[petsc-users] using PETSC_NULL_INTEGER in preallocation routines

[Sanjay Govindjee]

Yes the error is shape mis-match since PETSC_NULL_INTEGER has been 
changed to be an array (whereas it used to just be an integer), and the 
subroutine is expecting an integer not an array.

If 0 is what will always be expected, then I agree, just pass 0. But if 
there is a potential for this to change
in the future, then it seems better to hide this under a named entity.

-sanjay

On 5/14/18 5:52 PM, Smith, Barry F. wrote:
>
>> On May 14, 2018, at 10:45 AM, Sanjay Govindjee <s_g at berkeley.edu> wrote:
>>
>> Barry,
>>    Is it then incorrect (and potentially dangerous) to use PETSC_NULL_INTEGER(1) for these arguments, even if that
>> currently works?
>     I thought you got warnings or errors because you are passing an array instead of a value?
>
>     Anyways since Fortran is pass by reference passing either a PetscInt   II or  PetscInt II(1) does the same things but modern Fortran compilers require you to pass a scalar when expected (II) and an array when expected (II(1)) otherwise the compiler warns or errors. Better to pass what is expected, in this case a 0.
>
>      Barry
>
>> -sanjay
>>
>> On 5/14/18 5:40 PM, Smith, Barry F. wrote:
>>> Chris,
>>>
>>>     These arguments should never have been PETSC_NULL_INTEGER since they are integers (and not pointers or arrays), you should pass 0 for them.
>>>
>>>    Barry
>>>
>>>
>>>> On May 14, 2018, at 4:45 AM, Klaij, Christiaan <C.Klaij at marin.nl> wrote:
>>>>
>>>> With petsc-3.7.5, I had F90 code like this:
>>>>
>>>>   CALL MatSeqAIJSetPreallocation(aa_symmetric,PETSC_NULL_INTEGER,d_nnz,ierr); CHKERRQ(ierr)
>>>>   CALL MatMPIAIJSetPreallocation(aa_symmetric,PETSC_NULL_INTEGER,d_nnz,PETSC_NULL_INTEGER,o_nnz,ierr); CHKERRQ(ierr)
>>>>
>>>> which worked fine. Now, with petsc-3.8.4, the same code gives this compilation error:
>>>>
>>>>   error #6634: The shape matching rules of actual arguments and dummy arguments have been violated.   [PETSC_NULL_INTEGER]
>>>>   CALL MatSeqAIJSetPreallocation(aa_symmetric,PETSC_NULL_INTEGER,d_nnz,ierr); if (ierr .ne. 0) then ; call PetscErrorF(ierr); return; endif
>>>> ----------------------------------------------^
>>>>   error #6634: The shape matching rules of actual arguments and dummy arguments have been violated.   [PETSC_NULL_INTEGER]
>>>>   CALL MatMPIAIJSetPreallocation(aa_symmetric,PETSC_NULL_INTEGER,d_nnz,PETSC_NULL_INTEGER,o_nnz,ierr); if (ierr .ne. 0) then ; call PetscErrorF(ierr); return; endif
>>>> ----------------------------------------------^
>>>>
>>>> What's the intended usage now, simply 0 instead of PETSC_NULL_INTEGER?
>>>>
>>>> Chris
>>>>
>>>>
>>>> dr. ir. Christiaan Klaij  | Senior Researcher | Research & Development
>>>> MARIN | T +31 317 49 33 44 | mailto:C.Klaij at marin.nl | http://www.marin.nl
>>>>
>>>> MARIN news: http://www.marin.nl/web/News/News-items/120-papers-presented-at-NAV2018.htm
>>>>