diff --git a/sago/platform_folders.cpp b/sago/platform_folders.cpp
index 1531e91..f4a1cd1 100644
--- a/sago/platform_folders.cpp
+++ b/sago/platform_folders.cpp
@@ -103,8 +103,7 @@ std::string win32_utf16_to_utf8(const wchar_t* wstr) {
 	}
 	if (actualSize == 0) {
 		// WideCharToMultiByte return 0 for errors.
-		const std::string errorMsg = "UTF16 to UTF8 failed with error code: " + GetLastError();
-		throw std::runtime_error(errorMsg.c_str());
+		throw std::runtime_error("UTF16 to UTF8 failed with error code: " + std::to_string(GetLastError()));
 	}
 	return res;
 }