diff options
| author | Ville Voutilainen <ville.voutilainen@gmail.com> | 2016-12-06 14:47:54 +0200 |
|---|---|---|
| committer | Ville Voutilainen <ville@gcc.gnu.org> | 2016-12-06 14:47:54 +0200 |
| commit | 1637d42545cced0c58204ecb36499e512eeb3841 (patch) | |
| tree | e2e0634ffd2caefd6431cc83be8f28d78555af84 | |
| parent | b01af236b7d0d92cf1e9d642495d9177347bd740 (diff) | |
| download | gcc-1637d42545cced0c58204ecb36499e512eeb3841.zip gcc-1637d42545cced0c58204ecb36499e512eeb3841.tar.gz gcc-1637d42545cced0c58204ecb36499e512eeb3841.tar.bz2 | |
Constrain optional's __constexpr_addressof in its return type and use a constexpr addressof for optional, if available.
Constrain optional's __constexpr_addressof in its return type
and use a constexpr addressof for optional, if available.
* include/experimental/optional (__constexpr_addressof):
Constrain in the return type instead of in a template parameter.
(_Has_addressof_mem)
(_Has_addressof_free, _Has_addressof, __constexpr_addressof):
Guard with #ifndef __cpp_lib_addressof_constexpr.
(operator->()): Use std::__addressof if it's constexpr.
From-SVN: r243298
| -rw-r--r-- | libstdc++-v3/ChangeLog | 11 | ||||
| -rw-r--r-- | libstdc++-v3/include/experimental/optional | 22 |
2 files changed, 28 insertions, 5 deletions
diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index 1d47e38..47e9abf 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,3 +1,14 @@ +2016-12-06 Ville Voutilainen <ville.voutilainen@gmail.com> + + Constrain optional's __constexpr_addressof in its return type + and use a constexpr addressof for optional, if available. + * include/experimental/optional (__constexpr_addressof): + Constrain in the return type instead of in a template parameter. + (_Has_addressof_mem) + (_Has_addressof_free, _Has_addressof, __constexpr_addressof): + Guard with #ifndef __cpp_lib_addressof_constexpr. + (operator->()): Use std::__addressof if it's constexpr. + 2016-11-27 Tim Shen <timshen@google.com> * include/std/variant (visit): Make visit constexpr. Also cleanup diff --git a/libstdc++-v3/include/experimental/optional b/libstdc++-v3/include/experimental/optional index a631158..6994e77 100644 --- a/libstdc++-v3/include/experimental/optional +++ b/libstdc++-v3/include/experimental/optional @@ -134,6 +134,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION __throw_bad_optional_access(const char* __s) { _GLIBCXX_THROW_OR_ABORT(bad_optional_access(__s)); } +#ifndef __cpp_lib_addressof_constexpr template<typename _Tp, typename = void> struct _Has_addressof_mem : std::false_type { }; @@ -170,16 +171,21 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION * overloaded addressof operator (unary operator&), in which case the call * will not be a constant expression. */ - template<typename _Tp, enable_if_t<!_Has_addressof<_Tp>::value, int>...> - constexpr _Tp* __constexpr_addressof(_Tp& __t) + template<typename _Tp> + constexpr + enable_if_t<!_Has_addressof<_Tp>::value, _Tp*> + __constexpr_addressof(_Tp& __t) { return &__t; } /** * @brief Fallback overload that defers to __addressof. */ - template<typename _Tp, enable_if_t<_Has_addressof<_Tp>::value, int>...> - inline _Tp* __constexpr_addressof(_Tp& __t) + template<typename _Tp> + inline + enable_if_t<_Has_addressof<_Tp>::value, _Tp*> + __constexpr_addressof(_Tp& __t) { return std::__addressof(__t); } +#endif // __cpp_lib_addressof_constexpr /** * @brief Class template that holds the necessary state for @ref optional @@ -705,7 +711,13 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION // [X.Y.4.5] Observers. constexpr const _Tp* operator->() const - { return __constexpr_addressof(this->_M_get()); } + { +#ifndef __cpp_lib_addressof_constexpr + return __constexpr_addressof(this->_M_get()); +#else + return std::__addressof(this->_M_get()); +#endif + } _Tp* operator->() |