diff --git a/src/libs/compat/freebsd_iflib/nvlist.c b/src/libs/compat/freebsd_iflib/nvlist.c
index 0101d8c9e8..d228b0616d 100644
--- a/src/libs/compat/freebsd_iflib/nvlist.c
+++ b/src/libs/compat/freebsd_iflib/nvlist.c
@@ -1476,6 +1476,10 @@ nvlist_add_nvpair(nvlist_t *nvl, const nvpair_t *nvp)
 	nvpair_insert(&nvl->nvl_head, newnvp, nvl);
 }
 
+void
+nvlist_add_stringv(nvlist_t *nvl, const char *name, const char *valuefmt,
+    va_list valueap);
+
 void
 nvlist_add_stringf(nvlist_t *nvl, const char *name, const char *valuefmt, ...)
 {