Re: Bug 86906 - erroneous name clash with renaming in use statement

[Paul Richard Thomas <paul.richard.thomas@gmail.com>]

Dear All,

This fixes the bug and regtests OK:
Index: /home/pault/svn/trunk/gcc/fortran/resolve.c
===================================================================
*** /home/pault/svn/trunk/gcc/fortran/resolve.c    (revision 262445)
--- /home/pault/svn/trunk/gcc/fortran/resolve.c    (working copy)
*************** resolve_fl_variable_derived (gfc_symbol
*** 12071,12076 ****
--- 12076,12082 ----
       namespace.  14.6.1.3 of the standard and the discussion on
       comp.lang.fortran.  */
    if (sym->ns != sym->ts.u.derived->ns
+       && !sym->ts.u.derived->attr.use_assoc
        && sym->ns->proc_name->attr.if_source != IFSRC_IFBODY)
      {
        gfc_symbol *s;

The gotcha that causes the bug appears in the subsequent line
gfc_find_symbol (sym->ts.u.derived->name, sym->ns, 0, &s);

The symbol for the derived type retains the original name; it is the
symtree that is renamed. Comparing the symbol names is bound to cause
the clash.

I will clear my tree of the work on PR80477 and PR86481 (finalization
stuff) and will commit the fix as obvious.

Cheers

Paul

On Thu, 9 Aug 2018 at 22:36, Damian Rouson <damian@sourceryinstitute.org> wrote:
>
> gfortran 6.4, 7.3, and 8.2 all produce the error message below when
> attempting to use a renamed type in the same scope as the variable that
> motivated the renaming:
>
> $ cat foo.f90
> module foo
>   type config
>   end type
> end module
>   use foo, only: foo_config => config
> contains
>   subroutine cap
>     integer config
>     type(foo_config) extra
>   end subroutine
> end
>
> $ gfortran foo.f90
> foo.f90:9:26:
>
>      integer config
>                   2
>      type(foo_config) extra
>                           1
> Error: The type ‘config’ cannot be host associated at (1) because it is
> blocked by an incompatible object of the same name declared at (2)
>
> $ gfortran --version
> GNU Fortran (GCC) 8.2.0



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