m4/extern-inline.m4

   1 dnl 'extern inline' a la ISO C99.
   2
   3 dnl Copyright 2012-2013 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   AH_VERBATIM([extern_inline],
  11 [/* _GL_INLINE is a portable alternative to ISO C99 plain 'inline'.
  12    _GL_EXTERN_INLINE is a portable alternative to 'extern inline'.
  13    _GL_INLINE_HEADER_BEGIN contains useful stuff to put
  14      in an include file, before uses of _GL_INLINE.
  15      It suppresses GCC's bogus "no previous prototype for 'FOO'" diagnostic,
  16      when FOO is an inline function in the header; see
  17      <http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54113>.
  18    _GL_INLINE_HEADER_END contains useful stuff to put
  19      in the same include file, after uses of _GL_INLINE.
  20
  21    Suppress extern inline with HP-UX cc, as it appears to be broken; see
  22    <http://lists.gnu.org/archive/html/bug-texinfo/2013-02/msg00030.html>.
  23
  24    Suppress the use of extern inline on Apple's platforms,
  25    as Libc-825.25 (2012-09-19) is incompatible with it; see
  26    <http://lists.gnu.org/archive/html/bug-gnulib/2012-12/msg00023.html>.
  27    Perhaps Apple will fix this some day.  */
  28 #if ((__GNUC__ \
  29       ? defined __GNUC_STDC_INLINE__ && __GNUC_STDC_INLINE__ \
  30       : 199901L <= __STDC_VERSION__ && !defined __HP_cc) \
  31      && !defined __APPLE__)
  32 # define _GL_INLINE inline
  33 # define _GL_EXTERN_INLINE extern inline
  34 #elif 2 < __GNUC__ + (7 <= __GNUC_MINOR__) && !defined __APPLE__
  35 # if __GNUC_GNU_INLINE__
  36    /* __gnu_inline__ suppresses a GCC 4.2 diagnostic.  */
  37 #  define _GL_INLINE extern inline __attribute__ ((__gnu_inline__))
  38 # else
  39 #  define _GL_INLINE extern inline
  40 # endif
  41 # define _GL_EXTERN_INLINE extern
  42 #else
  43 # define _GL_INLINE static _GL_UNUSED
  44 # define _GL_EXTERN_INLINE static _GL_UNUSED
  45 #endif
  46
  47 #if 4 < __GNUC__ + (6 <= __GNUC_MINOR__)
  48 # if defined __GNUC_STDC_INLINE__ && __GNUC_STDC_INLINE__
  49 #  define _GL_INLINE_HEADER_CONST_PRAGMA
  50 # else
  51 #  define _GL_INLINE_HEADER_CONST_PRAGMA \
  52      _Pragma ("GCC diagnostic ignored \"-Wsuggest-attribute=const\"")
  53 # endif
  54 # define _GL_INLINE_HEADER_BEGIN \
  55     _Pragma ("GCC diagnostic push") \
  56     _Pragma ("GCC diagnostic ignored \"-Wmissing-prototypes\"") \
  57     _Pragma ("GCC diagnostic ignored \"-Wmissing-declarations\"") \
  58     _GL_INLINE_HEADER_CONST_PRAGMA
  59 # define _GL_INLINE_HEADER_END \
  60     _Pragma ("GCC diagnostic pop")
  61 #else
  62 # define _GL_INLINE_HEADER_BEGIN
  63 # define _GL_INLINE_HEADER_END
  64 #endif])
  65 ])