Hi, I am using something like this: struct S1 { int index __attribute__((aligned(CACHE_LINE_SIZE))); struct S2 some_other; }; I am not using anything like `#pragma pack`. I am wondering whether adding that `__attribute__((aligned(CACHE_LINE_SIZE)))` will break GCC's automatic alignment for S1 and S2. Can anyone point me to any document which specify this behavior? Thanks, Yubin