Stop passing empty args to check_expr_path

compiler/rustc_hir_typeck/src/expr.rs

@@ -222,7 +222,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let ty = ensure_sufficient_stack(|| match &expr.kind {
             hir::ExprKind::Path(
                 qpath @ (hir::QPath::Resolved(..) | hir::QPath::TypeRelative(..)),
-            ) => self.check_expr_path(qpath, expr, args, call),
+            ) => self.check_expr_path(qpath, expr, Some(args), call),
             _ => self.check_expr_kind(expr, expected),
         });
         let ty = self.resolve_vars_if_possible(ty);
@@ -289,7 +289,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             ExprKind::Path(QPath::LangItem(lang_item, _)) => {
                 self.check_lang_item_path(lang_item, expr)
             }
-            ExprKind::Path(ref qpath) => self.check_expr_path(qpath, expr, &[], None),
+            ExprKind::Path(ref qpath) => self.check_expr_path(qpath, expr, None, None),
             ExprKind::InlineAsm(asm) => {
                 // We defer some asm checks as we may not have resolved the input and output types yet (they may still be infer vars).
                 self.deferred_asm_checks.borrow_mut().push((asm, expr.hir_id));
@@ -501,7 +501,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         &self,
         qpath: &'tcx hir::QPath<'tcx>,
         expr: &'tcx hir::Expr<'tcx>,
-        args: &'tcx [hir::Expr<'tcx>],
+        args: Option<&'tcx [hir::Expr<'tcx>]>,
         call: Option<&'tcx hir::Expr<'tcx>>,
     ) -> Ty<'tcx> {
         let tcx = self.tcx;
@@ -563,7 +563,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     // We just want to check sizedness, so instead of introducing
                     // placeholder lifetimes with probing, we just replace higher lifetimes
                     // with fresh vars.
-                    let span = args.get(i).map(|a| a.span).unwrap_or(expr.span);
+                    let span = args.and_then(|args| args.get(i)).map_or(expr.span, |arg| arg.span);
                     let input = self.instantiate_binder_with_fresh_vars(
                         span,
                         infer::BoundRegionConversionTime::FnCall,