cleanup const generics FIXME

This commit is contained in:
lcnr
2021-09-01 11:41:06 +02:00
parent 608b5e1c20
commit fc2a2650e2
@@ -820,10 +820,10 @@ fn visit_ty(&mut self, t: Ty<'tcx>) -> ControlFlow<Self::BreakTy> {
}
}
fn visit_const(&mut self, ct: &ty::Const<'tcx>) -> ControlFlow<Self::BreakTy> {
// First check if the type of this constant references `Self`.
self.visit_ty(ct.ty)?;
fn visit_unevaluated_const(
&mut self,
uv: ty::Unevaluated<'tcx>,
) -> ControlFlow<Self::BreakTy> {
// Constants can only influence object safety if they reference `Self`.
// This is only possible for unevaluated constants, so we walk these here.
//
@@ -837,7 +837,7 @@ fn visit_const(&mut self, ct: &ty::Const<'tcx>) -> ControlFlow<Self::BreakTy> {
// This shouldn't really matter though as we can't really use any
// constants which are not considered const evaluatable.
use rustc_middle::mir::abstract_const::Node;
if let Ok(Some(ct)) = AbstractConst::from_const(self.tcx, ct) {
if let Ok(Some(ct)) = AbstractConst::new(self.tcx, uv.shrink()) {
const_evaluatable::walk_abstract_const(self.tcx, ct, |node| match node.root() {
Node::Leaf(leaf) => {
let leaf = leaf.subst(self.tcx, ct.substs);
@@ -852,31 +852,6 @@ fn visit_const(&mut self, ct: &ty::Const<'tcx>) -> ControlFlow<Self::BreakTy> {
ControlFlow::CONTINUE
}
}
fn visit_predicate(&mut self, pred: ty::Predicate<'tcx>) -> ControlFlow<Self::BreakTy> {
if let ty::PredicateKind::ConstEvaluatable(ct) = pred.kind().skip_binder() {
// FIXME(generic_const_exprs): We should probably deduplicate the logic for
// `AbstractConst`s here, it might make sense to change `ConstEvaluatable` to
// take a `ty::Const` instead.
use rustc_middle::mir::abstract_const::Node;
if let Ok(Some(ct)) = AbstractConst::new(self.tcx, ct) {
const_evaluatable::walk_abstract_const(self.tcx, ct, |node| match node.root() {
Node::Leaf(leaf) => {
let leaf = leaf.subst(self.tcx, ct.substs);
self.visit_const(leaf)
}
Node::Cast(_, _, ty) => self.visit_ty(ty),
Node::Binop(..) | Node::UnaryOp(..) | Node::FunctionCall(_, _) => {
ControlFlow::CONTINUE
}
})
} else {
ControlFlow::CONTINUE
}
} else {
pred.super_visit_with(self)
}
}
}
value