diff --git a/src/lock.h b/src/lock.h
index cd4dfa70..14fcd5d9 100644
--- a/src/lock.h
+++ b/src/lock.h
@@ -86,8 +86,9 @@ typedef pthread_mutex_t Lock;
 
 #else
 
-
+#define WIN32_LEAN_AND_MEAN
 #include <windows.h>
+#undef WIN32_LEAN_AND_MEAN
 
 typedef CRITICAL_SECTION Lock;
 #  define lock_init(x, y) InitializeCriticalSection(x)