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 [/* Please see the Gnulib manual for how to use these macros.
  12
  13    Suppress extern inline with HP-UX cc, as it appears to be broken; see
  14    <http://lists.gnu.org/archive/html/bug-texinfo/2013-02/msg00030.html>.
  15
  16    Suppress extern inline with Sun C in standards-conformance mode, as it
  17    mishandles inline functions that call each other.  E.g., for 'inline void f
  18    (void) { } inline void g (void) { f (); }', c99 incorrectly complains
  19    'reference to static identifier "f" in extern inline function'.
  20    This bug was observed with Sun C 5.12 SunOS_i386 2011/11/16.
  21
  22    Suppress the use of extern inline on Apple's platforms, as Libc at least
  23    through Libc-825.26 (2013-04-09) is incompatible with it; see, e.g.,
  24    <http://lists.gnu.org/archive/html/bug-gnulib/2012-12/msg00023.html>.
  25    Perhaps Apple will fix this some day.  */
  26 #if ((__GNUC__ \
  27       ? defined __GNUC_STDC_INLINE__ && __GNUC_STDC_INLINE__ \
  28       : (199901L <= __STDC_VERSION__ \
  29          && !defined __HP_cc \
  30          && !(defined __SUNPRO_C && __STDC__))) \
  31      && !defined __APPLE__)
  32 # define _GL_INLINE inline
  33 # define _GL_EXTERN_INLINE extern inline
  34 #elif (2 < __GNUC__ + (7 <= __GNUC_MINOR__) && !defined __STRICT_ANSI__ \
  35        && !defined __APPLE__)
  36 # if __GNUC_GNU_INLINE__
  37    /* __gnu_inline__ suppresses a GCC 4.2 diagnostic.  */
  38 #  define _GL_INLINE extern inline __attribute__ ((__gnu_inline__))
  39 # else
  40 #  define _GL_INLINE extern inline
  41 # endif
  42 # define _GL_EXTERN_INLINE extern
  43 #else
  44 # define _GL_INLINE static _GL_UNUSED
  45 # define _GL_EXTERN_INLINE static _GL_UNUSED
  46 #endif
  47
  48 #if 4 < __GNUC__ + (6 <= __GNUC_MINOR__)
  49 # if defined __GNUC_STDC_INLINE__ && __GNUC_STDC_INLINE__
  50 #  define _GL_INLINE_HEADER_CONST_PRAGMA
  51 # else
  52 #  define _GL_INLINE_HEADER_CONST_PRAGMA \
  53      _Pragma ("GCC diagnostic ignored \"-Wsuggest-attribute=const\"")
  54 # endif
  55   /* Suppress GCC's bogus "no previous prototype for 'FOO'"
  56      and "no previous declaration for 'FOO'"  diagnostics,
  57      when FOO is an inline function in the header; see
  58      <http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54113>.  */
  59 # define _GL_INLINE_HEADER_BEGIN \
  60     _Pragma ("GCC diagnostic push") \
  61     _Pragma ("GCC diagnostic ignored \"-Wmissing-prototypes\"") \
  62     _Pragma ("GCC diagnostic ignored \"-Wmissing-declarations\"") \
  63     _GL_INLINE_HEADER_CONST_PRAGMA
  64 # define _GL_INLINE_HEADER_END \
  65     _Pragma ("GCC diagnostic pop")
  66 #else
  67 # define _GL_INLINE_HEADER_BEGIN
  68 # define _GL_INLINE_HEADER_END
  69 #endif])
  70 ])