[Bug fortran/105847] namelist-object-name can be a renamed host associated entity

["kargl at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105847

kargl at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2022-06-04
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1

--- Comment #1 from kargl at gcc dot gnu.org ---
Found via https://groups.google.com/g/comp.lang.fortran/c/CfODg8wnF8M

The following code should compile and execute to completion.

! { dg-do run }
module m
   integer :: name_in_module = 123
end module

program foo

   use m, name_in_program => name_in_module
   namelist /nl/ name_in_program

   if (name_in_program /= 123) stop 1

   open(unit=10, file='fort.10', status='replace')
   write(10,nl)
   close(10)

   name_in_program = 42
   if (name_in_program /= 42) stop 2

   open(unit=10, file='fort.10', status='old')
   read(10,nl)
   close(10, status='delete')
   if (name_in_program /= 123) stop 3

end 


The following patch fixes the problem.

diff --git a/gcc/fortran/trans-io.cc b/gcc/fortran/trans-io.cc
index 732221f848b..4621ff1c5b7 100644
--- a/gcc/fortran/trans-io.cc
+++ b/gcc/fortran/trans-io.cc
@@ -1666,8 +1666,10 @@ transfer_namelist_element (stmtblock_t * block, const
char * var_name,
   gcc_assert (sym || c);

   /* Build the namelist object name.  */
-
-  string = gfc_build_cstring_const (var_name);
+  if (sym->attr.use_rename)
+    string = gfc_build_cstring_const (sym->ns->use_stmts->rename->local_name);
+  else
+    string = gfc_build_cstring_const (var_name);
   string = gfc_build_addr_expr (pchar_type_node, string);

   /* Build ts, as and data address using symbol or component.  */