diff options
Diffstat (limited to 'compiler/rustc_middle/src/values.rs')
| -rw-r--r-- | compiler/rustc_middle/src/values.rs | 23 |
1 files changed, 17 insertions, 6 deletions
diff --git a/compiler/rustc_middle/src/values.rs b/compiler/rustc_middle/src/values.rs index f4b4c3fb0..70b98e59a 100644 --- a/compiler/rustc_middle/src/values.rs +++ b/compiler/rustc_middle/src/values.rs @@ -32,13 +32,23 @@ impl<'tcx> Value<TyCtxt<'tcx>> for ty::SymbolName<'_> { } impl<'tcx> Value<TyCtxt<'tcx>> for ty::Binder<'_, ty::FnSig<'_>> { - fn from_cycle_error(tcx: TyCtxt<'tcx>, _: &[QueryInfo]) -> Self { + fn from_cycle_error(tcx: TyCtxt<'tcx>, stack: &[QueryInfo]) -> Self { let err = tcx.ty_error(); - // FIXME(compiler-errors): It would be nice if we could get the - // query key, so we could at least generate a fn signature that - // has the right arity. + + let arity = if let Some(frame) = stack.get(0) + && frame.query.name == "fn_sig" + && let Some(def_id) = frame.query.def_id + && let Some(node) = tcx.hir().get_if_local(def_id) + && let Some(sig) = node.fn_sig() + { + sig.decl.inputs.len() + sig.decl.implicit_self.has_implicit_self() as usize + } else { + tcx.sess.abort_if_errors(); + unreachable!() + }; + let fn_sig = ty::Binder::dummy(tcx.mk_fn_sig( - [].into_iter(), + std::iter::repeat(err).take(arity), err, false, rustc_hir::Unsafety::Normal, @@ -185,7 +195,8 @@ fn find_item_ty_spans( }); if check_params && let Some(args) = path.segments.last().unwrap().args { let params_in_repr = tcx.params_in_repr(def_id); - for (i, arg) in args.args.iter().enumerate() { + // the domain size check is needed because the HIR may not be well-formed at this point + for (i, arg) in args.args.iter().enumerate().take(params_in_repr.domain_size()) { if let hir::GenericArg::Type(ty) = arg && params_in_repr.contains(i as u32) { find_item_ty_spans(tcx, ty, needle, spans, seen_representable); } |