diff --git a/src/modules/mc_pos_control/CMakeLists.txt b/src/modules/mc_pos_control/CMakeLists.txt
index 5d58414732..0de1f49235 100644
--- a/src/modules/mc_pos_control/CMakeLists.txt
+++ b/src/modules/mc_pos_control/CMakeLists.txt
@@ -33,6 +33,7 @@
 px4_add_module(
 	MODULE modules__mc_pos_control
 	MAIN mc_pos_control
+	COMPILE_FLAGS -Os
 	STACK_MAIN 1200
 	SRCS
 		mc_pos_control_main.cpp