diff --git a/libc/libc.map.txt b/libc/libc.map.txt
index f05e7eb..c453a38 100644
--- a/libc/libc.map.txt
+++ b/libc/libc.map.txt
@@ -1579,4 +1579,5 @@
     malloc_disable;
     malloc_enable;
     malloc_iterate;
+    mallopt;
 } LIBC_O;