If a complex type is derived by extension and both the base and the dervied type specify an attribute wildcard the {namespace constraint} of the {attribute wildcard} property is the union [1] of the namespace constraints of the two wildcards. It's possible that this union can not be expressed, for instance if the namespace constraints on the two wildcards are ##other and ##local. In such a case we should be reporting an error.


This bug is causing 2 negative JCK test to fail:

xml_schema/msData/wildcards/jaxp/wildZ013.html#wildZ013
xml_schema/msData/wildcards/jaxb/wildZ013.html#wildZ013

It should be noted that the XML Schema 1.0 2nd edition doesn't actually specify this constraint. It's a bug in the spec which is going to be addressed by the working group at some point in the future. See [2] for more information.

[1] http://www.w3.org/TR/2004/REC-xmlschema-1-20041028/#cos-aw-union
[2] http://www.w3.org/Bugs/Public/show_bug.cgi?id=4390