[gcc r13-1018] c++: non-templated friends [PR105852]

[gcc r13-1018] c++: non-templated friends [PR105852]

[Jason Merrill]

https://gcc.gnu.org/g:e8ed26c2ac38ab1f6ed5a627d9089a9243e06a0c

commit r13-1018-ge8ed26c2ac38ab1f6ed5a627d9089a9243e06a0c
Author: Jason Merrill <jason@redhat.com>
Date:   Tue Jun 7 15:52:30 2022 -0400

    c++: non-templated friends [PR105852]
    
    The previous patch for 105852 avoids copying DECL_TEMPLATE_INFO from a
    non-templated friend, but it really shouldn't have it in the first place.
    
            PR c++/105852
    
    gcc/cp/ChangeLog:
    
            * decl.cc (duplicate_decls): Change non-templated friend
            check to an assert.
            * pt.cc (tsubst_function_decl): Don't set DECL_TEMPLATE_INFO
            on non-templated friends.
            (tsubst_friend_function): Adjust.

Diff:
---
 gcc/cp/decl.cc |  9 +++++----
 gcc/cp/pt.cc   | 14 ++++++++++----
 2 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
index 3e869954ccb..7f3b3c3c588 100644
--- a/gcc/cp/decl.cc
+++ b/gcc/cp/decl.cc
@@ -2664,10 +2664,11 @@ duplicate_decls (tree newdecl, tree olddecl, bool hiding, bool was_hidden)
 		  = TINFO_USED_TEMPLATE_ID (new_template_info);
 	    }
 
-	  if (non_templated_friend_p (olddecl))
-	    /* Don't copy tinfo from a non-templated friend (PR105761).  */;
-	  else
-	    DECL_TEMPLATE_INFO (newdecl) = DECL_TEMPLATE_INFO (olddecl);
+	  /* We don't want to copy template info from a non-templated friend
+	     (PR105761), but these shouldn't have DECL_TEMPLATE_INFO now.  */
+	  gcc_checking_assert (!DECL_TEMPLATE_INFO (olddecl)
+			       || !non_templated_friend_p (olddecl));
+	  DECL_TEMPLATE_INFO (newdecl) = DECL_TEMPLATE_INFO (olddecl);
 	}
 
       if (DECL_DECLARES_FUNCTION_P (newdecl))
diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
index 9c1b026857e..3154186ac20 100644
--- a/gcc/cp/pt.cc
+++ b/gcc/cp/pt.cc
@@ -11298,9 +11298,10 @@ tsubst_friend_function (tree decl, tree args)
       tree new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
       tree new_friend_result_template_info = NULL_TREE;
       bool new_friend_is_defn =
-	(DECL_INITIAL (DECL_TEMPLATE_RESULT
-		       (template_for_substitution (new_friend)))
-	 != NULL_TREE);
+	(new_friend_template_info
+	 && (DECL_INITIAL (DECL_TEMPLATE_RESULT
+			   (template_for_substitution (new_friend)))
+	     != NULL_TREE));
       tree not_tmpl = new_friend;
 
       if (TREE_CODE (new_friend) == TEMPLATE_DECL)
@@ -14084,6 +14085,10 @@ tsubst_function_decl (tree t, tree args, tsubst_flags_t complain,
 	  && !LAMBDA_FUNCTION_P (t))
 	return t;
 
+      /* A non-templated friend doesn't get DECL_TEMPLATE_INFO.  */
+      if (non_templated_friend_p (t))
+	goto friend_case;
+
       /* Calculate the most general template of which R is a
 	 specialization.  */
       gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
@@ -14129,6 +14134,7 @@ tsubst_function_decl (tree t, tree args, tsubst_flags_t complain,
 	 tsubst_friend_function, and we want only to create a
 	 new decl (R) with appropriate types so that we can call
 	 determine_specialization.  */
+    friend_case:
       gen_tmpl = NULL_TREE;
       argvec = NULL_TREE;
     }
@@ -14324,7 +14330,7 @@ tsubst_function_decl (tree t, tree args, tsubst_flags_t complain,
       /* If this is an instantiation of a member template, clone it.
 	 If it isn't, that'll be handled by
 	 clone_constructors_and_destructors.  */
-      if (PRIMARY_TEMPLATE_P (gen_tmpl))
+      if (gen_tmpl && PRIMARY_TEMPLATE_P (gen_tmpl))
 	clone_cdtor (r, /*update_methods=*/false);
     }
   else if ((complain & tf_error) != 0