From 8cb4518f339339736a7f408dad20244c5677d03f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Stefan=20Br=C3=BCns?= <stefan.bruens@rwth-aachen.de>
Date: Fri, 20 Dec 2024 14:29:28 +0100
Subject: [PATCH] Fix invalid string access in BoundaryLayerTool

When AddFaceDescriptor reallocates the array the fd reference becomes
dangling.

See #203
---
 libsrc/meshing/boundarylayer.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/libsrc/meshing/boundarylayer.cpp b/libsrc/meshing/boundarylayer.cpp
index 3eaaa508..c472f919 100644
--- a/libsrc/meshing/boundarylayer.cpp
+++ b/libsrc/meshing/boundarylayer.cpp
@@ -723,7 +723,8 @@ namespace netgen
             new_fd.SetBCProperty(new_si);
             mesh.AddFaceDescriptor(new_fd);
             si_map[facei] = new_si;
-            mesh.SetBCName(new_si-1, fd.GetBCName());
+            // AddFaceDescriptor may reallocate, fd is invalidated
+            mesh.SetBCName(new_si-1, mesh.GetFaceDescriptor(facei).GetBCName());
             face_done.SetBit(facei);
           }
       }