From 6b431882bc25c72b98eb550c072084f2770dc75b Mon Sep 17 00:00:00 2001
From: Dmitrii Kulikov <164657232+AtheneNoctuaPt@users.noreply.github.com>
Date: Tue, 7 Oct 2025 20:15:37 +0100
Subject: [PATCH] Modeling - Segfault on chamfer or fillet approaching ellipse
 (#738)

Fixed nullptr dereference
---
 src/ModelingAlgorithms/TKFillet/ChFi3d/ChFi3d_Builder_C1.cxx | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/ModelingAlgorithms/TKFillet/ChFi3d/ChFi3d_Builder_C1.cxx b/src/ModelingAlgorithms/TKFillet/ChFi3d/ChFi3d_Builder_C1.cxx
index 73d2af0210..90d1a1ab99 100644
--- a/src/ModelingAlgorithms/TKFillet/ChFi3d/ChFi3d_Builder_C1.cxx
+++ b/src/ModelingAlgorithms/TKFillet/ChFi3d/ChFi3d_Builder_C1.cxx
@@ -2637,6 +2637,10 @@ void ChFi3d_Builder::PerformIntersectionAtEnd(const Standard_Integer Index)
             cfacemoins1->D0(paredge2, pfac2);
             cface->D0(paredge2, pint);
           }
+          else if (C2dint1.IsNull() || C2dint2.IsNull())
+          {
+            throw Standard_ConstructionError("Failed to get p-curve of edge");
+          }
           else
           {
             C2dint1->D0(paredge2, pfac2);
-- 
2.39.5