[C++ Patch] PR 57599

[Paolo Carlini]

Hi,

this dynamic_cast bug, which just came in, notices that in the simple 
case of static conversion we forget to perform the cv-qualifier 
conversions. It seems to me that we are missing a build_nop.

I extended quite a bit the testcase, to references too, because at some 
point I got those wrong ;)

Tested x86_64-linux.

Thanks,
Paolo.

//////////////////////////


/cp
2013-06-13  Paolo Carlini  <paolo.carl...@oracle.com>

        PR c++/57599
        * rtti.c (build_dynamic_cast_1): In case of static conversion,
        remember to perform the cv-qualifier conversions.

/testsuite
2013-06-13  Paolo Carlini  <paolo.carl...@oracle.com>

        PR c++/57599
        * g++.dg/rtti/dyncast6.C: New.

Index: cp/rtti.c
===================================================================
--- cp/rtti.c   (revision 200041)
+++ cp/rtti.c   (working copy)
@@ -633,7 +633,8 @@ build_dynamic_cast_1 (tree type, tree expr, tsubst
                                binfo, 0, complain);
        if (TYPE_PTR_P (exprtype))
          expr = rvalue (expr);
-       return expr;
+       /* Add any qualifier conversions.  */
+       return build_nop (type, expr);
       }
   }
 
Index: testsuite/g++.dg/rtti/dyncast6.C
===================================================================
--- testsuite/g++.dg/rtti/dyncast6.C    (revision 0)
+++ testsuite/g++.dg/rtti/dyncast6.C    (working copy)
@@ -0,0 +1,59 @@
+// PR c++/57599
+
+class A { };
+
+class B : public A { };
+
+void p()
+{
+  B* b;
+
+  A* a1;
+  a1 = dynamic_cast<A*>(b);
+  a1 = dynamic_cast<const A*>(b);          // { dg-error "invalid" }
+  a1 = dynamic_cast<volatile A*>(b);       // { dg-error "invalid" }
+  a1 = dynamic_cast<const volatile A*>(b); // { dg-error "invalid" }
+
+  const A* a2;
+  a2 = dynamic_cast<A*>(b);
+  a2 = dynamic_cast<const A*>(b);
+  a2 = dynamic_cast<volatile A*>(b);       // { dg-error "invalid" }
+  a2 = dynamic_cast<const volatile A*>(b); // { dg-error "invalid" }
+
+  volatile A* a3;
+  a3 = dynamic_cast<A*>(b);
+  a3 = dynamic_cast<const A*>(b);          // { dg-error "invalid" }
+  a3 = dynamic_cast<volatile A*>(b);
+  a3 = dynamic_cast<const volatile A*>(b); // { dg-error "invalid" }
+
+  const volatile A* a4;
+  a4 = dynamic_cast<A*>(b);
+  a4 = dynamic_cast<const A*>(b);
+  a4 = dynamic_cast<volatile A*>(b);
+  a4 = dynamic_cast<const volatile A*>(b);
+}
+
+void r()
+{
+  B b;
+
+  A& a1 = dynamic_cast<A&>(b);
+  A& a2 = dynamic_cast<const A&>(b);                // { dg-error "invalid" }
+  A& a3 = dynamic_cast<volatile A&>(b);             // { dg-error "invalid" }
+  A& a4 = dynamic_cast<const volatile A&>(b);       // { dg-error "invalid" }
+
+  const A& ca1 = dynamic_cast<A&>(b);
+  const A& ca2 = dynamic_cast<const A&>(b);
+  const A& ca3 = dynamic_cast<volatile A&>(b);       // { dg-error "invalid" }
+  const A& ca4 = dynamic_cast<const volatile A&>(b); // { dg-error "invalid" }
+
+  volatile A& va1 = dynamic_cast<A&>(b);
+  volatile A& va2 = dynamic_cast<const A&>(b);       // { dg-error "invalid" }
+  volatile A& va3 = dynamic_cast<volatile A&>(b);
+  volatile A& va4 = dynamic_cast<const volatile A&>(b);// { dg-error "invalid" 
}
+
+  const volatile A& cva1 = dynamic_cast<A&>(b);
+  const volatile A& cva2 = dynamic_cast<const A&>(b);
+  const volatile A& cva3 = dynamic_cast<volatile A&>(b);
+  const volatile A& cva4 = dynamic_cast<const volatile A&>(b);
+}