added a missing #include
diff --git a/frc971/control_loops/state_feedback_loop.h b/frc971/control_loops/state_feedback_loop.h
index 7465672..811c875 100644
--- a/frc971/control_loops/state_feedback_loop.h
+++ b/frc971/control_loops/state_feedback_loop.h
@@ -3,6 +3,8 @@
 
 #include <assert.h>
 
+#include <vector>
+
 // Stupid vxworks system headers define it which blows up Eigen...
 #undef m_data