class.c (finish_struct_1): Convert integer_zero_node to ssizetype before passing…

class.c (finish_struct_1): Convert integer_zero_node to ssizetype before passing it to set_rtti_entry.

	* class.c (finish_struct_1): Convert integer_zero_node to
 	ssizetype before passing it to set_rtti_entry.
	* typeck2.c (initializer_constant_valid_p): Allow conversion of 0
	of any size to a pointer.

From-SVN: r21438

gcc/cp/ChangeLog

+1998-07-28  Jason Merrill  <jason@yorick.cygnus.com>
+
+	* class.c (finish_struct_1): Convert integer_zero_node to
+ 	ssizetype before passing it to set_rtti_entry.
+	* typeck2.c (initializer_constant_valid_p): Allow conversion of 0
+	of any size to a pointer.
+
 1998-07-27  Mark Mitchell  <mark@markmitchell.com>
 
 	* cp-tree.h (TI_USES_TEMPLATE_PARMS): Remove.

gcc/cp/class.c

@@ -3994,7 +3994,8 @@ finish_struct_1 (t, warn_anon)
 	  /* The first slot is for the rtti offset.  */
 	  pending_virtuals = tree_cons (NULL_TREE, NULL_TREE, pending_virtuals);
 
-	  set_rtti_entry (pending_virtuals, integer_zero_node, t);
+	  set_rtti_entry (pending_virtuals,
+			  convert (ssizetype, integer_zero_node), t);
 	  build_vtable (NULL_TREE, t);
 	}
       else

gcc/cp/typeck2.c

@@ -485,13 +485,18 @@ initializer_constant_valid_p (value, endtype)
 	return initializer_constant_valid_p (TREE_OPERAND (value, 0),
 					     endtype);
 
-      /* Likewise conversions from int to pointers.  */
+      /* Likewise conversions from int to pointers, but also allow
+	 conversions from 0.  */
       if (TREE_CODE (TREE_TYPE (value)) == POINTER_TYPE
-	  && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == INTEGER_TYPE
-	  && (TYPE_PRECISION (TREE_TYPE (value))
-	      <= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
-	return initializer_constant_valid_p (TREE_OPERAND (value, 0),
-					     endtype);
+	  && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == INTEGER_TYPE)
+	{
+	  if (integer_zerop (TREE_OPERAND (value, 0)))
+	    return null_pointer_node;
+	  else if (TYPE_PRECISION (TREE_TYPE (value))
+		   <= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0))))
+	    return initializer_constant_valid_p (TREE_OPERAND (value, 0),
+						 endtype);
+	}
 
       /* Allow conversions to union types if the value inside is okay.  */
       if (TREE_CODE (TREE_TYPE (value)) == UNION_TYPE)