isl_basic_set_preimage: add extra sanity check

diff --git a/isl_mat.c b/isl_mat.c
index 04d989c..6f4f889 100644 (file)
--- a/isl_mat.c
+++ b/isl_mat.c
@@ -935,6 +935,7 @@ struct isl_basic_set *isl_basic_set_preimage(struct isl_basic_set *bset,
 
        isl_assert(ctx, bset->dim->nparam == 0, goto error);
        isl_assert(ctx, 1+bset->dim->n_out == mat->n_row, goto error);
+       isl_assert(ctx, mat->n_col > 0, goto error);
 
        if (mat->n_col > mat->n_row)
                bset = isl_basic_set_extend(bset, 0, mat->n_col-1, 0,