===================================================================
@@ -1366,7 +1366,7 @@ synthesized_method_walk (tree ctype, special_funct
}
vbases = CLASSTYPE_VBASECLASSES (ctype);
- if (vec_safe_is_empty (vbases))
+ if (vbases == NULL)
/* No virtual bases to worry about. */;
else if (!assign_p)
{
@@ -1656,10 +1656,12 @@ implicitly_declare_fn (special_function_kind kind,
/* Don't bother marking a deleted constructor as constexpr. */
if (deleted_p)
constexpr_p = false;
- /* A trivial copy/move constructor is also a constexpr constructor. */
+ /* A trivial copy/move constructor is also a constexpr constructor,
+ unless the class has virtual bases (7.1.5p4). */
else if (trivial_p && cxx_dialect >= cxx11
&& (kind == sfk_copy_constructor
- || kind == sfk_move_constructor))
+ || kind == sfk_move_constructor)
+ && !CLASSTYPE_VBASECLASSES (type))
gcc_assert (constexpr_p);
if (!trivial_p && type_has_trivial_fn (type, kind))
===================================================================
@@ -0,0 +1,14 @@
+// PR c++/60047
+// { dg-do compile { target c++11 } }
+
+struct B { };
+
+template<typename T> struct A : virtual B
+{
+ A();
+ A(const A&);
+};
+
+template<typename T> A<T>::A(const A<T>&) = default;
+
+A<int> a = A<int>();