[djvictoid]

I have netgen 4.9.13 installed on two machines. On one, a package was
installed from the Ubuntu Software Center on Ubuntu 11.04 (kernel
2.6.39 x86_64), and on the other it was compiled from the latest source
on Red Hat Enterprise Linux Client release 5 (Tikanga) (kernel 2.6.18-
8.el5 x86_64). I used Togl 1.7, tcl 8.4, and tk 8.4. (I had to get sources
for libXmu and libXext as well.) Netgen meshes a complex geometry
perfectly on the ubuntu machine using coarse settings, run in
batchmode. When running on the redhat workstation, however, some
geometries fail inexplicably with a seg fault while tet meshing. Those
geometries can be meshed on the ubuntu install just fine, but they
consistently segfault on the redhat workstation (which has twice the
RAM).

The end of the console messages (returned from my script's log) are:

 
...
Surface 288 / 288
 Optimize Surface

 Meshing subdomain 1 of 283
 Delaunay meshing
 start tetmeshing
netgen -batchmode -coarse -
geofile=arena_job15700_distmembrane.geo -
meshfile=arena_job15700_distmembrane.mesh: Segmentation fault

running gdb and attaching to the running process:

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 46912506037952 (LWP 21785)]
netgen::MeshOptimize3d::SwapImprove (this=<value optimized out>, 
mesh=@0x37130d0, 
    goal=netgen::OPT_REST, working_elements=0x0)
    at ../include/../gprim/geom3d.hpp:89
warning: Source file is more recent than executable.
89	      x[i] = p2(i);
(gdb) list
84	    { x[0] = p2.x[0]; x[1] = p2.x[1]; x[2] = p2.x[2]; }
85	
86	  Point3d (const Point<3> & p2)
87	  {
88	    for (int i = 0; i < 3; i++)
89	      x[i] = p2(i);
90	  }
91	  
92	  ///
93	  Point3d & operator= (const Point3d & p2)
(gdb) backtrace
#0  netgen::MeshOptimize3d::SwapImprove (this=<value optimized out>, 
    mesh=@0x37130d0, goal=netgen::OPT_REST, 
working_elements=0x0)
    at ../include/../gprim/geom3d.hpp:89
#1  0x00000000005d6f1e in netgen::MeshVolume (mp=@0x923280, 
mesh3d=@0x37130d0)
    at meshfunc.cpp:275
#2  0x00000000004b7f23 in netgen::CSGGenerateMesh 
(geom=@0x371a090, 
    mesh=@0x9211c0, perfstepsstart=1, perfstepsend=6, 
    optstr=0x2aaac278b010 " \023\217") at genmesh.cpp:802
#3  0x000000000045b13d in netgen::MeshingDummy () at 
ngpkg.cpp:2151
#4  0x0000000000456bb6 in RunParallel (
    fun=0x45af50 <netgen::MeshingDummy(void*)>, in=0x0) at 
ngpkg.cpp:109
#5  0x00000000004594f2 in netgen::Ng_GenerateMesh 
(clientData=0x0, 
    interp=0x3698ee0, argc=3, argv=0x7fff017f9250) at ngpkg.cpp:2273
#6  0x00002aaaaace4589 in TclInvokeStringCommand () from 
/usr/lib64/libtcl8.4.so
#7  0x00002aaaaace5c73 in TclEvalObjvInternal () from 
/usr/lib64/libtcl8.4.so
#8  0x00002aaaaad0ec21 in Tcl_ExprObj () from /usr/lib64/libtcl8.4.so
#9  0x00002aaaaad1207e in TclCompEvalObj () from 
/usr/lib64/libtcl8.4.so
#10 0x00002aaaaace6b70 in Tcl_EvalObjEx () from 
/usr/lib64/libtcl8.4.so
#11 0x00002aaaaacf1e51 in Tcl_IfObjCmd () from /usr/lib64/libtcl8.4.so
#12 0x00002aaaaace5c73 in TclEvalObjvInternal () from 
/usr/lib64/libtcl8.4.so
#13 0x00002aaaaace616b in Tcl_EvalEx () from /usr/lib64/libtcl8.4.so
#14 0x00002aaaaad29167 in Tcl_FSEvalFile () from 
/usr/lib64/libtcl8.4.so
#15 0x00002aaaaad2924f in Tcl_EvalFile () from /usr/lib64/libtcl8.4.so
#16 0x0000000000454d34 in main (argc=4, argv=<value optimized 
out>)
    at ngappinit.cpp:254

Help!

Finally, the netgen version installed from a package notes that the
OpenCascade geometry kernel is included, whereas my compiled
redhat binary does not. It appears as if OpenCascade libraries are hard
to come by for redhat, but I'm not sure if this is an important difference.

Any ideas? Thanks!

[philippose]

Hello Victor,

A Good Day to you!

Could you please post this message in the forums on the Netgen Sourceforge website?

Since this forum is mainly OpenFOAM Related, you may not get any replies for a matter which is so deep in the Netgen sources.....

The website for the Netgen Mesher is:

http://sourceforge.net/projects/netgen-mesher/


Have a great day ahead!

Philippose