gcc/testsuite/gfortran.dg/pr89943_4.f90

! { dg-do compile }
module Foo_mod

   implicit none

   interface
      module function runFoo4C(ndim) bind(C, name="runFoo")
         use, intrinsic :: iso_c_binding
         implicit none
         integer runFoo4c
         integer(c_int32_t) , intent(in) :: ndim
      end function runFoo4C
   end interface

   contains

end module Foo_mod

submodule(Foo_mod) Foo_smod

   contains

      module function runFoo4C(ndim) bind(C, name="runFu")  ! { dg-error "Mismatch in BIND" }
         use, intrinsic :: iso_c_binding     ! { dg-error "Unexpected USE statement in" }
         implicit none                       ! { dg-error "Unexpected IMPLICIT NONE statement" }
         integer(c_int32_t) , intent(in) :: ndim   ! { dg-error "Unexpected data declaration" }
      end function runFoo4C                  ! { dg-error "Expecting END SUBMODULE" }

end submodule Foo_smod