From cf94e03ac65854c34aaacd5ec17c6c357454f917 Mon Sep 17 00:00:00 2001
From: jl777 <jameslee777@yahoo.com>
Date: Mon, 5 Aug 2019 05:46:15 -1100
Subject: [PATCH] Fix null block access

---
 src/pow.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/pow.cpp b/src/pow.cpp
index 0dabfb11e..ba7c1d91e 100644
--- a/src/pow.cpp
+++ b/src/pow.cpp
@@ -282,7 +282,7 @@ unsigned int GetNextWorkRequired(const CBlockIndex* pindexLast, const CBlockHead
             }
             fprintf(stderr," cmp.%d mult.%d for ht.%d\n",mult>1,(int32_t)mult,(int32_t)pindexLast->GetHeight()+1);
         }
-        else
+        else if ( pblock != 0 )
         {
             // bnTarget = RT_CST_RST (bnTarget, ts, cw, numerator, denominator, W, T, past);
             bnTarget = RT_CST_RST(pblock->nTime,bnTarget,ts,ct,1,2,3,50);