Robert P. Day removed 8 gazillion occurrences of "extern" on function
definitions.  (That should only be on prototypes.)
diff --git a/archival/libunarchive/seek_by_char.c b/archival/libunarchive/seek_by_char.c
index a50d566..02874db 100644
--- a/archival/libunarchive/seek_by_char.c
+++ b/archival/libunarchive/seek_by_char.c
@@ -24,7 +24,7 @@
  *
  *  TODO: rename to seek_by_read
  */
-extern void seek_by_char(const archive_handle_t *archive_handle, const unsigned int jump_size)
+void seek_by_char(const archive_handle_t *archive_handle, const unsigned int jump_size)
 {
 	if (jump_size) {
 		bb_copyfd_size(archive_handle->src_fd, -1, jump_size);