Matthias Wippich
27249aa2d8
This patch implements [CWG3135](https://cplusplus.github.io/CWG/issues/3135.html). This has been accepted into C++26 at the Croydon meeting through [CWG Motion 3](https://github.com/cplusplus/draft/issues/8824). This change has not been designated a defect report. However, there was recently some discussion about this designation and GCC implements it as DR. Therefore, this is treated as DR regardless.
41 lines
1023 B
C++
41 lines
1023 B
C++
// RUN: %clang_cc1 -std=c++26 -triple x86_64-linux-gnu -emit-llvm -o - %s | FileCheck %s
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namespace std {
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using size_t = decltype(sizeof(0));
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template <typename T> struct tuple_size;
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template <size_t I, typename T> struct tuple_element;
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template <typename T> struct tuple_size<const T> : tuple_size<T> {};
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template <size_t I, typename T> struct tuple_element<I, const T> {
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using type = const typename tuple_element<I, T>::type;
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};
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} // namespace std
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using u8 = unsigned char;
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template <u8 N> struct Range {
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template <std::size_t I>
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constexpr friend u8 get(Range) noexcept {
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return I;
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}
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};
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namespace std {
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template <u8 N> struct tuple_size<Range<N>> {
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static constexpr std::size_t value = N;
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};
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template <std::size_t I, u8 N> struct tuple_element<I, Range<N>> {
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using type = u8;
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};
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} // namespace std
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const u8 &f() {
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static constexpr auto [I] = Range<1>();
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return I;
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}
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// CHECK: @[[TMP:_ZZ1fvE1I]] = internal constant i8 0, align 1
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// CHECK-LABEL: define {{.*}} @_Z1fv(
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// CHECK: ret ptr @[[TMP]]
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