m4/c_attribute.m4

   1 #
   2 # Check for supported __attribute__ features
   3 #
   4 # AC_C_ATTRIBUTE(FEATURE, [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])
   5 #
   6 AC_DEFUN([AC_C_ATTRIBUTE],
   7 [AS_VAR_PUSHDEF([CACHEVAR], [ax_cv_c_attribute_$1])dnl
   8 AC_CACHE_CHECK([for  __attribute__ (($1))],
   9   CACHEVAR,[
  10   AC_COMPILE_IFELSE([AC_LANG_PROGRAM([],
  11     [[ void foo(void) __attribute__ (($1)); ]])],
  12     [AS_VAR_SET(CACHEVAR, [yes])],
  13     [AS_VAR_SET(CACHEVAR, [no])])])
  14 AS_VAR_IF(CACHEVAR,yes,
  15   [m4_default([$2], :)],
  16   [m4_default([$3], :)])
  17 AS_VAR_POPDEF([CACHEVAR])dnl
  18 ])dnl