1 // RUN: %clang_cc1 -verify -std=c++11 %s
2 
3 // Unlike in C++98, C++11 allows unions to have static data members.
4 
5 union U1 {
6   static constexpr int k1 = 0;
7   static const int k2 = k1;
8   static int k3 = k2; // expected-error {{non-const static data member must be initialized out of line}}
9   static constexpr double k4 = k2;
10   static const double k5 = k4; // expected-error {{requires 'constexpr' specifier}} expected-note {{add 'constexpr'}}
11   int n[k1 + 3];
12 };
13 
14 constexpr int U1::k1;
15 constexpr int U1::k2;
16 int U1::k3;
17 
18 const double U1::k4;
19 const double U1::k5;
20 
21 template<typename T>
22 union U2 {
23   static const int k1;
24   static double k2;
25   T t;
26 };
27 template<typename T> constexpr int U2<T>::k1 = sizeof(U2<T>);
28 template<typename T> double U2<T>::k2 = 5.3;
29 
30 static_assert(U2<int>::k1 == sizeof(int), "");
31 static_assert(U2<char>::k1 == sizeof(char), "");
32 
33 union U3 {
34   static const int k;
U3()35   U3() : k(0) {} // expected-error {{does not name a non-static data member}}
36 };
37 
38 struct S {
39   union {
40     static const int n; // expected-error {{static data member 'n' not allowed in anonymous union}}
41     int a;
42     int b;
43   };
44 };
45 static union {
46   static const int k; // expected-error {{static data member 'k' not allowed in anonymous union}}
47   int n;
48 };
49