Index: Makefile
===================================================================
RCS file: /cvsroot/src/lib/libc/Makefile,v
retrieving revision 1.169
diff -u -u -r1.169 Makefile
--- Makefile	15 Jun 2015 14:24:01 -0000	1.169
+++ Makefile	6 Oct 2017 18:51:49 -0000
@@ -19,6 +19,7 @@
 
 .include "Makefile.inc"
 
+LDFLAGS+=	-Wl,--version-script=${.CURDIR}/libc.map
 LIB=		c
 CPPFLAGS+=	-I${.CURDIR}/include -I${.CURDIR}
 
Index: include/namespace.h
===================================================================
RCS file: /cvsroot/src/lib/libc/include/namespace.h,v
retrieving revision 1.186
diff -u -u -r1.186 namespace.h
--- include/namespace.h	8 Feb 2017 17:30:27 -0000	1.186
+++ include/namespace.h	6 Oct 2017 18:51:50 -0000
@@ -32,6 +32,9 @@
 #include <sys/cdefs.h>
 #include <ssp/ssp.h>
 
+#define __libc_deprecated(name) \
+    __asm(".symver _" # name ", " # name "@LIBC12");
+
 #ifndef __lint__
 #define aio_suspend	_aio_suspend
 #define brk		_brk
@@ -264,6 +268,7 @@
 #define endfsent		_endfsent
 #define endgrent		_endgrent
 #define endhostent		_endhostent
+#define endhostent_r		_endhostent_r
 #define endnetconfig		_endnetconfig
 #define endnetent		_endnetent
 #define endnetgrent		_endnetgrent
@@ -345,8 +350,12 @@
 #define getgrouplist		_getgrouplist
 #define getgroupmembership	_getgroupmembership
 #define gethostbyaddr		_gethostbyaddr
+#define gethostbyaddr_r		_gethostbyaddr_r
 #define gethostbyname		_gethostbyname
+#define gethostbyname_r		_gethostbyname_r
+#define gethostbyname2_r	_gethostbyname2_r
 #define gethostent		_gethostent
+#define gethostent_r		_gethostent_r
 #define gethostname		_gethostname
 #define getifaddrs		_getifaddrs
 #define getline			_getline
@@ -592,6 +601,7 @@
 #define setgrent		_setgrent
 #define setgroupent		_setgroupent
 #define sethostent		_sethostent
+#define sethostent_r		_sethostent_r
 #define sethostname		_sethostname
 #define setlogin		_setlogin
 #define setlogmask		_setlogmask
Index: net/gethnamaddr.c
===================================================================
RCS file: /cvsroot/src/lib/libc/net/gethnamaddr.c,v
retrieving revision 1.92
diff -u -u -r1.92 gethnamaddr.c
--- net/gethnamaddr.c	22 Sep 2015 16:16:02 -0000	1.92
+++ net/gethnamaddr.c	6 Oct 2017 18:51:51 -0000
@@ -97,6 +97,10 @@
 
 #include "hostent.h"
 
+__libc_deprecated(gethostbyaddr2_r)
+__libc_deprecated(gethostbyaddr_r)
+__libc_deprecated(gethostbyname_r)
+
 #if defined(_LIBC) && defined(__weak_alias)
 __weak_alias(gethostbyaddr,_gethostbyaddr)
 __weak_alias(gethostbyname,_gethostbyname)
Index: net/sethostent.c
===================================================================
RCS file: /cvsroot/src/lib/libc/net/sethostent.c,v
retrieving revision 1.20
diff -u -u -r1.20 sethostent.c
--- net/sethostent.c	17 Mar 2014 13:24:23 -0000	1.20
+++ net/sethostent.c	6 Oct 2017 18:51:51 -0000
@@ -54,6 +54,9 @@
 
 #include "hostent.h"
 
+__libc_deprecated(sethostent_r)
+__libc_deprecated(endhostent_r)
+
 #ifdef __weak_alias
 __weak_alias(sethostent,_sethostent)
 __weak_alias(endhostent,_endhostent)

--- /dev/null	2017-10-06 14:50:43.547272535 -0400
+++ libc.map	2017-10-06 14:50:30.254872912 -0400
@@ -0,0 +1,9 @@
+
+LIBC12 {
+	global:
+		endhostent_r;
+		sethostent_r;
+		gethostbyname_r;
+		gethostbyname2_r;
+		gethostbyaddr_r;
+};