Saxon

Reported here:

https://saxonica.plan.io/boards/3/topics/6411?pn=1

The stylesheet

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"

xmlns:xs="http://www.w3.org/2001/XMLSchema" 

xmlns:math="http://www.w3.org/2005/xpath-functions/math" 

xmlns:map="http://www.w3.org/2005/xpath-functions/map" 

xmlns:mf="http://example.com/mf" 

exclude-result-prefixes="xs math map mf" 

version="3.0">    


<xsl:function name="mf:f1">

    <xsl:sequence select="map { 'value' : 0 }"/>

</xsl:function>


<xsl:template match="/" name="xsl:initial-template">

    <xsl:value-of select="mf:f1()"/>

</xsl:template>

</xsl:stylesheet>

when run with Saxon 9.7.0.5 EE and HE causes a NullPointerException, the complete stack trace is

java.lang.NullPointerException

    at net.sf.saxon.type.TypeHierarchy.relationship(TypeHierarchy.java:298)

    at net.sf.saxon.type.TypeHierarchy.isSubType(TypeHierarchy.java:280)

    at net.sf.saxon.expr.AtomicSequenceConverter.typeCheck(AtomicSequenceConverter.java:152)

    at net.sf.saxon.expr.Operand.typeCheck(Operand.java:185)

    at net.sf.saxon.expr.Expression.typeCheckChildren(Expression.java:428)

    at net.sf.saxon.expr.SystemFunctionCall.typeCheck(SystemFunctionCall.java:82)

    at net.sf.saxon.expr.Operand.typeCheck(Operand.java:185)

    at net.sf.saxon.expr.Expression.typeCheckChildren(Expression.java:428)

    at net.sf.saxon.expr.instruct.SimpleNodeConstructor.typeCheck(SimpleNodeConstructor.java:131)

    at net.sf.saxon.style.XSLTemplate.optimize(XSLTemplate.java:793)

    at net.sf.saxon.style.PrincipalStylesheetModule.optimizeTopLevel(PrincipalStylesheetModule.java:1349)

    at net.sf.saxon.style.PrincipalStylesheetModule.compile(PrincipalStylesheetModule.java:1199)

    at net.sf.saxon.style.Compilation.compilePackage(Compilation.java:245)

    at net.sf.saxon.style.StylesheetModule.loadStylesheet(StylesheetModule.java:260)

    at net.sf.saxon.style.Compilation.compileSingletonPackage(Compilation.java:101)

    at net.sf.saxon.s9api.XsltCompiler.compile(XsltCompiler.java:839)

    at net.sf.saxon.Transform.doTransform(Transform.java:727)

    at net.sf.saxon.Transform.main(Transform.java:77)