diff --git a/cpukit/include/rtems/confdefs/threads.h b/cpukit/include/rtems/confdefs/threads.h
index 12726487ba..33b8c5cee2 100644
--- a/cpukit/include/rtems/confdefs/threads.h
+++ b/cpukit/include/rtems/confdefs/threads.h
@@ -48,9 +48,12 @@
 #include <rtems/confdefs/scheduler.h>
 #include <rtems/confdefs/unlimited.h>
 #include <rtems/score/thread.h>
-#include <rtems/posix/threadsup.h>
 #include <rtems/rtems/tasksdata.h>
 
+#ifdef RTEMS_POSIX_API
+  #include <rtems/posix/threadsup.h>
+#endif
+
 #ifndef CONFIGURE_MAXIMUM_TASKS
   #define CONFIGURE_MAXIMUM_TASKS 0
 #endif