Robert P. Day removed 8 gazillion occurrences of "extern" on function
definitions.  (That should only be on prototypes.)
diff --git a/util-linux/swaponoff.c b/util-linux/swaponoff.c
index c624e74..ce55a13 100644
--- a/util-linux/swaponoff.c
+++ b/util-linux/swaponoff.c
@@ -66,7 +66,7 @@
 
 #define DO_ALL    0x01
 
-extern int swap_on_off_main(int argc, char **argv)
+int swap_on_off_main(int argc, char **argv)
 {
 	int ret;