error: variable `X` should have a snake case name such as `x`
  --> $DIR/expr_attr_paren_order.rs:29:17
   |
LL |             let X = 0; //~ ERROR snake case name
   |                 ^
   |
note: lint level defined here
  --> $DIR/expr_attr_paren_order.rs:27:17
   |
LL |         #![deny(non_snake_case)]
   |                 ^^^^^^^^^^^^^^

error: aborting due to previous error