Saxon

Bug reported by Gunther Rademacher:

When showing some more XQuery code to Saxon-EE with byte code

generation, I came across a CannotCompileException. My attempt

to create a minimal reproduction resulted in this:

 declare function local:f($done, $todo)
    {
      if (empty($todo)) then
        $done
      else
        local:f
        (
          (
            $done,
            1 to xs:integer($todo[1]/@n + 1)
          ),
          subsequence($todo, 2)
        )
    };
    local:f
    (
      (),
      (
        <x n="1"/>,
        <y n="2"/>
      )
    )

The stack trace is shown below.

com.saxonica.bytecode.util.CannotCompileException: 
	at com.saxonica.bytecode.converter.DoubleToIntegerCompiler.compileToPrimitive(DoubleToIntegerCompiler.java:49)
	at com.saxonica.bytecode.CastExpressionCompiler.compileToPrimitive(CastExpressionCompiler.java:67)
	at com.saxonica.bytecode.util.CompilerService.compileToPrimitive(CompilerService.java:794)
	at com.saxonica.bytecode.RangeExpressionCompiler.compileToIterator(RangeExpressionCompiler.java:59)
	at com.saxonica.bytecode.util.CompilerService.compileToIterator(CompilerService.java:716)
	at com.saxonica.bytecode.LetExpressionCompiler.compileCommonExpr(LetExpressionCompiler.java:455)
	at com.saxonica.bytecode.UserFunctionCallCompiler.compileFunctionCall(UserFunctionCallCompiler.java:68)
	at com.saxonica.bytecode.UserFunctionCallCompiler.compileToIterator(UserFunctionCallCompiler.java:23)
	at com.saxonica.bytecode.util.CompilerService.compileToIterator(CompilerService.java:716)
	at com.saxonica.bytecode.ChooseCompiler.compileToIterator(ChooseCompiler.java:43)
	at com.saxonica.bytecode.util.CompilerService.compileToIterator(CompilerService.java:716)
	at com.saxonica.bytecode.TailCallLoopCompiler.compileToIterator(TailCallLoopCompiler.java:21)
	at com.saxonica.bytecode.util.CompilerService.compileToIterator(CompilerService.java:716)
	at com.saxonica.bytecode.util.CompilerService.compileToByteCode(CompilerService.java:491)
	at com.saxonica.expr.ee.OptimizerEE.compileToByteCode(OptimizerEE.java:1363)
	at net.sf.saxon.query.XQueryFunction.optimize(XQueryFunction.java:506)
	at net.sf.saxon.query.XQueryFunctionLibrary.optimizeGlobalFunctions(XQueryFunctionLibrary.java:324)
	at net.sf.saxon.query.QueryModule.optimizeGlobalFunctions(QueryModule.java:1123)
	at net.sf.saxon.expr.instruct.Executable.fixupQueryModules(Executable.java:579)
	at net.sf.saxon.query.QueryParser.makeXQueryExpression(QueryParser.java:169)
	at net.sf.saxon.query.StaticQueryContext.compileQuery(StaticQueryContext.java:526)
	at net.sf.saxon.Query.compileQuery(Query.java:702)
	at net.sf.saxon.Query.doQuery(Query.java:332)
	at net.sf.saxon.Query.main(Query.java:107)