diff --git a/node/Salsa20.hpp b/node/Salsa20.hpp
index bfb6d9d9..885ec003 100644
--- a/node/Salsa20.hpp
+++ b/node/Salsa20.hpp
@@ -19,6 +19,12 @@
 #define ZT_SALSA20_SSE 1
 #endif
 
+#if defined(ZT_SALSA20_SSE)
+#if !ZT_SALSA20_SSE
+#undef ZT_SALSA20_SSE
+#endif
+#endif
+
 #ifdef ZT_SALSA20_SSE
 #include <emmintrin.h>
 #endif // ZT_SALSA20_SSE