https://gcc.gnu.org/g:1c5e1093a729223c4e50a5fd28d67b9dfe73a87c
commit r16-4396-g1c5e1093a729223c4e50a5fd28d67b9dfe73a87c Author: Yuao Ma <[email protected]> Date: Fri Oct 10 23:14:48 2025 +0800 libstdc++: Implement P2835R7 Expose std::atomic_ref's object address This patch adds the address function to __atomic_ref_base. libstdc++-v3/ChangeLog: * include/bits/atomic_base.h: Implement address(). * include/bits/version.def: Bump version number. * include/bits/version.h: Regenerate. * testsuite/29_atomics/atomic_ref/address.cc: New test. Diff: --- libstdc++-v3/include/bits/atomic_base.h | 12 +++++++ libstdc++-v3/include/bits/version.def | 4 +++ libstdc++-v3/include/bits/version.h | 7 +++- .../testsuite/29_atomics/atomic_ref/address.cc | 39 ++++++++++++++++++++++ 4 files changed, 61 insertions(+), 1 deletion(-) diff --git a/libstdc++-v3/include/bits/atomic_base.h b/libstdc++-v3/include/bits/atomic_base.h index 84661d449e25..0f3f6b1925d3 100644 --- a/libstdc++-v3/include/bits/atomic_base.h +++ b/libstdc++-v3/include/bits/atomic_base.h @@ -1589,6 +1589,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION } #endif // __glibcxx_atomic_wait +#if __glibcxx_atomic_ref >= 202411L + _GLIBCXX_ALWAYS_INLINE constexpr const _Tp* + address() const noexcept + { return _M_ptr; } +#endif // __glibcxx_atomic_ref >= 202411L + protected: _Tp* _M_ptr; }; @@ -1672,6 +1678,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION __atomic_impl::notify_all(this->_M_ptr); } #endif // __glibcxx_atomic_wait + +#if __glibcxx_atomic_ref >= 202411L + _GLIBCXX_ALWAYS_INLINE constexpr _Tp* + address() const noexcept + { return this->_M_ptr; } +#endif // __glibcxx_atomic_ref >= 202411L }; template<typename _Tp, diff --git a/libstdc++-v3/include/bits/version.def b/libstdc++-v3/include/bits/version.def index 83f1817bf8e4..1118da4b541e 100644 --- a/libstdc++-v3/include/bits/version.def +++ b/libstdc++-v3/include/bits/version.def @@ -789,6 +789,10 @@ ftms = { ftms = { name = atomic_ref; + values = { + v = 202411; + cxxmin = 26; + }; values = { v = 201806; cxxmin = 20; diff --git a/libstdc++-v3/include/bits/version.h b/libstdc++-v3/include/bits/version.h index 0d6692d244a6..c452bbeec8e0 100644 --- a/libstdc++-v3/include/bits/version.h +++ b/libstdc++-v3/include/bits/version.h @@ -880,7 +880,12 @@ #undef __glibcxx_want_atomic_lock_free_type_aliases #if !defined(__cpp_lib_atomic_ref) -# if (__cplusplus >= 202002L) +# if (__cplusplus > 202302L) +# define __glibcxx_atomic_ref 202411L +# if defined(__glibcxx_want_all) || defined(__glibcxx_want_atomic_ref) +# define __cpp_lib_atomic_ref 202411L +# endif +# elif (__cplusplus >= 202002L) # define __glibcxx_atomic_ref 201806L # if defined(__glibcxx_want_all) || defined(__glibcxx_want_atomic_ref) # define __cpp_lib_atomic_ref 201806L diff --git a/libstdc++-v3/testsuite/29_atomics/atomic_ref/address.cc b/libstdc++-v3/testsuite/29_atomics/atomic_ref/address.cc new file mode 100644 index 000000000000..42a080af55e2 --- /dev/null +++ b/libstdc++-v3/testsuite/29_atomics/atomic_ref/address.cc @@ -0,0 +1,39 @@ +// { dg-do run { target c++26 } } +// { dg-require-atomic-cmpxchg-word "" } +// { dg-add-options libatomic } + +#include <atomic> +#include <memory> +#include <type_traits> + +#include <testsuite_hooks.h> + +template <typename T> +void testAtomicRefAddress() +{ + T x(T(42)); + const std::atomic_ref<T> a(x); + + static_assert( noexcept(a.address()) ); + static_assert( std::is_same_v<decltype(a.address()), T*> ); + VERIFY( std::addressof(x) == a.address() ); +} + +template <typename T> +void testAtomicRefAddressForCV() +{ + testAtomicRefAddress<T>(); + testAtomicRefAddress<const T>(); + testAtomicRefAddress<volatile T>(); + testAtomicRefAddress<const volatile T>(); +} + +int +main () +{ + struct X { int c; }; + testAtomicRefAddressForCV<X>(); + testAtomicRefAddressForCV<int>(); + testAtomicRefAddressForCV<float>(); + testAtomicRefAddressForCV<char*>(); +}
