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diff --git a/gdb/WHATS.NEW b/gdb/WHATS.NEW new file mode 100755 index 0000000..97b0415 --- /dev/null +++ b/gdb/WHATS.NEW @@ -0,0 +1,223 @@ + GDB 4.0 -- what has changed since 3.5? + + * New Facilities + +Gdb now paginates its output, with a ``more''-like interface. You can +set the screen width and screen height with new ``set'' commands; they +default to your terminal settings. Wide output is wrapped at good +places to make the output more readable. + +Gdb now reads its input via the ``readline'' interface. This provides +inline editing of commands, using familiar Emacs or VI commands (like +``tcsh'' or the korn shell); history substitutions a la the C shell; +and storage and recall of your command history across debugging +sessions. The default is Emacs mode; to switch temporarily to vi mode, +use control-meta-J or ESC control-j. You can switch permanently to vi +mode by putting the line ``set editing-mode vi'' in the file .inputrc +in your home directory. For full details, see the description in +readline/inc-readline.texinfo and readline/inc-history.texinfo. + +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. It 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 "gdbrc.tex". + + + * 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. + +caution 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 write 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. + +screen-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. + +screen-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 screen-height'' and +``set screen-width'' instead. + +addressprint 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. + +arrayprint on/off: Prettyprint arrays. New convenient format! Default + is OFF. + +demangle on/off: Print C++ symbols in "source" form if on, "raw" form if off. + +asm-demangle on/off: Same, for assembler level printouts like instructions. + +vtblprint 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; GCC includes this information. If GDB can't find +your source file in the current directory, type "dir .". + + * Features removed in this release + +``info types'' has been removed, since it printed builtin types in a +confusing fashion, and did not do useful things with typedefs. ``ptype'' +or ``whatis'' are more useful commands for dealing with types.. + + + * Configuring GDB for compilation + +For normal use, type ``config.gdb host''. Hosts now handled are: + +3b1 altos altosgas arm bigmips convex hp300bsd hp300hpux i386v i386v-g +i386v32 i386v32-g isi littlemips m88k merlin news news1000 none np1 pn +pyramid sun2os3 sun2os4 sun386 sun3os3 sun3os4 sun4os3 sun4os4 symmetry +umax vax + +Type config.gdb +host to get a full description of each host. + +You can now build gdb conveniently for several architectures from the +same sources. If config.gdb is run from a subdirectory, it configures +the Makefile to use source files from '..'. Each subdirectory can be +indpendently configured. An explicit source file directory can also +be specified with the +srcdir=xxx option. Due to obscure search rules +in the C preprocessor, if you have previously built gdb in the main +directory, run 'make cleanconfig' in the top level directory before +building it in a subdirectory. + +GDB now handles cross debugging. If you are remotely debugging between +two different machines, type ``config.gdb host target''. +Host is the machine where gdb will run; target is the machine +where the program that you are debugging will run. + +Type config.gdb +target to get a full description of each target. |