remove the "don't add _ WF obligation" hack

it doesn't seem to be necessary and is potentially harmful.
This commit is contained in:
Ariel Ben-Yehuda 2015-10-02 23:36:07 +03:00
parent e650491f20
commit c379f604f1

View file

@ -1557,21 +1557,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
pub fn to_ty(&self, ast_t: &hir::Ty) -> Ty<'tcx> {
let t = ast_ty_to_ty(self, self, ast_t);
// Generally speaking, we must check that types entered by the
// user are well-formed. This is not true for `_`, since those
// types are generated by inference. Now, you might think that
// we could as well generate a WF obligation -- but
// unfortunately that breaks code like `foo as *const _`,
// because those type variables wind up being unconstrained
// until very late. Nasty. Probably it'd be best to refactor
// that code path, but that's tricky because of
// defaults. Argh!
match ast_t.node {
hir::TyInfer => { }
_ => { self.register_wf_obligation(t, ast_t.span, traits::MiscObligation); }
}
self.register_wf_obligation(t, ast_t.span, traits::MiscObligation);
t
}