1 files changed, 0 insertions, 2 deletions
diff --git a/thread.c b/thread.c
index 039b858294..a8cc250239 100644
--- a/thread.c
+++ b/thread.c
@@ -4662,8 +4662,6 @@ rb_thread_shield_destroy(VALUE self)
 /* variables for recursive traversals */
 static ID recursive_key;
 
-extern const struct st_hash_type st_hashtype_num;
-
 static VALUE
 ident_hash_new(void)
 {