bjoernager/rust
bjoernager/rust
1
Fork 0
Code Issues Pull requests Activity

also handle it in evaluate

Browse source
This commit is contained in:
Boxy 2022-11-15 23:11:30 +00:00 • committed by kadmin
parent 0ae3c5c609
commit fd271ffe28
1 changed files with 51 additions and 24 deletions
Download patch file Download diff file Expand all files Collapse all files

75
compiler/rustc_trait_selection/src/traits/select/mod.rs
View file

@ -662,32 +662,59 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
tcx.features().generic_const_exprs,
"`ConstEquate` without a feature gate: {c1:?} {c2:?}",
);
debug!(?c1, ?c2, "evaluate_predicate_recursively: equating consts");
// FIXME: we probably should only try to unify abstract constants
// if the constants depend on generic parameters.
//
// Let's just see where this breaks :shrug:
if let (ty::ConstKind::Unevaluated(_), ty::ConstKind::Unevaluated(_)) =
(c1.kind(), c2.kind())
{
if let Ok(Some(a)) = tcx.expand_abstract_consts(c1)
&& let Ok(Some(b)) = tcx.expand_abstract_consts(c2)
&& a.ty() == b.ty()
&& let Ok(new_obligations) = self
.infcx
.at(&obligation.cause, obligation.param_env)
.eq(a, b)
{
let mut obligations = new_obligations.obligations;
self.add_depth(
obligations.iter_mut(),
obligation.recursion_depth,
);
return self.evaluate_predicates_recursively(
previous_stack,
obligations.into_iter(),
);
let c1 =
if let Ok(Some(a)) = tcx.expand_abstract_consts(c1) { a } else { c1 };
let c2 =
if let Ok(Some(b)) = tcx.expand_abstract_consts(c2) { b } else { c2 };
debug!(
"evalaute_predicate_recursively: equating consts:\nc1= {:?}\nc2= {:?}",
c1, c2
);
use rustc_hir::def::DefKind;
use ty::ConstKind::Unevaluated;
match (c1.kind(), c2.kind()) {
(Unevaluated(a), Unevaluated(b))
if a.def.did == b.def.did
&& tcx.def_kind(a.def.did) == DefKind::AssocConst =>
{
if let Ok(new_obligations) = self
.infcx
.at(&obligation.cause, obligation.param_env)
.trace(c1, c2)
.eq(a.substs, b.substs)
{
let mut obligations = new_obligations.obligations;
self.add_depth(
obligations.iter_mut(),
obligation.recursion_depth,
);
return self.evaluate_predicates_recursively(
previous_stack,
obligations.into_iter(),
);
}
}
(_, Unevaluated(_)) | (Unevaluated(_), _) => (),
(_, _) => {
if let Ok(new_obligations) = self
.infcx
.at(&obligation.cause, obligation.param_env)
.eq(c1, c2)
{
let mut obligations = new_obligations.obligations;
self.add_depth(
obligations.iter_mut(),
obligation.recursion_depth,
);
return self.evaluate_predicates_recursively(
previous_stack,
obligations.into_iter(),
);
}
}
}
}