l2r bugfixes

git-svn-id: https://ws10smt.googlecode.com/svn/trunk@635 ec762483-ff6d-05da-a07a-a48fb63a330f

1 files changed, 2 insertions, 0 deletions

diff --git a/decoder/viterbi.h b/decoder/viterbi.h
index e78cd157..ac0b9a11 100644
--- a/decoder/viterbi.h
+++ b/decoder/viterbi.h
@@ -55,6 +55,8 @@ typename WeightFunction::Weight Viterbi(const Hypergraph& hg,
       antsb[k] = &vit_result[edgeb.tail_nodes_[k]];
     traverse(edgeb, antsb, cur_node_best_result);
   }
+  if (vit_result.empty())
+    return WeightType(0);
   std::swap(*result, vit_result.back());
   return vit_weight.back();
 }