From 080384d6057018108dd588b456ed53ec0b752769 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Mon, 27 Feb 2017 15:17:17 -0500
Subject: [PATCH] PR c++/71568 - SFINAE forming pointer to member function

	* init.c (build_offset_ref): Check the return value of
	perform_or_defer_access_check.

From-SVN: r245763
---
 gcc/cp/ChangeLog                      |  6 ++++++
 gcc/cp/init.c                         | 25 +++++++++++++++----------
 gcc/testsuite/g++.dg/cpp0x/sfinae58.C | 12 ++++++++++++
 3 files changed, 33 insertions(+), 10 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp0x/sfinae58.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 03f92565772..5792e5d08d0 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2017-02-27  Jason Merrill  <jason@redhat.com>
+
+	PR c++/71568 - SFINAE forming pointer to member function
+	* init.c (build_offset_ref): Check the return value of
+	perform_or_defer_access_check.
+
 2017-02-27  Marek Polacek  <polacek@redhat.com>
 
 	* decl.c (expand_static_init): Add missing } in a comment.
diff --git a/gcc/cp/init.c b/gcc/cp/init.c
index b8308227988..99eeb8a893f 100644
--- a/gcc/cp/init.c
+++ b/gcc/cp/init.c
@@ -2043,14 +2043,16 @@ build_offset_ref (tree type, tree member, bool address_p,
 	       If the access is to form a pointer to member, the
 	       nested-name-specifier shall name the derived class
 	       (or any class derived from that class).  */
+	  bool ok;
 	  if (address_p && DECL_P (t)
 	      && DECL_NONSTATIC_MEMBER_P (t))
-	    perform_or_defer_access_check (TYPE_BINFO (type), t, t,
-					   complain);
+	    ok = perform_or_defer_access_check (TYPE_BINFO (type), t, t,
+						complain);
 	  else
-	    perform_or_defer_access_check (basebinfo, t, t,
-					   complain);
-
+	    ok = perform_or_defer_access_check (basebinfo, t, t,
+						complain);
+	  if (!ok)
+	    return error_mark_node;
 	  if (DECL_STATIC_FUNCTION_P (t))
 	    return t;
 	  member = t;
@@ -2059,11 +2061,14 @@ build_offset_ref (tree type, tree member, bool address_p,
 	TREE_TYPE (member) = unknown_type_node;
     }
   else if (address_p && TREE_CODE (member) == FIELD_DECL)
-    /* We need additional test besides the one in
-       check_accessibility_of_qualified_id in case it is
-       a pointer to non-static member.  */
-    perform_or_defer_access_check (TYPE_BINFO (type), member, member,
-				   complain);
+    {
+      /* We need additional test besides the one in
+	 check_accessibility_of_qualified_id in case it is
+	 a pointer to non-static member.  */
+      if (!perform_or_defer_access_check (TYPE_BINFO (type), member, member,
+					  complain))
+	return error_mark_node;
+    }
 
   if (!address_p)
     {
diff --git a/gcc/testsuite/g++.dg/cpp0x/sfinae58.C b/gcc/testsuite/g++.dg/cpp0x/sfinae58.C
new file mode 100644
index 00000000000..aaa38d3ed06
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/sfinae58.C
@@ -0,0 +1,12 @@
+// PR c++/71568
+// { dg-do compile { target c++11 } }
+
+template <typename T> class F : T {};
+template <typename> using void_t = void;
+template <class, class = void> struct G;
+template <typename T> struct G<T, void_t<decltype(&T::nlog_custom)>> {};
+struct D {
+  void nlog_custom();
+};
+G<F<D>> g;			// { dg-error "incomplete" }
+
-- 
2.30.2