[Bug fortran/52270] New: [OOP] Polymorphic vars: wrong intent(in) check, passing nonptr variable to intent(in) ptr dummy

[Bug fortran/52270] New: [OOP] Polymorphic vars: wrong intent(in) check, passing nonptr variable to intent(in) ptr dummy

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52270

             Bug #: 52270
           Summary: [OOP] Polymorphic vars: wrong intent(in) check,
                    passing nonptr variable to intent(in) ptr dummy
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Keywords: rejects-valid
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: burnus@gcc.gnu.org


>From http://j3-fortran.org/doc/meeting/197/12-131.txt

The following program is rejected with:
-----------------------------------------------------
      p%c = 3
      1
Error: Dummy argument 'p' with INTENT(IN) in variable definition context
(assignment) at (1)

    Call s(x)
           1
Error: Actual argument to 'p' at (1) must be polymorphic
-----------------------------------------------------

The first item is bogus as 'p' is a pointer and pointer intents only affect the
pointer association status. Something must go wrong with regards to polymorphic
types.


The second error is formally correct, but the quoted interpretation request by
Malcolm Cohen suggests to make it valid; that would be consistent with the
Fortran 2008 changes regarding "pointer,intent(in)". One could consider to
defer this part until it has passed J3 (or even WG3) voting.


  Program m013
    Type t
      Real c
    End Type
    Type(t),Target :: x
    Call s(x)
    Print *,x%c
  Contains
    Subroutine s(p)
      Class(t),Pointer,Intent(In) :: p
      p%c = 3
    End Subroutine
  End Program

[Bug fortran/52270] [OOP] Polymorphic vars: wrong intent(in) check, passing nonptr variable to intent(in) ptr dummy

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52270

Tobias Burnus <burnus at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |burnus at gcc dot gnu.org

--- Comment #1 from Tobias Burnus <burnus at gcc dot gnu.org> 2012-02-16 09:54:51 UTC ---
Untested patch for both issues.

--- a/gcc/fortran/expr.c
+++ b/gcc/fortran/expr.c
@@ -4650,3 +4650,4 @@ gfc_check_vardef_context (gfc_expr* e, bool pointer, bool
alloc_obj,
   check_intentin = true;
-  ptr_component = sym->attr.pointer;
+  ptr_component = (sym->ts.type == BT_CLASS)
+                 ? CLASS_DATA (sym)->attr.class_pointer : sym->attr.pointer;
   for (ref = e->ref; ref && check_intentin; ref = ref->next)
--- a/gcc/fortran/interface.c
+++ b/gcc/fortran/interface.c
@@ -1708,5 +1708,6 @@ compare_parameter (gfc_symbol *formal, gfc_expr *actual,

-  /* F2008, 12.5.2.5.  */
+  /* F2008, 12.5.2.5; IR F08/0073.  */
   if (formal->ts.type == BT_CLASS
-      && (CLASS_DATA (formal)->attr.class_pointer
+      && ((CLASS_DATA (formal)->attr.class_pointer
+          && !formal->attr.intent == INTENT_IN)
           || CLASS_DATA (formal)->attr.allocatable))

[Bug fortran/52270] [OOP] Polymorphic vars: wrong intent(in) check, passing nonptr variable to intent(in) ptr dummy

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52270

--- Comment #2 from Tobias Burnus <burnus at gcc dot gnu.org> 2012-02-21 13:36:30 UTC ---
Submitted patch, pending review:
  http://gcc.gnu.org/ml/fortran/2012-02/msg00085.html

[Bug fortran/52270] [OOP] Polymorphic vars: wrong intent(in) check, passing nonptr variable to intent(in) ptr dummy

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52270

--- Comment #3 from Tobias Burnus <burnus at gcc dot gnu.org> 2012-03-02 13:07:55 UTC ---
Author: burnus
Date: Fri Mar  2 13:07:46 2012
New Revision: 184784

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=184784
Log:
2012-03-02  Tobias Burnus  <burnus@net-b.de>

        PR fortran/52270
        * expr.c (gfc_check_vardef_context): Fix check for
        intent-in polymorphic pointer .
        * interface.c (compare_parameter): Allow passing TYPE to
        intent-in polymorphic pointer.

2012-03-02  Tobias Burnus  <burnus@net-b.de>

        PR fortran/52270
        * gfortran.dg/class_51.f90: New.


Added:
    trunk/gcc/testsuite/gfortran.dg/class_51.f90
    trunk/gcc/testsuite/gfortran.dg/class_52.f90
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/expr.c
    trunk/gcc/fortran/interface.c
    trunk/gcc/testsuite/ChangeLog

[Bug fortran/52270] [OOP] Polymorphic vars: wrong intent(in) check, passing nonptr variable to intent(in) ptr dummy

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52270

Tobias Burnus <burnus at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |FIXED

--- Comment #4 from Tobias Burnus <burnus at gcc dot gnu.org> 2012-03-02 13:35:13 UTC ---
FIXED on the trunk (i.e. GCC 4.8).