--- a/prelude/CATS/array.cats
+++ b/prelude/CATS/array.cats
@@ -50,12 +50,14 @@
 //
 // [stdlib.h]
 //
+#undef qsort
 extern
 void qsort
 (
   void *base, size_t nmemb, size_t size
 , int(*compar)(const void *, const void *)
 ) ; // end of [qsort]
+#undef bsearch
 extern
 void *bsearch
 (
