rust/tests/ui/mir/mir-inlining/always-encode-mirs.rs

// Regression test for MIR inlining with -Zalways-encode-mir enabled in the auxiliary crate.
// Previously we inlined function not eligible for inlining which lead to linking error:
// undefined reference to `internal::S'
//
// aux-build:internal.rs
// build-pass
// compile-flags: -O
extern crate internal;

fn main() {
    println!("{}", internal::f());
}