llvm-project/flang/test/Semantics/resolve18.f90

! RUN: %S/test_errors.sh %s %t %f18
module m1
  implicit none
contains
  subroutine foo(x)
    real :: x
  end subroutine
end module

!Note: PGI, Intel, GNU, and NAG allow this; Sun does not
module m2
  use m1
  implicit none
  !ERROR: 'foo' may not be the name of both a generic interface and a procedure unless it is a specific procedure of the generic
  interface foo
    module procedure s
  end interface
contains
  subroutine s(i)
    integer :: i
  end subroutine
end module

subroutine foo
  !ERROR: Cannot use-associate 'foo'; it is already declared in this scope
  use m1
end

subroutine bar
  !ERROR: Cannot use-associate 'bar'; it is already declared in this scope
  use m1, bar => foo
end

!OK to use-associate a type with the same name as a generic
module m3a
  type :: foo
  end type
end
module m3b
  use m3a
  interface foo
  end interface
end

! Can't have derived type and function with same name
module m4a
  type :: foo
  end type
contains
  !ERROR: 'foo' is already declared in this scoping unit
  function foo(x)
  end
end
! Even if there is also a generic interface of that name
module m4b
  type :: foo
  end type
  !ERROR: 'foo' is already declared in this scoping unit
  interface foo
    procedure :: foo
  end interface foo
contains
  function foo(x)
  end
end
module m4c
  type :: foo
  end type
  interface foo
    !ERROR: 'foo' is already declared in this scoping unit
    real function foo()
    end function foo
  end interface foo
end

! Use associating a name that is a generic and a derived type
module m5a
  interface g
  end interface
  type g
  end type
end module
module m5b
  use m5a
  interface g
    procedure f
  end interface
  type(g) :: x
contains
  function f(i)
  end function
end module
subroutine s5
  use m5b
  type(g) :: y
end

module m6
  real :: f6
  interface g6
  !ERROR: Procedure 'f6' was previously declared
    real function f6()
    end function f6
  end interface g6
end module m6

module m7
  integer :: f7
  interface g7
    !ERROR: Procedure 'f7' was previously declared
    real function f7()
    end function f7
  end interface g7
end module m7

module m8
  real :: f8
  interface g8
    !ERROR: Procedure 'f8' was previously declared
    subroutine f8()
    end subroutine f8
  end interface g8
end module m8

module m9
  type f9
  end type f9
  !ERROR: 'f9' is already declared in this scoping unit
  interface f9
    real function f9()
    end function f9
  end interface f9
contains
  function f9(x)
  end function f9
end module m9

module m10
  type :: t10
  end type t10
  interface f10
    function f10()
    end function f10
  end interface f10
contains
  !ERROR: 'f10' is already declared in this scoping unit
  function f10(x)
  end function f10
end module m10

module m11
  type :: t11
  end type t11
  interface i11
    function f11()
    end function f11
  end interface i11
contains
  !ERROR: 'f11' is already declared in this scoping unit
  function f11(x)
  end function f11
end module m11

module m12
  interface f12
    function f12()
    end function f12
  end interface f12
contains
  !ERROR: 'f12' is already declared in this scoping unit
  function f12(x)
  end function f12
end module m12

module m13
  interface f13
    function f13()
    end function f13
  end interface f13
contains
  !ERROR: 'f13' is already declared in this scoping unit
  function f13()
  end function f13
end module m13