diff --git a/libc/bionic/net_if.cpp b/libc/bionic/net_if.cpp
index f8d73bd..db9c9ea2 100644
--- a/libc/bionic/net_if.cpp
+++ b/libc/bionic/net_if.cpp
@@ -77,7 +77,7 @@
   if_list* next;
   struct if_nameindex data;
 
-  if_list(if_list** list) {
+  explicit if_list(if_list** list) {
     // push_front onto `list`.
     next = *list;
     *list = this;