diff --git a/flight/SimPosix/Makefile b/flight/SimPosix/Makefile
index 7244068a0..5253b7262 100644
--- a/flight/SimPosix/Makefile
+++ b/flight/SimPosix/Makefile
@@ -134,6 +134,7 @@ SRC += $(FLIGHTLIB)/fifo_buffer.c
 SRC += $(FLIGHTLIB)/WorldMagModel.c
 SRC += $(FLIGHTLIB)/insgps13state.c
 SRC += $(FLIGHTLIB)/taskmonitor.c
+SRC += $(FLIGHTLIB)/sanitycheck.c
 
 SRC += $(MATHLIB)/sin_lookup.c
 SRC += $(MATHLIB)/pid.c