Incorrect error parsing SELECT of constant expression with subtraction arithmetic

[cdmh]

Using a constant expression with a subtraction in a SELECT statement fails incorrectly. All of these statements cause error syntax error, unexpected INTVAL, expecting end of file.

SELECT 6-2;
SELECT 6-2-1;
SELECT 6+5/8*4-9;

However, other arithmetic operators work, including unary minus

SELECT 1.5*2.5;
SELECT 1.5*2.5*2;
SELECT 1+2;
SELECT 1+2+3;
SELECT 6/2;
SELECT 6/2/2;
SELECT -6;
SELECT -6+3;
SELECT -6.5;
SELECT -6.5+3;

Example:

hsql::SQLParserResult parser_result;
if (!(hsql::SQLParser::parse("SELECT 6-2;", &parser_result)  &&  parser_result.isValid()))
{
    std::ostringstream oss;
    oss << sql << '\n'
        << std::setw(parser_result.errorColumn()+7) << "^-----\n"
        << parser_result.errorMsg() << "\n";

    auto error = oss.str();
    throw std::runtime_error(error);
}

yields:

SELECT 6-2;
        ^-----
syntax error, unexpected INTVAL, expecting end of file

[mrks]

Thank you for the report. Flex prioritized unary minuses over binary minus expressions (i.e., subtractions). Could you please check if the mrks/fix_unary_minus solves your issue?

[cdmh]

Hi Markus, thanks for the quick response, and fix!
mrks/fix_unary_minus solves the errors, and all my tests pass.