Function DoNotOptimizeAway

util/system/compiler.h:644–655

template <typename T>
Y_FORCE_INLINE void DoNotOptimizeAway(T&& datum) {
    #if defined(_MSC_VER)
    UseCharPointerImpl(&reinterpret_cast<volatile const char&>(datum));
    _ReadWriteBarrier();
    #elif defined(__GNUC__) && defined(_x86_)
    asm volatile(""
                 :
                 : "X"(datum));
    #else
    Y_FAKE_READ(datum);
    #endif
}

/**
 * The usage for `const T&` is prohibited.