Fix -Wsingle-bit-bitfield-constant-conversion warning in clang 16 report: /src/le/libevent/sample/becat.c:304:29: warning: implicit truncation from 'int' to a one-bit wide bit-field changes value from 1 to -1 [-Wsingle-bit-bitfield-constant-conversion] case 'k': o.extra.keep = 1; break;