OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=22925
Crash type: Index-out-of-bounds Crash state: parse_exp parse_branch parse_alts
{ "severity": "MEDIUM", "introduced_range": "efa4e3afb3926b2899e09a0d7c73bc7914e30c3a:bcccd7929f794d3ab5cb59c9fb1146322cd5510b" }