Mpif90 gfortran strange warning for mpi subroutines: 'Rank mismatch between actual argument...'

[CRquantum]

Thank you very much @MarDie !
Oh, now I see the problem! Thank you very much indeed!
Yeah, uhm, I always think that by using use mpi or include 'mpif.h', all the internal mpi_xxx subroutines should have interface already. OK, I will check with mpi_f08. Cool!
By the way, do you have perhaps some suggestions on my mpi module here,

Why gfortran give my mpi module various warnings while intel fortran just fine

Dear all, I have my mympi.f90 module below. I always use it with Intel Fortran and it works fine and compile with no warning or error. It has been used for some years in nuclear quantum Monte Carlo calculations and on supercomputers (with intel fortran and mpi). However, the thing bothers me a little is that whenever I use mpif90 gfortran and compile it, mpif90 -c mympi.f90 it always give me various warnings mainly type mismatch which I cannot figure out why. Could anyone perhaps have a l…

Thanks again