xref: /llvm-project/clang/test/CXX/class/class.union/p2-0x.cpp (revision 7ae1b4a0ce9c7f269cf3069e41496a78e3f28d49)
142973755SRichard Smith // RUN: %clang_cc1 -verify -std=c++11 %s
242973755SRichard Smith 
342973755SRichard Smith // Unlike in C++98, C++11 allows unions to have static data members.
442973755SRichard Smith 
542973755SRichard Smith union U1 {
642973755SRichard Smith   static constexpr int k1 = 0;
742973755SRichard Smith   static const int k2 = k1;
842973755SRichard Smith   static int k3 = k2; // expected-error {{non-const static data member must be initialized out of line}}
942973755SRichard Smith   static constexpr double k4 = k2;
108505c295SDavid Blaikie   static const double k5 = k4; // expected-error {{requires 'constexpr' specifier}} expected-note {{add 'constexpr'}}
1142973755SRichard Smith   int n[k1 + 3];
1242973755SRichard Smith };
1342973755SRichard Smith 
1442973755SRichard Smith constexpr int U1::k1;
1542973755SRichard Smith constexpr int U1::k2;
1642973755SRichard Smith int U1::k3;
1742973755SRichard Smith 
1842973755SRichard Smith const double U1::k4;
1942973755SRichard Smith const double U1::k5;
2042973755SRichard Smith 
2142973755SRichard Smith template<typename T>
2242973755SRichard Smith union U2 {
2342973755SRichard Smith   static const int k1;
2442973755SRichard Smith   static double k2;
2542973755SRichard Smith   T t;
2642973755SRichard Smith };
2742973755SRichard Smith template<typename T> constexpr int U2<T>::k1 = sizeof(U2<T>);
2842973755SRichard Smith template<typename T> double U2<T>::k2 = 5.3;
2942973755SRichard Smith 
3042973755SRichard Smith static_assert(U2<int>::k1 == sizeof(int), "");
3142973755SRichard Smith static_assert(U2<char>::k1 == sizeof(char), "");
3242973755SRichard Smith 
3342973755SRichard Smith union U3 {
3442973755SRichard Smith   static const int k;
U3()3542973755SRichard Smith   U3() : k(0) {} // expected-error {{does not name a non-static data member}}
3642973755SRichard Smith };
374fa6aec9SRichard Smith 
384fa6aec9SRichard Smith struct S {
394fa6aec9SRichard Smith   union {
40*7ae1b4a0SRichard Smith     static const int n; // expected-error {{static data member 'n' not allowed in anonymous union}}
414fa6aec9SRichard Smith     int a;
424fa6aec9SRichard Smith     int b;
434fa6aec9SRichard Smith   };
444fa6aec9SRichard Smith };
454fa6aec9SRichard Smith static union {
46*7ae1b4a0SRichard Smith   static const int k; // expected-error {{static data member 'k' not allowed in anonymous union}}
474fa6aec9SRichard Smith   int n;
484fa6aec9SRichard Smith };
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