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//@ run-pass
pub trait NumCast: Sized {
fn from(i: i32) -> Option<Self>;
}
pub trait NumExt: PartialEq + NumCast {}
impl NumExt for f32 {}
impl NumExt for isize {}
impl NumCast for f32 {
fn from(i: i32) -> Option<f32> { Some(i as f32) }
}
impl NumCast for isize {
fn from(i: i32) -> Option<isize> { Some(i as isize) }
}
fn num_eq_one<T:NumExt>() -> T {
NumCast::from(1).unwrap()
}
pub fn main() {
num_eq_one::<isize>(); // you need to actually use the function to trigger the ICE
}
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