1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 5.2:
6 * ``gdbserver'' now supports multithreaded applications on some targets
8 Support for multithreaded applications using LinuxThreads has been added
9 for arm*-*-linux*, i[3456]86-*-linux*, mips*-*-linux*, powerpc*-*-linux*,
12 * GDB now supports C/C++ preprocessor macros.
14 GDB now expands preprocessor macro invocations in C/C++ expressions,
15 and provides various commands for showing macro definitions and how
18 Most compilers don't include information about macros in the debugging
19 information by default. In GCC 3.1, for example, you need to compile
20 your program with the options `-gdwarf-2 -g3'. If the macro
21 information is present in the executable, GDB will read it.
23 Here are the new commands for working with macros:
25 ** macro expand EXPRESSION
27 Expand any macro invocations in expression, and show the result.
29 ** show macro MACRO-NAME
31 Show the definition of the macro named MACRO-NAME, and where it was
34 * Multi-arched targets.
36 DEC Alpha (partial) alpha*-*-*
37 DEC VAX (partial) vax-*-*
39 National Semiconductor NS32000 (partial) ns32k-*-*
40 Motorola 68000 (partial) m68k-*-*
41 Motorola MCORE mcore-*-*
46 Fujitsu FRV architecture added by Red Hat frv*-*-*
49 * New native configurations
51 Alpha NetBSD alpha*-*-netbsd*
52 SH NetBSD sh*-*-netbsdelf*
53 MIPS NetBSD mips*-*-netbsd*
54 UltraSPARC NetBSD sparc64-*-netbsd*
56 * OBSOLETE configurations and files
58 Configurations that have been declared obsolete in this release have
59 been commented out. Unless there is activity to revive these
60 configurations, the next release of GDB will have their sources
63 * REMOVED configurations and files
65 AMD 29k family via UDI a29k-amd-udi, udi29k
66 A29K VxWorks a29k-*-vxworks
67 AMD 29000 embedded, using EBMON a29k-none-none
68 AMD 29000 embedded with COFF a29k-none-coff
69 AMD 29000 embedded with a.out a29k-none-aout
71 testsuite/gdb.hp/gdb.threads-hp/ directory
73 * New command "set max-user-call-depth <nnn>"
75 This command allows the user to limit the call depth of user-defined
76 commands. The default is 1024.
78 * Changes in FreeBSD/i386 native debugging.
80 Support for the "generate-core-file" has been added.
82 * New commands "dump", "append", and "restore".
84 These commands allow data to be copied from target memory
85 to a bfd-format or binary file (dump and append), and back
86 from a file into memory (restore).
88 *** Changes in GDB 5.2:
90 * New command "set trust-readonly-sections on[off]".
92 This command is a hint that tells gdb that read-only sections
93 really are read-only (ie. that their contents will not change).
94 In this mode, gdb will go to the object file rather than the
95 target to read memory from read-only sections (such as ".text").
96 This can be a significant performance improvement on some
97 (notably embedded) targets.
99 * New command "generate-core-file" (or "gcore").
101 This new gdb command allows the user to drop a core file of the child
102 process state at any time. So far it's been implemented only for
103 GNU/Linux and Solaris, but should be relatively easily ported to other
104 hosts. Argument is core file name (defaults to core.<pid>).
106 * New command line option
108 GDB now accepts --pid or -p followed by a process id.
110 * Change in command line behavior -- corefiles vs. process ids.
112 There is a subtle behavior in the way in which GDB handles
113 command line arguments. The first non-flag argument is always
114 a program to debug, but the second non-flag argument may either
115 be a corefile or a process id. Previously, GDB would attempt to
116 open the second argument as a corefile, and if that failed, would
117 issue a superfluous error message and then attempt to attach it as
118 a process. Now, if the second argument begins with a non-digit,
119 it will be treated as a corefile. If it begins with a digit,
120 GDB will attempt to attach it as a process, and if no such process
121 is found, will then attempt to open it as a corefile.
123 * Changes in ARM configurations.
125 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
126 configuration is fully multi-arch.
128 * New native configurations
130 ARM NetBSD arm*-*-netbsd*
131 x86 OpenBSD i[3456]86-*-openbsd*
132 AMD x86-64 running GNU/Linux x86_64-*-linux-*
133 Sparc64 running FreeBSD sparc64-*-freebsd*
137 Sanyo XStormy16 xstormy16-elf
139 * OBSOLETE configurations and files
141 Configurations that have been declared obsolete in this release have
142 been commented out. Unless there is activity to revive these
143 configurations, the next release of GDB will have their sources
146 AMD 29k family via UDI a29k-amd-udi, udi29k
147 A29K VxWorks a29k-*-vxworks
148 AMD 29000 embedded, using EBMON a29k-none-none
149 AMD 29000 embedded with COFF a29k-none-coff
150 AMD 29000 embedded with a.out a29k-none-aout
152 testsuite/gdb.hp/gdb.threads-hp/ directory
154 * REMOVED configurations and files
156 TI TMS320C80 tic80-*-*
158 PowerPC Solaris powerpcle-*-solaris*
159 PowerPC Windows NT powerpcle-*-cygwin32
160 PowerPC Netware powerpc-*-netware*
161 Harris/CXUX m88k m88*-harris-cxux*
162 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
163 ns32k-utek-sysv* ns32k-utek-*
164 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
165 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
166 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
167 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
168 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
170 * Changes to command line processing
172 The new `--args' feature can be used to specify command-line arguments
173 for the inferior from gdb's command line.
175 * Changes to key bindings
177 There is a new `operate-and-get-next' function bound to `C-o'.
179 *** Changes in GDB 5.1.1
181 Fix compile problem on DJGPP.
183 Fix a problem with floating-point registers on the i386 being
186 Fix to stop GDB crashing on .debug_str debug info.
188 Numerous documentation fixes.
190 Numerous testsuite fixes.
192 *** Changes in GDB 5.1:
194 * New native configurations
196 Alpha FreeBSD alpha*-*-freebsd*
197 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
198 MIPS GNU/Linux mips*-*-linux*
199 MIPS SGI Irix 6.x mips*-sgi-irix6*
201 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
205 Motorola 68HC11 and 68HC12 m68hc11-elf
207 UltraSparc running GNU/Linux sparc64-*-linux*
209 * OBSOLETE configurations and files
211 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
212 Harris/CXUX m88k m88*-harris-cxux*
213 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
214 ns32k-utek-sysv* ns32k-utek-*
215 TI TMS320C80 tic80-*-*
217 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
218 PowerPC Solaris powerpcle-*-solaris*
219 PowerPC Windows NT powerpcle-*-cygwin32
220 PowerPC Netware powerpc-*-netware*
221 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
222 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
223 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
224 Apple Macintosh (MPW) host N/A
226 stuff.c (Program to stuff files into a specially prepared space in kdb)
227 kdb-start.c (Main loop for the standalone kernel debugger)
229 Configurations that have been declared obsolete in this release have
230 been commented out. Unless there is activity to revive these
231 configurations, the next release of GDB will have their sources
234 * REMOVED configurations and files
236 Altos 3068 m68*-altos-*
237 Convex c1-*-*, c2-*-*
239 ARM RISCix arm-*-* (as host)
243 * GDB has been converted to ISO C.
245 GDB's source code has been converted to ISO C. In particular, the
246 sources are fully protoized, and rely on standard headers being
251 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
253 * The MI enabled by default.
255 The new machine oriented interface (MI) introduced in GDB 5.0 has been
256 revised and enabled by default. Packages which use GDB as a debugging
257 engine behind a UI or another front end are encouraged to switch to
258 using the GDB/MI interface, instead of the old annotations interface
259 which is now deprecated.
261 * Support for debugging Pascal programs.
263 GDB now includes support for debugging Pascal programs. The following
264 main features are supported:
266 - Pascal-specific data types such as sets;
268 - automatic recognition of Pascal sources based on file-name
271 - Pascal-style display of data types, variables, and functions;
273 - a Pascal expression parser.
275 However, some important features are not yet supported.
277 - Pascal string operations are not supported at all;
279 - there are some problems with boolean types;
281 - Pascal type hexadecimal constants are not supported
282 because they conflict with the internal variables format;
284 - support for Pascal objects and classes is not full yet;
286 - unlike Pascal, GDB is case-sensitive for symbol names.
288 * Changes in completion.
290 Commands such as `shell', `run' and `set args', which pass arguments
291 to inferior programs, now complete on file names, similar to what
292 users expect at the shell prompt.
294 Commands which accept locations, such as `disassemble', `print',
295 `breakpoint', `until', etc. now complete on filenames as well as
296 program symbols. Thus, if you type "break foob TAB", and the source
297 files linked into the programs include `foobar.c', that file name will
298 be one of the candidates for completion. However, file names are not
299 considered for completion after you typed a colon that delimits a file
300 name from a name of a function in that file, as in "break foo.c:bar".
302 `set demangle-style' completes on available demangling styles.
304 * New platform-independent commands:
306 It is now possible to define a post-hook for a command as well as a
307 hook that runs before the command. For more details, see the
308 documentation of `hookpost' in the GDB manual.
310 * Changes in GNU/Linux native debugging.
312 Support for debugging multi-threaded programs has been completely
313 revised for all platforms except m68k and sparc. You can now debug as
314 many threads as your system allows you to have.
316 Attach/detach is supported for multi-threaded programs.
318 Support for SSE registers was added for x86. This doesn't work for
319 multi-threaded programs though.
321 * Changes in MIPS configurations.
323 Multi-arch support is enabled for all MIPS configurations.
325 GDB can now be built as native debugger on SGI Irix 6.x systems for
326 debugging n32 executables. (Debugging 64-bit executables is not yet
329 * Unified support for hardware watchpoints in all x86 configurations.
331 Most (if not all) native x86 configurations support hardware-assisted
332 breakpoints and watchpoints in a unified manner. This support
333 implements debug register sharing between watchpoints, which allows to
334 put a virtually infinite number of watchpoints on the same address,
335 and also supports watching regions up to 16 bytes with several debug
338 The new maintenance command `maintenance show-debug-regs' toggles
339 debugging print-outs in functions that insert, remove, and test
340 watchpoints and hardware breakpoints.
342 * Changes in the DJGPP native configuration.
344 New command ``info dos sysinfo'' displays assorted information about
345 the CPU, OS, memory, and DPMI server.
347 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
348 display information about segment descriptors stored in GDT, LDT, and
351 New commands ``info dos pde'' and ``info dos pte'' display entries
352 from Page Directory and Page Tables (for now works with CWSDPMI only).
353 New command ``info dos address-pte'' displays the Page Table entry for
354 a given linear address.
356 GDB can now pass command lines longer than 126 characters to the
357 program being debugged (requires an update to the libdbg.a library
358 which is part of the DJGPP development kit).
360 DWARF2 debug info is now supported.
362 It is now possible to `step' and `next' through calls to `longjmp'.
364 * Changes in documentation.
366 All GDB documentation was converted to GFDL, the GNU Free
367 Documentation License.
369 Tracepoints-related commands are now fully documented in the GDB
372 TUI, the Text-mode User Interface, is now documented in the manual.
374 Tracepoints-related commands are now fully documented in the GDB
377 The "GDB Internals" manual now has an index. It also includes
378 documentation of `ui_out' functions, GDB coding standards, x86
379 hardware watchpoints, and memory region attributes.
381 * GDB's version number moved to ``version.in''
383 The Makefile variable VERSION has been replaced by the file
384 ``version.in''. People creating GDB distributions should update the
385 contents of this file.
389 GUD support is now a standard part of the EMACS distribution.
391 *** Changes in GDB 5.0:
393 * Improved support for debugging FP programs on x86 targets
395 Unified and much-improved support for debugging floating-point
396 programs on all x86 targets. In particular, ``info float'' now
397 displays the FP registers in the same format on all x86 targets, with
398 greater level of detail.
400 * Improvements and bugfixes in hardware-assisted watchpoints
402 It is now possible to watch array elements, struct members, and
403 bitfields with hardware-assisted watchpoints. Data-read watchpoints
404 on x86 targets no longer erroneously trigger when the address is
407 * Improvements in the native DJGPP version of GDB
409 The distribution now includes all the scripts and auxiliary files
410 necessary to build the native DJGPP version on MS-DOS/MS-Windows
411 machines ``out of the box''.
413 The DJGPP version can now debug programs that use signals. It is
414 possible to catch signals that happened in the debuggee, deliver
415 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
416 would kill the program being debugged.) Programs that hook hardware
417 interrupts (keyboard, timer, etc.) can also be debugged.
419 It is now possible to debug DJGPP programs that redirect their
420 standard handles or switch them to raw (as opposed to cooked) mode, or
421 even close them. The command ``run < foo > bar'' works as expected,
422 and ``info terminal'' reports useful information about the debuggee's
423 terminal, including raw/cooked mode, redirection, etc.
425 The DJGPP version now uses termios functions for console I/O, which
426 enables debugging graphics programs. Interrupting GDB with Ctrl-C
429 DOS-style file names with drive letters are now fully supported by
432 It is now possible to debug DJGPP programs that switch their working
433 directory. It is also possible to rerun the debuggee any number of
434 times without restarting GDB; thus, you can use the same setup,
435 breakpoints, etc. for many debugging sessions.
437 * New native configurations
439 ARM GNU/Linux arm*-*-linux*
440 PowerPC GNU/Linux powerpc-*-linux*
444 Motorola MCore mcore-*-*
445 x86 VxWorks i[3456]86-*-vxworks*
446 PowerPC VxWorks powerpc-*-vxworks*
447 TI TMS320C80 tic80-*-*
449 * OBSOLETE configurations
451 Altos 3068 m68*-altos-*
452 Convex c1-*-*, c2-*-*
454 ARM RISCix arm-*-* (as host)
457 Configurations that have been declared obsolete will be commented out,
458 but the code will be left in place. If there is no activity to revive
459 these configurations before the next release of GDB, the sources will
460 be permanently REMOVED.
462 * Gould support removed
464 Support for the Gould PowerNode and NP1 has been removed.
466 * New features for SVR4
468 On SVR4 native platforms (such as Solaris), if you attach to a process
469 without first loading a symbol file, GDB will now attempt to locate and
470 load symbols from the running process's executable file.
472 * Many C++ enhancements
474 C++ support has been greatly improved. Overload resolution now works properly
475 in almost all cases. RTTI support is on the way.
477 * Remote targets can connect to a sub-program
479 A popen(3) style serial-device has been added. This device starts a
480 sub-process (such as a stand-alone simulator) and then communicates
481 with that. The sub-program to run is specified using the syntax
482 ``|<program> <args>'' vis:
484 (gdb) set remotedebug 1
485 (gdb) target extended-remote |mn10300-elf-sim program-args
487 * MIPS 64 remote protocol
489 A long standing bug in the mips64 remote protocol where by GDB
490 expected certain 32 bit registers (ex SR) to be transfered as 32
491 instead of 64 bits has been fixed.
493 The command ``set remote-mips64-transfers-32bit-regs on'' has been
494 added to provide backward compatibility with older versions of GDB.
496 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
498 The command ``set remotebinarydownload'' command has been replaced by
499 ``set remote X-packet''. Other commands in ``set remote'' family
500 include ``set remote P-packet''.
502 * Breakpoint commands accept ranges.
504 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
505 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
506 ``tracepoint passcount'' also accepts a range of tracepoints.
508 * ``apropos'' command added.
510 The ``apropos'' command searches through command names and
511 documentation strings, printing out matches, making it much easier to
512 try to find a command that does what you are looking for.
516 A new machine oriented interface (MI) has been added to GDB. This
517 interface is designed for debug environments running GDB as a separate
518 process. This is part of the long term libGDB project. See the
519 "GDB/MI" chapter of the GDB manual for further information. It can be
520 enabled by configuring with:
522 .../configure --enable-gdbmi
524 *** Changes in GDB-4.18:
526 * New native configurations
528 HP-UX 10.20 hppa*-*-hpux10.20
529 HP-UX 11.x hppa*-*-hpux11.0*
530 M68K GNU/Linux m68*-*-linux*
534 Fujitsu FR30 fr30-*-elf*
535 Intel StrongARM strongarm-*-*
536 Mitsubishi D30V d30v-*-*
538 * OBSOLETE configurations
540 Gould PowerNode, NP1 np1-*-*, pn-*-*
542 Configurations that have been declared obsolete will be commented out,
543 but the code will be left in place. If there is no activity to revive
544 these configurations before the next release of GDB, the sources will
545 be permanently REMOVED.
549 As a compatibility experiment, GDB's source files buildsym.h and
550 buildsym.c have been converted to pure standard C, no longer
551 containing any K&R compatibility code. We believe that all systems in
552 use today either come with a standard C compiler, or have a GCC port
553 available. If this is not true, please report the affected
554 configuration to bug-gdb@gnu.org immediately. See the README file for
555 information about getting a standard C compiler if you don't have one
560 GDB now uses readline 2.2.
562 * set extension-language
564 You can now control the mapping between filename extensions and source
565 languages by using the `set extension-language' command. For instance,
566 you can ask GDB to treat .c files as C++ by saying
567 set extension-language .c c++
568 The command `info extensions' lists all of the recognized extensions
569 and their associated languages.
571 * Setting processor type for PowerPC and RS/6000
573 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
574 you can use the `set processor' command to specify what variant of the
575 PowerPC family you are debugging. The command
579 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
580 following PowerPC and RS6000 variants:
582 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
583 rs6000 IBM RS6000 ("POWER") architecture, user-level view
585 403GC IBM PowerPC 403GC
586 505 Motorola PowerPC 505
587 860 Motorola PowerPC 860 or 850
588 601 Motorola PowerPC 601
589 602 Motorola PowerPC 602
590 603 Motorola/IBM PowerPC 603 or 603e
591 604 Motorola PowerPC 604 or 604e
592 750 Motorola/IBM PowerPC 750 or 750
594 At the moment, this command just tells GDB what to name the
595 special-purpose processor registers. Since almost all the affected
596 registers are inaccessible to user-level programs, this command is
597 only useful for remote debugging in its present form.
601 Thanks to a major code donation from Hewlett-Packard, GDB now has much
602 more extensive support for HP-UX. Added features include shared
603 library support, kernel threads and hardware watchpoints for 11.00,
604 support for HP's ANSI C and C++ compilers, and a compatibility mode
605 for xdb and dbx commands.
609 HP's donation includes the new concept of catchpoints, which is a
610 generalization of the old catch command. On HP-UX, it is now possible
611 to catch exec, fork, and vfork, as well as library loading.
613 This means that the existing catch command has changed; its first
614 argument now specifies the type of catch to be set up. See the
615 output of "help catch" for a list of catchpoint types.
617 * Debugging across forks
619 On HP-UX, you can choose which process to debug when a fork() happens
624 HP has donated a curses-based terminal user interface (TUI). To get
625 it, build with --enable-tui. Although this can be enabled for any
626 configuration, at present it only works for native HP debugging.
628 * GDB remote protocol additions
630 A new protocol packet 'X' that writes binary data is now available.
631 Default behavior is to try 'X', then drop back to 'M' if the stub
632 fails to respond. The settable variable `remotebinarydownload'
633 allows explicit control over the use of 'X'.
635 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
636 full 64-bit address. The command
638 set remoteaddresssize 32
640 can be used to revert to the old behaviour. For existing remote stubs
641 the change should not be noticed, as the additional address information
644 In order to assist in debugging stubs, you may use the maintenance
645 command `packet' to send any text string to the stub. For instance,
647 maint packet heythere
649 sends the packet "$heythere#<checksum>". Note that it is very easy to
650 disrupt a debugging session by sending the wrong packet at the wrong
653 The compare-sections command allows you to compare section data on the
654 target to what is in the executable file without uploading or
655 downloading, by comparing CRC checksums.
657 * Tracing can collect general expressions
659 You may now collect general expressions at tracepoints. This requires
660 further additions to the target-side stub; see tracepoint.c and
661 doc/agentexpr.texi for further details.
663 * mask-address variable for Mips
665 For Mips targets, you may control the zeroing of the upper 32 bits of
666 a 64-bit address by entering `set mask-address on'. This is mainly
667 of interest to users of embedded R4xxx and R5xxx processors.
669 * Higher serial baud rates
671 GDB's serial code now allows you to specify baud rates 57600, 115200,
672 230400, and 460800 baud. (Note that your host system may not be able
673 to achieve all of these rates.)
677 The i960 configuration now includes an initial implementation of a
678 builtin simulator, contributed by Jim Wilson.
681 *** Changes in GDB-4.17:
683 * New native configurations
685 Alpha GNU/Linux alpha*-*-linux*
686 Unixware 2.x i[3456]86-unixware2*
687 Irix 6.x mips*-sgi-irix6*
688 PowerPC GNU/Linux powerpc-*-linux*
689 PowerPC Solaris powerpcle-*-solaris*
690 Sparc GNU/Linux sparc-*-linux*
691 Motorola sysV68 R3V7.1 m68k-motorola-sysv
695 Argonaut Risc Chip (ARC) arc-*-*
696 Hitachi H8/300S h8300*-*-*
697 Matsushita MN10200 w/simulator mn10200-*-*
698 Matsushita MN10300 w/simulator mn10300-*-*
699 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
700 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
701 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
702 Mitsubishi D10V w/simulator d10v-*-*
703 Mitsubishi M32R/D w/simulator m32r-*-elf*
704 Tsqware Sparclet sparclet-*-*
705 NEC V850 w/simulator v850-*-*
707 * New debugging protocols
709 ARM with RDI protocol arm*-*-*
710 M68K with dBUG monitor m68*-*-{aout,coff,elf}
711 DDB and LSI variants of PMON protocol mips*-*-*
712 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
713 PowerPC with SDS protocol powerpc{,le}-*-eabi
714 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
718 All configurations can now understand and use the DWARF 2 debugging
719 format. The choice is automatic, if the symbol file contains DWARF 2
724 GDB now includes basic Java language support. This support is
725 only useful with Java compilers that produce native machine code.
727 * solib-absolute-prefix and solib-search-path
729 For SunOS and SVR4 shared libraries, you may now set the prefix for
730 loading absolute shared library symbol files, and the search path for
731 locating non-absolute shared library symbol files.
733 * Live range splitting
735 GDB can now effectively debug code for which GCC has performed live
736 range splitting as part of its optimization. See gdb/doc/LRS for
737 more details on the expected format of the stabs information.
741 GDB's support for the GNU Hurd, including thread debugging, has been
742 updated to work with current versions of the Hurd.
746 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
747 instruction set. ARM GDB automatically detects when Thumb
748 instructions are in use, and adjusts disassembly and backtracing
753 GDB's MIPS target configurations now handle the MIP16 16-bit
758 GDB now includes support for overlays; if an executable has been
759 linked such that multiple sections are based at the same address, GDB
760 will decide which section to use for symbolic info. You can choose to
761 control the decision manually, using overlay commands, or implement
762 additional target-side support and use "overlay load-target" to bring
763 in the overlay mapping. Do "help overlay" for more detail.
767 The command "info symbol <address>" displays information about
768 the symbol at the specified address.
772 The standard remote protocol now includes an extension that allows
773 asynchronous collection and display of trace data. This requires
774 extensive support in the target-side debugging stub. Tracing mode
775 includes a new interaction mode in GDB and new commands: see the
776 file tracepoint.c for more details.
780 Configurations for embedded MIPS now include a simulator contributed
781 by Cygnus Solutions. The simulator supports the instruction sets
782 of most MIPS variants.
786 Sparc configurations may now include the ERC32 simulator contributed
787 by the European Space Agency. The simulator is not built into
788 Sparc targets by default; configure with --enable-sim to include it.
792 For target configurations that may include multiple variants of a
793 basic architecture (such as MIPS and SH), you may now set the
794 architecture explicitly. "set arch" sets, "info arch" lists
795 the possible architectures.
797 *** Changes in GDB-4.16:
799 * New native configurations
801 Windows 95, x86 Windows NT i[345]86-*-cygwin32
802 M68K NetBSD m68k-*-netbsd*
803 PowerPC AIX 4.x powerpc-*-aix*
804 PowerPC MacOS powerpc-*-macos*
805 PowerPC Windows NT powerpcle-*-cygwin32
806 RS/6000 AIX 4.x rs6000-*-aix4*
810 ARM with RDP protocol arm-*-*
811 I960 with MON960 i960-*-coff
812 MIPS VxWorks mips*-*-vxworks*
813 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
814 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
816 Matra Sparclet sparclet-*-*
820 The powerpc-eabi configuration now includes the PSIM simulator,
821 contributed by Andrew Cagney, with assistance from Mike Meissner.
822 PSIM is a very elaborate model of the PowerPC, including not only
823 basic instruction set execution, but also details of execution unit
824 performance and I/O hardware. See sim/ppc/README for more details.
828 GDB now works with Solaris 2.5.
830 * Windows 95/NT native
832 GDB will now work as a native debugger on Windows 95 and Windows NT.
833 To build it from source, you must use the "gnu-win32" environment,
834 which uses a DLL to emulate enough of Unix to run the GNU tools.
835 Further information, binaries, and sources are available at
836 ftp.cygnus.com, under pub/gnu-win32.
838 * dont-repeat command
840 If a user-defined command includes the command `dont-repeat', then the
841 command will not be repeated if the user just types return. This is
842 useful if the command is time-consuming to run, so that accidental
843 extra keystrokes don't run the same command many times.
845 * Send break instead of ^C
847 The standard remote protocol now includes an option to send a break
848 rather than a ^C to the target in order to interrupt it. By default,
849 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
851 * Remote protocol timeout
853 The standard remote protocol includes a new variable `remotetimeout'
854 that allows you to set the number of seconds before GDB gives up trying
855 to read from the target. The default value is 2.
857 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
859 By default GDB will automatically keep track of objects as they are
860 loaded and unloaded by the dynamic linker. By using the command `set
861 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
862 when shared library events occur, thus allowing you to set breakpoints
863 in shared libraries which are explicitly loaded by the inferior.
865 Note this feature does not work on hpux8. On hpux9 you must link
866 /usr/lib/end.o into your program. This feature should work
867 automatically on hpux10.
869 * Irix 5.x hardware watchpoint support
871 Irix 5 configurations now support the use of hardware watchpoints.
873 * Mips protocol "SYN garbage limit"
875 When debugging a Mips target using the `target mips' protocol, you
876 may set the number of characters that GDB will ignore by setting
877 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
878 every character. The default value is 1050.
880 * Recording and replaying remote debug sessions
882 If you set `remotelogfile' to the name of a file, gdb will write to it
883 a recording of a remote debug session. This recording may then be
884 replayed back to gdb using "gdbreplay". See gdbserver/README for
885 details. This is useful when you have a problem with GDB while doing
886 remote debugging; you can make a recording of the session and send it
887 to someone else, who can then recreate the problem.
889 * Speedups for remote debugging
891 GDB includes speedups for downloading and stepping MIPS systems using
892 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
893 and more efficient S-record downloading.
895 * Memory use reductions and statistics collection
897 GDB now uses less memory and reports statistics about memory usage.
898 Try the `maint print statistics' command, for example.
900 *** Changes in GDB-4.15:
904 The symbol reader for AIX GDB now uses partial symbol tables. This
905 can greatly improve startup time, especially for large executables.
907 * Remote targets use caching
909 Remote targets now use a data cache to speed up communication with the
910 remote side. The data cache could lead to incorrect results because
911 it doesn't know about volatile variables, thus making it impossible to
912 debug targets which use memory mapped I/O devices. `set remotecache
913 off' turns the the data cache off.
915 * Remote targets may have threads
917 The standard remote protocol now includes support for multiple threads
918 in the target system, using new protocol commands 'H' and 'T'. See
919 gdb/remote.c for details.
923 If GDB is configured with `--enable-netrom', then it will include
924 support for the NetROM ROM emulator from XLNT Designs. The NetROM
925 acts as though it is a bank of ROM on the target board, but you can
926 write into it over the network. GDB's support consists only of
927 support for fast loading into the emulated ROM; to debug, you must use
928 another protocol, such as standard remote protocol. The usual
929 sequence is something like
931 target nrom <netrom-hostname>
933 target remote <netrom-hostname>:1235
937 GDB now includes support for the Apple Macintosh, as a host only. It
938 may be run as either an MPW tool or as a standalone application, and
939 it can debug through the serial port. All the usual GDB commands are
940 available, but to the target command, you must supply "serial" as the
941 device type instead of "/dev/ttyXX". See mpw-README in the main
942 directory for more information on how to build. The MPW configuration
943 scripts */mpw-config.in support only a few targets, and only the
944 mips-idt-ecoff target has been tested.
948 GDB configuration now uses autoconf. This is not user-visible,
949 but does simplify configuration and building.
953 GDB now supports hpux10.
955 *** Changes in GDB-4.14:
957 * New native configurations
959 x86 FreeBSD i[345]86-*-freebsd
960 x86 NetBSD i[345]86-*-netbsd
961 NS32k NetBSD ns32k-*-netbsd
962 Sparc NetBSD sparc-*-netbsd
966 A29K VxWorks a29k-*-vxworks
967 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
968 CPU32 EST-300 emulator m68*-*-est*
969 PowerPC ELF powerpc-*-elf
972 * Alpha OSF/1 support for procfs
974 GDB now supports procfs under OSF/1-2.x and higher, which makes it
975 possible to attach to running processes. As the mounting of the /proc
976 filesystem is optional on the Alpha, GDB automatically determines
977 the availability of /proc during startup. This can lead to problems
978 if /proc is unmounted after GDB has been started.
980 * Arguments to user-defined commands
982 User commands may accept up to 10 arguments separated by whitespace.
983 Arguments are accessed within the user command via $arg0..$arg9. A
986 print $arg0 + $arg1 + $arg2
988 To execute the command use:
991 Defines the command "adder" which prints the sum of its three arguments.
992 Note the arguments are text substitutions, so they may reference variables,
993 use complex expressions, or even perform inferior function calls.
995 * New `if' and `while' commands
997 This makes it possible to write more sophisticated user-defined
998 commands. Both commands take a single argument, which is the
999 expression to evaluate, and must be followed by the commands to
1000 execute, one per line, if the expression is nonzero, the list being
1001 terminated by the word `end'. The `if' command list may include an
1002 `else' word, which causes the following commands to be executed only
1003 if the expression is zero.
1005 * Fortran source language mode
1007 GDB now includes partial support for Fortran 77. It will recognize
1008 Fortran programs and can evaluate a subset of Fortran expressions, but
1009 variables and functions may not be handled correctly. GDB will work
1010 with G77, but does not yet know much about symbols emitted by other
1013 * Better HPUX support
1015 Most debugging facilities now work on dynamic executables for HPPAs
1016 running hpux9 or later. You can attach to running dynamically linked
1017 processes, but by default the dynamic libraries will be read-only, so
1018 for instance you won't be able to put breakpoints in them. To change
1019 that behavior do the following before running the program:
1025 This will cause the libraries to be mapped private and read-write.
1026 To revert to the normal behavior, do this:
1032 You cannot set breakpoints or examine data in the library until after
1033 the library is loaded if the function/data symbols do not have
1036 GDB can now also read debug symbols produced by the HP C compiler on
1037 HPPAs (sorry, no C++, Fortran or 68k support).
1039 * Target byte order now dynamically selectable
1041 You can choose which byte order to use with a target system, via the
1042 commands "set endian big" and "set endian little", and you can see the
1043 current setting by using "show endian". You can also give the command
1044 "set endian auto", in which case GDB will use the byte order
1045 associated with the executable. Currently, only embedded MIPS
1046 configurations support dynamic selection of target byte order.
1048 * New DOS host serial code
1050 This version uses DPMI interrupts to handle buffered I/O, so you
1051 no longer need to run asynctsr when debugging boards connected to
1054 *** Changes in GDB-4.13:
1056 * New "complete" command
1058 This lists all the possible completions for the rest of the line, if it
1059 were to be given as a command itself. This is intended for use by emacs.
1061 * Trailing space optional in prompt
1063 "set prompt" no longer adds a space for you after the prompt you set. This
1064 allows you to set a prompt which ends in a space or one that does not.
1066 * Breakpoint hit counts
1068 "info break" now displays a count of the number of times the breakpoint
1069 has been hit. This is especially useful in conjunction with "ignore"; you
1070 can ignore a large number of breakpoint hits, look at the breakpoint info
1071 to see how many times the breakpoint was hit, then run again, ignoring one
1072 less than that number, and this will get you quickly to the last hit of
1075 * Ability to stop printing at NULL character
1077 "set print null-stop" will cause GDB to stop printing the characters of
1078 an array when the first NULL is encountered. This is useful when large
1079 arrays actually contain only short strings.
1081 * Shared library breakpoints
1083 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
1084 breakpoints in shared libraries before the executable is run.
1086 * Hardware watchpoints
1088 There is a new hardware breakpoint for the watch command for sparclite
1089 targets. See gdb/sparclite/hw_breakpoint.note.
1091 Hardware watchpoints are also now supported under GNU/Linux.
1095 Annotations have been added. These are for use with graphical interfaces,
1096 and are still experimental. Currently only gdba.el uses these.
1098 * Improved Irix 5 support
1100 GDB now works properly with Irix 5.2.
1102 * Improved HPPA support
1104 GDB now works properly with the latest GCC and GAS.
1106 * New native configurations
1108 Sequent PTX4 i[34]86-sequent-ptx4
1109 HPPA running OSF/1 hppa*-*-osf*
1110 Atari TT running SVR4 m68*-*-sysv4*
1111 RS/6000 LynxOS rs6000-*-lynxos*
1115 OS/9000 i[34]86-*-os9k
1116 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
1119 * Hitachi SH7000 and E7000-PC ICE support
1121 There is now support for communicating with the Hitachi E7000-PC ICE.
1122 This is available automatically when GDB is configured for the SH.
1126 As usual, a variety of small fixes and improvements, both generic
1127 and configuration-specific. See the ChangeLog for more detail.
1129 *** Changes in GDB-4.12:
1131 * Irix 5 is now supported
1135 GDB-4.12 on the HPPA has a number of changes which make it unable
1136 to debug the output from the currently released versions of GCC and
1137 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
1138 of GCC and GAS, versions of these tools designed to work with GDB-4.12
1139 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
1142 *** Changes in GDB-4.11:
1144 * User visible changes:
1148 The "set remotedebug" option is now consistent between the mips remote
1149 target, remote targets using the gdb-specific protocol, UDI (AMD's
1150 debug protocol for the 29k) and the 88k bug monitor. It is now an
1151 integer specifying a debug level (normally 0 or 1, but 2 means more
1152 debugging info for the mips target).
1154 * DEC Alpha native support
1156 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
1157 debug info, but GDB works fairly well with the DEC compiler and should
1158 work with a future GCC release. See the README file for a few
1159 Alpha-specific notes.
1161 * Preliminary thread implementation
1163 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
1165 * LynxOS native and target support for 386
1167 This release has been hosted on LynxOS 2.2, and also can be configured
1168 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
1171 * Improvements in C++ mangling/demangling.
1173 This release has much better g++ debugging, specifically in name
1174 mangling/demangling, virtual function calls, print virtual table,
1175 call methods, ...etc.
1177 *** Changes in GDB-4.10:
1179 * User visible changes:
1181 Remote debugging using the GDB-specific (`target remote') protocol now
1182 supports the `load' command. This is only useful if you have some
1183 other way of getting the stub to the target system, and you can put it
1184 somewhere in memory where it won't get clobbered by the download.
1186 Filename completion now works.
1188 When run under emacs mode, the "info line" command now causes the
1189 arrow to point to the line specified. Also, "info line" prints
1190 addresses in symbolic form (as well as hex).
1192 All vxworks based targets now support a user settable option, called
1193 vxworks-timeout. This option represents the number of seconds gdb
1194 should wait for responses to rpc's. You might want to use this if
1195 your vxworks target is, perhaps, a slow software simulator or happens
1196 to be on the far side of a thin network line.
1200 This release contains support for using a DEC alpha as a GDB host for
1201 cross debugging. Native alpha debugging is not supported yet.
1204 *** Changes in GDB-4.9:
1208 This is the first GDB release which is accompanied by a matching testsuite.
1209 The testsuite requires installation of dejagnu, which should be available
1210 via ftp from most sites that carry GNU software.
1214 'Cfront' style demangling has had its name changed to 'ARM' style, to
1215 emphasize that it was written from the specifications in the C++ Annotated
1216 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
1217 disclaimers, it still generated too much confusion with users attempting to
1218 use gdb with AT&T cfront.
1222 GDB now uses a standard remote interface to a simulator library.
1223 So far, the library contains simulators for the Zilog Z8001/2, the
1224 Hitachi H8/300, H8/500 and Super-H.
1226 * New targets supported
1228 H8/300 simulator h8300-hitachi-hms or h8300hms
1229 H8/500 simulator h8500-hitachi-hms or h8500hms
1230 SH simulator sh-hitachi-hms or sh
1231 Z8000 simulator z8k-zilog-none or z8ksim
1232 IDT MIPS board over serial line mips-idt-ecoff
1234 Cross-debugging to GO32 targets is supported. It requires a custom
1235 version of the i386-stub.c module which is integrated with the
1236 GO32 memory extender.
1238 * New remote protocols
1240 MIPS remote debugging protocol.
1242 * New source languages supported
1244 This version includes preliminary support for Chill, a Pascal like language
1245 used by telecommunications companies. Chill support is also being integrated
1246 into the GNU compiler, but we don't know when it will be publically available.
1249 *** Changes in GDB-4.8:
1251 * HP Precision Architecture supported
1253 GDB now supports HP PA-RISC machines running HPUX. A preliminary
1254 version of this support was available as a set of patches from the
1255 University of Utah. GDB does not support debugging of programs
1256 compiled with the HP compiler, because HP will not document their file
1257 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
1258 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
1260 Many problems in the preliminary version have been fixed.
1262 * Faster and better demangling
1264 We have improved template demangling and fixed numerous bugs in the GNU style
1265 demangler. It can now handle type modifiers such as `static' or `const'. Wide
1266 character types (wchar_t) are now supported. Demangling of each symbol is now
1267 only done once, and is cached when the symbol table for a file is read in.
1268 This results in a small increase in memory usage for C programs, a moderate
1269 increase in memory usage for C++ programs, and a fantastic speedup in
1272 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
1273 from the specifications in the Annotated Reference Manual, which AT&T's
1274 compiler does not actually implement.
1276 * G++ multiple inheritance compiler problem
1278 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
1279 inheritance lattices was reworked to properly discover ambiguities. We
1280 recently found an example which causes this new algorithm to fail in a
1281 very subtle way, producing bad debug information for those classes.
1282 The file 'gcc.patch' (in this directory) can be applied to gcc to
1283 circumvent the problem. A future GCC release will contain a complete
1286 The previous G++ debug info problem (mentioned below for the gdb-4.7
1287 release) is fixed in gcc version 2.3.2.
1289 * Improved configure script
1291 The `configure' script will now attempt to guess your system type if
1292 you don't supply a host system type. The old scheme of supplying a
1293 host system triplet is preferable over using this. All the magic is
1294 done in the new `config.guess' script. Examine it for details.
1296 We have also brought our configure script much more in line with the FSF's
1297 version. It now supports the --with-xxx options. In particular,
1298 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
1299 The resulting GDB will not be able to read arbitrary object file formats --
1300 only the format ``expected'' to be used on the configured target system.
1301 We hope to make this the default in a future release.
1303 * Documentation improvements
1305 There's new internal documentation on how to modify GDB, and how to
1306 produce clean changes to the code. We implore people to read it
1307 before submitting changes.
1309 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
1310 M4 macros. The new texinfo.tex is provided in this release. Pre-built
1311 `info' files are also provided. To build `info' files from scratch,
1312 you will need the latest `makeinfo' release, which will be available in
1313 a future texinfo-X.Y release.
1315 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
1316 We're not sure exactly which versions have this problem, but it has
1317 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
1318 or better. If that isn't possible, there is a patch in
1319 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
1320 around this problem.
1324 GDB now supports array constants that can be used in expressions typed in by
1325 the user. The syntax is `{element, element, ...}'. Ie: you can now type
1326 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
1329 The new directory `gdb/sparclite' contains a program that demonstrates
1330 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
1332 * New native hosts supported
1334 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
1335 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
1337 * New targets supported
1339 AMD 29k family via UDI a29k-amd-udi or udi29k
1341 * New file formats supported
1343 BFD now supports reading HP/PA-RISC executables (SOM file format?),
1344 HPUX core files, and SCO 3.2v2 core files.
1348 Attaching to processes now works again; thanks for the many bug reports.
1350 We have also stomped on a bunch of core dumps caused by
1351 printf_filtered("%s") problems.
1353 We eliminated a copyright problem on the rpc and ptrace header files
1354 for VxWorks, which was discovered at the last minute during the 4.7
1355 release. You should now be able to build a VxWorks GDB.
1357 You can now interrupt gdb while an attached process is running. This
1358 will cause the attached process to stop, and give control back to GDB.
1360 We fixed problems caused by using too many file descriptors
1361 for reading symbols from object files and libraries. This was
1362 especially a problem for programs that used many (~100) shared
1365 The `step' command now only enters a subroutine if there is line number
1366 information for the subroutine. Otherwise it acts like the `next'
1367 command. Previously, `step' would enter subroutines if there was
1368 any debugging information about the routine. This avoids problems
1369 when using `cc -g1' on MIPS machines.
1371 * Internal improvements
1373 GDB's internal interfaces have been improved to make it easier to support
1374 debugging of multiple languages in the future.
1376 GDB now uses a common structure for symbol information internally.
1377 Minimal symbols (derived from linkage symbols in object files), partial
1378 symbols (from a quick scan of debug information), and full symbols
1379 contain a common subset of information, making it easier to write
1380 shared code that handles any of them.
1382 * New command line options
1384 We now accept --silent as an alias for --quiet.
1388 The memory-mapped-malloc library is now licensed under the GNU Library
1389 General Public License.
1391 *** Changes in GDB-4.7:
1393 * Host/native/target split
1395 GDB has had some major internal surgery to untangle the support for
1396 hosts and remote targets. Now, when you configure GDB for a remote
1397 target, it will no longer load in all of the support for debugging
1398 local programs on the host. When fully completed and tested, this will
1399 ensure that arbitrary host/target combinations are possible.
1401 The primary conceptual shift is to separate the non-portable code in
1402 GDB into three categories. Host specific code is required any time GDB
1403 is compiled on that host, regardless of the target. Target specific
1404 code relates to the peculiarities of the target, but can be compiled on
1405 any host. Native specific code is everything else: it can only be
1406 built when the host and target are the same system. Child process
1407 handling and core file support are two common `native' examples.
1409 GDB's use of /proc for controlling Unix child processes is now cleaner.
1410 It has been split out into a single module under the `target_ops' vector,
1411 plus two native-dependent functions for each system that uses /proc.
1413 * New hosts supported
1415 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
1416 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1417 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
1419 * New targets supported
1421 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1422 68030 and CPU32 m68030-*-*, m68332-*-*
1424 * New native hosts supported
1426 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1427 (386bsd is not well tested yet)
1428 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
1430 * New file formats supported
1432 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
1433 supports reading of `a.out.adobe' object files, which are an a.out
1434 format extended with minimal information about multiple sections.
1438 `show copying' is the same as the old `info copying'.
1439 `show warranty' is the same as `info warrantee'.
1440 These were renamed for consistency. The old commands continue to work.
1442 `info handle' is a new alias for `info signals'.
1444 You can now define pre-command hooks, which attach arbitrary command
1445 scripts to any command. The commands in the hook will be executed
1446 prior to the user's command. You can also create a hook which will be
1447 executed whenever the program stops. See gdb.texinfo.
1451 We now deal with Cfront style name mangling, and can even extract type
1452 info from mangled symbols. GDB can automatically figure out which
1453 symbol mangling style your C++ compiler uses.
1455 Calling of methods and virtual functions has been improved as well.
1459 The crash that occured when debugging Sun Ansi-C compiled binaries is
1460 fixed. This was due to mishandling of the extra N_SO stabs output
1463 We also finally got Ultrix 4.2 running in house, and fixed core file
1464 support, with help from a dozen people on the net.
1466 John M. Farrell discovered that the reason that single-stepping was so
1467 slow on all of the Mips based platforms (primarily SGI and DEC) was
1468 that we were trying to demangle and lookup a symbol used for internal
1469 purposes on every instruction that was being stepped through. Changing
1470 the name of that symbol so that it couldn't be mistaken for a C++
1471 mangled symbol sped things up a great deal.
1473 Rich Pixley sped up symbol lookups in general by getting much smarter
1474 about when C++ symbol mangling is necessary. This should make symbol
1475 completion (TAB on the command line) much faster. It's not as fast as
1476 we'd like, but it's significantly faster than gdb-4.6.
1480 A new user controllable variable 'call_scratch_address' can
1481 specify the location of a scratch area to be used when GDB
1482 calls a function in the target. This is necessary because the
1483 usual method of putting the scratch area on the stack does not work
1484 in systems that have separate instruction and data spaces.
1486 We integrated changes to support the 29k UDI (Universal Debugger
1487 Interface), but discovered at the last minute that we didn't have all
1488 of the appropriate copyright paperwork. We are working with AMD to
1489 resolve this, and hope to have it available soon.
1493 We have sped up the remote serial line protocol, especially for targets
1494 with lots of registers. It now supports a new `expedited status' ('T')
1495 message which can be used in place of the existing 'S' status message.
1496 This allows the remote stub to send only the registers that GDB
1497 needs to make a quick decision about single-stepping or conditional
1498 breakpoints, eliminating the need to fetch the entire register set for
1499 each instruction being stepped through.
1501 The GDB remote serial protocol now implements a write-through cache for
1502 registers, only re-reading the registers if the target has run.
1504 There is also a new remote serial stub for SPARC processors. You can
1505 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
1506 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
1507 processor with a serial port.
1511 Configure.in files have become much easier to read and modify. A new
1512 `table driven' format makes it more obvious what configurations are
1513 supported, and what files each one uses.
1517 There is a new opcodes library which will eventually contain all of the
1518 disassembly routines and opcode tables. At present, it only contains
1519 Sparc and Z8000 routines. This will allow the assembler, debugger, and
1520 disassembler (binutils/objdump) to share these routines.
1522 The libiberty library is now copylefted under the GNU Library General
1523 Public License. This allows more liberal use, and was done so libg++
1524 can use it. This makes no difference to GDB, since the Library License
1525 grants all the rights from the General Public License.
1529 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
1530 reference to the stabs symbol info used by the debugger. It is (as far
1531 as we know) the only published document on this fascinating topic. We
1532 encourage you to read it, compare it to the stabs information on your
1533 system, and send improvements on the document in general (to
1534 bug-gdb@prep.ai.mit.edu).
1536 And, of course, many bugs have been fixed.
1539 *** Changes in GDB-4.6:
1541 * Better support for C++ function names
1543 GDB now accepts as input the "demangled form" of C++ overloaded function
1544 names and member function names, and can do command completion on such names
1545 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
1546 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
1547 Make use of command completion, it is your friend.
1549 GDB also now accepts a variety of C++ mangled symbol formats. They are
1550 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
1551 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
1552 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
1553 for the list of formats.
1555 * G++ symbol mangling problem
1557 Recent versions of gcc have a bug in how they emit debugging information for
1558 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
1559 directory) can be applied to gcc to fix the problem. Alternatively, if you
1560 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
1561 usual symptom is difficulty with setting breakpoints on methods. GDB complains
1562 about the method being non-existent. (We believe that version 2.2.2 of GCC has
1565 * New 'maintenance' command
1567 All of the commands related to hacking GDB internals have been moved out of
1568 the main command set, and now live behind the 'maintenance' command. This
1569 can also be abbreviated as 'mt'. The following changes were made:
1571 dump-me -> maintenance dump-me
1572 info all-breakpoints -> maintenance info breakpoints
1573 printmsyms -> maintenance print msyms
1574 printobjfiles -> maintenance print objfiles
1575 printpsyms -> maintenance print psymbols
1576 printsyms -> maintenance print symbols
1578 The following commands are new:
1580 maintenance demangle Call internal GDB demangler routine to
1581 demangle a C++ link name and prints the result.
1582 maintenance print type Print a type chain for a given symbol
1584 * Change to .gdbinit file processing
1586 We now read the $HOME/.gdbinit file before processing the argv arguments
1587 (e.g. reading symbol files or core files). This allows global parameters to
1588 be set, which will apply during the symbol reading. The ./.gdbinit is still
1589 read after argv processing.
1591 * New hosts supported
1593 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
1595 GNU/Linux support i386-unknown-linux or linux
1597 We are also including code to support the HP/PA running BSD and HPUX. This
1598 is almost guaranteed not to work, as we didn't have time to test or build it
1599 for this release. We are including it so that the more adventurous (or
1600 masochistic) of you can play with it. We also had major problems with the
1601 fact that the compiler that we got from HP doesn't support the -g option.
1604 * New targets supported
1606 Hitachi H8/300 h8300-hitachi-hms or h8300hms
1608 * More smarts about finding #include files
1610 GDB now remembers the compilation directory for all include files, and for
1611 all files from which C is generated (like yacc and lex sources). This
1612 greatly improves GDB's ability to find yacc/lex sources, and include files,
1613 especially if you are debugging your program from a directory different from
1614 the one that contains your sources.
1616 We also fixed a bug which caused difficulty with listing and setting
1617 breakpoints in include files which contain C code. (In the past, you had to
1618 try twice in order to list an include file that you hadn't looked at before.)
1620 * Interesting infernals change
1622 GDB now deals with arbitrary numbers of sections, where the symbols for each
1623 section must be relocated relative to that section's landing place in the
1624 target's address space. This work was needed to support ELF with embedded
1625 stabs used by Solaris-2.0.
1627 * Bug fixes (of course!)
1629 There have been loads of fixes for the following things:
1630 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
1631 i960, stabs, DOS(GO32), procfs, etc...
1633 See the ChangeLog for details.
1635 *** Changes in GDB-4.5:
1637 * New machines supported (host and target)
1639 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
1641 SGI Irix-4.x mips-sgi-irix4 or iris4
1643 * New malloc package
1645 GDB now uses a new memory manager called mmalloc, based on gmalloc.
1646 Mmalloc is capable of handling mutiple heaps of memory. It is also
1647 capable of saving a heap to a file, and then mapping it back in later.
1648 This can be used to greatly speedup the startup of GDB by using a
1649 pre-parsed symbol table which lives in a mmalloc managed heap. For
1650 more details, please read mmalloc/mmalloc.texi.
1654 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
1655 'help info proc' for details.
1657 * MIPS ecoff symbol table format
1659 The code that reads MIPS symbol table format is now supported on all hosts.
1660 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
1663 * File name changes for MS-DOS
1665 Many files in the config directories have been renamed to make it easier to
1666 support GDB on MS-DOSe systems (which have very restrictive file name
1667 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
1668 environment) is close to working but has some remaining problems. Note
1669 that debugging of DOS programs is not supported, due to limitations
1670 in the ``operating system'', but it can be used to host cross-debugging.
1672 * Cross byte order fixes
1674 Many fixes have been made to support cross debugging of Sparc and MIPS
1675 targets from hosts whose byte order differs.
1677 * New -mapped and -readnow options
1679 If memory-mapped files are available on your system through the 'mmap'
1680 system call, you can use the -mapped option on the `file' or
1681 `symbol-file' commands to cause GDB to write the symbols from your
1682 program into a reusable file. If the program you are debugging is
1683 called `/path/fred', the mapped symbol file will be `./fred.syms'.
1684 Future GDB debugging sessions will notice the presence of this file,
1685 and will quickly map in symbol information from it, rather than reading
1686 the symbol table from the executable program. Using the '-mapped'
1687 option in a GDB `file' or `symbol-file' command has the same effect as
1688 starting GDB with the '-mapped' command-line option.
1690 You can cause GDB to read the entire symbol table immediately by using
1691 the '-readnow' option with any of the commands that load symbol table
1692 information (or on the GDB command line). This makes the command
1693 slower, but makes future operations faster.
1695 The -mapped and -readnow options are typically combined in order to
1696 build a `fred.syms' file that contains complete symbol information.
1697 A simple GDB invocation to do nothing but build a `.syms' file for future
1700 gdb -batch -nx -mapped -readnow programname
1702 The `.syms' file is specific to the host machine on which GDB is run.
1703 It holds an exact image of GDB's internal symbol table. It cannot be
1704 shared across multiple host platforms.
1706 * longjmp() handling
1708 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
1709 siglongjmp() without losing control. This feature has not yet been ported to
1710 all systems. It currently works on many 386 platforms, all MIPS-based
1711 platforms (SGI, DECstation, etc), and Sun3/4.
1715 Preliminary work has been put in to support the new Solaris OS from Sun. At
1716 this time, it can control and debug processes, but it is not capable of
1721 As always, many many bug fixes. The major areas were with g++, and mipsread.
1722 People using the MIPS-based platforms should experience fewer mysterious
1723 crashes and trashed symbol tables.
1725 *** Changes in GDB-4.4:
1727 * New machines supported (host and target)
1729 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1731 BSD Reno on Vax vax-dec-bsd
1732 Ultrix on Vax vax-dec-ultrix
1734 * New machines supported (target)
1736 AMD 29000 embedded, using EBMON a29k-none-none
1740 GDB continues to improve its handling of C++. `References' work better.
1741 The demangler has also been improved, and now deals with symbols mangled as
1742 per the Annotated C++ Reference Guide.
1744 GDB also now handles `stabs' symbol information embedded in MIPS
1745 `ecoff' symbol tables. Since the ecoff format was not easily
1746 extensible to handle new languages such as C++, this appeared to be a
1747 good way to put C++ debugging info into MIPS binaries. This option
1748 will be supported in the GNU C compiler, version 2, when it is
1751 * New features for SVR4
1753 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
1754 shared libraries. Debugging dynamically linked programs should present
1755 only minor differences from debugging statically linked programs.
1757 The `info proc' command will print out information about any process
1758 on an SVR4 system (including the one you are debugging). At the moment,
1759 it prints the address mappings of the process.
1761 If you bring up GDB on another SVR4 system, please send mail to
1762 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
1764 * Better dynamic linking support in SunOS
1766 Reading symbols from shared libraries which contain debugging symbols
1767 now works properly. However, there remain issues such as automatic
1768 skipping of `transfer vector' code during function calls, which
1769 make it harder to debug code in a shared library, than to debug the
1770 same code linked statically.
1774 GDB is now using the latest `getopt' routines from the FSF. This
1775 version accepts the -- prefix for options with long names. GDB will
1776 continue to accept the old forms (-option and +option) as well.
1777 Various single letter abbreviations for options have been explicity
1778 added to the option table so that they won't get overshadowed in the
1779 future by other options that begin with the same letter.
1783 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
1784 Many assorted bugs have been handled. Many more remain to be handled.
1785 See the various ChangeLog files (primarily in gdb and bfd) for details.
1788 *** Changes in GDB-4.3:
1790 * New machines supported (host and target)
1792 Amiga 3000 running Amix m68k-cbm-svr4 or amix
1793 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
1794 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1796 * Almost SCO Unix support
1798 We had hoped to support:
1799 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1800 (except for core file support), but we discovered very late in the release
1801 that it has problems with process groups that render gdb unusable. Sorry
1802 about that. I encourage people to fix it and post the fixes.
1804 * Preliminary ELF and DWARF support
1806 GDB can read ELF object files on System V Release 4, and can handle
1807 debugging records for C, in DWARF format, in ELF files. This support
1808 is preliminary. If you bring up GDB on another SVR4 system, please
1809 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
1814 GDB now uses the latest `readline' library. One user-visible change
1815 is that two tabs will list possible command completions, which previously
1816 required typing M-? (meta-question mark, or ESC ?).
1820 The `stepi' bug that many of you noticed has been squashed.
1821 Many bugs in C++ have been handled. Many more remain to be handled.
1822 See the various ChangeLog files (primarily in gdb and bfd) for details.
1824 * State of the MIPS world (in case you wondered):
1826 GDB can understand the symbol tables emitted by the compilers
1827 supplied by most vendors of MIPS-based machines, including DEC. These
1828 symbol tables are in a format that essentially nobody else uses.
1830 Some versions of gcc come with an assembler post-processor called
1831 mips-tfile. This program is required if you want to do source-level
1832 debugging of gcc-compiled programs. I believe FSF does not ship
1833 mips-tfile with gcc version 1, but it will eventually come with gcc
1836 Debugging of g++ output remains a problem. g++ version 1.xx does not
1837 really support it at all. (If you're lucky, you should be able to get
1838 line numbers and stack traces to work, but no parameters or local
1839 variables.) With some work it should be possible to improve the
1842 When gcc version 2 is released, you will have somewhat better luck.
1843 However, even then you will get confusing results for inheritance and
1846 We will eventually provide full debugging of g++ output on
1847 DECstations. This will probably involve some kind of stabs-in-ecoff
1848 encapulation, but the details have not been worked out yet.
1851 *** Changes in GDB-4.2:
1853 * Improved configuration
1855 Only one copy of `configure' exists now, and it is not self-modifying.
1856 Porting BFD is simpler.
1860 The `step' and `next' commands now only stop at the first instruction
1861 of a source line. This prevents the multiple stops that used to occur
1862 in switch statements, for-loops, etc. `Step' continues to stop if a
1863 function that has debugging information is called within the line.
1867 Lots of small bugs fixed. More remain.
1869 * New host supported (not target)
1871 Intel 386 PC clone running Mach i386-none-mach
1874 *** Changes in GDB-4.1:
1876 * Multiple source language support
1878 GDB now has internal scaffolding to handle several source languages.
1879 It determines the type of each source file from its filename extension,
1880 and will switch expression parsing and number formatting to match the
1881 language of the function in the currently selected stack frame.
1882 You can also specifically set the language to be used, with
1883 `set language c' or `set language modula-2'.
1887 GDB now has preliminary support for the GNU Modula-2 compiler,
1888 currently under development at the State University of New York at
1889 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
1890 continue through the fall of 1991 and into 1992.
1892 Other Modula-2 compilers are currently not supported, and attempting to
1893 debug programs compiled with them will likely result in an error as the
1894 symbol table is read. Feel free to work on it, though!
1896 There are hooks in GDB for strict type checking and range checking,
1897 in the `Modula-2 philosophy', but they do not currently work.
1901 GDB can now write to executable and core files (e.g. patch
1902 a variable's value). You must turn this switch on, specify
1903 the file ("exec foo" or "core foo"), *then* modify it, e.g.
1904 by assigning a new value to a variable. Modifications take
1907 * Automatic SunOS shared library reading
1909 When you run your program, GDB automatically determines where its
1910 shared libraries (if any) have been loaded, and reads their symbols.
1911 The `share' command is no longer needed. This also works when
1912 examining core files.
1916 You can specify the number of lines that the `list' command shows.
1919 * New machines supported (host and target)
1921 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1922 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
1923 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
1925 * New hosts supported (not targets)
1927 IBM RT/PC: romp-ibm-aix or rtpc
1929 * New targets supported (not hosts)
1931 AMD 29000 embedded with COFF a29k-none-coff
1932 AMD 29000 embedded with a.out a29k-none-aout
1933 Ultracomputer remote kernel debug a29k-nyu-kern
1935 * New remote interfaces
1941 *** Changes in GDB-4.0:
1945 Wide output is wrapped at good places to make the output more readable.
1947 Gdb now supports cross-debugging from a host machine of one type to a
1948 target machine of another type. Communication with the target system
1949 is over serial lines. The ``target'' command handles connecting to the
1950 remote system; the ``load'' command will download a program into the
1951 remote system. Serial stubs for the m68k and i386 are provided. Gdb
1952 also supports debugging of realtime processes running under VxWorks,
1953 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
1954 stub on the target system.
1956 New CPUs supported include the AMD 29000 and Intel 960.
1958 GDB now reads object files and symbol tables via a ``binary file''
1959 library, which allows a single copy of GDB to debug programs of multiple
1960 object file types such as a.out and coff.
1962 There is now a GDB reference card in "doc/refcard.tex". (Make targets
1963 refcard.dvi and refcard.ps are available to format it).
1966 * Control-Variable user interface simplified
1968 All variables that control the operation of the debugger can be set
1969 by the ``set'' command, and displayed by the ``show'' command.
1971 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
1972 ``Show prompt'' produces the response:
1973 Gdb's prompt is new-gdb=>.
1975 What follows are the NEW set commands. The command ``help set'' will
1976 print a complete list of old and new set commands. ``help set FOO''
1977 will give a longer description of the variable FOO. ``show'' will show
1978 all of the variable descriptions and their current settings.
1980 confirm on/off: Enables warning questions for operations that are
1981 hard to recover from, e.g. rerunning the program while
1982 it is already running. Default is ON.
1984 editing on/off: Enables EMACS style command line editing
1985 of input. Previous lines can be recalled with
1986 control-P, the current line can be edited with control-B,
1987 you can search for commands with control-R, etc.
1990 history filename NAME: NAME is where the gdb command history
1991 will be stored. The default is .gdb_history,
1992 or the value of the environment variable
1995 history size N: The size, in commands, of the command history. The
1996 default is 256, or the value of the environment variable
1999 history save on/off: If this value is set to ON, the history file will
2000 be saved after exiting gdb. If set to OFF, the
2001 file will not be saved. The default is OFF.
2003 history expansion on/off: If this value is set to ON, then csh-like
2004 history expansion will be performed on
2005 command line input. The default is OFF.
2007 radix N: Sets the default radix for input and output. It can be set
2008 to 8, 10, or 16. Note that the argument to "radix" is interpreted
2009 in the current radix, so "set radix 10" is always a no-op.
2011 height N: This integer value is the number of lines on a page. Default
2012 is 24, the current `stty rows'' setting, or the ``li#''
2013 setting from the termcap entry matching the environment
2016 width N: This integer value is the number of characters on a line.
2017 Default is 80, the current `stty cols'' setting, or the ``co#''
2018 setting from the termcap entry matching the environment
2021 Note: ``set screensize'' is obsolete. Use ``set height'' and
2022 ``set width'' instead.
2024 print address on/off: Print memory addresses in various command displays,
2025 such as stack traces and structure values. Gdb looks
2026 more ``symbolic'' if you turn this off; it looks more
2027 ``machine level'' with it on. Default is ON.
2029 print array on/off: Prettyprint arrays. New convenient format! Default
2032 print demangle on/off: Print C++ symbols in "source" form if on,
2035 print asm-demangle on/off: Same, for assembler level printouts
2038 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
2041 * Support for Epoch Environment.
2043 The epoch environment is a version of Emacs v18 with windowing. One
2044 new command, ``inspect'', is identical to ``print'', except that if you
2045 are running in the epoch environment, the value is printed in its own
2049 * Support for Shared Libraries
2051 GDB can now debug programs and core files that use SunOS shared libraries.
2052 Symbols from a shared library cannot be referenced
2053 before the shared library has been linked with the program (this
2054 happens after you type ``run'' and before the function main() is entered).
2055 At any time after this linking (including when examining core files
2056 from dynamically linked programs), gdb reads the symbols from each
2057 shared library when you type the ``sharedlibrary'' command.
2058 It can be abbreviated ``share''.
2060 sharedlibrary REGEXP: Load shared object library symbols for files
2061 matching a unix regular expression. No argument
2062 indicates to load symbols for all shared libraries.
2064 info sharedlibrary: Status of loaded shared libraries.
2069 A watchpoint stops execution of a program whenever the value of an
2070 expression changes. Checking for this slows down execution
2071 tremendously whenever you are in the scope of the expression, but is
2072 quite useful for catching tough ``bit-spreader'' or pointer misuse
2073 problems. Some machines such as the 386 have hardware for doing this
2074 more quickly, and future versions of gdb will use this hardware.
2076 watch EXP: Set a watchpoint (breakpoint) for an expression.
2078 info watchpoints: Information about your watchpoints.
2080 delete N: Deletes watchpoint number N (same as breakpoints).
2081 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
2082 enable N: Re-enables watchpoint number N (same as breakpoints).
2085 * C++ multiple inheritance
2087 When used with a GCC version 2 compiler, GDB supports multiple inheritance
2090 * C++ exception handling
2092 Gdb now supports limited C++ exception handling. Besides the existing
2093 ability to breakpoint on an exception handler, gdb can breakpoint on
2094 the raising of an exception (before the stack is peeled back to the
2097 catch FOO: If there is a FOO exception handler in the dynamic scope,
2098 set a breakpoint to catch exceptions which may be raised there.
2099 Multiple exceptions (``catch foo bar baz'') may be caught.
2101 info catch: Lists all exceptions which may be caught in the
2102 current stack frame.
2105 * Minor command changes
2107 The command ``call func (arg, arg, ...)'' now acts like the print
2108 command, except it does not print or save a value if the function's result
2109 is void. This is similar to dbx usage.
2111 The ``up'' and ``down'' commands now always print the frame they end up
2112 at; ``up-silently'' and `down-silently'' can be used in scripts to change
2113 frames without printing.
2115 * New directory command
2117 'dir' now adds directories to the FRONT of the source search path.
2118 The path starts off empty. Source files that contain debug information
2119 about the directory in which they were compiled can be found even
2120 with an empty path; Sun CC and GCC include this information. If GDB can't
2121 find your source file in the current directory, type "dir .".
2123 * Configuring GDB for compilation
2125 For normal use, type ``./configure host''. See README or gdb.texinfo
2128 GDB now handles cross debugging. If you are remotely debugging between
2129 two different machines, type ``./configure host -target=targ''.
2130 Host is the machine where GDB will run; targ is the machine
2131 where the program that you are debugging will run.