re PR c++/49085 (Crash with SIGSEGV during compilation.)

	PR c++/49085
	* semantics.c (finish_offsetof): Complain about incomplete type.

From-SVN: r175758

gcc/cp/ChangeLog

+2011-07-01  Jason Merrill  <jason@redhat.com>
+
+	PR c++/49085
+	* semantics.c (finish_offsetof): Complain about incomplete type.
+
 2011-06-30  Jason Merrill  <jason@redhat.com>
 
 	PR c++/49387

gcc/cp/semantics.c

@@ -3422,6 +3422,12 @@ finish_offsetof (tree expr)
     }
   if (REFERENCE_REF_P (expr))
     expr = TREE_OPERAND (expr, 0);
+  if (TREE_CODE (expr) == COMPONENT_REF)
+    {
+      tree object = TREE_OPERAND (expr, 0);
+      if (!complete_type_or_else (TREE_TYPE (object), object))
+	return error_mark_node;
+    }
   return fold_offsetof (expr, NULL_TREE);
 }
 

gcc/testsuite/ChangeLog

+2011-07-01  Jason Merrill  <jason@redhat.com>
+
+	PR c++/49085
+	* g++.dg/template/offsetof2.C: New.
+
 2011-07-01  Kai Tietz  <ktietz@redhat.com>
 
         * gcc.dg/tree-ssa/bitwise-sink.c: New test.

gcc/testsuite/g++.dg/template/offsetof2.C

+// PR c++/49085
+
+template <class T>
+struct A			// { dg-error "declaration" }
+{
+  int i, j;
+  int ar[__builtin_offsetof(A,j)]; // { dg-error "incomplete type" }
+};
+
+A<int> a;