re PR c++/67576 (expression of typeid( expression ) is evaluated twice)

	PR c++/67576

	PR c++/25466
	* rtti.c (build_typeid): Use save_expr, not stabilize_reference.

From-SVN: r231776

gcc/cp/ChangeLog

+2015-12-17  Jason Merrill  <jason@redhat.com>
+
+	PR c++/67576
+	PR c++/25466
+	* rtti.c (build_typeid): Use save_expr, not stabilize_reference.
+
 2015-12-16  Patrick Palka  <ppalka@gcc.gnu.org>
 
 	PR c++/16333

gcc/cp/rtti.c

@@ -332,7 +332,7 @@ build_typeid (tree exp, tsubst_flags_t complain)
       /* So we need to look into the vtable of the type of exp.
          Make sure it isn't a null lvalue.  */
       exp = cp_build_addr_expr (exp, complain);
-      exp = stabilize_reference (exp);
+      exp = save_expr (exp);
       cond = cp_convert (boolean_type_node, exp, complain);
       exp = cp_build_indirect_ref (exp, RO_NULL, complain);
     }

gcc/testsuite/g++.dg/rtti/typeid11.C

+// { dg-do run }
+
+#include <typeinfo>
+
+struct Base { virtual void foo() {} }; // polymorphic
+
+int main()
+{
+  Base b;
+  Base *ary[] = { &b, &b, &b};
+
+  int iter = 0;
+  typeid(*ary[iter++]);
+  if (iter != 1)	// should be 1
+    __builtin_abort();	// but 2
+}