--- a/lib/ts_fsm.c~lib-ts_fsm-replace-zero-length-array-with-flexible-array-member +++ a/lib/ts_fsm.c @@ -32,7 +32,7 @@ struct ts_fsm { unsigned int ntokens; - struct ts_fsm_token tokens[0]; + struct ts_fsm_token tokens[]; }; /* other values derived from ctype.h */