[petsc-users] PETSc Fortran 64-bit

[Satish Balay]

On Wed, 1 Feb 2023, Mike Michell wrote:

> @Satish and Blaise - Thank you for the notes.
> 
> @Satish - When you say: "Some routines probably don't have Interface
> definitions - hence compiler can't cat this issue with all functions."

sorry - meant to say 'catch' [not cat]

> Does it mean that I cannot use 64-bit option for those routines, which do
> not have the interface definitions?

All routines are usable. Its just that compiler treats routines
without interface definitions as F77 - and it won't verify the
data-types of arguments passed in. [i.e F77 mode..]

But I do see interface defs for both DMPlexGetDepthStratum() and
DMPlexGetChart() so don't know why they behave differently for you.

src/dm/f90-mod/ftn-auto-interfaces/petscdmplex.h90

>>>>>
      subroutine DMPlexGetDepthStratum(a,b,c,d,z)
       import tDM
       DM a ! DM
       PetscInt b ! PetscInt
       PetscInt c ! PetscInt
       PetscInt d ! PetscInt
       PetscErrorCode z
       end subroutine DMPlexGetDepthStratum

      subroutine DMPlexGetChart(a,b,c,z)
       import tDM
       DM a ! DM
       PetscInt b ! PetscInt
       PetscInt c ! PetscInt
       PetscErrorCode z
       end subroutine DMPlexGetChart

Satish


> Thanks,
> Mike
> 
> 
> > I use the following I all my fortran codes (inspired by a post from
> > Michael Metcalf on comp.lang.fortran many many moons ago):
> >
> > PetscReal,Parameter :: PReal = 1.0
> > Integer,Parameter,Public :: Kr = Selected_Real_Kind(Precision(PReal))
> > PetscInt,Parameter :: PInt = 1
> > Integer,Parameter,Public :: Ki = kind(PInt)
> >
> > You will need to pass constant with their kind (i.e. 1_Ki instead of 1)
> >
> >
> > The advantage of this approach over explicitly trying to figure out the
> > proper type of integer ois that the same code will automatically work with
> > 32 and 64 bit indices.
> >
> > I’ve been wondering if petsc should include these definitions (perhaps
> > under another name).
> >
> > Blaise
> >
> >
> > On Feb 1, 2023, at 2:58 PM, Mike Michell <mi.mike1021 at gmail.com> wrote:
> >
> > Hi all,
> >
> > I want to use PETSc with 64-bit indices with a Fortran90 code. It seems
> > some PETSc functions have no problem, but some of the others do not accept
> > 32-bit error code integer (e.g., "ierr" declared as PetscErrorCode type).
> >
> > For example,
> >
> > call DMPlexGetChart(dm, pst, pend, ierr);CHKERRA(ierr)    works okay,
> >
> > but
> >
> > call DMPlexGetDepthStratum(dm, 0, vst, vend, ierr);CHKERRA(ierr)  gives an
> > error regarding the datatype of ierr. The error basically leads:
> > Error: Type mismatch in argument ‘b’ at (1); passed INTEGER(4) to
> > INTEGER(8)
> >
> > I tried to declare ierr as integer(kind=8) type, but there are still some
> > problems. If PETSc is configured with 32-bit indices, the Fortran code
> > works without problem.
> >
> > What surprising to me is that as mentioned above, DMPlexGetChart() works
> > okay, but  DMPlexGetDepthStratum() does not work with "ierr (PetscErrorCode
> > type)" variable with 64-bit indices.
> >
> > Can I get any comments on it?
> >
> > Thanks,
> > Mike
> >
> >
> > —
> > Canada Research Chair in Mathematical and Computational Aspects of Solid
> > Mechanics (Tier 1)
> > Professor, Department of Mathematics & Statistics
> > Hamilton Hall room 409A, McMaster University
> > 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada
> > https://www.math.mcmaster.ca/bourdin | +1 (905) 525 9140 ext. 27243
> >
> >
>