Fix miner for 4MB blocks

src/miner.cpp

@@ -177,7 +177,7 @@ CBlockTemplate* CreateNewBlock(const CScript& _scriptPubKeyIn, int32_t gpucount,
     pblocktemplate->vTxSigOps.push_back(-1); // updated at end
     
     // Largest block you're willing to create:
-    unsigned int nBlockMaxSize = GetArg("-blockmaxsize", DEFAULT_BLOCK_MAX_SIZE);
+    unsigned int nBlockMaxSize = GetArg("-blockmaxsize", MAX_BLOCK_SIZE(chainActive.LastTip()->GetHeight()+1));
     // Limit to betweeen 1K and MAX_BLOCK_SIZE-1K for sanity:
     nBlockMaxSize = std::max((unsigned int)1000, std::min((unsigned int)(MAX_BLOCK_SIZE(chainActive.LastTip()->GetHeight()+1)-1000), nBlockMaxSize));