Clique in VerifyHeader checks so that the block is not block 0,
// The genesis block is the always valid dead-end
number := header.Number.Uint64()
if number == 0 {
return nil
}
whereas Ethash does not seem to do any such check, and also does things that would fail at block 0,
parent := chain.GetHeader(header.ParentHash, number-1)
if parent == nil {
return consensus.ErrUnknownAncestor
}
it seems to me that VerifyHeader is most likely not being called on the genesis block and that Clique has added an unnecessary check. Could anyone give a conclusive answer to if VerifyHeader is used for genesis block or not?
