Fix extraData reporting.

libethereum/BlockChain.cpp

@@ -620,6 +620,9 @@ ImportRoute BlockChain::import(VerifiedBlockRef const& _block, OverlayDB const&
 	{
 		ex << errinfo_now(time(0));
 		ex << errinfo_block(_block.block.toBytes());
+		// only populate extraData if we actually managed to extract it. otherwise,
+		// we might be clobbering the existing one.
+		if (!_block.info.extraData().empty())
 			ex << errinfo_extraData(_block.info.extraData());
 		throw;
 	}

libethereum/BlockChain.h

@@ -419,6 +419,9 @@ public:
 			ex << errinfo_phase(1);
 			ex << errinfo_now(time(0));
 			ex << errinfo_block(_block.toBytes());
+			// only populate extraData if we actually managed to extract it. otherwise,
+			// we might be clobbering the existing one.
+			if (!h.extraData().empty())
 				ex << errinfo_extraData(h.extraData());
 			if (_onBad)
 				_onBad(ex);
@@ -441,6 +444,9 @@ public:
 					ex << errinfo_uncleIndex(i);
 					ex << errinfo_now(time(0));
 					ex << errinfo_block(_block.toBytes());
+					// only populate extraData if we actually managed to extract it. otherwise,
+					// we might be clobbering the existing one.
+					if (!h.extraData().empty())
 						ex << errinfo_extraData(h.extraData());
 					if (_onBad)
 						_onBad(ex);
@@ -463,6 +469,9 @@ public:
 					ex << errinfo_transactionIndex(i);
 					ex << errinfo_transaction(d.toBytes());
 					ex << errinfo_block(_block.toBytes());
+					// only populate extraData if we actually managed to extract it. otherwise,
+					// we might be clobbering the existing one.
+					if (!h.extraData().empty())
 						ex << errinfo_extraData(h.extraData());
 					if (_onBad)
 						_onBad(ex);

libethereum/Client.cpp

@@ -219,10 +219,10 @@ void Client::onBadBlock(Exception& _ex) const
 	}
 	if (bytes const* ed = boost::get_error_info<errinfo_extraData>(_ex))
 	{
-		RLP r(*ed);
 		report["hints"]["extraData"] = toHex(*ed);
 		try
 		{
+			RLP r(*ed);
 			if (r[0].toInt<int>() == 0)
 				report["hints"]["minerVersion"] = r[1].toString();
 		}