Fix UB with bench on genesis block

src/validation.cpp

@@ -1834,6 +1834,8 @@ bool CChainState::ConnectBlock(const CBlock& block, CValidationState& state, CBl
     uint256 hashPrevBlock = pindex->pprev == nullptr ? uint256() : pindex->pprev->GetBlockHash();
     assert(hashPrevBlock == view.GetBestBlock());
 
+    nBlocksTotal++;
+
     // Special case for the genesis block, skipping connection of its transactions
     // (its coinbase is unspendable)
     if (block.GetHash() == chainparams.GetConsensus().hashGenesisBlock) {
@@ -1842,8 +1844,6 @@ bool CChainState::ConnectBlock(const CBlock& block, CValidationState& state, CBl
         return true;
     }
 
-    nBlocksTotal++;
-
     bool fScriptChecks = true;
     if (!hashAssumeValid.IsNull()) {
         // We've been configured with the hash of a block which has been externally verified to have a valid history.
@@ -2445,6 +2445,7 @@ bool CChainState::ConnectTip(CValidationState& state, const CChainParams& chainp
             return error("%s: ConnectBlock %s failed, %s", __func__, pindexNew->GetBlockHash().ToString(), FormatStateMessage(state));
         }
         nTime3 = GetTimeMicros(); nTimeConnectTotal += nTime3 - nTime2;
+        assert(nBlocksTotal > 0);
         LogPrint(BCLog::BENCH, "  - Connect total: %.2fms [%.2fs (%.2fms/blk)]\n", (nTime3 - nTime2) * MILLI, nTimeConnectTotal * MICRO, nTimeConnectTotal * MILLI / nBlocksTotal);
         bool flushed = view.Flush();
         assert(flushed);