[petsc-users] no-debug-mode problem

[Tabrez Ali]

Fortran can be tricky.

Try to run the program in valgrind and/or recheck all your arguments. I 
once forgot MatAssemblyType in the call to MatAssembly and the code 
still ran fine on one machine but failed on other. It is better to test 
with at least 2-3 compilers (GNU, Solaris and Open64 Fortran/C compilers 
are all free on Linux).

T


On 27.06.2013 14:52, Longxiang Chen wrote:
> Dear all,
>
> I use ksp_solver to solve Ax=b, where A is from an outer loop of PDE.
>  Under debug mode(default), it solves the problem in about 4000
> iterations.
> And the final answer is correct (comparing to another solver).
>
> I use intel compiler.
> The program is in Fortran (by mpif90), except the solver is in c (by
> mpicc).
>
> However, when I re-configure with --with-debugging=0 (the only
> change),
> the program terminates in about 30 iterations with the wrong final
> solution.
>
>  Thank you.
>
> Best regards,
> Longxiang Chen
>
> Do something everyday that gets you closer to being done.