What has changed in GDB? (Organized release by release) *** Changes since GDB 7.0 * New targets Xilinx MicroBlaze microblaze-*-* * New Simulators Xilinx MicroBlaze microblaze * Multi-program debugging. GDB now has support for multi-program (a.k.a. multi-executable or multi-exec) debugging. This allows for debugging multiple inferiors simultaneously each running a different program under the same GDB session. See "Debugging Multiple Inferiors and Programs" in the manual for more information. This implied some user visible changes in the multi-inferior support. For example, "info inferiors" now lists inferiors that are not running yet or that have exited already. See also "New commands" and "New options" below. * Changed commands disassemble The disassemble command, when invoked with two arguments, now requires the arguments to be comma-separated. * New commands (for set/show, see "New options" below) record save [] Save a file (in core file format) containing the process record execution log for replay debugging at a later time. record restore Restore the process record execution log that was saved at an earlier time, for replay debugging. add-inferior [-copies ] [-exec ] Add a new inferior. clone-inferior [-copies ] [ID] Make a new inferior ready to execute the same program another inferior has loaded. remove-inferior ID Remove an inferior. maint info program-spaces List the program spaces loaded into GDB. set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g] show remote interrupt-sequence Allow the user to select one of ^C, a BREAK signal or BREAK-g as the sequence to the remote target in order to interrupt the execution. Ctrl-C is a default. Some system prefers BREAK which is high level of serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a Magic SysRq g. It is BREAK signal and character 'g'. set remote interrupt-on-connect [on | off] show remote interrupt-on-connect When interrupt-on-connect is ON, gdb sends interrupt-sequence to remote target when gdb connects to it. This is needed when you debug Linux kernel. set remotebreak [on | off] show remotebreak Deprecated. Use "set/show remote interrupt-sequence" instead. * New options set follow-exec-mode new|same show follow-exec-mode Control whether GDB reuses the same inferior across an exec call or creates a new one. This is useful to be able to restart the old executable after the inferior having done an exec call. *** Changes in GDB 7.0 * GDB now has an interface for JIT compilation. Applications that dynamically generate code can create symbol files in memory and register them with GDB. For users, the feature should work transparently, and for JIT developers, the interface is documented in the GDB manual in the "JIT Compilation Interface" chapter. * Tracepoints may now be conditional. The syntax is as for breakpoints; either an "if" clause appended to the "trace" command, or the "condition" command is available. GDB sends the condition to the target for evaluation using the same bytecode format as is used for tracepoint actions. * "disassemble" command with a /r modifier, print the raw instructions in hex as well as in symbolic form." * Process record and replay In a architecture environment that supports ``process record and replay'', ``process record and replay'' target can record a log of the process execution, and replay it with both forward and reverse execute commands. * Reverse debugging: GDB now has new commands reverse-continue, reverse- step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and set execution-direction {forward|reverse}, for targets that support reverse execution. * GDB now supports hardware watchpoints on MIPS/Linux systems. This feature is available with a native GDB running on kernel version 2.6.28 or later. * GDB now has support for multi-byte and wide character sets on the target. Strings whose character type is wchar_t, char16_t, or char32_t are now correctly printed. GDB supports wide- and unicode- literals in C, that is, L'x', L"string", u'x', u"string", U'x', and U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in `printf'. This feature requires iconv to work properly; if your system does not have a working iconv, GDB can use GNU libiconv. See the installation instructions for more information. * GDB now supports automatic retrieval of shared library files from remote targets. To use this feature, specify a system root that begins with the `remote:' prefix, either via the `set sysroot' command or via the `--with-sysroot' configure-time option. * "info sharedlibrary" now takes an optional regex of libraries to show, and it now reports if a shared library has no debugging information. * Commands `set debug-file-directory', `set solib-search-path' and `set args' now complete on file names. * When completing in expressions, gdb will attempt to limit completions to allowable structure or union fields, where appropriate. For instance, consider: # struct example { int f1; double f2; }; # struct example variable; (gdb) p variable. If the user types TAB at the end of this command line, the available completions will be "f1" and "f2". * Inlined functions are now supported. They show up in backtraces, and the "step", "next", and "finish" commands handle them automatically. * GDB now supports the token-splicing (##) and stringification (#) operators when expanding macros. It also supports variable-arity macros. * GDB now supports inspecting extra signal information, exported by the new $_siginfo convenience variable. The feature is currently implemented on linux ARM, i386 and amd64. * GDB can now display the VFP floating point registers and NEON vector registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver can provide these registers (requires Linux 2.6.30 or later). Remote and simulator targets may also provide them. * New remote packets qSearch:memory: Search memory for a sequence of bytes. QStartNoAckMode Turn off `+'/`-' protocol acknowledgments to permit more efficient operation over reliable transport links. Use of this packet is controlled by the `set remote noack-packet' command. vKill Kill the process with the specified process ID. Use this in preference to `k' when multiprocess protocol extensions are supported. qXfer:osdata:read Obtains additional operating system information qXfer:siginfo:read qXfer:siginfo:write Read or write additional signal information. * Removed remote protocol undocumented extension An undocumented extension to the remote protocol's `S' stop reply packet that permited the stub to pass a process id was removed. Remote servers should use the `T' stop reply packet instead. * The "disassemble" command now supports an optional /m modifier to print mixed source+assembly. * GDB now supports multiple function calling conventions according to the DWARF-2 DW_AT_calling_convention function attribute. * The SH target utilizes the aforementioned change to distinguish between gcc and Renesas calling convention. It also adds the new CLI commands `set/show sh calling-convention'. * GDB can now read compressed debug sections, as produced by GNU gold with the --compress-debug-sections=zlib flag. * 64-bit core files are now supported on AIX. * Thread switching is now supported on Tru64. * Watchpoints can now be set on unreadable memory locations, e.g. addresses which will be allocated using malloc later in program execution. * The qXfer:libraries:read remote procotol packet now allows passing a list of section offsets. * On GNU/Linux, GDB can now attach to stopped processes. Several race conditions handling signals delivered during attach or thread creation have also been fixed. * GDB now supports the use of DWARF boolean types for Ada's type Boolean. From the user's standpoint, all unqualified instances of True and False are treated as the standard definitions, regardless of context. * GDB now parses C++ symbol and type names more flexibly. For example, given: template class C { }; C c; GDB will now correctly handle all of: ptype C ptype C ptype C ptype C * New features in the GDB remote stub, gdbserver - The "--wrapper" command-line argument tells gdbserver to use a wrapper program to launch programs for debugging. - On PowerPC and S/390 targets, it is now possible to use a single gdbserver executable to debug both 32-bit and 64-bit programs. (This requires gdbserver itself to be built as a 64-bit executable.) - gdbserver uses the new noack protocol mode for TCP connections to reduce communications latency, if also supported and enabled in GDB. - Support for the sparc64-linux-gnu target is now included in gdbserver. - The amd64-linux build of gdbserver now supports debugging both 32-bit and 64-bit programs. - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver now support hardware watchpoints, and will use them automatically as appropriate. * Python scripting GDB now has support for scripting using Python. Whether this is available is determined at configure time. New GDB commands can now be written in Python. * Ada tasking support Ada tasks can now be inspected in GDB. The following commands have been introduced: info tasks Print the list of Ada tasks. info task N Print detailed information about task number N. task Print the task number of the current task. task N Switch the context of debugging to task number N. * Support for user-defined prefixed commands. The "define" command can add new commands to existing prefixes, e.g. "target". * Multi-inferior, multi-process debugging. GDB now has generalized support for multi-inferior debugging. See "Debugging Multiple Inferiors" in the manual for more information. Although availability still depends on target support, the command set is more uniform now. The GNU/Linux specific multi-forks support has been migrated to this new framework. This implied some user visible changes; see "New commands" and also "Removed commands" below. * Target descriptions can now describe the target OS ABI. See the "Target Description Format" section in the user manual for more information. * Target descriptions can now describe "compatible" architectures to indicate that the target can execute applications for a different architecture in addition to those for the main target architecture. See the "Target Description Format" section in the user manual for more information. * Multi-architecture debugging. GDB now includes general supports for debugging applications on hybrid systems that use more than one single processor architecture at the same time. Each such hybrid architecture still requires specific support to be added. The only hybrid architecture supported in this version of GDB is the Cell Broadband Engine. * GDB now supports integrated debugging of Cell/B.E. applications that use both the PPU and SPU architectures. To enable support for hybrid Cell/B.E. debugging, you need to configure GDB to support both the powerpc-linux or powerpc64-linux and the spu-elf targets, using the --enable-targets configure option. * Non-stop mode debugging. For some targets, GDB now supports an optional mode of operation in which you can examine stopped threads while other threads continue to execute freely. This is referred to as non-stop mode, with the old mode referred to as all-stop mode. See the "Non-Stop Mode" section in the user manual for more information. To be able to support remote non-stop debugging, a remote stub needs to implement the non-stop mode remote protocol extensions, as described in the "Remote Non-Stop" section of the user manual. The GDB remote stub, gdbserver, has been adjusted to support these extensions on linux targets. * New commands (for set/show, see "New options" below) catch syscall [NAME(S) | NUMBER(S)] Catch system calls. Arguments, which should be names of system calls or their numbers, mean catch only those syscalls. Without arguments, every syscall will be caught. When the inferior issues any of the specified syscalls, GDB will stop and announce the system call, both when it is called and when its call returns. This feature is currently available with a native GDB running on the Linux Kernel, under the following architectures: x86, x86_64, PowerPC and PowerPC64. find [/size-char] [/max-count] start-address, end-address|+search-space-size, val1 [, val2, ...] Search memory for a sequence of bytes. maint set python print-stack maint show python print-stack Show a stack trace when an error is encountered in a Python script. python [CODE] Invoke CODE by passing it to the Python interpreter. macro define macro list macro undef These allow macros to be defined, undefined, and listed interactively. info os processes Show operating system information about processes. info inferiors List the inferiors currently under GDB's control. inferior NUM Switch focus to inferior number NUM. detach inferior NUM Detach from inferior number NUM. kill inferior NUM Kill inferior number NUM. * New options set spu stop-on-load show spu stop-on-load Control whether to stop for new SPE threads during Cell/B.E. debugging. set spu auto-flush-cache show spu auto-flush-cache Control whether to automatically flush the software-managed cache during Cell/B.E. debugging. set sh calling-convention show sh calling-convention Control the calling convention used when calling SH target functions. set debug timestamp show debug timestamp Control display of timestamps with GDB debugging output. set disassemble-next-line show disassemble-next-line Control display of disassembled source lines or instructions when the debuggee stops. set remote noack-packet show remote noack-packet Set/show the use of remote protocol QStartNoAckMode packet. See above under "New remote packets." set remote query-attached-packet show remote query-attached-packet Control use of remote protocol `qAttached' (query-attached) packet. set remote read-siginfo-object show remote read-siginfo-object Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object) packet. set remote write-siginfo-object show remote write-siginfo-object Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object) packet. set remote reverse-continue show remote reverse-continue Control use of remote protocol 'bc' (reverse-continue) packet. set remote reverse-step show remote reverse-step Control use of remote protocol 'bs' (reverse-step) packet. set displaced-stepping show displaced-stepping Control displaced stepping mode. Displaced stepping is a way to single-step over breakpoints without removing them from the debuggee. Also known as "out-of-line single-stepping". set debug displaced show debug displaced Control display of debugging info for displaced stepping. maint set internal-error maint show internal-error Control what GDB does when an internal error is detected. maint set internal-warning maint show internal-warning Control what GDB does when an internal warning is detected. set exec-wrapper show exec-wrapper unset exec-wrapper Use a wrapper program to launch programs for debugging. set multiple-symbols (all|ask|cancel) show multiple-symbols The value of this variable can be changed to adjust the debugger behavior when an expression or a breakpoint location contains an ambiguous symbol name (an overloaded function name, for instance). set breakpoint always-inserted show breakpoint always-inserted Keep breakpoints always inserted in the target, as opposed to inserting them when resuming the target, and removing them when the target stops. This option can improve debugger performance on slow remote targets. set arm fallback-mode (arm|thumb|auto) show arm fallback-mode set arm force-mode (arm|thumb|auto) show arm force-mode These commands control how ARM GDB determines whether instructions are ARM or Thumb. The default for both settings is auto, which uses the current CPSR value for instructions without symbols; previous versions of GDB behaved as if "set arm fallback-mode arm". set disable-randomization show disable-randomization Standalone programs run with the virtual address space randomization enabled by default on some platforms. This option keeps the addresses stable across multiple debugging sessions. set non-stop show non-stop Control whether other threads are stopped or not when some thread hits a breakpoint. set target-async show target-async Requests that asynchronous execution is enabled in the target, if available. In this case, it's possible to resume target in the background, and interact with GDB while the target is running. "show target-async" displays the current state of asynchronous execution of the target. set target-wide-charset show target-wide-charset The target-wide-charset is the name of the character set that GDB uses when printing characters whose type is wchar_t. set tcp auto-retry (on|off) show tcp auto-retry set tcp connect-timeout show tcp connect-timeout These commands allow GDB to retry failed TCP connections to a remote stub with a specified timeout period; this is useful if the stub is launched in parallel with GDB but may not be ready to accept connections immediately. set libthread-db-search-path show libthread-db-search-path Control list of directories which GDB will search for appropriate libthread_db. set schedule-multiple (on|off) show schedule-multiple Allow GDB to resume all threads of all processes or only threads of the current process. set stack-cache show stack-cache Use more aggressive caching for accesses to the stack. This improves performance of remote debugging (particularly backtraces) without affecting correctness. set interactive-mode (on|off|auto) show interactive-mode Control whether GDB runs in interactive mode (on) or not (off). When in interactive mode, GDB waits for the user to answer all queries. Otherwise, GDB does not wait and assumes the default answer. When set to auto (the default), GDB determines which mode to use based on the stdin settings. * Removed commands info forks For program forks, this is replaced by the new more generic `info inferiors' command. To list checkpoints, you can still use the `info checkpoints' command, which was an alias for the `info forks' command. fork NUM Replaced by the new `inferior' command. To switch between checkpoints, you can still use the `restart' command, which was an alias for the `fork' command. process PID This is removed, since some targets don't have a notion of processes. To switch between processes, you can still use the `inferior' command using GDB's own inferior number. delete fork NUM For program forks, this is replaced by the new more generic `kill inferior' command. To delete a checkpoint, you can still use the `delete checkpoint' command, which was an alias for the `delete fork' command. detach fork NUM For program forks, this is replaced by the new more generic `detach inferior' command. To detach a checkpoint, you can still use the `detach checkpoint' command, which was an alias for the `detach fork' command. * New native configurations x86/x86_64 Darwin i[34567]86-*-darwin* x86_64 MinGW x86_64-*-mingw* * New targets Lattice Mico32 lm32-* x86 DICOS i[34567]86-*-dicos* x86_64 DICOS x86_64-*-dicos* S+core 3 score-*-* * The GDB remote stub, gdbserver, now supports x86 Windows CE (mingw32ce) debugging. * Removed commands catch load catch unload These commands were actually not implemented on any target. *** Changes in GDB 6.8 * New native configurations NetBSD/hppa hppa*-*netbsd* Xtensa GNU/Linux xtensa*-*-linux* * New targets NetBSD/hppa hppa*-*-netbsd* Xtensa GNU/Lunux xtensa*-*-linux* * Change in command line behavior -- corefiles vs. process ids. When the '-p NUMBER' or '--pid NUMBER' options are used, and attaching to process NUMBER fails, GDB no longer attempts to open a core file named NUMBER. Attaching to a program using the -c option is no longer supported. Instead, use the '-p' or '--pid' options. * GDB can now be built as a native debugger for debugging Windows x86 (mingw32) Portable Executable (PE) programs. * Pending breakpoints no longer change their number when their address is resolved. * GDB now supports breakpoints with multiple locations, including breakpoints on C++ constructors, inside C++ templates, and in inlined functions. * GDB's ability to debug optimized code has been improved. GDB more accurately identifies function bodies and lexical blocks that occupy more than one contiguous range of addresses. * Target descriptions can now describe registers for PowerPC. * The GDB remote stub, gdbserver, now supports the AltiVec and SPE registers on PowerPC targets. * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux targets even when the libthread_db library is not available. * The GDB remote stub, gdbserver, now supports the new file transfer commands (remote put, remote get, and remote delete). * The GDB remote stub, gdbserver, now supports run and attach in extended-remote mode. * hppa*64*-*-hpux11* target broken The debugger is unable to start a program and fails with the following error: "Error trying to get information about dynamic linker". The gdb-6.7 release is also affected. * GDB now supports the --enable-targets= configure option to allow building a single GDB executable that supports multiple remote target architectures. * GDB now supports debugging C and C++ programs which use the Decimal Floating Point extension. In addition, the PowerPC target now has a set of pseudo-registers to inspect decimal float values stored in two consecutive float registers. * The -break-insert MI command can optionally create pending breakpoints now. * Improved support for debugging Ada Many improvements to the Ada language support have been made. These include: - Better support for Ada2005 interface types - Improved handling of arrays and slices in general - Better support for Taft-amendment types - The '{type} ADDRESS' expression is now allowed on the left hand-side of an assignment - Improved command completion in Ada - Several bug fixes * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new process. * New commands set print frame-arguments (all|scalars|none) show print frame-arguments The value of this variable can be changed to control which argument values should be printed by the debugger when displaying a frame. remote put remote get remote delete Transfer files to and from a remote target, and delete remote files. * New MI commands -target-file-put -target-file-get -target-file-delete Transfer files to and from a remote target, and delete remote files. * New remote packets vFile:open: vFile:close: vFile:pread: vFile:pwrite: vFile:unlink: Open, close, read, write, and delete files on the remote system. vAttach Attach to an existing process on the remote system, in extended-remote mode. vRun Run a new process on the remote system, in extended-remote mode. *** Changes in GDB 6.7 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb, bfd, libiberty and opcodes, as revealed by static analysis donated by Coverity, Inc. (http://scan.coverity.com). * When looking up multiply-defined global symbols, GDB will now prefer the symbol definition in the current shared library if it was built using the -Bsymbolic linker option. * When the Text User Interface (TUI) is not configured, GDB will now recognize the -tui command-line option and print a message that the TUI is not supported. * The GDB remote stub, gdbserver, now has lower overhead for high frequency signals (e.g. SIGALRM) via the QPassSignals packet. * GDB for MIPS targets now autodetects whether a remote target provides 32-bit or 64-bit register values. * Support for C++ member pointers has been improved. * GDB now understands XML target descriptions, which specify the target's overall architecture. GDB can read a description from a local file or over the remote serial protocol. * Vectors of single-byte data use a new integer type which is not automatically displayed as character or string data. * The /s format now works with the print command. It displays arrays of single-byte integers and pointers to single-byte integers as strings. * Target descriptions can now describe target-specific registers, for architectures which have implemented the support (currently only ARM, M68K, and MIPS). * GDB and the GDB remote stub, gdbserver, now support the XScale iWMMXt coprocessor. * The GDB remote stub, gdbserver, has been updated to support ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support has been rewritten to use the standard GDB remote protocol. * GDB can now step into C++ functions which are called through thunks. * GDB for the Cell/B.E. SPU now supports overlay debugging. * The GDB remote protocol "qOffsets" packet can now honor ELF segment layout. It also supports a TextSeg= and DataSeg= response when only segment base addresses (rather than offsets) are available. * The /i format now outputs any trailing branch delay slot instructions immediately following the last instruction within the count specified. * The GDB remote protocol "T" stop reply packet now supports a "library" response. Combined with the new "qXfer:libraries:read" packet, this response allows GDB to debug shared libraries on targets where the operating system manages the list of loaded libraries (e.g. Windows and SymbianOS). * The GDB remote stub, gdbserver, now supports dynamic link libraries (DLLs) on Windows and Windows CE targets. * GDB now supports a faster verification that a .debug file matches its binary according to its build-id signature, if the signature is present. * New commands set remoteflow show remoteflow Enable or disable hardware flow control (RTS/CTS) on the serial port when debugging using remote targets. set mem inaccessible-by-default show mem inaccessible-by-default If the target supplies a memory map, for instance via the remote protocol's "qXfer:memory-map:read" packet, setting this variable prevents GDB from accessing memory outside the memory map. This is useful for targets with memory mapped registers or which react badly to accesses of unmapped address space. set breakpoint auto-hw show breakpoint auto-hw If the target supplies a memory map, for instance via the remote protocol's "qXfer:memory-map:read" packet, setting this variable lets GDB use hardware breakpoints automatically for memory regions where it can not use software breakpoints. This covers both the "break" command and internal breakpoints used for other commands including "next" and "finish". catch exception catch exception unhandled Stop the program execution when Ada exceptions are raised. catch assert Stop the program execution when an Ada assertion failed. set sysroot show sysroot Set an alternate system root for target files. This is a more general version of "set solib-absolute-prefix", which is now an alias to "set sysroot". info spu Provide extended SPU facility status information. This set of commands is available only when debugging the Cell/B.E. SPU architecture. * New native configurations OpenBSD/sh sh*-*openbsd* set tdesc filename unset tdesc filename show tdesc filename Use the specified local file as an XML target description, and do not query the target for its built-in description. * New targets OpenBSD/sh sh*-*-openbsd* MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu Toshiba Media Processor mep-elf * New remote packets QPassSignals: Ignore the specified signals; pass them directly to the debugged program without stopping other threads or reporting them to GDB. qXfer:features:read: Read an XML target description from the target, which describes its features. qXfer:spu:read: qXfer:spu:write: Read or write contents of an spufs file on the target system. These packets are available only on the Cell/B.E. SPU architecture. qXfer:libraries:read: Report the loaded shared libraries. Combined with new "T" packet response, this packet allows GDB to debug shared libraries on targets where the operating system manages the list of loaded libraries (e.g. Windows and SymbianOS). * Removed targets Support for these obsolete configurations has been removed. alpha*-*-osf1* alpha*-*-osf2* d10v-*-* hppa*-*-hiux* i[34567]86-ncr-* i[34567]86-*-dgux* i[34567]86-*-lynxos* i[34567]86-*-netware* i[34567]86-*-sco3.2v5* i[34567]86-*-sco3.2v4* i[34567]86-*-sco* i[34567]86-*-sysv4.2* i[34567]86-*-sysv4* i[34567]86-*-sysv5* i[34567]86-*-unixware2* i[34567]86-*-unixware* i[34567]86-*-sysv* i[34567]86-*-isc* m68*-cisco*-* m68*-tandem-* mips*-*-pe rs6000-*-lynxos* sh*-*-pe * Other removed features target abug target cpu32bug target est target rom68k Various m68k-only ROM monitors. target hms target e7000 target sh3 target sh3e Various Renesas ROM monitors and debugging interfaces for SH and H8/300. target ocd Support for a Macraigor serial interface to on-chip debugging. GDB does not directly support the newer parallel or USB interfaces. DWARF 1 support A debug information format. The predecessor to DWARF 2 and DWARF 3, which are still supported. Support for the HP aCC compiler on HP-UX/PA-RISC SOM-encapsulated symbolic debugging information, automatic invocation of pxdb, and the aCC custom C++ ABI. This does not affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled with aCC can still be debugged on an assembly level. MIPS ".pdr" sections A MIPS-specific format used to describe stack frame layout in debugging information. Scheme support GDB could work with an older version of Guile to debug the interpreter and Scheme programs running in it. set mips stack-arg-size set mips saved-gpreg-size Use "set mips abi" to control parameter passing for MIPS. *** Changes in GDB 6.6 * New targets Xtensa xtensa-elf Cell Broadband Engine SPU spu-elf * GDB can now be configured as a cross-debugger targeting native Windows (mingw32) or Cygwin. It can communicate with a remote debugging stub running on a Windows system over TCP/IP to debug Windows programs. * The GDB remote stub, gdbserver, has been updated to support Windows and Cygwin debugging. Both single-threaded and multi-threaded programs are supported. * The "set trust-readonly-sections" command works again. This command was broken in GDB 6.3, 6.4, and 6.5. * The "load" command now supports writing to flash memory, if the remote stub provides the required support. * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no longer requires symbolic debug information (e.g. DWARF-2). * New commands set substitute-path unset substitute-path show substitute-path Manage a list of substitution rules that GDB uses to rewrite the name of the directories where the sources are located. This can be useful for instance when the sources were moved to a different location between compilation and debugging. set trace-commands show trace-commands Print each CLI command as it is executed. Each command is prefixed with a number of `+' symbols representing the nesting depth. The source command now has a `-v' option to enable the same feature. * REMOVED features The ARM Demon monitor support (RDP protocol, "target rdp"). Kernel Object Display, an embedded debugging feature which only worked with an obsolete version of Cisco IOS. The 'set download-write-size' and 'show download-write-size' commands. * New remote packets qSupported: Tell a stub about GDB client features, and request remote target features. The first feature implemented is PacketSize, which allows the target to specify the size of packets it can handle - to minimize the number of packets required and improve performance when connected to a remote target. qXfer:auxv:read: Fetch an OS auxilliary vector from the remote stub. This packet is a more efficient replacement for qPart:auxv:read. qXfer:memory-map:read: Fetch a memory map from the remote stub, including information about RAM, ROM, and flash memory devices. vFlashErase: vFlashWrite: vFlashDone: Erase and program a flash memory device. * Removed remote packets qPart:auxv:read: This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5 used it, and only gdbserver implemented it. *** Changes in GDB 6.5 * New targets Renesas M32C/M16C m32c-elf Morpho Technologies ms1 ms1-elf * New commands init-if-undefined Initialize a convenience variable, but only if it doesn't already have a value. The following commands are presently only implemented for native GNU/Linux: checkpoint Save a snapshot of the program state. restart Return the program state to a previously saved state. info checkpoints List currently saved checkpoints. delete-checkpoint Delete a previously saved checkpoint. set|show detach-on-fork Tell gdb whether to detach from a newly forked process, or to keep debugging it. info forks List forks of the user program that are available to be debugged. fork Switch to debugging one of several forks of the user program that are available to be debugged. delete-fork Delete a fork from the list of forks that are available to be debugged (and kill the forked process). detach-fork Delete a fork from the list of forks that are available to be debugged (and allow the process to continue). * New architecture Morpho Technologies ms2 ms1-elf * Improved Windows host support GDB now builds as a cross debugger hosted on i686-mingw32, including native console support, and remote communications using either network sockets or serial ports. * Improved Modula-2 language support GDB can now print most types in the Modula-2 syntax. This includes: basic types, set types, record types, enumerated types, range types, pointer types and ARRAY types. Procedure var parameters are correctly printed and hexadecimal addresses and character constants are also written in the Modula-2 syntax. Best results can be obtained by using GNU Modula-2 together with the -gdwarf-2 command line option. * REMOVED features The ARM rdi-share module. The Netware NLM debug server. *** Changes in GDB 6.4 * New native configurations OpenBSD/arm arm*-*-openbsd* OpenBSD/mips64 mips64-*-openbsd* * New targets Morpho Technologies ms1 ms1-elf * New command line options --batch-silent As for --batch, but totally silent. --return-child-result The debugger will exist with the same value the child (debugged) program exited with. --eval-command COMMAND, -ex COMMAND Execute a single GDB CLI command. This may be specified multiple times and in conjunction with the --command (-x) option. * Deprecated commands removed The following commands, that were deprecated in 2000, have been removed: Command Replacement set|show arm disassembly-flavor set|show arm disassembler othernames set arm disassembler set|show remotedebug set|show debug remote set|show archdebug set|show debug arch set|show eventdebug set|show debug event regs info registers * New BSD user-level threads support It is now possible to debug programs using the user-level threads library on OpenBSD and FreeBSD. Currently supported (target) configurations are: FreeBSD/amd64 x86_64-*-freebsd* FreeBSD/i386 i386-*-freebsd* OpenBSD/i386 i386-*-openbsd* Note that the new kernel threads libraries introduced in FreeBSD 5.x are not yet supported. * New support for Matsushita MN10300 w/sim added (Work in progress). mn10300-elf. * REMOVED configurations and files VxWorks and the XDR protocol *-*-vxworks Motorola MCORE mcore-*-* National Semiconductor NS32000 ns32k-*-* * New "set print array-indexes" command After turning this setting "on", GDB prints the index of each element when displaying arrays. The default is "off" to preserve the previous behavior. * VAX floating point support GDB now supports the not-quite-ieee VAX F and D floating point formats. * User-defined command support In addition to using $arg0..$arg9 for argument passing, it is now possible to use $argc to determine now many arguments have been passed. See the section on user-defined commands in the user manual for more information. *** Changes in GDB 6.3: * New command line option GDB now accepts -l followed by a number to set the timeout for remote debugging. * GDB works with GCC -feliminate-dwarf2-dups GDB now supports a more compact representation of DWARF-2 debug information using DW_FORM_ref_addr references. These are produced by GCC with the option -feliminate-dwarf2-dups and also by some proprietary compilers. With GCC, you must use GCC 3.3.4 or later to use -feliminate-dwarf2-dups. * Internationalization When supported by the host system, GDB will be built with internationalization (libintl). The task of marking up the sources is continued, we're looking forward to our first translation. * Ada Initial support for debugging programs compiled with the GNAT implementation of the Ada programming language has been integrated into GDB. In this release, support is limited to expression evaluation. * New native configurations GNU/Linux/m32r m32r-*-linux-gnu * Remote 'p' packet GDB's remote protocol now includes support for the 'p' packet. This packet is used to fetch individual registers from a remote inferior. * END-OF-LIFE registers[] compatibility module GDB's internal register infrastructure has been completely rewritten. The new infrastructure making possible the implementation of key new features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit i386 application). GDB 6.3 will be the last release to include the the registers[] compatibility module that allowed out-of-date configurations to continue to work. This change directly impacts the following configurations: hppa-*-hpux ia64-*-aix mips-*-irix* *-*-lynx mips-*-linux-gnu sds protocol xdr protocol powerpc bdm protocol Unless there is activity to revive these configurations, they will be made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5. * 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. h8300-*-* mcore-*-* mn10300-*-* ns32k-*-* sh64-*-* v850-*-* *** Changes in GDB 6.2.1: * MIPS `break main; run' gave an heuristic-fence-post warning When attempting to run even a simple program, a warning about heuristic-fence-post being hit would be reported. This problem has been fixed. * MIPS IRIX 'long double' crashed GDB When examining a long double variable, GDB would get a segmentation fault. The crash has been fixed (but GDB 6.2 cannot correctly examine IRIX long double values). * VAX and "next" A bug in the VAX stack code was causing problems with the "next" command. This problem has been fixed. *** Changes in GDB 6.2: * Fix for ``many threads'' On GNU/Linux systems that use the NPTL threads library, a program rapidly creating and deleting threads would confuse GDB leading to the error message: ptrace: No such process. thread_db_get_info: cannot get thread info: generic error This problem has been fixed. * "-async" and "-noasync" options removed. Support for the broken "-noasync" option has been removed (it caused GDB to dump core). * New ``start'' command. This command runs the program until the begining of the main procedure. * New BSD Kernel Data Access Library (libkvm) interface Using ``target kvm'' it is now possible to debug kernel core dumps and live kernel memory images on various FreeBSD, NetBSD and OpenBSD platforms. Currently supported (native-only) configurations are: FreeBSD/amd64 x86_64-*-freebsd* FreeBSD/i386 i?86-*-freebsd* NetBSD/i386 i?86-*-netbsd* NetBSD/m68k m68*-*-netbsd* NetBSD/sparc sparc-*-netbsd* OpenBSD/amd64 x86_64-*-openbsd* OpenBSD/i386 i?86-*-openbsd* OpenBSD/m68k m68*-openbsd* OpenBSD/sparc sparc-*-openbsd* * Signal trampoline code overhauled Many generic problems with GDB's signal handling code have been fixed. These include: backtraces through non-contiguous stacks; recognition of sa_sigaction signal trampolines; backtrace from a NULL pointer call; backtrace through a signal trampoline; step into and out of signal handlers; and single-stepping in the signal trampoline. Please note that kernel bugs are a limiting factor here. These features have been shown to work on an s390 GNU/Linux system that include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702. * Cygwin support for DWARF 2 added. * New native configurations GNU/Linux/hppa hppa*-*-linux* OpenBSD/hppa hppa*-*-openbsd* OpenBSD/m68k m68*-*-openbsd* OpenBSD/m88k m88*-*-openbsd* OpenBSD/powerpc powerpc-*-openbsd* NetBSD/vax vax-*-netbsd* OpenBSD/vax vax-*-openbsd* * END-OF-LIFE frame compatibility module GDB's internal frame infrastructure has been completely rewritten. The new infrastructure making it possible to support key new features including DWARF 2 Call Frame Information. To aid in the task of migrating old configurations to this new infrastructure, a compatibility module, that allowed old configurations to continue to work, was also included. GDB 6.2 will be the last release to include this frame compatibility module. This change directly impacts the following configurations: h8300-*-* mcore-*-* mn10300-*-* ns32k-*-* sh64-*-* v850-*-* xstormy16-*-* Unless there is activity to revive these configurations, they will be made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4. * REMOVED configurations and files Sun 3, running SunOS 3 m68*-*-sunos3* Sun 3, running SunOS 4 m68*-*-sunos4* Sun 2, running SunOS 3 m68000-*-sunos3* Sun 2, running SunOS 4 m68000-*-sunos4* Motorola 680x0 running LynxOS m68*-*-lynxos* AT&T 3b1/Unix pc m68*-att-* Bull DPX2 (68k, System V release 3) m68*-bull-sysv* decstation mips-dec-* mips-little-* riscos mips-*-riscos* mips-*-sysv* sonymips mips-sony-* sysv mips*-*-sysv4* (IRIX 5/6 not included) *** Changes in GDB 6.1.1: * TUI (Text-mode User Interface) built-in (also included in GDB 6.1) The TUI (Text-mode User Interface) is now built as part of a default GDB configuration. It is enabled by either selecting the TUI with the command line option "-i=tui" or by running the separate "gdbtui" program. For more information on the TUI, see the manual "Debugging with GDB". * Pending breakpoint support (also included in GDB 6.1) Support has been added to allow you to specify breakpoints in shared libraries that have not yet been loaded. If a breakpoint location cannot be found, and the "breakpoint pending" option is set to auto, GDB queries you if you wish to make the breakpoint pending on a future shared-library load. If and when GDB resolves the breakpoint symbol, the pending breakpoint is removed as one or more regular breakpoints are created. Pending breakpoints are very useful for GCJ Java debugging. * Fixed ISO-C build problems The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained non ISO-C code that stopped them being built using a more strict ISO-C compiler (e.g., IBM's C compiler). * Fixed build problem on IRIX 5 Due to header problems with , the file gdb/proc-api.c wasn't able to compile compile on an IRIX 5 system. * Added execute permission to gdb/gdbserver/configure The shell script gdb/testsuite/gdb.stabs/configure lacked execute permission. This bug would cause configure to fail on a number of systems (Solaris, IRIX). Ref: server/519. * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c has been updated to use constant array sizes. * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in its generated DWARF Call Frame Info. This encoding was causing GDB to panic, that panic has been fixed. Ref: gdb/1628. * Fixed a problem when examining parameters in shared library code. When examining parameters in optimized shared library code generated by a mainline GCC, GDB would incorrectly report ``Variable "..." is not available''. GDB now correctly displays the variable's value. *** Changes in GDB 6.1: * Removed --with-mmalloc Support for the mmalloc memory manager has been removed, as it conflicted with the internal gdb byte cache. * Changes in AMD64 configurations The AMD64 target now includes the %cs and %ss registers. As a result the AMD64 remote protocol has changed; this affects the floating-point and SSE registers. If you rely on those registers for your debugging, you should upgrade gdbserver on the remote side. * Revised SPARC target The SPARC target has been completely revised, incorporating the FreeBSD/sparc64 support that was added for GDB 6.0. As a result support for LynxOS and SunOS 4 has been dropped. Calling functions from within GDB on operating systems with a non-executable stack (Solaris, OpenBSD) now works. * New C++ demangler GDB has a new C++ demangler which does a better job on the mangled names generated by current versions of g++. It also runs faster, so with this and other changes gdb should now start faster on large C++ programs. * DWARF 2 Location Expressions GDB support for location expressions has been extended to support function arguments and frame bases. Older versions of GDB could crash when they encountered these. * C++ nested types and namespaces GDB's support for nested types and namespaces in C++ has been improved, especially if you use the DWARF 2 debugging format. (This is the default for recent versions of GCC on most platforms.) Specifically, if you have a class "Inner" defined within a class or namespace "Outer", then GDB realizes that the class's name is "Outer::Inner", not simply "Inner". This should greatly reduce the frequency of complaints about not finding RTTI symbols. In addition, if you are stopped at inside of a function defined within a namespace, GDB modifies its name lookup accordingly. * New native configurations NetBSD/amd64 x86_64-*-netbsd* OpenBSD/amd64 x86_64-*-openbsd* OpenBSD/alpha alpha*-*-openbsd* OpenBSD/sparc sparc-*-openbsd* OpenBSD/sparc64 sparc64-*-openbsd* * New debugging protocols M32R with SDI protocol m32r-*-elf* * "set prompt-escape-char" command deleted. The command "set prompt-escape-char" has been deleted. This command, and its very obscure effet on GDB's prompt, was never documented, tested, nor mentioned in the NEWS file. * 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. Sun 3, running SunOS 3 m68*-*-sunos3* Sun 3, running SunOS 4 m68*-*-sunos4* Sun 2, running SunOS 3 m68000-*-sunos3* Sun 2, running SunOS 4 m68000-*-sunos4* Motorola 680x0 running LynxOS m68*-*-lynxos* AT&T 3b1/Unix pc m68*-att-* Bull DPX2 (68k, System V release 3) m68*-bull-sysv* decstation mips-dec-* mips-little-* riscos mips-*-riscos* mips-*-sysv* sonymips mips-sony-* sysv mips*-*-sysv4* (IRIX 5/6 not included) * REMOVED configurations and files SGI Irix-4.x mips-sgi-irix4 or iris4 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris Z8000 simulator z8k-zilog-none or z8ksim Matsushita MN10200 w/simulator mn10200-*-* H8/500 simulator h8500-hitachi-hms or h8500hms HP/PA running BSD hppa*-*-bsd* HP/PA running OSF/1 hppa*-*-osf* HP/PA Pro target hppa*-*-pro* PMAX (MIPS) running Mach 3.0 mips*-*-mach3* 386BSD i[3456]86-*-bsd* Sequent family i[3456]86-sequent-sysv4* i[3456]86-sequent-sysv* i[3456]86-sequent-bsd* SPARC running LynxOS sparc-*-lynxos* SPARC running SunOS 4 sparc-*-sunos4* Tsqware Sparclet sparclet-*-* Fujitsu SPARClite sparclite-fujitsu-none or sparclite *** Changes in GDB 6.0: * Objective-C Support for debugging the Objective-C programming language has been integrated into GDB. * New backtrace mechanism (includes DWARF 2 Call Frame Information). DWARF 2's Call Frame Information makes available compiler generated information that more exactly describes the program's run-time stack. By using this information, GDB is able to provide more robust stack backtraces. The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets have been updated to use a new backtrace mechanism which includes DWARF 2 CFI support. * Hosted file I/O. GDB's remote protocol has been extended to include support for hosted file I/O (where the remote target uses GDB's file system). See GDB's remote protocol documentation for details. * All targets using the new architecture framework. All of GDB's targets have been updated to use the new internal architecture framework. The way is now open for future GDB releases to include cross-architecture native debugging support (i386 on amd64, ppc32 on ppc64). * GNU/Linux's Thread Local Storage (TLS) GDB now includes support for for the GNU/Linux implementation of per-thread variables. * GNU/Linux's Native POSIX Thread Library (NPTL) GDB's thread code has been updated to work with either the new GNU/Linux NPTL thread library or the older "LinuxThreads" library. * Separate debug info. GDB, in conjunction with BINUTILS, now supports a mechanism for automatically loading debug information from a separate file. Instead of shipping full debug and non-debug versions of system libraries, system integrators can now instead ship just the stripped libraries and optional debug files. * DWARF 2 Location Expressions DWARF 2 Location Expressions allow the compiler to more completely describe the location of variables (even in optimized code) to the debugger. GDB now includes preliminary support for location expressions (support for DW_OP_piece is still missing). * Java A number of long standing bugs that caused GDB to die while starting a Java application have been fixed. GDB's Java support is now considered "useable". * GNU/Linux support for fork, vfork, and exec. The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode" commands are now implemented for GNU/Linux. They require a 2.5.x or later kernel. * GDB supports logging output to a file There are two new commands, "set logging" and "show logging", which can be used to capture GDB's output to a file. * The meaning of "detach" has changed for gdbserver The "detach" command will now resume the application, as documented. To disconnect from gdbserver and leave it stopped, use the new "disconnect" command. * d10v, m68hc11 `regs' command deprecated The `info registers' command has been updated so that it displays the registers using a format identical to the old `regs' command. * Profiling support A new command, "maint set profile on/off", has been added. This command can be used to enable or disable profiling while running GDB, to profile a session or a set of commands. In addition there is a new configure switch, "--enable-profiling", which will cause GDB to be compiled with profiling data, for more informative profiling results. * Default MI syntax changed to "mi2". The default MI (machine interface) syntax, enabled by the command line option "-i=mi", has been changed to "mi2". The previous MI syntax, "mi1", can be enabled by specifying the option "-i=mi1". Support for the original "mi0" syntax (included in GDB 5.0) has been removed. Fix for gdb/192: removed extraneous space when displaying frame level. Fix for gdb/672: update changelist is now output in mi list format. Fix for gdb/702: a -var-assign that updates the value now shows up in a subsequent -var-update. * New native configurations. FreeBSD/amd64 x86_64-*-freebsd* * Multi-arched targets. HP/PA HPUX11 hppa*-*-hpux* Renesas M32R/D w/simulator m32r-*-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. Z8000 simulator z8k-zilog-none or z8ksim Matsushita MN10200 w/simulator mn10200-*-* H8/500 simulator h8500-hitachi-hms or h8500hms HP/PA running BSD hppa*-*-bsd* HP/PA running OSF/1 hppa*-*-osf* HP/PA Pro target hppa*-*-pro* PMAX (MIPS) running Mach 3.0 mips*-*-mach3* Sequent family i[3456]86-sequent-sysv4* i[3456]86-sequent-sysv* i[3456]86-sequent-bsd* Tsqware Sparclet sparclet-*-* Fujitsu SPARClite sparclite-fujitsu-none or sparclite * REMOVED configurations and files V850EA ISA Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88 IBM AIX PS/2 i[3456]86-*-aix i386 running Mach 3.0 i[3456]86-*-mach3* i386 running Mach i[3456]86-*-mach* i386 running OSF/1 i[3456]86-*osf1mk* HP/Apollo 68k Family m68*-apollo*-sysv*, m68*-apollo*-bsd*, m68*-hp-bsd*, m68*-hp-hpux* Argonaut Risc Chip (ARC) arc-*-* Mitsubishi D30V d30v-*-* Fujitsu FR30 fr30-*-elf* OS/9000 i[34]86-*-os9k I960 with MON960 i960-*-coff * MIPS $fp behavior changed The convenience variable $fp, for the MIPS, now consistently returns the address of the current frame's base. Previously, depending on the context, $fp could refer to either $sp or the current frame's base address. See ``8.10 Registers'' in the manual ``Debugging with GDB: The GNU Source-Level Debugger''. *** Changes in GDB 5.3: * GNU/Linux shared library multi-threaded performance improved. When debugging a multi-threaded application on GNU/Linux, GDB now uses `/proc', in preference to `ptrace' for memory reads. This may result in an improvement in the start-up time of multi-threaded, shared library applications when run under GDB. One GDB user writes: ``loads shared libs like mad''. * ``gdbserver'' now supports multi-threaded applications on some targets Support for debugging multi-threaded applications which use the GNU/Linux LinuxThreads package has been added for arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*, powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*. * 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. The new command `macro expand EXPRESSION' expands any macro invocations in expression, and shows the result. The new command `show macro MACRO-NAME' shows the definition of the macro named MACRO-NAME, and where it was defined. 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. * 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. 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-*-* OS/9000 i[34]86-*-os9k IBM AIX PS/2 i[3456]86-*-aix Fujitsu FR30 fr30-*-elf* Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88 Argonaut Risc Chip (ARC) arc-*-* i386 running Mach 3.0 i[3456]86-*-mach3* i386 running Mach i[3456]86-*-mach* i386 running OSF/1 i[3456]86-*osf1mk* HP/Apollo 68k Family m68*-apollo*-sysv*, m68*-apollo*-bsd*, m68*-hp-bsd*, m68*-hp-hpux* I960 with MON960 i960-*-coff * OBSOLETE languages CHILL, a Pascal like language used by telecommunications companies. * 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). * Improved "next/step" support on multi-processor Alpha Tru64. The previous single-step mechanism could cause unpredictable problems, including the random appearance of SIGSEGV or SIGTRAP signals. The use of a software single-step mechanism prevents this. *** Changes in GDB 5.2.1: * New targets. Atmel AVR avr*-*-* * Bug fixes gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting: mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized Fix, by Joel Brobecker imported from mainline. gdb/439: gdb/291: On some ELF object files, gdb was reporting: dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize Fix, by Fred Fish, imported from mainline. Dwarf2 .debug_frame & .eh_frame handler improved in many ways. Surprisingly enough, it works now. By Michal Ludvig, imported from mainline. i386 hardware watchpoint support: avoid misses on second run for some targets. By Pierre Muller, imported from mainline. *** 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.