[Bug fortran/44360] wrong-code: host-associated procedure wrongly favoured to use-associated one

["burnus at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #2 from burnus at gcc dot gnu dot org  2010-06-01 12:44 -------
Some debugging shows that at least for
  gfc_match_call
the correct symtree is picked up via gfc_get_ha_sym_tree and saved into
new_st.symtree (tested via: attr.use_assoc == 1 and formal->sym->name == pvec).


However, the search is thrown over in resolve_call:
  if (csym && gfc_current_ns->parent && csym->ns != gfc_current_ns)
      gfc_find_sym_tree (csym->name, gfc_current_ns, 1, &st);
  And this finds the wrong sym.

... Actually, that's incomplete - already c->symtree->n.sym has the wrong
symbol?!?

In case  of functions/variables, it seems to go through check_host_association
- which somehow avoids this problem (cf. below).

 * * *

As the following test case shows, only use-associated SUBROUTINES are
mishandled, use-associated module variables and use-associated FUNCTIONS are
handled correctly:

! { dg-do run }
!
! PR fortran/44360
!
module m
  integer :: var = 43
contains
 integer function fun()
   fun = 42
 end function fun
 subroutine fun2()
   print *, 'OK'
 end subroutine fun2
end module m

module m2
  integer :: var = -2 ! OK, never accessed
contains
 subroutine test()
   use m
   call fun2()                    ! Calls ABORT()
   if (fun() /= 42) call abort()  ! OK
   if (var /= 43) call abort()    ! OK
 end subroutine test
 integer function fun()
   call abort() ! OK, never called
   fun = -3  
 end function fun
 subroutine fun2()
   call abort()  ! <<< Should not be called but is
 end subroutine fun2
end module m2

use m2
call test()
end
! { dg-final { cleanup-modules "m m2" } }


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44360