diff --git a/libcxx/src/random.cpp b/libcxx/src/random.cpp
--- a/libcxx/src/random.cpp
+++ b/libcxx/src/random.cpp
@@ -8,7 +8,7 @@
 
 #include <__config>
 
-#if defined(_LIBCPP_USING_WIN32_RANDOM)
+#if defined(_LIBCPP_WIN32API)
     // Must be defined before including stdlib.h to enable rand_s().
 #   define _CRT_RAND_S
 #endif // defined(_LIBCPP_USING_WIN32_RANDOM)