What has changed in GDB? (Organized release by release) *** Changes since GDB 5.2: * ``gdbserver'' now supports multithreaded applications on some targets Support for multithreaded applications using LinuxThreads has been added for arm*-*-linux*, i[3456]86-*-linux*, mips*-*-linux*, powerpc*-*-linux*, and sh*-*-linux*. * GDB now supports C/C++ preprocessor macros. GDB now expands preprocessor macro invocations in C/C++ expressions, and provides various commands for showing macro definitions and how they expand. Most compilers don't include information about macros in the debugging information by default. In GCC 3.1, for example, you need to compile your program with the options `-gdwarf-2 -g3'. If the macro information is present in the executable, GDB will read it. Here are the new commands for working with macros: ** macro expand EXPRESSION Expand any macro invocations in expression, and show the result. ** show macro MACRO-NAME Show the definition of the macro named MACRO-NAME, and where it was defined. * Multi-arched targets. DEC Alpha (partial) alpha*-*-* DEC VAX (partial) vax-*-* NEC V850 v850-*-* National Semiconductor NS32000 (partial) ns32k-*-* Motorola 68000 (partial) m68k-*-* Motorola MCORE mcore-*-* * New targets. Atmel AVR avr*-*-* Fujitsu FRV architecture added by Red Hat frv*-*-* * New native configurations Alpha NetBSD alpha*-*-netbsd* SH NetBSD sh*-*-netbsdelf* MIPS NetBSD mips*-*-netbsd* UltraSPARC NetBSD sparc64-*-netbsd* * OBSOLETE configurations and files Configurations that have been declared obsolete in this release have been commented out. Unless there is activity to revive these configurations, the next release of GDB will have their sources permanently REMOVED. Mitsubishi D30V d30v-*-* Fujitsu FR30 fr30-*-elf* * REMOVED configurations and files AMD 29k family via UDI a29k-amd-udi, udi29k A29K VxWorks a29k-*-vxworks AMD 29000 embedded, using EBMON a29k-none-none AMD 29000 embedded with COFF a29k-none-coff AMD 29000 embedded with a.out a29k-none-aout testsuite/gdb.hp/gdb.threads-hp/ directory * New command "set max-user-call-depth " This command allows the user to limit the call depth of user-defined commands. The default is 1024. * Changes in FreeBSD/i386 native debugging. Support for the "generate-core-file" has been added. * New commands "dump", "append", and "restore". These commands allow data to be copied from target memory to a bfd-format or binary file (dump and append), and back from a file into memory (restore). *** Changes in GDB 5.2: * New command "set trust-readonly-sections on[off]". This command is a hint that tells gdb that read-only sections really are read-only (ie. that their contents will not change). In this mode, gdb will go to the object file rather than the target to read memory from read-only sections (such as ".text"). This can be a significant performance improvement on some (notably embedded) targets. * New command "generate-core-file" (or "gcore"). This new gdb command allows the user to drop a core file of the child process state at any time. So far it's been implemented only for GNU/Linux and Solaris, but should be relatively easily ported to other hosts. Argument is core file name (defaults to core.). * New command line option GDB now accepts --pid or -p followed by a process id. * Change in command line behavior -- corefiles vs. process ids. There is a subtle behavior in the way in which GDB handles command line arguments. The first non-flag argument is always a program to debug, but the second non-flag argument may either be a corefile or a process id. Previously, GDB would attempt to open the second argument as a corefile, and if that failed, would issue a superfluous error message and then attempt to attach it as a process. Now, if the second argument begins with a non-digit, it will be treated as a corefile. If it begins with a digit, GDB will attempt to attach it as a process, and if no such process is found, will then attempt to open it as a corefile. * Changes in ARM configurations. Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD configuration is fully multi-arch. * New native configurations ARM NetBSD arm*-*-netbsd* x86 OpenBSD i[3456]86-*-openbsd* AMD x86-64 running GNU/Linux x86_64-*-linux-* Sparc64 running FreeBSD sparc64-*-freebsd* * New targets Sanyo XStormy16 xstormy16-elf * OBSOLETE configurations and files Configurations that have been declared obsolete in this release have been commented out. Unless there is activity to revive these configurations, the next release of GDB will have their sources permanently REMOVED. AMD 29k family via UDI a29k-amd-udi, udi29k A29K VxWorks a29k-*-vxworks AMD 29000 embedded, using EBMON a29k-none-none AMD 29000 embedded with COFF a29k-none-coff AMD 29000 embedded with a.out a29k-none-aout testsuite/gdb.hp/gdb.threads-hp/ directory * REMOVED configurations and files TI TMS320C80 tic80-*-* WDC 65816 w65-*-* PowerPC Solaris powerpcle-*-solaris* PowerPC Windows NT powerpcle-*-cygwin32 PowerPC Netware powerpc-*-netware* Harris/CXUX m88k m88*-harris-cxux* Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-* ns32k-utek-sysv* ns32k-utek-* SunOS 4.0.Xi on i386 i[3456]86-*-sunos* Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern* Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news ISI Optimum V (3.05) under 4.3bsd. m68*-isi-* Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos* * Changes to command line processing The new `--args' feature can be used to specify command-line arguments for the inferior from gdb's command line. * Changes to key bindings There is a new `operate-and-get-next' function bound to `C-o'. *** Changes in GDB 5.1.1 Fix compile problem on DJGPP. Fix a problem with floating-point registers on the i386 being corrupted. Fix to stop GDB crashing on .debug_str debug info. Numerous documentation fixes. Numerous testsuite fixes. *** Changes in GDB 5.1: * New native configurations Alpha FreeBSD alpha*-*-freebsd* x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]* MIPS GNU/Linux mips*-*-linux* MIPS SGI Irix 6.x mips*-sgi-irix6* ia64 AIX ia64-*-aix* s390 and s390x GNU/Linux {s390,s390x}-*-linux* * New targets Motorola 68HC11 and 68HC12 m68hc11-elf CRIS cris-axis UltraSparc running GNU/Linux sparc64-*-linux* * OBSOLETE configurations and files x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*, Harris/CXUX m88k m88*-harris-cxux* Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-* ns32k-utek-sysv* ns32k-utek-* TI TMS320C80 tic80-*-* WDC 65816 w65-*-* Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern* PowerPC Solaris powerpcle-*-solaris* PowerPC Windows NT powerpcle-*-cygwin32 PowerPC Netware powerpc-*-netware* SunOS 4.0.Xi on i386 i[3456]86-*-sunos* Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news ISI Optimum V (3.05) under 4.3bsd. m68*-isi-* Apple Macintosh (MPW) host N/A stuff.c (Program to stuff files into a specially prepared space in kdb) kdb-start.c (Main loop for the standalone kernel debugger) Configurations that have been declared obsolete in this release have been commented out. Unless there is activity to revive these configurations, the next release of GDB will have their sources permanently REMOVED. * REMOVED configurations and files Altos 3068 m68*-altos-* Convex c1-*-*, c2-*-* Pyramid pyramid-*-* ARM RISCix arm-*-* (as host) Tahoe tahoe-*-* ser-ocd.c *-*-* * GDB has been converted to ISO C. GDB's source code has been converted to ISO C. In particular, the sources are fully protoized, and rely on standard headers being present. * Other news: * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM. * The MI enabled by default. The new machine oriented interface (MI) introduced in GDB 5.0 has been revised and enabled by default. Packages which use GDB as a debugging engine behind a UI or another front end are encouraged to switch to using the GDB/MI interface, instead of the old annotations interface which is now deprecated. * Support for debugging Pascal programs. GDB now includes support for debugging Pascal programs. The following main features are supported: - Pascal-specific data types such as sets; - automatic recognition of Pascal sources based on file-name extension; - Pascal-style display of data types, variables, and functions; - a Pascal expression parser. However, some important features are not yet supported. - Pascal string operations are not supported at all; - there are some problems with boolean types; - Pascal type hexadecimal constants are not supported because they conflict with the internal variables format; - support for Pascal objects and classes is not full yet; - unlike Pascal, GDB is case-sensitive for symbol names. * Changes in completion. Commands such as `shell', `run' and `set args', which pass arguments to inferior programs, now complete on file names, similar to what users expect at the shell prompt. Commands which accept locations, such as `disassemble', `print', `breakpoint', `until', etc. now complete on filenames as well as program symbols. Thus, if you type "break foob TAB", and the source files linked into the programs include `foobar.c', that file name will be one of the candidates for completion. However, file names are not considered for completion after you typed a colon that delimits a file name from a name of a function in that file, as in "break foo.c:bar". `set demangle-style' completes on available demangling styles. * New platform-independent commands: It is now possible to define a post-hook for a command as well as a hook that runs before the command. For more details, see the documentation of `hookpost' in the GDB manual. * Changes in GNU/Linux native debugging. Support for debugging multi-threaded programs has been completely revised for all platforms except m68k and sparc. You can now debug as many threads as your system allows you to have. Attach/detach is supported for multi-threaded programs. Support for SSE registers was added for x86. This doesn't work for multi-threaded programs though. * Changes in MIPS configurations. Multi-arch support is enabled for all MIPS configurations. GDB can now be built as native debugger on SGI Irix 6.x systems for debugging n32 executables. (Debugging 64-bit executables is not yet supported.) * Unified support for hardware watchpoints in all x86 configurations. Most (if not all) native x86 configurations support hardware-assisted breakpoints and watchpoints in a unified manner. This support implements debug register sharing between watchpoints, which allows to put a virtually infinite number of watchpoints on the same address, and also supports watching regions up to 16 bytes with several debug registers. The new maintenance command `maintenance show-debug-regs' toggles debugging print-outs in functions that insert, remove, and test watchpoints and hardware breakpoints. * Changes in the DJGPP native configuration. New command ``info dos sysinfo'' displays assorted information about the CPU, OS, memory, and DPMI server. New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt'' display information about segment descriptors stored in GDT, LDT, and IDT. New commands ``info dos pde'' and ``info dos pte'' display entries from Page Directory and Page Tables (for now works with CWSDPMI only). New command ``info dos address-pte'' displays the Page Table entry for a given linear address. GDB can now pass command lines longer than 126 characters to the program being debugged (requires an update to the libdbg.a library which is part of the DJGPP development kit). DWARF2 debug info is now supported. It is now possible to `step' and `next' through calls to `longjmp'. * Changes in documentation. All GDB documentation was converted to GFDL, the GNU Free Documentation License. Tracepoints-related commands are now fully documented in the GDB manual. TUI, the Text-mode User Interface, is now documented in the manual. Tracepoints-related commands are now fully documented in the GDB manual. The "GDB Internals" manual now has an index. It also includes documentation of `ui_out' functions, GDB coding standards, x86 hardware watchpoints, and memory region attributes. * GDB's version number moved to ``version.in'' The Makefile variable VERSION has been replaced by the file ``version.in''. People creating GDB distributions should update the contents of this file. * gdba.el deleted GUD support is now a standard part of the EMACS distribution. *** Changes in GDB 5.0: * Improved support for debugging FP programs on x86 targets Unified and much-improved support for debugging floating-point programs on all x86 targets. In particular, ``info float'' now displays the FP registers in the same format on all x86 targets, with greater level of detail. * Improvements and bugfixes in hardware-assisted watchpoints It is now possible to watch array elements, struct members, and bitfields with hardware-assisted watchpoints. Data-read watchpoints on x86 targets no longer erroneously trigger when the address is written. * Improvements in the native DJGPP version of GDB The distribution now includes all the scripts and auxiliary files necessary to build the native DJGPP version on MS-DOS/MS-Windows machines ``out of the box''. The DJGPP version can now debug programs that use signals. It is possible to catch signals that happened in the debuggee, deliver signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal would kill the program being debugged.) Programs that hook hardware interrupts (keyboard, timer, etc.) can also be debugged. It is now possible to debug DJGPP programs that redirect their standard handles or switch them to raw (as opposed to cooked) mode, or even close them. The command ``run < foo > bar'' works as expected, and ``info terminal'' reports useful information about the debuggee's terminal, including raw/cooked mode, redirection, etc. The DJGPP version now uses termios functions for console I/O, which enables debugging graphics programs. Interrupting GDB with Ctrl-C also works. DOS-style file names with drive letters are now fully supported by GDB. It is now possible to debug DJGPP programs that switch their working directory. It is also possible to rerun the debuggee any number of times without restarting GDB; thus, you can use the same setup, breakpoints, etc. for many debugging sessions. * New native configurations ARM GNU/Linux arm*-*-linux* PowerPC GNU/Linux powerpc-*-linux* * New targets Motorola MCore mcore-*-* x86 VxWorks i[3456]86-*-vxworks* PowerPC VxWorks powerpc-*-vxworks* TI TMS320C80 tic80-*-* * OBSOLETE configurations Altos 3068 m68*-altos-* Convex c1-*-*, c2-*-* Pyramid pyramid-*-* ARM RISCix arm-*-* (as host) Tahoe tahoe-*-* Configurations that have been declared obsolete will be commented out, but the code will be left in place. If there is no activity to revive these configurations before the next release of GDB, the sources will be permanently REMOVED. * Gould support removed Support for the Gould PowerNode and NP1 has been removed. * New features for SVR4 On SVR4 native platforms (such as Solaris), if you attach to a process without first loading a symbol file, GDB will now attempt to locate and load symbols from the running process's executable file. * Many C++ enhancements C++ support has been greatly improved. Overload resolution now works properly in almost all cases. RTTI support is on the way. * Remote targets can connect to a sub-program A popen(3) style serial-device has been added. This device starts a sub-process (such as a stand-alone simulator) and then communicates with that. The sub-program to run is specified using the syntax ``| '' vis: (gdb) set remotedebug 1 (gdb) target extended-remote |mn10300-elf-sim program-args * MIPS 64 remote protocol A long standing bug in the mips64 remote protocol where by GDB expected certain 32 bit registers (ex SR) to be transfered as 32 instead of 64 bits has been fixed. The command ``set remote-mips64-transfers-32bit-regs on'' has been added to provide backward compatibility with older versions of GDB. * ``set remotebinarydownload'' replaced by ``set remote X-packet'' The command ``set remotebinarydownload'' command has been replaced by ``set remote X-packet''. Other commands in ``set remote'' family include ``set remote P-packet''. * Breakpoint commands accept ranges. The breakpoint commands ``enable'', ``disable'', and ``delete'' now accept a range of breakpoints, e.g. ``5-7''. The tracepoint command ``tracepoint passcount'' also accepts a range of tracepoints. * ``apropos'' command added. The ``apropos'' command searches through command names and documentation strings, printing out matches, making it much easier to try to find a command that does what you are looking for. * New MI interface A new machine oriented interface (MI) has been added to GDB. This interface is designed for debug environments running GDB as a separate process. This is part of the long term libGDB project. See the "GDB/MI" chapter of the GDB manual for further information. It can be enabled by configuring with: .../configure --enable-gdbmi *** Changes in GDB-4.18: * New native configurations HP-UX 10.20 hppa*-*-hpux10.20 HP-UX 11.x hppa*-*-hpux11.0* M68K GNU/Linux m68*-*-linux* * New targets Fujitsu FR30 fr30-*-elf* Intel StrongARM strongarm-*-* Mitsubishi D30V d30v-*-* * OBSOLETE configurations Gould PowerNode, NP1 np1-*-*, pn-*-* Configurations that have been declared obsolete will be commented out, but the code will be left in place. If there is no activity to revive these configurations before the next release of GDB, the sources will be permanently REMOVED. * ANSI/ISO C As a compatibility experiment, GDB's source files buildsym.h and buildsym.c have been converted to pure standard C, no longer containing any K&R compatibility code. We believe that all systems in use today either come with a standard C compiler, or have a GCC port available. If this is not true, please report the affected configuration to bug-gdb@gnu.org immediately. See the README file for information about getting a standard C compiler if you don't have one already. * Readline 2.2 GDB now uses readline 2.2. * set extension-language You can now control the mapping between filename extensions and source languages by using the `set extension-language' command. For instance, you can ask GDB to treat .c files as C++ by saying set extension-language .c c++ The command `info extensions' lists all of the recognized extensions and their associated languages. * Setting processor type for PowerPC and RS/6000 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target, you can use the `set processor' command to specify what variant of the PowerPC family you are debugging. The command set processor NAME sets the PowerPC/RS6000 variant to NAME. GDB knows about the following PowerPC and RS6000 variants: ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code rs6000 IBM RS6000 ("POWER") architecture, user-level view 403 IBM PowerPC 403 403GC IBM PowerPC 403GC 505 Motorola PowerPC 505 860 Motorola PowerPC 860 or 850 601 Motorola PowerPC 601 602 Motorola PowerPC 602 603 Motorola/IBM PowerPC 603 or 603e 604 Motorola PowerPC 604 or 604e 750 Motorola/IBM PowerPC 750 or 750 At the moment, this command just tells GDB what to name the special-purpose processor registers. Since almost all the affected registers are inaccessible to user-level programs, this command is only useful for remote debugging in its present form. * HP-UX support Thanks to a major code donation from Hewlett-Packard, GDB now has much more extensive support for HP-UX. Added features include shared library support, kernel threads and hardware watchpoints for 11.00, support for HP's ANSI C and C++ compilers, and a compatibility mode for xdb and dbx commands. * Catchpoints HP's donation includes the new concept of catchpoints, which is a generalization of the old catch command. On HP-UX, it is now possible to catch exec, fork, and vfork, as well as library loading. This means that the existing catch command has changed; its first argument now specifies the type of catch to be set up. See the output of "help catch" for a list of catchpoint types. * Debugging across forks On HP-UX, you can choose which process to debug when a fork() happens in the inferior. * TUI HP has donated a curses-based terminal user interface (TUI). To get it, build with --enable-tui. Although this can be enabled for any configuration, at present it only works for native HP debugging. * GDB remote protocol additions A new protocol packet 'X' that writes binary data is now available. Default behavior is to try 'X', then drop back to 'M' if the stub fails to respond. The settable variable `remotebinarydownload' allows explicit control over the use of 'X'. For 64-bit targets, the memory packets ('M' and 'm') can now contain a full 64-bit address. The command set remoteaddresssize 32 can be used to revert to the old behaviour. For existing remote stubs the change should not be noticed, as the additional address information will be discarded. In order to assist in debugging stubs, you may use the maintenance command `packet' to send any text string to the stub. For instance, maint packet heythere sends the packet "$heythere#". Note that it is very easy to disrupt a debugging session by sending the wrong packet at the wrong time. The compare-sections command allows you to compare section data on the target to what is in the executable file without uploading or downloading, by comparing CRC checksums. * Tracing can collect general expressions You may now collect general expressions at tracepoints. This requires further additions to the target-side stub; see tracepoint.c and doc/agentexpr.texi for further details. * mask-address variable for Mips For Mips targets, you may control the zeroing of the upper 32 bits of a 64-bit address by entering `set mask-address on'. This is mainly of interest to users of embedded R4xxx and R5xxx processors. * Higher serial baud rates GDB's serial code now allows you to specify baud rates 57600, 115200, 230400, and 460800 baud. (Note that your host system may not be able to achieve all of these rates.) * i960 simulator The i960 configuration now includes an initial implementation of a builtin simulator, contributed by Jim Wilson. *** Changes in GDB-4.17: * New native configurations Alpha GNU/Linux alpha*-*-linux* Unixware 2.x i[3456]86-unixware2* Irix 6.x mips*-sgi-irix6* PowerPC GNU/Linux powerpc-*-linux* PowerPC Solaris powerpcle-*-solaris* Sparc GNU/Linux sparc-*-linux* Motorola sysV68 R3V7.1 m68k-motorola-sysv * New targets Argonaut Risc Chip (ARC) arc-*-* Hitachi H8/300S h8300*-*-* Matsushita MN10200 w/simulator mn10200-*-* Matsushita MN10300 w/simulator mn10300-*-* MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf* MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf* MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf* Mitsubishi D10V w/simulator d10v-*-* Mitsubishi M32R/D w/simulator m32r-*-elf* Tsqware Sparclet sparclet-*-* NEC V850 w/simulator v850-*-* * New debugging protocols ARM with RDI protocol arm*-*-* M68K with dBUG monitor m68*-*-{aout,coff,elf} DDB and LSI variants of PMON protocol mips*-*-* PowerPC with DINK32 monitor powerpc{,le}-*-eabi PowerPC with SDS protocol powerpc{,le}-*-eabi Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi * DWARF 2 All configurations can now understand and use the DWARF 2 debugging format. The choice is automatic, if the symbol file contains DWARF 2 information. * Java frontend GDB now includes basic Java language support. This support is only useful with Java compilers that produce native machine code. * solib-absolute-prefix and solib-search-path For SunOS and SVR4 shared libraries, you may now set the prefix for loading absolute shared library symbol files, and the search path for locating non-absolute shared library symbol files. * Live range splitting GDB can now effectively debug code for which GCC has performed live range splitting as part of its optimization. See gdb/doc/LRS for more details on the expected format of the stabs information. * Hurd support GDB's support for the GNU Hurd, including thread debugging, has been updated to work with current versions of the Hurd. * ARM Thumb support GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit instruction set. ARM GDB automatically detects when Thumb instructions are in use, and adjusts disassembly and backtracing accordingly. * MIPS16 support GDB's MIPS target configurations now handle the MIP16 16-bit instruction set. * Overlay support GDB now includes support for overlays; if an executable has been linked such that multiple sections are based at the same address, GDB will decide which section to use for symbolic info. You can choose to control the decision manually, using overlay commands, or implement additional target-side support and use "overlay load-target" to bring in the overlay mapping. Do "help overlay" for more detail. * info symbol The command "info symbol
" displays information about the symbol at the specified address. * Trace support The standard remote protocol now includes an extension that allows asynchronous collection and display of trace data. This requires extensive support in the target-side debugging stub. Tracing mode includes a new interaction mode in GDB and new commands: see the file tracepoint.c for more details. * MIPS simulator Configurations for embedded MIPS now include a simulator contributed by Cygnus Solutions. The simulator supports the instruction sets of most MIPS variants. * Sparc simulator Sparc configurations may now include the ERC32 simulator contributed by the European Space Agency. The simulator is not built into Sparc targets by default; configure with --enable-sim to include it. * set architecture For target configurations that may include multiple variants of a basic architecture (such as MIPS and SH), you may now set the architecture explicitly. "set arch" sets, "info arch" lists the possible architectures. *** Changes in GDB-4.16: * New native configurations Windows 95, x86 Windows NT i[345]86-*-cygwin32 M68K NetBSD m68k-*-netbsd* PowerPC AIX 4.x powerpc-*-aix* PowerPC MacOS powerpc-*-macos* PowerPC Windows NT powerpcle-*-cygwin32 RS/6000 AIX 4.x rs6000-*-aix4* * New targets ARM with RDP protocol arm-*-* I960 with MON960 i960-*-coff MIPS VxWorks mips*-*-vxworks* MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf* PowerPC with PPCBUG monitor powerpc{,le}-*-eabi* Hitachi SH3 sh-*-* Matra Sparclet sparclet-*-* * PowerPC simulator The powerpc-eabi configuration now includes the PSIM simulator, contributed by Andrew Cagney, with assistance from Mike Meissner. PSIM is a very elaborate model of the PowerPC, including not only basic instruction set execution, but also details of execution unit performance and I/O hardware. See sim/ppc/README for more details. * Solaris 2.5 GDB now works with Solaris 2.5. * Windows 95/NT native GDB will now work as a native debugger on Windows 95 and Windows NT. To build it from source, you must use the "gnu-win32" environment, which uses a DLL to emulate enough of Unix to run the GNU tools. Further information, binaries, and sources are available at ftp.cygnus.com, under pub/gnu-win32. * dont-repeat command If a user-defined command includes the command `dont-repeat', then the command will not be repeated if the user just types return. This is useful if the command is time-consuming to run, so that accidental extra keystrokes don't run the same command many times. * Send break instead of ^C The standard remote protocol now includes an option to send a break rather than a ^C to the target in order to interrupt it. By default, GDB will send ^C; to send a break, set the variable `remotebreak' to 1. * Remote protocol timeout The standard remote protocol includes a new variable `remotetimeout' that allows you to set the number of seconds before GDB gives up trying to read from the target. The default value is 2. * Automatic tracking of dynamic object loading (HPUX and Solaris only) By default GDB will automatically keep track of objects as they are loaded and unloaded by the dynamic linker. By using the command `set stop-on-solib-events 1' you can arrange for GDB to stop the inferior when shared library events occur, thus allowing you to set breakpoints in shared libraries which are explicitly loaded by the inferior. Note this feature does not work on hpux8. On hpux9 you must link /usr/lib/end.o into your program. This feature should work automatically on hpux10. * Irix 5.x hardware watchpoint support Irix 5 configurations now support the use of hardware watchpoints. * Mips protocol "SYN garbage limit" When debugging a Mips target using the `target mips' protocol, you may set the number of characters that GDB will ignore by setting the `syn-garbage-limit'. A value of -1 means that GDB will ignore every character. The default value is 1050. * Recording and replaying remote debug sessions If you set `remotelogfile' to the name of a file, gdb will write to it a recording of a remote debug session. This recording may then be replayed back to gdb using "gdbreplay". See gdbserver/README for details. This is useful when you have a problem with GDB while doing remote debugging; you can make a recording of the session and send it to someone else, who can then recreate the problem. * Speedups for remote debugging GDB includes speedups for downloading and stepping MIPS systems using the IDT monitor, fast downloads to the Hitachi SH E7000 emulator, and more efficient S-record downloading. * Memory use reductions and statistics collection GDB now uses less memory and reports statistics about memory usage. Try the `maint print statistics' command, for example. *** Changes in GDB-4.15: * Psymtabs for XCOFF The symbol reader for AIX GDB now uses partial symbol tables. This can greatly improve startup time, especially for large executables. * Remote targets use caching Remote targets now use a data cache to speed up communication with the remote side. The data cache could lead to incorrect results because it doesn't know about volatile variables, thus making it impossible to debug targets which use memory mapped I/O devices. `set remotecache off' turns the the data cache off. * Remote targets may have threads The standard remote protocol now includes support for multiple threads in the target system, using new protocol commands 'H' and 'T'. See gdb/remote.c for details. * NetROM support If GDB is configured with `--enable-netrom', then it will include support for the NetROM ROM emulator from XLNT Designs. The NetROM acts as though it is a bank of ROM on the target board, but you can write into it over the network. GDB's support consists only of support for fast loading into the emulated ROM; to debug, you must use another protocol, such as standard remote protocol. The usual sequence is something like target nrom load target remote :1235 * Macintosh host GDB now includes support for the Apple Macintosh, as a host only. It may be run as either an MPW tool or as a standalone application, and it can debug through the serial port. All the usual GDB commands are available, but to the target command, you must supply "serial" as the device type instead of "/dev/ttyXX". See mpw-README in the main directory for more information on how to build. The MPW configuration scripts */mpw-config.in support only a few targets, and only the mips-idt-ecoff target has been tested. * Autoconf GDB configuration now uses autoconf. This is not user-visible, but does simplify configuration and building. * hpux10 GDB now supports hpux10. *** Changes in GDB-4.14: * New native configurations x86 FreeBSD i[345]86-*-freebsd x86 NetBSD i[345]86-*-netbsd NS32k NetBSD ns32k-*-netbsd Sparc NetBSD sparc-*-netbsd * New targets A29K VxWorks a29k-*-vxworks HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro* CPU32 EST-300 emulator m68*-*-est* PowerPC ELF powerpc-*-elf WDC 65816 w65-*-* * Alpha OSF/1 support for procfs GDB now supports procfs under OSF/1-2.x and higher, which makes it possible to attach to running processes. As the mounting of the /proc filesystem is optional on the Alpha, GDB automatically determines the availability of /proc during startup. This can lead to problems if /proc is unmounted after GDB has been started. * Arguments to user-defined commands User commands may accept up to 10 arguments separated by whitespace. Arguments are accessed within the user command via $arg0..$arg9. A trivial example: define adder print $arg0 + $arg1 + $arg2 To execute the command use: adder 1 2 3 Defines the command "adder" which prints the sum of its three arguments. Note the arguments are text substitutions, so they may reference variables, use complex expressions, or even perform inferior function calls. * New `if' and `while' commands This makes it possible to write more sophisticated user-defined commands. Both commands take a single argument, which is the expression to evaluate, and must be followed by the commands to execute, one per line, if the expression is nonzero, the list being terminated by the word `end'. The `if' command list may include an `else' word, which causes the following commands to be executed only if the expression is zero. * Fortran source language mode GDB now includes partial support for Fortran 77. It will recognize Fortran programs and can evaluate a subset of Fortran expressions, but variables and functions may not be handled correctly. GDB will work with G77, but does not yet know much about symbols emitted by other Fortran compilers. * Better HPUX support Most debugging facilities now work on dynamic executables for HPPAs running hpux9 or later. You can attach to running dynamically linked processes, but by default the dynamic libraries will be read-only, so for instance you won't be able to put breakpoints in them. To change that behavior do the following before running the program: adb -w a.out __dld_flags?W 0x5 control-d This will cause the libraries to be mapped private and read-write. To revert to the normal behavior, do this: adb -w a.out __dld_flags?W 0x4 control-d You cannot set breakpoints or examine data in the library until after the library is loaded if the function/data symbols do not have external linkage. GDB can now also read debug symbols produced by the HP C compiler on HPPAs (sorry, no C++, Fortran or 68k support). * Target byte order now dynamically selectable You can choose which byte order to use with a target system, via the commands "set endian big" and "set endian little", and you can see the current setting by using "show endian". You can also give the command "set endian auto", in which case GDB will use the byte order associated with the executable. Currently, only embedded MIPS configurations support dynamic selection of target byte order. * New DOS host serial code This version uses DPMI interrupts to handle buffered I/O, so you no longer need to run asynctsr when debugging boards connected to a PC's serial port. *** Changes in GDB-4.13: * New "complete" command This lists all the possible completions for the rest of the line, if it were to be given as a command itself. This is intended for use by emacs. * Trailing space optional in prompt "set prompt" no longer adds a space for you after the prompt you set. This allows you to set a prompt which ends in a space or one that does not. * Breakpoint hit counts "info break" now displays a count of the number of times the breakpoint has been hit. This is especially useful in conjunction with "ignore"; you can ignore a large number of breakpoint hits, look at the breakpoint info to see how many times the breakpoint was hit, then run again, ignoring one less than that number, and this will get you quickly to the last hit of that breakpoint. * Ability to stop printing at NULL character "set print null-stop" will cause GDB to stop printing the characters of an array when the first NULL is encountered. This is useful when large arrays actually contain only short strings. * Shared library breakpoints In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set breakpoints in shared libraries before the executable is run. * Hardware watchpoints There is a new hardware breakpoint for the watch command for sparclite targets. See gdb/sparclite/hw_breakpoint.note. Hardware watchpoints are also now supported under GNU/Linux. * Annotations Annotations have been added. These are for use with graphical interfaces, and are still experimental. Currently only gdba.el uses these. * Improved Irix 5 support GDB now works properly with Irix 5.2. * Improved HPPA support GDB now works properly with the latest GCC and GAS. * New native configurations Sequent PTX4 i[34]86-sequent-ptx4 HPPA running OSF/1 hppa*-*-osf* Atari TT running SVR4 m68*-*-sysv4* RS/6000 LynxOS rs6000-*-lynxos* * New targets OS/9000 i[34]86-*-os9k MIPS R4000 mips64*{,el}-*-{ecoff,elf} Sparc64 sparc64-*-* * Hitachi SH7000 and E7000-PC ICE support There is now support for communicating with the Hitachi E7000-PC ICE. This is available automatically when GDB is configured for the SH. * Fixes As usual, a variety of small fixes and improvements, both generic and configuration-specific. See the ChangeLog for more detail. *** Changes in GDB-4.12: * Irix 5 is now supported * HPPA support GDB-4.12 on the HPPA has a number of changes which make it unable to debug the output from the currently released versions of GCC and GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release of GCC and GAS, versions of these tools designed to work with GDB-4.12 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist. *** Changes in GDB-4.11: * User visible changes: * Remote Debugging The "set remotedebug" option is now consistent between the mips remote target, remote targets using the gdb-specific protocol, UDI (AMD's debug protocol for the 29k) and the 88k bug monitor. It is now an integer specifying a debug level (normally 0 or 1, but 2 means more debugging info for the mips target). * DEC Alpha native support GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable debug info, but GDB works fairly well with the DEC compiler and should work with a future GCC release. See the README file for a few Alpha-specific notes. * Preliminary thread implementation GDB now has preliminary thread support for both SGI/Irix and LynxOS. * LynxOS native and target support for 386 This release has been hosted on LynxOS 2.2, and also can be configured to remotely debug programs running under LynxOS (see gdb/gdbserver/README for details). * Improvements in C++ mangling/demangling. This release has much better g++ debugging, specifically in name mangling/demangling, virtual function calls, print virtual table, call methods, ...etc. *** Changes in GDB-4.10: * User visible changes: Remote debugging using the GDB-specific (`target remote') protocol now supports the `load' command. This is only useful if you have some other way of getting the stub to the target system, and you can put it somewhere in memory where it won't get clobbered by the download. Filename completion now works. When run under emacs mode, the "info line" command now causes the arrow to point to the line specified. Also, "info line" prints addresses in symbolic form (as well as hex). All vxworks based targets now support a user settable option, called vxworks-timeout. This option represents the number of seconds gdb should wait for responses to rpc's. You might want to use this if your vxworks target is, perhaps, a slow software simulator or happens to be on the far side of a thin network line. * DEC alpha support This release contains support for using a DEC alpha as a GDB host for cross debugging. Native alpha debugging is not supported yet. *** Changes in GDB-4.9: * Testsuite This is the first GDB release which is accompanied by a matching testsuite. The testsuite requires installation of dejagnu, which should be available via ftp from most sites that carry GNU software. * C++ demangling 'Cfront' style demangling has had its name changed to 'ARM' style, to emphasize that it was written from the specifications in the C++ Annotated Reference Manual, not necessarily to be compatible with AT&T cfront. Despite disclaimers, it still generated too much confusion with users attempting to use gdb with AT&T cfront. * Simulators GDB now uses a standard remote interface to a simulator library. So far, the library contains simulators for the Zilog Z8001/2, the Hitachi H8/300, H8/500 and Super-H. * New targets supported H8/300 simulator h8300-hitachi-hms or h8300hms H8/500 simulator h8500-hitachi-hms or h8500hms SH simulator sh-hitachi-hms or sh Z8000 simulator z8k-zilog-none or z8ksim IDT MIPS board over serial line mips-idt-ecoff Cross-debugging to GO32 targets is supported. It requires a custom version of the i386-stub.c module which is integrated with the GO32 memory extender. * New remote protocols MIPS remote debugging protocol. * New source languages supported This version includes preliminary support for Chill, a Pascal like language used by telecommunications companies. Chill support is also being integrated into the GNU compiler, but we don't know when it will be publically available. *** Changes in GDB-4.8: * HP Precision Architecture supported GDB now supports HP PA-RISC machines running HPUX. A preliminary version of this support was available as a set of patches from the University of Utah. GDB does not support debugging of programs compiled with the HP compiler, because HP will not document their file format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z). Many problems in the preliminary version have been fixed. * Faster and better demangling We have improved template demangling and fixed numerous bugs in the GNU style demangler. It can now handle type modifiers such as `static' or `const'. Wide character types (wchar_t) are now supported. Demangling of each symbol is now only done once, and is cached when the symbol table for a file is read in. This results in a small increase in memory usage for C programs, a moderate increase in memory usage for C++ programs, and a fantastic speedup in symbol lookups. `Cfront' style demangling still doesn't work with AT&T cfront. It was written from the specifications in the Annotated Reference Manual, which AT&T's compiler does not actually implement. * G++ multiple inheritance compiler problem In the 2.3.2 release of gcc/g++, how the compiler resolves multiple inheritance lattices was reworked to properly discover ambiguities. We recently found an example which causes this new algorithm to fail in a very subtle way, producing bad debug information for those classes. The file 'gcc.patch' (in this directory) can be applied to gcc to circumvent the problem. A future GCC release will contain a complete fix. The previous G++ debug info problem (mentioned below for the gdb-4.7 release) is fixed in gcc version 2.3.2. * Improved configure script The `configure' script will now attempt to guess your system type if you don't supply a host system type. The old scheme of supplying a host system triplet is preferable over using this. All the magic is done in the new `config.guess' script. Examine it for details. We have also brought our configure script much more in line with the FSF's version. It now supports the --with-xxx options. In particular, `--with-minimal-bfd' can be used to make the GDB binary image smaller. The resulting GDB will not be able to read arbitrary object file formats -- only the format ``expected'' to be used on the configured target system. We hope to make this the default in a future release. * Documentation improvements There's new internal documentation on how to modify GDB, and how to produce clean changes to the code. We implore people to read it before submitting changes. The GDB manual uses new, sexy Texinfo conditionals, rather than arcane M4 macros. The new texinfo.tex is provided in this release. Pre-built `info' files are also provided. To build `info' files from scratch, you will need the latest `makeinfo' release, which will be available in a future texinfo-X.Y release. *NOTE* The new texinfo.tex can cause old versions of TeX to hang. We're not sure exactly which versions have this problem, but it has been seen in 3.0. We highly recommend upgrading to TeX version 3.141 or better. If that isn't possible, there is a patch in `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work around this problem. * New features GDB now supports array constants that can be used in expressions typed in by the user. The syntax is `{element, element, ...}'. Ie: you can now type `print {1, 2, 3}', and it will build up an array in memory malloc'd in the target program. The new directory `gdb/sparclite' contains a program that demonstrates how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor. * New native hosts supported HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4 * New targets supported AMD 29k family via UDI a29k-amd-udi or udi29k * New file formats supported BFD now supports reading HP/PA-RISC executables (SOM file format?), HPUX core files, and SCO 3.2v2 core files. * Major bug fixes Attaching to processes now works again; thanks for the many bug reports. We have also stomped on a bunch of core dumps caused by printf_filtered("%s") problems. We eliminated a copyright problem on the rpc and ptrace header files for VxWorks, which was discovered at the last minute during the 4.7 release. You should now be able to build a VxWorks GDB. You can now interrupt gdb while an attached process is running. This will cause the attached process to stop, and give control back to GDB. We fixed problems caused by using too many file descriptors for reading symbols from object files and libraries. This was especially a problem for programs that used many (~100) shared libraries. The `step' command now only enters a subroutine if there is line number information for the subroutine. Otherwise it acts like the `next' command. Previously, `step' would enter subroutines if there was any debugging information about the routine. This avoids problems when using `cc -g1' on MIPS machines. * Internal improvements GDB's internal interfaces have been improved to make it easier to support debugging of multiple languages in the future. GDB now uses a common structure for symbol information internally. Minimal symbols (derived from linkage symbols in object files), partial symbols (from a quick scan of debug information), and full symbols contain a common subset of information, making it easier to write shared code that handles any of them. * New command line options We now accept --silent as an alias for --quiet. * Mmalloc licensing The memory-mapped-malloc library is now licensed under the GNU Library General Public License. *** Changes in GDB-4.7: * Host/native/target split GDB has had some major internal surgery to untangle the support for hosts and remote targets. Now, when you configure GDB for a remote target, it will no longer load in all of the support for debugging local programs on the host. When fully completed and tested, this will ensure that arbitrary host/target combinations are possible. The primary conceptual shift is to separate the non-portable code in GDB into three categories. Host specific code is required any time GDB is compiled on that host, regardless of the target. Target specific code relates to the peculiarities of the target, but can be compiled on any host. Native specific code is everything else: it can only be built when the host and target are the same system. Child process handling and core file support are two common `native' examples. GDB's use of /proc for controlling Unix child processes is now cleaner. It has been split out into a single module under the `target_ops' vector, plus two native-dependent functions for each system that uses /proc. * New hosts supported HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco * New targets supported Fujitsu SPARClite sparclite-fujitsu-none or sparclite 68030 and CPU32 m68030-*-*, m68332-*-* * New native hosts supported 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd (386bsd is not well tested yet) 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco * New file formats supported BFD now supports COFF files for the Zilog Z8000 microprocessor. It supports reading of `a.out.adobe' object files, which are an a.out format extended with minimal information about multiple sections. * New commands `show copying' is the same as the old `info copying'. `show warranty' is the same as `info warrantee'. These were renamed for consistency. The old commands continue to work. `info handle' is a new alias for `info signals'. You can now define pre-command hooks, which attach arbitrary command scripts to any command. The commands in the hook will be executed prior to the user's command. You can also create a hook which will be executed whenever the program stops. See gdb.texinfo. * C++ improvements We now deal with Cfront style name mangling, and can even extract type info from mangled symbols. GDB can automatically figure out which symbol mangling style your C++ compiler uses. Calling of methods and virtual functions has been improved as well. * Major bug fixes The crash that occured when debugging Sun Ansi-C compiled binaries is fixed. This was due to mishandling of the extra N_SO stabs output by the compiler. We also finally got Ultrix 4.2 running in house, and fixed core file support, with help from a dozen people on the net. John M. Farrell discovered that the reason that single-stepping was so slow on all of the Mips based platforms (primarily SGI and DEC) was that we were trying to demangle and lookup a symbol used for internal purposes on every instruction that was being stepped through. Changing the name of that symbol so that it couldn't be mistaken for a C++ mangled symbol sped things up a great deal. Rich Pixley sped up symbol lookups in general by getting much smarter about when C++ symbol mangling is necessary. This should make symbol completion (TAB on the command line) much faster. It's not as fast as we'd like, but it's significantly faster than gdb-4.6. * AMD 29k support A new user controllable variable 'call_scratch_address' can specify the location of a scratch area to be used when GDB calls a function in the target. This is necessary because the usual method of putting the scratch area on the stack does not work in systems that have separate instruction and data spaces. We integrated changes to support the 29k UDI (Universal Debugger Interface), but discovered at the last minute that we didn't have all of the appropriate copyright paperwork. We are working with AMD to resolve this, and hope to have it available soon. * Remote interfaces We have sped up the remote serial line protocol, especially for targets with lots of registers. It now supports a new `expedited status' ('T') message which can be used in place of the existing 'S' status message. This allows the remote stub to send only the registers that GDB needs to make a quick decision about single-stepping or conditional breakpoints, eliminating the need to fetch the entire register set for each instruction being stepped through. The GDB remote serial protocol now implements a write-through cache for registers, only re-reading the registers if the target has run. There is also a new remote serial stub for SPARC processors. You can find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the Fujitsu SPARClite processor, but will run on any stand-alone SPARC processor with a serial port. * Configuration Configure.in files have become much easier to read and modify. A new `table driven' format makes it more obvious what configurations are supported, and what files each one uses. * Library changes There is a new opcodes library which will eventually contain all of the disassembly routines and opcode tables. At present, it only contains Sparc and Z8000 routines. This will allow the assembler, debugger, and disassembler (binutils/objdump) to share these routines. The libiberty library is now copylefted under the GNU Library General Public License. This allows more liberal use, and was done so libg++ can use it. This makes no difference to GDB, since the Library License grants all the rights from the General Public License. * Documentation The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete reference to the stabs symbol info used by the debugger. It is (as far as we know) the only published document on this fascinating topic. We encourage you to read it, compare it to the stabs information on your system, and send improvements on the document in general (to bug-gdb@prep.ai.mit.edu). And, of course, many bugs have been fixed. *** Changes in GDB-4.6: * Better support for C++ function names GDB now accepts as input the "demangled form" of C++ overloaded function names and member function names, and can do command completion on such names (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'. Make use of command completion, it is your friend. GDB also now accepts a variety of C++ mangled symbol formats. They are the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style. You can tell GDB which format to use by doing a 'set demangle-style {gnu, lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo' for the list of formats. * G++ symbol mangling problem Recent versions of gcc have a bug in how they emit debugging information for C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this directory) can be applied to gcc to fix the problem. Alternatively, if you can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The usual symptom is difficulty with setting breakpoints on methods. GDB complains about the method being non-existent. (We believe that version 2.2.2 of GCC has this problem.) * New 'maintenance' command All of the commands related to hacking GDB internals have been moved out of the main command set, and now live behind the 'maintenance' command. This can also be abbreviated as 'mt'. The following changes were made: dump-me -> maintenance dump-me info all-breakpoints -> maintenance info breakpoints printmsyms -> maintenance print msyms printobjfiles -> maintenance print objfiles printpsyms -> maintenance print psymbols printsyms -> maintenance print symbols The following commands are new: maintenance demangle Call internal GDB demangler routine to demangle a C++ link name and prints the result. maintenance print type Print a type chain for a given symbol * Change to .gdbinit file processing We now read the $HOME/.gdbinit file before processing the argv arguments (e.g. reading symbol files or core files). This allows global parameters to be set, which will apply during the symbol reading. The ./.gdbinit is still read after argv processing. * New hosts supported Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2 GNU/Linux support i386-unknown-linux or linux We are also including code to support the HP/PA running BSD and HPUX. This is almost guaranteed not to work, as we didn't have time to test or build it for this release. We are including it so that the more adventurous (or masochistic) of you can play with it. We also had major problems with the fact that the compiler that we got from HP doesn't support the -g option. It costs extra. * New targets supported Hitachi H8/300 h8300-hitachi-hms or h8300hms * More smarts about finding #include files GDB now remembers the compilation directory for all include files, and for all files from which C is generated (like yacc and lex sources). This greatly improves GDB's ability to find yacc/lex sources, and include files, especially if you are debugging your program from a directory different from the one that contains your sources. We also fixed a bug which caused difficulty with listing and setting breakpoints in include files which contain C code. (In the past, you had to try twice in order to list an include file that you hadn't looked at before.) * Interesting infernals change GDB now deals with arbitrary numbers of sections, where the symbols for each section must be relocated relative to that section's landing place in the target's address space. This work was needed to support ELF with embedded stabs used by Solaris-2.0. * Bug fixes (of course!) There have been loads of fixes for the following things: mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k, i960, stabs, DOS(GO32), procfs, etc... See the ChangeLog for details. *** Changes in GDB-4.5: * New machines supported (host and target) IBM RS6000 running AIX rs6000-ibm-aix or rs6000 SGI Irix-4.x mips-sgi-irix4 or iris4 * New malloc package GDB now uses a new memory manager called mmalloc, based on gmalloc. Mmalloc is capable of handling mutiple heaps of memory. It is also capable of saving a heap to a file, and then mapping it back in later. This can be used to greatly speedup the startup of GDB by using a pre-parsed symbol table which lives in a mmalloc managed heap. For more details, please read mmalloc/mmalloc.texi. * info proc The 'info proc' command (SVR4 only) has been enhanced quite a bit. See 'help info proc' for details. * MIPS ecoff symbol table format The code that reads MIPS symbol table format is now supported on all hosts. Thanks to MIPS for releasing the sym.h and symconst.h files to make this possible. * File name changes for MS-DOS Many files in the config directories have been renamed to make it easier to support GDB on MS-DOSe systems (which have very restrictive file name conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32 environment) is close to working but has some remaining problems. Note that debugging of DOS programs is not supported, due to limitations in the ``operating system'', but it can be used to host cross-debugging. * Cross byte order fixes Many fixes have been made to support cross debugging of Sparc and MIPS targets from hosts whose byte order differs. * New -mapped and -readnow options If memory-mapped files are available on your system through the 'mmap' system call, you can use the -mapped option on the `file' or `symbol-file' commands to cause GDB to write the symbols from your program into a reusable file. If the program you are debugging is called `/path/fred', the mapped symbol file will be `./fred.syms'. Future GDB debugging sessions will notice the presence of this file, and will quickly map in symbol information from it, rather than reading the symbol table from the executable program. Using the '-mapped' option in a GDB `file' or `symbol-file' command has the same effect as starting GDB with the '-mapped' command-line option. You can cause GDB to read the entire symbol table immediately by using the '-readnow' option with any of the commands that load symbol table information (or on the GDB command line). This makes the command slower, but makes future operations faster. The -mapped and -readnow options are typically combined in order to build a `fred.syms' file that contains complete symbol information. A simple GDB invocation to do nothing but build a `.syms' file for future use is: gdb -batch -nx -mapped -readnow programname The `.syms' file is specific to the host machine on which GDB is run. It holds an exact image of GDB's internal symbol table. It cannot be shared across multiple host platforms. * longjmp() handling GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and siglongjmp() without losing control. This feature has not yet been ported to all systems. It currently works on many 386 platforms, all MIPS-based platforms (SGI, DECstation, etc), and Sun3/4. * Solaris 2.0 Preliminary work has been put in to support the new Solaris OS from Sun. At this time, it can control and debug processes, but it is not capable of reading symbols. * Bug fixes As always, many many bug fixes. The major areas were with g++, and mipsread. People using the MIPS-based platforms should experience fewer mysterious crashes and trashed symbol tables. *** Changes in GDB-4.4: * New machines supported (host and target) SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco (except core files) BSD Reno on Vax vax-dec-bsd Ultrix on Vax vax-dec-ultrix * New machines supported (target) AMD 29000 embedded, using EBMON a29k-none-none * C++ support GDB continues to improve its handling of C++. `References' work better. The demangler has also been improved, and now deals with symbols mangled as per the Annotated C++ Reference Guide. GDB also now handles `stabs' symbol information embedded in MIPS `ecoff' symbol tables. Since the ecoff format was not easily extensible to handle new languages such as C++, this appeared to be a good way to put C++ debugging info into MIPS binaries. This option will be supported in the GNU C compiler, version 2, when it is released. * New features for SVR4 GDB now handles SVR4 shared libraries, in the same fashion as SunOS shared libraries. Debugging dynamically linked programs should present only minor differences from debugging statically linked programs. The `info proc' command will print out information about any process on an SVR4 system (including the one you are debugging). At the moment, it prints the address mappings of the process. If you bring up GDB on another SVR4 system, please send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any). * Better dynamic linking support in SunOS Reading symbols from shared libraries which contain debugging symbols now works properly. However, there remain issues such as automatic skipping of `transfer vector' code during function calls, which make it harder to debug code in a shared library, than to debug the same code linked statically. * New Getopt GDB is now using the latest `getopt' routines from the FSF. This version accepts the -- prefix for options with long names. GDB will continue to accept the old forms (-option and +option) as well. Various single letter abbreviations for options have been explicity added to the option table so that they won't get overshadowed in the future by other options that begin with the same letter. * Bugs fixed The `cleanup_undefined_types' bug that many of you noticed has been squashed. Many assorted bugs have been handled. Many more remain to be handled. See the various ChangeLog files (primarily in gdb and bfd) for details. *** Changes in GDB-4.3: * New machines supported (host and target) Amiga 3000 running Amix m68k-cbm-svr4 or amix NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88 * Almost SCO Unix support We had hoped to support: SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco (except for core file support), but we discovered very late in the release that it has problems with process groups that render gdb unusable. Sorry about that. I encourage people to fix it and post the fixes. * Preliminary ELF and DWARF support GDB can read ELF object files on System V Release 4, and can handle debugging records for C, in DWARF format, in ELF files. This support is preliminary. If you bring up GDB on another SVR4 system, please send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any). * New Readline GDB now uses the latest `readline' library. One user-visible change is that two tabs will list possible command completions, which previously required typing M-? (meta-question mark, or ESC ?). * Bugs fixed The `stepi' bug that many of you noticed has been squashed. Many bugs in C++ have been handled. Many more remain to be handled. See the various ChangeLog files (primarily in gdb and bfd) for details. * State of the MIPS world (in case you wondered): GDB can understand the symbol tables emitted by the compilers supplied by most vendors of MIPS-based machines, including DEC. These symbol tables are in a format that essentially nobody else uses. Some versions of gcc come with an assembler post-processor called mips-tfile. This program is required if you want to do source-level debugging of gcc-compiled programs. I believe FSF does not ship mips-tfile with gcc version 1, but it will eventually come with gcc version 2. Debugging of g++ output remains a problem. g++ version 1.xx does not really support it at all. (If you're lucky, you should be able to get line numbers and stack traces to work, but no parameters or local variables.) With some work it should be possible to improve the situation somewhat. When gcc version 2 is released, you will have somewhat better luck. However, even then you will get confusing results for inheritance and methods. We will eventually provide full debugging of g++ output on DECstations. This will probably involve some kind of stabs-in-ecoff encapulation, but the details have not been worked out yet. *** Changes in GDB-4.2: * Improved configuration Only one copy of `configure' exists now, and it is not self-modifying. Porting BFD is simpler. * Stepping improved The `step' and `next' commands now only stop at the first instruction of a source line. This prevents the multiple stops that used to occur in switch statements, for-loops, etc. `Step' continues to stop if a function that has debugging information is called within the line. * Bug fixing Lots of small bugs fixed. More remain. * New host supported (not target) Intel 386 PC clone running Mach i386-none-mach *** Changes in GDB-4.1: * Multiple source language support GDB now has internal scaffolding to handle several source languages. It determines the type of each source file from its filename extension, and will switch expression parsing and number formatting to match the language of the function in the currently selected stack frame. You can also specifically set the language to be used, with `set language c' or `set language modula-2'. * GDB and Modula-2 GDB now has preliminary support for the GNU Modula-2 compiler, currently under development at the State University of New York at Buffalo. Development of both GDB and the GNU Modula-2 compiler will continue through the fall of 1991 and into 1992. Other Modula-2 compilers are currently not supported, and attempting to debug programs compiled with them will likely result in an error as the symbol table is read. Feel free to work on it, though! There are hooks in GDB for strict type checking and range checking, in the `Modula-2 philosophy', but they do not currently work. * set write on/off GDB can now write to executable and core files (e.g. patch a variable's value). You must turn this switch on, specify the file ("exec foo" or "core foo"), *then* modify it, e.g. by assigning a new value to a variable. Modifications take effect immediately. * Automatic SunOS shared library reading When you run your program, GDB automatically determines where its shared libraries (if any) have been loaded, and reads their symbols. The `share' command is no longer needed. This also works when examining core files. * set listsize You can specify the number of lines that the `list' command shows. The default is 10. * New machines supported (host and target) SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3 * New hosts supported (not targets) IBM RT/PC: romp-ibm-aix or rtpc * New targets supported (not hosts) AMD 29000 embedded with COFF a29k-none-coff AMD 29000 embedded with a.out a29k-none-aout Ultracomputer remote kernel debug a29k-nyu-kern * New remote interfaces AMD 29000 Adapt AMD 29000 Minimon *** Changes in GDB-4.0: * New Facilities Wide output is wrapped at good places to make the output more readable. Gdb now supports cross-debugging from a host machine of one type to a target machine of another type. Communication with the target system is over serial lines. The ``target'' command handles connecting to the remote system; the ``load'' command will download a program into the remote system. Serial stubs for the m68k and i386 are provided. Gdb also supports debugging of realtime processes running under VxWorks, using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger stub on the target system. New CPUs supported include the AMD 29000 and Intel 960. GDB now reads object files and symbol tables via a ``binary file'' library, which allows a single copy of GDB to debug programs of multiple object file types such as a.out and coff. There is now a GDB reference card in "doc/refcard.tex". (Make targets refcard.dvi and refcard.ps are available to format it). * Control-Variable user interface simplified All variables that control the operation of the debugger can be set by the ``set'' command, and displayed by the ``show'' command. For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>. ``Show prompt'' produces the response: Gdb's prompt is new-gdb=>. What follows are the NEW set commands. The command ``help set'' will print a complete list of old and new set commands. ``help set FOO'' will give a longer description of the variable FOO. ``show'' will show all of the variable descriptions and their current settings. confirm on/off: Enables warning questions for operations that are hard to recover from, e.g. rerunning the program while it is already running. Default is ON. editing on/off: Enables EMACS style command line editing of input. Previous lines can be recalled with control-P, the current line can be edited with control-B, you can search for commands with control-R, etc. Default is ON. history filename NAME: NAME is where the gdb command history will be stored. The default is .gdb_history, or the value of the environment variable GDBHISTFILE. history size N: The size, in commands, of the command history. The default is 256, or the value of the environment variable HISTSIZE. history save on/off: If this value is set to ON, the history file will be saved after exiting gdb. If set to OFF, the file will not be saved. The default is OFF. history expansion on/off: If this value is set to ON, then csh-like history expansion will be performed on command line input. The default is OFF. radix N: Sets the default radix for input and output. It can be set to 8, 10, or 16. Note that the argument to "radix" is interpreted in the current radix, so "set radix 10" is always a no-op. height N: This integer value is the number of lines on a page. Default is 24, the current `stty rows'' setting, or the ``li#'' setting from the termcap entry matching the environment variable TERM. width N: This integer value is the number of characters on a line. Default is 80, the current `stty cols'' setting, or the ``co#'' setting from the termcap entry matching the environment variable TERM. Note: ``set screensize'' is obsolete. Use ``set height'' and ``set width'' instead. print address on/off: Print memory addresses in various command displays, such as stack traces and structure values. Gdb looks more ``symbolic'' if you turn this off; it looks more ``machine level'' with it on. Default is ON. print array on/off: Prettyprint arrays. New convenient format! Default is OFF. print demangle on/off: Print C++ symbols in "source" form if on, "raw" form if off. print asm-demangle on/off: Same, for assembler level printouts like instructions. print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF. * Support for Epoch Environment. The epoch environment is a version of Emacs v18 with windowing. One new command, ``inspect'', is identical to ``print'', except that if you are running in the epoch environment, the value is printed in its own window. * Support for Shared Libraries GDB can now debug programs and core files that use SunOS shared libraries. Symbols from a shared library cannot be referenced before the shared library has been linked with the program (this happens after you type ``run'' and before the function main() is entered). At any time after this linking (including when examining core files from dynamically linked programs), gdb reads the symbols from each shared library when you type the ``sharedlibrary'' command. It can be abbreviated ``share''. sharedlibrary REGEXP: Load shared object library symbols for files matching a unix regular expression. No argument indicates to load symbols for all shared libraries. info sharedlibrary: Status of loaded shared libraries. * Watchpoints A watchpoint stops execution of a program whenever the value of an expression changes. Checking for this slows down execution tremendously whenever you are in the scope of the expression, but is quite useful for catching tough ``bit-spreader'' or pointer misuse problems. Some machines such as the 386 have hardware for doing this more quickly, and future versions of gdb will use this hardware. watch EXP: Set a watchpoint (breakpoint) for an expression. info watchpoints: Information about your watchpoints. delete N: Deletes watchpoint number N (same as breakpoints). disable N: Temporarily turns off watchpoint number N (same as breakpoints). enable N: Re-enables watchpoint number N (same as breakpoints). * C++ multiple inheritance When used with a GCC version 2 compiler, GDB supports multiple inheritance for C++ programs. * C++ exception handling Gdb now supports limited C++ exception handling. Besides the existing ability to breakpoint on an exception handler, gdb can breakpoint on the raising of an exception (before the stack is peeled back to the handler's context). catch FOO: If there is a FOO exception handler in the dynamic scope, set a breakpoint to catch exceptions which may be raised there. Multiple exceptions (``catch foo bar baz'') may be caught. info catch: Lists all exceptions which may be caught in the current stack frame. * Minor command changes The command ``call func (arg, arg, ...)'' now acts like the print command, except it does not print or save a value if the function's result is void. This is similar to dbx usage. The ``up'' and ``down'' commands now always print the frame they end up at; ``up-silently'' and `down-silently'' can be used in scripts to change frames without printing. * New directory command 'dir' now adds directories to the FRONT of the source search path. The path starts off empty. Source files that contain debug information about the directory in which they were compiled can be found even with an empty path; Sun CC and GCC include this information. If GDB can't find your source file in the current directory, type "dir .". * Configuring GDB for compilation For normal use, type ``./configure host''. See README or gdb.texinfo for more details. GDB now handles cross debugging. If you are remotely debugging between two different machines, type ``./configure host -target=targ''. Host is the machine where GDB will run; targ is the machine where the program that you are debugging will run.