hello ,
I posted my message a few days ago about my codes crash down when using Qudratic Quadrilateral Element(Quad8 and Quad9). Now, I still have this problem.
My codes running well when I use TRI6 elements. Even I use Qudratic Quadrilateral Element on a small mesh, my codes running well. But when the mesh is big (say 20 X20), I got some run time errors, like:

*** glibc detected *** malloc(): memory corruption: 0x10191260 ***

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1074002176 (LWP 6618)]
0x0e4a15cc in _int_malloc () from /lib/tls/libc.so.6

Could anyone give me some help on it? Thank you very much.

Best regards,