32 lines
924 B
C++
32 lines
924 B
C++
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// RUN: %clang_cc1 -fsyntax-only -verify -std=c++2a %s
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template <typename T1, typename T2> struct is_same {
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static constexpr bool value = false;
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};
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template <typename T> struct is_same<T, T> {
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static constexpr bool value = true;
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};
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template <class T, class U>
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concept SameHelper = is_same<T, U>::value;
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template <class T, class U>
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concept same_as = SameHelper<T, U> && SameHelper<U, T>;
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namespace deferred_instantiation {
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template <class X> constexpr X do_not_instantiate() { return nullptr; }
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struct T {
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template <same_as<float> X> explicit(do_not_instantiate<X>()) T(X) {}
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T(int) {}
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};
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T t(5);
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// expected-error@17{{cannot initialize}}
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// expected-note@20{{in instantiation of function template specialization}}
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// expected-note@30{{while substituting deduced template arguments}}
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// expected-note@30{{in instantiation of function template specialization}}
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T t2(5.0f);
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} // namespace deferred_instantiation
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