uintptr_t便携式替代品

T

if (((uintptr_t)&var & __alignof(T) - 1) == 0) ...

uintptr_t

std::ptrdiff_t

std::ptrdiff_t

std::ptrdiff_t

template <typename T> bool is_properly_aligned(const T* const ptr)
{
    std::ptrdiff_t diff = (ptr - static_cast<T*>(0)) * sizeof(T);
    return ((diff & __alignof(T) - 1) == 0);
}

sizeof(T)

template <typename T> bool is_properly_aligned(const T* const ptr)
{
    std::ptrdiff_t diff =
        reinterpret_cast<const char*>(ptr) - static_cast<const char*>(0);
    return ((diff & __alignof(T) - 1) == 0);
}