From e2f36a475245855826b907319becd0616ef9c329 Mon Sep 17 00:00:00 2001
From: hepengfei <hpf@hackerful.cn>
Date: Thu, 20 Jun 2019 20:40:29 +0800
Subject: [PATCH] core: block may be nil in block.Hash()

---
 core/genesis.go | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/core/genesis.go b/core/genesis.go
index 830fb033b8..cab9c645db 100644
--- a/core/genesis.go
+++ b/core/genesis.go
@@ -183,7 +183,11 @@ func SetupGenesisBlockWithOverride(db ethdb.Database, genesis *Genesis, constant
 			return genesis.Config, hash, &GenesisMismatchError{stored, hash}
 		}
 		block, err := genesis.Commit(db)
-		return genesis.Config, block.Hash(), err
+		var hash common.Hash
+		if block != nil {
+			hash = block.Hash()
+		}
+		return genesis.Config, hash, err
 	}
 
 	// Check whether the genesis block is already written.