re PR c++/70209 (ICE in strip_typedefs, at cp/tree.c:1377)

	PR c++/70209
	* tree.c (strip_typedefs): Call strip_typedefs again on the
	DECL_ORIGINAL_TYPE result.

	* g++.dg/ext/attribute-may-alias-4.C: New test.

From-SVN: r234234

gcc/cp/ChangeLog

+2016-03-15  Marek Polacek  <polacek@redhat.com>
+
+	PR c++/70209
+	* tree.c (strip_typedefs): Call strip_typedefs again on the
+	DECL_ORIGINAL_TYPE result.
+
 2016-03-15  Jason Merrill  <jason@redhat.com>
 
 	PR c++/70095

gcc/cp/tree.c

@@ -1460,9 +1460,12 @@ strip_typedefs (tree t, bool *remove_attributes)
   if (!result)
     {
       if (typedef_variant_p (t))
-	/* Explicitly get the underlying type, as TYPE_MAIN_VARIANT doesn't
-	   strip typedefs with attributes.  */
-	result = TYPE_MAIN_VARIANT (DECL_ORIGINAL_TYPE (TYPE_NAME (t)));
+	{
+	  /* Explicitly get the underlying type, as TYPE_MAIN_VARIANT doesn't
+	     strip typedefs with attributes.  */
+	  result = TYPE_MAIN_VARIANT (DECL_ORIGINAL_TYPE (TYPE_NAME (t)));
+	  result = strip_typedefs (result);
+	}
       else
 	result = TYPE_MAIN_VARIANT (t);
     }

gcc/testsuite/ChangeLog

+2016-03-15  Marek Polacek  <polacek@redhat.com>
+
+	PR c++/70209
+	* g++.dg/ext/attribute-may-alias-4.C: New test.
+
 2016-03-15  Alexander Monakov  <amonakov@ispras.ru>
 
 	* g++.dg/pr63384.C: Add -w to dg-options.  Remove '-toggle' in

gcc/testsuite/g++.dg/ext/attribute-may-alias-4.C

+// PR c++/70209
+
+struct V {
+  typedef float F;
+  template <typename S> void m_fn1(S);
+};
+
+template <typename> struct A {
+  typedef V::F Ta __attribute__((__may_alias__));
+  Ta *m_data;
+  void m_fn2(V &);
+};
+
+template <>
+void A<int>::m_fn2(V &p) {
+  p.m_fn1(m_data);
+}