clang/test/SemaCXX/dynamic-cast.cpp

   1 // RUN: %clang_cc1 -fsyntax-only -verify %s
   2
   3 struct A {};
   4 struct B : A {};
   5 struct C : B {};
   6
   7 struct D : private A {};
   8 struct E : A {};
   9 struct F : B, E {};
  10
  11 struct Incomplete; // expected-note 2 {{forward declaration of 'Incomplete'}}
  12
  13 struct Poly
  14 {
  15   virtual void f();
  16 };
  17
  18 struct PolyDerived : Poly
  19 {
  20 };
  21
  22 void basic_bad()
  23 {
  24   // ptr -> nonptr
  25   (void)dynamic_cast<A>((A*)0); // expected-error {{invalid target type 'A' for dynamic_cast; target type must be a reference or pointer type to a defined class}}
  26   // nonptr -> ptr
  27   (void)dynamic_cast<A*>(0); // expected-error {{cannot use dynamic_cast to convert from 'int' to 'A *'}}
  28   // ptr -> noncls
  29   (void)dynamic_cast<int*>((A*)0); // expected-error {{'int' is not a class type}}
  30   // noncls -> ptr
  31   (void)dynamic_cast<A*>((int*)0); // expected-error {{'int' is not a class type}}
  32   // ref -> noncls
  33   (void)dynamic_cast<int&>(*((A*)0)); // expected-error {{'int' is not a class type}}
  34   // noncls -> ref
  35   (void)dynamic_cast<A&>(*((int*)0)); // expected-error {{'int' is not a class type}}
  36   // ptr -> incomplete
  37   (void)dynamic_cast<Incomplete*>((A*)0); // expected-error {{'Incomplete' is an incomplete type}}
  38   // incomplete -> ptr
  39   (void)dynamic_cast<A*>((Incomplete*)0); // expected-error {{'Incomplete' is an incomplete type}}
  40   // rvalue -> lvalue
  41   (void)dynamic_cast<A&>(A()); // expected-error {{dynamic_cast from rvalue to reference type 'A &'}}
  42 }
  43
  44 void same()
  45 {
  46   (void)dynamic_cast<A*>((A*)0);
  47   (void)dynamic_cast<A&>(*((A*)0));
  48 }
  49
  50 void up()
  51 {
  52   (void)dynamic_cast<A*>((B*)0);
  53   (void)dynamic_cast<A&>(*((B*)0));
  54   (void)dynamic_cast<A*>((C*)0);
  55   (void)dynamic_cast<A&>(*((C*)0));
  56
  57   // Inaccessible
  58   //(void)dynamic_cast<A*>((D*)0);
  59   //(void)dynamic_cast<A&>(*((D*)0));
  60
  61   // Ambiguous
  62   (void)dynamic_cast<A*>((F*)0); // expected-error {{ambiguous conversion from derived class 'F' to base class 'A':\n    struct F -> B -> A\n    struct F -> E -> A}}
  63   (void)dynamic_cast<A&>(*((F*)0)); // expected-error {{ambiguous conversion from derived class 'F' to base class 'A':\n    struct F -> B -> A\n    struct F -> E -> A}}
  64 }
  65
  66 void poly()
  67 {
  68   (void)dynamic_cast<A*>((Poly*)0);
  69   (void)dynamic_cast<A&>(*((Poly*)0));
  70   (void)dynamic_cast<A*>((PolyDerived*)0);
  71   (void)dynamic_cast<A&>(*((PolyDerived*)0));
  72
  73   // Not polymorphic source
  74   (void)dynamic_cast<Poly*>((A*)0); // expected-error {{'A' is not polymorphic}}
  75   (void)dynamic_cast<PolyDerived&>(*((A*)0)); // expected-error {{'A' is not polymorphic}}
  76 }