diff --git a/include/rapidjson/internal/biginteger.h b/include/rapidjson/internal/biginteger.h
index a31c8a8..8eb87c7 100644
--- a/include/rapidjson/internal/biginteger.h
+++ b/include/rapidjson/internal/biginteger.h
@@ -17,7 +17,7 @@
 
 #include "../rapidjson.h"
 
-#if defined(_MSC_VER) && !__INTEL_COMPILER && defined(_M_AMD64)
+#if defined(_MSC_VER) && !defined(__INTEL_COMPILER) && defined(_M_AMD64)
 #include <intrin.h> // for _umul128
 #pragma intrinsic(_umul128)
 #endif