Merge commit 'cf734784b0433dfa6b77909f83cc3620e523f5d7'
diff --git a/libosmocore/src/rate_ctr.c b/libosmocore/src/rate_ctr.c
index 9b2459e..e48c779 100644
--- a/libosmocore/src/rate_ctr.c
+++ b/libosmocore/src/rate_ctr.c
@@ -51,9 +51,7 @@
 		return NULL;
 
 	group->desc = desc;
-	/* Generate the Group prefix from the user-specified index */
-	group->name_prefix = talloc_size(group, strlen(desc->group_prefix_fmt) + 20);
-	sprintf(group->name_prefix, desc->group_prefix_fmt, idx);
+	group->idx = idx;
 
 	llist_add(&group->list, &rate_ctr_groups);