diff --git a/src/util.h b/src/util.h
index e210b3a..2715803 100644
--- a/src/util.h
+++ b/src/util.h
@@ -31,7 +31,7 @@ typedef intptr_t ssize_t;
 #define inline __inline
 #endif
 
-#if !defined(static_assert) && !defined(_MSC_VER)
+#if (defined(__clang__) || defined(__GNUC__)) && !defined(static_assert)
 /* Polyfill `static_assert` for some versions of clang and gcc. */
 #define static_assert(condition, message) typedef __attribute__( \
     (__unused__)) int __static_assert_##__LINE__[(condition) ? 1 : -1];