error: unreachable statement
  --> $DIR/issue-2150.rs:8:5
   |
LL |     panic!();
   |     --------- any code following this expression is unreachable
LL |     for x in &v { i += 1; }
   |     ^^^^^^^^^^^^^^^^^^^^^^^ unreachable statement
   |
note: lint level defined here
  --> $DIR/issue-2150.rs:1:9
   |
LL | #![deny(unreachable_code)]
   |         ^^^^^^^^^^^^^^^^
   = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)

error: aborting due to previous error