[Bug fortran/94270] New: Bogus unused dummy argument warning/error

[jellby at yahoo dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94270

            Bug ID: 94270
           Summary: Bogus unused dummy argument warning/error
           Product: gcc
           Version: 7.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jellby at yahoo dot com
  Target Milestone: ---

Apparently, passing an external procedure as an argument inside an internal
procedure triggers it:

$ cat test.f90 
subroutine foo()
external bar
call meh(bar)
call foo_internal()
contains
  subroutine foo_internal()
    call meh(bar)
  end subroutine foo_internal
end subroutine foo

$ gfortran -c test.f90 -Wall
test.f90:7:17:

     call meh(bar)
                 1
Warning: Unused dummy argument ‘_formal_0’ at (1) [-Wunused-dummy-argument]

$ gfortran --version
GNU Fortran (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0
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