diff --git a/src/miner.h b/src/miner.h
index 2fab20976..310a0331f 100644
--- a/src/miner.h
+++ b/src/miner.h
@@ -119,6 +119,8 @@ struct update_for_parent_inclusion
     CTxMemPool::txiter iter;
 };
 
+extern CTxMemPool mempool;
+
 /** Generate a new block, without valid proof-of-work */
 class BlockAssembler
 {