error: expected a pattern, found an expression
  --> $DIR/issue-24197.rs:2:9
   |
LL |     let buf[0] = 0;
   |         ^^^^^^ not a pattern
   |
   = note: arbitrary expressions are not allowed in patterns: <https://doc.rust-lang.org/book/ch18-00-patterns.html>

error: aborting due to 1 previous error