re PR c++/71979 (ICE with on C++ code with incorrect type in overloaded base…

re PR c++/71979 (ICE with on C++ code with incorrect type in overloaded base class '=' operator: in build_base_path, at cp/class.c:304)

/cp
2016-09-22  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/71979
	* class.c (build_base_path): Allow for lookup_base returning
	NULL_TREE.

/testsuite
2016-09-22  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/71979
	* g++.dg/cpp0x/pr71979.C: New.

From-SVN: r240373

gcc/cp/ChangeLog

+2016-09-22  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/71979
+	* class.c (build_base_path): Allow for lookup_base returning
+	NULL_TREE.
+
 2016-09-21  Jason Merrill  <jason@redhat.com>
 
 	Core 903

gcc/cp/class.c

@@ -296,12 +296,13 @@ build_base_path (enum tree_code code,
       /* This can happen when adjust_result_of_qualified_name_lookup can't
 	 find a unique base binfo in a call to a member function.  We
 	 couldn't give the diagnostic then since we might have been calling
-	 a static member function, so we do it now.  */
+	 a static member function, so we do it now.  In other cases, eg.
+	 during error recovery (c++/71979), we may not have a base at all.  */
       if (complain & tf_error)
 	{
 	  tree base = lookup_base (probe, BINFO_TYPE (d_binfo),
 				   ba_unique, NULL, complain);
-	  gcc_assert (base == error_mark_node);
+	  gcc_assert (base == error_mark_node || !base);
 	}
       return error_mark_node;
     }

gcc/testsuite/ChangeLog

+2016-09-22  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/71979
+	* g++.dg/cpp0x/pr71979.C: New.
+
 2016-09-22  Bernd Edlinger  <bernd.edlinger@hotmail.de>
 
 	* g++.dg/pr77550.C: Use __SIZE_TYPE__.

gcc/testsuite/g++.dg/cpp0x/pr71979.C

+// PR c++/71979
+// { dg-do compile { target c++11 } }
+
+struct A
+{ 
+  A & operator= (A &);
+};
+
+struct B : A {};   // { dg-error "cannot bind" }
+
+void foo ()
+{ 
+  B b;
+  b = B ();  // { dg-error "use of deleted" }
+}