diff --git a/rcl_logging_log4cxx/include/rcl_logging_log4cxx/logging_interface.h b/rcl_logging_log4cxx/include/rcl_logging_log4cxx/logging_interface.h
index 5260114..33b248e 100644
--- a/rcl_logging_log4cxx/include/rcl_logging_log4cxx/logging_interface.h
+++ b/rcl_logging_log4cxx/include/rcl_logging_log4cxx/logging_interface.h
@@ -35,6 +35,7 @@ RCL_LOGGING_PUBLIC
 void rcl_logging_external_log(int severity, const char * name, const char * msg);
 
 RCL_LOGGING_PUBLIC
+RCUTILS_WARN_UNUSED
 rcl_logging_ret_t rcl_logging_external_set_logger_level(const char * name, int level);
 
 
diff --git a/rcl_logging_spdlog/include/rcl_logging_spdlog/logging_interface.h b/rcl_logging_spdlog/include/rcl_logging_spdlog/logging_interface.h
index 2a0bc82..3399b68 100644
--- a/rcl_logging_spdlog/include/rcl_logging_spdlog/logging_interface.h
+++ b/rcl_logging_spdlog/include/rcl_logging_spdlog/logging_interface.h
@@ -35,6 +35,7 @@ RCL_LOGGING_PUBLIC
 void rcl_logging_external_log(int severity, const char * name, const char * msg);
 
 RCL_LOGGING_PUBLIC
+RCUTILS_WARN_UNUSED
 rcl_logging_ret_t rcl_logging_external_set_logger_level(const char * name, int level);