re PR c++/45282 (wrong decltype result for .*)

	PR c++/45282
	* typeck2.c (build_m_component_ref): Handle prvalue object.

From-SVN: r197130

gcc/cp/ChangeLog

+2013-03-26  Jason Merrill  <jason@redhat.com>
+
+	PR c++/45282
+	* typeck2.c (build_m_component_ref): Handle prvalue object.
+
 2013-03-26  Gabriel Dos Reis  <gdr@integrable-solutions.net>
 
 	* cp-gimplify.c (cp_genericize_r): Use VAR_OR_FUNCTION_DECL_P.

gcc/cp/typeck2.c

@@ -1671,7 +1671,7 @@ build_m_component_ref (tree datum, tree component, tsubst_flags_t complain)
 
   if (TYPE_PTRDATAMEM_P (ptrmem_type))
     {
-      bool is_lval = real_lvalue_p (datum);
+      cp_lvalue_kind kind = lvalue_kind (datum);
       tree ptype;
 
       /* Compute the type of the field, as described in [expr.ref].
@@ -1701,7 +1701,9 @@ build_m_component_ref (tree datum, tree component, tsubst_flags_t complain)
 	return error_mark_node;
 
       /* If the object expression was an rvalue, return an rvalue.  */
-      if (!is_lval)
+      if (kind & clk_class)
+	datum = rvalue (datum);
+      else if (kind & clk_rvalueref)
 	datum = move (datum);
       return datum;
     }

gcc/testsuite/g++.dg/cpp0x/decltype49.C

+// PR c++/45282
+// { dg-require-effective-target c++11 }
+
+struct A { int i; };
+int A::*ipm = &A::i;
+
+template <class T, class U> class assert_same_type;
+template <class T> class assert_same_type<T,T> { };
+
+assert_same_type<decltype(A().*ipm),int> x2;