From 62d7a25ccbd4be65e567304b13cf25d1536fd937 Mon Sep 17 00:00:00 2001
From: Jordi Baylina <jordi@baylina.cat>
Date: Wed, 7 Sep 2022 18:17:42 +0200
Subject: [PATCH] Fix circuit Zero linearhashes

---
 circuits.bn128/linearhash.circom | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/circuits.bn128/linearhash.circom b/circuits.bn128/linearhash.circom
index d2c0cbfd..a15e9ed3 100644
--- a/circuits.bn128/linearhash.circom
+++ b/circuits.bn128/linearhash.circom
@@ -26,15 +26,20 @@ template LinearHash(nInputs, eSize) {
         nHashes = (nElements256 - 1)\16 +1;
     }
 
-    component hash[nHashes-1];
-    var nLastHash = nElements256 - (nHashes - 1)*16;
-    component lastHash = PoseidonEx(nLastHash, 1);
+    component hash[nHashes>0 ? nHashes-1 : 0];
+    var nLastHash;
+    component lastHash;
 
 
     for (var i=0; i<nHashes-1; i++) {
         hash[i] = PoseidonEx(16, 1);
     }
 
+    if (nHashes>0) {
+        nLastHash = nElements256 - (nHashes - 1)*16;
+        lastHash = PoseidonEx(nLastHash, 1);
+    }
+
     var curHash =0;
     var curHashIdx = 0;