diff --git a/libc/include/sys/fsuid.h b/libc/include/sys/fsuid.h
index 3257bc0..bc47e3d 100644
--- a/libc/include/sys/fsuid.h
+++ b/libc/include/sys/fsuid.h
@@ -33,8 +33,10 @@
 
 __BEGIN_DECLS
 
+#if 0 /* MISSING FROM BIONIC */
 extern int setfsuid(uid_t);
 extern int setfsgid(gid_t);
+#endif /* MISSING */
 
 __END_DECLS
 
diff --git a/libc/include/sys/mount.h b/libc/include/sys/mount.h
index 62c4ee2..ba88447 100644
--- a/libc/include/sys/mount.h
+++ b/libc/include/sys/mount.h
@@ -92,7 +92,10 @@
 		   const void *);
 extern int umount(const char *);
 extern int umount2(const char *, int);
+
+#if 0 /* MISSING FROM BIONIC */
 extern int pivot_root(const char *, const char *);
+#endif /* MISSING */
 
 __END_DECLS