diff --git a/lib/memdebug.h b/lib/memdebug.h
index f2ebd60376..0493bf61bc 100644
--- a/lib/memdebug.h
+++ b/lib/memdebug.h
@@ -183,6 +183,7 @@ CURL_EXTERN ALLOC_FUNC
 #define fopen(file,mode) curl_dbg_fopen(file,mode,__LINE__,__FILE__)
 #undef fdopen
 #define fdopen(file,mode) curl_dbg_fdopen(file,mode,__LINE__,__FILE__)
+#undef fclose
 #define fclose(file) curl_dbg_fclose(file,__LINE__,__FILE__)
 
 #endif /* CURLDEBUG */