rnMethodBind cls sig_fn gen_tyvars (L loc (FunBind { fun_id = name, fun_infix = inf,
fun_matches = MatchGroup matches _ }))
= setSrcSpan loc $ do
- sel_name <- lookupInstDeclBndr cls name
+ sel_name <- wrapLocM (lookupInstDeclBndr cls) name
let plain_name = unLoc sel_name
-- We use the selector name as the binder