Patchwork [fortran] Fix PR 52668, bogus warning for only list

login
register
mail settings
Submitter Thomas Koenig
Date March 25, 2012, 9:28 a.m.
Message ID <4F6EE534.8070502@netcologne.de>
Download mbox | patch
Permalink /patch/148554/
State New
Headers show

Comments

Thomas Koenig - March 25, 2012, 9:28 a.m.
Hello world,

this fixes a 4.7/4.8 regression with a bogus warning for variables
which were excluded from being imported by "use, only" if they
were in a common block inside the module.

Regression-tested.  OK for trunk and for 4.7 after a few days?

	Thomas

2012-03-25  Thomas Koenig  <tkoenig@gcc.gnu.org>

         PR fortran/52668
         * module.c:  Only mark symbols as use_only if they have been
         imported via an only list.

2012-03-25  Thomas Koenig  <tkoenig@gcc.gnu.org>

         PR fortran/52668
         * gfortran.dg/use_only_6.f90: New test.
! { dg-do compile }
! PR 52668 - there used to be a bogus warning about not using b.
! Original test case by Arnaud Desitter.
module mm
  integer :: a, b
  common /mm1/ a, b
end module mm

subroutine aa()
  use mm, only: a
  implicit none
  a = 1
end subroutine aa
! { dg-final { cleanup-modules "mm" } }

Patch

Index: module.c
===================================================================
--- module.c	(Revision 184854)
+++ module.c	(Arbeitskopie)
@@ -4389,9 +4389,24 @@  load_needed (pointer_info *p)
 
   /* Mark as only or rename for later diagnosis for explicitly imported
      but not used warnings; don't mark internal symbols such as __vtab,
-     __def_init etc.  */
+     __def_init etc. Only mark them if they have been explicitly loaded.  */
+
   if (only_flag && sym->name[0] != '_' && sym->name[1] != '_')
-    sym->attr.use_only = 1;
+    {
+      gfc_use_rename *u;
+
+      /* Search the use/rename list for the variable; if the variable is
+	 found, mark it.  */
+      for (u = gfc_rename_list; u; u = u->next)
+	{
+	  if (strcmp (u->use_name, sym->name) == 0)
+	    {
+	      sym->attr.use_only = 1;
+	      break;
+	    }
+	}
+    }
+
   if (p->u.rsym.renamed)
     sym->attr.use_rename = 1;