1 // RUN: %clang_cc1 -verify -std=c++1y %s
2 
3 namespace PR17846 {
4   template <typename T> constexpr T pi = T(3.14);
5   template <typename T> constexpr T tau = 2 * pi<T>;
6   constexpr double tau_double = tau<double>;
7   static_assert(tau_double == 6.28, "");
8 }
9 
10 namespace PR17848 {
11   template<typename T> constexpr T var = 12345;
f()12   template<typename T> constexpr T f() { return var<T>; }
13   constexpr int k = f<int>();
14   static_assert(k == 12345, "");
15 }
16 
17 namespace NonDependent {
18   template<typename T> constexpr T a = 0;
19   template<typename T> constexpr T b = a<int>;
20   static_assert(b<int> == 0, "");
21 }
22 
23 namespace InstantiationDependent {
24   int f(int);
25   void f(char);
26 
27   template<int> constexpr int a = 1;
28   template<typename T> constexpr T b = a<sizeof(sizeof(f(T())))>; // expected-error {{invalid application of 'sizeof' to an incomplete type 'void'}}
29 
30   static_assert(b<int> == 1, "");
31   static_assert(b<char> == 1, ""); // expected-note {{in instantiation of}} expected-error {{not an integral constant}}
32 
f()33   template<typename T> void f() {
34     static_assert(a<sizeof(sizeof(f(T())))> == 0, ""); // expected-error {{static_assert failed}}
35   }
36 }
37 
38 namespace PR24483 {
39   template<typename> struct A;
40   template<typename... T> A<T...> models;
41   template<> struct B models<>; // expected-error {{incomplete type 'struct B'}} expected-note {{forward declaration}}
42 }
43