gcc/testsuite/g++.dg/cpp0x/decltype3.C

   1 // { dg-do compile { target c++11 } }
   2
   3 template<typename T, typename U>
   4 struct is_same
   5 {
   6   static const bool value = false;
   7 };
   8
   9 template<typename T>
  10 struct is_same<T, T>
  11 {
  12   static const bool value = true;
  13 };
  14
  15 #define CHECK_DECLTYPE(DECLTYPE,RESULT) \
  16   static_assert(is_same< DECLTYPE , RESULT >::value, #DECLTYPE " should be " #RESULT)
  17
  18 class A {
  19 public:
  20   int a;
  21   int& b;
  22   static int c;
  23
  24   A(int& b) : b(b) { }
  25
  26   void foo() {
  27     CHECK_DECLTYPE(decltype(a), int);
  28     CHECK_DECLTYPE(decltype(this->a), int);
  29     CHECK_DECLTYPE(decltype((*this).a), int);
  30     CHECK_DECLTYPE(decltype(b), int&);
  31     CHECK_DECLTYPE(decltype(c), int);
  32   }
  33   void bar() const {
  34     CHECK_DECLTYPE(decltype(a), int);
  35     CHECK_DECLTYPE(decltype(b), int&);
  36     CHECK_DECLTYPE(decltype(c), int);
  37   }
  38 };
  39
  40 int b;
  41 A aa(b);
  42 const A& caa = aa;
  43 CHECK_DECLTYPE(decltype(aa.a), int);
  44 CHECK_DECLTYPE(decltype(aa.b), int&);
  45 CHECK_DECLTYPE(decltype(caa.a), int);
  46
  47 class B {
  48 public:
  49   int a;
  50   enum B_enum { b };
  51   decltype(a) c;
  52   decltype(a) foo() { return 0; }
  53   decltype(b) enums_are_in_scope() { return b; } // ok
  54 };
  55
  56 CHECK_DECLTYPE(decltype(aa.*&A::a), int&);
  57 decltype(aa.*&A::b) zz; // { dg-error "18:cannot create pointer to reference member" "cannot" }
  58
  59 CHECK_DECLTYPE(decltype(caa.*&A::a), const int&);
  60
  61 class X {
  62   void foo() {
  63     CHECK_DECLTYPE(decltype(this), X*);
  64     CHECK_DECLTYPE(decltype(*this), X&);
  65   }
  66   void bar() const {
  67     CHECK_DECLTYPE(decltype(this), const X*);
  68     CHECK_DECLTYPE(decltype(*this), const X&);
  69   }
  70 };
  71