Implement the missing constexpr stuff in <array>. Fixes PR#31645.

llvm-svn: 292091
This commit is contained in:
Marshall Clow 2017-01-16 03:02:10 +00:00
parent c9807c3370
commit e78269506f
4 changed files with 62 additions and 8 deletions

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@ -185,14 +185,17 @@ struct _LIBCPP_TEMPLATE_VIS array
_LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT {return _Size == 0;}
// element access:
_LIBCPP_INLINE_VISIBILITY reference operator[](size_type __n) {return __elems_[__n];}
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference operator[](size_type __n) const {return __elems_[__n];}
reference at(size_type __n);
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
reference operator[](size_type __n) {return __elems_[__n];}
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
const_reference operator[](size_type __n) const {return __elems_[__n];}
_LIBCPP_CONSTEXPR_AFTER_CXX14 reference at(size_type __n);
_LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference at(size_type __n) const;
_LIBCPP_INLINE_VISIBILITY reference front() {return __elems_[0];}
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 reference front() {return __elems_[0];}
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference front() const {return __elems_[0];}
_LIBCPP_INLINE_VISIBILITY reference back() {return __elems_[_Size > 0 ? _Size-1 : 0];}
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 reference back() {return __elems_[_Size > 0 ? _Size-1 : 0];}
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference back() const {return __elems_[_Size > 0 ? _Size-1 : 0];}
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
@ -202,6 +205,7 @@ struct _LIBCPP_TEMPLATE_VIS array
};
template <class _Tp, size_t _Size>
_LIBCPP_CONSTEXPR_AFTER_CXX14
typename array<_Tp, _Size>::reference
array<_Tp, _Size>::at(size_type __n)
{

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@ -23,6 +23,14 @@
// Disable the missing braces warning for this reason.
#include "disable_missing_braces_warning.h"
#if TEST_STD_VER > 14
constexpr bool check_idx( size_t idx, double val )
{
std::array<double, 3> arr = {1, 2, 3.5};
return arr.at(idx) == val;
}
#endif
int main()
{
{
@ -82,4 +90,11 @@ int main()
}
#endif
#if TEST_STD_VER > 14
{
static_assert (check_idx(0, 1), "");
static_assert (check_idx(1, 2), "");
static_assert (check_idx(2, 3.5), "");
}
#endif
}

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@ -9,10 +9,10 @@
// <array>
// reference front();
// reference back();
// reference front(); // constexpr in C++17
// reference back(); // constexpr in C++17
// const_reference front(); // constexpr in C++14
// const_reference back(); // constexpr in C++14
// const_reference back(); // constexpr in C++14
#include <array>
#include <cassert>
@ -23,6 +23,20 @@
// Disable the missing braces warning for this reason.
#include "disable_missing_braces_warning.h"
#if TEST_STD_VER > 14
constexpr bool check_front( double val )
{
std::array<double, 3> arr = {1, 2, 3.5};
return arr.front() == val;
}
constexpr bool check_back( double val )
{
std::array<double, 3> arr = {1, 2, 3.5};
return arr.back() == val;
}
#endif
int main()
{
{
@ -65,4 +79,10 @@ int main()
}
#endif
#if TEST_STD_VER > 14
{
static_assert (check_front(1), "");
static_assert (check_back (3.5), "");
}
#endif
}

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@ -23,6 +23,14 @@
// Disable the missing braces warning for this reason.
#include "disable_missing_braces_warning.h"
#if TEST_STD_VER > 14
constexpr bool check_idx( size_t idx, double val )
{
std::array<double, 3> arr = {1, 2, 3.5};
return arr[idx] == val;
}
#endif
int main()
{
{
@ -63,4 +71,11 @@ int main()
}
#endif
#if TEST_STD_VER > 14
{
static_assert (check_idx(0, 1), "");
static_assert (check_idx(1, 2), "");
static_assert (check_idx(2, 3.5), "");
}
#endif
}