isl_merge_divs: handle NULL input

Signed-off-by: Sven Verdoolaege <skimo@kotnet.org>

diff --git a/isl_local_space.c b/isl_local_space.c
index 19ae702..20e4070 100644 (file)
--- a/isl_local_space.c
+++ b/isl_local_space.c
@@ -413,8 +413,12 @@ __isl_give isl_mat *isl_merge_divs(__isl_keep isl_mat *div1,
 {
        int i, j, k;
        isl_mat *div = NULL;
-       unsigned d = div1->n_col - div1->n_row;
+       unsigned d;
 
+       if (!div1 || !div2)
+               return NULL;
+
+       d = div1->n_col - div1->n_row;
        div = isl_mat_alloc(div1->ctx, 1 + div1->n_row + div2->n_row,
                                d + div1->n_row + div2->n_row);
        if (!div)