Try this simple code:

ParseXML("</b>");

This function goes into an endless loop, because at the end of sReadXmlNode() function, the line

p.ReadText(); // skip empty text

doesn't do anything.

My first idea was to change it to

p.Skip();// skip empty text

It seems to be better, but the error message will not be too useful.

My proposed change:

@@ -1005,16 +1005,15 @@ static XmlNode sReadXmlNode(XmlParser& p, ParseXmlFilter *filter, dword style)
 		return m;
 	}
 	if(p.IsText()) {
 		m.CreateText(p.ReadText());
 		m.Shrink();
 		return m;
 	}
-	p.ReadText(); // skip empty text
-	return m;
+	throw XmlError("Unexpected text");
 }
 
 void ParseXmlFilter::EndTag() {}
 
 XmlNode ParseXML(XmlParser& p, dword style, ParseXmlFilter *filter)
 {
 	XmlNode r;

	if(p.ReadText().GetCount() == 0) // skip empty text
		throw XmlError("Unexpected text");