York at
1830 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
1831 continue through the fall of 1991 and into 1992.
1833 Other Modula-2 compilers are currently not supported, and attempting to
1834 debug programs compiled with them will likely result in an error as the
1835 symbol table is read. Feel free to work on it, though!
1837 There are hooks in GDB for strict type checking and range checking,
1838 in the `Modula-2 philosophy', but they do not currently work.
1842 GDB can now write to executable and core files (e.g. patch
1843 a variable's value). You must turn this switch on, specify
1844 the file ("exec foo" or "core foo"), *then* modify it, e.g.
1845 by assigning a new value to a variable. Modifications take
1848 * Automatic SunOS shared library reading
1850 When you run your program, GDB automatically determines where its
1851 shared libraries (if any) have been loaded, and reads their symbols.
1852 The `share' command is no longer needed. This also works when
1853 examining core files.
1857 You can specify the number of lines that the `list' command shows.
1860 * New machines supported (host and target)
1862 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1863 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
1864 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
1866 * New hosts supported (not targets)
1868 IBM RT/PC: romp-ibm-aix or rtpc
1870 * New targets supported (not hosts)
1872 AMD 29000 embedded with COFF a29k-none-coff
1873 AMD 29000 embedded with a.out a29k-none-aout
1874 Ultracomputer remote kernel debug a29k-nyu-kern
1876 * New remote interfaces
1882 *** Changes in GDB-4.0:
1886 Wide output is wrapped at good places to make the output more readable.
1888 Gdb now supports cross-debugging from a host machine of one type to a
1889 target machine of another type. Communication with the target system
1890 is over serial lines. The ``target'' command handles connecting to the
1891 remote system; the ``load'' command will download a program into the
1892 remote system. Serial stubs for the m68k and i386 are provided. Gdb
1893 also supports debugging of realtime processes running under VxWorks,
1894 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
1895 stub on the target system.
1897 New CPUs supported include the AMD 29000 and Intel 960.
1899 GDB now reads object files and symbol tables via a ``binary file''
1900 library, which allows a single copy of GDB to debug programs of multiple
1901 object file types such as a.out and coff.
1903 There is now a GDB reference card in "doc/refcard.tex". (Make targets
1904 refcard.dvi and refcard.ps are available to format it).
1907 * Control-Variable user interface simplified
1909 All variables that control the operation of the debugger can be set
1910 by the ``set'' command, and displayed by the ``show'' command.
1912 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
1913 ``Show prompt'' produces the response:
1914 Gdb's prompt is new-gdb=>.
1916 What follows are the NEW set commands. The command ``help set'' will
1917 print a complete list of old and new set commands. ``help set FOO''
1918 will give a longer description of the variable FOO. ``show'' will show
1919 all of the variable descriptions and their current settings.
1921 confirm on/off: Enables warning questions for operations that are
1922 hard to recover from, e.g. rerunning the program while
1923 it is already running. Default is ON.
1925 editing on/off: Enables EMACS style command line editing
1926 of input. Previous lines can be recalled with
1927 control-P, the current line can be edited with control-B,
1928 you can search for commands with control-R, etc.
1931 history filename NAME: NAME is where the gdb command history
1932 will be stored. The default is .gdb_history,
1933 or the value of the environment variable
1936 history size N: The size, in commands, of the command history. The
1937 default is 256, or the value of the environment variable
1940 history save on/off: If this value is set to ON, the history file will
1941 be saved after exiting gdb. If set to OFF, the
1942 file will not be saved. The default is OFF.
1944 history expansion on/off: If this value is set to ON, then csh-like
1945 history expansion will be performed on
1946 command line input. The default is OFF.
1948 radix N: Sets the default radix for input and output. It can be set
1949 to 8, 10, or 16. Note that the argument to "radix" is interpreted
1950 in the current radix, so "set radix 10" is always a no-op.
1952 height N: This integer value is the number of lines on a page. Default
1953 is 24, the current `stty rows'' setting, or the ``li#''
1954 setting from the termcap entry matching the environment
1957 width N: This integer value is the number of characters on a line.
1958 Default is 80, the current `stty cols'' setting, or the ``co#''
1959 setting from the termcap entry matching the environment
1962 Note: ``set screensize'' is obsolete. Use ``set height'' and
1963 ``set width'' instead.
1965 print address on/off: Print memory addresses in various command displays,
1966 such as stack traces and structure values. Gdb looks
1967 more ``symbolic'' if you turn this off; it looks more
1968 ``machine level'' with it on. Default is ON.
1970 print array on/off: Prettyprint arrays. New convenient format! Default
1973 print demangle on/off: Print C++ symbols in "source" form if on,
1976 print asm-demangle on/off: Same, for assembler level printouts
1979 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
1982 * Support for Epoch Environment.
1984 The epoch environment is a version of Emacs v18 with windowing. One
1985 new command, ``inspect'', is identical to ``print'', except that if you
1986 are running in the epoch environment, the value is printed in its own
1990 * Support for Shared Libraries
1992 GDB can now debug programs and core files that use SunOS shared libraries.
1993 Symbols from a shared library cannot be referenced
1994 before the shared library has been linked with the program (this
1995 happens after you type ``run'' and before the function main() is entered).
1996 At any time after this linking (including when examining core files
1997 from dynamically linked programs), gdb reads the symbols from each
1998 shared library when you type the ``sharedlibrary'' command.
1999 It can be abbreviated ``share''.
2001 sharedlibrary REGEXP: Load shared object library symbols for files
2002 matching a unix regular expression. No argument
2003 indicates to load symbols for all shared libraries.
2005 info sharedlibrary: Status of loaded shared libraries.
2010 A watchpoint stops execution of a program whenever the value of an
2011 expression changes. Checking for this slows down execution
2012 tremendously whenever you are in the scope of the expression, but is
2013 quite useful for catching tough ``bit-spreader'' or pointer misuse
2014 problems. Some machines such as the 386 have hardware for doing this
2015 more quickly, and future versions of gdb will use this hardware.
2017 watch EXP: Set a watchpoint (breakpoint) for an expression.
2019 info watchpoints: Information about your watchpoints.
2021 delete N: Deletes watchpoint number N (same as breakpoints).
2022 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
2023 enable N: Re-enables watchpoint number N (same as breakpoints).
2026 * C++ multiple inheritance
2028 When used with a GCC version 2 compiler, GDB supports multiple inheritance
2031 * C++ exception handling
2033 Gdb now supports limited C++ exception handling. Besides the existing
2034 ability to breakpoint on an exception handler, gdb can breakpoint on
2035 the raising of an exception (before the stack is peeled back to the
2038 catch FOO: If there is a FOO exception handler in the dynamic scope,
2039 set a breakpoint to catch exceptions which may be raised there.
2040 Multiple exceptions (``catch foo bar baz'') may be caught.
2042 info catch: Lists all exceptions which may be caught in the
2043 current stack frame.
2046 * Minor command changes
2048 The command ``call func (arg, arg, ...)'' now acts like the print
2049 command, except it does not print or save a value if the function's result
2050 is void. This is similar to dbx usage.
2052 The ``up'' and ``down'' commands now always print the frame they end up
2053 at; ``up-silently'' and `down-silently'' can be used in scripts to change
2054 frames without printing.
2056 * New directory command
2058 'dir' now adds directories to the FRONT of the source search path.
2059 The path starts off empty. Source files that contain debug information
2060 about the directory in which they were compiled can be found even
2061 with an empty path; Sun CC and GCC include this information. If GDB can't
2062 find your source file in the current directory, type "dir .".
2064 * Configuring GDB for compilation
2066 For normal use, type ``./configure host''. See README or gdb.texinfo
2069 GDB now handles cross debugging. If you are remotely debugging between
2070 two different machines, type ``./configure host -target=targ''.
2071 Host is the machine where GDB will run; targ is the machine
2072 where the program that you are debugging will run.
projects / external / binutils.git / blob