X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/c540b8009e2e13d461ecaa7cf17f68950b3539fb..36fa571a13985879dc627c70ecc2340af606aa42:/src/smpi/smpi_group.cpp

diff --git a/src/smpi/smpi_group.cpp b/src/smpi/smpi_group.cpp
index fe817c51d2..41eb2456a1 100644
--- a/src/smpi/smpi_group.cpp
+++ b/src/smpi/smpi_group.cpp
@@ -109,6 +109,8 @@ int smpi_group_index(MPI_Group group, int rank)
 int smpi_group_rank(MPI_Group group, int index)
 {
   int * ptr_rank = nullptr;
+  if (group==MPI_GROUP_EMPTY)
+    return MPI_UNDEFINED;
   char * key = bprintf("%d", index);
   ptr_rank = static_cast<int*>(xbt_dict_get_or_null(group->index_to_rank_map, key));
   xbt_free(key);