add -fvisibility=hidden to CC flags, mark XXX_main functions
EXTERNALLY_VISIBLE. 5% size reduction of libbusybox.so

diff --git a/networking/isrv_identd.c b/networking/isrv_identd.c
index 9bc3b60..a93de12 100644
--- a/networking/isrv_identd.c
+++ b/networking/isrv_identd.c
@@ -92,7 +92,7 @@
 	while (do_rd(0, (void*)&buf) == 0);
 }
 
-int fakeidentd_main(int argc, char **argv);
+int fakeidentd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int fakeidentd_main(int argc, char **argv)
 {
 	enum {