re PR c++/58714 (Bogus overload resolution for the assignment operator in…

re PR c++/58714 (Bogus overload resolution for the assignment operator in assignment to a conditional)

	PR c++/58714
	* tree.c (stabilize_expr): A stabilized prvalue is an xvalue.

From-SVN: r210283

gcc/cp/ChangeLog

 2014-05-09  Jason Merrill  <jason@redhat.com>
 
+	PR c++/58714
+	* tree.c (stabilize_expr): A stabilized prvalue is an xvalue.
+
 	PR c++/54348
 	* call.c (build_conditional_expr_1): If overload resolution finds
 	no match, just say "different types".

gcc/cp/tree.c

@@ -3785,6 +3785,10 @@ stabilize_expr (tree exp, tree* initp)
     {
       init_expr = get_target_expr (exp);
       exp = TARGET_EXPR_SLOT (init_expr);
+      if (CLASS_TYPE_P (TREE_TYPE (exp)))
+	exp = move (exp);
+      else
+	exp = rvalue (exp);
     }
   else
     {

gcc/testsuite/g++.dg/cpp0x/rv-cond1.C

+// PR c++/58714
+// { dg-do compile { target c++11 } }
+
+struct X {
+  X& operator=(const X&) = delete;
+  X& operator=(X&& ) = default;
+};
+
+void f(bool t) {
+  X a, b;
+  *(t ? &a : &b) = X();
+  (t ? a : b) = X();
+}

gcc/testsuite/g++.dg/expr/cond12.C

+// PR c++/58714
+// { dg-do run }
+
+struct X {
+    X& operator=(const X&){}
+    X& operator=(X&){__builtin_abort();}
+};
+
+int main(int argv,char**) {
+  X a, b;
+  ((argv > 2) ? a : b) = X();
+}