From 74f29c27372cb88e7f4a6f14ee40b699e3c58eb0 Mon Sep 17 00:00:00 2001
From: 21E14 <21xe14@gmail.com>
Date: Mon, 27 Oct 2014 23:00:55 -0400
Subject: [PATCH] Check pindexBestForkBase for null

Rebased-From: 730b1ed1a0d2b2b0f278ee808e7e266a50fac94b
Github-Pull: #5154
---
 src/main.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/main.cpp b/src/main.cpp
index 6430ca04fd..a42bb8a6b0 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1367,13 +1367,13 @@ void CheckForkWarningConditions()
 
     if (pindexBestForkTip || (pindexBestInvalid && pindexBestInvalid->nChainWork > chainActive.Tip()->nChainWork + (chainActive.Tip()->GetBlockWork() * 6).getuint256()))
     {
-        if (!fLargeWorkForkFound)
+        if (!fLargeWorkForkFound && pindexBestForkBase)
         {
             std::string warning = std::string("'Warning: Large-work fork detected, forking after block ") +
                 pindexBestForkBase->phashBlock->ToString() + std::string("'");
             CAlert::Notify(warning, true);
         }
-        if (pindexBestForkTip)
+        if (pindexBestForkTip && pindexBestForkBase)
         {
             LogPrintf("CheckForkWarningConditions: Warning: Large valid fork found\n  forking the chain at height %d (%s)\n  lasting to height %d (%s).\nChain state database corruption likely.\n",
                    pindexBestForkBase->nHeight, pindexBestForkBase->phashBlock->ToString(),