From b4e1bf8b7ef8704d857a9ee93d40719289b2139e Mon Sep 17 00:00:00 2001
From: Ben Pfaff <blp@nicira.com>
Date: Wed, 25 Jul 2012 10:25:55 -0700
Subject: [PATCH] Makefiles: Enable "dist-hook-git" check only when GNU make is
 in use.

Otherwise, it will always fail because the Makefile in datapath/linux
requires GNU make to generate the list of distributed files.

Signed-off-by: Ben Pfaff <blp@nicira.com>
Reported-by: Ed Maste <emaste@freebsd.org>
---
 Makefile.am  |  8 +++++++-
 acinclude.m4 | 21 +++++++++++++++++++++
 configure.ac |  1 +
 3 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/Makefile.am b/Makefile.am
index 6615fd66e..50c4b1428 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -133,6 +133,11 @@ CLEAN_LOCAL += clean-pycov
 
 # If we're checked out from a Git repository, make sure that every
 # file that is in Git is distributed.
+#
+# We only enable this check when GNU make is in use because the
+# Makefile in datapath/linux, needed to get the list of files to
+# distribute, requires GNU make extensions.
+if GNU_MAKE
 ALL_LOCAL += dist-hook-git
 dist-hook-git: distfiles
 	@if test -e $(srcdir)/.git && (git --version) >/dev/null 2>&1; then \
@@ -148,7 +153,6 @@ dist-hook-git: distfiles
 	    exit 1;							    \
 	  fi;								    \
 	fi
-.PHONY: dist-hook-git
 CLEANFILES += all-distfiles all-gitfiles missing-distfiles
 # The following is based on commands for the Automake "distdir" target.
 distfiles: Makefile
@@ -159,6 +163,8 @@ distfiles: Makefile
 	  sed -e "s|^$$srcdirstrip/||;t" \
 	      -e "s|^$$topsrcdirstrip/|$(top_builddir)/|;t" | sort -u > $@
 CLEANFILES += distfiles
+endif
+.PHONY: dist-hook-git
 
 # Check that "struct vlog_ratelimit" is always declared "static".
 ALL_LOCAL += rate-limit-check
diff --git a/acinclude.m4 b/acinclude.m4
index 8bd4544b5..c332b41a8 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -427,6 +427,27 @@ EOF
         ovs_cv_gnu_make_if=no
       fi])])
 
+dnl OVS_CHECK_GNU_MAKE
+dnl
+dnl Checks whether make is GNU make (because Linux kernel Makefiles
+dnl only work with GNU make).
+AC_DEFUN([OVS_CHECK_GNU_MAKE],
+  [AC_CACHE_CHECK(
+     [whether ${MAKE-make} is GNU make],
+     [ovs_cv_gnu_make],
+     [rm -f conftest.out
+      AS_ECHO(["$as_me:$LINENO: invoking ${MAKE-make} --version:"]) >&AS_MESSAGE_LOG_FD 2>&1
+      ${MAKE-make} --version >conftest.out 2>&1
+      cat conftest.out >&AS_MESSAGE_LOG_FD 2>&1
+      result=`cat conftest.out`
+      rm -f conftest.mk conftest.out
+
+      case $result in # (
+        GNU*) ovs_cv_gnu_make=yes ;; # (
+        *) ovs_cv_gnu_make=no ;;
+      esac])
+   AM_CONDITIONAL([GNU_MAKE], [test $ovs_cv_gnu_make = yes])])
+
 dnl OVS_CHECK_SPARSE_TARGET
 dnl
 dnl The "cgcc" script from "sparse" isn't very good at detecting the
diff --git a/configure.ac b/configure.ac
index 4a89fba41..6006766d7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -69,6 +69,7 @@ OVS_CHECK_LINKER_SECTIONS
 OVS_CHECK_XENSERVER_VERSION
 OVS_CHECK_GROFF
 OVS_CHECK_BRCOMPAT
+OVS_CHECK_GNU_MAKE
 
 OVS_ENABLE_OPTION([-Wall])
 OVS_ENABLE_OPTION([-Wno-sign-compare])
-- 
2.43.0