From 839f1fa4ea2a29e983a8c93b8a0ac65fc76ba741 Mon Sep 17 00:00:00 2001
From: Pedro Pinheiro <pdpinheiro@gmail.com>
Date: Wed, 24 Feb 2016 18:36:33 +0000
Subject: [PATCH] Add assertion

Enforce the invariant that the existence of an end-of-grace-period
implies the existence of an activation hash.
---
 src/rpcblockchain.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/rpcblockchain.cpp b/src/rpcblockchain.cpp
index 1c6d25cdf28..aa547266f2c 100644
--- a/src/rpcblockchain.cpp
+++ b/src/rpcblockchain.cpp
@@ -618,7 +618,9 @@ static UniValue HardForkMajorityDesc(int minVersion, CBlockIndex* pindex, int nR
         // Always report blocks found as over the threshold once the fork is active
         nFound = nRequired + 1;
         gracePeriodEnds = static_cast<uint64_t>(forkTime);
-        triggeredAtBlock = pblocktree->ForkBitActivated(FORK_BIT_2MB).GetHex();
+        uint256 activationHash = pblocktree->ForkBitActivated(FORK_BIT_2MB);
+        assert(activationHash != uint256());
+        triggeredAtBlock = activationHash.GetHex();
     } else {
         for (int i = 0; i < consensusParams.nMajorityWindow && pstart != NULL; i++)
         {