1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 5.0:
6 * New native configurations
8 Alpha FreeBSD alpha*-*-freebsd*
9 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
10 MIPS Linux mips*-*-linux*
11 MIPS SGI Irix 6.x mips*-sgi-irix6*
16 Motorola 68HC11 and 68HC12 m68hc11-elf
18 UltraSparc running Linux sparc64-*-linux*
20 * OBSOLETE configurations and files
22 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
23 Harris/CXUX m88k m88*-harris-cxux*
24 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
25 ns32k-utek-sysv* ns32k-utek-*
26 TI TMS320C80 tic80-*-*
28 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
29 PowerPC Solaris powerpcle-*-solaris*
30 PowerPC Windows NT powerpcle-*-cygwin32
31 PowerPC Netware powerpc-*-netware*
32 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
33 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
34 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
35 Apple Macintosh (MPW) host N/A
37 stuff.c (Program to stuff files into a specially prepared space in kdb)
38 kdb-start.c (Main loop for the standalone kernel debugger)
40 Configurations that have been declared obsolete in this release have
41 been commented out. Unless there is activity to revive these
42 configurations, the next release of GDB will have their sources
45 * REMOVED configurations and files
47 Altos 3068 m68*-altos-*
50 ARM RISCix arm-*-* (as host)
54 * GDB has been converted to ANS/ISO C.
56 GDB's source code has been converted to ANS/ISO C. In particular, the
57 sources are fully protoized, and rely on standard headers being
62 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
64 * The MI enabled by default.
66 The new machine oriented interface (MI) introduced in GDB 5.0 has been
67 revised and enabled by default. Packages which use GDB as a debugging
68 engine behind a UI or another front end are encouraged to switch to
69 using the GDB/MI interface, instead of the old annotations interface
70 which is now deprecated.
72 * Support for debugging Pascal programs.
74 GDB now includes support for debugging Pascal programs. The following
75 main features are supported:
77 - Pascal-specific data types such as sets;
79 - automatic recognition of Pascal sources based on file-name
82 - Pascal-style display of data types, variables, and functions;
84 - a Pascal expression parser.
86 However, some important features are not yet supported.
88 - Pascal string operations are not supported at all;
90 - there are some problems with boolean types;
92 - Pascal type hexadecimal constants are not supported
93 because they conflict with the internal variables format;
95 - support for Pascal objects and classes is not full yet;
97 - unlike Pascal, GDB is case-sensitive for symbol names.
99 * Changes in completion.
101 Commands such as `shell', `run' and `set args', which pass arguments
102 to inferior programs, now complete on file names, similar to what
103 users expect at the shell prompt.
105 Commands which accept locations, such as `disassemble', `print',
106 `breakpoint', `until', etc. now complete on filenames as well as
107 program symbols. Thus, if you type "break foob TAB", and the source
108 files linked into the programs include `foobar.c', that file name will
109 be one of the candidates for completion. However, file names are not
110 considered for completion after you typed a colon that delimits a file
111 name from a name of a function in that file, as in "break foo.c:bar".
113 `set demangle-style' completes on available demangling styles.
115 * New platform-independent commands:
117 It is now possible to define a post-hook for a command as well as a
118 hook that runs before the command. For more details, see the
119 documentation of `hookpost' in the GDB manual.
121 * Changes in GNU/Linux native debugging.
123 Attach/detach is supported for multi-threaded programs.
125 Support for SSE registers was added.
127 * Changes in MIPS configurations.
129 Multi-arch support is enabled for all MIPS configurations.
131 GDB can now be built as native debugger on SGI Irix 6.x systems for
132 debugging n32 executables. (Debugging 64-bit executables is not yet
135 * Unified support for hardware watchpoints in all x86 configurations.
137 Most (if not all) native x86 configurations support hardware-assisted
138 breakpoints and watchpoints in a unified manner. This support
139 implements debug register sharing between watchpoints, which allows to
140 put a virtually infinite number of watchpoints on the same address,
141 and also supports watching regions up to 16 bytes with several debug
144 The new maintenance command `maintenance show-debug-regs' toggles
145 debugging print-outs in functions that insert, remove, and test
146 watchpoints and hardware breakpoints.
148 * Changes in the DJGPP native configuration.
150 New command ``info dos sysinfo'' displays assorted information about
151 the CPU, OS, memory, and DPMI server.
153 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
154 display information about segment descriptors stored in GDT, LDT, and
157 New commands ``info dos pde'' and ``info dos pte'' display entries
158 from Page Directory and Page Tables (for now works with CWSDPMI only).
159 New command ``info dos address-pte'' displays the Page Table entry for
160 a given linear address.
162 GDB can now pass command lines longer than 126 characters to the
163 program being debugged (requires an update to the libdbg.a library
164 which is part of the DJGPP development kit).
166 DWARF2 debug info is now supported.
168 It is now possible to `step' and `next' through calls to `longjmp'.
170 * Changes in documentation.
172 All GDB documentation was converted to GFDL, the GNU Free
173 Documentation License.
175 Tracepoints-related commands are now fully documented in the GDB
178 TUI, the Text-mode User Interface, is now documented in the manual.
180 Tracepoints-related commands are now fully documented in the GDB
183 The "GDB Internals" manual now has an index. It also includes
184 documentation of `ui_out' functions, GDB coding standards, x86
185 hardware watchpoints, and memory region attributes.
187 * GDB's version number moved to ``version.in''
189 The Makefile variable VERSION has been replaced by the file
190 ``version.in''. People creating GDB distributions should update the
191 contents of this file.
195 GUD support is now a standard part of the EMACS distribution.
197 *** Changes in GDB 5.0:
199 * Improved support for debugging FP programs on x86 targets
201 Unified and much-improved support for debugging floating-point
202 programs on all x86 targets. In particular, ``info float'' now
203 displays the FP registers in the same format on all x86 targets, with
204 greater level of detail.
206 * Improvements and bugfixes in hardware-assisted watchpoints
208 It is now possible to watch array elements, struct members, and
209 bitfields with hardware-assisted watchpoints. Data-read watchpoints
210 on x86 targets no longer erroneously trigger when the address is
213 * Improvements in the native DJGPP version of GDB
215 The distribution now includes all the scripts and auxiliary files
216 necessary to build the native DJGPP version on MS-DOS/MS-Windows
217 machines ``out of the box''.
219 The DJGPP version can now debug programs that use signals. It is
220 possible to catch signals that happened in the debuggee, deliver
221 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
222 would kill the program being debugged.) Programs that hook hardware
223 interrupts (keyboard, timer, etc.) can also be debugged.
225 It is now possible to debug DJGPP programs that redirect their
226 standard handles or switch them to raw (as opposed to cooked) mode, or
227 even close them. The command ``run < foo > bar'' works as expected,
228 and ``info terminal'' reports useful information about the debuggee's
229 terminal, including raw/cooked mode, redirection, etc.
231 The DJGPP version now uses termios functions for console I/O, which
232 enables debugging graphics programs. Interrupting GDB with Ctrl-C
235 DOS-style file names with drive letters are now fully supported by
238 It is now possible to debug DJGPP programs that switch their working
239 directory. It is also possible to rerun the debuggee any number of
240 times without restarting GDB; thus, you can use the same setup,
241 breakpoints, etc. for many debugging sessions.
243 * New native configurations
245 ARM GNU/Linux arm*-*-linux*
246 PowerPC GNU/Linux powerpc-*-linux*
250 Motorola MCore mcore-*-*
251 x86 VxWorks i[3456]86-*-vxworks*
252 PowerPC VxWorks powerpc-*-vxworks*
253 TI TMS320C80 tic80-*-*
255 * OBSOLETE configurations
257 Altos 3068 m68*-altos-*
258 Convex c1-*-*, c2-*-*
260 ARM RISCix arm-*-* (as host)
263 Configurations that have been declared obsolete will be commented out,
264 but the code will be left in place. If there is no activity to revive
265 these configurations before the next release of GDB, the sources will
266 be permanently REMOVED.
268 * Gould support removed
270 Support for the Gould PowerNode and NP1 has been removed.
272 * New features for SVR4
274 On SVR4 native platforms (such as Solaris), if you attach to a process
275 without first loading a symbol file, GDB will now attempt to locate and
276 load symbols from the running process's executable file.
278 * Many C++ enhancements
280 C++ support has been greatly improved. Overload resolution now works properly
281 in almost all cases. RTTI support is on the way.
283 * Remote targets can connect to a sub-program
285 A popen(3) style serial-device has been added. This device starts a
286 sub-process (such as a stand-alone simulator) and then communicates
287 with that. The sub-program to run is specified using the syntax
288 ``|<program> <args>'' vis:
290 (gdb) set remotedebug 1
291 (gdb) target extended-remote |mn10300-elf-sim program-args
293 * MIPS 64 remote protocol
295 A long standing bug in the mips64 remote protocol where by GDB
296 expected certain 32 bit registers (ex SR) to be transfered as 32
297 instead of 64 bits has been fixed.
299 The command ``set remote-mips64-transfers-32bit-regs on'' has been
300 added to provide backward compatibility with older versions of GDB.
302 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
304 The command ``set remotebinarydownload'' command has been replaced by
305 ``set remote X-packet''. Other commands in ``set remote'' family
306 include ``set remote P-packet''.
308 * Breakpoint commands accept ranges.
310 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
311 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
312 ``tracepoint passcount'' also accepts a range of tracepoints.
314 * ``apropos'' command added.
316 The ``apropos'' command searches through command names and
317 documentation strings, printing out matches, making it much easier to
318 try to find a command that does what you are looking for.
322 A new machine oriented interface (MI) has been added to GDB. This
323 interface is designed for debug environments running GDB as a separate
324 process. This is part of the long term libGDB project. See the
325 "GDB/MI" chapter of the GDB manual for further information. It can be
326 enabled by configuring with:
328 .../configure --enable-gdbmi
330 *** Changes in GDB-4.18:
332 * New native configurations
334 HP-UX 10.20 hppa*-*-hpux10.20
335 HP-UX 11.x hppa*-*-hpux11.0*
336 M68K Linux m68*-*-linux*
340 Fujitsu FR30 fr30-*-elf*
341 Intel StrongARM strongarm-*-*
342 Mitsubishi D30V d30v-*-*
344 * OBSOLETE configurations
346 Gould PowerNode, NP1 np1-*-*, pn-*-*
348 Configurations that have been declared obsolete will be commented out,
349 but the code will be left in place. If there is no activity to revive
350 these configurations before the next release of GDB, the sources will
351 be permanently REMOVED.
355 As a compatibility experiment, GDB's source files buildsym.h and
356 buildsym.c have been converted to pure standard C, no longer
357 containing any K&R compatibility code. We believe that all systems in
358 use today either come with a standard C compiler, or have a GCC port
359 available. If this is not true, please report the affected
360 configuration to bug-gdb@gnu.org immediately. See the README file for
361 information about getting a standard C compiler if you don't have one
366 GDB now uses readline 2.2.
368 * set extension-language
370 You can now control the mapping between filename extensions and source
371 languages by using the `set extension-language' command. For instance,
372 you can ask GDB to treat .c files as C++ by saying
373 set extension-language .c c++
374 The command `info extensions' lists all of the recognized extensions
375 and their associated languages.
377 * Setting processor type for PowerPC and RS/6000
379 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
380 you can use the `set processor' command to specify what variant of the
381 PowerPC family you are debugging. The command
385 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
386 following PowerPC and RS6000 variants:
388 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
389 rs6000 IBM RS6000 ("POWER") architecture, user-level view
391 403GC IBM PowerPC 403GC
392 505 Motorola PowerPC 505
393 860 Motorola PowerPC 860 or 850
394 601 Motorola PowerPC 601
395 602 Motorola PowerPC 602
396 603 Motorola/IBM PowerPC 603 or 603e
397 604 Motorola PowerPC 604 or 604e
398 750 Motorola/IBM PowerPC 750 or 750
400 At the moment, this command just tells GDB what to name the
401 special-purpose processor registers. Since almost all the affected
402 registers are inaccessible to user-level programs, this command is
403 only useful for remote debugging in its present form.
407 Thanks to a major code donation from Hewlett-Packard, GDB now has much
408 more extensive support for HP-UX. Added features include shared
409 library support, kernel threads and hardware watchpoints for 11.00,
410 support for HP's ANSI C and C++ compilers, and a compatibility mode
411 for xdb and dbx commands.
415 HP's donation includes the new concept of catchpoints, which is a
416 generalization of the old catch command. On HP-UX, it is now possible
417 to catch exec, fork, and vfork, as well as library loading.
419 This means that the existing catch command has changed; its first
420 argument now specifies the type of catch to be set up. See the
421 output of "help catch" for a list of catchpoint types.
423 * Debugging across forks
425 On HP-UX, you can choose which process to debug when a fork() happens
430 HP has donated a curses-based terminal user interface (TUI). To get
431 it, build with --enable-tui. Although this can be enabled for any
432 configuration, at present it only works for native HP debugging.
434 * GDB remote protocol additions
436 A new protocol packet 'X' that writes binary data is now available.
437 Default behavior is to try 'X', then drop back to 'M' if the stub
438 fails to respond. The settable variable `remotebinarydownload'
439 allows explicit control over the use of 'X'.
441 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
442 full 64-bit address. The command
444 set remoteaddresssize 32
446 can be used to revert to the old behaviour. For existing remote stubs
447 the change should not be noticed, as the additional address information
450 In order to assist in debugging stubs, you may use the maintenance
451 command `packet' to send any text string to the stub. For instance,
453 maint packet heythere
455 sends the packet "$heythere#<checksum>". Note that it is very easy to
456 disrupt a debugging session by sending the wrong packet at the wrong
459 The compare-sections command allows you to compare section data on the
460 target to what is in the executable file without uploading or
461 downloading, by comparing CRC checksums.
463 * Tracing can collect general expressions
465 You may now collect general expressions at tracepoints. This requires
466 further additions to the target-side stub; see tracepoint.c and
467 doc/agentexpr.texi for further details.
469 * mask-address variable for Mips
471 For Mips targets, you may control the zeroing of the upper 32 bits of
472 a 64-bit address by entering `set mask-address on'. This is mainly
473 of interest to users of embedded R4xxx and R5xxx processors.
475 * Higher serial baud rates
477 GDB's serial code now allows you to specify baud rates 57600, 115200,
478 230400, and 460800 baud. (Note that your host system may not be able
479 to achieve all of these rates.)
483 The i960 configuration now includes an initial implementation of a
484 builtin simulator, contributed by Jim Wilson.
487 *** Changes in GDB-4.17:
489 * New native configurations
491 Alpha GNU/Linux alpha*-*-linux*
492 Unixware 2.x i[3456]86-unixware2*
493 Irix 6.x mips*-sgi-irix6*
494 PowerPC GNU/Linux powerpc-*-linux*
495 PowerPC Solaris powerpcle-*-solaris*
496 Sparc GNU/Linux sparc-*-linux*
497 Motorola sysV68 R3V7.1 m68k-motorola-sysv
501 Argonaut Risc Chip (ARC) arc-*-*
502 Hitachi H8/300S h8300*-*-*
503 Matsushita MN10200 w/simulator mn10200-*-*
504 Matsushita MN10300 w/simulator mn10300-*-*
505 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
506 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
507 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
508 Mitsubishi D10V w/simulator d10v-*-*
509 Mitsubishi M32R/D w/simulator m32r-*-elf*
510 Tsqware Sparclet sparclet-*-*
511 NEC V850 w/simulator v850-*-*
513 * New debugging protocols
515 ARM with RDI protocol arm*-*-*
516 M68K with dBUG monitor m68*-*-{aout,coff,elf}
517 DDB and LSI variants of PMON protocol mips*-*-*
518 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
519 PowerPC with SDS protocol powerpc{,le}-*-eabi
520 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
524 All configurations can now understand and use the DWARF 2 debugging
525 format. The choice is automatic, if the symbol file contains DWARF 2
530 GDB now includes basic Java language support. This support is
531 only useful with Java compilers that produce native machine code.
533 * solib-absolute-prefix and solib-search-path
535 For SunOS and SVR4 shared libraries, you may now set the prefix for
536 loading absolute shared library symbol files, and the search path for
537 locating non-absolute shared library symbol files.
539 * Live range splitting
541 GDB can now effectively debug code for which GCC has performed live
542 range splitting as part of its optimization. See gdb/doc/LRS for
543 more details on the expected format of the stabs information.
547 GDB's support for the GNU Hurd, including thread debugging, has been
548 updated to work with current versions of the Hurd.
552 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
553 instruction set. ARM GDB automatically detects when Thumb
554 instructions are in use, and adjusts disassembly and backtracing
559 GDB's MIPS target configurations now handle the MIP16 16-bit
564 GDB now includes support for overlays; if an executable has been
565 linked such that multiple sections are based at the same address, GDB
566 will decide which section to use for symbolic info. You can choose to
567 control the decision manually, using overlay commands, or implement
568 additional target-side support and use "overlay load-target" to bring
569 in the overlay mapping. Do "help overlay" for more detail.
573 The command "info symbol <address>" displays information about
574 the symbol at the specified address.
578 The standard remote protocol now includes an extension that allows
579 asynchronous collection and display of trace data. This requires
580 extensive support in the target-side debugging stub. Tracing mode
581 includes a new interaction mode in GDB and new commands: see the
582 file tracepoint.c for more details.
586 Configurations for embedded MIPS now include a simulator contributed
587 by Cygnus Solutions. The simulator supports the instruction sets
588 of most MIPS variants.
592 Sparc configurations may now include the ERC32 simulator contributed
593 by the European Space Agency. The simulator is not built into
594 Sparc targets by default; configure with --enable-sim to include it.
598 For target configurations that may include multiple variants of a
599 basic architecture (such as MIPS and SH), you may now set the
600 architecture explicitly. "set arch" sets, "info arch" lists
601 the possible architectures.
603 *** Changes in GDB-4.16:
605 * New native configurations
607 Windows 95, x86 Windows NT i[345]86-*-cygwin32
608 M68K NetBSD m68k-*-netbsd*
609 PowerPC AIX 4.x powerpc-*-aix*
610 PowerPC MacOS powerpc-*-macos*
611 PowerPC Windows NT powerpcle-*-cygwin32
612 RS/6000 AIX 4.x rs6000-*-aix4*
616 ARM with RDP protocol arm-*-*
617 I960 with MON960 i960-*-coff
618 MIPS VxWorks mips*-*-vxworks*
619 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
620 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
622 Matra Sparclet sparclet-*-*
626 The powerpc-eabi configuration now includes the PSIM simulator,
627 contributed by Andrew Cagney, with assistance from Mike Meissner.
628 PSIM is a very elaborate model of the PowerPC, including not only
629 basic instruction set execution, but also details of execution unit
630 performance and I/O hardware. See sim/ppc/README for more details.
634 GDB now works with Solaris 2.5.
636 * Windows 95/NT native
638 GDB will now work as a native debugger on Windows 95 and Windows NT.
639 To build it from source, you must use the "gnu-win32" environment,
640 which uses a DLL to emulate enough of Unix to run the GNU tools.
641 Further information, binaries, and sources are available at
642 ftp.cygnus.com, under pub/gnu-win32.
644 * dont-repeat command
646 If a user-defined command includes the command `dont-repeat', then the
647 command will not be repeated if the user just types return. This is
648 useful if the command is time-consuming to run, so that accidental
649 extra keystrokes don't run the same command many times.
651 * Send break instead of ^C
653 The standard remote protocol now includes an option to send a break
654 rather than a ^C to the target in order to interrupt it. By default,
655 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
657 * Remote protocol timeout
659 The standard remote protocol includes a new variable `remotetimeout'
660 that allows you to set the number of seconds before GDB gives up trying
661 to read from the target. The default value is 2.
663 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
665 By default GDB will automatically keep track of objects as they are
666 loaded and unloaded by the dynamic linker. By using the command `set
667 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
668 when shared library events occur, thus allowing you to set breakpoints
669 in shared libraries which are explicitly loaded by the inferior.
671 Note this feature does not work on hpux8. On hpux9 you must link
672 /usr/lib/end.o into your program. This feature should work
673 automatically on hpux10.
675 * Irix 5.x hardware watchpoint support
677 Irix 5 configurations now support the use of hardware watchpoints.
679 * Mips protocol "SYN garbage limit"
681 When debugging a Mips target using the `target mips' protocol, you
682 may set the number of characters that GDB will ignore by setting
683 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
684 every character. The default value is 1050.
686 * Recording and replaying remote debug sessions
688 If you set `remotelogfile' to the name of a file, gdb will write to it
689 a recording of a remote debug session. This recording may then be
690 replayed back to gdb using "gdbreplay". See gdbserver/README for
691 details. This is useful when you have a problem with GDB while doing
692 remote debugging; you can make a recording of the session and send it
693 to someone else, who can then recreate the problem.
695 * Speedups for remote debugging
697 GDB includes speedups for downloading and stepping MIPS systems using
698 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
699 and more efficient S-record downloading.
701 * Memory use reductions and statistics collection
703 GDB now uses less memory and reports statistics about memory usage.
704 Try the `maint print statistics' command, for example.
706 *** Changes in GDB-4.15:
710 The symbol reader for AIX GDB now uses partial symbol tables. This
711 can greatly improve startup time, especially for large executables.
713 * Remote targets use caching
715 Remote targets now use a data cache to speed up communication with the
716 remote side. The data cache could lead to incorrect results because
717 it doesn't know about volatile variables, thus making it impossible to
718 debug targets which use memory mapped I/O devices. `set remotecache
719 off' turns the the data cache off.
721 * Remote targets may have threads
723 The standard remote protocol now includes support for multiple threads
724 in the target system, using new protocol commands 'H' and 'T'. See
725 gdb/remote.c for details.
729 If GDB is configured with `--enable-netrom', then it will include
730 support for the NetROM ROM emulator from XLNT Designs. The NetROM
731 acts as though it is a bank of ROM on the target board, but you can
732 write into it over the network. GDB's support consists only of
733 support for fast loading into the emulated ROM; to debug, you must use
734 another protocol, such as standard remote protocol. The usual
735 sequence is something like
737 target nrom <netrom-hostname>
739 target remote <netrom-hostname>:1235
743 GDB now includes support for the Apple Macintosh, as a host only. It
744 may be run as either an MPW tool or as a standalone application, and
745 it can debug through the serial port. All the usual GDB commands are
746 available, but to the target command, you must supply "serial" as the
747 device type instead of "/dev/ttyXX". See mpw-README in the main
748 directory for more information on how to build. The MPW configuration
749 scripts */mpw-config.in support only a few targets, and only the
750 mips-idt-ecoff target has been tested.
754 GDB configuration now uses autoconf. This is not user-visible,
755 but does simplify configuration and building.
759 GDB now supports hpux10.
761 *** Changes in GDB-4.14:
763 * New native configurations
765 x86 FreeBSD i[345]86-*-freebsd
766 x86 NetBSD i[345]86-*-netbsd
767 NS32k NetBSD ns32k-*-netbsd
768 Sparc NetBSD sparc-*-netbsd
772 A29K VxWorks a29k-*-vxworks
773 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
774 CPU32 EST-300 emulator m68*-*-est*
775 PowerPC ELF powerpc-*-elf
778 * Alpha OSF/1 support for procfs
780 GDB now supports procfs under OSF/1-2.x and higher, which makes it
781 possible to attach to running processes. As the mounting of the /proc
782 filesystem is optional on the Alpha, GDB automatically determines
783 the availability of /proc during startup. This can lead to problems
784 if /proc is unmounted after GDB has been started.
786 * Arguments to user-defined commands
788 User commands may accept up to 10 arguments separated by whitespace.
789 Arguments are accessed within the user command via $arg0..$arg9. A
792 print $arg0 + $arg1 + $arg2
794 To execute the command use:
797 Defines the command "adder" which prints the sum of its three arguments.
798 Note the arguments are text substitutions, so they may reference variables,
799 use complex expressions, or even perform inferior function calls.
801 * New `if' and `while' commands
803 This makes it possible to write more sophisticated user-defined
804 commands. Both commands take a single argument, which is the
805 expression to evaluate, and must be followed by the commands to
806 execute, one per line, if the expression is nonzero, the list being
807 terminated by the word `end'. The `if' command list may include an
808 `else' word, which causes the following commands to be executed only
809 if the expression is zero.
811 * Fortran source language mode
813 GDB now includes partial support for Fortran 77. It will recognize
814 Fortran programs and can evaluate a subset of Fortran expressions, but
815 variables and functions may not be handled correctly. GDB will work
816 with G77, but does not yet know much about symbols emitted by other
819 * Better HPUX support
821 Most debugging facilities now work on dynamic executables for HPPAs
822 running hpux9 or later. You can attach to running dynamically linked
823 processes, but by default the dynamic libraries will be read-only, so
824 for instance you won't be able to put breakpoints in them. To change
825 that behavior do the following before running the program:
831 This will cause the libraries to be mapped private and read-write.
832 To revert to the normal behavior, do this:
838 You cannot set breakpoints or examine data in the library until after
839 the library is loaded if the function/data symbols do not have
842 GDB can now also read debug symbols produced by the HP C compiler on
843 HPPAs (sorry, no C++, Fortran or 68k support).
845 * Target byte order now dynamically selectable
847 You can choose which byte order to use with a target system, via the
848 commands "set endian big" and "set endian little", and you can see the
849 current setting by using "show endian". You can also give the command
850 "set endian auto", in which case GDB will use the byte order
851 associated with the executable. Currently, only embedded MIPS
852 configurations support dynamic selection of target byte order.
854 * New DOS host serial code
856 This version uses DPMI interrupts to handle buffered I/O, so you
857 no longer need to run asynctsr when debugging boards connected to
860 *** Changes in GDB-4.13:
862 * New "complete" command
864 This lists all the possible completions for the rest of the line, if it
865 were to be given as a command itself. This is intended for use by emacs.
867 * Trailing space optional in prompt
869 "set prompt" no longer adds a space for you after the prompt you set. This
870 allows you to set a prompt which ends in a space or one that does not.
872 * Breakpoint hit counts
874 "info break" now displays a count of the number of times the breakpoint
875 has been hit. This is especially useful in conjunction with "ignore"; you
876 can ignore a large number of breakpoint hits, look at the breakpoint info
877 to see how many times the breakpoint was hit, then run again, ignoring one
878 less than that number, and this will get you quickly to the last hit of
881 * Ability to stop printing at NULL character
883 "set print null-stop" will cause GDB to stop printing the characters of
884 an array when the first NULL is encountered. This is useful when large
885 arrays actually contain only short strings.
887 * Shared library breakpoints
889 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
890 breakpoints in shared libraries before the executable is run.
892 * Hardware watchpoints
894 There is a new hardware breakpoint for the watch command for sparclite
895 targets. See gdb/sparclite/hw_breakpoint.note.
897 Hardware watchpoints are also now supported under Linux.
901 Annotations have been added. These are for use with graphical interfaces,
902 and are still experimental. Currently only gdba.el uses these.
904 * Improved Irix 5 support
906 GDB now works properly with Irix 5.2.
908 * Improved HPPA support
910 GDB now works properly with the latest GCC and GAS.
912 * New native configurations
914 Sequent PTX4 i[34]86-sequent-ptx4
915 HPPA running OSF/1 hppa*-*-osf*
916 Atari TT running SVR4 m68*-*-sysv4*
917 RS/6000 LynxOS rs6000-*-lynxos*
921 OS/9000 i[34]86-*-os9k
922 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
925 * Hitachi SH7000 and E7000-PC ICE support
927 There is now support for communicating with the Hitachi E7000-PC ICE.
928 This is available automatically when GDB is configured for the SH.
932 As usual, a variety of small fixes and improvements, both generic
933 and configuration-specific. See the ChangeLog for more detail.
935 *** Changes in GDB-4.12:
937 * Irix 5 is now supported
941 GDB-4.12 on the HPPA has a number of changes which make it unable
942 to debug the output from the currently released versions of GCC and
943 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
944 of GCC and GAS, versions of these tools designed to work with GDB-4.12
945 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
948 *** Changes in GDB-4.11:
950 * User visible changes:
954 The "set remotedebug" option is now consistent between the mips remote
955 target, remote targets using the gdb-specific protocol, UDI (AMD's
956 debug protocol for the 29k) and the 88k bug monitor. It is now an
957 integer specifying a debug level (normally 0 or 1, but 2 means more
958 debugging info for the mips target).
960 * DEC Alpha native support
962 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
963 debug info, but GDB works fairly well with the DEC compiler and should
964 work with a future GCC release. See the README file for a few
965 Alpha-specific notes.
967 * Preliminary thread implementation
969 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
971 * LynxOS native and target support for 386
973 This release has been hosted on LynxOS 2.2, and also can be configured
974 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
977 * Improvements in C++ mangling/demangling.
979 This release has much better g++ debugging, specifically in name
980 mangling/demangling, virtual function calls, print virtual table,
981 call methods, ...etc.
983 *** Changes in GDB-4.10:
985 * User visible changes:
987 Remote debugging using the GDB-specific (`target remote') protocol now
988 supports the `load' command. This is only useful if you have some
989 other way of getting the stub to the target system, and you can put it
990 somewhere in memory where it won't get clobbered by the download.
992 Filename completion now works.
994 When run under emacs mode, the "info line" command now causes the
995 arrow to point to the line specified. Also, "info line" prints
996 addresses in symbolic form (as well as hex).
998 All vxworks based targets now support a user settable option, called
999 vxworks-timeout. This option represents the number of seconds gdb
1000 should wait for responses to rpc's. You might want to use this if
1001 your vxworks target is, perhaps, a slow software simulator or happens
1002 to be on the far side of a thin network line.
1006 This release contains support for using a DEC alpha as a GDB host for
1007 cross debugging. Native alpha debugging is not supported yet.
1010 *** Changes in GDB-4.9:
1014 This is the first GDB release which is accompanied by a matching testsuite.
1015 The testsuite requires installation of dejagnu, which should be available
1016 via ftp from most sites that carry GNU software.
1020 'Cfront' style demangling has had its name changed to 'ARM' style, to
1021 emphasize that it was written from the specifications in the C++ Annotated
1022 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
1023 disclaimers, it still generated too much confusion with users attempting to
1024 use gdb with AT&T cfront.
1028 GDB now uses a standard remote interface to a simulator library.
1029 So far, the library contains simulators for the Zilog Z8001/2, the
1030 Hitachi H8/300, H8/500 and Super-H.
1032 * New targets supported
1034 H8/300 simulator h8300-hitachi-hms or h8300hms
1035 H8/500 simulator h8500-hitachi-hms or h8500hms
1036 SH simulator sh-hitachi-hms or sh
1037 Z8000 simulator z8k-zilog-none or z8ksim
1038 IDT MIPS board over serial line mips-idt-ecoff
1040 Cross-debugging to GO32 targets is supported. It requires a custom
1041 version of the i386-stub.c module which is integrated with the
1042 GO32 memory extender.
1044 * New remote protocols
1046 MIPS remote debugging protocol.
1048 * New source languages supported
1050 This version includes preliminary support for Chill, a Pascal like language
1051 used by telecommunications companies. Chill support is also being integrated
1052 into the GNU compiler, but we don't know when it will be publically available.
1055 *** Changes in GDB-4.8:
1057 * HP Precision Architecture supported
1059 GDB now supports HP PA-RISC machines running HPUX. A preliminary
1060 version of this support was available as a set of patches from the
1061 University of Utah. GDB does not support debugging of programs
1062 compiled with the HP compiler, because HP will not document their file
1063 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
1064 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
1066 Many problems in the preliminary version have been fixed.
1068 * Faster and better demangling
1070 We have improved template demangling and fixed numerous bugs in the GNU style
1071 demangler. It can now handle type modifiers such as `static' or `const'. Wide
1072 character types (wchar_t) are now supported. Demangling of each symbol is now
1073 only done once, and is cached when the symbol table for a file is read in.
1074 This results in a small increase in memory usage for C programs, a moderate
1075 increase in memory usage for C++ programs, and a fantastic speedup in
1078 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
1079 from the specifications in the Annotated Reference Manual, which AT&T's
1080 compiler does not actually implement.
1082 * G++ multiple inheritance compiler problem
1084 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
1085 inheritance lattices was reworked to properly discover ambiguities. We
1086 recently found an example which causes this new algorithm to fail in a
1087 very subtle way, producing bad debug information for those classes.
1088 The file 'gcc.patch' (in this directory) can be applied to gcc to
1089 circumvent the problem. A future GCC release will contain a complete
1092 The previous G++ debug info problem (mentioned below for the gdb-4.7
1093 release) is fixed in gcc version 2.3.2.
1095 * Improved configure script
1097 The `configure' script will now attempt to guess your system type if
1098 you don't supply a host system type. The old scheme of supplying a
1099 host system triplet is preferable over using this. All the magic is
1100 done in the new `config.guess' script. Examine it for details.
1102 We have also brought our configure script much more in line with the FSF's
1103 version. It now supports the --with-xxx options. In particular,
1104 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
1105 The resulting GDB will not be able to read arbitrary object file formats --
1106 only the format ``expected'' to be used on the configured target system.
1107 We hope to make this the default in a future release.
1109 * Documentation improvements
1111 There's new internal documentation on how to modify GDB, and how to
1112 produce clean changes to the code. We implore people to read it
1113 before submitting changes.
1115 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
1116 M4 macros. The new texinfo.tex is provided in this release. Pre-built
1117 `info' files are also provided. To build `info' files from scratch,
1118 you will need the latest `makeinfo' release, which will be available in
1119 a future texinfo-X.Y release.
1121 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
1122 We're not sure exactly which versions have this problem, but it has
1123 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
1124 or better. If that isn't possible, there is a patch in
1125 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
1126 around this problem.
1130 GDB now supports array constants that can be used in expressions typed in by
1131 the user. The syntax is `{element, element, ...}'. Ie: you can now type
1132 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
1135 The new directory `gdb/sparclite' contains a program that demonstrates
1136 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
1138 * New native hosts supported
1140 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
1141 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
1143 * New targets supported
1145 AMD 29k family via UDI a29k-amd-udi or udi29k
1147 * New file formats supported
1149 BFD now supports reading HP/PA-RISC executables (SOM file format?),
1150 HPUX core files, and SCO 3.2v2 core files.
1154 Attaching to processes now works again; thanks for the many bug reports.
1156 We have also stomped on a bunch of core dumps caused by
1157 printf_filtered("%s") problems.
1159 We eliminated a copyright problem on the rpc and ptrace header files
1160 for VxWorks, which was discovered at the last minute during the 4.7
1161 release. You should now be able to build a VxWorks GDB.
1163 You can now interrupt gdb while an attached process is running. This
1164 will cause the attached process to stop, and give control back to GDB.
1166 We fixed problems caused by using too many file descriptors
1167 for reading symbols from object files and libraries. This was
1168 especially a problem for programs that used many (~100) shared
1171 The `step' command now only enters a subroutine if there is line number
1172 information for the subroutine. Otherwise it acts like the `next'
1173 command. Previously, `step' would enter subroutines if there was
1174 any debugging information about the routine. This avoids problems
1175 when using `cc -g1' on MIPS machines.
1177 * Internal improvements
1179 GDB's internal interfaces have been improved to make it easier to support
1180 debugging of multiple languages in the future.
1182 GDB now uses a common structure for symbol information internally.
1183 Minimal symbols (derived from linkage symbols in object files), partial
1184 symbols (from a quick scan of debug information), and full symbols
1185 contain a common subset of information, making it easier to write
1186 shared code that handles any of them.
1188 * New command line options
1190 We now accept --silent as an alias for --quiet.
1194 The memory-mapped-malloc library is now licensed under the GNU Library
1195 General Public License.
1197 *** Changes in GDB-4.7:
1199 * Host/native/target split
1201 GDB has had some major internal surgery to untangle the support for
1202 hosts and remote targets. Now, when you configure GDB for a remote
1203 target, it will no longer load in all of the support for debugging
1204 local programs on the host. When fully completed and tested, this will
1205 ensure that arbitrary host/target combinations are possible.
1207 The primary conceptual shift is to separate the non-portable code in
1208 GDB into three categories. Host specific code is required any time GDB
1209 is compiled on that host, regardless of the target. Target specific
1210 code relates to the peculiarities of the target, but can be compiled on
1211 any host. Native specific code is everything else: it can only be
1212 built when the host and target are the same system. Child process
1213 handling and core file support are two common `native' examples.
1215 GDB's use of /proc for controlling Unix child processes is now cleaner.
1216 It has been split out into a single module under the `target_ops' vector,
1217 plus two native-dependent functions for each system that uses /proc.
1219 * New hosts supported
1221 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
1222 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1223 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
1225 * New targets supported
1227 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1228 68030 and CPU32 m68030-*-*, m68332-*-*
1230 * New native hosts supported
1232 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1233 (386bsd is not well tested yet)
1234 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
1236 * New file formats supported
1238 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
1239 supports reading of `a.out.adobe' object files, which are an a.out
1240 format extended with minimal information about multiple sections.
1244 `show copying' is the same as the old `info copying'.
1245 `show warranty' is the same as `info warrantee'.
1246 These were renamed for consistency. The old commands continue to work.
1248 `info handle' is a new alias for `info signals'.
1250 You can now define pre-command hooks, which attach arbitrary command
1251 scripts to any command. The commands in the hook will be executed
1252 prior to the user's command. You can also create a hook which will be
1253 executed whenever the program stops. See gdb.texinfo.
1257 We now deal with Cfront style name mangling, and can even extract type
1258 info from mangled symbols. GDB can automatically figure out which
1259 symbol mangling style your C++ compiler uses.
1261 Calling of methods and virtual functions has been improved as well.
1265 The crash that occured when debugging Sun Ansi-C compiled binaries is
1266 fixed. This was due to mishandling of the extra N_SO stabs output
1269 We also finally got Ultrix 4.2 running in house, and fixed core file
1270 support, with help from a dozen people on the net.
1272 John M. Farrell discovered that the reason that single-stepping was so
1273 slow on all of the Mips based platforms (primarily SGI and DEC) was
1274 that we were trying to demangle and lookup a symbol used for internal
1275 purposes on every instruction that was being stepped through. Changing
1276 the name of that symbol so that it couldn't be mistaken for a C++
1277 mangled symbol sped things up a great deal.
1279 Rich Pixley sped up symbol lookups in general by getting much smarter
1280 about when C++ symbol mangling is necessary. This should make symbol
1281 completion (TAB on the command line) much faster. It's not as fast as
1282 we'd like, but it's significantly faster than gdb-4.6.
1286 A new user controllable variable 'call_scratch_address' can
1287 specify the location of a scratch area to be used when GDB
1288 calls a function in the target. This is necessary because the
1289 usual method of putting the scratch area on the stack does not work
1290 in systems that have separate instruction and data spaces.
1292 We integrated changes to support the 29k UDI (Universal Debugger
1293 Interface), but discovered at the last minute that we didn't have all
1294 of the appropriate copyright paperwork. We are working with AMD to
1295 resolve this, and hope to have it available soon.
1299 We have sped up the remote serial line protocol, especially for targets
1300 with lots of registers. It now supports a new `expedited status' ('T')
1301 message which can be used in place of the existing 'S' status message.
1302 This allows the remote stub to send only the registers that GDB
1303 needs to make a quick decision about single-stepping or conditional
1304 breakpoints, eliminating the need to fetch the entire register set for
1305 each instruction being stepped through.
1307 The GDB remote serial protocol now implements a write-through cache for
1308 registers, only re-reading the registers if the target has run.
1310 There is also a new remote serial stub for SPARC processors. You can
1311 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
1312 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
1313 processor with a serial port.
1317 Configure.in files have become much easier to read and modify. A new
1318 `table driven' format makes it more obvious what configurations are
1319 supported, and what files each one uses.
1323 There is a new opcodes library which will eventually contain all of the
1324 disassembly routines and opcode tables. At present, it only contains
1325 Sparc and Z8000 routines. This will allow the assembler, debugger, and
1326 disassembler (binutils/objdump) to share these routines.
1328 The libiberty library is now copylefted under the GNU Library General
1329 Public License. This allows more liberal use, and was done so libg++
1330 can use it. This makes no difference to GDB, since the Library License
1331 grants all the rights from the General Public License.
1335 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
1336 reference to the stabs symbol info used by the debugger. It is (as far
1337 as we know) the only published document on this fascinating topic. We
1338 encourage you to read it, compare it to the stabs information on your
1339 system, and send improvements on the document in general (to
1340 bug-gdb@prep.ai.mit.edu).
1342 And, of course, many bugs have been fixed.
1345 *** Changes in GDB-4.6:
1347 * Better support for C++ function names
1349 GDB now accepts as input the "demangled form" of C++ overloaded function
1350 names and member function names, and can do command completion on such names
1351 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
1352 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
1353 Make use of command completion, it is your friend.
1355 GDB also now accepts a variety of C++ mangled symbol formats. They are
1356 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
1357 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
1358 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
1359 for the list of formats.
1361 * G++ symbol mangling problem
1363 Recent versions of gcc have a bug in how they emit debugging information for
1364 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
1365 directory) can be applied to gcc to fix the problem. Alternatively, if you
1366 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
1367 usual symptom is difficulty with setting breakpoints on methods. GDB complains
1368 about the method being non-existent. (We believe that version 2.2.2 of GCC has
1371 * New 'maintenance' command
1373 All of the commands related to hacking GDB internals have been moved out of
1374 the main command set, and now live behind the 'maintenance' command. This
1375 can also be abbreviated as 'mt'. The following changes were made:
1377 dump-me -> maintenance dump-me
1378 info all-breakpoints -> maintenance info breakpoints
1379 printmsyms -> maintenance print msyms
1380 printobjfiles -> maintenance print objfiles
1381 printpsyms -> maintenance print psymbols
1382 printsyms -> maintenance print symbols
1384 The following commands are new:
1386 maintenance demangle Call internal GDB demangler routine to
1387 demangle a C++ link name and prints the result.
1388 maintenance print type Print a type chain for a given symbol
1390 * Change to .gdbinit file processing
1392 We now read the $HOME/.gdbinit file before processing the argv arguments
1393 (e.g. reading symbol files or core files). This allows global parameters to
1394 be set, which will apply during the symbol reading. The ./.gdbinit is still
1395 read after argv processing.
1397 * New hosts supported
1399 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
1401 Linux support i386-unknown-linux or linux
1403 We are also including code to support the HP/PA running BSD and HPUX. This
1404 is almost guaranteed not to work, as we didn't have time to test or build it
1405 for this release. We are including it so that the more adventurous (or
1406 masochistic) of you can play with it. We also had major problems with the
1407 fact that the compiler that we got from HP doesn't support the -g option.
1410 * New targets supported
1412 Hitachi H8/300 h8300-hitachi-hms or h8300hms
1414 * More smarts about finding #include files
1416 GDB now remembers the compilation directory for all include files, and for
1417 all files from which C is generated (like yacc and lex sources). This
1418 greatly improves GDB's ability to find yacc/lex sources, and include files,
1419 especially if you are debugging your program from a directory different from
1420 the one that contains your sources.
1422 We also fixed a bug which caused difficulty with listing and setting
1423 breakpoints in include files which contain C code. (In the past, you had to
1424 try twice in order to list an include file that you hadn't looked at before.)
1426 * Interesting infernals change
1428 GDB now deals with arbitrary numbers of sections, where the symbols for each
1429 section must be relocated relative to that section's landing place in the
1430 target's address space. This work was needed to support ELF with embedded
1431 stabs used by Solaris-2.0.
1433 * Bug fixes (of course!)
1435 There have been loads of fixes for the following things:
1436 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
1437 i960, stabs, DOS(GO32), procfs, etc...
1439 See the ChangeLog for details.
1441 *** Changes in GDB-4.5:
1443 * New machines supported (host and target)
1445 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
1447 SGI Irix-4.x mips-sgi-irix4 or iris4
1449 * New malloc package
1451 GDB now uses a new memory manager called mmalloc, based on gmalloc.
1452 Mmalloc is capable of handling mutiple heaps of memory. It is also
1453 capable of saving a heap to a file, and then mapping it back in later.
1454 This can be used to greatly speedup the startup of GDB by using a
1455 pre-parsed symbol table which lives in a mmalloc managed heap. For
1456 more details, please read mmalloc/mmalloc.texi.
1460 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
1461 'help info proc' for details.
1463 * MIPS ecoff symbol table format
1465 The code that reads MIPS symbol table format is now supported on all hosts.
1466 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
1469 * File name changes for MS-DOS
1471 Many files in the config directories have been renamed to make it easier to
1472 support GDB on MS-DOSe systems (which have very restrictive file name
1473 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
1474 environment) is close to working but has some remaining problems. Note
1475 that debugging of DOS programs is not supported, due to limitations
1476 in the ``operating system'', but it can be used to host cross-debugging.
1478 * Cross byte order fixes
1480 Many fixes have been made to support cross debugging of Sparc and MIPS
1481 targets from hosts whose byte order differs.
1483 * New -mapped and -readnow options
1485 If memory-mapped files are available on your system through the 'mmap'
1486 system call, you can use the -mapped option on the `file' or
1487 `symbol-file' commands to cause GDB to write the symbols from your
1488 program into a reusable file. If the program you are debugging is
1489 called `/path/fred', the mapped symbol file will be `./fred.syms'.
1490 Future GDB debugging sessions will notice the presence of this file,
1491 and will quickly map in symbol information from it, rather than reading
1492 the symbol table from the executable program. Using the '-mapped'
1493 option in a GDB `file' or `symbol-file' command has the same effect as
1494 starting GDB with the '-mapped' command-line option.
1496 You can cause GDB to read the entire symbol table immediately by using
1497 the '-readnow' option with any of the commands that load symbol table
1498 information (or on the GDB command line). This makes the command
1499 slower, but makes future operations faster.
1501 The -mapped and -readnow options are typically combined in order to
1502 build a `fred.syms' file that contains complete symbol information.
1503 A simple GDB invocation to do nothing but build a `.syms' file for future
1506 gdb -batch -nx -mapped -readnow programname
1508 The `.syms' file is specific to the host machine on which GDB is run.
1509 It holds an exact image of GDB's internal symbol table. It cannot be
1510 shared across multiple host platforms.
1512 * longjmp() handling
1514 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
1515 siglongjmp() without losing control. This feature has not yet been ported to
1516 all systems. It currently works on many 386 platforms, all MIPS-based
1517 platforms (SGI, DECstation, etc), and Sun3/4.
1521 Preliminary work has been put in to support the new Solaris OS from Sun. At
1522 this time, it can control and debug processes, but it is not capable of
1527 As always, many many bug fixes. The major areas were with g++, and mipsread.
1528 People using the MIPS-based platforms should experience fewer mysterious
1529 crashes and trashed symbol tables.
1531 *** Changes in GDB-4.4:
1533 * New machines supported (host and target)
1535 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1537 BSD Reno on Vax vax-dec-bsd
1538 Ultrix on Vax vax-dec-ultrix
1540 * New machines supported (target)
1542 AMD 29000 embedded, using EBMON a29k-none-none
1546 GDB continues to improve its handling of C++. `References' work better.
1547 The demangler has also been improved, and now deals with symbols mangled as
1548 per the Annotated C++ Reference Guide.
1550 GDB also now handles `stabs' symbol information embedded in MIPS
1551 `ecoff' symbol tables. Since the ecoff format was not easily
1552 extensible to handle new languages such as C++, this appeared to be a
1553 good way to put C++ debugging info into MIPS binaries. This option
1554 will be supported in the GNU C compiler, version 2, when it is
1557 * New features for SVR4
1559 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
1560 shared libraries. Debugging dynamically linked programs should present
1561 only minor differences from debugging statically linked programs.
1563 The `info proc' command will print out information about any process
1564 on an SVR4 system (including the one you are debugging). At the moment,
1565 it prints the address mappings of the process.
1567 If you bring up GDB on another SVR4 system, please send mail to
1568 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
1570 * Better dynamic linking support in SunOS
1572 Reading symbols from shared libraries which contain debugging symbols
1573 now works properly. However, there remain issues such as automatic
1574 skipping of `transfer vector' code during function calls, which
1575 make it harder to debug code in a shared library, than to debug the
1576 same code linked statically.
1580 GDB is now using the latest `getopt' routines from the FSF. This
1581 version accepts the -- prefix for options with long names. GDB will
1582 continue to accept the old forms (-option and +option) as well.
1583 Various single letter abbreviations for options have been explicity
1584 added to the option table so that they won't get overshadowed in the
1585 future by other options that begin with the same letter.
1589 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
1590 Many assorted bugs have been handled. Many more remain to be handled.
1591 See the various ChangeLog files (primarily in gdb and bfd) for details.
1594 *** Changes in GDB-4.3:
1596 * New machines supported (host and target)
1598 Amiga 3000 running Amix m68k-cbm-svr4 or amix
1599 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
1600 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1602 * Almost SCO Unix support
1604 We had hoped to support:
1605 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1606 (except for core file support), but we discovered very late in the release
1607 that it has problems with process groups that render gdb unusable. Sorry
1608 about that. I encourage people to fix it and post the fixes.
1610 * Preliminary ELF and DWARF support
1612 GDB can read ELF object files on System V Release 4, and can handle
1613 debugging records for C, in DWARF format, in ELF files. This support
1614 is preliminary. If you bring up GDB on another SVR4 system, please
1615 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
1620 GDB now uses the latest `readline' library. One user-visible change
1621 is that two tabs will list possible command completions, which previously
1622 required typing M-? (meta-question mark, or ESC ?).
1626 The `stepi' bug that many of you noticed has been squashed.
1627 Many bugs in C++ have been handled. Many more remain to be handled.
1628 See the various ChangeLog files (primarily in gdb and bfd) for details.
1630 * State of the MIPS world (in case you wondered):
1632 GDB can understand the symbol tables emitted by the compilers
1633 supplied by most vendors of MIPS-based machines, including DEC. These
1634 symbol tables are in a format that essentially nobody else uses.
1636 Some versions of gcc come with an assembler post-processor called
1637 mips-tfile. This program is required if you want to do source-level
1638 debugging of gcc-compiled programs. I believe FSF does not ship
1639 mips-tfile with gcc version 1, but it will eventually come with gcc
1642 Debugging of g++ output remains a problem. g++ version 1.xx does not
1643 really support it at all. (If you're lucky, you should be able to get
1644 line numbers and stack traces to work, but no parameters or local
1645 variables.) With some work it should be possible to improve the
1648 When gcc version 2 is released, you will have somewhat better luck.
1649 However, even then you will get confusing results for inheritance and
1652 We will eventually provide full debugging of g++ output on
1653 DECstations. This will probably involve some kind of stabs-in-ecoff
1654 encapulation, but the details have not been worked out yet.
1657 *** Changes in GDB-4.2:
1659 * Improved configuration
1661 Only one copy of `configure' exists now, and it is not self-modifying.
1662 Porting BFD is simpler.
1666 The `step' and `next' commands now only stop at the first instruction
1667 of a source line. This prevents the multiple stops that used to occur
1668 in switch statements, for-loops, etc. `Step' continues to stop if a
1669 function that has debugging information is called within the line.
1673 Lots of small bugs fixed. More remain.
1675 * New host supported (not target)
1677 Intel 386 PC clone running Mach i386-none-mach
1680 *** Changes in GDB-4.1:
1682 * Multiple source language support
1684 GDB now has internal scaffolding to handle several source languages.
1685 It determines the type of each source file from its filename extension,
1686 and will switch expression parsing and number formatting to match the
1687 language of the function in the currently selected stack frame.
1688 You can also specifically set the language to be used, with
1689 `set language c' or `set language modula-2'.
1693 GDB now has preliminary support for the GNU Modula-2 compiler,
1694 currently under development at the State University of New York at
1695 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
1696 continue through the fall of 1991 and into 1992.
1698 Other Modula-2 compilers are currently not supported, and attempting to
1699 debug programs compiled with them will likely result in an error as the
1700 symbol table is read. Feel free to work on it, though!
1702 There are hooks in GDB for strict type checking and range checking,
1703 in the `Modula-2 philosophy', but they do not currently work.
1707 GDB can now write to executable and core files (e.g. patch
1708 a variable's value). You must turn this switch on, specify
1709 the file ("exec foo" or "core foo"), *then* modify it, e.g.
1710 by assigning a new value to a variable. Modifications take
1713 * Automatic SunOS shared library reading
1715 When you run your program, GDB automatically determines where its
1716 shared libraries (if any) have been loaded, and reads their symbols.
1717 The `share' command is no longer needed. This also works when
1718 examining core files.
1722 You can specify the number of lines that the `list' command shows.
1725 * New machines supported (host and target)
1727 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1728 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
1729 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
1731 * New hosts supported (not targets)
1733 IBM RT/PC: romp-ibm-aix or rtpc
1735 * New targets supported (not hosts)
1737 AMD 29000 embedded with COFF a29k-none-coff
1738 AMD 29000 embedded with a.out a29k-none-aout
1739 Ultracomputer remote kernel debug a29k-nyu-kern
1741 * New remote interfaces
1747 *** Changes in GDB-4.0:
1751 Wide output is wrapped at good places to make the output more readable.
1753 Gdb now supports cross-debugging from a host machine of one type to a
1754 target machine of another type. Communication with the target system
1755 is over serial lines. The ``target'' command handles connecting to the
1756 remote system; the ``load'' command will download a program into the
1757 remote system. Serial stubs for the m68k and i386 are provided. Gdb
1758 also supports debugging of realtime processes running under VxWorks,
1759 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
1760 stub on the target system.
1762 New CPUs supported include the AMD 29000 and Intel 960.
1764 GDB now reads object files and symbol tables via a ``binary file''
1765 library, which allows a single copy of GDB to debug programs of multiple
1766 object file types such as a.out and coff.
1768 There is now a GDB reference card in "doc/refcard.tex". (Make targets
1769 refcard.dvi and refcard.ps are available to format it).
1772 * Control-Variable user interface simplified
1774 All variables that control the operation of the debugger can be set
1775 by the ``set'' command, and displayed by the ``show'' command.
1777 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
1778 ``Show prompt'' produces the response:
1779 Gdb's prompt is new-gdb=>.
1781 What follows are the NEW set commands. The command ``help set'' will
1782 print a complete list of old and new set commands. ``help set FOO''
1783 will give a longer description of the variable FOO. ``show'' will show
1784 all of the variable descriptions and their current settings.
1786 confirm on/off: Enables warning questions for operations that are
1787 hard to recover from, e.g. rerunning the program while
1788 it is already running. Default is ON.
1790 editing on/off: Enables EMACS style command line editing
1791 of input. Previous lines can be recalled with
1792 control-P, the current line can be edited with control-B,
1793 you can search for commands with control-R, etc.
1796 history filename NAME: NAME is where the gdb command history
1797 will be stored. The default is .gdb_history,
1798 or the value of the environment variable
1801 history size N: The size, in commands, of the command history. The
1802 default is 256, or the value of the environment variable
1805 history save on/off: If this value is set to ON, the history file will
1806 be saved after exiting gdb. If set to OFF, the
1807 file will not be saved. The default is OFF.
1809 history expansion on/off: If this value is set to ON, then csh-like
1810 history expansion will be performed on
1811 command line input. The default is OFF.
1813 radix N: Sets the default radix for input and output. It can be set
1814 to 8, 10, or 16. Note that the argument to "radix" is interpreted
1815 in the current radix, so "set radix 10" is always a no-op.
1817 height N: This integer value is the number of lines on a page. Default
1818 is 24, the current `stty rows'' setting, or the ``li#''
1819 setting from the termcap entry matching the environment
1822 width N: This integer value is the number of characters on a line.
1823 Default is 80, the current `stty cols'' setting, or the ``co#''
1824 setting from the termcap entry matching the environment
1827 Note: ``set screensize'' is obsolete. Use ``set height'' and
1828 ``set width'' instead.
1830 print address on/off: Print memory addresses in various command displays,
1831 such as stack traces and structure values. Gdb looks
1832 more ``symbolic'' if you turn this off; it looks more
1833 ``machine level'' with it on. Default is ON.
1835 print array on/off: Prettyprint arrays. New convenient format! Default
1838 print demangle on/off: Print C++ symbols in "source" form if on,
1841 print asm-demangle on/off: Same, for assembler level printouts
1844 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
1847 * Support for Epoch Environment.
1849 The epoch environment is a version of Emacs v18 with windowing. One
1850 new command, ``inspect'', is identical to ``print'', except that if you
1851 are running in the epoch environment, the value is printed in its own
1855 * Support for Shared Libraries
1857 GDB can now debug programs and core files that use SunOS shared libraries.
1858 Symbols from a shared library cannot be referenced
1859 before the shared library has been linked with the program (this
1860 happens after you type ``run'' and before the function main() is entered).
1861 At any time after this linking (including when examining core files
1862 from dynamically linked programs), gdb reads the symbols from each
1863 shared library when you type the ``sharedlibrary'' command.
1864 It can be abbreviated ``share''.
1866 sharedlibrary REGEXP: Load shared object library symbols for files
1867 matching a unix regular expression. No argument
1868 indicates to load symbols for all shared libraries.
1870 info sharedlibrary: Status of loaded shared libraries.
1875 A watchpoint stops execution of a program whenever the value of an
1876 expression changes. Checking for this slows down execution
1877 tremendously whenever you are in the scope of the expression, but is
1878 quite useful for catching tough ``bit-spreader'' or pointer misuse
1879 problems. Some machines such as the 386 have hardware for doing this
1880 more quickly, and future versions of gdb will use this hardware.
1882 watch EXP: Set a watchpoint (breakpoint) for an expression.
1884 info watchpoints: Information about your watchpoints.
1886 delete N: Deletes watchpoint number N (same as breakpoints).
1887 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
1888 enable N: Re-enables watchpoint number N (same as breakpoints).
1891 * C++ multiple inheritance
1893 When used with a GCC version 2 compiler, GDB supports multiple inheritance
1896 * C++ exception handling
1898 Gdb now supports limited C++ exception handling. Besides the existing
1899 ability to breakpoint on an exception handler, gdb can breakpoint on
1900 the raising of an exception (before the stack is peeled back to the
1903 catch FOO: If there is a FOO exception handler in the dynamic scope,
1904 set a breakpoint to catch exceptions which may be raised there.
1905 Multiple exceptions (``catch foo bar baz'') may be caught.
1907 info catch: Lists all exceptions which may be caught in the
1908 current stack frame.
1911 * Minor command changes
1913 The command ``call func (arg, arg, ...)'' now acts like the print
1914 command, except it does not print or save a value if the function's result
1915 is void. This is similar to dbx usage.
1917 The ``up'' and ``down'' commands now always print the frame they end up
1918 at; ``up-silently'' and `down-silently'' can be used in scripts to change
1919 frames without printing.
1921 * New directory command
1923 'dir' now adds directories to the FRONT of the source search path.
1924 The path starts off empty. Source files that contain debug information
1925 about the directory in which they were compiled can be found even
1926 with an empty path; Sun CC and GCC include this information. If GDB can't
1927 find your source file in the current directory, type "dir .".
1929 * Configuring GDB for compilation
1931 For normal use, type ``./configure host''. See README or gdb.texinfo
1934 GDB now handles cross debugging. If you are remotely debugging between
1935 two different machines, type ``./configure host -target=targ''.
1936 Host is the machine where GDB will run; targ is the machine
1937 where the program that you are debugging will run.