Hi Bill, I just compiled the new version of cns godunov (v23), but I am still getting the same segmentation fault error as in the previous version (v22). Here is the output of gdb, Program received signal SIGSEGV, Segmentation fault. [Switching to Thread 0x2b658ac0f6f0 (LWP 1430)] 0x00002b658008636c in getp3d_ () from /home/joegi/cfd/overturev23/cgdebug.v23/cns/../cns/lib/libCgcns.so (gdb) where #0 0x00002b658008636c in getp3d_ () from /home/joegi/cfd/overturev23/cgdebug.v23/cns/../cns/lib/libCgcns.so #1 0x00002b65800996e0 in dudr3d_ () from /home/joegi/cfd/overturev23/cgdebug.v23/cns/../cns/lib/libCgcns.so #2 0x00002b657fd23907 in Cgcns::getUt (this=0x18276c0, v=@0x17fd590, gridVelocity_=@0x102e470, dvdt=@0x26c2b70, iparam=0x7fff2b06cf70, rparam=0x7fff2b06cf20, dvdtImplicit=@0x102e470, pmg2=0x1b781b0, pGridVelocity2=0x0) at src/cns.C:1374 #3 0x00002b658056c15b in DomainSolver::getUt (this=0x18276c0, cgf=@0x182b2a8, t=@0x182b2b8, ut=@0x183a008, tForce=0) at src/advance.C:507 #4 0x00002b657fd97c22 in Cgcns::initializeSolution (this=0x18276c0) at src/setupGridFunctions.C:75 #5 0x00002b65805ae7a9 in DomainSolver::setup (this=0x18276c0, time=@0x18272a0) at src/DomainSolver.C:512 #6 0x00002b6580425281 in DomainSolver::setParametersInteractively (this=0x18276c0, runSetupOnExit=true) at src/setup.C:2361 #7 0x000000000042e5f8 in main (argc=2, argv=0x7fff2b081a48) at src/cgcnsMain.C:154 Btw i am compiling overture using gcc, g++ and gfortran v4.2.1 Regards, Joel