Bug in SparqlExpressionGenerators.h

[IoannisNezis]

I managed to produce this error:

Assertion it != varToColMap.end() failed. Please report this to the developers. In file "/qlever/src/engine/sparqlExpressions/SparqlExpressionGenerators.h " at line 40

With this query:

#values completion sensitive
PREFIX wd: <http://www.wikidata.org/entity/>
PREFIX wdt: <http://www.wikidata.org/prop/direct/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>
SELECT ?qlue_ls_entity (SAMPLE(?name) AS ?qlue_ls_label) (SAMPLE(?count) AS ?qlue_ls_count) WHERE {
  {
    SELECT ?qlue_ls_entity (COUNT(?qlue_ls_entity) AS ?count) WHERE {
      {
        ?driver wdt:P106 wd:Q10841764
                BIND (?driver as ?qlue_ls_entity)

      }
    }
    GROUP BY ?qlue_ls_entity
  }
 
  BIND (COALESCE(?optional_alias, ?qlue_ls_entity) AS ?alias)
  FILTER (REGEX(STR(?name),"^Max") || REGEX(STR(?alias),"^Max"))
}
GROUP BY ?qlue_ls_entity
ORDER BY DESC(?qlue_ls_count)
LIMIT 101
OFFSET 0

[RobinTF]

@IoannisNezis I reduced the query to this:

SELECT * {
  FILTER (REGEX(?name,"^"))
}

still results in the same error. The PrefixRegexExpression doesn't delegate to the VariableExpression which always handles an unbound variable properly, so this handling is simply missing.

[IoannisNezis]

Im always annoyed when people send me non mimimized input and not im the Culprit xD
(I was doing some task and just wanted to dump this quickly, sry)