From cd7bdc07b433649f04ef1f72ffa53da4beb1e0c0 Mon Sep 17 00:00:00 2001
From: Sven Verdoolaege <skimo@kotnet.org>
Date: Sat, 26 Jun 2010 10:57:40 +0200
Subject: [PATCH] isl_affine_hull.c: equalities_in_underlying_set: avoid NULL
 pointer dereference

---
 isl_affine_hull.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/isl_affine_hull.c b/isl_affine_hull.c
index 0e8811b..7451fed 100644
--- a/isl_affine_hull.c
+++ b/isl_affine_hull.c
@@ -821,8 +821,11 @@ static struct isl_basic_set *equalities_in_underlying_set(
 		else
 			isl_mat_free(T1);
 		hull = isl_basic_set_preimage(hull, T2);
-		isl_vec_free(hull->sample);
-		hull->sample = sample;
+		if (hull) {
+			isl_vec_free(hull->sample);
+			hull->sample = sample;
+		} else
+			isl_vec_free(sample);
 	}
 
 	return hull;
-- 
2.7.4