[571] % cvc5 -q small.smt2
Fatal failure within unsigned int cvc5::String::front() const at /local/suz-local/software/CVC4/src/util/string.cpp:241
Check failure

 !d_str.empty()

Aborted
[572] % 
[572] % cat small.smt2
(declare-fun a () String)
(assert (ite (str.in_re (str.++ a "c") (re.* (re.range "a" ""))) (not (= a "")) (str.in_re a (re.* (re.range a "")))))
(check-sat)
[573] %