Program ISBug
#include "finclude/petscdef.h"
   Use petsc

   Type(IS)                      :: myIS
   PetscInt,Dimension(:),Pointer :: myID
   Integer                       :: rank,n
   PetscErrorCode                :: ierr
   
   Call PetscInitialize(PETSC_NULL_CHARACTER,ierr);CHKERRQ(ierr)
   Call MPI_Comm_rank(PETSC_COMM_WORLD,rank,ierr);CHKERRQ(ierr)
   n = 2*rank

   Call ISCreateStride(PETSC_COMM_WORLD,n,0,1,myIS,ierr);CHKERRQ(ierr)
   Call ISView(myIS,PETSC_VIEWER_STDOUT_WORLD,ierr);CHKERRQ(ierr)
   Call ISGetIndicesF90(myIS,myID,ierr);CHKERRQ(ierr)
   Write(*,*) rank,MyID
   !If (size(myID) > 0) Then
      Call ISRestoreIndicesF90(myIS,myID,ierr);CHKERRQ(ierr)
   !End If
   Call ISDestroy(myIS,ierr);CHKERRQ(ierr)   
   Call PetscFinalize(ierr)
End Program ISBug