diff --git a/src/support/lockedpool.cpp b/src/support/lockedpool.cpp
index 2906d30864..ca4248ce63 100644
--- a/src/support/lockedpool.cpp
+++ b/src/support/lockedpool.cpp
@@ -153,7 +153,7 @@ void Arena::walk() const
         printchunk(chunk.first, chunk.second, true);
     std::cout << std::endl;
     for (const auto& chunk: chunks_free)
-        printchunk(chunk.first, chunk.second, false);
+        printchunk(chunk.first, chunk.second->first, false);
     std::cout << std::endl;
 }
 #endif