From 3d05284928959220a993e640c07b3d01f59fafd4 Mon Sep 17 00:00:00 2001
From: Ng Wei Han <47109095+weiihann@users.noreply.github.com>
Date: Wed, 28 Jan 2026 18:51:02 +0800
Subject: [PATCH] trie/bintrie: fix tree key hashing to match spec (#33694)

Based on [EIP-7864](https://eips.ethereum.org/EIPS/eip-7864), the tree
index should be 32 bytes instead of 31 bytes.
```
def get_tree_key(address: Address32, tree_index: int, sub_index: int):
    # Assumes STEM_SUBTREE_WIDTH = 256
    return tree_hash(address + tree_index.to_bytes(32, "little"))[:31] + bytes(
        [sub_index]
    )
```
---
 core/genesis_test.go         | 2 +-
 trie/bintrie/key_encoding.go | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/core/genesis_test.go b/core/genesis_test.go
index 821c71feb9..ba00581b06 100644
--- a/core/genesis_test.go
+++ b/core/genesis_test.go
@@ -308,7 +308,7 @@ func TestVerkleGenesisCommit(t *testing.T) {
 		},
 	}
 
-	expected := common.FromHex("19056b480530799a4fdaa9fd9407043b965a3a5c37b4d2a1a9a4f3395a327561")
+	expected := common.FromHex("b94812c1674dcf4f2bc98f4503d15f4cc674265135bcf3be6e4417b60881042a")
 	got := genesis.ToBlock().Root().Bytes()
 	if !bytes.Equal(got, expected) {
 		t.Fatalf("invalid genesis state root, expected %x, got %x", expected, got)
diff --git a/trie/bintrie/key_encoding.go b/trie/bintrie/key_encoding.go
index 5a93fcde9a..94a22d52d0 100644
--- a/trie/bintrie/key_encoding.go
+++ b/trie/bintrie/key_encoding.go
@@ -51,6 +51,7 @@ func GetBinaryTreeKey(addr common.Address, key []byte) []byte {
 	hasher.Write(zeroHash[:12])
 	hasher.Write(addr[:])
 	hasher.Write(key[:31])
+	hasher.Write([]byte{0})
 	k := hasher.Sum(nil)
 	k[31] = key[31]
 	return k