xmlpatternsvalidator does not allow for non-numeric literals in xsd:double attributes

Attached is an xsd scheme file which seems to be fairly valid, as for Schema 1.0, but is not allowed by xmlpatternsvalidator or QXmlSchema::QXmlSchema, which both say "Error XSDError in file:test.xsd, at line 11, column 70: Value constraint of attribute intInf is not of attributes type: Double content is not listed in the enumeration facet.." If you change 'INF' into '-INF' or 'NAN', the same takes place. If changed to a finite literal (e.g. 28.5), or 'double' changed into 'string', xmlpatternsvalidator (and QXmlSchema constructor) find no errors.