dnl 'extern inline' a la ISO C99.

dnl Copyright 2012-2014 Free Software Foundation, Inc.

dnl This file is free software; the Free Software Foundation

dnl gives unlimited permission to copy and/or distribute it,

dnl with or without modifications, as long as this notice is preserved.

AC_DEFUN([gl_EXTERN_INLINE],

[

  AH_VERBATIM([extern_inline],

[/* Please see the Gnulib manual for how to use these macros.

   Suppress extern inline with HP-UX cc, as it appears to be broken; see

   <http://lists.gnu.org/archive/html/bug-texinfo/2013-02/msg00030.html>.

   Suppress extern inline with Sun C in standards-conformance mode, as it

   mishandles inline functions that call each other.  E.g., for 'inline void f

   (void) { } inline void g (void) { f (); }', c99 incorrectly complains

   'reference to static identifier "f" in extern inline function'.

   This bug was observed with Sun C 5.12 SunOS_i386 2011/11/16.

   Suppress the use of extern inline on problematic Apple configurations.

   OS X 10.8 and earlier mishandle it; see, e.g.,

   <http://lists.gnu.org/archive/html/bug-gnulib/2012-12/msg00023.html>.

   OS X 10.9 has a macro __header_inline indicating the bug is fixed for C and

   for clang but remains for g++; see <http://trac.macports.org/ticket/41033>.

   Perhaps Apple will fix this some day.  */

#if (defined __APPLE__ \

     && (defined __header_inline \

         ? (defined __cplusplus && defined __GNUC_STDC_INLINE__ \

            && ! defined __clang__) \

         : ((! defined _DONT_USE_CTYPE_INLINE_ \

             && (defined __GNUC__ || defined __cplusplus)) \

            || (defined _FORTIFY_SOURCE && 0 < _FORTIFY_SOURCE \

                && defined __GNUC__ && ! defined __cplusplus))))

# define _GL_EXTERN_INLINE_APPLE_BUG

#endif

#if ((__GNUC__ \

      ? defined __GNUC_STDC_INLINE__ && __GNUC_STDC_INLINE__ \

      : (199901L <= __STDC_VERSION__ \

         && !defined __HP_cc \

         && !(defined __SUNPRO_C && __STDC__))) \

     && !defined _GL_EXTERN_INLINE_APPLE_BUG)

# define _GL_INLINE inline

# define _GL_EXTERN_INLINE extern inline

# define _GL_EXTERN_INLINE_IN_USE

#elif (2 < __GNUC__ + (7 <= __GNUC_MINOR__) && !defined __STRICT_ANSI__ \

       && !defined _GL_EXTERN_INLINE_APPLE_BUG)

# if defined __GNUC_GNU_INLINE__ && __GNUC_GNU_INLINE__

   /* __gnu_inline__ suppresses a GCC 4.2 diagnostic.  */

#  define _GL_INLINE extern inline __attribute__ ((__gnu_inline__))

# else

#  define _GL_INLINE extern inline

# endif

# define _GL_EXTERN_INLINE extern

# define _GL_EXTERN_INLINE_IN_USE

#else

# define _GL_INLINE static _GL_UNUSED

# define _GL_EXTERN_INLINE static _GL_UNUSED

#endif

#if 4 < __GNUC__ + (6 <= __GNUC_MINOR__)

# if defined __GNUC_STDC_INLINE__ && __GNUC_STDC_INLINE__

#  define _GL_INLINE_HEADER_CONST_PRAGMA

# else

#  define _GL_INLINE_HEADER_CONST_PRAGMA \

     _Pragma ("GCC diagnostic ignored \"-Wsuggest-attribute=const\"")

# endif

  /* Suppress GCC's bogus "no previous prototype for 'FOO'"

     and "no previous declaration for 'FOO'"  diagnostics,

     when FOO is an inline function in the header; see

     <http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54113>.  */

# define _GL_INLINE_HEADER_BEGIN \

    _Pragma ("GCC diagnostic push") \

    _Pragma ("GCC diagnostic ignored \"-Wmissing-prototypes\"") \

    _Pragma ("GCC diagnostic ignored \"-Wmissing-declarations\"") \

    _GL_INLINE_HEADER_CONST_PRAGMA

# define _GL_INLINE_HEADER_END \

    _Pragma ("GCC diagnostic pop")

#else

# define _GL_INLINE_HEADER_BEGIN

# define _GL_INLINE_HEADER_END

#endif])

])