Missing coercion site in arguments to MethodCallExpr

[philberty]

I tried this code: https://godbolt.org/z/h7zon91Kf

extern "C" {
    fn printf(s: *const i8, ...);
}

struct Foo(i32);
trait Bar {
    fn baz(&self);
    // { dg-warning "unused name" "" { target *-*-* } .-1 }
}

impl Bar for Foo {
    fn baz(&self) {
        // { dg-warning "unused name" "" { target *-*-* } .-1 }
        unsafe {
            let a = "%i\n\0";
            let b = a as *const str;
            let c = b as *const i8;

            printf(c, self.0);
        }
    }
}

struct S;
impl S {
    fn dynamic_dispatch(self, t: &dyn Bar) {
        t.baz();
    }
}

pub fn main() -> i32 {
    let a;
    a = &Foo(123);

    let b;
    b = S;

    b.dynamic_dispatch(a);

    0
}

I expected to see this happen: the argument of 'a' to the dynamic_dispatch method to be coerced into a dynamic object with a vtable

Instead, this happened: the argument of 'a' was passed without the implicit conversion required

Meta

• What version of Rust GCC were you using, git sha if possible. 649e3e0