1 error[E0631]: type mismatch in closure arguments
2 --> $DIR/unboxed-closures-vtable-mismatch.rs:16:24
4 LL | let f = to_fn_mut(|x: usize, y: isize| -> isize { (x as isize) + y });
5 | ----------------------------- found signature of `fn(usize, isize) -> _`
7 LL | let z = call_it(3, f);
8 | ------- ^ expected signature of `fn(isize, isize) -> _`
10 | required by a bound introduced by this call
12 note: required by a bound in `call_it`
13 --> $DIR/unboxed-closures-vtable-mismatch.rs:7:14
15 LL | fn call_it<F:FnMut(isize,isize)->isize>(y: isize, mut f: F) -> isize {
16 | ^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `call_it`
18 error: aborting due to previous error
20 For more information about this error, try `rustc --explain E0631`.