78 lines
1.9 KiB
C++
78 lines
1.9 KiB
C++
// RUN: %clang_cc1 -std=c++11 -verify %s
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namespace UseBeforeDefinition {
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struct A {
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template<typename T> static constexpr T get() { return T(); }
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// ok, not a constant expression.
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int n = get<int>();
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};
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// ok, constant expression.
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constexpr int j = A::get<int>();
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template<typename T> constexpr int consume(T);
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// ok, not a constant expression.
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const int k = consume(0); // expected-note {{here}}
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template<typename T> constexpr int consume(T) { return 0; }
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// ok, constant expression.
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constexpr int l = consume(0);
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constexpr int m = k; // expected-error {{constant expression}} expected-note {{initializer of 'k'}}
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}
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namespace IntegralConst {
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template<typename T> constexpr T f(T n) { return n; }
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enum E {
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v = f(0), w = f(1) // ok
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};
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static_assert(w == 1, "");
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char arr[f('x')]; // ok
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static_assert(sizeof(arr) == 'x', "");
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}
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namespace ConvertedConst {
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template<typename T> constexpr T f(T n) { return n; }
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int f() {
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switch (f()) {
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case f(4): return 0;
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}
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return 1;
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}
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}
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namespace OverloadResolution {
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template<typename T> constexpr T f(T t) { return t; }
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template<int n> struct S { };
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template<typename T> auto g(T t) -> S<f(sizeof(T))> &;
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char &f(...);
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template<typename T> auto h(T t[f(sizeof(T))]) -> decltype(&*t) {
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return t;
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}
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S<4> &k = g(0);
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int *p, *q = h(p);
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}
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namespace DataMember {
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template<typename T> struct S { static const int k; };
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const int n = S<int>::k; // expected-note {{here}}
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template<typename T> const int S<T>::k = 0;
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constexpr int m = S<int>::k; // ok
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constexpr int o = n; // expected-error {{constant expression}} expected-note {{initializer of 'n'}}
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}
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namespace Reference {
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const int k = 5;
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template<typename T> struct S {
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static volatile int &r;
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};
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template<typename T> volatile int &S<T>::r = const_cast<volatile int&>(k);
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constexpr int n = const_cast<int&>(S<int>::r);
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static_assert(n == 5, "");
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}
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