isl_basic_map_align_divs: check divs of src basic map are known before sorting

diff --git a/isl_map.c b/isl_map.c
index 281a92b..3e0b167 100644 (file)
--- a/isl_map.c
+++ b/isl_map.c
@@ -4312,6 +4312,9 @@ struct isl_basic_map *isl_basic_map_align_divs(
        if (src->n_div == 0)
                return dst;
 
+       for (i = 0; i < src->n_div; ++i)
+               isl_assert(src->ctx, !isl_int_is_zero(src->div[i][0]), goto error);
+
        src = order_divs(src);
        dst = isl_basic_map_extend_dim(dst, isl_dim_copy(dst->dim),
                        src->n_div, 0, 2 * src->n_div);