diff --git a/compiler-rt/test/tsan/debug_alloc_stack.cpp b/compiler-rt/test/tsan/debug_alloc_stack.cpp
index 8fbcf232a1ac..f45caf373524 100644
--- a/compiler-rt/test/tsan/debug_alloc_stack.cpp
+++ b/compiler-rt/test/tsan/debug_alloc_stack.cpp
@@ -6,6 +6,7 @@
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <unistd.h>
 
 #ifndef __APPLE__
 #include <sys/types.h>