[Gmsh] I have discovered a bug in Gmsh! :o)

[Laurent Klinger]

Hello,

running gmsh on the attached .geo file, with command line "gmsh -3
mesh.geo", yields:


[snip a lot of lines]
Warning : Unable to add point 4317 (will try it later)
Warning : Coplanar points in circum sphere computation
Warning : (1.15701,0,0.180305) (1.1483,0,0.109934) (1.15013,0,0.132817)
(1.15182,0,0.0961568)
Fatal   : Segmentation violation (invalid memory reference)
        : ------------------------------------------------------
        : You have discovered a bug in Gmsh! You may report it
        : by e-mail (together with any helpful data permitting to
        : reproduce it) to <gmsh at geuz.org>
debug!
Abandon


gmsh version is 1.65.0, built with gcc (GCC) 4.1.1 20060724 (prerelease)
(4.1.1-3mdk).

Just to give a quick intro to the geometry, the attached screenshot
shows an overview of the thing. I'm varying the parameter freeze,
which controls the distance between the two points in the red
circle. Here is what happens :
- with freeze = 0.1, 0.2, and cl = 0.02 (characteristic length), no
  problems
- setting freeze to 0.01, two domains out of six are not meshed (but 
  no segfault).
  BTW, the funny thing is, these two domains are the top ones (which
  should be only remotely influenced by the freeze value)
- trying a different value of cl (0.022), just to see if it helps;
  quite the contrary, it makes gmsh segfault.

Hope this helps,

  laurent


-------------- next part --------------
A non-text attachment was scrubbed...
Name: capture.png
Type: image/png
Size: 47652 bytes
Desc: not available
URL: <http://www.geuz.org/pipermail/gmsh/attachments/20070108/9edfc1f6/attachment.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: mesh.geo
Type: text/x-csrc
Size: 5319 bytes
Desc: not available
URL: <http://www.geuz.org/pipermail/gmsh/attachments/20070108/9edfc1f6/attachment.geo>