Merge pull request diffblue#4682 from hannes-steffenhagen-diffblue/fix/xml-output-precondition

Make check in XML output function a precondition

Author: tautschnig

src/goto-analyzer/static_verifier.cpp

@@ -66,7 +66,7 @@ static void static_verifier_xml(
 {
   m.status() << "Writing XML report" << messaget::eom;
 
-  xmlt xml_result;
+  xmlt xml_result{"cprover"};
 
   for(const auto &result : results)
   {

src/util/xml.cpp

@@ -34,8 +34,7 @@ void xmlt::output(std::ostream &out, unsigned indent) const
   // 'name' needs to be set, or we produce mal-formed
   // XML.
 
-  if(name.empty())
-    return;
+  PRECONDITION(!name.empty());
 
   do_indent(out, indent);