diff --git a/vlib/os/debugger_darwin.c.v b/vlib/os/debugger_darwin.c.v
index 51f31c8825..ef0318f430 100644
--- a/vlib/os/debugger_darwin.c.v
+++ b/vlib/os/debugger_darwin.c.v
@@ -1,5 +1,6 @@
 module os
 
+#include <sys/types.h>
 #include <sys/ptrace.h>
 
 fn C.ptrace(int, u32, voidptr, int) int