@cindex @code{flatten} function attribute
@item flatten
Generally, inlining into a function is limited. For a function marked with
-this attribute, every call inside this function is inlined, if possible.
+this attribute, every call inside this function is inlined including the
+calls such inlining introduces to the function (but not recursive calls
+to the function itself), if possible.
Functions declared with attribute @code{noinline} and similar are not
inlined. Whether the function itself is considered for inlining depends
on its size and the current inlining parameters.