diff --git a/mit-pthreads/include/pthread/ac-types.h b/mit-pthreads/include/pthread/ac-types.h
deleted file mode 100644
index c9dc938f6e8..00000000000
--- a/mit-pthreads/include/pthread/ac-types.h
+++ /dev/null
@@ -1,11 +0,0 @@
-#ifndef pthread_size_t
-#define pthread_ipaddr_type unsigned int
-#define pthread_ipport_type unsigned short
-#define pthread_clock_t long
-#define pthread_size_t unsigned int
-#define pthread_ssize_t int
-#define pthread_time_t long
-#define pthread_fpos_t long long
-#define pthread_off_t long long
-#define pthread_va_list void *
-#endif