include/ansidecl.h

   1 /* ANSI and traditional C compatability macros
   2    Copyright 1991, 1992, 1996, 1999 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation; either version 2 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; if not, write to the Free Software
  17 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  18
  19 /* ANSI and traditional C compatibility macros
  20
  21    ANSI C is assumed if __STDC__ is #defined.
  22
  23    Macro        ANSI C definition       Traditional C definition
  24    -----        ---- - ----------       ----------- - ----------
  25    PTR          `void *'                `char *'
  26    LONG_DOUBLE  `long double'           `double'
  27    VOLATILE     `volatile'              `'
  28    SIGNED       `signed'                `'
  29    PTRCONST     `void *const'           `char *'
  30    ANSI_PROTOTYPES  1                   not defined
  31
  32    CONST is also defined, but is obsolete.  Just use const.
  33
  34    obsolete --     DEFUN (name, arglist, args)
  35
  36         Defines function NAME.
  37
  38         ARGLIST lists the arguments, separated by commas and enclosed in
  39         parentheses.  ARGLIST becomes the argument list in traditional C.
  40
  41         ARGS list the arguments with their types.  It becomes a prototype in
  42         ANSI C, and the type declarations in traditional C.  Arguments should
  43         be separated with `AND'.  For functions with a variable number of
  44         arguments, the last thing listed should be `DOTS'.
  45
  46    obsolete --     DEFUN_VOID (name)
  47
  48         Defines a function NAME, which takes no arguments.
  49
  50    obsolete --     EXFUN (name, (prototype))    -- obsolete.
  51
  52         Replaced by PARAMS.  Do not use; will disappear someday soon.
  53         Was used in external function declarations.
  54         In ANSI C it is `NAME PROTOTYPE' (so PROTOTYPE should be enclosed in
  55         parentheses).  In traditional C it is `NAME()'.
  56         For a function that takes no arguments, PROTOTYPE should be `(void)'.
  57
  58    obsolete --     PROTO (type, name, (prototype)    -- obsolete.
  59
  60         This one has also been replaced by PARAMS.  Do not use.
  61
  62    PARAMS ((args))
  63
  64         We could use the EXFUN macro to handle prototype declarations, but
  65         the name is misleading and the result is ugly.  So we just define a
  66         simple macro to handle the parameter lists, as in:
  67
  68               static int foo PARAMS ((int, char));
  69
  70         This produces:  `static int foo();' or `static int foo (int, char);'
  71
  72         EXFUN would have done it like this:
  73
  74               static int EXFUN (foo, (int, char));
  75
  76         but the function is not external...and it's hard to visually parse
  77         the function name out of the mess.   EXFUN should be considered
  78         obsolete; new code should be written to use PARAMS.
  79
  80    DOTS is also obsolete.
  81
  82    Examples:
  83
  84         extern int printf PARAMS ((const char *format, ...));
  85 */
  86
  87 #ifndef _ANSIDECL_H
  88
  89 #define _ANSIDECL_H     1
  90
  91
  92 /* Every source file includes this file,
  93    so they will all get the switch for lint.  */
  94 /* LINTLIBRARY */
  95
  96
  97 #if defined (__STDC__) || defined (_AIX) || (defined (__mips) && defined (_SYSTYPE_SVR4)) || defined(_WIN32)
  98 /* All known AIX compilers implement these things (but don't always
  99    define __STDC__).  The RISC/OS MIPS compiler defines these things
 100    in SVR4 mode, but does not define __STDC__.  */
 101
 102 #define PTR             void *
 103 #define PTRCONST        void *CONST
 104 #define LONG_DOUBLE     long double
 105
 106 #ifndef IN_GCC
 107 #define AND             ,
 108 #define NOARGS          void
 109 #define VOLATILE        volatile
 110 #define SIGNED          signed
 111 #endif /* ! IN_GCC */
 112
 113 #define PARAMS(paramlist)               paramlist
 114 #define ANSI_PROTOTYPES                 1
 115
 116 #define VPARAMS(ARGS)                   ARGS
 117 #define VA_START(va_list,var)           va_start(va_list,var)
 118
 119 /* These are obsolete.  Do not use.  */
 120 #ifndef IN_GCC
 121 #define CONST                           const
 122 #define DOTS                            , ...
 123 #define PROTO(type, name, arglist)      type name arglist
 124 #define EXFUN(name, proto)              name proto
 125 #define DEFUN(name, arglist, args)      name(args)
 126 #define DEFUN_VOID(name)                name(void)
 127 #endif /* ! IN_GCC */
 128
 129 #else   /* Not ANSI C.  */
 130
 131 #define PTR             char *
 132 #define PTRCONST        PTR
 133 #define LONG_DOUBLE     double
 134
 135 #ifndef IN_GCC
 136 #define AND             ;
 137 #define NOARGS
 138 #define VOLATILE
 139 #define SIGNED
 140 #endif /* !IN_GCC */
 141
 142 #ifndef const /* some systems define it in header files for non-ansi mode */
 143 #define const
 144 #endif
 145
 146 #define PARAMS(paramlist)               ()
 147
 148 #define VPARAMS(ARGS)                   (va_alist) va_dcl
 149 #define VA_START(va_list,var)           va_start(va_list)
 150
 151 /* These are obsolete.  Do not use.  */
 152 #ifndef IN_GCC
 153 #define CONST
 154 #define DOTS
 155 #define PROTO(type, name, arglist)      type name ()
 156 #define EXFUN(name, proto)              name()
 157 #define DEFUN(name, arglist, args)      name arglist args;
 158 #define DEFUN_VOID(name)                name()
 159 #endif /* ! IN_GCC */
 160
 161 #endif  /* ANSI C.  */
 162
 163
 164 /* Using MACRO(x,y) in cpp #if conditionals does not work with some
 165    older preprocessors.  Thus we can't define something like this:
 166
 167 #define HAVE_GCC_VERSION(MAJOR, MINOR) \
 168   (__GNUC__ > (MAJOR) || (__GNUC__ == (MAJOR) && __GNUC_MINOR__ >= (MINOR)))
 169
 170 and then test "#if HAVE_GCC_VERSION(2,7)".
 171
 172 So instead we use the macro below and test it against specific values.  */
 173
 174 /* This macro simplifies testing whether we are using gcc, and if it
 175    is of a particular minimum version. (Both major & minor numbers are
 176    significant.)  This macro will evaluate to 0 if we are not using
 177    gcc at all.  */
 178 #ifndef GCC_VERSION
 179 #define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__)
 180 #endif /* GCC_VERSION */
 181
 182 /* Define macros for some gcc attributes.  This permits us to use the
 183    macros freely, and know that they will come into play for the
 184    version of gcc in which they are supported.  */
 185
 186 #if (GCC_VERSION < 2007)
 187 # define __attribute__(x)
 188 #endif
 189
 190 /* Attributes on labels were valid as of gcc 2.93. */
 191 #ifndef ATTRIBUTE_UNUSED_LABEL
 192 # if (GCC_VERSION >= 2093)
 193 #  define ATTRIBUTE_UNUSED_LABEL ATTRIBUTE_UNUSED
 194 # else
 195 #  define ATTRIBUTE_UNUSED_LABEL
 196 # endif /* GNUC >= 2.93 */
 197 #endif /* ATTRIBUTE_UNUSED_LABEL */
 198
 199 #ifndef ATTRIBUTE_UNUSED
 200 #define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
 201 #endif /* ATTRIBUTE_UNUSED */
 202
 203 #ifndef ATTRIBUTE_NORETURN
 204 #define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__))
 205 #endif /* ATTRIBUTE_NORETURN */
 206
 207 #ifndef ATTRIBUTE_PRINTF
 208 #define ATTRIBUTE_PRINTF(m, n) __attribute__ ((__format__ (__printf__, m, n)))
 209 #define ATTRIBUTE_PRINTF_1 ATTRIBUTE_PRINTF(1, 2)
 210 #define ATTRIBUTE_PRINTF_2 ATTRIBUTE_PRINTF(2, 3)
 211 #define ATTRIBUTE_PRINTF_3 ATTRIBUTE_PRINTF(3, 4)
 212 #define ATTRIBUTE_PRINTF_4 ATTRIBUTE_PRINTF(4, 5)
 213 #define ATTRIBUTE_PRINTF_5 ATTRIBUTE_PRINTF(5, 6)
 214 #endif /* ATTRIBUTE_PRINTF */
 215
 216 #endif  /* ansidecl.h   */