1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 5.1:
6 * New command "set trust-readonly-sections on[off]".
8 This command is a hint that tells gdb that read-only sections
9 really are read-only (ie. that their contents will not change).
10 In this mode, gdb will go to the object file rather than the
11 target to read memory from read-only sections (such as ".text").
12 This can be a significant performance improvement on some
13 (notably embedded) targets.
15 * New command "generate-core-file" (or "gcore").
17 This new gdb command allows the user to drop a core file of the child
18 process state at any time. So far it's been implemented only for
19 GNU/Linux and Solaris, but should be relatively easily ported to other
20 hosts. Argument is core file name (defaults to core.<pid>).
22 * New command line option
24 GDB now accepts --pid or -p followed by a process id.
26 * Change in command line behavior -- corefiles vs. process ids.
28 There is a subtle behavior in the way in which GDB handles
29 command line arguments. The first non-flag argument is always
30 a program to debug, but the second non-flag argument may either
31 be a corefile or a process id. Previously, GDB would attempt to
32 open the second argument as a corefile, and if that failed, would
33 issue a superfluous error message and then attempt to attach it as
34 a process. Now, if the second argument begins with a non-digit,
35 it will be treated as a corefile. If it begins with a digit,
36 GDB will attempt to attach it as a process, and if no such process
37 is found, will then attempt to open it as a corefile.
39 * Changes in ARM configurations.
41 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
42 configuration is fully multi-arch.
44 * New native configurations
46 ARM NetBSD arm*-*-netbsd*
47 x86 OpenBSD i[3456]86-*-openbsd*
48 AMD x86-64 running GNU/Linux x86_64-*-linux-*
49 Sparc64 running FreeBSD sparc64-*-freebsd*
53 Sanyo XStormy16 xstormy16-elf
55 * OBSOLETE configurations and files
57 Configurations that have been declared obsolete in this release have
58 been commented out. Unless there is activity to revive these
59 configurations, the next release of GDB will have their sources
62 AMD 29k family via UDI a29k-amd-udi, udi29k
63 A29K VxWorks a29k-*-vxworks
64 AMD 29000 embedded, using EBMON a29k-none-none
65 AMD 29000 embedded with COFF a29k-none-coff
66 AMD 29000 embedded with a.out a29k-none-aout
68 testsuite/gdb.hp/gdb.threads-hp/ directory
70 * REMOVED configurations and files
72 TI TMS320C80 tic80-*-*
74 PowerPC Solaris powerpcle-*-solaris*
75 PowerPC Windows NT powerpcle-*-cygwin32
76 PowerPC Netware powerpc-*-netware*
77 Harris/CXUX m88k m88*-harris-cxux*
78 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
79 ns32k-utek-sysv* ns32k-utek-*
80 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
81 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
82 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
83 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
84 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
86 * Changes to command line processing
88 The new `--args' feature can be used to specify command-line arguments
89 for the inferior from gdb's command line.
91 * Changes to key bindings
93 There is a new `operate-and-get-next' function bound to `C-o'.
95 *** Changes in GDB 5.1.1
97 Fix compile problem on DJGPP.
99 Fix a problem with floating-point registers on the i386 being
102 Fix to stop GDB crashing on .debug_str debug info.
104 Numerous documentation fixes.
106 Numerous testsuite fixes.
108 *** Changes in GDB 5.1:
110 * New native configurations
112 Alpha FreeBSD alpha*-*-freebsd*
113 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
114 MIPS GNU/Linux mips*-*-linux*
115 MIPS SGI Irix 6.x mips*-sgi-irix6*
117 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
121 Motorola 68HC11 and 68HC12 m68hc11-elf
123 UltraSparc running GNU/Linux sparc64-*-linux*
125 * OBSOLETE configurations and files
127 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
128 Harris/CXUX m88k m88*-harris-cxux*
129 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
130 ns32k-utek-sysv* ns32k-utek-*
131 TI TMS320C80 tic80-*-*
133 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
134 PowerPC Solaris powerpcle-*-solaris*
135 PowerPC Windows NT powerpcle-*-cygwin32
136 PowerPC Netware powerpc-*-netware*
137 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
138 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
139 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
140 Apple Macintosh (MPW) host N/A
142 stuff.c (Program to stuff files into a specially prepared space in kdb)
143 kdb-start.c (Main loop for the standalone kernel debugger)
145 Configurations that have been declared obsolete in this release have
146 been commented out. Unless there is activity to revive these
147 configurations, the next release of GDB will have their sources
150 * REMOVED configurations and files
152 Altos 3068 m68*-altos-*
153 Convex c1-*-*, c2-*-*
155 ARM RISCix arm-*-* (as host)
159 * GDB has been converted to ISO C.
161 GDB's source code has been converted to ISO C. In particular, the
162 sources are fully protoized, and rely on standard headers being
167 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
169 * The MI enabled by default.
171 The new machine oriented interface (MI) introduced in GDB 5.0 has been
172 revised and enabled by default. Packages which use GDB as a debugging
173 engine behind a UI or another front end are encouraged to switch to
174 using the GDB/MI interface, instead of the old annotations interface
175 which is now deprecated.
177 * Support for debugging Pascal programs.
179 GDB now includes support for debugging Pascal programs. The following
180 main features are supported:
182 - Pascal-specific data types such as sets;
184 - automatic recognition of Pascal sources based on file-name
187 - Pascal-style display of data types, variables, and functions;
189 - a Pascal expression parser.
191 However, some important features are not yet supported.
193 - Pascal string operations are not supported at all;
195 - there are some problems with boolean types;
197 - Pascal type hexadecimal constants are not supported
198 because they conflict with the internal variables format;
200 - support for Pascal objects and classes is not full yet;
202 - unlike Pascal, GDB is case-sensitive for symbol names.
204 * Changes in completion.
206 Commands such as `shell', `run' and `set args', which pass arguments
207 to inferior programs, now complete on file names, similar to what
208 users expect at the shell prompt.
210 Commands which accept locations, such as `disassemble', `print',
211 `breakpoint', `until', etc. now complete on filenames as well as
212 program symbols. Thus, if you type "break foob TAB", and the source
213 files linked into the programs include `foobar.c', that file name will
214 be one of the candidates for completion. However, file names are not
215 considered for completion after you typed a colon that delimits a file
216 name from a name of a function in that file, as in "break foo.c:bar".
218 `set demangle-style' completes on available demangling styles.
220 * New platform-independent commands:
222 It is now possible to define a post-hook for a command as well as a
223 hook that runs before the command. For more details, see the
224 documentation of `hookpost' in the GDB manual.
226 * Changes in GNU/Linux native debugging.
228 Support for debugging multi-threaded programs has been completely
229 revised for all platforms except m68k and sparc. You can now debug as
230 many threads as your system allows you to have.
232 Attach/detach is supported for multi-threaded programs.
234 Support for SSE registers was added for x86. This doesn't work for
235 multi-threaded programs though.
237 * Changes in MIPS configurations.
239 Multi-arch support is enabled for all MIPS configurations.
241 GDB can now be built as native debugger on SGI Irix 6.x systems for
242 debugging n32 executables. (Debugging 64-bit executables is not yet
245 * Unified support for hardware watchpoints in all x86 configurations.
247 Most (if not all) native x86 configurations support hardware-assisted
248 breakpoints and watchpoints in a unified manner. This support
249 implements debug register sharing between watchpoints, which allows to
250 put a virtually infinite number of watchpoints on the same address,
251 and also supports watching regions up to 16 bytes with several debug
254 The new maintenance command `maintenance show-debug-regs' toggles
255 debugging print-outs in functions that insert, remove, and test
256 watchpoints and hardware breakpoints.
258 * Changes in the DJGPP native configuration.
260 New command ``info dos sysinfo'' displays assorted information about
261 the CPU, OS, memory, and DPMI server.
263 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
264 display information about segment descriptors stored in GDT, LDT, and
267 New commands ``info dos pde'' and ``info dos pte'' display entries
268 from Page Directory and Page Tables (for now works with CWSDPMI only).
269 New command ``info dos address-pte'' displays the Page Table entry for
270 a given linear address.
272 GDB can now pass command lines longer than 126 characters to the
273 program being debugged (requires an update to the libdbg.a library
274 which is part of the DJGPP development kit).
276 DWARF2 debug info is now supported.
278 It is now possible to `step' and `next' through calls to `longjmp'.
280 * Changes in documentation.
282 All GDB documentation was converted to GFDL, the GNU Free
283 Documentation License.
285 Tracepoints-related commands are now fully documented in the GDB
288 TUI, the Text-mode User Interface, is now documented in the manual.
290 Tracepoints-related commands are now fully documented in the GDB
293 The "GDB Internals" manual now has an index. It also includes
294 documentation of `ui_out' functions, GDB coding standards, x86
295 hardware watchpoints, and memory region attributes.
297 * GDB's version number moved to ``version.in''
299 The Makefile variable VERSION has been replaced by the file
300 ``version.in''. People creating GDB distributions should update the
301 contents of this file.
305 GUD support is now a standard part of the EMACS distribution.
307 *** Changes in GDB 5.0:
309 * Improved support for debugging FP programs on x86 targets
311 Unified and much-improved support for debugging floating-point
312 programs on all x86 targets. In particular, ``info float'' now
313 displays the FP registers in the same format on all x86 targets, with
314 greater level of detail.
316 * Improvements and bugfixes in hardware-assisted watchpoints
318 It is now possible to watch array elements, struct members, and
319 bitfields with hardware-assisted watchpoints. Data-read watchpoints
320 on x86 targets no longer erroneously trigger when the address is
323 * Improvements in the native DJGPP version of GDB
325 The distribution now includes all the scripts and auxiliary files
326 necessary to build the native DJGPP version on MS-DOS/MS-Windows
327 machines ``out of the box''.
329 The DJGPP version can now debug programs that use signals. It is
330 possible to catch signals that happened in the debuggee, deliver
331 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
332 would kill the program being debugged.) Programs that hook hardware
333 interrupts (keyboard, timer, etc.) can also be debugged.
335 It is now possible to debug DJGPP programs that redirect their
336 standard handles or switch them to raw (as opposed to cooked) mode, or
337 even close them. The command ``run < foo > bar'' works as expected,
338 and ``info terminal'' reports useful information about the debuggee's
339 terminal, including raw/cooked mode, redirection, etc.
341 The DJGPP version now uses termios functions for console I/O, which
342 enables debugging graphics programs. Interrupting GDB with Ctrl-C
345 DOS-style file names with drive letters are now fully supported by
348 It is now possible to debug DJGPP programs that switch their working
349 directory. It is also possible to rerun the debuggee any number of
350 times without restarting GDB; thus, you can use the same setup,
351 breakpoints, etc. for many debugging sessions.
353 * New native configurations
355 ARM GNU/Linux arm*-*-linux*
356 PowerPC GNU/Linux powerpc-*-linux*
360 Motorola MCore mcore-*-*
361 x86 VxWorks i[3456]86-*-vxworks*
362 PowerPC VxWorks powerpc-*-vxworks*
363 TI TMS320C80 tic80-*-*
365 * OBSOLETE configurations
367 Altos 3068 m68*-altos-*
368 Convex c1-*-*, c2-*-*
370 ARM RISCix arm-*-* (as host)
373 Configurations that have been declared obsolete will be commented out,
374 but the code will be left in place. If there is no activity to revive
375 these configurations before the next release of GDB, the sources will
376 be permanently REMOVED.
378 * Gould support removed
380 Support for the Gould PowerNode and NP1 has been removed.
382 * New features for SVR4
384 On SVR4 native platforms (such as Solaris), if you attach to a process
385 without first loading a symbol file, GDB will now attempt to locate and
386 load symbols from the running process's executable file.
388 * Many C++ enhancements
390 C++ support has been greatly improved. Overload resolution now works properly
391 in almost all cases. RTTI support is on the way.
393 * Remote targets can connect to a sub-program
395 A popen(3) style serial-device has been added. This device starts a
396 sub-process (such as a stand-alone simulator) and then communicates
397 with that. The sub-program to run is specified using the syntax
398 ``|<program> <args>'' vis:
400 (gdb) set remotedebug 1
401 (gdb) target extended-remote |mn10300-elf-sim program-args
403 * MIPS 64 remote protocol
405 A long standing bug in the mips64 remote protocol where by GDB
406 expected certain 32 bit registers (ex SR) to be transfered as 32
407 instead of 64 bits has been fixed.
409 The command ``set remote-mips64-transfers-32bit-regs on'' has been
410 added to provide backward compatibility with older versions of GDB.
412 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
414 The command ``set remotebinarydownload'' command has been replaced by
415 ``set remote X-packet''. Other commands in ``set remote'' family
416 include ``set remote P-packet''.
418 * Breakpoint commands accept ranges.
420 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
421 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
422 ``tracepoint passcount'' also accepts a range of tracepoints.
424 * ``apropos'' command added.
426 The ``apropos'' command searches through command names and
427 documentation strings, printing out matches, making it much easier to
428 try to find a command that does what you are looking for.
432 A new machine oriented interface (MI) has been added to GDB. This
433 interface is designed for debug environments running GDB as a separate
434 process. This is part of the long term libGDB project. See the
435 "GDB/MI" chapter of the GDB manual for further information. It can be
436 enabled by configuring with:
438 .../configure --enable-gdbmi
440 *** Changes in GDB-4.18:
442 * New native configurations
444 HP-UX 10.20 hppa*-*-hpux10.20
445 HP-UX 11.x hppa*-*-hpux11.0*
446 M68K GNU/Linux m68*-*-linux*
450 Fujitsu FR30 fr30-*-elf*
451 Intel StrongARM strongarm-*-*
452 Mitsubishi D30V d30v-*-*
454 * OBSOLETE configurations
456 Gould PowerNode, NP1 np1-*-*, pn-*-*
458 Configurations that have been declared obsolete will be commented out,
459 but the code will be left in place. If there is no activity to revive
460 these configurations before the next release of GDB, the sources will
461 be permanently REMOVED.
465 As a compatibility experiment, GDB's source files buildsym.h and
466 buildsym.c have been converted to pure standard C, no longer
467 containing any K&R compatibility code. We believe that all systems in
468 use today either come with a standard C compiler, or have a GCC port
469 available. If this is not true, please report the affected
470 configuration to bug-gdb@gnu.org immediately. See the README file for
471 information about getting a standard C compiler if you don't have one
476 GDB now uses readline 2.2.
478 * set extension-language
480 You can now control the mapping between filename extensions and source
481 languages by using the `set extension-language' command. For instance,
482 you can ask GDB to treat .c files as C++ by saying
483 set extension-language .c c++
484 The command `info extensions' lists all of the recognized extensions
485 and their associated languages.
487 * Setting processor type for PowerPC and RS/6000
489 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
490 you can use the `set processor' command to specify what variant of the
491 PowerPC family you are debugging. The command
495 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
496 following PowerPC and RS6000 variants:
498 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
499 rs6000 IBM RS6000 ("POWER") architecture, user-level view
501 403GC IBM PowerPC 403GC
502 505 Motorola PowerPC 505
503 860 Motorola PowerPC 860 or 850
504 601 Motorola PowerPC 601
505 602 Motorola PowerPC 602
506 603 Motorola/IBM PowerPC 603 or 603e
507 604 Motorola PowerPC 604 or 604e
508 750 Motorola/IBM PowerPC 750 or 750
510 At the moment, this command just tells GDB what to name the
511 special-purpose processor registers. Since almost all the affected
512 registers are inaccessible to user-level programs, this command is
513 only useful for remote debugging in its present form.
517 Thanks to a major code donation from Hewlett-Packard, GDB now has much
518 more extensive support for HP-UX. Added features include shared
519 library support, kernel threads and hardware watchpoints for 11.00,
520 support for HP's ANSI C and C++ compilers, and a compatibility mode
521 for xdb and dbx commands.
525 HP's donation includes the new concept of catchpoints, which is a
526 generalization of the old catch command. On HP-UX, it is now possible
527 to catch exec, fork, and vfork, as well as library loading.
529 This means that the existing catch command has changed; its first
530 argument now specifies the type of catch to be set up. See the
531 output of "help catch" for a list of catchpoint types.
533 * Debugging across forks
535 On HP-UX, you can choose which process to debug when a fork() happens
540 HP has donated a curses-based terminal user interface (TUI). To get
541 it, build with --enable-tui. Although this can be enabled for any
542 configuration, at present it only works for native HP debugging.
544 * GDB remote protocol additions
546 A new protocol packet 'X' that writes binary data is now available.
547 Default behavior is to try 'X', then drop back to 'M' if the stub
548 fails to respond. The settable variable `remotebinarydownload'
549 allows explicit control over the use of 'X'.
551 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
552 full 64-bit address. The command
554 set remoteaddresssize 32
556 can be used to revert to the old behaviour. For existing remote stubs
557 the change should not be noticed, as the additional address information
560 In order to assist in debugging stubs, you may use the maintenance
561 command `packet' to send any text string to the stub. For instance,
563 maint packet heythere
565 sends the packet "$heythere#<checksum>". Note that it is very easy to
566 disrupt a debugging session by sending the wrong packet at the wrong
569 The compare-sections command allows you to compare section data on the
570 target to what is in the executable file without uploading or
571 downloading, by comparing CRC checksums.
573 * Tracing can collect general expressions
575 You may now collect general expressions at tracepoints. This requires
576 further additions to the target-side stub; see tracepoint.c and
577 doc/agentexpr.texi for further details.
579 * mask-address variable for Mips
581 For Mips targets, you may control the zeroing of the upper 32 bits of
582 a 64-bit address by entering `set mask-address on'. This is mainly
583 of interest to users of embedded R4xxx and R5xxx processors.
585 * Higher serial baud rates
587 GDB's serial code now allows you to specify baud rates 57600, 115200,
588 230400, and 460800 baud. (Note that your host system may not be able
589 to achieve all of these rates.)
593 The i960 configuration now includes an initial implementation of a
594 builtin simulator, contributed by Jim Wilson.
597 *** Changes in GDB-4.17:
599 * New native configurations
601 Alpha GNU/Linux alpha*-*-linux*
602 Unixware 2.x i[3456]86-unixware2*
603 Irix 6.x mips*-sgi-irix6*
604 PowerPC GNU/Linux powerpc-*-linux*
605 PowerPC Solaris powerpcle-*-solaris*
606 Sparc GNU/Linux sparc-*-linux*
607 Motorola sysV68 R3V7.1 m68k-motorola-sysv
611 Argonaut Risc Chip (ARC) arc-*-*
612 Hitachi H8/300S h8300*-*-*
613 Matsushita MN10200 w/simulator mn10200-*-*
614 Matsushita MN10300 w/simulator mn10300-*-*
615 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
616 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
617 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
618 Mitsubishi D10V w/simulator d10v-*-*
619 Mitsubishi M32R/D w/simulator m32r-*-elf*
620 Tsqware Sparclet sparclet-*-*
621 NEC V850 w/simulator v850-*-*
623 * New debugging protocols
625 ARM with RDI protocol arm*-*-*
626 M68K with dBUG monitor m68*-*-{aout,coff,elf}
627 DDB and LSI variants of PMON protocol mips*-*-*
628 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
629 PowerPC with SDS protocol powerpc{,le}-*-eabi
630 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
634 All configurations can now understand and use the DWARF 2 debugging
635 format. The choice is automatic, if the symbol file contains DWARF 2
640 GDB now includes basic Java language support. This support is
641 only useful with Java compilers that produce native machine code.
643 * solib-absolute-prefix and solib-search-path
645 For SunOS and SVR4 shared libraries, you may now set the prefix for
646 loading absolute shared library symbol files, and the search path for
647 locating non-absolute shared library symbol files.
649 * Live range splitting
651 GDB can now effectively debug code for which GCC has performed live
652 range splitting as part of its optimization. See gdb/doc/LRS for
653 more details on the expected format of the stabs information.
657 GDB's support for the GNU Hurd, including thread debugging, has been
658 updated to work with current versions of the Hurd.
662 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
663 instruction set. ARM GDB automatically detects when Thumb
664 instructions are in use, and adjusts disassembly and backtracing
669 GDB's MIPS target configurations now handle the MIP16 16-bit
674 GDB now includes support for overlays; if an executable has been
675 linked such that multiple sections are based at the same address, GDB
676 will decide which section to use for symbolic info. You can choose to
677 control the decision manually, using overlay commands, or implement
678 additional target-side support and use "overlay load-target" to bring
679 in the overlay mapping. Do "help overlay" for more detail.
683 The command "info symbol <address>" displays information about
684 the symbol at the specified address.
688 The standard remote protocol now includes an extension that allows
689 asynchronous collection and display of trace data. This requires
690 extensive support in the target-side debugging stub. Tracing mode
691 includes a new interaction mode in GDB and new commands: see the
692 file tracepoint.c for more details.
696 Configurations for embedded MIPS now include a simulator contributed
697 by Cygnus Solutions. The simulator supports the instruction sets
698 of most MIPS variants.
702 Sparc configurations may now include the ERC32 simulator contributed
703 by the European Space Agency. The simulator is not built into
704 Sparc targets by default; configure with --enable-sim to include it.
708 For target configurations that may include multiple variants of a
709 basic architecture (such as MIPS and SH), you may now set the
710 architecture explicitly. "set arch" sets, "info arch" lists
711 the possible architectures.
713 *** Changes in GDB-4.16:
715 * New native configurations
717 Windows 95, x86 Windows NT i[345]86-*-cygwin32
718 M68K NetBSD m68k-*-netbsd*
719 PowerPC AIX 4.x powerpc-*-aix*
720 PowerPC MacOS powerpc-*-macos*
721 PowerPC Windows NT powerpcle-*-cygwin32
722 RS/6000 AIX 4.x rs6000-*-aix4*
726 ARM with RDP protocol arm-*-*
727 I960 with MON960 i960-*-coff
728 MIPS VxWorks mips*-*-vxworks*
729 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
730 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
732 Matra Sparclet sparclet-*-*
736 The powerpc-eabi configuration now includes the PSIM simulator,
737 contributed by Andrew Cagney, with assistance from Mike Meissner.
738 PSIM is a very elaborate model of the PowerPC, including not only
739 basic instruction set execution, but also details of execution unit
740 performance and I/O hardware. See sim/ppc/README for more details.
744 GDB now works with Solaris 2.5.
746 * Windows 95/NT native
748 GDB will now work as a native debugger on Windows 95 and Windows NT.
749 To build it from source, you must use the "gnu-win32" environment,
750 which uses a DLL to emulate enough of Unix to run the GNU tools.
751 Further information, binaries, and sources are available at
752 ftp.cygnus.com, under pub/gnu-win32.
754 * dont-repeat command
756 If a user-defined command includes the command `dont-repeat', then the
757 command will not be repeated if the user just types return. This is
758 useful if the command is time-consuming to run, so that accidental
759 extra keystrokes don't run the same command many times.
761 * Send break instead of ^C
763 The standard remote protocol now includes an option to send a break
764 rather than a ^C to the target in order to interrupt it. By default,
765 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
767 * Remote protocol timeout
769 The standard remote protocol includes a new variable `remotetimeout'
770 that allows you to set the number of seconds before GDB gives up trying
771 to read from the target. The default value is 2.
773 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
775 By default GDB will automatically keep track of objects as they are
776 loaded and unloaded by the dynamic linker. By using the command `set
777 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
778 when shared library events occur, thus allowing you to set breakpoints
779 in shared libraries which are explicitly loaded by the inferior.
781 Note this feature does not work on hpux8. On hpux9 you must link
782 /usr/lib/end.o into your program. This feature should work
783 automatically on hpux10.
785 * Irix 5.x hardware watchpoint support
787 Irix 5 configurations now support the use of hardware watchpoints.
789 * Mips protocol "SYN garbage limit"
791 When debugging a Mips target using the `target mips' protocol, you
792 may set the number of characters that GDB will ignore by setting
793 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
794 every character. The default value is 1050.
796 * Recording and replaying remote debug sessions
798 If you set `remotelogfile' to the name of a file, gdb will write to it
799 a recording of a remote debug session. This recording may then be
800 replayed back to gdb using "gdbreplay". See gdbserver/README for
801 details. This is useful when you have a problem with GDB while doing
802 remote debugging; you can make a recording of the session and send it
803 to someone else, who can then recreate the problem.
805 * Speedups for remote debugging
807 GDB includes speedups for downloading and stepping MIPS systems using
808 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
809 and more efficient S-record downloading.
811 * Memory use reductions and statistics collection
813 GDB now uses less memory and reports statistics about memory usage.
814 Try the `maint print statistics' command, for example.
816 *** Changes in GDB-4.15:
820 The symbol reader for AIX GDB now uses partial symbol tables. This
821 can greatly improve startup time, especially for large executables.
823 * Remote targets use caching
825 Remote targets now use a data cache to speed up communication with the
826 remote side. The data cache could lead to incorrect results because
827 it doesn't know about volatile variables, thus making it impossible to
828 debug targets which use memory mapped I/O devices. `set remotecache
829 off' turns the the data cache off.
831 * Remote targets may have threads
833 The standard remote protocol now includes support for multiple threads
834 in the target system, using new protocol commands 'H' and 'T'. See
835 gdb/remote.c for details.
839 If GDB is configured with `--enable-netrom', then it will include
840 support for the NetROM ROM emulator from XLNT Designs. The NetROM
841 acts as though it is a bank of ROM on the target board, but you can
842 write into it over the network. GDB's support consists only of
843 support for fast loading into the emulated ROM; to debug, you must use
844 another protocol, such as standard remote protocol. The usual
845 sequence is something like
847 target nrom <netrom-hostname>
849 target remote <netrom-hostname>:1235
853 GDB now includes support for the Apple Macintosh, as a host only. It
854 may be run as either an MPW tool or as a standalone application, and
855 it can debug through the serial port. All the usual GDB commands are
856 available, but to the target command, you must supply "serial" as the
857 device type instead of "/dev/ttyXX". See mpw-README in the main
858 directory for more information on how to build. The MPW configuration
859 scripts */mpw-config.in support only a few targets, and only the
860 mips-idt-ecoff target has been tested.
864 GDB configuration now uses autoconf. This is not user-visible,
865 but does simplify configuration and building.
869 GDB now supports hpux10.
871 *** Changes in GDB-4.14:
873 * New native configurations
875 x86 FreeBSD i[345]86-*-freebsd
876 x86 NetBSD i[345]86-*-netbsd
877 NS32k NetBSD ns32k-*-netbsd
878 Sparc NetBSD sparc-*-netbsd
882 A29K VxWorks a29k-*-vxworks
883 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
884 CPU32 EST-300 emulator m68*-*-est*
885 PowerPC ELF powerpc-*-elf
888 * Alpha OSF/1 support for procfs
890 GDB now supports procfs under OSF/1-2.x and higher, which makes it
891 possible to attach to running processes. As the mounting of the /proc
892 filesystem is optional on the Alpha, GDB automatically determines
893 the availability of /proc during startup. This can lead to problems
894 if /proc is unmounted after GDB has been started.
896 * Arguments to user-defined commands
898 User commands may accept up to 10 arguments separated by whitespace.
899 Arguments are accessed within the user command via $arg0..$arg9. A
902 print $arg0 + $arg1 + $arg2
904 To execute the command use:
907 Defines the command "adder" which prints the sum of its three arguments.
908 Note the arguments are text substitutions, so they may reference variables,
909 use complex expressions, or even perform inferior function calls.
911 * New `if' and `while' commands
913 This makes it possible to write more sophisticated user-defined
914 commands. Both commands take a single argument, which is the
915 expression to evaluate, and must be followed by the commands to
916 execute, one per line, if the expression is nonzero, the list being
917 terminated by the word `end'. The `if' command list may include an
918 `else' word, which causes the following commands to be executed only
919 if the expression is zero.
921 * Fortran source language mode
923 GDB now includes partial support for Fortran 77. It will recognize
924 Fortran programs and can evaluate a subset of Fortran expressions, but
925 variables and functions may not be handled correctly. GDB will work
926 with G77, but does not yet know much about symbols emitted by other
929 * Better HPUX support
931 Most debugging facilities now work on dynamic executables for HPPAs
932 running hpux9 or later. You can attach to running dynamically linked
933 processes, but by default the dynamic libraries will be read-only, so
934 for instance you won't be able to put breakpoints in them. To change
935 that behavior do the following before running the program:
941 This will cause the libraries to be mapped private and read-write.
942 To revert to the normal behavior, do this:
948 You cannot set breakpoints or examine data in the library until after
949 the library is loaded if the function/data symbols do not have
952 GDB can now also read debug symbols produced by the HP C compiler on
953 HPPAs (sorry, no C++, Fortran or 68k support).
955 * Target byte order now dynamically selectable
957 You can choose which byte order to use with a target system, via the
958 commands "set endian big" and "set endian little", and you can see the
959 current setting by using "show endian". You can also give the command
960 "set endian auto", in which case GDB will use the byte order
961 associated with the executable. Currently, only embedded MIPS
962 configurations support dynamic selection of target byte order.
964 * New DOS host serial code
966 This version uses DPMI interrupts to handle buffered I/O, so you
967 no longer need to run asynctsr when debugging boards connected to
970 *** Changes in GDB-4.13:
972 * New "complete" command
974 This lists all the possible completions for the rest of the line, if it
975 were to be given as a command itself. This is intended for use by emacs.
977 * Trailing space optional in prompt
979 "set prompt" no longer adds a space for you after the prompt you set. This
980 allows you to set a prompt which ends in a space or one that does not.
982 * Breakpoint hit counts
984 "info break" now displays a count of the number of times the breakpoint
985 has been hit. This is especially useful in conjunction with "ignore"; you
986 can ignore a large number of breakpoint hits, look at the breakpoint info
987 to see how many times the breakpoint was hit, then run again, ignoring one
988 less than that number, and this will get you quickly to the last hit of
991 * Ability to stop printing at NULL character
993 "set print null-stop" will cause GDB to stop printing the characters of
994 an array when the first NULL is encountered. This is useful when large
995 arrays actually contain only short strings.
997 * Shared library breakpoints
999 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
1000 breakpoints in shared libraries before the executable is run.
1002 * Hardware watchpoints
1004 There is a new hardware breakpoint for the watch command for sparclite
1005 targets. See gdb/sparclite/hw_breakpoint.note.
1007 Hardware watchpoints are also now supported under GNU/Linux.
1011 Annotations have been added. These are for use with graphical interfaces,
1012 and are still experimental. Currently only gdba.el uses these.
1014 * Improved Irix 5 support
1016 GDB now works properly with Irix 5.2.
1018 * Improved HPPA support
1020 GDB now works properly with the latest GCC and GAS.
1022 * New native configurations
1024 Sequent PTX4 i[34]86-sequent-ptx4
1025 HPPA running OSF/1 hppa*-*-osf*
1026 Atari TT running SVR4 m68*-*-sysv4*
1027 RS/6000 LynxOS rs6000-*-lynxos*
1031 OS/9000 i[34]86-*-os9k
1032 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
1035 * Hitachi SH7000 and E7000-PC ICE support
1037 There is now support for communicating with the Hitachi E7000-PC ICE.
1038 This is available automatically when GDB is configured for the SH.
1042 As usual, a variety of small fixes and improvements, both generic
1043 and configuration-specific. See the ChangeLog for more detail.
1045 *** Changes in GDB-4.12:
1047 * Irix 5 is now supported
1051 GDB-4.12 on the HPPA has a number of changes which make it unable
1052 to debug the output from the currently released versions of GCC and
1053 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
1054 of GCC and GAS, versions of these tools designed to work with GDB-4.12
1055 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
1058 *** Changes in GDB-4.11:
1060 * User visible changes:
1064 The "set remotedebug" option is now consistent between the mips remote
1065 target, remote targets using the gdb-specific protocol, UDI (AMD's
1066 debug protocol for the 29k) and the 88k bug monitor. It is now an
1067 integer specifying a debug level (normally 0 or 1, but 2 means more
1068 debugging info for the mips target).
1070 * DEC Alpha native support
1072 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
1073 debug info, but GDB works fairly well with the DEC compiler and should
1074 work with a future GCC release. See the README file for a few
1075 Alpha-specific notes.
1077 * Preliminary thread implementation
1079 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
1081 * LynxOS native and target support for 386
1083 This release has been hosted on LynxOS 2.2, and also can be configured
1084 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
1087 * Improvements in C++ mangling/demangling.
1089 This release has much better g++ debugging, specifically in name
1090 mangling/demangling, virtual function calls, print virtual table,
1091 call methods, ...etc.
1093 *** Changes in GDB-4.10:
1095 * User visible changes:
1097 Remote debugging using the GDB-specific (`target remote') protocol now
1098 supports the `load' command. This is only useful if you have some
1099 other way of getting the stub to the target system, and you can put it
1100 somewhere in memory where it won't get clobbered by the download.
1102 Filename completion now works.
1104 When run under emacs mode, the "info line" command now causes the
1105 arrow to point to the line specified. Also, "info line" prints
1106 addresses in symbolic form (as well as hex).
1108 All vxworks based targets now support a user settable option, called
1109 vxworks-timeout. This option represents the number of seconds gdb
1110 should wait for responses to rpc's. You might want to use this if
1111 your vxworks target is, perhaps, a slow software simulator or happens
1112 to be on the far side of a thin network line.
1116 This release contains support for using a DEC alpha as a GDB host for
1117 cross debugging. Native alpha debugging is not supported yet.
1120 *** Changes in GDB-4.9:
1124 This is the first GDB release which is accompanied by a matching testsuite.
1125 The testsuite requires installation of dejagnu, which should be available
1126 via ftp from most sites that carry GNU software.
1130 'Cfront' style demangling has had its name changed to 'ARM' style, to
1131 emphasize that it was written from the specifications in the C++ Annotated
1132 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
1133 disclaimers, it still generated too much confusion with users attempting to
1134 use gdb with AT&T cfront.
1138 GDB now uses a standard remote interface to a simulator library.
1139 So far, the library contains simulators for the Zilog Z8001/2, the
1140 Hitachi H8/300, H8/500 and Super-H.
1142 * New targets supported
1144 H8/300 simulator h8300-hitachi-hms or h8300hms
1145 H8/500 simulator h8500-hitachi-hms or h8500hms
1146 SH simulator sh-hitachi-hms or sh
1147 Z8000 simulator z8k-zilog-none or z8ksim
1148 IDT MIPS board over serial line mips-idt-ecoff
1150 Cross-debugging to GO32 targets is supported. It requires a custom
1151 version of the i386-stub.c module which is integrated with the
1152 GO32 memory extender.
1154 * New remote protocols
1156 MIPS remote debugging protocol.
1158 * New source languages supported
1160 This version includes preliminary support for Chill, a Pascal like language
1161 used by telecommunications companies. Chill support is also being integrated
1162 into the GNU compiler, but we don't know when it will be publically available.
1165 *** Changes in GDB-4.8:
1167 * HP Precision Architecture supported
1169 GDB now supports HP PA-RISC machines running HPUX. A preliminary
1170 version of this support was available as a set of patches from the
1171 University of Utah. GDB does not support debugging of programs
1172 compiled with the HP compiler, because HP will not document their file
1173 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
1174 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
1176 Many problems in the preliminary version have been fixed.
1178 * Faster and better demangling
1180 We have improved template demangling and fixed numerous bugs in the GNU style
1181 demangler. It can now handle type modifiers such as `static' or `const'. Wide
1182 character types (wchar_t) are now supported. Demangling of each symbol is now
1183 only done once, and is cached when the symbol table for a file is read in.
1184 This results in a small increase in memory usage for C programs, a moderate
1185 increase in memory usage for C++ programs, and a fantastic speedup in
1188 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
1189 from the specifications in the Annotated Reference Manual, which AT&T's
1190 compiler does not actually implement.
1192 * G++ multiple inheritance compiler problem
1194 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
1195 inheritance lattices was reworked to properly discover ambiguities. We
1196 recently found an example which causes this new algorithm to fail in a
1197 very subtle way, producing bad debug information for those classes.
1198 The file 'gcc.patch' (in this directory) can be applied to gcc to
1199 circumvent the problem. A future GCC release will contain a complete
1202 The previous G++ debug info problem (mentioned below for the gdb-4.7
1203 release) is fixed in gcc version 2.3.2.
1205 * Improved configure script
1207 The `configure' script will now attempt to guess your system type if
1208 you don't supply a host system type. The old scheme of supplying a
1209 host system triplet is preferable over using this. All the magic is
1210 done in the new `config.guess' script. Examine it for details.
1212 We have also brought our configure script much more in line with the FSF's
1213 version. It now supports the --with-xxx options. In particular,
1214 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
1215 The resulting GDB will not be able to read arbitrary object file formats --
1216 only the format ``expected'' to be used on the configured target system.
1217 We hope to make this the default in a future release.
1219 * Documentation improvements
1221 There's new internal documentation on how to modify GDB, and how to
1222 produce clean changes to the code. We implore people to read it
1223 before submitting changes.
1225 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
1226 M4 macros. The new texinfo.tex is provided in this release. Pre-built
1227 `info' files are also provided. To build `info' files from scratch,
1228 you will need the latest `makeinfo' release, which will be available in
1229 a future texinfo-X.Y release.
1231 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
1232 We're not sure exactly which versions have this problem, but it has
1233 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
1234 or better. If that isn't possible, there is a patch in
1235 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
1236 around this problem.
1240 GDB now supports array constants that can be used in expressions typed in by
1241 the user. The syntax is `{element, element, ...}'. Ie: you can now type
1242 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
1245 The new directory `gdb/sparclite' contains a program that demonstrates
1246 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
1248 * New native hosts supported
1250 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
1251 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
1253 * New targets supported
1255 AMD 29k family via UDI a29k-amd-udi or udi29k
1257 * New file formats supported
1259 BFD now supports reading HP/PA-RISC executables (SOM file format?),
1260 HPUX core files, and SCO 3.2v2 core files.
1264 Attaching to processes now works again; thanks for the many bug reports.
1266 We have also stomped on a bunch of core dumps caused by
1267 printf_filtered("%s") problems.
1269 We eliminated a copyright problem on the rpc and ptrace header files
1270 for VxWorks, which was discovered at the last minute during the 4.7
1271 release. You should now be able to build a VxWorks GDB.
1273 You can now interrupt gdb while an attached process is running. This
1274 will cause the attached process to stop, and give control back to GDB.
1276 We fixed problems caused by using too many file descriptors
1277 for reading symbols from object files and libraries. This was
1278 especially a problem for programs that used many (~100) shared
1281 The `step' command now only enters a subroutine if there is line number
1282 information for the subroutine. Otherwise it acts like the `next'
1283 command. Previously, `step' would enter subroutines if there was
1284 any debugging information about the routine. This avoids problems
1285 when using `cc -g1' on MIPS machines.
1287 * Internal improvements
1289 GDB's internal interfaces have been improved to make it easier to support
1290 debugging of multiple languages in the future.
1292 GDB now uses a common structure for symbol information internally.
1293 Minimal symbols (derived from linkage symbols in object files), partial
1294 symbols (from a quick scan of debug information), and full symbols
1295 contain a common subset of information, making it easier to write
1296 shared code that handles any of them.
1298 * New command line options
1300 We now accept --silent as an alias for --quiet.
1304 The memory-mapped-malloc library is now licensed under the GNU Library
1305 General Public License.
1307 *** Changes in GDB-4.7:
1309 * Host/native/target split
1311 GDB has had some major internal surgery to untangle the support for
1312 hosts and remote targets. Now, when you configure GDB for a remote
1313 target, it will no longer load in all of the support for debugging
1314 local programs on the host. When fully completed and tested, this will
1315 ensure that arbitrary host/target combinations are possible.
1317 The primary conceptual shift is to separate the non-portable code in
1318 GDB into three categories. Host specific code is required any time GDB
1319 is compiled on that host, regardless of the target. Target specific
1320 code relates to the peculiarities of the target, but can be compiled on
1321 any host. Native specific code is everything else: it can only be
1322 built when the host and target are the same system. Child process
1323 handling and core file support are two common `native' examples.
1325 GDB's use of /proc for controlling Unix child processes is now cleaner.
1326 It has been split out into a single module under the `target_ops' vector,
1327 plus two native-dependent functions for each system that uses /proc.
1329 * New hosts supported
1331 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
1332 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1333 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
1335 * New targets supported
1337 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1338 68030 and CPU32 m68030-*-*, m68332-*-*
1340 * New native hosts supported
1342 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1343 (386bsd is not well tested yet)
1344 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
1346 * New file formats supported
1348 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
1349 supports reading of `a.out.adobe' object files, which are an a.out
1350 format extended with minimal information about multiple sections.
1354 `show copying' is the same as the old `info copying'.
1355 `show warranty' is the same as `info warrantee'.
1356 These were renamed for consistency. The old commands continue to work.
1358 `info handle' is a new alias for `info signals'.
1360 You can now define pre-command hooks, which attach arbitrary command
1361 scripts to any command. The commands in the hook will be executed
1362 prior to the user's command. You can also create a hook which will be
1363 executed whenever the program stops. See gdb.texinfo.
1367 We now deal with Cfront style name mangling, and can even extract type
1368 info from mangled symbols. GDB can automatically figure out which
1369 symbol mangling style your C++ compiler uses.
1371 Calling of methods and virtual functions has been improved as well.
1375 The crash that occured when debugging Sun Ansi-C compiled binaries is
1376 fixed. This was due to mishandling of the extra N_SO stabs output
1379 We also finally got Ultrix 4.2 running in house, and fixed core file
1380 support, with help from a dozen people on the net.
1382 John M. Farrell discovered that the reason that single-stepping was so
1383 slow on all of the Mips based platforms (primarily SGI and DEC) was
1384 that we were trying to demangle and lookup a symbol used for internal
1385 purposes on every instruction that was being stepped through. Changing
1386 the name of that symbol so that it couldn't be mistaken for a C++
1387 mangled symbol sped things up a great deal.
1389 Rich Pixley sped up symbol lookups in general by getting much smarter
1390 about when C++ symbol mangling is necessary. This should make symbol
1391 completion (TAB on the command line) much faster. It's not as fast as
1392 we'd like, but it's significantly faster than gdb-4.6.
1396 A new user controllable variable 'call_scratch_address' can
1397 specify the location of a scratch area to be used when GDB
1398 calls a function in the target. This is necessary because the
1399 usual method of putting the scratch area on the stack does not work
1400 in systems that have separate instruction and data spaces.
1402 We integrated changes to support the 29k UDI (Universal Debugger
1403 Interface), but discovered at the last minute that we didn't have all
1404 of the appropriate copyright paperwork. We are working with AMD to
1405 resolve this, and hope to have it available soon.
1409 We have sped up the remote serial line protocol, especially for targets
1410 with lots of registers. It now supports a new `expedited status' ('T')
1411 message which can be used in place of the existing 'S' status message.
1412 This allows the remote stub to send only the registers that GDB
1413 needs to make a quick decision about single-stepping or conditional
1414 breakpoints, eliminating the need to fetch the entire register set for
1415 each instruction being stepped through.
1417 The GDB remote serial protocol now implements a write-through cache for
1418 registers, only re-reading the registers if the target has run.
1420 There is also a new remote serial stub for SPARC processors. You can
1421 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
1422 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
1423 processor with a serial port.
1427 Configure.in files have become much easier to read and modify. A new
1428 `table driven' format makes it more obvious what configurations are
1429 supported, and what files each one uses.
1433 There is a new opcodes library which will eventually contain all of the
1434 disassembly routines and opcode tables. At present, it only contains
1435 Sparc and Z8000 routines. This will allow the assembler, debugger, and
1436 disassembler (binutils/objdump) to share these routines.
1438 The libiberty library is now copylefted under the GNU Library General
1439 Public License. This allows more liberal use, and was done so libg++
1440 can use it. This makes no difference to GDB, since the Library License
1441 grants all the rights from the General Public License.
1445 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
1446 reference to the stabs symbol info used by the debugger. It is (as far
1447 as we know) the only published document on this fascinating topic. We
1448 encourage you to read it, compare it to the stabs information on your
1449 system, and send improvements on the document in general (to
1450 bug-gdb@prep.ai.mit.edu).
1452 And, of course, many bugs have been fixed.
1455 *** Changes in GDB-4.6:
1457 * Better support for C++ function names
1459 GDB now accepts as input the "demangled form" of C++ overloaded function
1460 names and member function names, and can do command completion on such names
1461 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
1462 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
1463 Make use of command completion, it is your friend.
1465 GDB also now accepts a variety of C++ mangled symbol formats. They are
1466 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
1467 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
1468 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
1469 for the list of formats.
1471 * G++ symbol mangling problem
1473 Recent versions of gcc have a bug in how they emit debugging information for
1474 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
1475 directory) can be applied to gcc to fix the problem. Alternatively, if you
1476 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
1477 usual symptom is difficulty with setting breakpoints on methods. GDB complains
1478 about the method being non-existent. (We believe that version 2.2.2 of GCC has
1481 * New 'maintenance' command
1483 All of the commands related to hacking GDB internals have been moved out of
1484 the main command set, and now live behind the 'maintenance' command. This
1485 can also be abbreviated as 'mt'. The following changes were made:
1487 dump-me -> maintenance dump-me
1488 info all-breakpoints -> maintenance info breakpoints
1489 printmsyms -> maintenance print msyms
1490 printobjfiles -> maintenance print objfiles
1491 printpsyms -> maintenance print psymbols
1492 printsyms -> maintenance print symbols
1494 The following commands are new:
1496 maintenance demangle Call internal GDB demangler routine to
1497 demangle a C++ link name and prints the result.
1498 maintenance print type Print a type chain for a given symbol
1500 * Change to .gdbinit file processing
1502 We now read the $HOME/.gdbinit file before processing the argv arguments
1503 (e.g. reading symbol files or core files). This allows global parameters to
1504 be set, which will apply during the symbol reading. The ./.gdbinit is still
1505 read after argv processing.
1507 * New hosts supported
1509 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
1511 GNU/Linux support i386-unknown-linux or linux
1513 We are also including code to support the HP/PA running BSD and HPUX. This
1514 is almost guaranteed not to work, as we didn't have time to test or build it
1515 for this release. We are including it so that the more adventurous (or
1516 masochistic) of you can play with it. We also had major problems with the
1517 fact that the compiler that we got from HP doesn't support the -g option.
1520 * New targets supported
1522 Hitachi H8/300 h8300-hitachi-hms or h8300hms
1524 * More smarts about finding #include files
1526 GDB now remembers the compilation directory for all include files, and for
1527 all files from which C is generated (like yacc and lex sources). This
1528 greatly improves GDB's ability to find yacc/lex sources, and include files,
1529 especially if you are debugging your program from a directory different from
1530 the one that contains your sources.
1532 We also fixed a bug which caused difficulty with listing and setting
1533 breakpoints in include files which contain C code. (In the past, you had to
1534 try twice in order to list an include file that you hadn't looked at before.)
1536 * Interesting infernals change
1538 GDB now deals with arbitrary numbers of sections, where the symbols for each
1539 section must be relocated relative to that section's landing place in the
1540 target's address space. This work was needed to support ELF with embedded
1541 stabs used by Solaris-2.0.
1543 * Bug fixes (of course!)
1545 There have been loads of fixes for the following things:
1546 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
1547 i960, stabs, DOS(GO32), procfs, etc...
1549 See the ChangeLog for details.
1551 *** Changes in GDB-4.5:
1553 * New machines supported (host and target)
1555 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
1557 SGI Irix-4.x mips-sgi-irix4 or iris4
1559 * New malloc package
1561 GDB now uses a new memory manager called mmalloc, based on gmalloc.
1562 Mmalloc is capable of handling mutiple heaps of memory. It is also
1563 capable of saving a heap to a file, and then mapping it back in later.
1564 This can be used to greatly speedup the startup of GDB by using a
1565 pre-parsed symbol table which lives in a mmalloc managed heap. For
1566 more details, please read mmalloc/mmalloc.texi.
1570 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
1571 'help info proc' for details.
1573 * MIPS ecoff symbol table format
1575 The code that reads MIPS symbol table format is now supported on all hosts.
1576 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
1579 * File name changes for MS-DOS
1581 Many files in the config directories have been renamed to make it easier to
1582 support GDB on MS-DOSe systems (which have very restrictive file name
1583 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
1584 environment) is close to working but has some remaining problems. Note
1585 that debugging of DOS programs is not supported, due to limitations
1586 in the ``operating system'', but it can be used to host cross-debugging.
1588 * Cross byte order fixes
1590 Many fixes have been made to support cross debugging of Sparc and MIPS
1591 targets from hosts whose byte order differs.
1593 * New -mapped and -readnow options
1595 If memory-mapped files are available on your system through the 'mmap'
1596 system call, you can use the -mapped option on the `file' or
1597 `symbol-file' commands to cause GDB to write the symbols from your
1598 program into a reusable file. If the program you are debugging is
1599 called `/path/fred', the mapped symbol file will be `./fred.syms'.
1600 Future GDB debugging sessions will notice the presence of this file,
1601 and will quickly map in symbol information from it, rather than reading
1602 the symbol table from the executable program. Using the '-mapped'
1603 option in a GDB `file' or `symbol-file' command has the same effect as
1604 starting GDB with the '-mapped' command-line option.
1606 You can cause GDB to read the entire symbol table immediately by using
1607 the '-readnow' option with any of the commands that load symbol table
1608 information (or on the GDB command line). This makes the command
1609 slower, but makes future operations faster.
1611 The -mapped and -readnow options are typically combined in order to
1612 build a `fred.syms' file that contains complete symbol information.
1613 A simple GDB invocation to do nothing but build a `.syms' file for future
1616 gdb -batch -nx -mapped -readnow programname
1618 The `.syms' file is specific to the host machine on which GDB is run.
1619 It holds an exact image of GDB's internal symbol table. It cannot be
1620 shared across multiple host platforms.
1622 * longjmp() handling
1624 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
1625 siglongjmp() without losing control. This feature has not yet been ported to
1626 all systems. It currently works on many 386 platforms, all MIPS-based
1627 platforms (SGI, DECstation, etc), and Sun3/4.
1631 Preliminary work has been put in to support the new Solaris OS from Sun. At
1632 this time, it can control and debug processes, but it is not capable of
1637 As always, many many bug fixes. The major areas were with g++, and mipsread.
1638 People using the MIPS-based platforms should experience fewer mysterious
1639 crashes and trashed symbol tables.
1641 *** Changes in GDB-4.4:
1643 * New machines supported (host and target)
1645 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1647 BSD Reno on Vax vax-dec-bsd
1648 Ultrix on Vax vax-dec-ultrix
1650 * New machines supported (target)
1652 AMD 29000 embedded, using EBMON a29k-none-none
1656 GDB continues to improve its handling of C++. `References' work better.
1657 The demangler has also been improved, and now deals with symbols mangled as
1658 per the Annotated C++ Reference Guide.
1660 GDB also now handles `stabs' symbol information embedded in MIPS
1661 `ecoff' symbol tables. Since the ecoff format was not easily
1662 extensible to handle new languages such as C++, this appeared to be a
1663 good way to put C++ debugging info into MIPS binaries. This option
1664 will be supported in the GNU C compiler, version 2, when it is
1667 * New features for SVR4
1669 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
1670 shared libraries. Debugging dynamically linked programs should present
1671 only minor differences from debugging statically linked programs.
1673 The `info proc' command will print out information about any process
1674 on an SVR4 system (including the one you are debugging). At the moment,
1675 it prints the address mappings of the process.
1677 If you bring up GDB on another SVR4 system, please send mail to
1678 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
1680 * Better dynamic linking support in SunOS
1682 Reading symbols from shared libraries which contain debugging symbols
1683 now works properly. However, there remain issues such as automatic
1684 skipping of `transfer vector' code during function calls, which
1685 make it harder to debug code in a shared library, than to debug the
1686 same code linked statically.
1690 GDB is now using the latest `getopt' routines from the FSF. This
1691 version accepts the -- prefix for options with long names. GDB will
1692 continue to accept the old forms (-option and +option) as well.
1693 Various single letter abbreviations for options have been explicity
1694 added to the option table so that they won't get overshadowed in the
1695 future by other options that begin with the same letter.
1699 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
1700 Many assorted bugs have been handled. Many more remain to be handled.
1701 See the various ChangeLog files (primarily in gdb and bfd) for details.
1704 *** Changes in GDB-4.3:
1706 * New machines supported (host and target)
1708 Amiga 3000 running Amix m68k-cbm-svr4 or amix
1709 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
1710 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1712 * Almost SCO Unix support
1714 We had hoped to support:
1715 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1716 (except for core file support), but we discovered very late in the release
1717 that it has problems with process groups that render gdb unusable. Sorry
1718 about that. I encourage people to fix it and post the fixes.
1720 * Preliminary ELF and DWARF support
1722 GDB can read ELF object files on System V Release 4, and can handle
1723 debugging records for C, in DWARF format, in ELF files. This support
1724 is preliminary. If you bring up GDB on another SVR4 system, please
1725 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
1730 GDB now uses the latest `readline' library. One user-visible change
1731 is that two tabs will list possible command completions, which previously
1732 required typing M-? (meta-question mark, or ESC ?).
1736 The `stepi' bug that many of you noticed has been squashed.
1737 Many bugs in C++ have been handled. Many more remain to be handled.
1738 See the various ChangeLog files (primarily in gdb and bfd) for details.
1740 * State of the MIPS world (in case you wondered):
1742 GDB can understand the symbol tables emitted by the compilers
1743 supplied by most vendors of MIPS-based machines, including DEC. These
1744 symbol tables are in a format that essentially nobody else uses.
1746 Some versions of gcc come with an assembler post-processor called
1747 mips-tfile. This program is required if you want to do source-level
1748 debugging of gcc-compiled programs. I believe FSF does not ship
1749 mips-tfile with gcc version 1, but it will eventually come with gcc
1752 Debugging of g++ output remains a problem. g++ version 1.xx does not
1753 really support it at all. (If you're lucky, you should be able to get
1754 line numbers and stack traces to work, but no parameters or local
1755 variables.) With some work it should be possible to improve the
1758 When gcc version 2 is released, you will have somewhat better luck.
1759 However, even then you will get confusing results for inheritance and
1762 We will eventually provide full debugging of g++ output on
1763 DECstations. This will probably involve some kind of stabs-in-ecoff
1764 encapulation, but the details have not been worked out yet.
1767 *** Changes in GDB-4.2:
1769 * Improved configuration
1771 Only one copy of `configure' exists now, and it is not self-modifying.
1772 Porting BFD is simpler.
1776 The `step' and `next' commands now only stop at the first instruction
1777 of a source line. This prevents the multiple stops that used to occur
1778 in switch statements, for-loops, etc. `Step' continues to stop if a
1779 function that has debugging information is called within the line.
1783 Lots of small bugs fixed. More remain.
1785 * New host supported (not target)
1787 Intel 386 PC clone running Mach i386-none-mach
1790 *** Changes in GDB-4.1:
1792 * Multiple source language support
1794 GDB now has internal scaffolding to handle several source languages.
1795 It determines the type of each source file from its filename extension,
1796 and will switch expression parsing and number formatting to match the
1797 language of the function in the currently selected stack frame.
1798 You can also specifically set the language to be used, with
1799 `set language c' or `set language modula-2'.
1803 GDB now has preliminary support for the GNU Modula-2 compiler,
1804 currently under development at the State University of New York at
1805 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
1806 continue through the fall of 1991 and into 1992.
1808 Other Modula-2 compilers are currently not supported, and attempting to
1809 debug programs compiled with them will likely result in an error as the
1810 symbol table is read. Feel free to work on it, though!
1812 There are hooks in GDB for strict type checking and range checking,
1813 in the `Modula-2 philosophy', but they do not currently work.
1817 GDB can now write to executable and core files (e.g. patch
1818 a variable's value). You must turn this switch on, specify
1819 the file ("exec foo" or "core foo"), *then* modify it, e.g.
1820 by assigning a new value to a variable. Modifications take
1823 * Automatic SunOS shared library reading
1825 When you run your program, GDB automatically determines where its
1826 shared libraries (if any) have been loaded, and reads their symbols.
1827 The `share' command is no longer needed. This also works when
1828 examining core files.
1832 You can specify the number of lines that the `list' command shows.
1835 * New machines supported (host and target)
1837 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1838 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
1839 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
1841 * New hosts supported (not targets)
1843 IBM RT/PC: romp-ibm-aix or rtpc
1845 * New targets supported (not hosts)
1847 AMD 29000 embedded with COFF a29k-none-coff
1848 AMD 29000 embedded with a.out a29k-none-aout
1849 Ultracomputer remote kernel debug a29k-nyu-kern
1851 * New remote interfaces
1857 *** Changes in GDB-4.0:
1861 Wide output is wrapped at good places to make the output more readable.
1863 Gdb now supports cross-debugging from a host machine of one type to a
1864 target machine of another type. Communication with the target system
1865 is over serial lines. The ``target'' command handles connecting to the
1866 remote system; the ``load'' command will download a program into the
1867 remote system. Serial stubs for the m68k and i386 are provided. Gdb
1868 also supports debugging of realtime processes running under VxWorks,
1869 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
1870 stub on the target system.
1872 New CPUs supported include the AMD 29000 and Intel 960.
1874 GDB now reads object files and symbol tables via a ``binary file''
1875 library, which allows a single copy of GDB to debug programs of multiple
1876 object file types such as a.out and coff.
1878 There is now a GDB reference card in "doc/refcard.tex". (Make targets
1879 refcard.dvi and refcard.ps are available to format it).
1882 * Control-Variable user interface simplified
1884 All variables that control the operation of the debugger can be set
1885 by the ``set'' command, and displayed by the ``show'' command.
1887 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
1888 ``Show prompt'' produces the response:
1889 Gdb's prompt is new-gdb=>.
1891 What follows are the NEW set commands. The command ``help set'' will
1892 print a complete list of old and new set commands. ``help set FOO''
1893 will give a longer description of the variable FOO. ``show'' will show
1894 all of the variable descriptions and their current settings.
1896 confirm on/off: Enables warning questions for operations that are
1897 hard to recover from, e.g. rerunning the program while
1898 it is already running. Default is ON.
1900 editing on/off: Enables EMACS style command line editing
1901 of input. Previous lines can be recalled with
1902 control-P, the current line can be edited with control-B,
1903 you can search for commands with control-R, etc.
1906 history filename NAME: NAME is where the gdb command history
1907 will be stored. The default is .gdb_history,
1908 or the value of the environment variable
1911 history size N: The size, in commands, of the command history. The
1912 default is 256, or the value of the environment variable
1915 history save on/off: If this value is set to ON, the history file will
1916 be saved after exiting gdb. If set to OFF, the
1917 file will not be saved. The default is OFF.
1919 history expansion on/off: If this value is set to ON, then csh-like
1920 history expansion will be performed on
1921 command line input. The default is OFF.
1923 radix N: Sets the default radix for input and output. It can be set
1924 to 8, 10, or 16. Note that the argument to "radix" is interpreted
1925 in the current radix, so "set radix 10" is always a no-op.
1927 height N: This integer value is the number of lines on a page. Default
1928 is 24, the current `stty rows'' setting, or the ``li#''
1929 setting from the termcap entry matching the environment
1932 width N: This integer value is the number of characters on a line.
1933 Default is 80, the current `stty cols'' setting, or the ``co#''
1934 setting from the termcap entry matching the environment
1937 Note: ``set screensize'' is obsolete. Use ``set height'' and
1938 ``set width'' instead.
1940 print address on/off: Print memory addresses in various command displays,
1941 such as stack traces and structure values. Gdb looks
1942 more ``symbolic'' if you turn this off; it looks more
1943 ``machine level'' with it on. Default is ON.
1945 print array on/off: Prettyprint arrays. New convenient format! Default
1948 print demangle on/off: Print C++ symbols in "source" form if on,
1951 print asm-demangle on/off: Same, for assembler level printouts
1954 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
1957 * Support for Epoch Environment.
1959 The epoch environment is a version of Emacs v18 with windowing. One
1960 new command, ``inspect'', is identical to ``print'', except that if you
1961 are running in the epoch environment, the value is printed in its own
1965 * Support for Shared Libraries
1967 GDB can now debug programs and core files that use SunOS shared libraries.
1968 Symbols from a shared library cannot be referenced
1969 before the shared library has been linked with the program (this
1970 happens after you type ``run'' and before the function main() is entered).
1971 At any time after this linking (including when examining core files
1972 from dynamically linked programs), gdb reads the symbols from each
1973 shared library when you type the ``sharedlibrary'' command.
1974 It can be abbreviated ``share''.
1976 sharedlibrary REGEXP: Load shared object library symbols for files
1977 matching a unix regular expression. No argument
1978 indicates to load symbols for all shared libraries.
1980 info sharedlibrary: Status of loaded shared libraries.
1985 A watchpoint stops execution of a program whenever the value of an
1986 expression changes. Checking for this slows down execution
1987 tremendously whenever you are in the scope of the expression, but is
1988 quite useful for catching tough ``bit-spreader'' or pointer misuse
1989 problems. Some machines such as the 386 have hardware for doing this
1990 more quickly, and future versions of gdb will use this hardware.
1992 watch EXP: Set a watchpoint (breakpoint) for an expression.
1994 info watchpoints: Information about your watchpoints.
1996 delete N: Deletes watchpoint number N (same as breakpoints).
1997 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
1998 enable N: Re-enables watchpoint number N (same as breakpoints).
2001 * C++ multiple inheritance
2003 When used with a GCC version 2 compiler, GDB supports multiple inheritance
2006 * C++ exception handling
2008 Gdb now supports limited C++ exception handling. Besides the existing
2009 ability to breakpoint on an exception handler, gdb can breakpoint on
2010 the raising of an exception (before the stack is peeled back to the
2013 catch FOO: If there is a FOO exception handler in the dynamic scope,
2014 set a breakpoint to catch exceptions which may be raised there.
2015 Multiple exceptions (``catch foo bar baz'') may be caught.
2017 info catch: Lists all exceptions which may be caught in the
2018 current stack frame.
2021 * Minor command changes
2023 The command ``call func (arg, arg, ...)'' now acts like the print
2024 command, except it does not print or save a value if the function's result
2025 is void. This is similar to dbx usage.
2027 The ``up'' and ``down'' commands now always print the frame they end up
2028 at; ``up-silently'' and `down-silently'' can be used in scripts to change
2029 frames without printing.
2031 * New directory command
2033 'dir' now adds directories to the FRONT of the source search path.
2034 The path starts off empty. Source files that contain debug information
2035 about the directory in which they were compiled can be found even
2036 with an empty path; Sun CC and GCC include this information. If GDB can't
2037 find your source file in the current directory, type "dir .".
2039 * Configuring GDB for compilation
2041 For normal use, type ``./configure host''. See README or gdb.texinfo
2044 GDB now handles cross debugging. If you are remotely debugging between
2045 two different machines, type ``./configure host -target=targ''.
2046 Host is the machine where GDB will run; targ is the machine
2047 where the program that you are debugging will run.
projects / deliverable / binutils-gdb.git / blob