diff --git a/xf86atomic.h b/xf86atomic.h
index 2d733bd5..e268d274 100644
--- a/xf86atomic.h
+++ b/xf86atomic.h
@@ -101,6 +101,8 @@ typedef struct { LIBDRM_ATOMIC_TYPE atomic; } atomic_t;
 #error libdrm requires atomic operations, please define them for your CPU/compiler.
 #endif
 
+#undef HAS_ATOMIC_OPS
+
 static inline int atomic_add_unless(atomic_t *v, int add, int unless)
 {
 	int c, old;