Robert P. Day removed 8 gazillion occurrences of "extern" on function
definitions.  (That should only be on prototypes.)
diff --git a/coreutils/mkfifo.c b/coreutils/mkfifo.c
index 77e0e6d..2414be3 100644
--- a/coreutils/mkfifo.c
+++ b/coreutils/mkfifo.c
@@ -29,7 +29,7 @@
 #include "busybox.h"
 #include "libcoreutils/coreutils.h"
 
-extern int mkfifo_main(int argc, char **argv)
+int mkfifo_main(int argc, char **argv)
 {
 	mode_t mode;
 	int retval = EXIT_SUCCESS;