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*
12 Sanyo XStormy16 xstormy16-elf
14 * REMOVED configurations and files
16 TI TMS320C80 tic80-*-*
18 PowerPC Solaris powerpcle-*-solaris*
19 PowerPC Windows NT powerpcle-*-cygwin32
20 PowerPC Netware powerpc-*-netware*
21 Harris/CXUX m88k m88*-harris-cxux*
22 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
23 ns32k-utek-sysv* ns32k-utek-*
24 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
25 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
26 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
27 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
28 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
30 * Changes to command line processing
32 The new `--args' feature can be used to specify command-line arguments
33 for the inferior from gdb's command line.
35 * Changes to key bindings
37 There is a new `operate-and-get-next' function bound to `C-o'.
39 *** Changes in GDB 5.1:
41 * New native configurations
43 Alpha FreeBSD alpha*-*-freebsd*
44 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
45 MIPS Linux mips*-*-linux*
46 MIPS SGI Irix 6.x mips*-sgi-irix6*
48 s390 and s390x Linux {s390,s390x}-*-linux*
52 Motorola 68HC11 and 68HC12 m68hc11-elf
54 UltraSparc running Linux sparc64-*-linux*
56 * OBSOLETE configurations and files
58 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
59 Harris/CXUX m88k m88*-harris-cxux*
60 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
61 ns32k-utek-sysv* ns32k-utek-*
62 TI TMS320C80 tic80-*-*
64 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
65 PowerPC Solaris powerpcle-*-solaris*
66 PowerPC Windows NT powerpcle-*-cygwin32
67 PowerPC Netware powerpc-*-netware*
68 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
69 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
70 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
71 Apple Macintosh (MPW) host N/A
73 stuff.c (Program to stuff files into a specially prepared space in kdb)
74 kdb-start.c (Main loop for the standalone kernel debugger)
76 Configurations that have been declared obsolete in this release have
77 been commented out. Unless there is activity to revive these
78 configurations, the next release of GDB will have their sources
81 * REMOVED configurations and files
83 Altos 3068 m68*-altos-*
86 ARM RISCix arm-*-* (as host)
90 * GDB has been converted to ISO C.
92 GDB's source code has been converted to ISO C. In particular, the
93 sources are fully protoized, and rely on standard headers being
98 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
100 * The MI enabled by default.
102 The new machine oriented interface (MI) introduced in GDB 5.0 has been
103 revised and enabled by default. Packages which use GDB as a debugging
104 engine behind a UI or another front end are encouraged to switch to
105 using the GDB/MI interface, instead of the old annotations interface
106 which is now deprecated.
108 * Support for debugging Pascal programs.
110 GDB now includes support for debugging Pascal programs. The following
111 main features are supported:
113 - Pascal-specific data types such as sets;
115 - automatic recognition of Pascal sources based on file-name
118 - Pascal-style display of data types, variables, and functions;
120 - a Pascal expression parser.
122 However, some important features are not yet supported.
124 - Pascal string operations are not supported at all;
126 - there are some problems with boolean types;
128 - Pascal type hexadecimal constants are not supported
129 because they conflict with the internal variables format;
131 - support for Pascal objects and classes is not full yet;
133 - unlike Pascal, GDB is case-sensitive for symbol names.
135 * Changes in completion.
137 Commands such as `shell', `run' and `set args', which pass arguments
138 to inferior programs, now complete on file names, similar to what
139 users expect at the shell prompt.
141 Commands which accept locations, such as `disassemble', `print',
142 `breakpoint', `until', etc. now complete on filenames as well as
143 program symbols. Thus, if you type "break foob TAB", and the source
144 files linked into the programs include `foobar.c', that file name will
145 be one of the candidates for completion. However, file names are not
146 considered for completion after you typed a colon that delimits a file
147 name from a name of a function in that file, as in "break foo.c:bar".
149 `set demangle-style' completes on available demangling styles.
151 * New platform-independent commands:
153 It is now possible to define a post-hook for a command as well as a
154 hook that runs before the command. For more details, see the
155 documentation of `hookpost' in the GDB manual.
157 * Changes in GNU/Linux native debugging.
159 Support for debugging multi-threaded programs has been completely
160 revised for all platforms except m68k and sparc. You can now debug as
161 many threads as your system allows you to have.
163 Attach/detach is supported for multi-threaded programs.
165 Support for SSE registers was added for x86. This doesn't work for
166 multi-threaded programs though.
168 * Changes in MIPS configurations.
170 Multi-arch support is enabled for all MIPS configurations.
172 GDB can now be built as native debugger on SGI Irix 6.x systems for
173 debugging n32 executables. (Debugging 64-bit executables is not yet
176 * Unified support for hardware watchpoints in all x86 configurations.
178 Most (if not all) native x86 configurations support hardware-assisted
179 breakpoints and watchpoints in a unified manner. This support
180 implements debug register sharing between watchpoints, which allows to
181 put a virtually infinite number of watchpoints on the same address,
182 and also supports watching regions up to 16 bytes with several debug
185 The new maintenance command `maintenance show-debug-regs' toggles
186 debugging print-outs in functions that insert, remove, and test
187 watchpoints and hardware breakpoints.
189 * Changes in the DJGPP native configuration.
191 New command ``info dos sysinfo'' displays assorted information about
192 the CPU, OS, memory, and DPMI server.
194 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
195 display information about segment descriptors stored in GDT, LDT, and
198 New commands ``info dos pde'' and ``info dos pte'' display entries
199 from Page Directory and Page Tables (for now works with CWSDPMI only).
200 New command ``info dos address-pte'' displays the Page Table entry for
201 a given linear address.
203 GDB can now pass command lines longer than 126 characters to the
204 program being debugged (requires an update to the libdbg.a library
205 which is part of the DJGPP development kit).
207 DWARF2 debug info is now supported.
209 It is now possible to `step' and `next' through calls to `longjmp'.
211 * Changes in documentation.
213 All GDB documentation was converted to GFDL, the GNU Free
214 Documentation License.
216 Tracepoints-related commands are now fully documented in the GDB
219 TUI, the Text-mode User Interface, is now documented in the manual.
221 Tracepoints-related commands are now fully documented in the GDB
224 The "GDB Internals" manual now has an index. It also includes
225 documentation of `ui_out' functions, GDB coding standards, x86
226 hardware watchpoints, and memory region attributes.
228 * GDB's version number moved to ``version.in''
230 The Makefile variable VERSION has been replaced by the file
231 ``version.in''. People creating GDB distributions should update the
232 contents of this file.
236 GUD support is now a standard part of the EMACS distribution.
238 *** Changes in GDB 5.0:
240 * Improved support for debugging FP programs on x86 targets
242 Unified and much-improved support for debugging floating-point
243 programs on all x86 targets. In particular, ``info float'' now
244 displays the FP registers in the same format on all x86 targets, with
245 greater level of detail.
247 * Improvements and bugfixes in hardware-assisted watchpoints
249 It is now possible to watch array elements, struct members, and
250 bitfields with hardware-assisted watchpoints. Data-read watchpoints
251 on x86 targets no longer erroneously trigger when the address is
254 * Improvements in the native DJGPP version of GDB
256 The distribution now includes all the scripts and auxiliary files
257 necessary to build the native DJGPP version on MS-DOS/MS-Windows
258 machines ``out of the box''.
260 The DJGPP version can now debug programs that use signals. It is
261 possible to catch signals that happened in the debuggee, deliver
262 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
263 would kill the program being debugged.) Programs that hook hardware
264 interrupts (keyboard, timer, etc.) can also be debugged.
266 It is now possible to debug DJGPP programs that redirect their
267 standard handles or switch them to raw (as opposed to cooked) mode, or
268 even close them. The command ``run < foo > bar'' works as expected,
269 and ``info terminal'' reports useful information about the debuggee's
270 terminal, including raw/cooked mode, redirection, etc.
272 The DJGPP version now uses termios functions for console I/O, which
273 enables debugging graphics programs. Interrupting GDB with Ctrl-C
276 DOS-style file names with drive letters are now fully supported by
279 It is now possible to debug DJGPP programs that switch their working
280 directory. It is also possible to rerun the debuggee any number of
281 times without restarting GDB; thus, you can use the same setup,
282 breakpoints, etc. for many debugging sessions.
284 * New native configurations
286 ARM GNU/Linux arm*-*-linux*
287 PowerPC GNU/Linux powerpc-*-linux*
291 Motorola MCore mcore-*-*
292 x86 VxWorks i[3456]86-*-vxworks*
293 PowerPC VxWorks powerpc-*-vxworks*
294 TI TMS320C80 tic80-*-*
296 * OBSOLETE configurations
298 Altos 3068 m68*-altos-*
299 Convex c1-*-*, c2-*-*
301 ARM RISCix arm-*-* (as host)
304 Configurations that have been declared obsolete will be commented out,
305 but the code will be left in place. If there is no activity to revive
306 these configurations before the next release of GDB, the sources will
307 be permanently REMOVED.
309 * Gould support removed
311 Support for the Gould PowerNode and NP1 has been removed.
313 * New features for SVR4
315 On SVR4 native platforms (such as Solaris), if you attach to a process
316 without first loading a symbol file, GDB will now attempt to locate and
317 load symbols from the running process's executable file.
319 * Many C++ enhancements
321 C++ support has been greatly improved. Overload resolution now works properly
322 in almost all cases. RTTI support is on the way.
324 * Remote targets can connect to a sub-program
326 A popen(3) style serial-device has been added. This device starts a
327 sub-process (such as a stand-alone simulator) and then communicates
328 with that. The sub-program to run is specified using the syntax
329 ``|<program> <args>'' vis:
331 (gdb) set remotedebug 1
332 (gdb) target extended-remote |mn10300-elf-sim program-args
334 * MIPS 64 remote protocol
336 A long standing bug in the mips64 remote protocol where by GDB
337 expected certain 32 bit registers (ex SR) to be transfered as 32
338 instead of 64 bits has been fixed.
340 The command ``set remote-mips64-transfers-32bit-regs on'' has been
341 added to provide backward compatibility with older versions of GDB.
343 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
345 The command ``set remotebinarydownload'' command has been replaced by
346 ``set remote X-packet''. Other commands in ``set remote'' family
347 include ``set remote P-packet''.
349 * Breakpoint commands accept ranges.
351 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
352 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
353 ``tracepoint passcount'' also accepts a range of tracepoints.
355 * ``apropos'' command added.
357 The ``apropos'' command searches through command names and
358 documentation strings, printing out matches, making it much easier to
359 try to find a command that does what you are looking for.
363 A new machine oriented interface (MI) has been added to GDB. This
364 interface is designed for debug environments running GDB as a separate
365 process. This is part of the long term libGDB project. See the
366 "GDB/MI" chapter of the GDB manual for further information. It can be
367 enabled by configuring with:
369 .../configure --enable-gdbmi
371 *** Changes in GDB-4.18:
373 * New native configurations
375 HP-UX 10.20 hppa*-*-hpux10.20
376 HP-UX 11.x hppa*-*-hpux11.0*
377 M68K Linux m68*-*-linux*
381 Fujitsu FR30 fr30-*-elf*
382 Intel StrongARM strongarm-*-*
383 Mitsubishi D30V d30v-*-*
385 * OBSOLETE configurations
387 Gould PowerNode, NP1 np1-*-*, pn-*-*
389 Configurations that have been declared obsolete will be commented out,
390 but the code will be left in place. If there is no activity to revive
391 these configurations before the next release of GDB, the sources will
392 be permanently REMOVED.
396 As a compatibility experiment, GDB's source files buildsym.h and
397 buildsym.c have been converted to pure standard C, no longer
398 containing any K&R compatibility code. We believe that all systems in
399 use today either come with a standard C compiler, or have a GCC port
400 available. If this is not true, please report the affected
401 configuration to bug-gdb@gnu.org immediately. See the README file for
402 information about getting a standard C compiler if you don't have one
407 GDB now uses readline 2.2.
409 * set extension-language
411 You can now control the mapping between filename extensions and source
412 languages by using the `set extension-language' command. For instance,
413 you can ask GDB to treat .c files as C++ by saying
414 set extension-language .c c++
415 The command `info extensions' lists all of the recognized extensions
416 and their associated languages.
418 * Setting processor type for PowerPC and RS/6000
420 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
421 you can use the `set processor' command to specify what variant of the
422 PowerPC family you are debugging. The command
426 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
427 following PowerPC and RS6000 variants:
429 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
430 rs6000 IBM RS6000 ("POWER") architecture, user-level view
432 403GC IBM PowerPC 403GC
433 505 Motorola PowerPC 505
434 860 Motorola PowerPC 860 or 850
435 601 Motorola PowerPC 601
436 602 Motorola PowerPC 602
437 603 Motorola/IBM PowerPC 603 or 603e
438 604 Motorola PowerPC 604 or 604e
439 750 Motorola/IBM PowerPC 750 or 750
441 At the moment, this command just tells GDB what to name the
442 special-purpose processor registers. Since almost all the affected
443 registers are inaccessible to user-level programs, this command is
444 only useful for remote debugging in its present form.
448 Thanks to a major code donation from Hewlett-Packard, GDB now has much
449 more extensive support for HP-UX. Added features include shared
450 library support, kernel threads and hardware watchpoints for 11.00,
451 support for HP's ANSI C and C++ compilers, and a compatibility mode
452 for xdb and dbx commands.
456 HP's donation includes the new concept of catchpoints, which is a
457 generalization of the old catch command. On HP-UX, it is now possible
458 to catch exec, fork, and vfork, as well as library loading.
460 This means that the existing catch command has changed; its first
461 argument now specifies the type of catch to be set up. See the
462 output of "help catch" for a list of catchpoint types.
464 * Debugging across forks
466 On HP-UX, you can choose which process to debug when a fork() happens
471 HP has donated a curses-based terminal user interface (TUI). To get
472 it, build with --enable-tui. Although this can be enabled for any
473 configuration, at present it only works for native HP debugging.
475 * GDB remote protocol additions
477 A new protocol packet 'X' that writes binary data is now available.
478 Default behavior is to try 'X', then drop back to 'M' if the stub
479 fails to respond. The settable variable `remotebinarydownload'
480 allows explicit control over the use of 'X'.
482 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
483 full 64-bit address. The command
485 set remoteaddresssize 32
487 can be used to revert to the old behaviour. For existing remote stubs
488 the change should not be noticed, as the additional address information
491 In order to assist in debugging stubs, you may use the maintenance
492 command `packet' to send any text string to the stub. For instance,
494 maint packet heythere
496 sends the packet "$heythere#<checksum>". Note that it is very easy to
497 disrupt a debugging session by sending the wrong packet at the wrong
500 The compare-sections command allows you to compare section data on the
501 target to what is in the executable file without uploading or
502 downloading, by comparing CRC checksums.
504 * Tracing can collect general expressions
506 You may now collect general expressions at tracepoints. This requires
507 further additions to the target-side stub; see tracepoint.c and
508 doc/agentexpr.texi for further details.
510 * mask-address variable for Mips
512 For Mips targets, you may control the zeroing of the upper 32 bits of
513 a 64-bit address by entering `set mask-address on'. This is mainly
514 of interest to users of embedded R4xxx and R5xxx processors.
516 * Higher serial baud rates
518 GDB's serial code now allows you to specify baud rates 57600, 115200,
519 230400, and 460800 baud. (Note that your host system may not be able
520 to achieve all of these rates.)
524 The i960 configuration now includes an initial implementation of a
525 builtin simulator, contributed by Jim Wilson.
528 *** Changes in GDB-4.17:
530 * New native configurations
532 Alpha GNU/Linux alpha*-*-linux*
533 Unixware 2.x i[3456]86-unixware2*
534 Irix 6.x mips*-sgi-irix6*
535 PowerPC GNU/Linux powerpc-*-linux*
536 PowerPC Solaris powerpcle-*-solaris*
537 Sparc GNU/Linux sparc-*-linux*
538 Motorola sysV68 R3V7.1 m68k-motorola-sysv
542 Argonaut Risc Chip (ARC) arc-*-*
543 Hitachi H8/300S h8300*-*-*
544 Matsushita MN10200 w/simulator mn10200-*-*
545 Matsushita MN10300 w/simulator mn10300-*-*
546 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
547 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
548 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
549 Mitsubishi D10V w/simulator d10v-*-*
550 Mitsubishi M32R/D w/simulator m32r-*-elf*
551 Tsqware Sparclet sparclet-*-*
552 NEC V850 w/simulator v850-*-*
554 * New debugging protocols
556 ARM with RDI protocol arm*-*-*
557 M68K with dBUG monitor m68*-*-{aout,coff,elf}
558 DDB and LSI variants of PMON protocol mips*-*-*
559 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
560 PowerPC with SDS protocol powerpc{,le}-*-eabi
561 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
565 All configurations can now understand and use the DWARF 2 debugging
566 format. The choice is automatic, if the symbol file contains DWARF 2
571 GDB now includes basic Java language support. This support is
572 only useful with Java compilers that produce native machine code.
574 * solib-absolute-prefix and solib-search-path
576 For SunOS and SVR4 shared libraries, you may now set the prefix for
577 loading absolute shared library symbol files, and the search path for
578 locating non-absolute shared library symbol files.
580 * Live range splitting
582 GDB can now effectively debug code for which GCC has performed live
583 range splitting as part of its optimization. See gdb/doc/LRS for
584 more details on the expected format of the stabs information.
588 GDB's support for the GNU Hurd, including thread debugging, has been
589 updated to work with current versions of the Hurd.
593 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
594 instruction set. ARM GDB automatically detects when Thumb
595 instructions are in use, and adjusts disassembly and backtracing
600 GDB's MIPS target configurations now handle the MIP16 16-bit
605 GDB now includes support for overlays; if an executable has been
606 linked such that multiple sections are based at the same address, GDB
607 will decide which section to use for symbolic info. You can choose to
608 control the decision manually, using overlay commands, or implement
609 additional target-side support and use "overlay load-target" to bring
610 in the overlay mapping. Do "help overlay" for more detail.
614 The command "info symbol <address>" displays information about
615 the symbol at the specified address.
619 The standard remote protocol now includes an extension that allows
620 asynchronous collection and display of trace data. This requires
621 extensive support in the target-side debugging stub. Tracing mode
622 includes a new interaction mode in GDB and new commands: see the
623 file tracepoint.c for more details.
627 Configurations for embedded MIPS now include a simulator contributed
628 by Cygnus Solutions. The simulator supports the instruction sets
629 of most MIPS variants.
633 Sparc configurations may now include the ERC32 simulator contributed
634 by the European Space Agency. The simulator is not built into
635 Sparc targets by default; configure with --enable-sim to include it.
639 For target configurations that may include multiple variants of a
640 basic architecture (such as MIPS and SH), you may now set the
641 architecture explicitly. "set arch" sets, "info arch" lists
642 the possible architectures.
644 *** Changes in GDB-4.16:
646 * New native configurations
648 Windows 95, x86 Windows NT i[345]86-*-cygwin32
649 M68K NetBSD m68k-*-netbsd*
650 PowerPC AIX 4.x powerpc-*-aix*
651 PowerPC MacOS powerpc-*-macos*
652 PowerPC Windows NT powerpcle-*-cygwin32
653 RS/6000 AIX 4.x rs6000-*-aix4*
657 ARM with RDP protocol arm-*-*
658 I960 with MON960 i960-*-coff
659 MIPS VxWorks mips*-*-vxworks*
660 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
661 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
663 Matra Sparclet sparclet-*-*
667 The powerpc-eabi configuration now includes the PSIM simulator,
668 contributed by Andrew Cagney, with assistance from Mike Meissner.
669 PSIM is a very elaborate model of the PowerPC, including not only
670 basic instruction set execution, but also details of execution unit
671 performance and I/O hardware. See sim/ppc/README for more details.
675 GDB now works with Solaris 2.5.
677 * Windows 95/NT native
679 GDB will now work as a native debugger on Windows 95 and Windows NT.
680 To build it from source, you must use the "gnu-win32" environment,
681 which uses a DLL to emulate enough of Unix to run the GNU tools.
682 Further information, binaries, and sources are available at
683 ftp.cygnus.com, under pub/gnu-win32.
685 * dont-repeat command
687 If a user-defined command includes the command `dont-repeat', then the
688 command will not be repeated if the user just types return. This is
689 useful if the command is time-consuming to run, so that accidental
690 extra keystrokes don't run the same command many times.
692 * Send break instead of ^C
694 The standard remote protocol now includes an option to send a break
695 rather than a ^C to the target in order to interrupt it. By default,
696 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
698 * Remote protocol timeout
700 The standard remote protocol includes a new variable `remotetimeout'
701 that allows you to set the number of seconds before GDB gives up trying
702 to read from the target. The default value is 2.
704 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
706 By default GDB will automatically keep track of objects as they are
707 loaded and unloaded by the dynamic linker. By using the command `set
708 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
709 when shared library events occur, thus allowing you to set breakpoints
710 in shared libraries which are explicitly loaded by the inferior.
712 Note this feature does not work on hpux8. On hpux9 you must link
713 /usr/lib/end.o into your program. This feature should work
714 automatically on hpux10.
716 * Irix 5.x hardware watchpoint support
718 Irix 5 configurations now support the use of hardware watchpoints.
720 * Mips protocol "SYN garbage limit"
722 When debugging a Mips target using the `target mips' protocol, you
723 may set the number of characters that GDB will ignore by setting
724 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
725 every character. The default value is 1050.
727 * Recording and replaying remote debug sessions
729 If you set `remotelogfile' to the name of a file, gdb will write to it
730 a recording of a remote debug session. This recording may then be
731 replayed back to gdb using "gdbreplay". See gdbserver/README for
732 details. This is useful when you have a problem with GDB while doing
733 remote debugging; you can make a recording of the session and send it
734 to someone else, who can then recreate the problem.
736 * Speedups for remote debugging
738 GDB includes speedups for downloading and stepping MIPS systems using
739 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
740 and more efficient S-record downloading.
742 * Memory use reductions and statistics collection
744 GDB now uses less memory and reports statistics about memory usage.
745 Try the `maint print statistics' command, for example.
747 *** Changes in GDB-4.15:
751 The symbol reader for AIX GDB now uses partial symbol tables. This
752 can greatly improve startup time, especially for large executables.
754 * Remote targets use caching
756 Remote targets now use a data cache to speed up communication with the
757 remote side. The data cache could lead to incorrect results because
758 it doesn't know about volatile variables, thus making it impossible to
759 debug targets which use memory mapped I/O devices. `set remotecache
760 off' turns the the data cache off.
762 * Remote targets may have threads
764 The standard remote protocol now includes support for multiple threads
765 in the target system, using new protocol commands 'H' and 'T'. See
766 gdb/remote.c for details.
770 If GDB is configured with `--enable-netrom', then it will include
771 support for the NetROM ROM emulator from XLNT Designs. The NetROM
772 acts as though it is a bank of ROM on the target board, but you can
773 write into it over the network. GDB's support consists only of
774 support for fast loading into the emulated ROM; to debug, you must use
775 another protocol, such as standard remote protocol. The usual
776 sequence is something like
778 target nrom <netrom-hostname>
780 target remote <netrom-hostname>:1235
784 GDB now includes support for the Apple Macintosh, as a host only. It
785 may be run as either an MPW tool or as a standalone application, and
786 it can debug through the serial port. All the usual GDB commands are
787 available, but to the target command, you must supply "serial" as the
788 device type instead of "/dev/ttyXX". See mpw-README in the main
789 directory for more information on how to build. The MPW configuration
790 scripts */mpw-config.in support only a few targets, and only the
791 mips-idt-ecoff target has been tested.
795 GDB configuration now uses autoconf. This is not user-visible,
796 but does simplify configuration and building.
800 GDB now supports hpux10.
802 *** Changes in GDB-4.14:
804 * New native configurations
806 x86 FreeBSD i[345]86-*-freebsd
807 x86 NetBSD i[345]86-*-netbsd
808 NS32k NetBSD ns32k-*-netbsd
809 Sparc NetBSD sparc-*-netbsd
813 A29K VxWorks a29k-*-vxworks
814 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
815 CPU32 EST-300 emulator m68*-*-est*
816 PowerPC ELF powerpc-*-elf
819 * Alpha OSF/1 support for procfs
821 GDB now supports procfs under OSF/1-2.x and higher, which makes it
822 possible to attach to running processes. As the mounting of the /proc
823 filesystem is optional on the Alpha, GDB automatically determines
824 the availability of /proc during startup. This can lead to problems
825 if /proc is unmounted after GDB has been started.
827 * Arguments to user-defined commands
829 User commands may accept up to 10 arguments separated by whitespace.
830 Arguments are accessed within the user command via $arg0..$arg9. A
833 print $arg0 + $arg1 + $arg2
835 To execute the command use:
838 Defines the command "adder" which prints the sum of its three arguments.
839 Note the arguments are text substitutions, so they may reference variables,
840 use complex expressions, or even perform inferior function calls.
842 * New `if' and `while' commands
844 This makes it possible to write more sophisticated user-defined
845 commands. Both commands take a single argument, which is the
846 expression to evaluate, and must be followed by the commands to
847 execute, one per line, if the expression is nonzero, the list being
848 terminated by the word `end'. The `if' command list may include an
849 `else' word, which causes the following commands to be executed only
850 if the expression is zero.
852 * Fortran source language mode
854 GDB now includes partial support for Fortran 77. It will recognize
855 Fortran programs and can evaluate a subset of Fortran expressions, but
856 variables and functions may not be handled correctly. GDB will work
857 with G77, but does not yet know much about symbols emitted by other
860 * Better HPUX support
862 Most debugging facilities now work on dynamic executables for HPPAs
863 running hpux9 or later. You can attach to running dynamically linked
864 processes, but by default the dynamic libraries will be read-only, so
865 for instance you won't be able to put breakpoints in them. To change
866 that behavior do the following before running the program:
872 This will cause the libraries to be mapped private and read-write.
873 To revert to the normal behavior, do this:
879 You cannot set breakpoints or examine data in the library until after
880 the library is loaded if the function/data symbols do not have
883 GDB can now also read debug symbols produced by the HP C compiler on
884 HPPAs (sorry, no C++, Fortran or 68k support).
886 * Target byte order now dynamically selectable
888 You can choose which byte order to use with a target system, via the
889 commands "set endian big" and "set endian little", and you can see the
890 current setting by using "show endian". You can also give the command
891 "set endian auto", in which case GDB will use the byte order
892 associated with the executable. Currently, only embedded MIPS
893 configurations support dynamic selection of target byte order.
895 * New DOS host serial code
897 This version uses DPMI interrupts to handle buffered I/O, so you
898 no longer need to run asynctsr when debugging boards connected to
901 *** Changes in GDB-4.13:
903 * New "complete" command
905 This lists all the possible completions for the rest of the line, if it
906 were to be given as a command itself. This is intended for use by emacs.
908 * Trailing space optional in prompt
910 "set prompt" no longer adds a space for you after the prompt you set. This
911 allows you to set a prompt which ends in a space or one that does not.
913 * Breakpoint hit counts
915 "info break" now displays a count of the number of times the breakpoint
916 has been hit. This is especially useful in conjunction with "ignore"; you
917 can ignore a large number of breakpoint hits, look at the breakpoint info
918 to see how many times the breakpoint was hit, then run again, ignoring one
919 less than that number, and this will get you quickly to the last hit of
922 * Ability to stop printing at NULL character
924 "set print null-stop" will cause GDB to stop printing the characters of
925 an array when the first NULL is encountered. This is useful when large
926 arrays actually contain only short strings.
928 * Shared library breakpoints
930 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
931 breakpoints in shared libraries before the executable is run.
933 * Hardware watchpoints
935 There is a new hardware breakpoint for the watch command for sparclite
936 targets. See gdb/sparclite/hw_breakpoint.note.
938 Hardware watchpoints are also now supported under Linux.
942 Annotations have been added. These are for use with graphical interfaces,
943 and are still experimental. Currently only gdba.el uses these.
945 * Improved Irix 5 support
947 GDB now works properly with Irix 5.2.
949 * Improved HPPA support
951 GDB now works properly with the latest GCC and GAS.
953 * New native configurations
955 Sequent PTX4 i[34]86-sequent-ptx4
956 HPPA running OSF/1 hppa*-*-osf*
957 Atari TT running SVR4 m68*-*-sysv4*
958 RS/6000 LynxOS rs6000-*-lynxos*
962 OS/9000 i[34]86-*-os9k
963 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
966 * Hitachi SH7000 and E7000-PC ICE support
968 There is now support for communicating with the Hitachi E7000-PC ICE.
969 This is available automatically when GDB is configured for the SH.
973 As usual, a variety of small fixes and improvements, both generic
974 and configuration-specific. See the ChangeLog for more detail.
976 *** Changes in GDB-4.12:
978 * Irix 5 is now supported
982 GDB-4.12 on the HPPA has a number of changes which make it unable
983 to debug the output from the currently released versions of GCC and
984 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
985 of GCC and GAS, versions of these tools designed to work with GDB-4.12
986 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
989 *** Changes in GDB-4.11:
991 * User visible changes:
995 The "set remotedebug" option is now consistent between the mips remote
996 target, remote targets using the gdb-specific protocol, UDI (AMD's
997 debug protocol for the 29k) and the 88k bug monitor. It is now an
998 integer specifying a debug level (normally 0 or 1, but 2 means more
999 debugging info for the mips target).
1001 * DEC Alpha native support
1003 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
1004 debug info, but GDB works fairly well with the DEC compiler and should
1005 work with a future GCC release. See the README file for a few
1006 Alpha-specific notes.
1008 * Preliminary thread implementation
1010 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
1012 * LynxOS native and target support for 386
1014 This release has been hosted on LynxOS 2.2, and also can be configured
1015 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
1018 * Improvements in C++ mangling/demangling.
1020 This release has much better g++ debugging, specifically in name
1021 mangling/demangling, virtual function calls, print virtual table,
1022 call methods, ...etc.
1024 *** Changes in GDB-4.10:
1026 * User visible changes:
1028 Remote debugging using the GDB-specific (`target remote') protocol now
1029 supports the `load' command. This is only useful if you have some
1030 other way of getting the stub to the target system, and you can put it
1031 somewhere in memory where it won't get clobbered by the download.
1033 Filename completion now works.
1035 When run under emacs mode, the "info line" command now causes the
1036 arrow to point to the line specified. Also, "info line" prints
1037 addresses in symbolic form (as well as hex).
1039 All vxworks based targets now support a user settable option, called
1040 vxworks-timeout. This option represents the number of seconds gdb
1041 should wait for responses to rpc's. You might want to use this if
1042 your vxworks target is, perhaps, a slow software simulator or happens
1043 to be on the far side of a thin network line.
1047 This release contains support for using a DEC alpha as a GDB host for
1048 cross debugging. Native alpha debugging is not supported yet.
1051 *** Changes in GDB-4.9:
1055 This is the first GDB release which is accompanied by a matching testsuite.
1056 The testsuite requires installation of dejagnu, which should be available
1057 via ftp from most sites that carry GNU software.
1061 'Cfront' style demangling has had its name changed to 'ARM' style, to
1062 emphasize that it was written from the specifications in the C++ Annotated
1063 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
1064 disclaimers, it still generated too much confusion with users attempting to
1065 use gdb with AT&T cfront.
1069 GDB now uses a standard remote interface to a simulator library.
1070 So far, the library contains simulators for the Zilog Z8001/2, the
1071 Hitachi H8/300, H8/500 and Super-H.
1073 * New targets supported
1075 H8/300 simulator h8300-hitachi-hms or h8300hms
1076 H8/500 simulator h8500-hitachi-hms or h8500hms
1077 SH simulator sh-hitachi-hms or sh
1078 Z8000 simulator z8k-zilog-none or z8ksim
1079 IDT MIPS board over serial line mips-idt-ecoff
1081 Cross-debugging to GO32 targets is supported. It requires a custom
1082 version of the i386-stub.c module which is integrated with the
1083 GO32 memory extender.
1085 * New remote protocols
1087 MIPS remote debugging protocol.
1089 * New source languages supported
1091 This version includes preliminary support for Chill, a Pascal like language
1092 used by telecommunications companies. Chill support is also being integrated
1093 into the GNU compiler, but we don't know when it will be publically available.
1096 *** Changes in GDB-4.8:
1098 * HP Precision Architecture supported
1100 GDB now supports HP PA-RISC machines running HPUX. A preliminary
1101 version of this support was available as a set of patches from the
1102 University of Utah. GDB does not support debugging of programs
1103 compiled with the HP compiler, because HP will not document their file
1104 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
1105 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
1107 Many problems in the preliminary version have been fixed.
1109 * Faster and better demangling
1111 We have improved template demangling and fixed numerous bugs in the GNU style
1112 demangler. It can now handle type modifiers such as `static' or `const'. Wide
1113 character types (wchar_t) are now supported. Demangling of each symbol is now
1114 only done once, and is cached when the symbol table for a file is read in.
1115 This results in a small increase in memory usage for C programs, a moderate
1116 increase in memory usage for C++ programs, and a fantastic speedup in
1119 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
1120 from the specifications in the Annotated Reference Manual, which AT&T's
1121 compiler does not actually implement.
1123 * G++ multiple inheritance compiler problem
1125 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
1126 inheritance lattices was reworked to properly discover ambiguities. We
1127 recently found an example which causes this new algorithm to fail in a
1128 very subtle way, producing bad debug information for those classes.
1129 The file 'gcc.patch' (in this directory) can be applied to gcc to
1130 circumvent the problem. A future GCC release will contain a complete
1133 The previous G++ debug info problem (mentioned below for the gdb-4.7
1134 release) is fixed in gcc version 2.3.2.
1136 * Improved configure script
1138 The `configure' script will now attempt to guess your system type if
1139 you don't supply a host system type. The old scheme of supplying a
1140 host system triplet is preferable over using this. All the magic is
1141 done in the new `config.guess' script. Examine it for details.
1143 We have also brought our configure script much more in line with the FSF's
1144 version. It now supports the --with-xxx options. In particular,
1145 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
1146 The resulting GDB will not be able to read arbitrary object file formats --
1147 only the format ``expected'' to be used on the configured target system.
1148 We hope to make this the default in a future release.
1150 * Documentation improvements
1152 There's new internal documentation on how to modify GDB, and how to
1153 produce clean changes to the code. We implore people to read it
1154 before submitting changes.
1156 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
1157 M4 macros. The new texinfo.tex is provided in this release. Pre-built
1158 `info' files are also provided. To build `info' files from scratch,
1159 you will need the latest `makeinfo' release, which will be available in
1160 a future texinfo-X.Y release.
1162 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
1163 We're not sure exactly which versions have this problem, but it has
1164 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
1165 or better. If that isn't possible, there is a patch in
1166 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
1167 around this problem.
1171 GDB now supports array constants that can be used in expressions typed in by
1172 the user. The syntax is `{element, element, ...}'. Ie: you can now type
1173 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
1176 The new directory `gdb/sparclite' contains a program that demonstrates
1177 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
1179 * New native hosts supported
1181 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
1182 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
1184 * New targets supported
1186 AMD 29k family via UDI a29k-amd-udi or udi29k
1188 * New file formats supported
1190 BFD now supports reading HP/PA-RISC executables (SOM file format?),
1191 HPUX core files, and SCO 3.2v2 core files.
1195 Attaching to processes now works again; thanks for the many bug reports.
1197 We have also stomped on a bunch of core dumps caused by
1198 printf_filtered("%s") problems.
1200 We eliminated a copyright problem on the rpc and ptrace header files
1201 for VxWorks, which was discovered at the last minute during the 4.7
1202 release. You should now be able to build a VxWorks GDB.
1204 You can now interrupt gdb while an attached process is running. This
1205 will cause the attached process to stop, and give control back to GDB.
1207 We fixed problems caused by using too many file descriptors
1208 for reading symbols from object files and libraries. This was
1209 especially a problem for programs that used many (~100) shared
1212 The `step' command now only enters a subroutine if there is line number
1213 information for the subroutine. Otherwise it acts like the `next'
1214 command. Previously, `step' would enter subroutines if there was
1215 any debugging information about the routine. This avoids problems
1216 when using `cc -g1' on MIPS machines.
1218 * Internal improvements
1220 GDB's internal interfaces have been improved to make it easier to support
1221 debugging of multiple languages in the future.
1223 GDB now uses a common structure for symbol information internally.
1224 Minimal symbols (derived from linkage symbols in object files), partial
1225 symbols (from a quick scan of debug information), and full symbols
1226 contain a common subset of information, making it easier to write
1227 shared code that handles any of them.
1229 * New command line options
1231 We now accept --silent as an alias for --quiet.
1235 The memory-mapped-malloc library is now licensed under the GNU Library
1236 General Public License.
1238 *** Changes in GDB-4.7:
1240 * Host/native/target split
1242 GDB has had some major internal surgery to untangle the support for
1243 hosts and remote targets. Now, when you configure GDB for a remote
1244 target, it will no longer load in all of the support for debugging
1245 local programs on the host. When fully completed and tested, this will
1246 ensure that arbitrary host/target combinations are possible.
1248 The primary conceptual shift is to separate the non-portable code in
1249 GDB into three categories. Host specific code is required any time GDB
1250 is compiled on that host, regardless of the target. Target specific
1251 code relates to the peculiarities of the target, but can be compiled on
1252 any host. Native specific code is everything else: it can only be
1253 built when the host and target are the same system. Child process
1254 handling and core file support are two common `native' examples.
1256 GDB's use of /proc for controlling Unix child processes is now cleaner.
1257 It has been split out into a single module under the `target_ops' vector,
1258 plus two native-dependent functions for each system that uses /proc.
1260 * New hosts supported
1262 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
1263 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1264 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
1266 * New targets supported
1268 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1269 68030 and CPU32 m68030-*-*, m68332-*-*
1271 * New native hosts supported
1273 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1274 (386bsd is not well tested yet)
1275 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
1277 * New file formats supported
1279 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
1280 supports reading of `a.out.adobe' object files, which are an a.out
1281 format extended with minimal information about multiple sections.
1285 `show copying' is the same as the old `info copying'.
1286 `show warranty' is the same as `info warrantee'.
1287 These were renamed for consistency. The old commands continue to work.
1289 `info handle' is a new alias for `info signals'.
1291 You can now define pre-command hooks, which attach arbitrary command
1292 scripts to any command. The commands in the hook will be executed
1293 prior to the user's command. You can also create a hook which will be
1294 executed whenever the program stops. See gdb.texinfo.
1298 We now deal with Cfront style name mangling, and can even extract type
1299 info from mangled symbols. GDB can automatically figure out which
1300 symbol mangling style your C++ compiler uses.
1302 Calling of methods and virtual functions has been improved as well.
1306 The crash that occured when debugging Sun Ansi-C compiled binaries is
1307 fixed. This was due to mishandling of the extra N_SO stabs output
1310 We also finally got Ultrix 4.2 running in house, and fixed core file
1311 support, with help from a dozen people on the net.
1313 John M. Farrell discovered that the reason that single-stepping was so
1314 slow on all of the Mips based platforms (primarily SGI and DEC) was
1315 that we were trying to demangle and lookup a symbol used for internal
1316 purposes on every instruction that was being stepped through. Changing
1317 the name of that symbol so that it couldn't be mistaken for a C++
1318 mangled symbol sped things up a great deal.
1320 Rich Pixley sped up symbol lookups in general by getting much smarter
1321 about when C++ symbol mangling is necessary. This should make symbol
1322 completion (TAB on the command line) much faster. It's not as fast as
1323 we'd like, but it's significantly faster than gdb-4.6.
1327 A new user controllable variable 'call_scratch_address' can
1328 specify the location of a scratch area to be used when GDB
1329 calls a function in the target. This is necessary because the
1330 usual method of putting the scratch area on the stack does not work
1331 in systems that have separate instruction and data spaces.
1333 We integrated changes to support the 29k UDI (Universal Debugger
1334 Interface), but discovered at the last minute that we didn't have all
1335 of the appropriate copyright paperwork. We are working with AMD to
1336 resolve this, and hope to have it available soon.
1340 We have sped up the remote serial line protocol, especially for targets
1341 with lots of registers. It now supports a new `expedited status' ('T')
1342 message which can be used in place of the existing 'S' status message.
1343 This allows the remote stub to send only the registers that GDB
1344 needs to make a quick decision about single-stepping or conditional
1345 breakpoints, eliminating the need to fetch the entire register set for
1346 each instruction being stepped through.
1348 The GDB remote serial protocol now implements a write-through cache for
1349 registers, only re-reading the registers if the target has run.
1351 There is also a new remote serial stub for SPARC processors. You can
1352 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
1353 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
1354 processor with a serial port.
1358 Configure.in files have become much easier to read and modify. A new
1359 `table driven' format makes it more obvious what configurations are
1360 supported, and what files each one uses.
1364 There is a new opcodes library which will eventually contain all of the
1365 disassembly routines and opcode tables. At present, it only contains
1366 Sparc and Z8000 routines. This will allow the assembler, debugger, and
1367 disassembler (binutils/objdump) to share these routines.
1369 The libiberty library is now copylefted under the GNU Library General
1370 Public License. This allows more liberal use, and was done so libg++
1371 can use it. This makes no difference to GDB, since the Library License
1372 grants all the rights from the General Public License.
1376 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
1377 reference to the stabs symbol info used by the debugger. It is (as far
1378 as we know) the only published document on this fascinating topic. We
1379 encourage you to read it, compare it to the stabs information on your
1380 system, and send improvements on the document in general (to
1381 bug-gdb@prep.ai.mit.edu).
1383 And, of course, many bugs have been fixed.
1386 *** Changes in GDB-4.6:
1388 * Better support for C++ function names
1390 GDB now accepts as input the "demangled form" of C++ overloaded function
1391 names and member function names, and can do command completion on such names
1392 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
1393 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
1394 Make use of command completion, it is your friend.
1396 GDB also now accepts a variety of C++ mangled symbol formats. They are
1397 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
1398 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
1399 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
1400 for the list of formats.
1402 * G++ symbol mangling problem
1404 Recent versions of gcc have a bug in how they emit debugging information for
1405 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
1406 directory) can be applied to gcc to fix the problem. Alternatively, if you
1407 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
1408 usual symptom is difficulty with setting breakpoints on methods. GDB complains
1409 about the method being non-existent. (We believe that version 2.2.2 of GCC has
1412 * New 'maintenance' command
1414 All of the commands related to hacking GDB internals have been moved out of
1415 the main command set, and now live behind the 'maintenance' command. This
1416 can also be abbreviated as 'mt'. The following changes were made:
1418 dump-me -> maintenance dump-me
1419 info all-breakpoints -> maintenance info breakpoints
1420 printmsyms -> maintenance print msyms
1421 printobjfiles -> maintenance print objfiles
1422 printpsyms -> maintenance print psymbols
1423 printsyms -> maintenance print symbols
1425 The following commands are new:
1427 maintenance demangle Call internal GDB demangler routine to
1428 demangle a C++ link name and prints the result.
1429 maintenance print type Print a type chain for a given symbol
1431 * Change to .gdbinit file processing
1433 We now read the $HOME/.gdbinit file before processing the argv arguments
1434 (e.g. reading symbol files or core files). This allows global parameters to
1435 be set, which will apply during the symbol reading. The ./.gdbinit is still
1436 read after argv processing.
1438 * New hosts supported
1440 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
1442 Linux support i386-unknown-linux or linux
1444 We are also including code to support the HP/PA running BSD and HPUX. This
1445 is almost guaranteed not to work, as we didn't have time to test or build it
1446 for this release. We are including it so that the more adventurous (or
1447 masochistic) of you can play with it. We also had major problems with the
1448 fact that the compiler that we got from HP doesn't support the -g option.
1451 * New targets supported
1453 Hitachi H8/300 h8300-hitachi-hms or h8300hms
1455 * More smarts about finding #include files
1457 GDB now remembers the compilation directory for all include files, and for
1458 all files from which C is generated (like yacc and lex sources). This
1459 greatly improves GDB's ability to find yacc/lex sources, and include files,
1460 especially if you are debugging your program from a directory different from
1461 the one that contains your sources.
1463 We also fixed a bug which caused difficulty with listing and setting
1464 breakpoints in include files which contain C code. (In the past, you had to
1465 try twice in order to list an include file that you hadn't looked at before.)
1467 * Interesting infernals change
1469 GDB now deals with arbitrary numbers of sections, where the symbols for each
1470 section must be relocated relative to that section's landing place in the
1471 target's address space. This work was needed to support ELF with embedded
1472 stabs used by Solaris-2.0.
1474 * Bug fixes (of course!)
1476 There have been loads of fixes for the following things:
1477 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
1478 i960, stabs, DOS(GO32), procfs, etc...
1480 See the ChangeLog for details.
1482 *** Changes in GDB-4.5:
1484 * New machines supported (host and target)
1486 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
1488 SGI Irix-4.x mips-sgi-irix4 or iris4
1490 * New malloc package
1492 GDB now uses a new memory manager called mmalloc, based on gmalloc.
1493 Mmalloc is capable of handling mutiple heaps of memory. It is also
1494 capable of saving a heap to a file, and then mapping it back in later.
1495 This can be used to greatly speedup the startup of GDB by using a
1496 pre-parsed symbol table which lives in a mmalloc managed heap. For
1497 more details, please read mmalloc/mmalloc.texi.
1501 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
1502 'help info proc' for details.
1504 * MIPS ecoff symbol table format
1506 The code that reads MIPS symbol table format is now supported on all hosts.
1507 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
1510 * File name changes for MS-DOS
1512 Many files in the config directories have been renamed to make it easier to
1513 support GDB on MS-DOSe systems (which have very restrictive file name
1514 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
1515 environment) is close to working but has some remaining problems. Note
1516 that debugging of DOS programs is not supported, due to limitations
1517 in the ``operating system'', but it can be used to host cross-debugging.
1519 * Cross byte order fixes
1521 Many fixes have been made to support cross debugging of Sparc and MIPS
1522 targets from hosts whose byte order differs.
1524 * New -mapped and -readnow options
1526 If memory-mapped files are available on your system through the 'mmap'
1527 system call, you can use the -mapped option on the `file' or
1528 `symbol-file' commands to cause GDB to write the symbols from your
1529 program into a reusable file. If the program you are debugging is
1530 called `/path/fred', the mapped symbol file will be `./fred.syms'.
1531 Future GDB debugging sessions will notice the presence of this file,
1532 and will quickly map in symbol information from it, rather than reading
1533 the symbol table from the executable program. Using the '-mapped'
1534 option in a GDB `file' or `symbol-file' command has the same effect as
1535 starting GDB with the '-mapped' command-line option.
1537 You can cause GDB to read the entire symbol table immediately by using
1538 the '-readnow' option with any of the commands that load symbol table
1539 information (or on the GDB command line). This makes the command
1540 slower, but makes future operations faster.
1542 The -mapped and -readnow options are typically combined in order to
1543 build a `fred.syms' file that contains complete symbol information.
1544 A simple GDB invocation to do nothing but build a `.syms' file for future
1547 gdb -batch -nx -mapped -readnow programname
1549 The `.syms' file is specific to the host machine on which GDB is run.
1550 It holds an exact image of GDB's internal symbol table. It cannot be
1551 shared across multiple host platforms.
1553 * longjmp() handling
1555 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
1556 siglongjmp() without losing control. This feature has not yet been ported to
1557 all systems. It currently works on many 386 platforms, all MIPS-based
1558 platforms (SGI, DECstation, etc), and Sun3/4.
1562 Preliminary work has been put in to support the new Solaris OS from Sun. At
1563 this time, it can control and debug processes, but it is not capable of
1568 As always, many many bug fixes. The major areas were with g++, and mipsread.
1569 People using the MIPS-based platforms should experience fewer mysterious
1570 crashes and trashed symbol tables.
1572 *** Changes in GDB-4.4:
1574 * New machines supported (host and target)
1576 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1578 BSD Reno on Vax vax-dec-bsd
1579 Ultrix on Vax vax-dec-ultrix
1581 * New machines supported (target)
1583 AMD 29000 embedded, using EBMON a29k-none-none
1587 GDB continues to improve its handling of C++. `References' work better.
1588 The demangler has also been improved, and now deals with symbols mangled as
1589 per the Annotated C++ Reference Guide.
1591 GDB also now handles `stabs' symbol information embedded in MIPS
1592 `ecoff' symbol tables. Since the ecoff format was not easily
1593 extensible to handle new languages such as C++, this appeared to be a
1594 good way to put C++ debugging info into MIPS binaries. This option
1595 will be supported in the GNU C compiler, version 2, when it is
1598 * New features for SVR4
1600 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
1601 shared libraries. Debugging dynamically linked programs should present
1602 only minor differences from debugging statically linked programs.
1604 The `info proc' command will print out information about any process
1605 on an SVR4 system (including the one you are debugging). At the moment,
1606 it prints the address mappings of the process.
1608 If you bring up GDB on another SVR4 system, please send mail to
1609 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
1611 * Better dynamic linking support in SunOS
1613 Reading symbols from shared libraries which contain debugging symbols
1614 now works properly. However, there remain issues such as automatic
1615 skipping of `transfer vector' code during function calls, which
1616 make it harder to debug code in a shared library, than to debug the
1617 same code linked statically.
1621 GDB is now using the latest `getopt' routines from the FSF. This
1622 version accepts the -- prefix for options with long names. GDB will
1623 continue to accept the old forms (-option and +option) as well.
1624 Various single letter abbreviations for options have been explicity
1625 added to the option table so that they won't get overshadowed in the
1626 future by other options that begin with the same letter.
1630 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
1631 Many assorted bugs have been handled. Many more remain to be handled.
1632 See the various ChangeLog files (primarily in gdb and bfd) for details.
1635 *** Changes in GDB-4.3:
1637 * New machines supported (host and target)
1639 Amiga 3000 running Amix m68k-cbm-svr4 or amix
1640 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
1641 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1643 * Almost SCO Unix support
1645 We had hoped to support:
1646 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1647 (except for core file support), but we discovered very late in the release
1648 that it has problems with process groups that render gdb unusable. Sorry
1649 about that. I encourage people to fix it and post the fixes.
1651 * Preliminary ELF and DWARF support
1653 GDB can read ELF object files on System V Release 4, and can handle
1654 debugging records for C, in DWARF format, in ELF files. This support
1655 is preliminary. If you bring up GDB on another SVR4 system, please
1656 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
1661 GDB now uses the latest `readline' library. One user-visible change
1662 is that two tabs will list possible command completions, which previously
1663 required typing M-? (meta-question mark, or ESC ?).
1667 The `stepi' bug that many of you noticed has been squashed.
1668 Many bugs in C++ have been handled. Many more remain to be handled.
1669 See the various ChangeLog files (primarily in gdb and bfd) for details.
1671 * State of the MIPS world (in case you wondered):
1673 GDB can understand the symbol tables emitted by the compilers
1674 supplied by most vendors of MIPS-based machines, including DEC. These
1675 symbol tables are in a format that essentially nobody else uses.
1677 Some versions of gcc come with an assembler post-processor called
1678 mips-tfile. This program is required if you want to do source-level
1679 debugging of gcc-compiled programs. I believe FSF does not ship
1680 mips-tfile with gcc version 1, but it will eventually come with gcc
1683 Debugging of g++ output remains a problem. g++ version 1.xx does not
1684 really support it at all. (If you're lucky, you should be able to get
1685 line numbers and stack traces to work, but no parameters or local
1686 variables.) With some work it should be possible to improve the
1689 When gcc version 2 is released, you will have somewhat better luck.
1690 However, even then you will get confusing results for inheritance and
1693 We will eventually provide full debugging of g++ output on
1694 DECstations. This will probably involve some kind of stabs-in-ecoff
1695 encapulation, but the details have not been worked out yet.
1698 *** Changes in GDB-4.2:
1700 * Improved configuration
1702 Only one copy of `configure' exists now, and it is not self-modifying.
1703 Porting BFD is simpler.
1707 The `step' and `next' commands now only stop at the first instruction
1708 of a source line. This prevents the multiple stops that used to occur
1709 in switch statements, for-loops, etc. `Step' continues to stop if a
1710 function that has debugging information is called within the line.
1714 Lots of small bugs fixed. More remain.
1716 * New host supported (not target)
1718 Intel 386 PC clone running Mach i386-none-mach
1721 *** Changes in GDB-4.1:
1723 * Multiple source language support
1725 GDB now has internal scaffolding to handle several source languages.
1726 It determines the type of each source file from its filename extension,
1727 and will switch expression parsing and number formatting to match the
1728 language of the function in the currently selected stack frame.
1729 You can also specifically set the language to be used, with
1730 `set language c' or `set language modula-2'.
1734 GDB now has preliminary support for the GNU Modula-2 compiler,
1735 currently under development at the State University of New York at
1736 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
1737 continue through the fall of 1991 and into 1992.
1739 Other Modula-2 compilers are currently not supported, and attempting to
1740 debug programs compiled with them will likely result in an error as the
1741 symbol table is read. Feel free to work on it, though!
1743 There are hooks in GDB for strict type checking and range checking,
1744 in the `Modula-2 philosophy', but they do not currently work.
1748 GDB can now write to executable and core files (e.g. patch
1749 a variable's value). You must turn this switch on, specify
1750 the file ("exec foo" or "core foo"), *then* modify it, e.g.
1751 by assigning a new value to a variable. Modifications take
1754 * Automatic SunOS shared library reading
1756 When you run your program, GDB automatically determines where its
1757 shared libraries (if any) have been loaded, and reads their symbols.
1758 The `share' command is no longer needed. This also works when
1759 examining core files.
1763 You can specify the number of lines that the `list' command shows.
1766 * New machines supported (host and target)
1768 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1769 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
1770 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
1772 * New hosts supported (not targets)
1774 IBM RT/PC: romp-ibm-aix or rtpc
1776 * New targets supported (not hosts)
1778 AMD 29000 embedded with COFF a29k-none-coff
1779 AMD 29000 embedded with a.out a29k-none-aout
1780 Ultracomputer remote kernel debug a29k-nyu-kern
1782 * New remote interfaces
1788 *** Changes in GDB-4.0:
1792 Wide output is wrapped at good places to make the output more readable.
1794 Gdb now supports cross-debugging from a host machine of one type to a
1795 target machine of another type. Communication with the target system
1796 is over serial lines. The ``target'' command handles connecting to the
1797 remote system; the ``load'' command will download a program into the
1798 remote system. Serial stubs for the m68k and i386 are provided. Gdb
1799 also supports debugging of realtime processes running under VxWorks,
1800 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
1801 stub on the target system.
1803 New CPUs supported include the AMD 29000 and Intel 960.
1805 GDB now reads object files and symbol tables via a ``binary file''
1806 library, which allows a single copy of GDB to debug programs of multiple
1807 object file types such as a.out and coff.
1809 There is now a GDB reference card in "doc/refcard.tex". (Make targets
1810 refcard.dvi and refcard.ps are available to format it).
1813 * Control-Variable user interface simplified
1815 All variables that control the operation of the debugger can be set
1816 by the ``set'' command, and displayed by the ``show'' command.
1818 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
1819 ``Show prompt'' produces the response:
1820 Gdb's prompt is new-gdb=>.
1822 What follows are the NEW set commands. The command ``help set'' will
1823 print a complete list of old and new set commands. ``help set FOO''
1824 will give a longer description of the variable FOO. ``show'' will show
1825 all of the variable descriptions and their current settings.
1827 confirm on/off: Enables warning questions for operations that are
1828 hard to recover from, e.g. rerunning the program while
1829 it is already running. Default is ON.
1831 editing on/off: Enables EMACS style command line editing
1832 of input. Previous lines can be recalled with
1833 control-P, the current line can be edited with control-B,
1834 you can search for commands with control-R, etc.
1837 history filename NAME: NAME is where the gdb command history
1838 will be stored. The default is .gdb_history,
1839 or the value of the environment variable
1842 history size N: The size, in commands, of the command history. The
1843 default is 256, or the value of the environment variable
1846 history save on/off: If this value is set to ON, the history file will
1847 be saved after exiting gdb. If set to OFF, the
1848 file will not be saved. The default is OFF.
1850 history expansion on/off: If this value is set to ON, then csh-like
1851 history expansion will be performed on
1852 command line input. The default is OFF.
1854 radix N: Sets the default radix for input and output. It can be set
1855 to 8, 10, or 16. Note that the argument to "radix" is interpreted
1856 in the current radix, so "set radix 10" is always a no-op.
1858 height N: This integer value is the number of lines on a page. Default
1859 is 24, the current `stty rows'' setting, or the ``li#''
1860 setting from the termcap entry matching the environment
1863 width N: This integer value is the number of characters on a line.
1864 Default is 80, the current `stty cols'' setting, or the ``co#''
1865 setting from the termcap entry matching the environment
1868 Note: ``set screensize'' is obsolete. Use ``set height'' and
1869 ``set width'' instead.
1871 print address on/off: Print memory addresses in various command displays,
1872 such as stack traces and structure values. Gdb looks
1873 more ``symbolic'' if you turn this off; it looks more
1874 ``machine level'' with it on. Default is ON.
1876 print array on/off: Prettyprint arrays. New convenient format! Default
1879 print demangle on/off: Print C++ symbols in "source" form if on,
1882 print asm-demangle on/off: Same, for assembler level printouts
1885 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
1888 * Support for Epoch Environment.
1890 The epoch environment is a version of Emacs v18 with windowing. One
1891 new command, ``inspect'', is identical to ``print'', except that if you
1892 are running in the epoch environment, the value is printed in its own
1896 * Support for Shared Libraries
1898 GDB can now debug programs and core files that use SunOS shared libraries.
1899 Symbols from a shared library cannot be referenced
1900 before the shared library has been linked with the program (this
1901 happens after you type ``run'' and before the function main() is entered).
1902 At any time after this linking (including when examining core files
1903 from dynamically linked programs), gdb reads the symbols from each
1904 shared library when you type the ``sharedlibrary'' command.
1905 It can be abbreviated ``share''.
1907 sharedlibrary REGEXP: Load shared object library symbols for files
1908 matching a unix regular expression. No argument
1909 indicates to load symbols for all shared libraries.
1911 info sharedlibrary: Status of loaded shared libraries.
1916 A watchpoint stops execution of a program whenever the value of an
1917 expression changes. Checking for this slows down execution
1918 tremendously whenever you are in the scope of the expression, but is
1919 quite useful for catching tough ``bit-spreader'' or pointer misuse
1920 problems. Some machines such as the 386 have hardware for doing this
1921 more quickly, and future versions of gdb will use this hardware.
1923 watch EXP: Set a watchpoint (breakpoint) for an expression.
1925 info watchpoints: Information about your watchpoints.
1927 delete N: Deletes watchpoint number N (same as breakpoints).
1928 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
1929 enable N: Re-enables watchpoint number N (same as breakpoints).
1932 * C++ multiple inheritance
1934 When used with a GCC version 2 compiler, GDB supports multiple inheritance
1937 * C++ exception handling
1939 Gdb now supports limited C++ exception handling. Besides the existing
1940 ability to breakpoint on an exception handler, gdb can breakpoint on
1941 the raising of an exception (before the stack is peeled back to the
1944 catch FOO: If there is a FOO exception handler in the dynamic scope,
1945 set a breakpoint to catch exceptions which may be raised there.
1946 Multiple exceptions (``catch foo bar baz'') may be caught.
1948 info catch: Lists all exceptions which may be caught in the
1949 current stack frame.
1952 * Minor command changes
1954 The command ``call func (arg, arg, ...)'' now acts like the print
1955 command, except it does not print or save a value if the function's result
1956 is void. This is similar to dbx usage.
1958 The ``up'' and ``down'' commands now always print the frame they end up
1959 at; ``up-silently'' and `down-silently'' can be used in scripts to change
1960 frames without printing.
1962 * New directory command
1964 'dir' now adds directories to the FRONT of the source search path.
1965 The path starts off empty. Source files that contain debug information
1966 about the directory in which they were compiled can be found even
1967 with an empty path; Sun CC and GCC include this information. If GDB can't
1968 find your source file in the current directory, type "dir .".
1970 * Configuring GDB for compilation
1972 For normal use, type ``./configure host''. See README or gdb.texinfo
1975 GDB now handles cross debugging. If you are remotely debugging between
1976 two different machines, type ``./configure host -target=targ''.
1977 Host is the machine where GDB will run; targ is the machine
1978 where the program that you are debugging will run.