[Bug fortran/33541] gfortran wrongly imports renamed-use-associated symbol unrenamed

[pault at gcc dot gnu dot org]

------- Comment #3 from pault at gcc dot gnu dot org  2007-11-15 09:46 -------
The patch below fixes the reported bug.  I am going to check to see what needs
to be done to extend this to generic interfaces and operators.

Paul

Index: gcc/fortran/module.c
===================================================================
*** gcc/fortran/module.c        (révision 130174)
--- gcc/fortran/module.c        (copie de travail)
*************** find_symtree_for_symbol (gfc_symtree *st
*** 3492,3497 ****
--- 3492,3522 ----
  }


+ /* A recursive function to look for a spefici symbol by name and by
+    module.  Whilst several symtrees might point to one symbol, its
+    is sufficient for the purposes here than one exist.  */
+ static gfc_symtree *
+ find_symbol (gfc_symtree *st, const char *name, const char *module)
+ {
+   int c;
+   gfc_symtree *retval;
+
+   if (st == NULL || st->n.sym == NULL)
+     return NULL;
+
+   c = strcmp (name, st->n.sym->name);
+   if (c == 0 && strcmp (module, st->n.sym->module) == 0)
+     return st;
+
+   retval = find_symbol (st->left, name, module);
+
+   if (retval == NULL)
+     retval = find_symbol (st->right, name, module);
+
+   return retval;
+ }
+
+
  /* Read a module file.  */

  static void
*************** read_module (void)
*** 3616,3621 ****
--- 3641,3655 ----
              continue;
            }

+         /* If a symbol of the same name and module exists already,
+            this symbol, which is not in an ONLY clause, must not be
+            added to the namespace(11.3.2).  Note that find_symbol
+            only returns the first occurrence that it finds.  */
+         if (p == name && strcmp (name, module_name) != 0
+               && find_symbol (gfc_current_ns->sym_root, name,
+                               module_name))
+           continue;
+
          st = gfc_find_symtree (gfc_current_ns->sym_root, p);

          if (st != NULL)
*************** read_module (void)
*** 3627,3632 ****
--- 3661,3674 ----
            }
          else
            {
+             st = gfc_find_symtree (gfc_current_ns->sym_root, name);
+
+             /* Make symtree inaccessible by renaming if the symbol has
+                been added by a USE statement without an ONLY(11.3.2).  */
+             if (st && st->name == st->n.sym->name
+                    && strcmp (st->n.sym->module, module_name) == 0)
+               st->name = gfc_get_string ("hidden.%s", name);
+
              /* Create a symtree node in the current namespace for this
                 symbol.  */
              st = check_unique_name (p)
Index: gcc/testsuite/gfortran.dg/use_only_1.f90
===================================================================
*** gcc/testsuite/gfortran.dg/use_only_1.f90    (révision 0)
--- gcc/testsuite/gfortran.dg/use_only_1.f90    (révision 0)
***************
*** 0 ****
--- 1,31 ----
+ ! { dg-do run }
+ ! { dg-options "-O1" }
+ ! Checks the fix for PR33541, in which a requirement
+ ! of F95 11.3.2 was not being met: The local names
+ ! 'x' and 'y' coming from the USE statements without
+ ! an ONLY clause should not survive in the presence
+ ! of the locally renamed versions.
+ !
+ ! Reported by Reported by John Harper in
+ ! http://gcc.gnu.org/ml/fortran/2007-09/msg00397.html
+ !
+ MODULE xmod
+   integer(4) :: x = -666
+ END MODULE xmod
+
+ MODULE ymod
+   integer(4) :: y = -666
+ END MODULE ymod
+
+ PROGRAM test2uses
+   USE xmod
+   USE xmod, ONLY: xrenamed => x
+   USE ymod, ONLY: yrenamed => y
+   USE ymod
+   implicit integer(2) (a-z)
+   x = 666  ! These assignments should generate implicitly typed
+   y = 666  ! local variable 'x' and 'y'.
+   if (kind(xrenamed) == kind(x)) call abort ()
+   if (kind(yrenamed) == kind(y)) call abort ()
+ END PROGRAM test2uses
+ ! { dg-final { cleanup-modules "xmod ymod" } }


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33541