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// check that static methods can assume their trait-ref is well-formed.
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
}
}
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();
loop {} // (`me` could be used for the lifetime transmute).
}
}
impl<'a, 'b> Evil<'a, 'b> {
fn inherent_evil(u: &'b u32) -> &'a u32 {
u
}
}
// while static methods can *assume* this, we should still
// *check* that it holds at the use site.
fn evil<'a, 'b>(b: &'b u32) -> &'a u32 {
<()>::static_evil(b)
//~^ ERROR lifetime may not live long enough
}
fn indirect_evil<'a, 'b>(b: &'b u32) -> &'a u32 {
<IndirectEvil>::static_evil(b)
//~^ ERROR lifetime may not live long enough
}
fn inherent_evil<'a, 'b>(b: &'b u32) -> &'a u32 {
<Evil>::inherent_evil(b)
//~^ ERROR lifetime may not live long enough
}
fn main() {}
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