[PATCH] Don't puke on crfs.ko build if sparse isn't installed

[Alex Chiang]

Hi Zach,

I noticed another build error that can occur if the user does not
have sparse installed.

Here's a patch that alleviates the problem. Note that I'm even
less of an autoconf hacker than I am a filesystem hacker, so feel
free to take the idea and clean it up.

Thanks.

/ac

# HG changeset patch
# User achiang at blender.achiang
# Date 1207019206 21600
# Node ID 51977a8efba4af878601842335f2cfe44aa4021d
# Parent  0a51b6160477801bbc8984b06458d7ee10c74d4b
Allow crfs.ko to build without sparse

We currently pass C=1 on the build line for crfs.ko even if
we might not have sparse installed, which results in build
errors when make can't find sparse.

Let's check for it first.

Signed-off-by: Alex Chiang <achiang at hp.com>

diff -r 0a51b6160477 -r 51977a8efba4 Makefile.in
--- a/Makefile.in	Mon Mar 31 19:21:46 2008 -0600
+++ b/Makefile.in	Mon Mar 31 21:06:46 2008 -0600
@@ -53,7 +53,7 @@ lk/crfs.ko: Makefile lk/Makefile $(wildc
 lk/crfs.ko: Makefile lk/Makefile $(wildcard lk/*.[ch]) lk/wire.h lk/rev.h
 	make -C @LK_DIR@ CONFIG_CRFS_FS=m \
 		EXTRA_CFLAGS="-g -DDEBUG -D__CHECK_ENDIAN__" \
-		C=1 M=$(CURDIR)/lk modules
+		@SPARSE@ M=$(CURDIR)/lk modules
 
 #
 # We try and require that crfs.ko, crfsd, and mount.crfs be from the same
diff -r 0a51b6160477 -r 51977a8efba4 configure.in
--- a/configure.in	Mon Mar 31 19:21:46 2008 -0600
+++ b/configure.in	Mon Mar 31 21:06:46 2008 -0600
@@ -19,6 +19,8 @@ else
 	AC_MSG_RESULT([not found, won't build crfs.ko])
 fi      
 
+AC_CHECK_PROG(SPARSE, sparse, C=1)
+
 AC_SUBST(ALL_TARGETS)
 AC_SUBST(LK_DIR)