diff --git a/target-alpha/op_helper.c b/target-alpha/op_helper.c
index 6c2ae2061f..36f4f6d3b8 100644
--- a/target-alpha/op_helper.c
+++ b/target-alpha/op_helper.c
@@ -904,10 +904,11 @@ uint64_t helper_cmptun (uint64_t a, uint64_t b)
     fa = t_to_float64(a);
     fb = t_to_float64(b);
 
-    if (float64_is_quiet_nan(fa) || float64_is_quiet_nan(fb))
+    if (float64_unordered_quiet(fa, fb, &FP_STATUS)) {
         return 0x4000000000000000ULL;
-    else
+    } else {
         return 0;
+    }
 }
 
 uint64_t helper_cmpteq(uint64_t a, uint64_t b)