isl_vertices.c: compute_chambers: avoid access to freed data structure

The problem was introduced in 328c78f (isl_tab_from_basic_map: preserve all
constraints in input when tracking, Mon Jan 16 16:55:44 2012 +0100).

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

diff --git a/isl_vertices.c b/isl_vertices.c
index 3cc4026..535bc5f 100644 (file)
--- a/isl_vertices.c
+++ b/isl_vertices.c
@@ -877,10 +877,10 @@ static __isl_give isl_vertices *compute_chambers(__isl_take isl_basic_set *bset,
        bset = isl_basic_set_params(bset);
 
        tab = isl_tab_from_basic_set(bset, 1);
-       isl_basic_set_free(bset);
        for (i = 0; i < bset->n_ineq; ++i)
                if (isl_tab_freeze_constraint(tab, i) < 0)
                        goto error;
+       isl_basic_set_free(bset);
 
        snap = isl_tab_snap(tab);