diff --git a/src/block_cache.h b/src/block_cache.h
index 9fcaf42e7..c79e3d6f0 100644
--- a/src/block_cache.h
+++ b/src/block_cache.h
@@ -150,8 +150,11 @@ public:
 		}
 
 		// Remove old entries until we're under the max size
-		for (auto it = age.rbegin(); size > max_size && it != age.rend(); )
-			KillMacroBlock(**it++);
+		while (size > max_size) {
+			// When size > 0, age should never be empty
+			assert(!age.empty());
+			KillMacroBlock(*age.back());
+		}
 	}
 
 	/// @brief Obtain a data block from the cache