Implement variadic lock_guard. Summary: This patch implements the variadic `lock_guard` paper. Making `lock_guard` variadic is a ABI breaking change because the specialization `lock_guard<_Mutex>` mangles differently then when it was the primary template. This change only provides variadic `lock_guard` in ABI V2 or when `_LIBCPP_ABI_VARIADIC_LOCK_GUARD` is defined. Note that in ABI V2 `lock_guard` must always be declared as a variadic template, even in C++03, in order to keep the ABI consistent. For this reason `lock_guard` is forward declared as a variadic template in all standard dialects and therefore depends on variadic templates being provided as an extension in C++03. All supported versions of Clang and GCC provide this extension. Reviewers: mclow.lists Subscribers: K-ballo, mclow.lists, cfe-commits Differential Revision: http://reviews.llvm.org/D21260 git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@272634 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/__mutex_base b/include/__mutex_base index 32536a6..bb70a15 100644 --- a/include/__mutex_base +++ b/include/__mutex_base
@@ -76,8 +76,21 @@ #endif + +// Forward declare lock_guard as a variadic template even in C++03 to keep +// the mangling consistent between dialects. +#if defined(_LIBCPP_ABI_VARIADIC_LOCK_GUARD) +template <class ..._Mutexes> +class _LIBCPP_TYPE_VIS_ONLY lock_guard; +#endif + template <class _Mutex> -class _LIBCPP_TYPE_VIS_ONLY _LIBCPP_THREAD_SAFETY_ANNOTATION(scoped_lockable) lock_guard +class _LIBCPP_TYPE_VIS_ONLY _LIBCPP_THREAD_SAFETY_ANNOTATION(scoped_lockable) +#if !defined(_LIBCPP_ABI_VARIADIC_LOCK_GUARD) +lock_guard +#else +lock_guard<_Mutex> +#endif { public: typedef _Mutex mutex_type; @@ -96,8 +109,8 @@ ~lock_guard() _LIBCPP_THREAD_SAFETY_ANNOTATION(release_capability()) {__m_.unlock();} private: - lock_guard(lock_guard const&);// = delete; - lock_guard& operator=(lock_guard const&);// = delete; + lock_guard(lock_guard const&) _LIBCPP_EQUAL_DELETE; + lock_guard& operator=(lock_guard const&) _LIBCPP_EQUAL_DELETE; }; template <class _Mutex> 