From 29d935d631c522c5e5915d6c0cb9a8af3a1f2390 Mon Sep 17 00:00:00 2001
From: Ben Pfaff <blp@nicira.com>
Date: Fri, 6 May 2011 13:00:49 -0700
Subject: [PATCH] configure: Run sparse automatically if C=1 specified on
 "make" command.

The C=1 convention matches the kernel's convention, so running "make C=1"
will now get sparse results for both userspace and kernel compiles.
---
 acinclude.m4 | 35 +++++++++++++++++++++++++++++++++++
 configure.ac |  1 +
 2 files changed, 36 insertions(+)

diff --git a/acinclude.m4 b/acinclude.m4
index 69e61e0e..3cf793d4 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -347,3 +347,38 @@ AC_DEFUN([OVS_CHECK_XENSERVER_VERSION],
       AC_MSG_ERROR([This appears to be XenServer $ovs_cv_xsversion, but only XenServer 5.6.100 or later is supported.  (If you are really using a supported version of XenServer, you may override this error message by specifying 'ovs_cv_xsversion=5.6.100' on the "configure" command line.)])
       ;;
   esac])
+
+dnl OVS_MAKE_HAS_IF([if-true], [if-false])
+dnl
+dnl Checks whether make has the GNU make $(if condition,then,else) extension.
+dnl Runs 'if-true' if so, 'if-false' otherwise.
+AC_DEFUN([OVS_MAKE_HAS_IF],
+  [AC_CACHE_CHECK(
+     [whether ${MAKE-make} has GNU make \$(if) extension],
+     [ovs_cv_gnu_make_if],
+     [cat <<'EOF' > conftest.mk
+conftest.out:
+	echo $(if x,y,z) > conftest.out
+.PHONY: all
+EOF
+      rm -f conftest.out
+      AS_ECHO(["$as_me:$LINENO: invoking ${MAKE-make} -f conftest.mk all:"]) >&AS_MESSAGE_LOG_FD 2>&1
+      ${MAKE-make} -f conftest.mk conftest.out >&AS_MESSAGE_LOG_FD 2>&1
+      AS_ECHO(["$as_me:$LINENO: conftest.out contains:"]) >&AS_MESSAGE_LOG_FD 2>&1
+      cat conftest.out >&AS_MESSAGE_LOG_FD 2>&1
+      result=`cat conftest.out`
+      rm -f conftest.mk conftest.out
+      if test "X$result" = "Xy"; then
+        ovs_cv_gnu_make_if=yes
+      else
+        ovs_cv_gnu_make_if=no
+      fi])
+   AS_IF([test $ovs_cv_gnu_make_if = yes], [$1], [$2])])
+
+dnl OVS_ENABLE_SPARSE
+AC_DEFUN([OVS_ENABLE_SPARSE],
+  [OVS_MAKE_HAS_IF(
+     [AC_CONFIG_COMMANDS_PRE(
+        [: ${SPARSE=sparse}
+         AC_SUBST([SPARSE])
+         CC='$(if $(C),REAL_CC="'"$CC"'" CHECK="$(SPARSE) -I $(top_srcdir)/include/sparse" cgcc,'"$CC"')'])])])
diff --git a/configure.ac b/configure.ac
index fe91242f..dde42e0c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -86,6 +86,7 @@ OVS_ENABLE_OPTION([-Wno-override-init])
 OVS_CONDITIONAL_CC_OPTION([-Wno-unused], [HAVE_WNO_UNUSED])
 OVS_CONDITIONAL_CC_OPTION([-Wno-unused-parameter], [HAVE_WNO_UNUSED_PARAMETER])
 OVS_ENABLE_WERROR
+OVS_ENABLE_SPARSE
 
 AC_ARG_VAR(KARCH, [Kernel Architecture String])
 AC_SUBST(KARCH)
-- 
2.30.2