Clang and GCC both have new atomic built-ins that can be used for implementing C11 or C++11 atomics. You can use them whether or not you have C++11 support. B

Clang and GCC both have new atomic built-ins that can be used for implementing C11 or C++11 atomics. You can use them whether or not you have C++11 support. But I don't see much inline asm for SIMD ops. Almost every piece of SIMD code I see uses either intrinsics or writes the whole function in assembly.