Crate metadata matching should consider a target architecture

[alexcrichton]

Let's say you have a compiler for both 32-bit linux and 64-bit linux targets. You compile a library which links against the 32-bit libstd, but you then compile a 64-bit library which links against the 32-bit library you generated. This generates a mismatch between the 32-bit libstd and the 64-bit libstd metadata which you're looking at.

Right now rustc dies horribly about an unknown node ID, but it would be much more graceful if rustc inserted the target architecture into the metadata of the crate attributes and then matched against it as well.

[huonw]

Do you know how one might drive rustc to do the "compile a 64-bit library which links against the 32-bit library you generated" step?

(triage.)

[huonw]

Ah, I'm just silly; it's simple:

// lib10814.rs
#![no_std]
#![crate_type = "lib"]

extern crate lib10814;

$ rustc lib10814.rs --target=i686-unknown-linux-gnu
$ rustc 10814.rs -L .
10814.rs:1:1: 1:23 error: found incorrect triple for crate `lib10814`
10814.rs:1 extern crate lib10814;
           ^~~~~~~~~~~~~~~~~~~~~~
10814.rs:1:1: 1:23 note: expected triple of x86_64-unknown-linux-gnu
10814.rs:1 extern crate lib10814;
           ^~~~~~~~~~~~~~~~~~~~~~
10814.rs:1:23: 1:23 note: crate `lib10814` path #1, triple i686-unknown-linux-gnu: .../triage/liblib10814.rlib
error: aborting due to previous error

So this bug is fixed, I'm adding a test now.