src/test/ui/closures/coerce-unsafe-to-closure.stderr

   1 error[E0277]: expected a `FnOnce<(&str,)>` closure, found `unsafe extern "rust-intrinsic" fn(_) -> _ {transmute::<_, _>}`
   2   --> $DIR/coerce-unsafe-to-closure.rs:2:44
   3    |
   4 LL |     let x: Option<&[u8]> = Some("foo").map(std::mem::transmute);
   5    |                                        --- ^^^^^^^^^^^^^^^^^^^ call the function in a closure: `|| unsafe { /* code */ }`
   6    |                                        |
   7    |                                        required by a bound introduced by this call
   8    |
   9    = help: the trait `FnOnce<(&str,)>` is not implemented for fn item `unsafe extern "rust-intrinsic" fn(_) -> _ {transmute::<_, _>}`
  10    = note: unsafe function cannot be called generically without an unsafe block
  11 note: required by a bound in `Option::<T>::map`
  12   --> $SRC_DIR/core/src/option.rs:LL:COL
  13    |
  14 LL |         F: ~const FnOnce(T) -> U,
  15    |            ^^^^^^^^^^^^^^^^^^^^^ required by this bound in `Option::<T>::map`
  16
  17 error: aborting due to previous error
  18
  19 For more information about this error, try `rustc --explain E0277`.