[Bug fortran/63744] New: Duplicate use-statement causes error

["roger.ferrer at bsc dot es" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63744

            Bug ID: 63744
           Summary: Duplicate use-statement causes error
           Product: gcc
           Version: 4.9.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: roger.ferrer at bsc dot es

Hi,

(I guess this is related to PR34657)

The following snippet is accepted by gfortran

-- test-ok.f90
MODULE MOO
    INTEGER :: S
END MODULE MOO

SUBROUTINE S1
    USE MOO, ONLY: X => S, X => S

    X = 1
END SUBROUTINE S1
-- end of test-ok.f90

but it is rejected if the program unit SUBROUTINE S1 is renamed to SUBROUTINE
S,
as shown below

-- test.f90
MODULE MOO
    INTEGER :: S
END MODULE MOO

SUBROUTINE S
    USE MOO, ONLY: X => S, X => S

    X = 1
END SUBROUTINE S
-- end of test.f90

$ gfortran -c test.f90
test.f90:6.8:

    USE MOO, ONLY: X => S, X => S
        1
Error: 's' of module 'moo', imported at (1), is also the name of the current
program unit
test.f90:8.5:

    X = 1
     1
Error: Name 'x' at (1) is an ambiguous reference to 's' from module 'moo'

Removing the second rename lets the code be accepted.

  USE MOO, ONLY: X => S

A similar behaviour is observed if we have two repeated USE-statements rather
than two repeated rename's in the rename-list

  USE MOO, ONLY: X => S
  USE MOO, ONLY: X => S

Kind regards,