diff --git a/libc/libc.map.txt b/libc/libc.map.txt
index 9d51b8d..25f647d 100644
--- a/libc/libc.map.txt
+++ b/libc/libc.map.txt
@@ -1300,6 +1300,7 @@
 LIBC_O {
   global:
     getdomainname;
+    getsubopt;
     hasmntopt;
     pthread_getname_np;
     setdomainname;