Skip to content

core: assign default difficulty to zero for chain without ethash #31067

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
fjl merged 2 commits into from
Feb 4, 2025
Merged

core: assign default difficulty to zero for chain without ethash #31067

Changes from 1 commit
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
e65c08f
core: assign default difficulty to zero for chain without ethash
fjl Jan 23, 2025
9e31c48
core: fix genesis test by adding ethash config
lightclient Feb 4, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
8 changes: 6 additions & 2 deletions core/genesis.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -459,8 +459,12 @@ func (g *Genesis) toBlockWithRoot(root common.Hash) *types.Block {
if g.GasLimit == 0 {
head.GasLimit = params.GenesisGasLimit
}
if g.Difficulty == nil && g.Mixhash == (common.Hash{}) {
Copy link
Member

@rjl493456442 rjl493456442 Jan 23, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

QQ, Why the g.MixHash == (common.Hash{}) is a condition for setting the genesis difficulty?

Copy link
Contributor Author

@fjl fjl Jan 23, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I don't get it either. This code is very old.

Copy link
Contributor Author

@fjl fjl Jan 23, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

It was added in the PR that also added the RANDOM opcode. https://github.com/ethereum/go-ethereum/pull/24141/files#diff-1272116434e5549f278a940767af52ed2d1abc91c44fa04ec48d8835a3774036

@MariusVanDerWijden might know more.

Copy link
Contributor Author

@fjl fjl Jan 23, 2025 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I think it might be related with the idea of how the header MixDigest is used. After the merge, this field was repurposed for the random value. What @MariusVanDerWijden may have been thinking is: "if Mixhash is set in genesis, it means the genesis block is supposed to have a random value (signaling the merge), and thus difficulty will be set to zero."

Copy link
Member

@MariusVanDerWijden MariusVanDerWijden Jan 30, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Yes I think that was it. It fixed a test case from the testing team if I remember correctly

head.Difficulty = params.GenesisDifficulty
if g.Difficulty == nil {
if g.Config != nil && g.Config.Ethash == nil {
head.Difficulty = big.NewInt(0)
} else if g.Mixhash == (common.Hash{}) {
head.Difficulty = params.GenesisDifficulty
}
}
if g.Config != nil && g.Config.IsLondon(common.Big0) {
if g.BaseFee != nil {
Expand Down
Loading