mirror of https://github.com/rust-lang/rust
34 lines
1.3 KiB
Rust
34 lines
1.3 KiB
Rust
//@ run-pass
|
|
// This is a regression test for the ICE from issue #10846.
|
|
//
|
|
// The original issue causing the ICE: the LUB-computations during
|
|
// type inference were encountering late-bound lifetimes, and
|
|
// asserting that such lifetimes should have already been substituted
|
|
// with a concrete lifetime.
|
|
//
|
|
// However, those encounters were occurring within the lexical scope
|
|
// of the binding for the late-bound lifetime; that is, the late-bound
|
|
// lifetimes were perfectly valid. The core problem was that the type
|
|
// folding code was over-zealously passing back all lifetimes when
|
|
// doing region-folding, when really all clients of the region-folding
|
|
// case only want to see FREE lifetime variables, not bound ones.
|
|
|
|
//@ pretty-expanded FIXME #23616
|
|
|
|
pub fn main() {
|
|
fn explicit() {
|
|
fn test<F>(_x: Option<Box<F>>) where F: FnMut(Box<dyn for<'a> FnMut(&'a isize)>) {}
|
|
test(Some(Box::new(|_f: Box<dyn for<'a> FnMut(&'a isize)>| {})));
|
|
}
|
|
|
|
// The code below is shorthand for the code above (and more likely
|
|
// to represent what one encounters in practice).
|
|
fn implicit() {
|
|
fn test<F>(_x: Option<Box<F>>) where F: FnMut(Box<dyn FnMut(& isize)>) {}
|
|
test(Some(Box::new(|_f: Box<dyn FnMut(& isize)>| {})));
|
|
}
|
|
|
|
explicit();
|
|
implicit();
|
|
}
|