re PR fortran/78958 (Unallocated memory access after SOURCE-ALLOCATEing…

re PR fortran/78958 (Unallocated memory access after SOURCE-ALLOCATEing unlimited polymorphic object)

gcc/fortran/ChangeLog:

2017-02-05  Andre Vehreschild  <vehre@gcc.gnu.org>

	PR fortran/78958
	* trans-stmt.c (gfc_trans_allocate): Add the multiplying the _len
	component of unlimited polymorphic objects when source-allocating.

From-SVN: r245192

gcc/fortran/ChangeLog

 2017-02-05  Andre Vehreschild  <vehre@gcc.gnu.org>
 
+	PR fortran/78958
+	* trans-stmt.c (gfc_trans_allocate): Add the multiplying the _len
+	component of unlimited polymorphic objects when source-allocating.
+
+2017-02-05  Andre Vehreschild  <vehre@gcc.gnu.org>
+
 	PR fortran/79230
 	* trans-array.c (structure_alloc_comps): Ignore pointer components when
 	freeing structures.

gcc/fortran/trans-stmt.c

@@ -6009,14 +6009,21 @@ gfc_trans_allocate (gfc_code * code)
 	 needs to be provided, which is done most of the time by the
 	 pre-evaluation step.  */
       nelems = NULL_TREE;
-      if (expr3_len && code->expr3->ts.type == BT_CHARACTER)
-	/* When al is an array, then the element size for each element
-	   in the array is needed, which is the product of the len and
-	   esize for char arrays.  */
-	tmp = fold_build2_loc (input_location, MULT_EXPR,
-			       TREE_TYPE (expr3_esize), expr3_esize,
-			       fold_convert (TREE_TYPE (expr3_esize),
-					     expr3_len));
+      if (expr3_len && (code->expr3->ts.type == BT_CHARACTER
+			|| code->expr3->ts.type == BT_CLASS))
+	{
+	  /* When al is an array, then the element size for each element
+	     in the array is needed, which is the product of the len and
+	     esize for char arrays.  For unlimited polymorphics len can be
+	     zero, therefore take the maximum of len and one.  */
+	  tmp = fold_build2_loc (input_location, MAX_EXPR,
+				 TREE_TYPE (expr3_len),
+				 expr3_len, fold_convert (TREE_TYPE (expr3_len),
+							  integer_one_node));
+	  tmp = fold_build2_loc (input_location, MULT_EXPR,
+				 TREE_TYPE (expr3_esize), expr3_esize,
+				 fold_convert (TREE_TYPE (expr3_esize), tmp));
+	}
       else
 	tmp = expr3_esize;
       if (!gfc_array_allocate (&se, expr, stat, errmsg, errlen,