1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 5.2:
6 * Changes in Alpha configurations.
8 Multi-arch support is enabled for all Alpha configurations.
10 * New command "set max-user-call-depth <nnn>"
12 This command allows the user to limit the call depth of user-defined
13 commands. The default is 1024.
15 * Changes in FreeBSD/i386 native debugging.
17 Support for the "generate-core-file" has been added.
19 * New commands "dump", "append", and "restore".
21 These commands allow data to be copied from target memory
22 to a bfd-format or binary file (dump and append), and back
23 from a file into memory (restore).
25 *** Changes in GDB 5.2:
27 * New command "set trust-readonly-sections on[off]".
29 This command is a hint that tells gdb that read-only sections
30 really are read-only (ie. that their contents will not change).
31 In this mode, gdb will go to the object file rather than the
32 target to read memory from read-only sections (such as ".text").
33 This can be a significant performance improvement on some
34 (notably embedded) targets.
36 * New command "generate-core-file" (or "gcore").
38 This new gdb command allows the user to drop a core file of the child
39 process state at any time. So far it's been implemented only for
40 GNU/Linux and Solaris, but should be relatively easily ported to other
41 hosts. Argument is core file name (defaults to core.<pid>).
43 * New command line option
45 GDB now accepts --pid or -p followed by a process id.
47 * Change in command line behavior -- corefiles vs. process ids.
49 There is a subtle behavior in the way in which GDB handles
50 command line arguments. The first non-flag argument is always
51 a program to debug, but the second non-flag argument may either
52 be a corefile or a process id. Previously, GDB would attempt to
53 open the second argument as a corefile, and if that failed, would
54 issue a superfluous error message and then attempt to attach it as
55 a process. Now, if the second argument begins with a non-digit,
56 it will be treated as a corefile. If it begins with a digit,
57 GDB will attempt to attach it as a process, and if no such process
58 is found, will then attempt to open it as a corefile.
60 * Changes in ARM configurations.
62 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
63 configuration is fully multi-arch.
65 * New native configurations
67 ARM NetBSD arm*-*-netbsd*
68 x86 OpenBSD i[3456]86-*-openbsd*
69 AMD x86-64 running GNU/Linux x86_64-*-linux-*
70 Sparc64 running FreeBSD sparc64-*-freebsd*
74 Sanyo XStormy16 xstormy16-elf
76 * OBSOLETE configurations and files
78 Configurations that have been declared obsolete in this release have
79 been commented out. Unless there is activity to revive these
80 configurations, the next release of GDB will have their sources
83 AMD 29k family via UDI a29k-amd-udi, udi29k
84 A29K VxWorks a29k-*-vxworks
85 AMD 29000 embedded, using EBMON a29k-none-none
86 AMD 29000 embedded with COFF a29k-none-coff
87 AMD 29000 embedded with a.out a29k-none-aout
89 testsuite/gdb.hp/gdb.threads-hp/ directory
91 * REMOVED configurations and files
93 TI TMS320C80 tic80-*-*
95 PowerPC Solaris powerpcle-*-solaris*
96 PowerPC Windows NT powerpcle-*-cygwin32
97 PowerPC Netware powerpc-*-netware*
98 Harris/CXUX m88k m88*-harris-cxux*
99 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
100 ns32k-utek-sysv* ns32k-utek-*
101 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
102 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
103 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
104 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
105 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
107 * Changes to command line processing
109 The new `--args' feature can be used to specify command-line arguments
110 for the inferior from gdb's command line.
112 * Changes to key bindings
114 There is a new `operate-and-get-next' function bound to `C-o'.
116 *** Changes in GDB 5.1.1
118 Fix compile problem on DJGPP.
120 Fix a problem with floating-point registers on the i386 being
123 Fix to stop GDB crashing on .debug_str debug info.
125 Numerous documentation fixes.
127 Numerous testsuite fixes.
129 *** Changes in GDB 5.1:
131 * New native configurations
133 Alpha FreeBSD alpha*-*-freebsd*
134 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
135 MIPS GNU/Linux mips*-*-linux*
136 MIPS SGI Irix 6.x mips*-sgi-irix6*
138 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
142 Motorola 68HC11 and 68HC12 m68hc11-elf
144 UltraSparc running GNU/Linux sparc64-*-linux*
146 * OBSOLETE configurations and files
148 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
149 Harris/CXUX m88k m88*-harris-cxux*
150 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
151 ns32k-utek-sysv* ns32k-utek-*
152 TI TMS320C80 tic80-*-*
154 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
155 PowerPC Solaris powerpcle-*-solaris*
156 PowerPC Windows NT powerpcle-*-cygwin32
157 PowerPC Netware powerpc-*-netware*
158 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
159 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
160 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
161 Apple Macintosh (MPW) host N/A
163 stuff.c (Program to stuff files into a specially prepared space in kdb)
164 kdb-start.c (Main loop for the standalone kernel debugger)
166 Configurations that have been declared obsolete in this release have
167 been commented out. Unless there is activity to revive these
168 configurations, the next release of GDB will have their sources
171 * REMOVED configurations and files
173 Altos 3068 m68*-altos-*
174 Convex c1-*-*, c2-*-*
176 ARM RISCix arm-*-* (as host)
180 * GDB has been converted to ISO C.
182 GDB's source code has been converted to ISO C. In particular, the
183 sources are fully protoized, and rely on standard headers being
188 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
190 * The MI enabled by default.
192 The new machine oriented interface (MI) introduced in GDB 5.0 has been
193 revised and enabled by default. Packages which use GDB as a debugging
194 engine behind a UI or another front end are encouraged to switch to
195 using the GDB/MI interface, instead of the old annotations interface
196 which is now deprecated.
198 * Support for debugging Pascal programs.
200 GDB now includes support for debugging Pascal programs. The following
201 main features are supported:
203 - Pascal-specific data types such as sets;
205 - automatic recognition of Pascal sources based on file-name
208 - Pascal-style display of data types, variables, and functions;
210 - a Pascal expression parser.
212 However, some important features are not yet supported.
214 - Pascal string operations are not supported at all;
216 - there are some problems with boolean types;
218 - Pascal type hexadecimal constants are not supported
219 because they conflict with the internal variables format;
221 - support for Pascal objects and classes is not full yet;
223 - unlike Pascal, GDB is case-sensitive for symbol names.
225 * Changes in completion.
227 Commands such as `shell', `run' and `set args', which pass arguments
228 to inferior programs, now complete on file names, similar to what
229 users expect at the shell prompt.
231 Commands which accept locations, such as `disassemble', `print',
232 `breakpoint', `until', etc. now complete on filenames as well as
233 program symbols. Thus, if you type "break foob TAB", and the source
234 files linked into the programs include `foobar.c', that file name will
235 be one of the candidates for completion. However, file names are not
236 considered for completion after you typed a colon that delimits a file
237 name from a name of a function in that file, as in "break foo.c:bar".
239 `set demangle-style' completes on available demangling styles.
241 * New platform-independent commands:
243 It is now possible to define a post-hook for a command as well as a
244 hook that runs before the command. For more details, see the
245 documentation of `hookpost' in the GDB manual.
247 * Changes in GNU/Linux native debugging.
249 Support for debugging multi-threaded programs has been completely
250 revised for all platforms except m68k and sparc. You can now debug as
251 many threads as your system allows you to have.
253 Attach/detach is supported for multi-threaded programs.
255 Support for SSE registers was added for x86. This doesn't work for
256 multi-threaded programs though.
258 * Changes in MIPS configurations.
260 Multi-arch support is enabled for all MIPS configurations.
262 GDB can now be built as native debugger on SGI Irix 6.x systems for
263 debugging n32 executables. (Debugging 64-bit executables is not yet
266 * Unified support for hardware watchpoints in all x86 configurations.
268 Most (if not all) native x86 configurations support hardware-assisted
269 breakpoints and watchpoints in a unified manner. This support
270 implements debug register sharing between watchpoints, which allows to
271 put a virtually infinite number of watchpoints on the same address,
272 and also supports watching regions up to 16 bytes with several debug
275 The new maintenance command `maintenance show-debug-regs' toggles
276 debugging print-outs in functions that insert, remove, and test
277 watchpoints and hardware breakpoints.
279 * Changes in the DJGPP native configuration.
281 New command ``info dos sysinfo'' displays assorted information about
282 the CPU, OS, memory, and DPMI server.
284 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
285 display information about segment descriptors stored in GDT, LDT, and
288 New commands ``info dos pde'' and ``info dos pte'' display entries
289 from Page Directory and Page Tables (for now works with CWSDPMI only).
290 New command ``info dos address-pte'' displays the Page Table entry for
291 a given linear address.
293 GDB can now pass command lines longer than 126 characters to the
294 program being debugged (requires an update to the libdbg.a library
295 which is part of the DJGPP development kit).
297 DWARF2 debug info is now supported.
299 It is now possible to `step' and `next' through calls to `longjmp'.
301 * Changes in documentation.
303 All GDB documentation was converted to GFDL, the GNU Free
304 Documentation License.
306 Tracepoints-related commands are now fully documented in the GDB
309 TUI, the Text-mode User Interface, is now documented in the manual.
311 Tracepoints-related commands are now fully documented in the GDB
314 The "GDB Internals" manual now has an index. It also includes
315 documentation of `ui_out' functions, GDB coding standards, x86
316 hardware watchpoints, and memory region attributes.
318 * GDB's version number moved to ``version.in''
320 The Makefile variable VERSION has been replaced by the file
321 ``version.in''. People creating GDB distributions should update the
322 contents of this file.
326 GUD support is now a standard part of the EMACS distribution.
328 *** Changes in GDB 5.0:
330 * Improved support for debugging FP programs on x86 targets
332 Unified and much-improved support for debugging floating-point
333 programs on all x86 targets. In particular, ``info float'' now
334 displays the FP registers in the same format on all x86 targets, with
335 greater level of detail.
337 * Improvements and bugfixes in hardware-assisted watchpoints
339 It is now possible to watch array elements, struct members, and
340 bitfields with hardware-assisted watchpoints. Data-read watchpoints
341 on x86 targets no longer erroneously trigger when the address is
344 * Improvements in the native DJGPP version of GDB
346 The distribution now includes all the scripts and auxiliary files
347 necessary to build the native DJGPP version on MS-DOS/MS-Windows
348 machines ``out of the box''.
350 The DJGPP version can now debug programs that use signals. It is
351 possible to catch signals that happened in the debuggee, deliver
352 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
353 would kill the program being debugged.) Programs that hook hardware
354 interrupts (keyboard, timer, etc.) can also be debugged.
356 It is now possible to debug DJGPP programs that redirect their
357 standard handles or switch them to raw (as opposed to cooked) mode, or
358 even close them. The command ``run < foo > bar'' works as expected,
359 and ``info terminal'' reports useful information about the debuggee's
360 terminal, including raw/cooked mode, redirection, etc.
362 The DJGPP version now uses termios functions for console I/O, which
363 enables debugging graphics programs. Interrupting GDB with Ctrl-C
366 DOS-style file names with drive letters are now fully supported by
369 It is now possible to debug DJGPP programs that switch their working
370 directory. It is also possible to rerun the debuggee any number of
371 times without restarting GDB; thus, you can use the same setup,
372 breakpoints, etc. for many debugging sessions.
374 * New native configurations
376 ARM GNU/Linux arm*-*-linux*
377 PowerPC GNU/Linux powerpc-*-linux*
381 Motorola MCore mcore-*-*
382 x86 VxWorks i[3456]86-*-vxworks*
383 PowerPC VxWorks powerpc-*-vxworks*
384 TI TMS320C80 tic80-*-*
386 * OBSOLETE configurations
388 Altos 3068 m68*-altos-*
389 Convex c1-*-*, c2-*-*
391 ARM RISCix arm-*-* (as host)
394 Configurations that have been declared obsolete will be commented out,
395 but the code will be left in place. If there is no activity to revive
396 these configurations before the next release of GDB, the sources will
397 be permanently REMOVED.
399 * Gould support removed
401 Support for the Gould PowerNode and NP1 has been removed.
403 * New features for SVR4
405 On SVR4 native platforms (such as Solaris), if you attach to a process
406 without first loading a symbol file, GDB will now attempt to locate and
407 load symbols from the running process's executable file.
409 * Many C++ enhancements
411 C++ support has been greatly improved. Overload resolution now works properly
412 in almost all cases. RTTI support is on the way.
414 * Remote targets can connect to a sub-program
416 A popen(3) style serial-device has been added. This device starts a
417 sub-process (such as a stand-alone simulator) and then communicates
418 with that. The sub-program to run is specified using the syntax
419 ``|<program> <args>'' vis:
421 (gdb) set remotedebug 1
422 (gdb) target extended-remote |mn10300-elf-sim program-args
424 * MIPS 64 remote protocol
426 A long standing bug in the mips64 remote protocol where by GDB
427 expected certain 32 bit registers (ex SR) to be transfered as 32
428 instead of 64 bits has been fixed.
430 The command ``set remote-mips64-transfers-32bit-regs on'' has been
431 added to provide backward compatibility with older versions of GDB.
433 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
435 The command ``set remotebinarydownload'' command has been replaced by
436 ``set remote X-packet''. Other commands in ``set remote'' family
437 include ``set remote P-packet''.
439 * Breakpoint commands accept ranges.
441 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
442 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
443 ``tracepoint passcount'' also accepts a range of tracepoints.
445 * ``apropos'' command added.
447 The ``apropos'' command searches through command names and
448 documentation strings, printing out matches, making it much easier to
449 try to find a command that does what you are looking for.
453 A new machine oriented interface (MI) has been added to GDB. This
454 interface is designed for debug environments running GDB as a separate
455 process. This is part of the long term libGDB project. See the
456 "GDB/MI" chapter of the GDB manual for further information. It can be
457 enabled by configuring with:
459 .../configure --enable-gdbmi
461 *** Changes in GDB-4.18:
463 * New native configurations
465 HP-UX 10.20 hppa*-*-hpux10.20
466 HP-UX 11.x hppa*-*-hpux11.0*
467 M68K GNU/Linux m68*-*-linux*
471 Fujitsu FR30 fr30-*-elf*
472 Intel StrongARM strongarm-*-*
473 Mitsubishi D30V d30v-*-*
475 * OBSOLETE configurations
477 Gould PowerNode, NP1 np1-*-*, pn-*-*
479 Configurations that have been declared obsolete will be commented out,
480 but the code will be left in place. If there is no activity to revive
481 these configurations before the next release of GDB, the sources will
482 be permanently REMOVED.
486 As a compatibility experiment, GDB's source files buildsym.h and
487 buildsym.c have been converted to pure standard C, no longer
488 containing any K&R compatibility code. We believe that all systems in
489 use today either come with a standard C compiler, or have a GCC port
490 available. If this is not true, please report the affected
491 configuration to bug-gdb@gnu.org immediately. See the README file for
492 information about getting a standard C compiler if you don't have one
497 GDB now uses readline 2.2.
499 * set extension-language
501 You can now control the mapping between filename extensions and source
502 languages by using the `set extension-language' command. For instance,
503 you can ask GDB to treat .c files as C++ by saying
504 set extension-language .c c++
505 The command `info extensions' lists all of the recognized extensions
506 and their associated languages.
508 * Setting processor type for PowerPC and RS/6000
510 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
511 you can use the `set processor' command to specify what variant of the
512 PowerPC family you are debugging. The command
516 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
517 following PowerPC and RS6000 variants:
519 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
520 rs6000 IBM RS6000 ("POWER") architecture, user-level view
522 403GC IBM PowerPC 403GC
523 505 Motorola PowerPC 505
524 860 Motorola PowerPC 860 or 850
525 601 Motorola PowerPC 601
526 602 Motorola PowerPC 602
527 603 Motorola/IBM PowerPC 603 or 603e
528 604 Motorola PowerPC 604 or 604e
529 750 Motorola/IBM PowerPC 750 or 750
531 At the moment, this command just tells GDB what to name the
532 special-purpose processor registers. Since almost all the affected
533 registers are inaccessible to user-level programs, this command is
534 only useful for remote debugging in its present form.
538 Thanks to a major code donation from Hewlett-Packard, GDB now has much
539 more extensive support for HP-UX. Added features include shared
540 library support, kernel threads and hardware watchpoints for 11.00,
541 support for HP's ANSI C and C++ compilers, and a compatibility mode
542 for xdb and dbx commands.
546 HP's donation includes the new concept of catchpoints, which is a
547 generalization of the old catch command. On HP-UX, it is now possible
548 to catch exec, fork, and vfork, as well as library loading.
550 This means that the existing catch command has changed; its first
551 argument now specifies the type of catch to be set up. See the
552 output of "help catch" for a list of catchpoint types.
554 * Debugging across forks
556 On HP-UX, you can choose which process to debug when a fork() happens
561 HP has donated a curses-based terminal user interface (TUI). To get
562 it, build with --enable-tui. Although this can be enabled for any
563 configuration, at present it only works for native HP debugging.
565 * GDB remote protocol additions
567 A new protocol packet 'X' that writes binary data is now available.
568 Default behavior is to try 'X', then drop back to 'M' if the stub
569 fails to respond. The settable variable `remotebinarydownload'
570 allows explicit control over the use of 'X'.
572 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
573 full 64-bit address. The command
575 set remoteaddresssize 32
577 can be used to revert to the old behaviour. For existing remote stubs
578 the change should not be noticed, as the additional address information
581 In order to assist in debugging stubs, you may use the maintenance
582 command `packet' to send any text string to the stub. For instance,
584 maint packet heythere
586 sends the packet "$heythere#<checksum>". Note that it is very easy to
587 disrupt a debugging session by sending the wrong packet at the wrong
590 The compare-sections command allows you to compare section data on the
591 target to what is in the executable file without uploading or
592 downloading, by comparing CRC checksums.
594 * Tracing can collect general expressions
596 You may now collect general expressions at tracepoints. This requires
597 further additions to the target-side stub; see tracepoint.c and
598 doc/agentexpr.texi for further details.
600 * mask-address variable for Mips
602 For Mips targets, you may control the zeroing of the upper 32 bits of
603 a 64-bit address by entering `set mask-address on'. This is mainly
604 of interest to users of embedded R4xxx and R5xxx processors.
606 * Higher serial baud rates
608 GDB's serial code now allows you to specify baud rates 57600, 115200,
609 230400, and 460800 baud. (Note that your host system may not be able
610 to achieve all of these rates.)
614 The i960 configuration now includes an initial implementation of a
615 builtin simulator, contributed by Jim Wilson.
618 *** Changes in GDB-4.17:
620 * New native configurations
622 Alpha GNU/Linux alpha*-*-linux*
623 Unixware 2.x i[3456]86-unixware2*
624 Irix 6.x mips*-sgi-irix6*
625 PowerPC GNU/Linux powerpc-*-linux*
626 PowerPC Solaris powerpcle-*-solaris*
627 Sparc GNU/Linux sparc-*-linux*
628 Motorola sysV68 R3V7.1 m68k-motorola-sysv
632 Argonaut Risc Chip (ARC) arc-*-*
633 Hitachi H8/300S h8300*-*-*
634 Matsushita MN10200 w/simulator mn10200-*-*
635 Matsushita MN10300 w/simulator mn10300-*-*
636 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
637 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
638 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
639 Mitsubishi D10V w/simulator d10v-*-*
640 Mitsubishi M32R/D w/simulator m32r-*-elf*
641 Tsqware Sparclet sparclet-*-*
642 NEC V850 w/simulator v850-*-*
644 * New debugging protocols
646 ARM with RDI protocol arm*-*-*
647 M68K with dBUG monitor m68*-*-{aout,coff,elf}
648 DDB and LSI variants of PMON protocol mips*-*-*
649 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
650 PowerPC with SDS protocol powerpc{,le}-*-eabi
651 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
655 All configurations can now understand and use the DWARF 2 debugging
656 format. The choice is automatic, if the symbol file contains DWARF 2
661 GDB now includes basic Java language support. This support is
662 only useful with Java compilers that produce native machine code.
664 * solib-absolute-prefix and solib-search-path
666 For SunOS and SVR4 shared libraries, you may now set the prefix for
667 loading absolute shared library symbol files, and the search path for
668 locating non-absolute shared library symbol files.
670 * Live range splitting
672 GDB can now effectively debug code for which GCC has performed live
673 range splitting as part of its optimization. See gdb/doc/LRS for
674 more details on the expected format of the stabs information.
678 GDB's support for the GNU Hurd, including thread debugging, has been
679 updated to work with current versions of the Hurd.
683 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
684 instruction set. ARM GDB automatically detects when Thumb
685 instructions are in use, and adjusts disassembly and backtracing
690 GDB's MIPS target configurations now handle the MIP16 16-bit
695 GDB now includes support for overlays; if an executable has been
696 linked such that multiple sections are based at the same address, GDB
697 will decide which section to use for symbolic info. You can choose to
698 control the decision manually, using overlay commands, or implement
699 additional target-side support and use "overlay load-target" to bring
700 in the overlay mapping. Do "help overlay" for more detail.
704 The command "info symbol <address>" displays information about
705 the symbol at the specified address.
709 The standard remote protocol now includes an extension that allows
710 asynchronous collection and display of trace data. This requires
711 extensive support in the target-side debugging stub. Tracing mode
712 includes a new interaction mode in GDB and new commands: see the
713 file tracepoint.c for more details.
717 Configurations for embedded MIPS now include a simulator contributed
718 by Cygnus Solutions. The simulator supports the instruction sets
719 of most MIPS variants.
723 Sparc configurations may now include the ERC32 simulator contributed
724 by the European Space Agency. The simulator is not built into
725 Sparc targets by default; configure with --enable-sim to include it.
729 For target configurations that may include multiple variants of a
730 basic architecture (such as MIPS and SH), you may now set the
731 architecture explicitly. "set arch" sets, "info arch" lists
732 the possible architectures.
734 *** Changes in GDB-4.16:
736 * New native configurations
738 Windows 95, x86 Windows NT i[345]86-*-cygwin32
739 M68K NetBSD m68k-*-netbsd*
740 PowerPC AIX 4.x powerpc-*-aix*
741 PowerPC MacOS powerpc-*-macos*
742 PowerPC Windows NT powerpcle-*-cygwin32
743 RS/6000 AIX 4.x rs6000-*-aix4*
747 ARM with RDP protocol arm-*-*
748 I960 with MON960 i960-*-coff
749 MIPS VxWorks mips*-*-vxworks*
750 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
751 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
753 Matra Sparclet sparclet-*-*
757 The powerpc-eabi configuration now includes the PSIM simulator,
758 contributed by Andrew Cagney, with assistance from Mike Meissner.
759 PSIM is a very elaborate model of the PowerPC, including not only
760 basic instruction set execution, but also details of execution unit
761 performance and I/O hardware. See sim/ppc/README for more details.
765 GDB now works with Solaris 2.5.
767 * Windows 95/NT native
769 GDB will now work as a native debugger on Windows 95 and Windows NT.
770 To build it from source, you must use the "gnu-win32" environment,
771 which uses a DLL to emulate enough of Unix to run the GNU tools.
772 Further information, binaries, and sources are available at
773 ftp.cygnus.com, under pub/gnu-win32.
775 * dont-repeat command
777 If a user-defined command includes the command `dont-repeat', then the
778 command will not be repeated if the user just types return. This is
779 useful if the command is time-consuming to run, so that accidental
780 extra keystrokes don't run the same command many times.
782 * Send break instead of ^C
784 The standard remote protocol now includes an option to send a break
785 rather than a ^C to the target in order to interrupt it. By default,
786 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
788 * Remote protocol timeout
790 The standard remote protocol includes a new variable `remotetimeout'
791 that allows you to set the number of seconds before GDB gives up trying
792 to read from the target. The default value is 2.
794 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
796 By default GDB will automatically keep track of objects as they are
797 loaded and unloaded by the dynamic linker. By using the command `set
798 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
799 when shared library events occur, thus allowing you to set breakpoints
800 in shared libraries which are explicitly loaded by the inferior.
802 Note this feature does not work on hpux8. On hpux9 you must link
803 /usr/lib/end.o into your program. This feature should work
804 automatically on hpux10.
806 * Irix 5.x hardware watchpoint support
808 Irix 5 configurations now support the use of hardware watchpoints.
810 * Mips protocol "SYN garbage limit"
812 When debugging a Mips target using the `target mips' protocol, you
813 may set the number of characters that GDB will ignore by setting
814 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
815 every character. The default value is 1050.
817 * Recording and replaying remote debug sessions
819 If you set `remotelogfile' to the name of a file, gdb will write to it
820 a recording of a remote debug session. This recording may then be
821 replayed back to gdb using "gdbreplay". See gdbserver/README for
822 details. This is useful when you have a problem with GDB while doing
823 remote debugging; you can make a recording of the session and send it
824 to someone else, who can then recreate the problem.
826 * Speedups for remote debugging
828 GDB includes speedups for downloading and stepping MIPS systems using
829 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
830 and more efficient S-record downloading.
832 * Memory use reductions and statistics collection
834 GDB now uses less memory and reports statistics about memory usage.
835 Try the `maint print statistics' command, for example.
837 *** Changes in GDB-4.15:
841 The symbol reader for AIX GDB now uses partial symbol tables. This
842 can greatly improve startup time, especially for large executables.
844 * Remote targets use caching
846 Remote targets now use a data cache to speed up communication with the
847 remote side. The data cache could lead to incorrect results because
848 it doesn't know about volatile variables, thus making it impossible to
849 debug targets which use memory mapped I/O devices. `set remotecache
850 off' turns the the data cache off.
852 * Remote targets may have threads
854 The standard remote protocol now includes support for multiple threads
855 in the target system, using new protocol commands 'H' and 'T'. See
856 gdb/remote.c for details.
860 If GDB is configured with `--enable-netrom', then it will include
861 support for the NetROM ROM emulator from XLNT Designs. The NetROM
862 acts as though it is a bank of ROM on the target board, but you can
863 write into it over the network. GDB's support consists only of
864 support for fast loading into the emulated ROM; to debug, you must use
865 another protocol, such as standard remote protocol. The usual
866 sequence is something like
868 target nrom <netrom-hostname>
870 target remote <netrom-hostname>:1235
874 GDB now includes support for the Apple Macintosh, as a host only. It
875 may be run as either an MPW tool or as a standalone application, and
876 it can debug through the serial port. All the usual GDB commands are
877 available, but to the target command, you must supply "serial" as the
878 device type instead of "/dev/ttyXX". See mpw-README in the main
879 directory for more information on how to build. The MPW configuration
880 scripts */mpw-config.in support only a few targets, and only the
881 mips-idt-ecoff target has been tested.
885 GDB configuration now uses autoconf. This is not user-visible,
886 but does simplify configuration and building.
890 GDB now supports hpux10.
892 *** Changes in GDB-4.14:
894 * New native configurations
896 x86 FreeBSD i[345]86-*-freebsd
897 x86 NetBSD i[345]86-*-netbsd
898 NS32k NetBSD ns32k-*-netbsd
899 Sparc NetBSD sparc-*-netbsd
903 A29K VxWorks a29k-*-vxworks
904 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
905 CPU32 EST-300 emulator m68*-*-est*
906 PowerPC ELF powerpc-*-elf
909 * Alpha OSF/1 support for procfs
911 GDB now supports procfs under OSF/1-2.x and higher, which makes it
912 possible to attach to running processes. As the mounting of the /proc
913 filesystem is optional on the Alpha, GDB automatically determines
914 the availability of /proc during startup. This can lead to problems
915 if /proc is unmounted after GDB has been started.
917 * Arguments to user-defined commands
919 User commands may accept up to 10 arguments separated by whitespace.
920 Arguments are accessed within the user command via $arg0..$arg9. A
923 print $arg0 + $arg1 + $arg2
925 To execute the command use:
928 Defines the command "adder" which prints the sum of its three arguments.
929 Note the arguments are text substitutions, so they may reference variables,
930 use complex expressions, or even perform inferior function calls.
932 * New `if' and `while' commands
934 This makes it possible to write more sophisticated user-defined
935 commands. Both commands take a single argument, which is the
936 expression to evaluate, and must be followed by the commands to
937 execute, one per line, if the expression is nonzero, the list being
938 terminated by the word `end'. The `if' command list may include an
939 `else' word, which causes the following commands to be executed only
940 if the expression is zero.
942 * Fortran source language mode
944 GDB now includes partial support for Fortran 77. It will recognize
945 Fortran programs and can evaluate a subset of Fortran expressions, but
946 variables and functions may not be handled correctly. GDB will work
947 with G77, but does not yet know much about symbols emitted by other
950 * Better HPUX support
952 Most debugging facilities now work on dynamic executables for HPPAs
953 running hpux9 or later. You can attach to running dynamically linked
954 processes, but by default the dynamic libraries will be read-only, so
955 for instance you won't be able to put breakpoints in them. To change
956 that behavior do the following before running the program:
962 This will cause the libraries to be mapped private and read-write.
963 To revert to the normal behavior, do this:
969 You cannot set breakpoints or examine data in the library until after
970 the library is loaded if the function/data symbols do not have
973 GDB can now also read debug symbols produced by the HP C compiler on
974 HPPAs (sorry, no C++, Fortran or 68k support).
976 * Target byte order now dynamically selectable
978 You can choose which byte order to use with a target system, via the
979 commands "set endian big" and "set endian little", and you can see the
980 current setting by using "show endian". You can also give the command
981 "set endian auto", in which case GDB will use the byte order
982 associated with the executable. Currently, only embedded MIPS
983 configurations support dynamic selection of target byte order.
985 * New DOS host serial code
987 This version uses DPMI interrupts to handle buffered I/O, so you
988 no longer need to run asynctsr when debugging boards connected to
991 *** Changes in GDB-4.13:
993 * New "complete" command
995 This lists all the possible completions for the rest of the line, if it
996 were to be given as a command itself. This is intended for use by emacs.
998 * Trailing space optional in prompt
1000 "set prompt" no longer adds a space for you after the prompt you set. This
1001 allows you to set a prompt which ends in a space or one that does not.
1003 * Breakpoint hit counts
1005 "info break" now displays a count of the number of times the breakpoint
1006 has been hit. This is especially useful in conjunction with "ignore"; you
1007 can ignore a large number of breakpoint hits, look at the breakpoint info
1008 to see how many times the breakpoint was hit, then run again, ignoring one
1009 less than that number, and this will get you quickly to the last hit of
1012 * Ability to stop printing at NULL character
1014 "set print null-stop" will cause GDB to stop printing the characters of
1015 an array when the first NULL is encountered. This is useful when large
1016 arrays actually contain only short strings.
1018 * Shared library breakpoints
1020 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
1021 breakpoints in shared libraries before the executable is run.
1023 * Hardware watchpoints
1025 There is a new hardware breakpoint for the watch command for sparclite
1026 targets. See gdb/sparclite/hw_breakpoint.note.
1028 Hardware watchpoints are also now supported under GNU/Linux.
1032 Annotations have been added. These are for use with graphical interfaces,
1033 and are still experimental. Currently only gdba.el uses these.
1035 * Improved Irix 5 support
1037 GDB now works properly with Irix 5.2.
1039 * Improved HPPA support
1041 GDB now works properly with the latest GCC and GAS.
1043 * New native configurations
1045 Sequent PTX4 i[34]86-sequent-ptx4
1046 HPPA running OSF/1 hppa*-*-osf*
1047 Atari TT running SVR4 m68*-*-sysv4*
1048 RS/6000 LynxOS rs6000-*-lynxos*
1052 OS/9000 i[34]86-*-os9k
1053 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
1056 * Hitachi SH7000 and E7000-PC ICE support
1058 There is now support for communicating with the Hitachi E7000-PC ICE.
1059 This is available automatically when GDB is configured for the SH.
1063 As usual, a variety of small fixes and improvements, both generic
1064 and configuration-specific. See the ChangeLog for more detail.
1066 *** Changes in GDB-4.12:
1068 * Irix 5 is now supported
1072 GDB-4.12 on the HPPA has a number of changes which make it unable
1073 to debug the output from the currently released versions of GCC and
1074 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
1075 of GCC and GAS, versions of these tools designed to work with GDB-4.12
1076 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
1079 *** Changes in GDB-4.11:
1081 * User visible changes:
1085 The "set remotedebug" option is now consistent between the mips remote
1086 target, remote targets using the gdb-specific protocol, UDI (AMD's
1087 debug protocol for the 29k) and the 88k bug monitor. It is now an
1088 integer specifying a debug level (normally 0 or 1, but 2 means more
1089 debugging info for the mips target).
1091 * DEC Alpha native support
1093 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
1094 debug info, but GDB works fairly well with the DEC compiler and should
1095 work with a future GCC release. See the README file for a few
1096 Alpha-specific notes.
1098 * Preliminary thread implementation
1100 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
1102 * LynxOS native and target support for 386
1104 This release has been hosted on LynxOS 2.2, and also can be configured
1105 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
1108 * Improvements in C++ mangling/demangling.
1110 This release has much better g++ debugging, specifically in name
1111 mangling/demangling, virtual function calls, print virtual table,
1112 call methods, ...etc.
1114 *** Changes in GDB-4.10:
1116 * User visible changes:
1118 Remote debugging using the GDB-specific (`target remote') protocol now
1119 supports the `load' command. This is only useful if you have some
1120 other way of getting the stub to the target system, and you can put it
1121 somewhere in memory where it won't get clobbered by the download.
1123 Filename completion now works.
1125 When run under emacs mode, the "info line" command now causes the
1126 arrow to point to the line specified. Also, "info line" prints
1127 addresses in symbolic form (as well as hex).
1129 All vxworks based targets now support a user settable option, called
1130 vxworks-timeout. This option represents the number of seconds gdb
1131 should wait for responses to rpc's. You might want to use this if
1132 your vxworks target is, perhaps, a slow software simulator or happens
1133 to be on the far side of a thin network line.
1137 This release contains support for using a DEC alpha as a GDB host for
1138 cross debugging. Native alpha debugging is not supported yet.
1141 *** Changes in GDB-4.9:
1145 This is the first GDB release which is accompanied by a matching testsuite.
1146 The testsuite requires installation of dejagnu, which should be available
1147 via ftp from most sites that carry GNU software.
1151 'Cfront' style demangling has had its name changed to 'ARM' style, to
1152 emphasize that it was written from the specifications in the C++ Annotated
1153 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
1154 disclaimers, it still generated too much confusion with users attempting to
1155 use gdb with AT&T cfront.
1159 GDB now uses a standard remote interface to a simulator library.
1160 So far, the library contains simulators for the Zilog Z8001/2, the
1161 Hitachi H8/300, H8/500 and Super-H.
1163 * New targets supported
1165 H8/300 simulator h8300-hitachi-hms or h8300hms
1166 H8/500 simulator h8500-hitachi-hms or h8500hms
1167 SH simulator sh-hitachi-hms or sh
1168 Z8000 simulator z8k-zilog-none or z8ksim
1169 IDT MIPS board over serial line mips-idt-ecoff
1171 Cross-debugging to GO32 targets is supported. It requires a custom
1172 version of the i386-stub.c module which is integrated with the
1173 GO32 memory extender.
1175 * New remote protocols
1177 MIPS remote debugging protocol.
1179 * New source languages supported
1181 This version includes preliminary support for Chill, a Pascal like language
1182 used by telecommunications companies. Chill support is also being integrated
1183 into the GNU compiler, but we don't know when it will be publically available.
1186 *** Changes in GDB-4.8:
1188 * HP Precision Architecture supported
1190 GDB now supports HP PA-RISC machines running HPUX. A preliminary
1191 version of this support was available as a set of patches from the
1192 University of Utah. GDB does not support debugging of programs
1193 compiled with the HP compiler, because HP will not document their file
1194 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
1195 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
1197 Many problems in the preliminary version have been fixed.
1199 * Faster and better demangling
1201 We have improved template demangling and fixed numerous bugs in the GNU style
1202 demangler. It can now handle type modifiers such as `static' or `const'. Wide
1203 character types (wchar_t) are now supported. Demangling of each symbol is now
1204 only done once, and is cached when the symbol table for a file is read in.
1205 This results in a small increase in memory usage for C programs, a moderate
1206 increase in memory usage for C++ programs, and a fantastic speedup in
1209 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
1210 from the specifications in the Annotated Reference Manual, which AT&T's
1211 compiler does not actually implement.
1213 * G++ multiple inheritance compiler problem
1215 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
1216 inheritance lattices was reworked to properly discover ambiguities. We
1217 recently found an example which causes this new algorithm to fail in a
1218 very subtle way, producing bad debug information for those classes.
1219 The file 'gcc.patch' (in this directory) can be applied to gcc to
1220 circumvent the problem. A future GCC release will contain a complete
1223 The previous G++ debug info problem (mentioned below for the gdb-4.7
1224 release) is fixed in gcc version 2.3.2.
1226 * Improved configure script
1228 The `configure' script will now attempt to guess your system type if
1229 you don't supply a host system type. The old scheme of supplying a
1230 host system triplet is preferable over using this. All the magic is
1231 done in the new `config.guess' script. Examine it for details.
1233 We have also brought our configure script much more in line with the FSF's
1234 version. It now supports the --with-xxx options. In particular,
1235 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
1236 The resulting GDB will not be able to read arbitrary object file formats --
1237 only the format ``expected'' to be used on the configured target system.
1238 We hope to make this the default in a future release.
1240 * Documentation improvements
1242 There's new internal documentation on how to modify GDB, and how to
1243 produce clean changes to the code. We implore people to read it
1244 before submitting changes.
1246 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
1247 M4 macros. The new texinfo.tex is provided in this release. Pre-built
1248 `info' files are also provided. To build `info' files from scratch,
1249 you will need the latest `makeinfo' release, which will be available in
1250 a future texinfo-X.Y release.
1252 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
1253 We're not sure exactly which versions have this problem, but it has
1254 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
1255 or better. If that isn't possible, there is a patch in
1256 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
1257 around this problem.
1261 GDB now supports array constants that can be used in expressions typed in by
1262 the user. The syntax is `{element, element, ...}'. Ie: you can now type
1263 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
1266 The new directory `gdb/sparclite' contains a program that demonstrates
1267 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
1269 * New native hosts supported
1271 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
1272 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
1274 * New targets supported
1276 AMD 29k family via UDI a29k-amd-udi or udi29k
1278 * New file formats supported
1280 BFD now supports reading HP/PA-RISC executables (SOM file format?),
1281 HPUX core files, and SCO 3.2v2 core files.
1285 Attaching to processes now works again; thanks for the many bug reports.
1287 We have also stomped on a bunch of core dumps caused by
1288 printf_filtered("%s") problems.
1290 We eliminated a copyright problem on the rpc and ptrace header files
1291 for VxWorks, which was discovered at the last minute during the 4.7
1292 release. You should now be able to build a VxWorks GDB.
1294 You can now interrupt gdb while an attached process is running. This
1295 will cause the attached process to stop, and give control back to GDB.
1297 We fixed problems caused by using too many file descriptors
1298 for reading symbols from object files and libraries. This was
1299 especially a problem for programs that used many (~100) shared
1302 The `step' command now only enters a subroutine if there is line number
1303 information for the subroutine. Otherwise it acts like the `next'
1304 command. Previously, `step' would enter subroutines if there was
1305 any debugging information about the routine. This avoids problems
1306 when using `cc -g1' on MIPS machines.
1308 * Internal improvements
1310 GDB's internal interfaces have been improved to make it easier to support
1311 debugging of multiple languages in the future.
1313 GDB now uses a common structure for symbol information internally.
1314 Minimal symbols (derived from linkage symbols in object files), partial
1315 symbols (from a quick scan of debug information), and full symbols
1316 contain a common subset of information, making it easier to write
1317 shared code that handles any of them.
1319 * New command line options
1321 We now accept --silent as an alias for --quiet.
1325 The memory-mapped-malloc library is now licensed under the GNU Library
1326 General Public License.
1328 *** Changes in GDB-4.7:
1330 * Host/native/target split
1332 GDB has had some major internal surgery to untangle the support for
1333 hosts and remote targets. Now, when you configure GDB for a remote
1334 target, it will no longer load in all of the support for debugging
1335 local programs on the host. When fully completed and tested, this will
1336 ensure that arbitrary host/target combinations are possible.
1338 The primary conceptual shift is to separate the non-portable code in
1339 GDB into three categories. Host specific code is required any time GDB
1340 is compiled on that host, regardless of the target. Target specific
1341 code relates to the peculiarities of the target, but can be compiled on
1342 any host. Native specific code is everything else: it can only be
1343 built when the host and target are the same system. Child process
1344 handling and core file support are two common `native' examples.
1346 GDB's use of /proc for controlling Unix child processes is now cleaner.
1347 It has been split out into a single module under the `target_ops' vector,
1348 plus two native-dependent functions for each system that uses /proc.
1350 * New hosts supported
1352 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
1353 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1354 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
1356 * New targets supported
1358 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1359 68030 and CPU32 m68030-*-*, m68332-*-*
1361 * New native hosts supported
1363 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1364 (386bsd is not well tested yet)
1365 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
1367 * New file formats supported
1369 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
1370 supports reading of `a.out.adobe' object files, which are an a.out
1371 format extended with minimal information about multiple sections.
1375 `show copying' is the same as the old `info copying'.
1376 `show warranty' is the same as `info warrantee'.
1377 These were renamed for consistency. The old commands continue to work.
1379 `info handle' is a new alias for `info signals'.
1381 You can now define pre-command hooks, which attach arbitrary command
1382 scripts to any command. The commands in the hook will be executed
1383 prior to the user's command. You can also create a hook which will be
1384 executed whenever the program stops. See gdb.texinfo.
1388 We now deal with Cfront style name mangling, and can even extract type
1389 info from mangled symbols. GDB can automatically figure out which
1390 symbol mangling style your C++ compiler uses.
1392 Calling of methods and virtual functions has been improved as well.
1396 The crash that occured when debugging Sun Ansi-C compiled binaries is
1397 fixed. This was due to mishandling of the extra N_SO stabs output
1400 We also finally got Ultrix 4.2 running in house, and fixed core file
1401 support, with help from a dozen people on the net.
1403 John M. Farrell discovered that the reason that single-stepping was so
1404 slow on all of the Mips based platforms (primarily SGI and DEC) was
1405 that we were trying to demangle and lookup a symbol used for internal
1406 purposes on every instruction that was being stepped through. Changing
1407 the name of that symbol so that it couldn't be mistaken for a C++
1408 mangled symbol sped things up a great deal.
1410 Rich Pixley sped up symbol lookups in general by getting much smarter
1411 about when C++ symbol mangling is necessary. This should make symbol
1412 completion (TAB on the command line) much faster. It's not as fast as
1413 we'd like, but it's significantly faster than gdb-4.6.
1417 A new user controllable variable 'call_scratch_address' can
1418 specify the location of a scratch area to be used when GDB
1419 calls a function in the target. This is necessary because the
1420 usual method of putting the scratch area on the stack does not work
1421 in systems that have separate instruction and data spaces.
1423 We integrated changes to support the 29k UDI (Universal Debugger
1424 Interface), but discovered at the last minute that we didn't have all
1425 of the appropriate copyright paperwork. We are working with AMD to
1426 resolve this, and hope to have it available soon.
1430 We have sped up the remote serial line protocol, especially for targets
1431 with lots of registers. It now supports a new `expedited status' ('T')
1432 message which can be used in place of the existing 'S' status message.
1433 This allows the remote stub to send only the registers that GDB
1434 needs to make a quick decision about single-stepping or conditional
1435 breakpoints, eliminating the need to fetch the entire register set for
1436 each instruction being stepped through.
1438 The GDB remote serial protocol now implements a write-through cache for
1439 registers, only re-reading the registers if the target has run.
1441 There is also a new remote serial stub for SPARC processors. You can
1442 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
1443 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
1444 processor with a serial port.
1448 Configure.in files have become much easier to read and modify. A new
1449 `table driven' format makes it more obvious what configurations are
1450 supported, and what files each one uses.
1454 There is a new opcodes library which will eventually contain all of the
1455 disassembly routines and opcode tables. At present, it only contains
1456 Sparc and Z8000 routines. This will allow the assembler, debugger, and
1457 disassembler (binutils/objdump) to share these routines.
1459 The libiberty library is now copylefted under the GNU Library General
1460 Public License. This allows more liberal use, and was done so libg++
1461 can use it. This makes no difference to GDB, since the Library License
1462 grants all the rights from the General Public License.
1466 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
1467 reference to the stabs symbol info used by the debugger. It is (as far
1468 as we know) the only published document on this fascinating topic. We
1469 encourage you to read it, compare it to the stabs information on your
1470 system, and send improvements on the document in general (to
1471 bug-gdb@prep.ai.mit.edu).
1473 And, of course, many bugs have been fixed.
1476 *** Changes in GDB-4.6:
1478 * Better support for C++ function names
1480 GDB now accepts as input the "demangled form" of C++ overloaded function
1481 names and member function names, and can do command completion on such names
1482 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
1483 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
1484 Make use of command completion, it is your friend.
1486 GDB also now accepts a variety of C++ mangled symbol formats. They are
1487 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
1488 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
1489 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
1490 for the list of formats.
1492 * G++ symbol mangling problem
1494 Recent versions of gcc have a bug in how they emit debugging information for
1495 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
1496 directory) can be applied to gcc to fix the problem. Alternatively, if you
1497 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
1498 usual symptom is difficulty with setting breakpoints on methods. GDB complains
1499 about the method being non-existent. (We believe that version 2.2.2 of GCC has
1502 * New 'maintenance' command
1504 All of the commands related to hacking GDB internals have been moved out of
1505 the main command set, and now live behind the 'maintenance' command. This
1506 can also be abbreviated as 'mt'. The following changes were made:
1508 dump-me -> maintenance dump-me
1509 info all-breakpoints -> maintenance info breakpoints
1510 printmsyms -> maintenance print msyms
1511 printobjfiles -> maintenance print objfiles
1512 printpsyms -> maintenance print psymbols
1513 printsyms -> maintenance print symbols
1515 The following commands are new:
1517 maintenance demangle Call internal GDB demangler routine to
1518 demangle a C++ link name and prints the result.
1519 maintenance print type Print a type chain for a given symbol
1521 * Change to .gdbinit file processing
1523 We now read the $HOME/.gdbinit file before processing the argv arguments
1524 (e.g. reading symbol files or core files). This allows global parameters to
1525 be set, which will apply during the symbol reading. The ./.gdbinit is still
1526 read after argv processing.
1528 * New hosts supported
1530 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
1532 GNU/Linux support i386-unknown-linux or linux
1534 We are also including code to support the HP/PA running BSD and HPUX. This
1535 is almost guaranteed not to work, as we didn't have time to test or build it
1536 for this release. We are including it so that the more adventurous (or
1537 masochistic) of you can play with it. We also had major problems with the
1538 fact that the compiler that we got from HP doesn't support the -g option.
1541 * New targets supported
1543 Hitachi H8/300 h8300-hitachi-hms or h8300hms
1545 * More smarts about finding #include files
1547 GDB now remembers the compilation directory for all include files, and for
1548 all files from which C is generated (like yacc and lex sources). This
1549 greatly improves GDB's ability to find yacc/lex sources, and include files,
1550 especially if you are debugging your program from a directory different from
1551 the one that contains your sources.
1553 We also fixed a bug which caused difficulty with listing and setting
1554 breakpoints in include files which contain C code. (In the past, you had to
1555 try twice in order to list an include file that you hadn't looked at before.)
1557 * Interesting infernals change
1559 GDB now deals with arbitrary numbers of sections, where the symbols for each
1560 section must be relocated relative to that section's landing place in the
1561 target's address space. This work was needed to support ELF with embedded
1562 stabs used by Solaris-2.0.
1564 * Bug fixes (of course!)
1566 There have been loads of fixes for the following things:
1567 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
1568 i960, stabs, DOS(GO32), procfs, etc...
1570 See the ChangeLog for details.
1572 *** Changes in GDB-4.5:
1574 * New machines supported (host and target)
1576 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
1578 SGI Irix-4.x mips-sgi-irix4 or iris4
1580 * New malloc package
1582 GDB now uses a new memory manager called mmalloc, based on gmalloc.
1583 Mmalloc is capable of handling mutiple heaps of memory. It is also
1584 capable of saving a heap to a file, and then mapping it back in later.
1585 This can be used to greatly speedup the startup of GDB by using a
1586 pre-parsed symbol table which lives in a mmalloc managed heap. For
1587 more details, please read mmalloc/mmalloc.texi.
1591 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
1592 'help info proc' for details.
1594 * MIPS ecoff symbol table format
1596 The code that reads MIPS symbol table format is now supported on all hosts.
1597 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
1600 * File name changes for MS-DOS
1602 Many files in the config directories have been renamed to make it easier to
1603 support GDB on MS-DOSe systems (which have very restrictive file name
1604 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
1605 environment) is close to working but has some remaining problems. Note
1606 that debugging of DOS programs is not supported, due to limitations
1607 in the ``operating system'', but it can be used to host cross-debugging.
1609 * Cross byte order fixes
1611 Many fixes have been made to support cross debugging of Sparc and MIPS
1612 targets from hosts whose byte order differs.
1614 * New -mapped and -readnow options
1616 If memory-mapped files are available on your system through the 'mmap'
1617 system call, you can use the -mapped option on the `file' or
1618 `symbol-file' commands to cause GDB to write the symbols from your
1619 program into a reusable file. If the program you are debugging is
1620 called `/path/fred', the mapped symbol file will be `./fred.syms'.
1621 Future GDB debugging sessions will notice the presence of this file,
1622 and will quickly map in symbol information from it, rather than reading
1623 the symbol table from the executable program. Using the '-mapped'
1624 option in a GDB `file' or `symbol-file' command has the same effect as
1625 starting GDB with the '-mapped' command-line option.
1627 You can cause GDB to read the entire symbol table immediately by using
1628 the '-readnow' option with any of the commands that load symbol table
1629 information (or on the GDB command line). This makes the command
1630 slower, but makes future operations faster.
1632 The -mapped and -readnow options are typically combined in order to
1633 build a `fred.syms' file that contains complete symbol information.
1634 A simple GDB invocation to do nothing but build a `.syms' file for future
1637 gdb -batch -nx -mapped -readnow programname
1639 The `.syms' file is specific to the host machine on which GDB is run.
1640 It holds an exact image of GDB's internal symbol table. It cannot be
1641 shared across multiple host platforms.
1643 * longjmp() handling
1645 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
1646 siglongjmp() without losing control. This feature has not yet been ported to
1647 all systems. It currently works on many 386 platforms, all MIPS-based
1648 platforms (SGI, DECstation, etc), and Sun3/4.
1652 Preliminary work has been put in to support the new Solaris OS from Sun. At
1653 this time, it can control and debug processes, but it is not capable of
1658 As always, many many bug fixes. The major areas were with g++, and mipsread.
1659 People using the MIPS-based platforms should experience fewer mysterious
1660 crashes and trashed symbol tables.
1662 *** Changes in GDB-4.4:
1664 * New machines supported (host and target)
1666 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1668 BSD Reno on Vax vax-dec-bsd
1669 Ultrix on Vax vax-dec-ultrix
1671 * New machines supported (target)
1673 AMD 29000 embedded, using EBMON a29k-none-none
1677 GDB continues to improve its handling of C++. `References' work better.
1678 The demangler has also been improved, and now deals with symbols mangled as
1679 per the Annotated C++ Reference Guide.
1681 GDB also now handles `stabs' symbol information embedded in MIPS
1682 `ecoff' symbol tables. Since the ecoff format was not easily
1683 extensible to handle new languages such as C++, this appeared to be a
1684 good way to put C++ debugging info into MIPS binaries. This option
1685 will be supported in the GNU C compiler, version 2, when it is
1688 * New features for SVR4
1690 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
1691 shared libraries. Debugging dynamically linked programs should present
1692 only minor differences from debugging statically linked programs.
1694 The `info proc' command will print out information about any process
1695 on an SVR4 system (including the one you are debugging). At the moment,
1696 it prints the address mappings of the process.
1698 If you bring up GDB on another SVR4 system, please send mail to
1699 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
1701 * Better dynamic linking support in SunOS
1703 Reading symbols from shared libraries which contain debugging symbols
1704 now works properly. However, there remain issues such as automatic
1705 skipping of `transfer vector' code during function calls, which
1706 make it harder to debug code in a shared library, than to debug the
1707 same code linked statically.
1711 GDB is now using the latest `getopt' routines from the FSF. This
1712 version accepts the -- prefix for options with long names. GDB will
1713 continue to accept the old forms (-option and +option) as well.
1714 Various single letter abbreviations for options have been explicity
1715 added to the option table so that they won't get overshadowed in the
1716 future by other options that begin with the same letter.
1720 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
1721 Many assorted bugs have been handled. Many more remain to be handled.
1722 See the various ChangeLog files (primarily in gdb and bfd) for details.
1725 *** Changes in GDB-4.3:
1727 * New machines supported (host and target)
1729 Amiga 3000 running Amix m68k-cbm-svr4 or amix
1730 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
1731 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1733 * Almost SCO Unix support
1735 We had hoped to support:
1736 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1737 (except for core file support), but we discovered very late in the release
1738 that it has problems with process groups that render gdb unusable. Sorry
1739 about that. I encourage people to fix it and post the fixes.
1741 * Preliminary ELF and DWARF support
1743 GDB can read ELF object files on System V Release 4, and can handle
1744 debugging records for C, in DWARF format, in ELF files. This support
1745 is preliminary. If you bring up GDB on another SVR4 system, please
1746 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
1751 GDB now uses the latest `readline' library. One user-visible change
1752 is that two tabs will list possible command completions, which previously
1753 required typing M-? (meta-question mark, or ESC ?).
1757 The `stepi' bug that many of you noticed has been squashed.
1758 Many bugs in C++ have been handled. Many more remain to be handled.
1759 See the various ChangeLog files (primarily in gdb and bfd) for details.
1761 * State of the MIPS world (in case you wondered):
1763 GDB can understand the symbol tables emitted by the compilers
1764 supplied by most vendors of MIPS-based machines, including DEC. These
1765 symbol tables are in a format that essentially nobody else uses.
1767 Some versions of gcc come with an assembler post-processor called
1768 mips-tfile. This program is required if you want to do source-level
1769 debugging of gcc-compiled programs. I believe FSF does not ship
1770 mips-tfile with gcc version 1, but it will eventually come with gcc
1773 Debugging of g++ output remains a problem. g++ version 1.xx does not
1774 really support it at all. (If you're lucky, you should be able to get
1775 line numbers and stack traces to work, but no parameters or local
1776 variables.) With some work it should be possible to improve the
1779 When gcc version 2 is released, you will have somewhat better luck.
1780 However, even then you will get confusing results for inheritance and
1783 We will eventually provide full debugging of g++ output on
1784 DECstations. This will probably involve some kind of stabs-in-ecoff
1785 encapulation, but the details have not been worked out yet.
1788 *** Changes in GDB-4.2:
1790 * Improved configuration
1792 Only one copy of `configure' exists now, and it is not self-modifying.
1793 Porting BFD is simpler.
1797 The `step' and `next' commands now only stop at the first instruction
1798 of a source line. This prevents the multiple stops that used to occur
1799 in switch statements, for-loops, etc. `Step' continues to stop if a
1800 function that has debugging information is called within the line.
1804 Lots of small bugs fixed. More remain.
1806 * New host supported (not target)
1808 Intel 386 PC clone running Mach i386-none-mach
1811 *** Changes in GDB-4.1:
1813 * Multiple source language support
1815 GDB now has internal scaffolding to handle several source languages.
1816 It determines the type of each source file from its filename extension,
1817 and will switch expression parsing and number formatting to match the
1818 language of the function in the currently selected stack frame.
1819 You can also specifically set the language to be used, with
1820 `set language c' or `set language modula-2'.
1824 GDB now has preliminary support for the GNU Modula-2 compiler,
1825 currently under development at the State University of New York at
1826 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
1827 continue through the fall of 1991 and into 1992.
1829 Other Modula-2 compilers are currently not supported, and attempting to
1830 debug programs compiled with them will likely result in an error as the
1831 symbol table is read. Feel free to work on it, though!
1833 There are hooks in GDB for strict type checking and range checking,
1834 in the `Modula-2 philosophy', but they do not currently work.
1838 GDB can now write to executable and core files (e.g. patch
1839 a variable's value). You must turn this switch on, specify
1840 the file ("exec foo" or "core foo"), *then* modify it, e.g.
1841 by assigning a new value to a variable. Modifications take
1844 * Automatic SunOS shared library reading
1846 When you run your program, GDB automatically determines where its
1847 shared libraries (if any) have been loaded, and reads their symbols.
1848 The `share' command is no longer needed. This also works when
1849 examining core files.
1853 You can specify the number of lines that the `list' command shows.
1856 * New machines supported (host and target)
1858 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1859 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
1860 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
1862 * New hosts supported (not targets)
1864 IBM RT/PC: romp-ibm-aix or rtpc
1866 * New targets supported (not hosts)
1868 AMD 29000 embedded with COFF a29k-none-coff
1869 AMD 29000 embedded with a.out a29k-none-aout
1870 Ultracomputer remote kernel debug a29k-nyu-kern
1872 * New remote interfaces
1878 *** Changes in GDB-4.0:
1882 Wide output is wrapped at good places to make the output more readable.
1884 Gdb now supports cross-debugging from a host machine of one type to a
1885 target machine of another type. Communication with the target system
1886 is over serial lines. The ``target'' command handles connecting to the
1887 remote system; the ``load'' command will download a program into the
1888 remote system. Serial stubs for the m68k and i386 are provided. Gdb
1889 also supports debugging of realtime processes running under VxWorks,
1890 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
1891 stub on the target system.
1893 New CPUs supported include the AMD 29000 and Intel 960.
1895 GDB now reads object files and symbol tables via a ``binary file''
1896 library, which allows a single copy of GDB to debug programs of multiple
1897 object file types such as a.out and coff.
1899 There is now a GDB reference card in "doc/refcard.tex". (Make targets
1900 refcard.dvi and refcard.ps are available to format it).
1903 * Control-Variable user interface simplified
1905 All variables that control the operation of the debugger can be set
1906 by the ``set'' command, and displayed by the ``show'' command.
1908 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
1909 ``Show prompt'' produces the response:
1910 Gdb's prompt is new-gdb=>.
1912 What follows are the NEW set commands. The command ``help set'' will
1913 print a complete list of old and new set commands. ``help set FOO''
1914 will give a longer description of the variable FOO. ``show'' will show
1915 all of the variable descriptions and their current settings.
1917 confirm on/off: Enables warning questions for operations that are
1918 hard to recover from, e.g. rerunning the program while
1919 it is already running. Default is ON.
1921 editing on/off: Enables EMACS style command line editing
1922 of input. Previous lines can be recalled with
1923 control-P, the current line can be edited with control-B,
1924 you can search for commands with control-R, etc.
1927 history filename NAME: NAME is where the gdb command history
1928 will be stored. The default is .gdb_history,
1929 or the value of the environment variable
1932 history size N: The size, in commands, of the command history. The
1933 default is 256, or the value of the environment variable
1936 history save on/off: If this value is set to ON, the history file will
1937 be saved after exiting gdb. If set to OFF, the
1938 file will not be saved. The default is OFF.
1940 history expansion on/off: If this value is set to ON, then csh-like
1941 history expansion will be performed on
1942 command line input. The default is OFF.
1944 radix N: Sets the default radix for input and output. It can be set
1945 to 8, 10, or 16. Note that the argument to "radix" is interpreted
1946 in the current radix, so "set radix 10" is always a no-op.
1948 height N: This integer value is the number of lines on a page. Default
1949 is 24, the current `stty rows'' setting, or the ``li#''
1950 setting from the termcap entry matching the environment
1953 width N: This integer value is the number of characters on a line.
1954 Default is 80, the current `stty cols'' setting, or the ``co#''
1955 setting from the termcap entry matching the environment
1958 Note: ``set screensize'' is obsolete. Use ``set height'' and
1959 ``set width'' instead.
1961 print address on/off: Print memory addresses in various command displays,
1962 such as stack traces and structure values. Gdb looks
1963 more ``symbolic'' if you turn this off; it looks more
1964 ``machine level'' with it on. Default is ON.
1966 print array on/off: Prettyprint arrays. New convenient format! Default
1969 print demangle on/off: Print C++ symbols in "source" form if on,
1972 print asm-demangle on/off: Same, for assembler level printouts
1975 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
1978 * Support for Epoch Environment.
1980 The epoch environment is a version of Emacs v18 with windowing. One
1981 new command, ``inspect'', is identical to ``print'', except that if you
1982 are running in the epoch environment, the value is printed in its own
1986 * Support for Shared Libraries
1988 GDB can now debug programs and core files that use SunOS shared libraries.
1989 Symbols from a shared library cannot be referenced
1990 before the shared library has been linked with the program (this
1991 happens after you type ``run'' and before the function main() is entered).
1992 At any time after this linking (including when examining core files
1993 from dynamically linked programs), gdb reads the symbols from each
1994 shared library when you type the ``sharedlibrary'' command.
1995 It can be abbreviated ``share''.
1997 sharedlibrary REGEXP: Load shared object library symbols for files
1998 matching a unix regular expression. No argument
1999 indicates to load symbols for all shared libraries.
2001 info sharedlibrary: Status of loaded shared libraries.
2006 A watchpoint stops execution of a program whenever the value of an
2007 expression changes. Checking for this slows down execution
2008 tremendously whenever you are in the scope of the expression, but is
2009 quite useful for catching tough ``bit-spreader'' or pointer misuse
2010 problems. Some machines such as the 386 have hardware for doing this
2011 more quickly, and future versions of gdb will use this hardware.
2013 watch EXP: Set a watchpoint (breakpoint) for an expression.
2015 info watchpoints: Information about your watchpoints.
2017 delete N: Deletes watchpoint number N (same as breakpoints).
2018 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
2019 enable N: Re-enables watchpoint number N (same as breakpoints).
2022 * C++ multiple inheritance
2024 When used with a GCC version 2 compiler, GDB supports multiple inheritance
2027 * C++ exception handling
2029 Gdb now supports limited C++ exception handling. Besides the existing
2030 ability to breakpoint on an exception handler, gdb can breakpoint on
2031 the raising of an exception (before the stack is peeled back to the
2034 catch FOO: If there is a FOO exception handler in the dynamic scope,
2035 set a breakpoint to catch exceptions which may be raised there.
2036 Multiple exceptions (``catch foo bar baz'') may be caught.
2038 info catch: Lists all exceptions which may be caught in the
2039 current stack frame.
2042 * Minor command changes
2044 The command ``call func (arg, arg, ...)'' now acts like the print
2045 command, except it does not print or save a value if the function's result
2046 is void. This is similar to dbx usage.
2048 The ``up'' and ``down'' commands now always print the frame they end up
2049 at; ``up-silently'' and `down-silently'' can be used in scripts to change
2050 frames without printing.
2052 * New directory command
2054 'dir' now adds directories to the FRONT of the source search path.
2055 The path starts off empty. Source files that contain debug information
2056 about the directory in which they were compiled can be found even
2057 with an empty path; Sun CC and GCC include this information. If GDB can't
2058 find your source file in the current directory, type "dir .".
2060 * Configuring GDB for compilation
2062 For normal use, type ``./configure host''. See README or gdb.texinfo
2065 GDB now handles cross debugging. If you are remotely debugging between
2066 two different machines, type ``./configure host -target=targ''.
2067 Host is the machine where GDB will run; targ is the machine
2068 where the program that you are debugging will run.