re PR c++/80176 (cannot bind reference to static member function using object access expression)

	PR c++/80176
	* tree.c (lvalue_kind): For COMPONENT_REF with BASELINK second
	operand, if it is a static member function, recurse on the
	BASELINK.

	* g++.dg/init/ref23.C: New test.

From-SVN: r246825

gcc/cp/ChangeLog

+2017-04-10  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/80176
+	* tree.c (lvalue_kind): For COMPONENT_REF with BASELINK second
+	operand, if it is a static member function, recurse on the
+	BASELINK.
+
 2017-04-10  Marek Polacek  <polacek@redhat.com>
 
 	PR sanitizer/80348

gcc/cp/tree.c

@@ -105,6 +105,17 @@ lvalue_kind (const_tree ref)
       return op1_lvalue_kind;
 
     case COMPONENT_REF:
+      if (BASELINK_P (TREE_OPERAND (ref, 1)))
+	{
+	  tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (ref, 1));
+
+	  /* For static member function recurse on the BASELINK, we can get
+	     here e.g. from reference_binding.  If BASELINK_FUNCTIONS is
+	     OVERLOAD, the overload is resolved first if possible through
+	     resolve_address_of_overloaded_function.  */
+	  if (TREE_CODE (fn) == FUNCTION_DECL && DECL_STATIC_FUNCTION_P (fn))
+	    return lvalue_kind (TREE_OPERAND (ref, 1));
+	}
       op1_lvalue_kind = lvalue_kind (TREE_OPERAND (ref, 0));
       /* Look at the member designator.  */
       if (!op1_lvalue_kind)

gcc/testsuite/ChangeLog

+2017-04-10  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/80176
+	* g++.dg/init/ref23.C: New test.
+
 2017-04-10  Thomas Koenig  <tkoenig@gcc.gnu.org>
 
 	PR tree-optimization/80304

gcc/testsuite/g++.dg/init/ref23.C

+// PR c++/80176
+// { dg-do compile }
+
+struct X { static void foo(); static void baz(int); static int baz(double); } x;
+struct Y { void o(unsigned char); static void o(int); void o(double); } y;
+void X::foo() {}
+static void bar() {}
+void (&r1)() = x.foo;
+void (&r2)() = X::foo;
+void (&r3)() = bar;
+void (&r4)(int) = x.baz;
+int (&r5)(double) = x.baz;
+void (&r6)(int) = X::baz;
+int (&r7)(double) = X::baz;
+void (&r8)(int) = y.o;