m4/extern-inline.m4

   1 dnl 'extern inline' a la ISO C99.
   2
   3 dnl Copyright 2012 Free Software Foundation, Inc.
   4 dnl This file is free software; the Free Software Foundation
   5 dnl gives unlimited permission to copy and/or distribute it,
   6 dnl with or without modifications, as long as this notice is preserved.
   7
   8 AC_DEFUN([gl_EXTERN_INLINE],
   9 [
  10   AC_REQUIRE([AC_C_INLINE])
  11   AH_VERBATIM([extern_inline],
  12 [/* _GL_INLINE is a portable alternative to ISO C99 plain 'inline'.
  13    _GL_EXTERN_INLINE is a portable alternative to 'extern inline'.
  14    _GL_INLINE_HEADER_BEGIN contains useful stuff to put
  15      in an include file, before uses of _GL_INLINE.
  16      It suppresses GCC's bogus "no previous prototype for 'FOO'" diagnostic,
  17      when FOO is an inline function in the header; see
  18      <http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54113>.
  19    _GL_INLINE_HEADER_END contains useful stuff to put
  20      in the same include file, after uses of _GL_INLINE.  */
  21 #if (__GNUC__ \
  22      ? defined __GNUC_STDC_INLINE__ && __GNUC_STDC_INLINE__ \
  23      : 199901L <= __STDC_VERSION__)
  24 # define _GL_INLINE inline
  25 # define _GL_EXTERN_INLINE extern inline
  26 #elif 2 < __GNUC__ + (7 <= __GNUC_MINOR__)
  27 # if __GNUC_GNU_INLINE__
  28    /* __gnu_inline__ suppresses a GCC 4.2 diagnostic.  */
  29 #  define _GL_INLINE extern inline __attribute__ ((__gnu_inline__))
  30 # else
  31 #  define _GL_INLINE extern inline
  32 # endif
  33 # define _GL_EXTERN_INLINE extern
  34 #else
  35 # define _GL_INLINE static inline
  36 # define _GL_EXTERN_INLINE static inline
  37 #endif
  38
  39 #if 4 < __GNUC__ + (6 <= __GNUC_MINOR__)
  40 # if defined __GNUC_STDC_INLINE__ && __GNUC_STDC_INLINE__
  41 #  define _GL_INLINE_HEADER_CONST_PRAGMA
  42 # else
  43 #  define _GL_INLINE_HEADER_CONST_PRAGMA \
  44      _Pragma ("GCC diagnostic ignored \"-Wsuggest-attribute=const\"")
  45 # endif
  46 # define _GL_INLINE_HEADER_BEGIN \
  47     _Pragma ("GCC diagnostic push") \
  48     _Pragma ("GCC diagnostic ignored \"-Wmissing-prototypes\"") \
  49     _Pragma ("GCC diagnostic ignored \"-Wmissing-declarations\"") \
  50     _GL_INLINE_HEADER_CONST_PRAGMA
  51 # define _GL_INLINE_HEADER_END \
  52     _Pragma ("GCC diagnostic pop")
  53 #else
  54 # define _GL_INLINE_HEADER_BEGIN
  55 # define _GL_INLINE_HEADER_END
  56 #endif])
  57 ])