diff --git a/libc/include/wchar.h b/libc/include/wchar.h
index a4e19f0..76ac02c 100644
--- a/libc/include/wchar.h
+++ b/libc/include/wchar.h
@@ -65,8 +65,11 @@
     WC_TYPE_MAX
 } wctype_t;
 
+#ifndef WCHAR_MAX
 #define  WCHAR_MAX   INT_MAX
 #define  WCHAR_MIN   INT_MIN
+#endif
+
 #define  WEOF        ((wint_t)(-1))
 
 extern wint_t            btowc(int);