From ba9dccd902a8276e17a066e9e635fb2cc9a34d1f Mon Sep 17 00:00:00 2001 From: Eric Fiselier Date: Sat, 18 Jun 2016 02:12:53 +0000 Subject: [PATCH] Enable building and using atomic shared_ptr for GCC. Summary: Currently the implementation of [util.smartptr.shared.atomic] is provided only when using Clang, and not with GCC. This is a relic of not having a GCC implementation of , even though isn't actually used in the implementation. This patch enables support for atomic shared_ptr functions when using GCC. Note that this is not a header only change. Previously only Clang builds of libc++.so would provide the required symbols. There is no reason for this restriction. After this change both Clang and GCC builds should be binary compatible with each other WRT these symbols. Reviewers: mclow.lists, rmaprath, EricWF Subscribers: cfe-commits Differential Revision: http://reviews.llvm.org/D21407 git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@273076 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/memory | 7 +++---- src/memory.cpp | 4 ++-- 2 files changed, 5 insertions(+), 6 deletions(-) diff --git a/include/memory b/include/memory index 8324d1c5f..587d3059e 100644 --- a/include/memory +++ b/include/memory @@ -5464,9 +5464,8 @@ inline _LIBCPP_INLINE_VISIBILITY basic_ostream<_CharT, _Traits>& operator<<(basic_ostream<_CharT, _Traits>& __os, shared_ptr<_Yp> const& __p); -// TODO(EricWF): Enable this for both Clang and GCC. Currently it is only -// enabled with clang. -#if defined(_LIBCPP_HAS_C_ATOMIC_IMP) && !defined(_LIBCPP_HAS_NO_THREADS) + +#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER) class _LIBCPP_TYPE_VIS __sp_mut { @@ -5595,7 +5594,7 @@ atomic_compare_exchange_weak_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v return atomic_compare_exchange_weak(__p, __v, __w); } -#endif // defined(_LIBCPP_HAS_C_ATOMIC_IMP) && !defined(_LIBCPP_HAS_NO_THREADS) +#endif // !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER) //enum class struct _LIBCPP_TYPE_VIS pointer_safety diff --git a/src/memory.cpp b/src/memory.cpp index 08f2259b8..15e947fc0 100644 --- a/src/memory.cpp +++ b/src/memory.cpp @@ -124,7 +124,7 @@ __shared_weak_count::__get_deleter(const type_info&) const _NOEXCEPT #endif // _LIBCPP_NO_RTTI -#if defined(_LIBCPP_HAS_C_ATOMIC_IMP) && !defined(_LIBCPP_HAS_NO_THREADS) +#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER) static const std::size_t __sp_mut_count = 16; static __libcpp_mutex_t mut_back_imp[__sp_mut_count] = @@ -177,7 +177,7 @@ __get_sp_mut(const void* p) return muts[hash()(p) & (__sp_mut_count-1)]; } -#endif // defined(_LIBCPP_HAS_C_ATOMIC_IMP) && !defined(_LIBCPP_HAS_NO_THREADS) +#endif // !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER) void declare_reachable(void*)