[patch, fortran] Fix some minor resolution errors in io.c

[Jerry DeLisle]

Hi all,

I plan to commit the following as obvious and simple after regression testing. 
The id tag problem I stumbled on in working on 37498 and Tobias figured it out. 
  The other I noticed from Mikael's post to 35840.  I was already checking for 
more of these little buggers.

Mikael, the problem of not reducing the initialization expression still exists. 
  I do not want to discourage you, so thanks for patch you posted. We really can 
use all the help we can get.  I sincerely hope you will follow up on this.

Best Regards,

Jerry

Index: io.c
===================================================================
--- io.c        (revision 140355)
+++ io.c        (working copy)
@@ -1121,14 +1121,15 @@ match_vtag (const io_tag *tag, gfc_expr

    if (result->symtree->n.sym->attr.intent == INTENT_IN)
      {
-      gfc_error ("Variable tag cannot be INTENT(IN) at %C");
+      gfc_error ("Variable %s cannot be INTENT(IN) at %C", tag->name);
        gfc_free_expr (result);
        return MATCH_ERROR;
      }

    if (gfc_pure (NULL) && gfc_impure_variable (result->symtree->n.sym))
      {
-      gfc_error ("Variable tag cannot be assigned in PURE procedure at %C");
+      gfc_error ("Variable %s cannot be assigned in PURE procedure at %C",
+                tag->name);
        gfc_free_expr (result);
        return MATCH_ERROR;
      }
@@ -1141,13 +1142,13 @@ match_vtag (const io_tag *tag, gfc_expr
  /* Match I/O tags that cause variables to become redefined.  */

  static match
-match_out_tag(const io_tag *tag, gfc_expr **result)
+match_out_tag (const io_tag *tag, gfc_expr **result)
  {
    match m;

-  m = match_vtag(tag, result);
+  m = match_vtag (tag, result);
    if (m == MATCH_YES)
-    gfc_check_do_variable((*result)->symtree);
+    gfc_check_do_variable ((*result)->symtree);

    return m;
  }
@@ -2472,6 +2473,7 @@ gfc_resolve_dt (gfc_dt *dt)
    RESOLVE_TAG (&tag_rec, dt->rec);
    RESOLVE_TAG (&tag_spos, dt->rec);
    RESOLVE_TAG (&tag_advance, dt->advance);
+  RESOLVE_TAG (&tag_id, dt->id);
    RESOLVE_TAG (&tag_iomsg, dt->iomsg);
    RESOLVE_TAG (&tag_iostat, dt->iostat);
    RESOLVE_TAG (&tag_size, dt->size);
@@ -2481,6 +2483,7 @@ gfc_resolve_dt (gfc_dt *dt)
    RESOLVE_TAG (&tag_e_round, dt->round);
    RESOLVE_TAG (&tag_e_blank, dt->blank);
    RESOLVE_TAG (&tag_e_decimal, dt->decimal);
+  RESOLVE_TAG (&tag_e_async, dt->asynchronous);

    e = dt->io_unit;
    if (gfc_resolve_expr (e) == SUCCESS