diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index fc6a7898475d4fcdaa7fd12b7f4a895ad638f9a9..102f6e1464a6ebcbfec9da413ac9332de6108d50 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -8238,6 +8238,8 @@ struct uid_sensitive_constexpr_evaluation_checker
   bool evaluation_restricted_p () const;
 };
 
+void cp_tree_c_finish_parsing ();
+
 /* In cp-ubsan.c */
 extern void cp_ubsan_maybe_instrument_member_call (tree);
 extern void cp_ubsan_instrument_member_accesses (tree *);
diff --git a/gcc/cp/decl2.c b/gcc/cp/decl2.c
index af88e7f5cab420894e0005ccd44ccf768959f223..8769ff51be9ebbe009779ab24cf4189b4b25efbd 100644
--- a/gcc/cp/decl2.c
+++ b/gcc/cp/decl2.c
@@ -5257,6 +5257,7 @@ c_parse_final_cleanups (void)
   perform_deferred_noexcept_checks ();
 
   fini_constexpr ();
+  cp_tree_c_finish_parsing ();
   clear_consteval_vfns (consteval_vtables);
 
   /* The entire file is now complete.  If requested, dump everything
diff --git a/gcc/cp/tree.c b/gcc/cp/tree.c
index 0584a7b725e49e25097bf2b60706667011789884..e1ad0acb1f97210d153b16aac2e5e11799b6ee48 100644
--- a/gcc/cp/tree.c
+++ b/gcc/cp/tree.c
@@ -5926,6 +5926,15 @@ maybe_warn_zero_as_null_pointer_constant (tree expr, location_t loc)
   return false;
 }
 
+/* Release memory we no longer need after parsing.  */
+void
+cp_tree_c_finish_parsing ()
+{
+  if (previous_class_level)
+    invalidate_class_lookup_cache ();
+  deleted_copy_types = NULL;
+}
+
 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
 /* Complain that some language-specific thing hanging off a tree
    node has been accessed improperly.  */