parse CPP file error with srcML

[jinyao-yu]

pre condition
Gumtree version : https://github.com/GumTreeDiff/gumtree/releases#release-v4.0.0-beta1
srcML : https://www.srcml.org/ （version:Ubuntu 24.04 x86_64）

Issue
I use Gumtree + srcML above to parse CPP file，the error blow occur：
javax.xml.stream.XMLStreamException: ParseError at [row,col]:[2,1]
Message: Premature end of file.
at java.xml/com.sun.org.apache.xerces.internal.impl.XMLStreamReaderImpl.next(XMLStreamReaderImpl.java:652)
at java.xml/com.sun.xml.internal.stream.XMLEventReaderImpl.nextEvent(XMLEventReaderImpl.java:83)
at com.github.gumtreediff.gen.srcml.AbstractSrcmlTreeGenerator.getTreeContext(AbstractSrcmlTreeGenerator.java:79)
at com.github.gumtreediff.gen.srcml.AbstractSrcmlTreeGenerator.generate(AbstractSrcmlTreeGenerator.java:68)
at com.github.gumtreediff.gen.TreeGenerator.generateTree(TreeGenerator.java:41)
at com.github.gumtreediff.gen.TreeGenerator$ReaderConfigurator.reader(TreeGenerator.java:119)
at com.github.gumtreediff.gen.TreeGenerator$ReaderConfigurator.file(TreeGenerator.java:90)
at com.github.gumtreediff.gen.TreeGenerator$ReaderConfigurator.file(TreeGenerator.java:100)
at com.github.gumtreediff.gen.TreeGenerators.getTree(TreeGenerators.java:58)
at com.github.gumtreediff.gen.TreeGenerators.getTree(TreeGenerators.java:70)
at com.github.gumtreediff.client.ParseClient.getTreeContext(ParseClient.java:63)
at com.github.gumtreediff.client.ParseClient.run(ParseClient.java:54)
at com.github.gumtreediff.client.Run.startClient(Run.java:94)
at com.github.gumtreediff.client.Run.main(Run.java:128)
Error while running client 'parse'.
java.lang.NullPointerException: Cannot invoke "com.github.gumtreediff.tree.TreeContext.getRoot()" because "ctx" is null
at com.github.gumtreediff.io.TreeIoUtils.toText(TreeIoUtils.java:152)
at com.github.gumtreediff.client.ParseClient$OutputFormat$6.getSerializer(ParseClient.java:151)
at com.github.gumtreediff.client.ParseClient.run(ParseClient.java:55)
at com.github.gumtreediff.client.Run.startClient(Run.java:94)
at com.github.gumtreediff.client.Run.main(Run.java:128）

by the way，I want to know that when the newest GumTree(version v4.0.0-beta8) bin and lib will release, so that I can use the newest version.