Is CRC32 additive?

Question

On several places I\'ve read that crc32 is additive and so: CRC(A xor B) = CRC(A) xor CRC(B).

The above statement was disproven by the following code I wrote:

<

Answer 1

This would imply that each bit position of the CRC result is only driven by the equivalent bit position in the input. Consider your example with B == 0.

The relationship you're describing is more likely to be true for some primitive xor or additive checksum algorithms.