Index: include/array =================================================================== --- include/array +++ include/array @@ -118,6 +118,55 @@ _LIBCPP_BEGIN_NAMESPACE_STD template +struct __array_traits { + typedef _Tp _StorageT[_Size]; + + _LIBCPP_INLINE_VISIBILITY + static _LIBCPP_CONSTEXPR_AFTER_CXX14 _Tp* __data(_StorageT& __store) { + return __store; + } + + _LIBCPP_INLINE_VISIBILITY + static _LIBCPP_CONSTEXPR_AFTER_CXX14 _Tp const* __data(const _StorageT& __store) { + return __store; + } + + _LIBCPP_INLINE_VISIBILITY + static void __swap(_StorageT& __lhs, _StorageT& __rhs) { + std::swap_ranges(__lhs, __lhs + _Size, __rhs); + } + + _LIBCPP_INLINE_VISIBILITY + static void __fill(_StorageT& __arr, _Tp const& __val) { + _VSTD::fill_n(__arr, _Size, __val); + } +}; + +template +struct __array_traits<_Tp, 0> { + typedef typename aligned_storage::value>::type _StorageT; + + _LIBCPP_INLINE_VISIBILITY + static _Tp* __data(_StorageT& __store) { + _StorageT *__ptr = std::addressof(__store); + return reinterpret_cast<_Tp*>(__ptr); + } + + _LIBCPP_INLINE_VISIBILITY + static const _Tp* __data(const _StorageT& __store) { + const _StorageT *__ptr = std::addressof(__store); + return reinterpret_cast(__ptr); + } + + _LIBCPP_INLINE_VISIBILITY + static void __swap(_StorageT&, _StorageT&) {} + + _LIBCPP_INLINE_VISIBILITY + static void __fill(_StorageT&, _Tp const&) { + } +}; + +template struct _LIBCPP_TEMPLATE_VIS array { // types: @@ -134,31 +183,26 @@ typedef std::reverse_iterator reverse_iterator; typedef std::reverse_iterator const_reverse_iterator; - value_type __elems_[_Size > 0 ? _Size : 1]; + typedef __array_traits<_Tp, _Size> _Traits; + typename _Traits::_StorageT __elems_; // No explicit construct/copy/destroy for aggregate type _LIBCPP_INLINE_VISIBILITY void fill(const value_type& __u) - {_VSTD::fill_n(__elems_, _Size, __u);} - _LIBCPP_INLINE_VISIBILITY - void swap(array& __a) _NOEXCEPT_(_Size == 0 || __is_nothrow_swappable<_Tp>::value) - { __swap_dispatch((std::integral_constant()), __a); } + {_Traits::__fill(__elems_, __u);} _LIBCPP_INLINE_VISIBILITY - void __swap_dispatch(std::true_type, array&) {} - - _LIBCPP_INLINE_VISIBILITY - void __swap_dispatch(std::false_type, array& __a) - { _VSTD::swap_ranges(__elems_, __elems_ + _Size, __a.__elems_);} + void swap(array& __a) _NOEXCEPT_(_Size == 0 || __is_nothrow_swappable<_Tp>::value) + { _Traits::__swap(__elems_, __a.__elems_); } // iterators: _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 - iterator begin() _NOEXCEPT {return iterator(__elems_);} + iterator begin() _NOEXCEPT {return iterator(data());} _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 - const_iterator begin() const _NOEXCEPT {return const_iterator(__elems_);} + const_iterator begin() const _NOEXCEPT {return const_iterator(data());} _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 - iterator end() _NOEXCEPT {return iterator(__elems_ + _Size);} + iterator end() _NOEXCEPT {return iterator(data() + _Size);} _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 - const_iterator end() const _NOEXCEPT {return const_iterator(__elems_ + _Size);} + const_iterator end() const _NOEXCEPT {return const_iterator(data() + _Size);} _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 reverse_iterator rbegin() _NOEXCEPT {return reverse_iterator(end());} @@ -201,9 +245,9 @@ _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 - value_type* data() _NOEXCEPT {return __elems_;} + value_type* data() _NOEXCEPT {return _Traits::__data(__elems_);} _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 - const value_type* data() const _NOEXCEPT {return __elems_;} + const value_type* data() const _NOEXCEPT {return _Traits::__data(__elems_);} }; template Index: test/std/containers/sequences/array/array.cons/default.pass.cpp =================================================================== --- test/std/containers/sequences/array/array.cons/default.pass.cpp +++ test/std/containers/sequences/array/array.cons/default.pass.cpp @@ -14,6 +14,14 @@ #include #include +// std::array is explicitly allowed to be initialized with A a = { init-list };. +// Disable the missing braces warning for this reason. +#include "disable_missing_braces_warning.h" + +struct NoDefault { + NoDefault(int) {} +}; + int main() { { @@ -28,4 +36,13 @@ C c; assert(c.size() == 0); } + { + typedef std::array C; + C c; + assert(c.size() == 0); + C c1 = {}; + assert(c1.size() == 0); + C c2 = {{}}; + assert(c2.size() == 0); + } } Index: test/std/containers/sequences/array/array.data/data.pass.cpp =================================================================== --- test/std/containers/sequences/array/array.data/data.pass.cpp +++ test/std/containers/sequences/array/array.data/data.pass.cpp @@ -36,4 +36,14 @@ T* p = c.data(); (void)p; // to placate scan-build } + { + struct NoDefault { + NoDefault(int) {} + }; + typedef NoDefault T; + typedef std::array C; + C c = {}; + T* p = c.data(); + assert(p != nullptr); + } } Index: test/std/containers/sequences/array/array.data/data_const.pass.cpp =================================================================== --- test/std/containers/sequences/array/array.data/data_const.pass.cpp +++ test/std/containers/sequences/array/array.data/data_const.pass.cpp @@ -38,6 +38,16 @@ const T* p = c.data(); (void)p; // to placate scan-build } + { + struct NoDefault { + NoDefault(int) {} + }; + typedef NoDefault T; + typedef std::array C; + const C c = {}; + const T* p = c.data(); + assert(p != nullptr); + } #if TEST_STD_VER > 14 { typedef std::array C; Index: test/std/containers/sequences/array/begin.pass.cpp =================================================================== --- test/std/containers/sequences/array/begin.pass.cpp +++ test/std/containers/sequences/array/begin.pass.cpp @@ -31,4 +31,13 @@ *i = 5.5; assert(c[0] == 5.5); } + { + struct NoDefault { + NoDefault(int) {} + }; + typedef NoDefault T; + typedef std::array C; + C c = {}; + assert(c.begin() == c.end()); + } }