Hi Robert, [I don't see this message to PETSc users in my email so cc'ing manually]
This is odd, something is messed up. These NULL things are certainly 0 and the initial value of these objects is not defined by the compiler, and they could be 0 in some cases. Others are more up on the new Fortran stuff, but I would do a clean build of PETSc (rm -fr arch...), and turn debugging on. You will get a stack trace and it might find something and give a useful error message, or "fix" the problem mysteriously. You could put a print statement in before these are initialized to see what *was* in it that you are clobbering. Mark On Sun, Jul 20, 2025 at 10:33 AM Robert Hager <rha...@pppl.gov> wrote: > FYI > > ---------- Forwarded message --------- > From: Robert Hager <rha...@pppl.gov> > Date: Sun, Jul 20, 2025 at 10:32 AM > Subject: Segfaults when calling some PETSc functions in Fortran with > variables initialized to PETSC_NULL_XX > To: <petsc-users@mcs.anl.gov> > > > Hello, > > I am in the process of updating my code to use PETSc versions >=3.22. (I > am using v3.22.3 compiled with GCC on Perlmutter-CPU at NERSC for debugging > at this time.) After updating all the Fortran function calls that have > changed from v3.21 to v3.22 I am now getting segfaults in some PETSc > routines. In the two instances I was able to identify, the problem seems to > be calling the PETSc function with a PETSc variable that has been > initialized to PETSC_NULL_XX: > > solver%rhs2_mat = PETSC_NULL_MAT > > [...] > > *call* MatDuplicate(solver%Amat,MAT_DO_NOT_COPY_VALUES,solver%rhs2 > _mat,ierr) > > --> Segfault > > > solver%ksp = PETSC_NULL_KSP > > [...] > > *call* KSPCreate(solver%comm,solver%ksp,ierr) > > --> Segfault > > > When I comment out the assignments to PETSC_NULL_XX in the above examples, > the code works just fine. > > Is this the intended behavior or a bug that you might have fixed by now? > > Best, > > Robert >
