diff --git a/Grid_main.cc b/Grid_main.cc
index e122fcbe..291cde25 100644
--- a/Grid_main.cc
+++ b/Grid_main.cc
@@ -48,7 +48,7 @@ int main (int argc, char ** argv)
     simd_layout[2] = 2;
     simd_layout[3] = 2;
 #endif
-#if defined (SSE2)
+#if defined (SSE4)
     simd_layout[0] = 1;
     simd_layout[1] = 1;
     simd_layout[2] = 1;