From 4551a1ad51ab9bffc309166f83169457f4bfec66 Mon Sep 17 00:00:00 2001
From: howsohazard <143410553+howsohazard@users.noreply.github.com>
Date: Sun, 4 Aug 2024 20:37:51 -0400
Subject: [PATCH] 21135: Fixes possible crash when merging nullptr with a null
 EvaluableNode (#209)

---
 .../evaluablenode/EvaluableNodeTreeManipulation.cpp        | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/Amalgam/evaluablenode/EvaluableNodeTreeManipulation.cpp b/src/Amalgam/evaluablenode/EvaluableNodeTreeManipulation.cpp
index 372cb9b6..ddbdf578 100644
--- a/src/Amalgam/evaluablenode/EvaluableNodeTreeManipulation.cpp
+++ b/src/Amalgam/evaluablenode/EvaluableNodeTreeManipulation.cpp
@@ -412,6 +412,13 @@ EvaluableNode *EvaluableNodeTreeManipulation::CreateGeneralizedNode(NodesMergeMe
 	else if(DoesEvaluableNodeTypeUseStringData(common_type))
 		n->SetStringID(node->GetStringID());
 
+	//if either is a null, then handle logic below by creating a null EvaluableNode
+	EvaluableNode null_merge_node(ENT_NULL);
+	if(n1 == nullptr)
+		n1 = &null_merge_node;
+	if(n2 == nullptr)
+		n2 = &null_merge_node;
+
 	//merge labels
 	size_t n1_num_labels = n1->GetNumLabels();
 	size_t n2_num_labels = n2->GetNumLabels();