diff --git a/lib/libc/sys/Makefile.inc b/lib/libc/sys/Makefile.inc
index 5c472f83502..14740b74d6b 100644
--- a/lib/libc/sys/Makefile.inc
+++ b/lib/libc/sys/Makefile.inc
@@ -72,6 +72,7 @@ INTERPOSED = \
 	nanosleep \
 	open \
 	openat \
+	pdfork \
 	poll \
 	ppoll \
 	pselect \