tree data BUGFIX path for node with opaque parent
Fixes #1764
diff --git a/src/tree_data.c b/src/tree_data.c
index c9dd7f7..7c89b62 100644
--- a/src/tree_data.c
+++ b/src/tree_data.c
@@ -4041,7 +4041,8 @@
iter_print:
/* print prefix and name */
mod = NULL;
- if (iter->schema && (!iter->parent || (iter->schema->module != iter->parent->schema->module))) {
+ if (iter->schema && (!iter->parent || !iter->parent->schema ||
+ (iter->schema->module != iter->parent->schema->module))) {
mod = iter->schema->module;
}