fix #64430

Author: 12101111

src/librustc/ty/context.rs

@@ -2396,9 +2396,9 @@ impl<'tcx> TyCtxt<'tcx> {
     }
 
     #[inline]
-    pub fn mk_lang_item(self, ty: Ty<'tcx>, item: lang_items::LangItem)  -> Ty<'tcx> {
-        let def_id = self.require_lang_item(item, None);
-        self.mk_generic_adt(def_id, ty)
+    pub fn mk_lang_item(self, ty: Ty<'tcx>, item: lang_items::LangItem)  -> Option<Ty<'tcx>> {
+        let def_id = self.lang_items().require(item).ok()?;
+        Some(self.mk_generic_adt(def_id, ty))
     }
 
     #[inline]

src/librustc_typeck/check/expr.rs

@@ -813,18 +813,20 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         error: MethodError<'tcx>
     ) {
         let rcvr = &args[0];
-        let try_alt_rcvr = |err: &mut DiagnosticBuilder<'_>, new_rcvr_t| {
-            if let Ok(pick) = self.lookup_probe(
-                span,
-                segment.ident,
-                new_rcvr_t,
-                rcvr,
-                probe::ProbeScope::AllTraits,
-            ) {
-                err.span_label(
-                    pick.item.ident.span,
-                    &format!("the method is available for `{}` here", new_rcvr_t),
-                );
+        let try_alt_rcvr = |err: &mut DiagnosticBuilder<'_>, rcvr_t, lang_item| {
+            if let Some(new_rcvr_t) = self.tcx.mk_lang_item(rcvr_t, lang_item) {
+                if let Ok(pick) = self.lookup_probe(
+                    span,
+                    segment.ident,
+                    new_rcvr_t,
+                    rcvr,
+                    probe::ProbeScope::AllTraits,
+                ) {
+                    err.span_label(
+                        pick.item.ident.span,
+                        &format!("the method is available for `{}` here", new_rcvr_t),
+                    );
+                }
             }
         };
 
@@ -840,17 +842,10 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 // Try alternative arbitrary self types that could fulfill this call.
                 // FIXME: probe for all types that *could* be arbitrary self-types, not
                 // just this whitelist.
-                let box_rcvr_t = self.tcx.mk_box(rcvr_t);
-                try_alt_rcvr(&mut err, box_rcvr_t);
-                let pin_rcvr_t = self.tcx.mk_lang_item(
-                    rcvr_t,
-                    lang_items::PinTypeLangItem,
-                );
-                try_alt_rcvr(&mut err, pin_rcvr_t);
-                let arc_rcvr_t = self.tcx.mk_lang_item(rcvr_t, lang_items::Arc);
-                try_alt_rcvr(&mut err, arc_rcvr_t);
-                let rc_rcvr_t = self.tcx.mk_lang_item(rcvr_t, lang_items::Rc);
-                try_alt_rcvr(&mut err, rc_rcvr_t);
+                try_alt_rcvr(&mut err, rcvr_t, lang_items::OwnedBoxLangItem);
+                try_alt_rcvr(&mut err, rcvr_t, lang_items::PinTypeLangItem);
+                try_alt_rcvr(&mut err, rcvr_t, lang_items::Arc);
+                try_alt_rcvr(&mut err, rcvr_t, lang_items::Rc);
             }
             err.emit();
         }