All your variables are not 64-bit aligned. An array of 16-bit integers will generally use 16 bits (2 bytes) per integer. So will two or more subsequent integers

All your variables are not 64-bit aligned. An array of 16-bit integers will generally use 16 bits (2 bytes) per integer. So will two or more subsequent integers in a struct. In general, variables smaller than the alignment of the CPU (but still power of two sizes) only need to be aligned to their own size.