From 6e950e43e16132d72775e0b4b36d44d73ae64873 Mon Sep 17 00:00:00 2001
From: Gary Rong <garyrong0905@gmail.com>
Date: Fri, 21 Jan 2022 14:35:52 +0800
Subject: [PATCH] miner: use empty zero randomness for pending blocks after the
 merge

---
 miner/worker.go      | 11 +----------
 miner/worker_test.go |  6 +-----
 2 files changed, 2 insertions(+), 15 deletions(-)

diff --git a/miner/worker.go b/miner/worker.go
index c147267f1157d..2b4c574da2420 100644
--- a/miner/worker.go
+++ b/miner/worker.go
@@ -20,7 +20,6 @@ import (
 	"errors"
 	"fmt"
 	"math/big"
-	"math/rand"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -998,17 +997,9 @@ func (w *worker) prepareWork(genParams *generateParams) (*environment, error) {
 	if !genParams.noExtra && len(w.extra) != 0 {
 		header.Extra = w.extra
 	}
-	// Set the randomness field for post-merge blocks, either fed by beacon chain
-	// or generated locally.
+	// Set the randomness field from the beacon chain if it's available.
 	if genParams.random != (common.Hash{}) {
 		header.MixDigest = genParams.random
-	} else if w.isTTDReached(header) {
-		random := make([]byte, common.HashLength)
-		_, err := rand.Read(random)
-		if err != nil {
-			return nil, err
-		}
-		header.MixDigest = common.BytesToHash(random)
 	}
 	// Set baseFee and GasLimit if we are on an EIP-1559 chain
 	if w.chainConfig.IsLondon(header.Number) {
diff --git a/miner/worker_test.go b/miner/worker_test.go
index 1afcc0d08786d..dbc8ebad69328 100644
--- a/miner/worker_test.go
+++ b/miner/worker_test.go
@@ -580,11 +580,7 @@ func testGetSealingWork(t *testing.T, chainConfig *params.ChainConfig, engine co
 				t.Error("Unexpected coinbase")
 			}
 		}
-		if postMerge && random == (common.Hash{}) {
-			if block.MixDigest() == (common.Hash{}) {
-				t.Error("Unexpected mix digest")
-			}
-		} else if !isClique {
+		if !isClique {
 			if block.MixDigest() != random {
 				t.Error("Unexpected mix digest")
 			}