Can't link to multiple versions of the same crate

[brson]

I'll be checking this in under run-pass/crateresolve2.rs

// xfail-test
// aux-build:crateresolve-1.rs
// aux-build:crateresolve-2.rs
// aux-build:crateresolve-3.rs

mod a {
    use crateresolve(vers = "0.1");
    fn f() { assert crateresolve::f() == 10; }
}

mod b {
    use crateresolve(vers = "0.2");
    fn f() { assert crateresolve::f() == 20; }
}

mod c {
    use crateresolve(vers = "0.3");
    fn f() { assert crateresolve::f() == 30; }
}

fn main() {
    a::f();
    b::f();
    c::f();
}

Some of the errors make me think that #1706 is part of the problem.

[lht]

I took a look on this. It seems the problem is version is not encoded in exported symbols, yet. (There is a FIXME on back::link::exported_name). Function crateresolve::f() is exported as _ZN1f16E regardless which version the library is.

And when translating the call expression, trans::base::get_extern_const always uses the first symbol it found, here f() with vesion 1.0.

[lht]

Then I guess this depends on #456.

[brson]

Symbols now have both the meta hash and crate version. This works now.