rust/src/test/ui/wf/wf-static-method.rs
2021-05-21 10:16:53 -04:00

56 lines
1.5 KiB
Rust

// check that static methods don't get to assume their trait-ref
// is well-formed.
// FIXME(#27579): this is just a bug. However, our checking with
// static inherent methods isn't quite working - need to
// fix that before removing the check.
trait Foo<'a, 'b, T>: Sized {
fn make_me() -> Self { loop {} }
fn static_evil(u: &'b u32) -> &'a u32;
}
struct Evil<'a, 'b: 'a>(Option<&'a &'b ()>);
impl<'a, 'b> Foo<'a, 'b, Evil<'a, 'b>> for () {
fn make_me() -> Self { }
fn static_evil(u: &'b u32) -> &'a u32 {
u //~ ERROR E0312
}
}
struct IndirectEvil<'a, 'b: 'a>(Option<&'a &'b ()>);
impl<'a, 'b> Foo<'a, 'b, ()> for IndirectEvil<'a, 'b> {
fn make_me() -> Self { IndirectEvil(None) }
fn static_evil(u: &'b u32) -> &'a u32 {
let me = Self::make_me(); //~ ERROR lifetime bound not satisfied
loop {} // (`me` could be used for the lifetime transmute).
}
}
impl<'a, 'b> Evil<'a, 'b> {
fn inherent_evil(u: &'b u32) -> &'a u32 {
u //~ ERROR E0312
}
}
// while static methods don't get to *assume* this, we still
// *check* that they hold.
fn evil<'a, 'b>(b: &'b u32) -> &'a u32 {
<()>::static_evil(b) //~ ERROR cannot infer an appropriate lifetime
}
fn indirect_evil<'a, 'b>(b: &'b u32) -> &'a u32 {
<IndirectEvil>::static_evil(b)
//~^ ERROR cannot infer an appropriate lifetime
}
fn inherent_evil<'a, 'b>(b: &'b u32) -> &'a u32 {
<Evil>::inherent_evil(b)
//~^ ERROR cannot infer an appropriate lifetime
}
fn main() {}