Robert P. Day removed 8 gazillion occurrences of "extern" on function
definitions.  (That should only be on prototypes.)
diff --git a/coreutils/mkdir.c b/coreutils/mkdir.c
index e24ef4f..48a95ba 100644
--- a/coreutils/mkdir.c
+++ b/coreutils/mkdir.c
@@ -40,7 +40,7 @@
 	{ 0, 0, 0, 0 }
 };
 
-extern int mkdir_main (int argc, char **argv)
+int mkdir_main (int argc, char **argv)
 {
 	mode_t mode = (mode_t)(-1);
 	int status = EXIT_SUCCESS;