DATE subtract with INTERVAL is not parsed

[cdmh]

This query from tpc-h doesn't parse, and reports an error at column 75, inside interval '75'.

SELECT * FROM lineitem where l_shipdate <= date '1998-12-01' - interval '75' day (3);

This code

    REQUIRE(hsql::SQLParser::parse(
        "SELECT * FROM lineitem where l_shipdate <= date '1998-12-01' - interval '75' day (3);",
        &parser_result) == true);
    if (!parser_result.isValid())
        std::cerr << parser_result.errorMsg() << " at column " << parser_result.errorColumn();

yields

syntax error, unexpected STRING, expecting end of file at column 75