[509] % cvc5 -q --re-elim --re-elim-agg small.smt2 
Fatal failure within static cvc5::Node cvc5::theory::strings::RegExpElimination::eliminateStar(cvc5::Node, bool) at /local/suz-local/software/CVC4/src/theory/strings/regexp_elim.cpp:565
Check failure

 regexp_ch.getKind() != STRING_IN_REGEXP

Aborted
[510] % 
[510] % cat small.smt2 
(declare-const x String)
(assert (str.in_re x (re.* (re.union (re.range x x) (str.to_re "ab")))))
(check-sat)
[511] %