isl_basic_map_affine_hull: avoid NULL pointer dereference

diff --git a/isl_affine_hull.c b/isl_affine_hull.c
index 13c818a..df26cf9 100644 (file)
--- a/isl_affine_hull.c
+++ b/isl_affine_hull.c
@@ -919,7 +919,8 @@ struct isl_basic_map *isl_basic_map_affine_hull(struct isl_basic_map *bmap)
 {
        bmap = isl_basic_map_detect_equalities(bmap);
        bmap = isl_basic_map_cow(bmap);
-       isl_basic_map_free_inequality(bmap, bmap->n_ineq);
+       if (bmap)
+               isl_basic_map_free_inequality(bmap, bmap->n_ineq);
        return bmap;
 }