detecting interface mismatches

[Damian Rouson]

All,

gfortran does not detect mismatches between a function implementation a submodule and the corresponding interface body in the parent module?  See below.  I have not checked the standard for a corresponding constraint to determine whether the compiler is required to catch such a mismatch, but if it’s not required, it would be a great feature to have.  This problem was identified by a student in a course I’m teaching.

Damian

$ cat one.f90 
module one_module
  implicit none
  interface
    module function one()
    end function
  end interface
end module

submodule(one_module) one_submodule
  implicit none
contains
  integer module function one()
    one = 1
  end function
end submodule  

use one_module
print *,one()," is not ",1
end 

$ gfortran one.f90
$ ./a.out
   9.18340949E-41  is not            1

$ gfortran --version
GNU Fortran (MacPorts gcc6 6.1.0_0) 6.1.0


________________________________
Damian Rouson, Ph.D., P.E.
President, Sourcery Institute
http://www.sourceryinstitute.org
+1-510-600-2992 (mobile)