From: Patrick Palka <ppalka@redhat.com>
Date: Wed, 6 Mar 2024 01:36:36 +0000 (-0500)
Subject: c++/modules: befriending template from current class scope
X-Git-Tag: basepoints/gcc-15~812
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b0d11bb02a4a4c7d61e9b53411ccdc54610b1429;p=thirdparty%2Fgcc.git

c++/modules: befriending template from current class scope

Here the TEMPLATE_DECL representing the template friend declaration
naming B has class scope since the template B has class scope, but
get_merge_kind assumes all DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P
TEMPLATE_DECL have namespace scope and wrongly returns MK_named instead
of MK_local_friend for the friend.

gcc/cp/ChangeLog:

	* module.cc (trees_out::get_merge_kind) <case depset::EK_DECL>:
	Accomodate class-scope DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P
	TEMPLATE_DECL.  Consolidate IDENTIFIER_ANON_P cases.

gcc/testsuite/ChangeLog:

	* g++.dg/modules/friend-7.h: New test.
	* g++.dg/modules/friend-7_a.H: New test.
	* g++.dg/modules/friend-7_b.C: New test.

Reviewed-by: Jason Merrill <jason@redhat.com>
---

diff --git a/gcc/cp/module.cc b/gcc/cp/module.cc
index 67f132d28d7a..80b63a70a62c 100644
--- a/gcc/cp/module.cc
+++ b/gcc/cp/module.cc
@@ -10498,21 +10498,20 @@ trees_out::get_merge_kind (tree decl, depset *dep)
 		    }
 		}
 
-	    if (RECORD_OR_UNION_TYPE_P (ctx))
+	    if (TREE_CODE (decl) == TEMPLATE_DECL
+		&& DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P (decl))
 	      {
-		if (IDENTIFIER_ANON_P (DECL_NAME (decl)))
-		  mk = MK_field;
+		mk = MK_local_friend;
 		break;
 	      }
 
-	    if (TREE_CODE (decl) == TEMPLATE_DECL
-		&& DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P (decl))
-	      mk = MK_local_friend;
-	    else if (IDENTIFIER_ANON_P (DECL_NAME (decl)))
+	    if (IDENTIFIER_ANON_P (DECL_NAME (decl)))
 	      {
-		if (DECL_IMPLICIT_TYPEDEF_P (decl)
-		    && UNSCOPED_ENUM_P (TREE_TYPE (decl))
-		    && TYPE_VALUES (TREE_TYPE (decl)))
+		if (RECORD_OR_UNION_TYPE_P (ctx))
+		  mk = MK_field;
+		else if (DECL_IMPLICIT_TYPEDEF_P (decl)
+			 && UNSCOPED_ENUM_P (TREE_TYPE (decl))
+			 && TYPE_VALUES (TREE_TYPE (decl)))
 		  /* Keyed by first enum value, and underlying type.  */
 		  mk = MK_enum;
 		else
diff --git a/gcc/testsuite/g++.dg/modules/friend-7.h b/gcc/testsuite/g++.dg/modules/friend-7.h
new file mode 100644
index 000000000000..c0f00394f3bb
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/friend-7.h
@@ -0,0 +1,5 @@
+template<class T>
+struct A {
+  template<class U> struct B { };
+  template<class U> friend struct B;
+};
diff --git a/gcc/testsuite/g++.dg/modules/friend-7_a.H b/gcc/testsuite/g++.dg/modules/friend-7_a.H
new file mode 100644
index 000000000000..e750e4c7d8d8
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/friend-7_a.H
@@ -0,0 +1,3 @@
+// { dg-additional-options "-fmodule-header" }
+// { dg-module-cmi {} }
+#include "friend-7.h"
diff --git a/gcc/testsuite/g++.dg/modules/friend-7_b.C b/gcc/testsuite/g++.dg/modules/friend-7_b.C
new file mode 100644
index 000000000000..eb5e45a3f431
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/friend-7_b.C
@@ -0,0 +1,6 @@
+// { dg-additional-options "-fmodules-ts" }
+#include "friend-7.h"
+import "friend-7_a.H";
+
+A<int> a;
+A<int>::B<char> b;