PR middle-end/27332

[pf3gnuchains/gcc-fork.git] / gcc / tree-loop-linear.c

diff --git a/gcc/tree-loop-linear.c b/gcc/tree-loop-linear.c
index bf353e5..c648ef7 100644 (file)
--- a/gcc/tree-loop-linear.c
+++ b/gcc/tree-loop-linear.c
@@ -178,6 +178,9 @@ try_interchange_loops (lambda_trans_matrix trans,
   unsigned int nb_deps_not_carried_by_i, nb_deps_not_carried_by_j;
   struct data_dependence_relation *ddr;
 
   unsigned int nb_deps_not_carried_by_i, nb_deps_not_carried_by_j;
   struct data_dependence_relation *ddr;
 

+  if (VEC_length (ddr_p, dependence_relations) == 0)
+    return trans;
+

   /* When there is an unknown relation in the dependence_relations, we
      know that it is no worth looking at this loop nest: give up.  */
   ddr = VEC_index (ddr_p, dependence_relations, 0);
   /* When there is an unknown relation in the dependence_relations, we
      know that it is no worth looking at this loop nest: give up.  */
   ddr = VEC_index (ddr_p, dependence_relations, 0);