(cp_parser *, tree, tree);
static tree cp_parser_range_for
(cp_parser *, tree, tree, tree);
+static tree cp_parser_perform_range_for_lookup
+ (tree, tree *, tree *);
+static tree cp_parser_range_for_member_function
+ (tree, tree);
static tree cp_parser_jump_statement
(cp_parser *);
static void cp_parser_declaration_statement
}
If RANGE_EXPR is an array:
- BEGIN_EXPR = __range
- END_EXPR = __range + ARRAY_SIZE(__range)
+ BEGIN_EXPR = __range
+ END_EXPR = __range + ARRAY_SIZE(__range)
+ Else if RANGE_EXPR has a member 'begin' or 'end':
+ BEGIN_EXPR = __range.begin()
+ END_EXPR = __range.end()
Else:
BEGIN_EXPR = begin(__range)
END_EXPR = end(__range);
- When calling begin()/end() we must use argument dependent
- lookup, but always considering 'std' as an associated namespace. */
+ If __range has a member 'begin' but not 'end', or vice versa, we must
+ still use the second alternative (it will surely fail, however).
+ When calling begin()/end() in the third alternative we must use
+ argument dependent lookup, but always considering 'std' as an associated
+ namespace. */
tree
cp_convert_range_for (tree statement, tree range_decl, tree range_expr)
else
{
/* Find out the type deduced by the declaration
- * `auto &&__range = range_expr' */
+ `auto &&__range = range_expr'. */
range_type = cp_build_reference_type (make_auto (), true);
range_type = do_auto_deduction (range_type, range_expr,
type_uses_auto (range_type));
- /* Create the __range variable */
+ /* Create the __range variable. */
range_temp = build_decl (input_location, VAR_DECL,
get_identifier ("__for_range"), range_type);
TREE_USED (range_temp) = 1;
LOOKUP_ONLYCONVERTING);
range_temp = convert_from_reference (range_temp);
-
- if (TREE_CODE (TREE_TYPE (range_temp)) == ARRAY_TYPE)
- {
- /* If RANGE_TEMP is an array we will use pointer arithmetic */
- iter_type = build_pointer_type (TREE_TYPE (TREE_TYPE (range_temp)));
- begin_expr = range_temp;
- end_expr
- = build_binary_op (input_location, PLUS_EXPR,
- range_temp,
- array_type_nelts_top (TREE_TYPE (range_temp)),
- 0);
- }
- else
- {
- /* If it is not an array, we must call begin(__range)/end__range() */
- VEC(tree,gc) *vec;
-
- begin_expr = get_identifier ("begin");
- vec = make_tree_vector ();
- VEC_safe_push (tree, gc, vec, range_temp);
- begin_expr = perform_koenig_lookup (begin_expr, vec,
- /*include_std=*/true);
- begin_expr = finish_call_expr (begin_expr, &vec, false, true,
- tf_warning_or_error);
- release_tree_vector (vec);
-
- end_expr = get_identifier ("end");
- vec = make_tree_vector ();
- VEC_safe_push (tree, gc, vec, range_temp);
- end_expr = perform_koenig_lookup (end_expr, vec,
- /*include_std=*/true);
- end_expr = finish_call_expr (end_expr, &vec, false, true,
- tf_warning_or_error);
- release_tree_vector (vec);
-
- /* The unqualified type of the __begin and __end temporaries should
- * be the same as required by the multiple auto declaration */
- iter_type = cv_unqualified (TREE_TYPE (begin_expr));
- if (!same_type_p (iter_type, cv_unqualified (TREE_TYPE (end_expr))))
- error ("inconsistent begin/end types in range-based for: %qT and %qT",
- TREE_TYPE (begin_expr), TREE_TYPE (end_expr));
- }
+ iter_type = cp_parser_perform_range_for_lookup (range_temp,
+ &begin_expr, &end_expr);
}
- /* The new for initialization statement */
+ /* The new for initialization statement. */
begin = build_decl (input_location, VAR_DECL,
get_identifier ("__for_begin"), iter_type);
TREE_USED (begin) = 1;
finish_for_init_stmt (statement);
-/* The new for condition */
+ /* The new for condition. */
condition = build_x_binary_op (NE_EXPR,
begin, ERROR_MARK,
end, ERROR_MARK,
NULL, tf_warning_or_error);
finish_for_cond (condition, statement);
- /* The new increment expression */
+ /* The new increment expression. */
expression = finish_unary_op_expr (PREINCREMENT_EXPR, begin);
finish_for_expr (expression, statement);
- /* The declaration is initialized with *__begin inside the loop body */
+ /* The declaration is initialized with *__begin inside the loop body. */
cp_finish_decl (range_decl,
build_x_indirect_ref (begin, RO_NULL, tf_warning_or_error),
/*is_constant_init*/false, NULL_TREE,
return statement;
}
+/* Solves BEGIN_EXPR and END_EXPR as described in cp_convert_range_for.
+ We need to solve both at the same time because the method used
+ depends on the existence of members begin or end.
+ Returns the type deduced for the iterator expression. */
+
+static tree
+cp_parser_perform_range_for_lookup (tree range, tree *begin, tree *end)
+{
+ if (!COMPLETE_TYPE_P (TREE_TYPE (range)))
+ {
+ error ("range-based %<for%> expression of type %qT "
+ "has incomplete type", TREE_TYPE (range));
+ *begin = *end = error_mark_node;
+ return error_mark_node;
+ }
+ if (TREE_CODE (TREE_TYPE (range)) == ARRAY_TYPE)
+ {
+ /* If RANGE is an array, we will use pointer arithmetic. */
+ *begin = range;
+ *end = build_binary_op (input_location, PLUS_EXPR,
+ range,
+ array_type_nelts_top (TREE_TYPE (range)),
+ 0);
+ return build_pointer_type (TREE_TYPE (TREE_TYPE (range)));
+ }
+ else
+ {
+ /* If it is not an array, we must do a bit of magic. */
+ tree id_begin, id_end;
+ tree member_begin, member_end;
+
+ *begin = *end = error_mark_node;
+
+ id_begin = get_identifier ("begin");
+ id_end = get_identifier ("end");
+ member_begin = lookup_member (TREE_TYPE (range), id_begin,
+ /*protect=*/2, /*want_type=*/false);
+ member_end = lookup_member (TREE_TYPE (range), id_end,
+ /*protect=*/2, /*want_type=*/false);
+
+ if (member_begin != NULL_TREE || member_end != NULL_TREE)
+ {
+ /* Use the member functions. */
+ if (member_begin != NULL_TREE)
+ *begin = cp_parser_range_for_member_function (range, id_begin);
+ else
+ error ("range-based %<for%> expression of type %qT has an "
+ "%<end%> member but not a %<begin%>", TREE_TYPE (range));
+
+ if (member_end != NULL_TREE)
+ *end = cp_parser_range_for_member_function (range, id_end);
+ else
+ error ("range-based %<for%> expression of type %qT has a "
+ "%<begin%> member but not an %<end%>", TREE_TYPE (range));
+ }
+ else
+ {
+ /* Use global functions with ADL. */
+ VEC(tree,gc) *vec;
+ vec = make_tree_vector ();
+
+ VEC_safe_push (tree, gc, vec, range);
+
+ member_begin = perform_koenig_lookup (id_begin, vec,
+ /*include_std=*/true);
+ *begin = finish_call_expr (member_begin, &vec, false, true,
+ tf_warning_or_error);
+ member_end = perform_koenig_lookup (id_end, vec,
+ /*include_std=*/true);
+ *end = finish_call_expr (member_end, &vec, false, true,
+ tf_warning_or_error);
+
+ release_tree_vector (vec);
+ }
+
+ /* Last common checks. */
+ if (*begin == error_mark_node || *end == error_mark_node)
+ {
+ /* If one of the expressions is an error do no more checks. */
+ *begin = *end = error_mark_node;
+ return error_mark_node;
+ }
+ else
+ {
+ tree iter_type = cv_unqualified (TREE_TYPE (*begin));
+ /* The unqualified type of the __begin and __end temporaries should
+ be the same, as required by the multiple auto declaration. */
+ if (!same_type_p (iter_type, cv_unqualified (TREE_TYPE (*end))))
+ error ("inconsistent begin/end types in range-based %<for%> "
+ "statement: %qT and %qT",
+ TREE_TYPE (*begin), TREE_TYPE (*end));
+ return iter_type;
+ }
+ }
+}
+
+/* Helper function for cp_parser_perform_range_for_lookup.
+ Builds a tree for RANGE.IDENTIFIER(). */
+
+static tree
+cp_parser_range_for_member_function (tree range, tree identifier)
+{
+ tree member, res;
+ VEC(tree,gc) *vec;
+
+ member = finish_class_member_access_expr (range, identifier,
+ false, tf_warning_or_error);
+ if (member == error_mark_node)
+ return error_mark_node;
+
+ vec = make_tree_vector ();
+ res = finish_call_expr (member, &vec,
+ /*disallow_virtual=*/false,
+ /*koenig_p=*/false,
+ tf_warning_or_error);
+ release_tree_vector (vec);
+ return res;
+}
/* Parse an iteration-statement.
if (cxx_dialect < cxx0x)
{
error_at (cp_lexer_peek_token (parser->lexer)->location,
- "range-based-for loops are not allowed "
+ "range-based %<for%> loops are not allowed "
"in C++98 mode");
*decl = error_mark_node;
}