rustc_typeck: fix the generics for (const-generic) N expression in e.g. [T; N].

This commit is contained in:
Eduard-Mihai Burtescu 2019-08-12 20:23:07 +03:00
parent 7d9af83ffc
commit f4aa00b71d

View File

@ -900,6 +900,20 @@ fn generics_of(tcx: TyCtxt<'_>, def_id: DefId) -> &ty::Generics {
let parent_id = tcx.hir().get_parent_item(hir_id);
Some(tcx.hir().local_def_id(parent_id))
}
// FIXME(#43408) enable this in all cases when we get lazy normalization.
Node::AnonConst(&anon_const) => {
// HACK(eddyb) this provides the correct generics when the workaround
// for a const parameter `AnonConst` is being used elsewhere, as then
// there won't be the kind of cyclic dependency blocking #43408.
let expr = &tcx.hir().body(anon_const.body).value;
let icx = ItemCtxt::new(tcx, def_id);
if AstConv::const_param_def_id(&icx, expr).is_some() {
let parent_id = tcx.hir().get_parent_item(hir_id);
Some(tcx.hir().local_def_id(parent_id))
} else {
None
}
}
Node::Expr(&hir::Expr {
node: hir::ExprKind::Closure(..),
..