src/cf/c-pragma.m4

   1 dnl
   2 dnl Test for _Pragma and how we need to use it
   3 dnl
   4 AC_DEFUN([OPENAFS_C_PRAGMA_TAUTOLOGICAL_POINTER_COMPARE],[
   5 AC_MSG_CHECKING(for _Pragma recognition of -Wtautological-pointer-compare)
   6 AC_CACHE_VAL(ac_cv__Pragma_tautological_pointer_compare, [
   7 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
   8 _Pragma("clang diagnostic error \"-Wunknown-pragmas\"")
   9 _Pragma("clang diagnostic ignored \"-Wtautological-pointer-compare\"")
  10
  11 void func(void)
  12 {
  13         return;
  14 }
  15 ]])],
  16 [ac_cv__Pragma_tautological_pointer_compare=yes],
  17 [ac_cv__Pragma_tautological_pointer_compare=no])])
  18 AC_MSG_RESULT($ac_cv__Pragma_tautological_pointer_compare)
  19 ])
  20
  21 AC_DEFUN([_OPENAFS_C_PRAGMA], [
  22 AC_MSG_CHECKING(for _Pragma)
  23 AC_CACHE_VAL(ac_cv__Pragma, [
  24 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
  25 _Pragma("")
  26
  27 void func(void)
  28 {
  29         return;
  30 }
  31 ]])],
  32 [ac_cv__Pragma=yes],
  33 [ac_cv__Pragma=no])])
  34 AC_MSG_RESULT($ac_cv__Pragma)])
  35
  36 AC_DEFUN([OPENAFS_C_PRAGMA], [
  37 _OPENAFS_C_PRAGMA
  38 if test "$ac_cv__Pragma" = "yes"; then
  39   AC_DEFINE(HAVE__PRAGMA, 1, [define if your compiler has _Pragma])
  40   OPENAFS_C_PRAGMA_TAUTOLOGICAL_POINTER_COMPARE
  41   if test "$ac_cv__Pragma_tautological_pointer_compare" = "yes"; then
  42     AC_DEFINE(HAVE__PRAGMA_TAUTOLOGICAL_POINTER_COMPARE, 1,
  43       [define if your compiler has _Pragma and recognizes -Wtautological-pointer-compare])
  44   fi
  45 fi
  46 ])