src/cf/c-atomic.m4

   1 AC_DEFUN([OPENAFS_C_ATOMIC_CHECKS], [
   2 AC_CACHE_CHECK([if compiler has __sync_add_and_fetch],
   3     [ac_cv_sync_fetch_and_add],
   4     [AC_LINK_IFELSE(
   5       [AC_LANG_PROGRAM(
   6         [[]],
   7         [[int var; return __sync_add_and_fetch(&var, 1);]])],
   8       [ac_cv_sync_fetch_and_add=yes],
   9       [ac_cv_sync_fetch_and_add=no])
  10 ])
  11 AS_IF([test "$ac_cv_sync_fetch_and_add" = "yes"],
  12       [AC_DEFINE(HAVE_SYNC_FETCH_AND_ADD, 1,
  13           [define if your C compiler has __sync_add_and_fetch])])
  14 ])