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#![allow(dead_code)]
// Test that we relate the type of the fn type to the type of the fn
// ptr when doing a `ReifyFnPointer` cast.
//
// This test is a bit tortured, let me explain:
//
// The `where 'a: 'a` clause here ensures that `'a` is early bound,
// which is needed below to ensure that this test hits the path we are
// concerned with.
fn foo<'a>(x: &'a u32) -> &'a u32
where
'a: 'a,
{
panic!()
}
fn bar<'a>(x: &'a u32) -> &'static u32 {
// Here, the type of `foo` is `typeof(foo::<'x>)` for some fresh variable `'x`.
// During NLL region analysis, this will get renumbered to `typeof(foo::<'?0>)`
// where `'?0` is a new region variable.
//
// (Note that if `'a` on `foo` were late-bound, the type would be
// `typeof(foo)`, which would interact differently with because
// the renumbering later.)
//
// This type is then coerced to a fn type `fn(&'?1 u32) -> &'?2
// u32`. Here, the `'?1` and `'?2` will have been created during
// the NLL region renumbering.
//
// The MIR type checker must therefore relate `'?0` to `'?1` and `'?2`
// as part of checking the `ReifyFnPointer`.
let f: fn(_) -> _ = foo;
f(x)
//~^ ERROR lifetime may not live long enough
}
fn main() {}
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