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//@ compile-flags: -Znext-solver
//@ revisions: fallback constrain
//@[constrain] check-pass
// Tests that we stall the `{integer}: Foo` obligation until after we
// constrain the int type (or fallback occurs).
#![feature(negative_impls, auto_traits)]
auto trait Foo {}
impl !Foo for i32 {}
fn needs_foo(x: impl Foo) {}
fn main() {
let mut x = 0;
needs_foo(x);
//[fallback]~^ ERROR the trait bound `i32: Foo` is not satisfied
#[cfg(constrain)]
{
x = 1u64;
}
}
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