re PR fortran/66679 ([OOP] ICE with class(*) and transfer)

2018-08-12  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/66679
	* trans-intrinsic.c (gfc_conv_intrinsic_transfer): Class array
	elements are returned as references to the data element. Get
	the class expression by stripping back the references. Use this
	for the element size.

2018-08-12  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/66679
	* gfortran.dg/transfer_class_3.f90: New test.

From-SVN: r263499

gcc/fortran/ChangeLog

 2018-08-12  Paul Thomas  <pault@gcc.gnu.org>
 
+	PR fortran/66679
+	* trans-intrinsic.c (gfc_conv_intrinsic_transfer): Class array
+	elements are returned as references to the data element. Get
+	the class expression by stripping back the references. Use this
+	for the element size.
+
+2018-08-12  Paul Thomas  <pault@gcc.gnu.org>
+
 	PR fortran/86906
 	* resolve.c (resolve_fl_variable_derived): Check if the derived
 	type is use associated before checking for the host association

gcc/fortran/trans-intrinsic.c

@@ -7369,13 +7369,14 @@ gfc_conv_intrinsic_transfer (gfc_se * se, gfc_expr * expr)
   tree upper;
   tree lower;
   tree stmt;
+  tree class_ref = NULL_TREE;
   gfc_actual_arglist *arg;
   gfc_se argse;
   gfc_array_info *info;
   stmtblock_t block;
   int n;
   bool scalar_mold;
-  gfc_expr *source_expr, *mold_expr;
+  gfc_expr *source_expr, *mold_expr, *class_expr;
 
   info = NULL;
   if (se->loop)
@@ -7406,7 +7407,24 @@ gfc_conv_intrinsic_transfer (gfc_se * se, gfc_expr * expr)
     {
       gfc_conv_expr_reference (&argse, arg->expr);
       if (arg->expr->ts.type == BT_CLASS)
-	source = gfc_class_data_get (argse.expr);
+	{
+	  tmp = build_fold_indirect_ref_loc (input_location, argse.expr);
+	  if (GFC_CLASS_TYPE_P (TREE_TYPE (tmp)))
+	    source = gfc_class_data_get (tmp);
+	  else
+	    {
+	      /* Array elements are evaluated as a reference to the data.
+		 To obtain the vptr for the element size, the argument
+		 expression must be stripped to the class reference and
+		 re-evaluated. The pre and post blocks are not needed.  */
+	      gcc_assert (arg->expr->expr_type == EXPR_VARIABLE);
+	      source = argse.expr;
+	      class_expr = gfc_find_and_cut_at_last_class_ref (arg->expr);
+	      gfc_init_se (&argse, NULL);
+	      gfc_conv_expr (&argse, class_expr);
+	      class_ref = argse.expr;
+	    }
+	}
       else
 	source = argse.expr;
 
@@ -7418,6 +7436,9 @@ gfc_conv_intrinsic_transfer (gfc_se * se, gfc_expr * expr)
 					 argse.string_length);
 	  break;
 	case BT_CLASS:
+	  if (class_ref != NULL_TREE)
+	    tmp = gfc_class_vtab_size_get (class_ref);
+	  else
 	    tmp = gfc_class_vtab_size_get (argse.expr);
 	  break;
 	default:

gcc/testsuite/ChangeLog

 2018-08-12  Paul Thomas  <pault@gcc.gnu.org>
 
+	PR fortran/66679
+	* gfortran.dg/transfer_class_3.f90: New test.
+
+2018-08-12  Paul Thomas  <pault@gcc.gnu.org>
+
 	PR fortran/86906
 	* gfortran.dg/use_rename_9.f90: New test.
 

gcc/testsuite/gfortran.dg/transfer_class_3.f90

+! { dg-do run }
+!
+! Test the fix for PR66679.
+!
+! Contributed by Miha Polajnar  <polajnar.miha@gmail.com>
+!
+program main
+  implicit none
+  class(*), allocatable :: vec(:)
+  integer :: var, ans(2)
+  allocate(vec(2),source=[1_4, 2_4])
+
+! This worked correctly.
+  if (any (transfer(vec,[var],2) .ne. [1_4, 2_4])) stop 1
+
+! This caused an ICE.
+  if (any ([transfer(vec(1),[var]), transfer(vec(2),[var])] .ne. [1_4, 2_4])) stop 2
+end program main