[src/trunk]: src/usr.bin/config config(1): Fix build of old tree (bin/49389)

[uebayasi <uebayasi%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/402f0e41785f
branches:  trunk
changeset: 805062:402f0e41785f
user:      uebayasi <uebayasi%NetBSD.org@localhost>
date:      Mon Dec 15 10:10:24 2014 +0000

description:
config(1): Fix build of old tree (bin/49389)

Define the default, empty "build_kernel" target, so that old source trees,
whose sys/conf/Makefile.kern.inc don't have "build_kernel" .USE target, can
be built.

(When "build_kernel" is defined, the target is overriden, as far as
sys/conf/Makefile.kern.inc is included later than the "netbsd: ..." definition
in sys/arch/*/conf/Makefile.*.)

This should address PR bin/49389.

diffstat:

 usr.bin/config/mkmakefile.c |  5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)

diffs (26 lines):

diff -r 9dcef377dc75 -r 402f0e41785f usr.bin/config/mkmakefile.c
--- a/usr.bin/config/mkmakefile.c       Mon Dec 15 08:17:15 2014 +0000
+++ b/usr.bin/config/mkmakefile.c       Mon Dec 15 10:10:24 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: mkmakefile.c,v 1.34 2014/11/21 20:46:56 christos Exp $ */
+/*     $NetBSD: mkmakefile.c,v 1.35 2014/12/15 10:10:24 uebayasi Exp $ */
 
 /*
  * Copyright (c) 1992, 1993
@@ -45,7 +45,7 @@
 #endif
 
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: mkmakefile.c,v 1.34 2014/11/21 20:46:56 christos Exp $");
+__RCSID("$NetBSD: mkmakefile.c,v 1.35 2014/12/15 10:10:24 uebayasi Exp $");
 
 #include <sys/param.h>
 #include <ctype.h>
@@ -581,6 +581,7 @@
        fputs("\n\n", fp);
        TAILQ_FOREACH(cf, &allcf, cf_next) {
                fprintf(fp, "KERNELS+=%s\n", cf->cf_name);
+               fprintf(fp, "build_kernel:\n");
                fprintf(fp, "%s: ${SYSTEM_DEP} swap%s.o vers.o build_kernel\n",
                    cf->cf_name, cf->cf_name);
                fprintf(fp, "swap%s.o: swap%s.c\n"