check_c_source_compiles ("int main() { char l; unsigned long v; __atomic_test_and_set(&l, __ATOMIC_RELAXED); __atomic_store_n(&v, 1, __ATOMIC_RELEASE); __atomic_load_n(&v, __ATOMIC_ACQUIRE); __atomic_add_fetch(&v, 1, __ATOMIC_ACQUIRE); __atomic_sub_fetch(&v, 1, __ATOMIC_RELEASE); return 0; }" HAVE_ATOMIC_BUILTINS)

check_c_source_compiles(
  "int main() { int i, x = 0; i = __sync_add_and_fetch(&x,1); return x; }"
  HAVE_ATOMIC_BUILTINS)

check_c_source_compiles(
        "int main() { int i, x = 0; i = __sync_add_and_fetch(&x,1); return x; }"
        HAVE_ATOMIC_BUILTINS)

CHECK_C_SOURCE_COMPILES("${SYNC_BUILTINS_TEST_SOURCE}" HAVE_ATOMIC_BUILTINS)

ENDIF(NOT HAVE_ATOMIC_BUILTINS)

LIST(APPEND UCL_COMPILE_DEFS -DHAVE_ATOMIC_BUILTINS=1)

ENDIF(HAVE_ATOMIC_BUILTINS)