[petsc-users] About KSPConvergedReasonView

[Thibaut Appel]

On 28/08/2020 10:52, Jose E. Roman wrote:
> Thibaut: the changes that Barry mentioned are already in master. Can you try?
>
> Barry: I think the issue is with the PetscViewer argument. KSPView() has a custom Fortran stub that calls PetscPatchDefaultViewers_Fortran(), but this is missing in KSPConvergedReasonView().
>
> Jose

I reconfigured/compiled PETSc from the most recent master branch an hour 
ago; the following compiles fine:

     CALL KSPSolve(ksp,vec_rhs,vec_sol,ierr)
     CHKERRA(ierr)

     CALL KSPGetConvergedReason(ksp,ksp_reason,ierr)
     CHKERRA(ierr)

     CALL KSPConvergedReasonView(ksp,PETSC_VIEWER_STDOUT_WORLD,ierr)
     CHKERRA(ierr)

but I still get a similar backtrace when KSPConvergedReasonView is called:

Program received signal SIGSEGV, Segmentation fault.
0x00007ffff511e89c in PetscObjectTypeCompare (obj=0x8, 
type_name=0x7ffff7580128 "ascii",
     same=0x7fffffffd7c8) at 
/home/thibaut/Packages/petsc/src/sys/objects/destroy.c:160
160      else if (!type_name || !obj->type_name) *same = PETSC_FALSE;
(gdb) backtrace
#0  0x00007ffff511e89c in PetscObjectTypeCompare (obj=0x8, 
type_name=0x7ffff7580128 "ascii",
     same=0x7fffffffd7c8) at 
/home/Packages/petsc/src/sys/objects/destroy.c:160
#1  0x00007ffff66ed4d3 in KSPConvergedReasonView (ksp=0x555555b44860, 
viewer=0x8)
     at /home/Packages/petsc/src/ksp/ksp/interface/itfunc.c:455
#2  0x00007ffff6733fca in kspconvergedreasonview_ (ksp=0x5555559403c0 
<__solver_MOD_ksp>,
     viewer=0x7fffffffda60, __ierr=0x7fffffffda6c)
     at /home/Packages/petsc/src/ksp/ksp/interface/ftn-auto/itfuncf.c:295
#3  0x00005555555e165d in solver::solve_linear_problem (vec_rhs=..., 
vec_sol=...)
     at mod_solver.F90:1867
#4  0x00005555556156fe in solver::solve () at mod_solver.F90:164
#5  0x00005555555bb8f3 in main () at main.F90:67
#6  0x00005555555bb964 in main (argc=1, argv=0x7fffffffe17d) at main.F90:3
#7  0x00007ffff46f71e3 in __libc_start_main () from 
/usr/lib/x86_64-linux-gnu/libc.so.6
#8  0x000055555555cd5e in _start ()

Thibaut

>> El 27 ago 2020, a las 17:59, Barry Smith <bsmith at petsc.dev> escribió:
>>
>>
>>   This is probably due to the final argument being a character string which PETSc has difficulty managing by default for Fortran.
>>
>>   I just removed the format argument from the call so this problem will gone soon.
>>
>>   You could just comment out the call for now and put a print statement in instead.
>>
>>   The problem will be fixed as soon as my merge request gets into master.
>>
>>   Sorry about this.
>>
>>   Barry
>>
>>
>>
>>
>>
>>> On Aug 27, 2020, at 10:25 AM, Thibaut Appel <t.appel17 at imperial.ac.uk> wrote:
>>>
>>> Dear PETSc users,
>>>
>>> I found out that (at least in the master branch) that KSPReasonView has been recently deprecated in favor of KSPConvergedReasonView.
>>>
>>> After changing my application code, I thought I was using the function correctly:
>>>
>>>     CALL KSPGetConvergedReason(ksp,ksp_reason,ierr)
>>>     CHKERRA(ierr)
>>>
>>>     IF (ksp_reason < 0) THEN
>>>
>>>       CALL KSPConvergedReasonView(ksp,PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_DEFAULT,ierr)
>>>       CHKERRA(ierr)
>>>
>>>     END IF
>>>
>>> but I still get the following backtrace
>>>
>>> Program received signal SIGSEGV, Segmentation fault.
>>> 0x00007ffff51dea59 in PetscObjectTypeCompare (obj=0x8,
>>>     type_name=0x7ffff75b5b88 "ascii", same=0x7fffffffd7b8)
>>>     at /home/Packages/petsc/src/sys/objects/destroy.c:160
>>> 160      else if (!type_name || !obj->type_name) *same = PETSC_FALSE;
>>> (gdb) bt
>>> #0  0x00007ffff51dea59 in PetscObjectTypeCompare (obj=0x8,
>>>     type_name=0x7ffff75b5b88 "ascii", same=0x7fffffffd7b8)
>>>     at /home/Packages/petsc/src/sys/objects/destroy.c:160
>>> #1  0x00007ffff6ba1d83 in KSPConvergedReasonView (ksp=0x555555bb2510, viewer=0x8,
>>>     format=PETSC_VIEWER_DEFAULT)
>>>     at /home/Packages/petsc/src/ksp/ksp/interface/itfunc.c:452
>>> #2  0x00007ffff6beb37a in kspconvergedreasonview_ (
>>>     ksp=0x55555593f3c0 <__solver_MOD_ksp>, viewer=0x7fffffffda50,
>>>     format=0x5555558fae48, __ierr=0x7fffffffda6c)
>>>     at /home/Packages/petsc/src/ksp/ksp/interface/ftn-auto/itfuncf.c:295
>>> #3  0x00005555555e040d in solver::solve_linear_problem (vec_rhs=..., vec_sol=...)
>>>     at mod_solver.F90:1872
>>> #4  0x0000555555614453 in solver::solve () at mod_solver.F90:164
>>> #5  0x00005555555ba3c6 in main () at main.F90:67
>>> #6  0x00005555555ba437 in main (argc=1, argv=0x7fffffffe17e) at main.F90:3
>>> #7  0x00007ffff46fa1e3 in __libc_start_main ()
>>>    from /usr/lib/x86_64-linux-gnu/libc.so.6
>>> #8  0x000055555555cd7e in _start ()
>>>
>>> as if there was a type mismatch. Could anyone pinpoint what's wrong?
>>>
>>> Thank you,
>>>
>>> Thibaut
>>>