Function rustc_span::hygiene::assert_default_hashing_controls

fn assert_default_hashing_controls<CTX: HashStableContext>(ctx: &CTX, msg: &str)

Assert that the provided HashStableContext is configured with the ‘default’ HashingControls. We should always have bailed out before getting to here with a non-default mode. With this check in place, we can avoid the need to maintain separate versions of ExpnData hashes for each permutation of HashingControls settings.