1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 5.1:
6 * New native configurations
8 x86 OpenBSD i[3456]86-*-openbsd*
10 * REMOVED configurations and files
12 TI TMS320C80 tic80-*-*
14 PowerPC Solaris powerpcle-*-solaris*
15 PowerPC Windows NT powerpcle-*-cygwin32
16 PowerPC Netware powerpc-*-netware*
17 Harris/CXUX m88k m88*-harris-cxux*
18 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
19 ns32k-utek-sysv* ns32k-utek-*
21 * Changes to command line processing
23 The new `--args' feature can be used to specify command-line arguments
24 for the inferior from gdb's command line.
26 * Changes to key bindings
28 There is a new `operate-and-get-next' function bound to `C-o'.
30 *** Changes in GDB 5.1:
32 * New native configurations
34 Alpha FreeBSD alpha*-*-freebsd*
35 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
36 MIPS Linux mips*-*-linux*
37 MIPS SGI Irix 6.x mips*-sgi-irix6*
39 s390 and s390x Linux {s390,s390x}-*-linux*
43 Motorola 68HC11 and 68HC12 m68hc11-elf
45 UltraSparc running Linux sparc64-*-linux*
47 * OBSOLETE configurations and files
49 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
50 Harris/CXUX m88k m88*-harris-cxux*
51 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
52 ns32k-utek-sysv* ns32k-utek-*
53 TI TMS320C80 tic80-*-*
55 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
56 PowerPC Solaris powerpcle-*-solaris*
57 PowerPC Windows NT powerpcle-*-cygwin32
58 PowerPC Netware powerpc-*-netware*
59 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
60 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
61 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
62 Apple Macintosh (MPW) host N/A
64 stuff.c (Program to stuff files into a specially prepared space in kdb)
65 kdb-start.c (Main loop for the standalone kernel debugger)
67 Configurations that have been declared obsolete in this release have
68 been commented out. Unless there is activity to revive these
69 configurations, the next release of GDB will have their sources
72 * REMOVED configurations and files
74 Altos 3068 m68*-altos-*
77 ARM RISCix arm-*-* (as host)
81 * GDB has been converted to ISO C.
83 GDB's source code has been converted to ISO C. In particular, the
84 sources are fully protoized, and rely on standard headers being
89 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
91 * The MI enabled by default.
93 The new machine oriented interface (MI) introduced in GDB 5.0 has been
94 revised and enabled by default. Packages which use GDB as a debugging
95 engine behind a UI or another front end are encouraged to switch to
96 using the GDB/MI interface, instead of the old annotations interface
97 which is now deprecated.
99 * Support for debugging Pascal programs.
101 GDB now includes support for debugging Pascal programs. The following
102 main features are supported:
104 - Pascal-specific data types such as sets;
106 - automatic recognition of Pascal sources based on file-name
109 - Pascal-style display of data types, variables, and functions;
111 - a Pascal expression parser.
113 However, some important features are not yet supported.
115 - Pascal string operations are not supported at all;
117 - there are some problems with boolean types;
119 - Pascal type hexadecimal constants are not supported
120 because they conflict with the internal variables format;
122 - support for Pascal objects and classes is not full yet;
124 - unlike Pascal, GDB is case-sensitive for symbol names.
126 * Changes in completion.
128 Commands such as `shell', `run' and `set args', which pass arguments
129 to inferior programs, now complete on file names, similar to what
130 users expect at the shell prompt.
132 Commands which accept locations, such as `disassemble', `print',
133 `breakpoint', `until', etc. now complete on filenames as well as
134 program symbols. Thus, if you type "break foob TAB", and the source
135 files linked into the programs include `foobar.c', that file name will
136 be one of the candidates for completion. However, file names are not
137 considered for completion after you typed a colon that delimits a file
138 name from a name of a function in that file, as in "break foo.c:bar".
140 `set demangle-style' completes on available demangling styles.
142 * New platform-independent commands:
144 It is now possible to define a post-hook for a command as well as a
145 hook that runs before the command. For more details, see the
146 documentation of `hookpost' in the GDB manual.
148 * Changes in GNU/Linux native debugging.
150 Support for debugging multi-threaded programs has been completely
151 revised for all platforms except m68k and sparc. You can now debug as
152 many threads as your system allows you to have.
154 Attach/detach is supported for multi-threaded programs.
156 Support for SSE registers was added for x86. This doesn't work for
157 multi-threaded programs though.
159 * Changes in MIPS configurations.
161 Multi-arch support is enabled for all MIPS configurations.
163 GDB can now be built as native debugger on SGI Irix 6.x systems for
164 debugging n32 executables. (Debugging 64-bit executables is not yet
167 * Unified support for hardware watchpoints in all x86 configurations.
169 Most (if not all) native x86 configurations support hardware-assisted
170 breakpoints and watchpoints in a unified manner. This support
171 implements debug register sharing between watchpoints, which allows to
172 put a virtually infinite number of watchpoints on the same address,
173 and also supports watching regions up to 16 bytes with several debug
176 The new maintenance command `maintenance show-debug-regs' toggles
177 debugging print-outs in functions that insert, remove, and test
178 watchpoints and hardware breakpoints.
180 * Changes in the DJGPP native configuration.
182 New command ``info dos sysinfo'' displays assorted information about
183 the CPU, OS, memory, and DPMI server.
185 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
186 display information about segment descriptors stored in GDT, LDT, and
189 New commands ``info dos pde'' and ``info dos pte'' display entries
190 from Page Directory and Page Tables (for now works with CWSDPMI only).
191 New command ``info dos address-pte'' displays the Page Table entry for
192 a given linear address.
194 GDB can now pass command lines longer than 126 characters to the
195 program being debugged (requires an update to the libdbg.a library
196 which is part of the DJGPP development kit).
198 DWARF2 debug info is now supported.
200 It is now possible to `step' and `next' through calls to `longjmp'.
202 * Changes in documentation.
204 All GDB documentation was converted to GFDL, the GNU Free
205 Documentation License.
207 Tracepoints-related commands are now fully documented in the GDB
210 TUI, the Text-mode User Interface, is now documented in the manual.
212 Tracepoints-related commands are now fully documented in the GDB
215 The "GDB Internals" manual now has an index. It also includes
216 documentation of `ui_out' functions, GDB coding standards, x86
217 hardware watchpoints, and memory region attributes.
219 * GDB's version number moved to ``version.in''
221 The Makefile variable VERSION has been replaced by the file
222 ``version.in''. People creating GDB distributions should update the
223 contents of this file.
227 GUD support is now a standard part of the EMACS distribution.
229 *** Changes in GDB 5.0:
231 * Improved support for debugging FP programs on x86 targets
233 Unified and much-improved support for debugging floating-point
234 programs on all x86 targets. In particular, ``info float'' now
235 displays the FP registers in the same format on all x86 targets, with
236 greater level of detail.
238 * Improvements and bugfixes in hardware-assisted watchpoints
240 It is now possible to watch array elements, struct members, and
241 bitfields with hardware-assisted watchpoints. Data-read watchpoints
242 on x86 targets no longer erroneously trigger when the address is
245 * Improvements in the native DJGPP version of GDB
247 The distribution now includes all the scripts and auxiliary files
248 necessary to build the native DJGPP version on MS-DOS/MS-Windows
249 machines ``out of the box''.
251 The DJGPP version can now debug programs that use signals. It is
252 possible to catch signals that happened in the debuggee, deliver
253 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
254 would kill the program being debugged.) Programs that hook hardware
255 interrupts (keyboard, timer, etc.) can also be debugged.
257 It is now possible to debug DJGPP programs that redirect their
258 standard handles or switch them to raw (as opposed to cooked) mode, or
259 even close them. The command ``run < foo > bar'' works as expected,
260 and ``info terminal'' reports useful information about the debuggee's
261 terminal, including raw/cooked mode, redirection, etc.
263 The DJGPP version now uses termios functions for console I/O, which
264 enables debugging graphics programs. Interrupting GDB with Ctrl-C
267 DOS-style file names with drive letters are now fully supported by
270 It is now possible to debug DJGPP programs that switch their working
271 directory. It is also possible to rerun the debuggee any number of
272 times without restarting GDB; thus, you can use the same setup,
273 breakpoints, etc. for many debugging sessions.
275 * New native configurations
277 ARM GNU/Linux arm*-*-linux*
278 PowerPC GNU/Linux powerpc-*-linux*
282 Motorola MCore mcore-*-*
283 x86 VxWorks i[3456]86-*-vxworks*
284 PowerPC VxWorks powerpc-*-vxworks*
285 TI TMS320C80 tic80-*-*
287 * OBSOLETE configurations
289 Altos 3068 m68*-altos-*
290 Convex c1-*-*, c2-*-*
292 ARM RISCix arm-*-* (as host)
295 Configurations that have been declared obsolete will be commented out,
296 but the code will be left in place. If there is no activity to revive
297 these configurations before the next release of GDB, the sources will
298 be permanently REMOVED.
300 * Gould support removed
302 Support for the Gould PowerNode and NP1 has been removed.
304 * New features for SVR4
306 On SVR4 native platforms (such as Solaris), if you attach to a process
307 without first loading a symbol file, GDB will now attempt to locate and
308 load symbols from the running process's executable file.
310 * Many C++ enhancements
312 C++ support has been greatly improved. Overload resolution now works properly
313 in almost all cases. RTTI support is on the way.
315 * Remote targets can connect to a sub-program
317 A popen(3) style serial-device has been added. This device starts a
318 sub-process (such as a stand-alone simulator) and then communicates
319 with that. The sub-program to run is specified using the syntax
320 ``|<program> <args>'' vis:
322 (gdb) set remotedebug 1
323 (gdb) target extended-remote |mn10300-elf-sim program-args
325 * MIPS 64 remote protocol
327 A long standing bug in the mips64 remote protocol where by GDB
328 expected certain 32 bit registers (ex SR) to be transfered as 32
329 instead of 64 bits has been fixed.
331 The command ``set remote-mips64-transfers-32bit-regs on'' has been
332 added to provide backward compatibility with older versions of GDB.
334 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
336 The command ``set remotebinarydownload'' command has been replaced by
337 ``set remote X-packet''. Other commands in ``set remote'' family
338 include ``set remote P-packet''.
340 * Breakpoint commands accept ranges.
342 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
343 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
344 ``tracepoint passcount'' also accepts a range of tracepoints.
346 * ``apropos'' command added.
348 The ``apropos'' command searches through command names and
349 documentation strings, printing out matches, making it much easier to
350 try to find a command that does what you are looking for.
354 A new machine oriented interface (MI) has been added to GDB. This
355 interface is designed for debug environments running GDB as a separate
356 process. This is part of the long term libGDB project. See the
357 "GDB/MI" chapter of the GDB manual for further information. It can be
358 enabled by configuring with:
360 .../configure --enable-gdbmi
362 *** Changes in GDB-4.18:
364 * New native configurations
366 HP-UX 10.20 hppa*-*-hpux10.20
367 HP-UX 11.x hppa*-*-hpux11.0*
368 M68K Linux m68*-*-linux*
372 Fujitsu FR30 fr30-*-elf*
373 Intel StrongARM strongarm-*-*
374 Mitsubishi D30V d30v-*-*
376 * OBSOLETE configurations
378 Gould PowerNode, NP1 np1-*-*, pn-*-*
380 Configurations that have been declared obsolete will be commented out,
381 but the code will be left in place. If there is no activity to revive
382 these configurations before the next release of GDB, the sources will
383 be permanently REMOVED.
387 As a compatibility experiment, GDB's source files buildsym.h and
388 buildsym.c have been converted to pure standard C, no longer
389 containing any K&R compatibility code. We believe that all systems in
390 use today either come with a standard C compiler, or have a GCC port
391 available. If this is not true, please report the affected
392 configuration to bug-gdb@gnu.org immediately. See the README file for
393 information about getting a standard C compiler if you don't have one
398 GDB now uses readline 2.2.
400 * set extension-language
402 You can now control the mapping between filename extensions and source
403 languages by using the `set extension-language' command. For instance,
404 you can ask GDB to treat .c files as C++ by saying
405 set extension-language .c c++
406 The command `info extensions' lists all of the recognized extensions
407 and their associated languages.
409 * Setting processor type for PowerPC and RS/6000
411 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
412 you can use the `set processor' command to specify what variant of the
413 PowerPC family you are debugging. The command
417 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
418 following PowerPC and RS6000 variants:
420 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
421 rs6000 IBM RS6000 ("POWER") architecture, user-level view
423 403GC IBM PowerPC 403GC
424 505 Motorola PowerPC 505
425 860 Motorola PowerPC 860 or 850
426 601 Motorola PowerPC 601
427 602 Motorola PowerPC 602
428 603 Motorola/IBM PowerPC 603 or 603e
429 604 Motorola PowerPC 604 or 604e
430 750 Motorola/IBM PowerPC 750 or 750
432 At the moment, this command just tells GDB what to name the
433 special-purpose processor registers. Since almost all the affected
434 registers are inaccessible to user-level programs, this command is
435 only useful for remote debugging in its present form.
439 Thanks to a major code donation from Hewlett-Packard, GDB now has much
440 more extensive support for HP-UX. Added features include shared
441 library support, kernel threads and hardware watchpoints for 11.00,
442 support for HP's ANSI C and C++ compilers, and a compatibility mode
443 for xdb and dbx commands.
447 HP's donation includes the new concept of catchpoints, which is a
448 generalization of the old catch command. On HP-UX, it is now possible
449 to catch exec, fork, and vfork, as well as library loading.
451 This means that the existing catch command has changed; its first
452 argument now specifies the type of catch to be set up. See the
453 output of "help catch" for a list of catchpoint types.
455 * Debugging across forks
457 On HP-UX, you can choose which process to debug when a fork() happens
462 HP has donated a curses-based terminal user interface (TUI). To get
463 it, build with --enable-tui. Although this can be enabled for any
464 configuration, at present it only works for native HP debugging.
466 * GDB remote protocol additions
468 A new protocol packet 'X' that writes binary data is now available.
469 Default behavior is to try 'X', then drop back to 'M' if the stub
470 fails to respond. The settable variable `remotebinarydownload'
471 allows explicit control over the use of 'X'.
473 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
474 full 64-bit address. The command
476 set remoteaddresssize 32
478 can be used to revert to the old behaviour. For existing remote stubs
479 the change should not be noticed, as the additional address information
482 In order to assist in debugging stubs, you may use the maintenance
483 command `packet' to send any text string to the stub. For instance,
485 maint packet heythere
487 sends the packet "$heythere#<checksum>". Note that it is very easy to
488 disrupt a debugging session by sending the wrong packet at the wrong
491 The compare-sections command allows you to compare section data on the
492 target to what is in the executable file without uploading or
493 downloading, by comparing CRC checksums.
495 * Tracing can collect general expressions
497 You may now collect general expressions at tracepoints. This requires
498 further additions to the target-side stub; see tracepoint.c and
499 doc/agentexpr.texi for further details.
501 * mask-address variable for Mips
503 For Mips targets, you may control the zeroing of the upper 32 bits of
504 a 64-bit address by entering `set mask-address on'. This is mainly
505 of interest to users of embedded R4xxx and R5xxx processors.
507 * Higher serial baud rates
509 GDB's serial code now allows you to specify baud rates 57600, 115200,
510 230400, and 460800 baud. (Note that your host system may not be able
511 to achieve all of these rates.)
515 The i960 configuration now includes an initial implementation of a
516 builtin simulator, contributed by Jim Wilson.
519 *** Changes in GDB-4.17:
521 * New native configurations
523 Alpha GNU/Linux alpha*-*-linux*
524 Unixware 2.x i[3456]86-unixware2*
525 Irix 6.x mips*-sgi-irix6*
526 PowerPC GNU/Linux powerpc-*-linux*
527 PowerPC Solaris powerpcle-*-solaris*
528 Sparc GNU/Linux sparc-*-linux*
529 Motorola sysV68 R3V7.1 m68k-motorola-sysv
533 Argonaut Risc Chip (ARC) arc-*-*
534 Hitachi H8/300S h8300*-*-*
535 Matsushita MN10200 w/simulator mn10200-*-*
536 Matsushita MN10300 w/simulator mn10300-*-*
537 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
538 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
539 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
540 Mitsubishi D10V w/simulator d10v-*-*
541 Mitsubishi M32R/D w/simulator m32r-*-elf*
542 Tsqware Sparclet sparclet-*-*
543 NEC V850 w/simulator v850-*-*
545 * New debugging protocols
547 ARM with RDI protocol arm*-*-*
548 M68K with dBUG monitor m68*-*-{aout,coff,elf}
549 DDB and LSI variants of PMON protocol mips*-*-*
550 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
551 PowerPC with SDS protocol powerpc{,le}-*-eabi
552 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
556 All configurations can now understand and use the DWARF 2 debugging
557 format. The choice is automatic, if the symbol file contains DWARF 2
562 GDB now includes basic Java language support. This support is
563 only useful with Java compilers that produce native machine code.
565 * solib-absolute-prefix and solib-search-path
567 For SunOS and SVR4 shared libraries, you may now set the prefix for
568 loading absolute shared library symbol files, and the search path for
569 locating non-absolute shared library symbol files.
571 * Live range splitting
573 GDB can now effectively debug code for which GCC has performed live
574 range splitting as part of its optimization. See gdb/doc/LRS for
575 more details on the expected format of the stabs information.
579 GDB's support for the GNU Hurd, including thread debugging, has been
580 updated to work with current versions of the Hurd.
584 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
585 instruction set. ARM GDB automatically detects when Thumb
586 instructions are in use, and adjusts disassembly and backtracing
591 GDB's MIPS target configurations now handle the MIP16 16-bit
596 GDB now includes support for overlays; if an executable has been
597 linked such that multiple sections are based at the same address, GDB
598 will decide which section to use for symbolic info. You can choose to
599 control the decision manually, using overlay commands, or implement
600 additional target-side support and use "overlay load-target" to bring
601 in the overlay mapping. Do "help overlay" for more detail.
605 The command "info symbol <address>" displays information about
606 the symbol at the specified address.
610 The standard remote protocol now includes an extension that allows
611 asynchronous collection and display of trace data. This requires
612 extensive support in the target-side debugging stub. Tracing mode
613 includes a new interaction mode in GDB and new commands: see the
614 file tracepoint.c for more details.
618 Configurations for embedded MIPS now include a simulator contributed
619 by Cygnus Solutions. The simulator supports the instruction sets
620 of most MIPS variants.
624 Sparc configurations may now include the ERC32 simulator contributed
625 by the European Space Agency. The simulator is not built into
626 Sparc targets by default; configure with --enable-sim to include it.
630 For target configurations that may include multiple variants of a
631 basic architecture (such as MIPS and SH), you may now set the
632 architecture explicitly. "set arch" sets, "info arch" lists
633 the possible architectures.
635 *** Changes in GDB-4.16:
637 * New native configurations
639 Windows 95, x86 Windows NT i[345]86-*-cygwin32
640 M68K NetBSD m68k-*-netbsd*
641 PowerPC AIX 4.x powerpc-*-aix*
642 PowerPC MacOS powerpc-*-macos*
643 PowerPC Windows NT powerpcle-*-cygwin32
644 RS/6000 AIX 4.x rs6000-*-aix4*
648 ARM with RDP protocol arm-*-*
649 I960 with MON960 i960-*-coff
650 MIPS VxWorks mips*-*-vxworks*
651 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
652 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
654 Matra Sparclet sparclet-*-*
658 The powerpc-eabi configuration now includes the PSIM simulator,
659 contributed by Andrew Cagney, with assistance from Mike Meissner.
660 PSIM is a very elaborate model of the PowerPC, including not only
661 basic instruction set execution, but also details of execution unit
662 performance and I/O hardware. See sim/ppc/README for more details.
666 GDB now works with Solaris 2.5.
668 * Windows 95/NT native
670 GDB will now work as a native debugger on Windows 95 and Windows NT.
671 To build it from source, you must use the "gnu-win32" environment,
672 which uses a DLL to emulate enough of Unix to run the GNU tools.
673 Further information, binaries, and sources are available at
674 ftp.cygnus.com, under pub/gnu-win32.
676 * dont-repeat command
678 If a user-defined command includes the command `dont-repeat', then the
679 command will not be repeated if the user just types return. This is
680 useful if the command is time-consuming to run, so that accidental
681 extra keystrokes don't run the same command many times.
683 * Send break instead of ^C
685 The standard remote protocol now includes an option to send a break
686 rather than a ^C to the target in order to interrupt it. By default,
687 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
689 * Remote protocol timeout
691 The standard remote protocol includes a new variable `remotetimeout'
692 that allows you to set the number of seconds before GDB gives up trying
693 to read from the target. The default value is 2.
695 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
697 By default GDB will automatically keep track of objects as they are
698 loaded and unloaded by the dynamic linker. By using the command `set
699 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
700 when shared library events occur, thus allowing you to set breakpoints
701 in shared libraries which are explicitly loaded by the inferior.
703 Note this feature does not work on hpux8. On hpux9 you must link
704 /usr/lib/end.o into your program. This feature should work
705 automatically on hpux10.
707 * Irix 5.x hardware watchpoint support
709 Irix 5 configurations now support the use of hardware watchpoints.
711 * Mips protocol "SYN garbage limit"
713 When debugging a Mips target using the `target mips' protocol, you
714 may set the number of characters that GDB will ignore by setting
715 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
716 every character. The default value is 1050.
718 * Recording and replaying remote debug sessions
720 If you set `remotelogfile' to the name of a file, gdb will write to it
721 a recording of a remote debug session. This recording may then be
722 replayed back to gdb using "gdbreplay". See gdbserver/README for
723 details. This is useful when you have a problem with GDB while doing
724 remote debugging; you can make a recording of the session and send it
725 to someone else, who can then recreate the problem.
727 * Speedups for remote debugging
729 GDB includes speedups for downloading and stepping MIPS systems using
730 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
731 and more efficient S-record downloading.
733 * Memory use reductions and statistics collection
735 GDB now uses less memory and reports statistics about memory usage.
736 Try the `maint print statistics' command, for example.
738 *** Changes in GDB-4.15:
742 The symbol reader for AIX GDB now uses partial symbol tables. This
743 can greatly improve startup time, especially for large executables.
745 * Remote targets use caching
747 Remote targets now use a data cache to speed up communication with the
748 remote side. The data cache could lead to incorrect results because
749 it doesn't know about volatile variables, thus making it impossible to
750 debug targets which use memory mapped I/O devices. `set remotecache
751 off' turns the the data cache off.
753 * Remote targets may have threads
755 The standard remote protocol now includes support for multiple threads
756 in the target system, using new protocol commands 'H' and 'T'. See
757 gdb/remote.c for details.
761 If GDB is configured with `--enable-netrom', then it will include
762 support for the NetROM ROM emulator from XLNT Designs. The NetROM
763 acts as though it is a bank of ROM on the target board, but you can
764 write into it over the network. GDB's support consists only of
765 support for fast loading into the emulated ROM; to debug, you must use
766 another protocol, such as standard remote protocol. The usual
767 sequence is something like
769 target nrom <netrom-hostname>
771 target remote <netrom-hostname>:1235
775 GDB now includes support for the Apple Macintosh, as a host only. It
776 may be run as either an MPW tool or as a standalone application, and
777 it can debug through the serial port. All the usual GDB commands are
778 available, but to the target command, you must supply "serial" as the
779 device type instead of "/dev/ttyXX". See mpw-README in the main
780 directory for more information on how to build. The MPW configuration
781 scripts */mpw-config.in support only a few targets, and only the
782 mips-idt-ecoff target has been tested.
786 GDB configuration now uses autoconf. This is not user-visible,
787 but does simplify configuration and building.
791 GDB now supports hpux10.
793 *** Changes in GDB-4.14:
795 * New native configurations
797 x86 FreeBSD i[345]86-*-freebsd
798 x86 NetBSD i[345]86-*-netbsd
799 NS32k NetBSD ns32k-*-netbsd
800 Sparc NetBSD sparc-*-netbsd
804 A29K VxWorks a29k-*-vxworks
805 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
806 CPU32 EST-300 emulator m68*-*-est*
807 PowerPC ELF powerpc-*-elf
810 * Alpha OSF/1 support for procfs
812 GDB now supports procfs under OSF/1-2.x and higher, which makes it
813 possible to attach to running processes. As the mounting of the /proc
814 filesystem is optional on the Alpha, GDB automatically determines
815 the availability of /proc during startup. This can lead to problems
816 if /proc is unmounted after GDB has been started.
818 * Arguments to user-defined commands
820 User commands may accept up to 10 arguments separated by whitespace.
821 Arguments are accessed within the user command via $arg0..$arg9. A
824 print $arg0 + $arg1 + $arg2
826 To execute the command use:
829 Defines the command "adder" which prints the sum of its three arguments.
830 Note the arguments are text substitutions, so they may reference variables,
831 use complex expressions, or even perform inferior function calls.
833 * New `if' and `while' commands
835 This makes it possible to write more sophisticated user-defined
836 commands. Both commands take a single argument, which is the
837 expression to evaluate, and must be followed by the commands to
838 execute, one per line, if the expression is nonzero, the list being
839 terminated by the word `end'. The `if' command list may include an
840 `else' word, which causes the following commands to be executed only
841 if the expression is zero.
843 * Fortran source language mode
845 GDB now includes partial support for Fortran 77. It will recognize
846 Fortran programs and can evaluate a subset of Fortran expressions, but
847 variables and functions may not be handled correctly. GDB will work
848 with G77, but does not yet know much about symbols emitted by other
851 * Better HPUX support
853 Most debugging facilities now work on dynamic executables for HPPAs
854 running hpux9 or later. You can attach to running dynamically linked
855 processes, but by default the dynamic libraries will be read-only, so
856 for instance you won't be able to put breakpoints in them. To change
857 that behavior do the following before running the program:
863 This will cause the libraries to be mapped private and read-write.
864 To revert to the normal behavior, do this:
870 You cannot set breakpoints or examine data in the library until after
871 the library is loaded if the function/data symbols do not have
874 GDB can now also read debug symbols produced by the HP C compiler on
875 HPPAs (sorry, no C++, Fortran or 68k support).
877 * Target byte order now dynamically selectable
879 You can choose which byte order to use with a target system, via the
880 commands "set endian big" and "set endian little", and you can see the
881 current setting by using "show endian". You can also give the command
882 "set endian auto", in which case GDB will use the byte order
883 associated with the executable. Currently, only embedded MIPS
884 configurations support dynamic selection of target byte order.
886 * New DOS host serial code
888 This version uses DPMI interrupts to handle buffered I/O, so you
889 no longer need to run asynctsr when debugging boards connected to
892 *** Changes in GDB-4.13:
894 * New "complete" command
896 This lists all the possible completions for the rest of the line, if it
897 were to be given as a command itself. This is intended for use by emacs.
899 * Trailing space optional in prompt
901 "set prompt" no longer adds a space for you after the prompt you set. This
902 allows you to set a prompt which ends in a space or one that does not.
904 * Breakpoint hit counts
906 "info break" now displays a count of the number of times the breakpoint
907 has been hit. This is especially useful in conjunction with "ignore"; you
908 can ignore a large number of breakpoint hits, look at the breakpoint info
909 to see how many times the breakpoint was hit, then run again, ignoring one
910 less than that number, and this will get you quickly to the last hit of
913 * Ability to stop printing at NULL character
915 "set print null-stop" will cause GDB to stop printing the characters of
916 an array when the first NULL is encountered. This is useful when large
917 arrays actually contain only short strings.
919 * Shared library breakpoints
921 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
922 breakpoints in shared libraries before the executable is run.
924 * Hardware watchpoints
926 There is a new hardware breakpoint for the watch command for sparclite
927 targets. See gdb/sparclite/hw_breakpoint.note.
929 Hardware watchpoints are also now supported under Linux.
933 Annotations have been added. These are for use with graphical interfaces,
934 and are still experimental. Currently only gdba.el uses these.
936 * Improved Irix 5 support
938 GDB now works properly with Irix 5.2.
940 * Improved HPPA support
942 GDB now works properly with the latest GCC and GAS.
944 * New native configurations
946 Sequent PTX4 i[34]86-sequent-ptx4
947 HPPA running OSF/1 hppa*-*-osf*
948 Atari TT running SVR4 m68*-*-sysv4*
949 RS/6000 LynxOS rs6000-*-lynxos*
953 OS/9000 i[34]86-*-os9k
954 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
957 * Hitachi SH7000 and E7000-PC ICE support
959 There is now support for communicating with the Hitachi E7000-PC ICE.
960 This is available automatically when GDB is configured for the SH.
964 As usual, a variety of small fixes and improvements, both generic
965 and configuration-specific. See the ChangeLog for more detail.
967 *** Changes in GDB-4.12:
969 * Irix 5 is now supported
973 GDB-4.12 on the HPPA has a number of changes which make it unable
974 to debug the output from the currently released versions of GCC and
975 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
976 of GCC and GAS, versions of these tools designed to work with GDB-4.12
977 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
980 *** Changes in GDB-4.11:
982 * User visible changes:
986 The "set remotedebug" option is now consistent between the mips remote
987 target, remote targets using the gdb-specific protocol, UDI (AMD's
988 debug protocol for the 29k) and the 88k bug monitor. It is now an
989 integer specifying a debug level (normally 0 or 1, but 2 means more
990 debugging info for the mips target).
992 * DEC Alpha native support
994 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
995 debug info, but GDB works fairly well with the DEC compiler and should
996 work with a future GCC release. See the README file for a few
997 Alpha-specific notes.
999 * Preliminary thread implementation
1001 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
1003 * LynxOS native and target support for 386
1005 This release has been hosted on LynxOS 2.2, and also can be configured
1006 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
1009 * Improvements in C++ mangling/demangling.
1011 This release has much better g++ debugging, specifically in name
1012 mangling/demangling, virtual function calls, print virtual table,
1013 call methods, ...etc.
1015 *** Changes in GDB-4.10:
1017 * User visible changes:
1019 Remote debugging using the GDB-specific (`target remote') protocol now
1020 supports the `load' command. This is only useful if you have some
1021 other way of getting the stub to the target system, and you can put it
1022 somewhere in memory where it won't get clobbered by the download.
1024 Filename completion now works.
1026 When run under emacs mode, the "info line" command now causes the
1027 arrow to point to the line specified. Also, "info line" prints
1028 addresses in symbolic form (as well as hex).
1030 All vxworks based targets now support a user settable option, called
1031 vxworks-timeout. This option represents the number of seconds gdb
1032 should wait for responses to rpc's. You might want to use this if
1033 your vxworks target is, perhaps, a slow software simulator or happens
1034 to be on the far side of a thin network line.
1038 This release contains support for using a DEC alpha as a GDB host for
1039 cross debugging. Native alpha debugging is not supported yet.
1042 *** Changes in GDB-4.9:
1046 This is the first GDB release which is accompanied by a matching testsuite.
1047 The testsuite requires installation of dejagnu, which should be available
1048 via ftp from most sites that carry GNU software.
1052 'Cfront' style demangling has had its name changed to 'ARM' style, to
1053 emphasize that it was written from the specifications in the C++ Annotated
1054 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
1055 disclaimers, it still generated too much confusion with users attempting to
1056 use gdb with AT&T cfront.
1060 GDB now uses a standard remote interface to a simulator library.
1061 So far, the library contains simulators for the Zilog Z8001/2, the
1062 Hitachi H8/300, H8/500 and Super-H.
1064 * New targets supported
1066 H8/300 simulator h8300-hitachi-hms or h8300hms
1067 H8/500 simulator h8500-hitachi-hms or h8500hms
1068 SH simulator sh-hitachi-hms or sh
1069 Z8000 simulator z8k-zilog-none or z8ksim
1070 IDT MIPS board over serial line mips-idt-ecoff
1072 Cross-debugging to GO32 targets is supported. It requires a custom
1073 version of the i386-stub.c module which is integrated with the
1074 GO32 memory extender.
1076 * New remote protocols
1078 MIPS remote debugging protocol.
1080 * New source languages supported
1082 This version includes preliminary support for Chill, a Pascal like language
1083 used by telecommunications companies. Chill support is also being integrated
1084 into the GNU compiler, but we don't know when it will be publically available.
1087 *** Changes in GDB-4.8:
1089 * HP Precision Architecture supported
1091 GDB now supports HP PA-RISC machines running HPUX. A preliminary
1092 version of this support was available as a set of patches from the
1093 University of Utah. GDB does not support debugging of programs
1094 compiled with the HP compiler, because HP will not document their file
1095 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
1096 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
1098 Many problems in the preliminary version have been fixed.
1100 * Faster and better demangling
1102 We have improved template demangling and fixed numerous bugs in the GNU style
1103 demangler. It can now handle type modifiers such as `static' or `const'. Wide
1104 character types (wchar_t) are now supported. Demangling of each symbol is now
1105 only done once, and is cached when the symbol table for a file is read in.
1106 This results in a small increase in memory usage for C programs, a moderate
1107 increase in memory usage for C++ programs, and a fantastic speedup in
1110 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
1111 from the specifications in the Annotated Reference Manual, which AT&T's
1112 compiler does not actually implement.
1114 * G++ multiple inheritance compiler problem
1116 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
1117 inheritance lattices was reworked to properly discover ambiguities. We
1118 recently found an example which causes this new algorithm to fail in a
1119 very subtle way, producing bad debug information for those classes.
1120 The file 'gcc.patch' (in this directory) can be applied to gcc to
1121 circumvent the problem. A future GCC release will contain a complete
1124 The previous G++ debug info problem (mentioned below for the gdb-4.7
1125 release) is fixed in gcc version 2.3.2.
1127 * Improved configure script
1129 The `configure' script will now attempt to guess your system type if
1130 you don't supply a host system type. The old scheme of supplying a
1131 host system triplet is preferable over using this. All the magic is
1132 done in the new `config.guess' script. Examine it for details.
1134 We have also brought our configure script much more in line with the FSF's
1135 version. It now supports the --with-xxx options. In particular,
1136 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
1137 The resulting GDB will not be able to read arbitrary object file formats --
1138 only the format ``expected'' to be used on the configured target system.
1139 We hope to make this the default in a future release.
1141 * Documentation improvements
1143 There's new internal documentation on how to modify GDB, and how to
1144 produce clean changes to the code. We implore people to read it
1145 before submitting changes.
1147 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
1148 M4 macros. The new texinfo.tex is provided in this release. Pre-built
1149 `info' files are also provided. To build `info' files from scratch,
1150 you will need the latest `makeinfo' release, which will be available in
1151 a future texinfo-X.Y release.
1153 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
1154 We're not sure exactly which versions have this problem, but it has
1155 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
1156 or better. If that isn't possible, there is a patch in
1157 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
1158 around this problem.
1162 GDB now supports array constants that can be used in expressions typed in by
1163 the user. The syntax is `{element, element, ...}'. Ie: you can now type
1164 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
1167 The new directory `gdb/sparclite' contains a program that demonstrates
1168 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
1170 * New native hosts supported
1172 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
1173 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
1175 * New targets supported
1177 AMD 29k family via UDI a29k-amd-udi or udi29k
1179 * New file formats supported
1181 BFD now supports reading HP/PA-RISC executables (SOM file format?),
1182 HPUX core files, and SCO 3.2v2 core files.
1186 Attaching to processes now works again; thanks for the many bug reports.
1188 We have also stomped on a bunch of core dumps caused by
1189 printf_filtered("%s") problems.
1191 We eliminated a copyright problem on the rpc and ptrace header files
1192 for VxWorks, which was discovered at the last minute during the 4.7
1193 release. You should now be able to build a VxWorks GDB.
1195 You can now interrupt gdb while an attached process is running. This
1196 will cause the attached process to stop, and give control back to GDB.
1198 We fixed problems caused by using too many file descriptors
1199 for reading symbols from object files and libraries. This was
1200 especially a problem for programs that used many (~100) shared
1203 The `step' command now only enters a subroutine if there is line number
1204 information for the subroutine. Otherwise it acts like the `next'
1205 command. Previously, `step' would enter subroutines if there was
1206 any debugging information about the routine. This avoids problems
1207 when using `cc -g1' on MIPS machines.
1209 * Internal improvements
1211 GDB's internal interfaces have been improved to make it easier to support
1212 debugging of multiple languages in the future.
1214 GDB now uses a common structure for symbol information internally.
1215 Minimal symbols (derived from linkage symbols in object files), partial
1216 symbols (from a quick scan of debug information), and full symbols
1217 contain a common subset of information, making it easier to write
1218 shared code that handles any of them.
1220 * New command line options
1222 We now accept --silent as an alias for --quiet.
1226 The memory-mapped-malloc library is now licensed under the GNU Library
1227 General Public License.
1229 *** Changes in GDB-4.7:
1231 * Host/native/target split
1233 GDB has had some major internal surgery to untangle the support for
1234 hosts and remote targets. Now, when you configure GDB for a remote
1235 target, it will no longer load in all of the support for debugging
1236 local programs on the host. When fully completed and tested, this will
1237 ensure that arbitrary host/target combinations are possible.
1239 The primary conceptual shift is to separate the non-portable code in
1240 GDB into three categories. Host specific code is required any time GDB
1241 is compiled on that host, regardless of the target. Target specific
1242 code relates to the peculiarities of the target, but can be compiled on
1243 any host. Native specific code is everything else: it can only be
1244 built when the host and target are the same system. Child process
1245 handling and core file support are two common `native' examples.
1247 GDB's use of /proc for controlling Unix child processes is now cleaner.
1248 It has been split out into a single module under the `target_ops' vector,
1249 plus two native-dependent functions for each system that uses /proc.
1251 * New hosts supported
1253 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
1254 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1255 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
1257 * New targets supported
1259 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1260 68030 and CPU32 m68030-*-*, m68332-*-*
1262 * New native hosts supported
1264 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1265 (386bsd is not well tested yet)
1266 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
1268 * New file formats supported
1270 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
1271 supports reading of `a.out.adobe' object files, which are an a.out
1272 format extended with minimal information about multiple sections.
1276 `show copying' is the same as the old `info copying'.
1277 `show warranty' is the same as `info warrantee'.
1278 These were renamed for consistency. The old commands continue to work.
1280 `info handle' is a new alias for `info signals'.
1282 You can now define pre-command hooks, which attach arbitrary command
1283 scripts to any command. The commands in the hook will be executed
1284 prior to the user's command. You can also create a hook which will be
1285 executed whenever the program stops. See gdb.texinfo.
1289 We now deal with Cfront style name mangling, and can even extract type
1290 info from mangled symbols. GDB can automatically figure out which
1291 symbol mangling style your C++ compiler uses.
1293 Calling of methods and virtual functions has been improved as well.
1297 The crash that occured when debugging Sun Ansi-C compiled binaries is
1298 fixed. This was due to mishandling of the extra N_SO stabs output
1301 We also finally got Ultrix 4.2 running in house, and fixed core file
1302 support, with help from a dozen people on the net.
1304 John M. Farrell discovered that the reason that single-stepping was so
1305 slow on all of the Mips based platforms (primarily SGI and DEC) was
1306 that we were trying to demangle and lookup a symbol used for internal
1307 purposes on every instruction that was being stepped through. Changing
1308 the name of that symbol so that it couldn't be mistaken for a C++
1309 mangled symbol sped things up a great deal.
1311 Rich Pixley sped up symbol lookups in general by getting much smarter
1312 about when C++ symbol mangling is necessary. This should make symbol
1313 completion (TAB on the command line) much faster. It's not as fast as
1314 we'd like, but it's significantly faster than gdb-4.6.
1318 A new user controllable variable 'call_scratch_address' can
1319 specify the location of a scratch area to be used when GDB
1320 calls a function in the target. This is necessary because the
1321 usual method of putting the scratch area on the stack does not work
1322 in systems that have separate instruction and data spaces.
1324 We integrated changes to support the 29k UDI (Universal Debugger
1325 Interface), but discovered at the last minute that we didn't have all
1326 of the appropriate copyright paperwork. We are working with AMD to
1327 resolve this, and hope to have it available soon.
1331 We have sped up the remote serial line protocol, especially for targets
1332 with lots of registers. It now supports a new `expedited status' ('T')
1333 message which can be used in place of the existing 'S' status message.
1334 This allows the remote stub to send only the registers that GDB
1335 needs to make a quick decision about single-stepping or conditional
1336 breakpoints, eliminating the need to fetch the entire register set for
1337 each instruction being stepped through.
1339 The GDB remote serial protocol now implements a write-through cache for
1340 registers, only re-reading the registers if the target has run.
1342 There is also a new remote serial stub for SPARC processors. You can
1343 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
1344 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
1345 processor with a serial port.
1349 Configure.in files have become much easier to read and modify. A new
1350 `table driven' format makes it more obvious what configurations are
1351 supported, and what files each one uses.
1355 There is a new opcodes library which will eventually contain all of the
1356 disassembly routines and opcode tables. At present, it only contains
1357 Sparc and Z8000 routines. This will allow the assembler, debugger, and
1358 disassembler (binutils/objdump) to share these routines.
1360 The libiberty library is now copylefted under the GNU Library General
1361 Public License. This allows more liberal use, and was done so libg++
1362 can use it. This makes no difference to GDB, since the Library License
1363 grants all the rights from the General Public License.
1367 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
1368 reference to the stabs symbol info used by the debugger. It is (as far
1369 as we know) the only published document on this fascinating topic. We
1370 encourage you to read it, compare it to the stabs information on your
1371 system, and send improvements on the document in general (to
1372 bug-gdb@prep.ai.mit.edu).
1374 And, of course, many bugs have been fixed.
1377 *** Changes in GDB-4.6:
1379 * Better support for C++ function names
1381 GDB now accepts as input the "demangled form" of C++ overloaded function
1382 names and member function names, and can do command completion on such names
1383 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
1384 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
1385 Make use of command completion, it is your friend.
1387 GDB also now accepts a variety of C++ mangled symbol formats. They are
1388 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
1389 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
1390 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
1391 for the list of formats.
1393 * G++ symbol mangling problem
1395 Recent versions of gcc have a bug in how they emit debugging information for
1396 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
1397 directory) can be applied to gcc to fix the problem. Alternatively, if you
1398 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
1399 usual symptom is difficulty with setting breakpoints on methods. GDB complains
1400 about the method being non-existent. (We believe that version 2.2.2 of GCC has
1403 * New 'maintenance' command
1405 All of the commands related to hacking GDB internals have been moved out of
1406 the main command set, and now live behind the 'maintenance' command. This
1407 can also be abbreviated as 'mt'. The following changes were made:
1409 dump-me -> maintenance dump-me
1410 info all-breakpoints -> maintenance info breakpoints
1411 printmsyms -> maintenance print msyms
1412 printobjfiles -> maintenance print objfiles
1413 printpsyms -> maintenance print psymbols
1414 printsyms -> maintenance print symbols
1416 The following commands are new:
1418 maintenance demangle Call internal GDB demangler routine to
1419 demangle a C++ link name and prints the result.
1420 maintenance print type Print a type chain for a given symbol
1422 * Change to .gdbinit file processing
1424 We now read the $HOME/.gdbinit file before processing the argv arguments
1425 (e.g. reading symbol files or core files). This allows global parameters to
1426 be set, which will apply during the symbol reading. The ./.gdbinit is still
1427 read after argv processing.
1429 * New hosts supported
1431 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
1433 Linux support i386-unknown-linux or linux
1435 We are also including code to support the HP/PA running BSD and HPUX. This
1436 is almost guaranteed not to work, as we didn't have time to test or build it
1437 for this release. We are including it so that the more adventurous (or
1438 masochistic) of you can play with it. We also had major problems with the
1439 fact that the compiler that we got from HP doesn't support the -g option.
1442 * New targets supported
1444 Hitachi H8/300 h8300-hitachi-hms or h8300hms
1446 * More smarts about finding #include files
1448 GDB now remembers the compilation directory for all include files, and for
1449 all files from which C is generated (like yacc and lex sources). This
1450 greatly improves GDB's ability to find yacc/lex sources, and include files,
1451 especially if you are debugging your program from a directory different from
1452 the one that contains your sources.
1454 We also fixed a bug which caused difficulty with listing and setting
1455 breakpoints in include files which contain C code. (In the past, you had to
1456 try twice in order to list an include file that you hadn't looked at before.)
1458 * Interesting infernals change
1460 GDB now deals with arbitrary numbers of sections, where the symbols for each
1461 section must be relocated relative to that section's landing place in the
1462 target's address space. This work was needed to support ELF with embedded
1463 stabs used by Solaris-2.0.
1465 * Bug fixes (of course!)
1467 There have been loads of fixes for the following things:
1468 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
1469 i960, stabs, DOS(GO32), procfs, etc...
1471 See the ChangeLog for details.
1473 *** Changes in GDB-4.5:
1475 * New machines supported (host and target)
1477 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
1479 SGI Irix-4.x mips-sgi-irix4 or iris4
1481 * New malloc package
1483 GDB now uses a new memory manager called mmalloc, based on gmalloc.
1484 Mmalloc is capable of handling mutiple heaps of memory. It is also
1485 capable of saving a heap to a file, and then mapping it back in later.
1486 This can be used to greatly speedup the startup of GDB by using a
1487 pre-parsed symbol table which lives in a mmalloc managed heap. For
1488 more details, please read mmalloc/mmalloc.texi.
1492 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
1493 'help info proc' for details.
1495 * MIPS ecoff symbol table format
1497 The code that reads MIPS symbol table format is now supported on all hosts.
1498 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
1501 * File name changes for MS-DOS
1503 Many files in the config directories have been renamed to make it easier to
1504 support GDB on MS-DOSe systems (which have very restrictive file name
1505 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
1506 environment) is close to working but has some remaining problems. Note
1507 that debugging of DOS programs is not supported, due to limitations
1508 in the ``operating system'', but it can be used to host cross-debugging.
1510 * Cross byte order fixes
1512 Many fixes have been made to support cross debugging of Sparc and MIPS
1513 targets from hosts whose byte order differs.
1515 * New -mapped and -readnow options
1517 If memory-mapped files are available on your system through the 'mmap'
1518 system call, you can use the -mapped option on the `file' or
1519 `symbol-file' commands to cause GDB to write the symbols from your
1520 program into a reusable file. If the program you are debugging is
1521 called `/path/fred', the mapped symbol file will be `./fred.syms'.
1522 Future GDB debugging sessions will notice the presence of this file,
1523 and will quickly map in symbol information from it, rather than reading
1524 the symbol table from the executable program. Using the '-mapped'
1525 option in a GDB `file' or `symbol-file' command has the same effect as
1526 starting GDB with the '-mapped' command-line option.
1528 You can cause GDB to read the entire symbol table immediately by using
1529 the '-readnow' option with any of the commands that load symbol table
1530 information (or on the GDB command line). This makes the command
1531 slower, but makes future operations faster.
1533 The -mapped and -readnow options are typically combined in order to
1534 build a `fred.syms' file that contains complete symbol information.
1535 A simple GDB invocation to do nothing but build a `.syms' file for future
1538 gdb -batch -nx -mapped -readnow programname
1540 The `.syms' file is specific to the host machine on which GDB is run.
1541 It holds an exact image of GDB's internal symbol table. It cannot be
1542 shared across multiple host platforms.
1544 * longjmp() handling
1546 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
1547 siglongjmp() without losing control. This feature has not yet been ported to
1548 all systems. It currently works on many 386 platforms, all MIPS-based
1549 platforms (SGI, DECstation, etc), and Sun3/4.
1553 Preliminary work has been put in to support the new Solaris OS from Sun. At
1554 this time, it can control and debug processes, but it is not capable of
1559 As always, many many bug fixes. The major areas were with g++, and mipsread.
1560 People using the MIPS-based platforms should experience fewer mysterious
1561 crashes and trashed symbol tables.
1563 *** Changes in GDB-4.4:
1565 * New machines supported (host and target)
1567 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1569 BSD Reno on Vax vax-dec-bsd
1570 Ultrix on Vax vax-dec-ultrix
1572 * New machines supported (target)
1574 AMD 29000 embedded, using EBMON a29k-none-none
1578 GDB continues to improve its handling of C++. `References' work better.
1579 The demangler has also been improved, and now deals with symbols mangled as
1580 per the Annotated C++ Reference Guide.
1582 GDB also now handles `stabs' symbol information embedded in MIPS
1583 `ecoff' symbol tables. Since the ecoff format was not easily
1584 extensible to handle new languages such as C++, this appeared to be a
1585 good way to put C++ debugging info into MIPS binaries. This option
1586 will be supported in the GNU C compiler, version 2, when it is
1589 * New features for SVR4
1591 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
1592 shared libraries. Debugging dynamically linked programs should present
1593 only minor differences from debugging statically linked programs.
1595 The `info proc' command will print out information about any process
1596 on an SVR4 system (including the one you are debugging). At the moment,
1597 it prints the address mappings of the process.
1599 If you bring up GDB on another SVR4 system, please send mail to
1600 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
1602 * Better dynamic linking support in SunOS
1604 Reading symbols from shared libraries which contain debugging symbols
1605 now works properly. However, there remain issues such as automatic
1606 skipping of `transfer vector' code during function calls, which
1607 make it harder to debug code in a shared library, than to debug the
1608 same code linked statically.
1612 GDB is now using the latest `getopt' routines from the FSF. This
1613 version accepts the -- prefix for options with long names. GDB will
1614 continue to accept the old forms (-option and +option) as well.
1615 Various single letter abbreviations for options have been explicity
1616 added to the option table so that they won't get overshadowed in the
1617 future by other options that begin with the same letter.
1621 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
1622 Many assorted bugs have been handled. Many more remain to be handled.
1623 See the various ChangeLog files (primarily in gdb and bfd) for details.
1626 *** Changes in GDB-4.3:
1628 * New machines supported (host and target)
1630 Amiga 3000 running Amix m68k-cbm-svr4 or amix
1631 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
1632 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1634 * Almost SCO Unix support
1636 We had hoped to support:
1637 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1638 (except for core file support), but we discovered very late in the release
1639 that it has problems with process groups that render gdb unusable. Sorry
1640 about that. I encourage people to fix it and post the fixes.
1642 * Preliminary ELF and DWARF support
1644 GDB can read ELF object files on System V Release 4, and can handle
1645 debugging records for C, in DWARF format, in ELF files. This support
1646 is preliminary. If you bring up GDB on another SVR4 system, please
1647 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
1652 GDB now uses the latest `readline' library. One user-visible change
1653 is that two tabs will list possible command completions, which previously
1654 required typing M-? (meta-question mark, or ESC ?).
1658 The `stepi' bug that many of you noticed has been squashed.
1659 Many bugs in C++ have been handled. Many more remain to be handled.
1660 See the various ChangeLog files (primarily in gdb and bfd) for details.
1662 * State of the MIPS world (in case you wondered):
1664 GDB can understand the symbol tables emitted by the compilers
1665 supplied by most vendors of MIPS-based machines, including DEC. These
1666 symbol tables are in a format that essentially nobody else uses.
1668 Some versions of gcc come with an assembler post-processor called
1669 mips-tfile. This program is required if you want to do source-level
1670 debugging of gcc-compiled programs. I believe FSF does not ship
1671 mips-tfile with gcc version 1, but it will eventually come with gcc
1674 Debugging of g++ output remains a problem. g++ version 1.xx does not
1675 really support it at all. (If you're lucky, you should be able to get
1676 line numbers and stack traces to work, but no parameters or local
1677 variables.) With some work it should be possible to improve the
1680 When gcc version 2 is released, you will have somewhat better luck.
1681 However, even then you will get confusing results for inheritance and
1684 We will eventually provide full debugging of g++ output on
1685 DECstations. This will probably involve some kind of stabs-in-ecoff
1686 encapulation, but the details have not been worked out yet.
1689 *** Changes in GDB-4.2:
1691 * Improved configuration
1693 Only one copy of `configure' exists now, and it is not self-modifying.
1694 Porting BFD is simpler.
1698 The `step' and `next' commands now only stop at the first instruction
1699 of a source line. This prevents the multiple stops that used to occur
1700 in switch statements, for-loops, etc. `Step' continues to stop if a
1701 function that has debugging information is called within the line.
1705 Lots of small bugs fixed. More remain.
1707 * New host supported (not target)
1709 Intel 386 PC clone running Mach i386-none-mach
1712 *** Changes in GDB-4.1:
1714 * Multiple source language support
1716 GDB now has internal scaffolding to handle several source languages.
1717 It determines the type of each source file from its filename extension,
1718 and will switch expression parsing and number formatting to match the
1719 language of the function in the currently selected stack frame.
1720 You can also specifically set the language to be used, with
1721 `set language c' or `set language modula-2'.
1725 GDB now has preliminary support for the GNU Modula-2 compiler,
1726 currently under development at the State University of New York at
1727 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
1728 continue through the fall of 1991 and into 1992.
1730 Other Modula-2 compilers are currently not supported, and attempting to
1731 debug programs compiled with them will likely result in an error as the
1732 symbol table is read. Feel free to work on it, though!
1734 There are hooks in GDB for strict type checking and range checking,
1735 in the `Modula-2 philosophy', but they do not currently work.
1739 GDB can now write to executable and core files (e.g. patch
1740 a variable's value). You must turn this switch on, specify
1741 the file ("exec foo" or "core foo"), *then* modify it, e.g.
1742 by assigning a new value to a variable. Modifications take
1745 * Automatic SunOS shared library reading
1747 When you run your program, GDB automatically determines where its
1748 shared libraries (if any) have been loaded, and reads their symbols.
1749 The `share' command is no longer needed. This also works when
1750 examining core files.
1754 You can specify the number of lines that the `list' command shows.
1757 * New machines supported (host and target)
1759 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1760 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
1761 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
1763 * New hosts supported (not targets)
1765 IBM RT/PC: romp-ibm-aix or rtpc
1767 * New targets supported (not hosts)
1769 AMD 29000 embedded with COFF a29k-none-coff
1770 AMD 29000 embedded with a.out a29k-none-aout
1771 Ultracomputer remote kernel debug a29k-nyu-kern
1773 * New remote interfaces
1779 *** Changes in GDB-4.0:
1783 Wide output is wrapped at good places to make the output more readable.
1785 Gdb now supports cross-debugging from a host machine of one type to a
1786 target machine of another type. Communication with the target system
1787 is over serial lines. The ``target'' command handles connecting to the
1788 remote system; the ``load'' command will download a program into the
1789 remote system. Serial stubs for the m68k and i386 are provided. Gdb
1790 also supports debugging of realtime processes running under VxWorks,
1791 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
1792 stub on the target system.
1794 New CPUs supported include the AMD 29000 and Intel 960.
1796 GDB now reads object files and symbol tables via a ``binary file''
1797 library, which allows a single copy of GDB to debug programs of multiple
1798 object file types such as a.out and coff.
1800 There is now a GDB reference card in "doc/refcard.tex". (Make targets
1801 refcard.dvi and refcard.ps are available to format it).
1804 * Control-Variable user interface simplified
1806 All variables that control the operation of the debugger can be set
1807 by the ``set'' command, and displayed by the ``show'' command.
1809 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
1810 ``Show prompt'' produces the response:
1811 Gdb's prompt is new-gdb=>.
1813 What follows are the NEW set commands. The command ``help set'' will
1814 print a complete list of old and new set commands. ``help set FOO''
1815 will give a longer description of the variable FOO. ``show'' will show
1816 all of the variable descriptions and their current settings.
1818 confirm on/off: Enables warning questions for operations that are
1819 hard to recover from, e.g. rerunning the program while
1820 it is already running. Default is ON.
1822 editing on/off: Enables EMACS style command line editing
1823 of input. Previous lines can be recalled with
1824 control-P, the current line can be edited with control-B,
1825 you can search for commands with control-R, etc.
1828 history filename NAME: NAME is where the gdb command history
1829 will be stored. The default is .gdb_history,
1830 or the value of the environment variable
1833 history size N: The size, in commands, of the command history. The
1834 default is 256, or the value of the environment variable
1837 history save on/off: If this value is set to ON, the history file will
1838 be saved after exiting gdb. If set to OFF, the
1839 file will not be saved. The default is OFF.
1841 history expansion on/off: If this value is set to ON, then csh-like
1842 history expansion will be performed on
1843 command line input. The default is OFF.
1845 radix N: Sets the default radix for input and output. It can be set
1846 to 8, 10, or 16. Note that the argument to "radix" is interpreted
1847 in the current radix, so "set radix 10" is always a no-op.
1849 height N: This integer value is the number of lines on a page. Default
1850 is 24, the current `stty rows'' setting, or the ``li#''
1851 setting from the termcap entry matching the environment
1854 width N: This integer value is the number of characters on a line.
1855 Default is 80, the current `stty cols'' setting, or the ``co#''
1856 setting from the termcap entry matching the environment
1859 Note: ``set screensize'' is obsolete. Use ``set height'' and
1860 ``set width'' instead.
1862 print address on/off: Print memory addresses in various command displays,
1863 such as stack traces and structure values. Gdb looks
1864 more ``symbolic'' if you turn this off; it looks more
1865 ``machine level'' with it on. Default is ON.
1867 print array on/off: Prettyprint arrays. New convenient format! Default
1870 print demangle on/off: Print C++ symbols in "source" form if on,
1873 print asm-demangle on/off: Same, for assembler level printouts
1876 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
1879 * Support for Epoch Environment.
1881 The epoch environment is a version of Emacs v18 with windowing. One
1882 new command, ``inspect'', is identical to ``print'', except that if you
1883 are running in the epoch environment, the value is printed in its own
1887 * Support for Shared Libraries
1889 GDB can now debug programs and core files that use SunOS shared libraries.
1890 Symbols from a shared library cannot be referenced
1891 before the shared library has been linked with the program (this
1892 happens after you type ``run'' and before the function main() is entered).
1893 At any time after this linking (including when examining core files
1894 from dynamically linked programs), gdb reads the symbols from each
1895 shared library when you type the ``sharedlibrary'' command.
1896 It can be abbreviated ``share''.
1898 sharedlibrary REGEXP: Load shared object library symbols for files
1899 matching a unix regular expression. No argument
1900 indicates to load symbols for all shared libraries.
1902 info sharedlibrary: Status of loaded shared libraries.
1907 A watchpoint stops execution of a program whenever the value of an
1908 expression changes. Checking for this slows down execution
1909 tremendously whenever you are in the scope of the expression, but is
1910 quite useful for catching tough ``bit-spreader'' or pointer misuse
1911 problems. Some machines such as the 386 have hardware for doing this
1912 more quickly, and future versions of gdb will use this hardware.
1914 watch EXP: Set a watchpoint (breakpoint) for an expression.
1916 info watchpoints: Information about your watchpoints.
1918 delete N: Deletes watchpoint number N (same as breakpoints).
1919 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
1920 enable N: Re-enables watchpoint number N (same as breakpoints).
1923 * C++ multiple inheritance
1925 When used with a GCC version 2 compiler, GDB supports multiple inheritance
1928 * C++ exception handling
1930 Gdb now supports limited C++ exception handling. Besides the existing
1931 ability to breakpoint on an exception handler, gdb can breakpoint on
1932 the raising of an exception (before the stack is peeled back to the
1935 catch FOO: If there is a FOO exception handler in the dynamic scope,
1936 set a breakpoint to catch exceptions which may be raised there.
1937 Multiple exceptions (``catch foo bar baz'') may be caught.
1939 info catch: Lists all exceptions which may be caught in the
1940 current stack frame.
1943 * Minor command changes
1945 The command ``call func (arg, arg, ...)'' now acts like the print
1946 command, except it does not print or save a value if the function's result
1947 is void. This is similar to dbx usage.
1949 The ``up'' and ``down'' commands now always print the frame they end up
1950 at; ``up-silently'' and `down-silently'' can be used in scripts to change
1951 frames without printing.
1953 * New directory command
1955 'dir' now adds directories to the FRONT of the source search path.
1956 The path starts off empty. Source files that contain debug information
1957 about the directory in which they were compiled can be found even
1958 with an empty path; Sun CC and GCC include this information. If GDB can't
1959 find your source file in the current directory, type "dir .".
1961 * Configuring GDB for compilation
1963 For normal use, type ``./configure host''. See README or gdb.texinfo
1966 GDB now handles cross debugging. If you are remotely debugging between
1967 two different machines, type ``./configure host -target=targ''.
1968 Host is the machine where GDB will run; targ is the machine
1969 where the program that you are debugging will run.