diff --git a/mailbox/CMakeLists.txt b/mailbox/CMakeLists.txt
index a3bc60f..0586a46 100644
--- a/mailbox/CMakeLists.txt
+++ b/mailbox/CMakeLists.txt
@@ -38,7 +38,7 @@
 # Build the kernel module
 add_custom_target(mailbox-module ALL
     COMMAND ${CMAKE_MAKE_PROGRAM} -C ${KDIR}
-                  C=2 M=${CMAKE_CURRENT_SOURCE_DIR} CONFIG_ARM_MHU_V2=m CONFIG_ARM_MHU=m
+                  CF=-Wsparse-error C=2 M=${CMAKE_CURRENT_SOURCE_DIR} CONFIG_ARM_MHU_V2=m CONFIG_ARM_MHU=m
                   CROSS_COMPILE=${CROSS_COMPILE} ARCH=${ARCH} modules
                   BYPRODUCTS
                   ${CMAKE_CURRENT_SOURCE_DIR}/arm_mhu.ko