diff --git a/sys/sys/_types.h b/sys/sys/_types.h
--- a/sys/sys/_types.h
+++ b/sys/sys/_types.h
@@ -67,7 +67,12 @@
 typedef	__uint64_t	__uint_least64_t;
 typedef	__uint64_t	__uintmax_t;
 
-#if __SIZEOF_POINTER__ == 8
+#ifdef __CHERI__
+typedef	__intcap_t	__intptr_t;
+typedef	__intcap_t	__intfptr_t;
+typedef	__uintcap_t	__uintptr_t;
+typedef	__uintcap_t	__uintfptr_t;
+#elif __SIZEOF_POINTER__ == 8
 typedef	__int64_t	__intptr_t;
 typedef	__int64_t	__intfptr_t;
 typedef	__uint64_t	__uintptr_t;