Fix github issues/3

diff --git a/cmd/tools/gvpack.c b/cmd/tools/gvpack.c
index 75127bd2e1ad5a6f8cbe1d8d8abd325e176cca40..8864d764e8f1411a24331dec4b430ddb60070891 100644 (file)
--- a/cmd/tools/gvpack.c
+++ b/cmd/tools/gvpack.c
@@ -601,7 +601,7 @@ cloneSubg(Agraph_t * g, Agraph_t * ng, Agsym_t * G_bb, Dt_t * gnames)
        agxset(ng, G_bb, "");   /* Unset all subgraph bb */
 
     /* clone subgraphs */
-    for (subg = agfstsubg (g); subg; subg = agfstsubg (subg)) {
+    for (subg = agfstsubg (g); subg; subg = agnxtsubg (subg)) {
        nsubg = agsubg(ng, xName(gnames, agnameof(subg)), 1);
        agbindrec (nsubg, "Agraphinfo_t", sizeof(Agraphinfo_t), TRUE);
        cloneSubg(subg, nsubg, G_bb, gnames);