diff --git a/crypto/compat/arc4random.h b/crypto/compat/arc4random.h
index 7af7fc1..53b5a46 100644
--- a/crypto/compat/arc4random.h
+++ b/crypto/compat/arc4random.h
@@ -15,7 +15,7 @@
 #elif defined(__sun)
 #include "arc4random_solaris.h"
 
-#elif defined(__WIN32)
+#elif defined(_WIN32)
 #include "arc4random_win.h"
 
 #else
diff --git a/include/machine/endian.h b/include/machine/endian.h
index 80b3f9c..e3120db 100644
--- a/include/machine/endian.h
+++ b/include/machine/endian.h
@@ -1,7 +1,7 @@
 #ifndef LIBCRYPTOCOMPAT_BYTE_ORDER_H_
 #define LIBCRYPTOCOMPAT_BYTE_ORDER_H_
 
-#if defined(__WIN32)
+#if defined(_WIN32)
 
 #define LITTLE_ENDIAN  1234
 #define BIG_ENDIAN 4321