Fixed a seg fault in xmlGetQNameProp: a format argument was missing. Fixed * xmlschemas.c include/libxml/schemasInternals.h include/libxml/xmlerror.h: Fixed a seg fault in xmlGetQNameProp: a format argument was missing. Fixed wrong assignment of the owner of a wildcard in xmlSchemaBuildAttributeValidation (in the shorthandform of <complexType>; this caused a seg fault, due to a double-free of the wildcard. Added a check for circular attribute group references. Added a check for circular model group definition references. Fixed a dublicate xmlParserErrors enum value - see bug #151738.