Step-40 fails with "PETSc preconditioner should have anassociated matrix set to be used in solver"

[PRAKARSH PANDEY]

Hi,

I am having issues with using PETSC iterative solvers. I follow the steps in Step40 exactly, and I get: PETSc preconditioner should have an associated matrix set to be used in solver.

I do set the preconditioner correctly, exactly as shown in Step40. I am able to reproduce this error by running step-40 too (shown below). I am using deal.II version 9.0.1, and petsc version 3.10.3 . My question is Step-40 expected to show this error, if not, any pointers on what is causing this error?. 

Thanks,

Pandey

[ 66%] Built target step-40

[100%] Run step-40 with Release configuration

Running with PETSc on 1 MPI rank(s)...

Cycle 0:

   Number of active cells:       1024

   Number of degrees of freedom: 4225

---------------------------------------------------------

TimerOutput objects finalize timed values printed to the

screen by communicating over MPI in their destructors.

Since an exception is currently uncaught, this

synchronization (and subsequent output) will be skipped to

avoid a possible deadlock.

---------------------------------------------------------

ERROR: Uncaught exception in MPI_InitFinalize on proc 0. Skipping MPI_Finalize() to avoid a deadlock.

----------------------------------------------------

Exception on processing: 

--------------------------------------------------------

An error occurred in line <88> of file </scratch/software/dealii/dealii-9.0.1/source/lac/petsc_solver.cc> in function

    void dealii::PETScWrappers::SolverBase::solve(const dealii::PETScWrappers::MatrixBase&, dealii::PETScWrappers::VectorBase&, const dealii::PETScWrappers::VectorBase&, const dealii::PETScWrappers::PreconditionerBase&)

The violated condition was: 

    B != nullptr

Additional information: 

    PETSc preconditioner should have anassociated matrix set to be used in solver.

--------------------------------------------------------

Aborting!

----------------------------------------------------

CMakeFiles/run.dir/build.make:57: recipe for target 'CMakeFiles/run' failed

make[3]: *** [CMakeFiles/run] Error 1

CMakeFiles/Makefile2:131: recipe for target 'CMakeFiles/run.dir/all' failed

make[2]: *** [CMakeFiles/run.dir/all] Error 2

CMakeFiles/Makefile2:138: recipe for target 'CMakeFiles/run.dir/rule' failed

make[1]: *** [CMakeFiles/run.dir/rule] Error 2

Makefile:144: recipe for target 'run' failed

make: *** [run] Error 2

[Daniel Arndt]

Pandey,

 

[...]

--------------------------------------------------------

An error occurred in line <88> of file </scratch/software/dealii/dealii-9.0.1/source/lac/petsc_solver.cc> in function

    void dealii::PETScWrappers::SolverBase::solve(const dealii::PETScWrappers::MatrixBase&, dealii::PETScWrappers::VectorBase&, const dealii::PETScWrappers::VectorBase&, const dealii::PETScWrappers::PreconditionerBase&)

The violated condition was: 

    B != nullptr

Additional information: 

    PETSc preconditioner should have anassociated matrix set to be used in solver.

--------------------------------------------------------

This error message is really unexpected if you are running a non-modified version of step-40. Did you change anything?

It seems that you are running in Release mode. Do you see the same error message in Debug mode as well or would the code stop

to run earlier?

Best,

Daniel

[PRAKARSH PANDEY]

Yeah, I was testing it in release mode. After running in debug mode I realized i didn't have hypre installed. Now it works.

Thanks 

Prakarsh