[Bug] gmsh with VTK9.x does not work

[FEA-eng]

Is there an existing issue for this?

• I have searched the existing issues

Forums discussion

https://forum.freecadweb.org/viewtopic.php?f=18&t=66948

Version

0.20 (Development)

Full version info

OS: Debian GNU/Linux 11 (bullseye) (X-Cinnamon/lightdm-xsession)
Word size of FreeCAD: 64-bit
Version: 0.20.27972 (Git)
Build type: Release
Branch: master
Hash: 068f02c4b786bc425b44b7f8eec77ea6beab7f61
Python 3.9.2, Qt 5.15.2, Coin 4.0.0, OCC 7.6.1
Locale: English/United States (en_US)

Subproject(s) affected?

FEM

Issue description

gmsh fails to generate a mesh in the case of many distributions (mainly Linux) using VTK9.x
There are several forum threads regarding this issue, links to them can be found in the thread assigned to this report.

Anything else?

No response

Code of Conduct

• I agree to follow this project's Code of Conduct

[akrpic77]

problem seems to be in compactMesh function

FreeCAD/src/3rdParty/salomesmesh/src/SMESHDS/SMESHDS_Mesh.cpp

Line 2153 in 5d49bf7

void SMESHDS_Mesh::compactMesh()

bypassing this function (placing return as first statement in this function) successfully creates the mesh.