diff --git a/src/cpp/ripple/Application.cpp b/src/cpp/ripple/Application.cpp
index fe84fb5314..031c26136e 100644
--- a/src/cpp/ripple/Application.cpp
+++ b/src/cpp/ripple/Application.cpp
@@ -180,7 +180,8 @@ void Application::setup()
 			options.filter_policy = leveldb::NewBloomFilterPolicy(10);
 		if (theConfig.LDB_IMPORT)
 			options.write_buffer_size = 32 << 20;
-		options.write_buffer_size = std::max(options.write_buffer_size, theConfig.getSize(siLDBWriteSize) << 20);
+		options.write_buffer_size = std::max(options.write_buffer_size,
+			static_cast<size_t>(theConfig.getSize(siLDBWriteSize) << 20));
 		leveldb::Status status = leveldb::DB::Open(options, (theConfig.DATA_DIR / "hashnode").string(), &mHashNodeLDB);
 		if (!status.ok() || !mHashNodeLDB)
 		{