fix sending genesis blocks to peers in syncLoop#402
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Pull request overview
This PR fixes a bug in the syncer's syncLoop function where empty BlockID entries in the history array could cause errors when attempting to send genesis blocks to peers during instant syncing scenarios.
Changes:
- Added a check to skip empty BlockID entries when iterating through history returned by
cm.History() - Prevents attempting to fetch state for empty block IDs, which would incorrectly trigger genesis state lookups with invalid heights
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chris124567
approved these changes
Feb 24, 2026
n8mgr
approved these changes
Feb 24, 2026
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The call to
s.cm.Historymay return a history that is only partially filled in when it can't fetch blocks from the store. With instant syncing this is a real possibility.We would then ask for the state of that empty block id which is the genesis state being stored with a height of
math.MaxUint64in the store. Sending that over to the peer will then show up as{"peer": "<-66.85.74.42:15724", "rpc": "SendHeaders", "error": "index 18446744073709551615::00000000 is not on our best chain"}.