From 05a7aac62e3e0bcf3c206607863d200f52f6588b Mon Sep 17 00:00:00 2001
From: Thomas Krijnen <t.krijnen@gmail.com>
Date: Tue, 28 Mar 2023 15:20:54 +0200
Subject: [PATCH] Prevent double counting elements in single threaded mode

---
 src/ifcgeom/Iterator.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/ifcgeom/Iterator.h b/src/ifcgeom/Iterator.h
index 129be4b7f9..9bcb2826bc 100644
--- a/src/ifcgeom/Iterator.h
+++ b/src/ifcgeom/Iterator.h
@@ -584,7 +584,9 @@ namespace IfcGeom {
 				// Increment the iterator over the list of products using the current
 				// shape representation
 				if (task_result_iterator_ == --all_processed_elements_.end()) {
-					return create();
+					if (!create()) {
+						return nullptr;
+					}
 				}
 				
 				task_result_iterator_++;