source: trunk/src/gcc/include/ansidecl.h@ 1706

/* ANSI and traditional C compatability macros
   Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001
   Free Software Foundation, Inc.
   This file is part of the GNU C Library.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

/* ANSI and traditional C compatibility macros

   ANSI C is assumed if __STDC__ is #defined.

   Macro                ANSI C definition       Traditional C definition
   -----                ---- - ----------       ----------- - ----------
   ANSI_PROTOTYPES      1                       not defined
   PTR                  `void *'                `char *'
   PTRCONST             `void *const'           `char *'
   LONG_DOUBLE          `long double'           `double'
   const                not defined             `'
   volatile             not defined             `'
   signed               not defined             `'
   VA_START(ap, var)    va_start(ap, var)       va_start(ap)

   Note that it is safe to write "void foo();" indicating a function
   with no return value, in all K+R compilers we have been able to test.

   For declaring functions with prototypes, we also provide these:

   PARAMS ((prototype))
   -- for functions which take a fixed number of arguments.  Use this
   when declaring the function.  When defining the function, write a
   K+R style argument list.  For example:

        char *strcpy PARAMS ((char *dest, char *source));
        ...
        char *
        strcpy (dest, source)
             char *dest;
             char *source;
        { ... }


   VPARAMS ((prototype, ...))
   -- for functions which take a variable number of arguments.  Use
   PARAMS to declare the function, VPARAMS to define it.  For example:

        int printf PARAMS ((const char *format, ...));
        ...
        int
        printf VPARAMS ((const char *format, ...))
        {
           ...
        }

   For writing functions which take variable numbers of arguments, we
   also provide the VA_OPEN, VA_CLOSE, and VA_FIXEDARG macros.  These
   hide the differences between K+R <varargs.h> and C89 <stdarg.h> more
   thoroughly than the simple VA_START() macro mentioned above.

   VA_OPEN and VA_CLOSE are used *instead of* va_start and va_end.
   Immediately after VA_OPEN, put a sequence of VA_FIXEDARG calls
   corresponding to the list of fixed arguments.  Then use va_arg
   normally to get the variable arguments, or pass your va_list object
   around.  You do not declare the va_list yourself; VA_OPEN does it
   for you.

   Here is a complete example:

        int
        printf VPARAMS ((const char *format, ...))
        {
           int result;

           VA_OPEN (ap, format);
           VA_FIXEDARG (ap, const char *, format);

           result = vfprintf (stdout, format, ap);
           VA_CLOSE (ap);

           return result;
        }