diff options
Diffstat (limited to 'boost/atomic/detail/config.hpp')
-rw-r--r-- | boost/atomic/detail/config.hpp | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/boost/atomic/detail/config.hpp b/boost/atomic/detail/config.hpp index 00f7bff696..7a43e23cbc 100644 --- a/boost/atomic/detail/config.hpp +++ b/boost/atomic/detail/config.hpp @@ -73,4 +73,30 @@ #define BOOST_ATOMIC_DETAIL_NO_ASM_RAX_RDX_PAIRS #endif +#if defined(BOOST_NO_CXX11_HDR_TYPE_TRAITS) +#if !(defined(BOOST_LIBSTDCXX11) && (BOOST_LIBSTDCXX_VERSION+0) >= 40700) /* libstdc++ from gcc >= 4.7 in C++11 mode */ +// This macro indicates that there is no <type_traits> standard header that is sufficient for Boost.Atomic needs. +#define BOOST_ATOMIC_DETAIL_NO_CXX11_HDR_TYPE_TRAITS +#endif +#endif // defined(BOOST_NO_CXX11_HDR_TYPE_TRAITS) + +// Enable pointer/reference casts between storage and value when possible. +// Note: Despite that MSVC does not employ strict aliasing rules for optimizations +// and does not require an explicit markup for types that may alias, we still don't +// enable the optimization for this compiler because at least MSVC-8 and 9 are known +// to generate broken code sometimes when casts are used. +#if defined(__GNUC__) && (!defined(BOOST_INTEL_CXX_VERSION) || (BOOST_INTEL_CXX_VERSION+0) >= 1300) +#define BOOST_ATOMIC_DETAIL_MAY_ALIAS __attribute__((__may_alias__)) +#define BOOST_ATOMIC_DETAIL_STORAGE_TYPE_MAY_ALIAS +#elif defined(__has_attribute) +#if __has_attribute(__may_alias__) +#define BOOST_ATOMIC_DETAIL_MAY_ALIAS __attribute__((__may_alias__)) +#define BOOST_ATOMIC_DETAIL_STORAGE_TYPE_MAY_ALIAS +#endif +#endif + +#if !defined(BOOST_ATOMIC_DETAIL_MAY_ALIAS) +#define BOOST_ATOMIC_DETAIL_MAY_ALIAS +#endif + #endif // BOOST_ATOMIC_DETAIL_CONFIG_HPP_INCLUDED_ |