From a8f5005a7f81219bffb017c82486392c6e9b2c31 Mon Sep 17 00:00:00 2001
From: jl777 <jameslee777@yahoo.com>
Date: Thu, 1 Aug 2019 09:54:24 -1100
Subject: [PATCH] Fix crash

---
 src/pow.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/pow.cpp b/src/pow.cpp
index 19eb28629..a91b48dc1 100644
--- a/src/pow.cpp
+++ b/src/pow.cpp
@@ -74,7 +74,9 @@ unsigned int GetNextWorkRequired(const CBlockIndex* pindexLast, const CBlockHead
     // Find the first block in the averaging interval
     const CBlockIndex* pindexFirst = pindexLast;
     arith_uint256 bnTarget,bnTot {0};
-    uint32_t nbits; int64_t diff,mult = pblock->nTime - pindexFirst->nTime - 7 * ASSETCHAINS_BLOCKTIME;
+    uint32_t nbits; int64_t diff,mult = 0;
+    if ( pindexFirst != 0 )
+        mult = pblock->nTime - pindexFirst->nTime - 7 * ASSETCHAINS_BLOCKTIME;
     for (int i = 0; pindexFirst && i < params.nPowAveragingWindow; i++)
     {
         arith_uint256 bnTmp;