diff --git a/lib/libc/Makefile b/lib/libc/Makefile
index f51f1550c28f..033a2ee9d391 100644
--- a/lib/libc/Makefile
+++ b/lib/libc/Makefile
@@ -1,4 +1,4 @@
-#	$NetBSD: Makefile,v 1.149 2012/01/20 16:31:29 joerg Exp $
+#	$NetBSD: Makefile,v 1.150 2013/04/12 19:58:45 joerg Exp $
 #	@(#)Makefile	8.2 (Berkeley) 2/3/94
 #
 # All library objects contain sccsid strings by default; they may be
@@ -42,15 +42,17 @@ assym.h: ${ARCHDIR}/genassym.cf
 .endif
 
 # The following controls how to build compatibility code for old NetBSD
-# binaries. If BUILDCOLD is yes, then we build a separate library; otherwise
+# binaries. If BUILD_LEGACY is yes, then we build a separate library; otherwise
 # we include the code in libc.
-BUILDCOLD?= no
-.if "${BUILDCOLD}" == "yes"
+BUILD_LEGACY?= no
+.if "${BUILD_LEGACY}" == "yes"
 SUBDIR=compat
 .include <bsd.subdir.mk>
 .else
 COMPATDIR=${.CURDIR}/compat
 .include "${.CURDIR}/compat/Makefile.inc"
+# Marker for compat code that can't be easily isolated
+CPPFLAGS+=	-D__BUILD_LEGACY
 .endif
 
 .include "${.CURDIR}/../../common/lib/libc/Makefile.inc"
diff --git a/lib/libc/shlib_version b/lib/libc/shlib_version
index 7183e524b5ae..48625d71d611 100644
--- a/lib/libc/shlib_version
+++ b/lib/libc/shlib_version
@@ -1,7 +1,8 @@
-#	$NetBSD: shlib_version,v 1.237 2013/03/01 18:25:16 joerg Exp $
+#	$NetBSD: shlib_version,v 1.238 2013/04/12 19:58:46 joerg Exp $
 #	Remember to update distrib/sets/lists/base/shl.* when changing
 #
 # things we wish to do on next major version bump:
+# - remove code under BUILD_LEGACY
 # - libc/net/rcmd.c: make __ivaliduser() and __ivaliduser_sa() static
 # - libc/net: resolver update to BIND8/9?
 # - md2, md4, md5, rmd160 & sha1 functions should take the same arguments AFAP