x3 rule limits ast struct fields number to 10 under msvc 2019/windows/boost 1.70

[rockonedege]

Here a rule that complies OK with clang under Linux, but fails with pages of error with MSVC 2019/Windows/Boost 1.70.

• ast:

struct mid0061_data_rev1 : mid_base<61, mid0061::revision::_1>
{
  std::uint32_t cell_id;
  std::uint8_t channel_id;
  std::string torque_controller_name; // 25 bytes
  std::string vin_id;                 // 25 bytes
  std::uint8_t job_id;
  
  std::uint16_t parameter_set_id;
  std::uint32_t batch_size;
  std::uint32_t batch_counter;
  std::uint8_t tightening_status;
  std::uint8_t torque_status;
  std::uint8_t angle_status;

  // 6 bytes each
  std::uint32_t torque_min_limit;
  std::uint32_t torque_max_limit;
  std::uint32_t torque_final_target;
  std::uint32_t torque;
  // 5 bytes each
  std::uint32_t angle_min_limit;
  std::uint32_t angle_max_limit;
  std::uint32_t angle_final_target;
  std::uint32_t angle;

  std::string timestamp_tightening;                    // 19 byte
  std::string timestamp_last_parameter_setting_change; // 19 byte

  std::uint8_t batch_status;
  std::uint32_t tightening_id; // 10 byte
};

• rule:

namespace x3 = boost::spirit::x3;

auto const uint_1_digit = x3::uint_parser<std::uint8_t, 10, 1, 1>{};
auto const uint_2_digits = x3::uint_parser<std::uint8_t, 10, 2, 2>{};
auto const uint_3_digits = x3::uint_parser<std::uint32_t, 10, 3, 3>{};
auto const uint_4_digits = x3::uint_parser<std::uint32_t, 10, 4, 4>{};
auto const uint_5_digits = x3::uint_parser<std::uint32_t, 10, 5, 5>{};
auto const uint_6_digits = x3::uint_parser<std::uint32_t, 10, 6, 6>{};
auto const uint_10_digits = x3::uint_parser<std::uint32_t, 10, 10, 10>{};

auto const r_def = lit("01") >> uint_4_digits            // cell_id;
                  //  >> lit("02") >> uint_2_digits         // channel_id;
                  //  >> lit("03") >> repeat(25)[x3::char_] // torque_controller_name;
                  //  >> lit("04") >> repeat(25)[x3::char_] // vin_id;
                  //  >> lit("05") >> uint_2_digits         // job_id;
                  //  >> lit("06") >> uint_3_digits         // parameter_set_id;

                  //  >> lit("07") >> uint_4_digits // batch_size;
                  //  >> lit("08") >> uint_4_digits // batch_counter;
                  //  >> lit("09") >> uint_1_digit  // tightening_status;
                  //  >> lit("10") >> uint_1_digit  // torque_status;
                  //  >> lit("11") >> uint_1_digit  // angle_status;

                  //  >> lit("12") >> uint_6_digits // torque_min_limit;
                  //  >> lit("13") >> uint_6_digits // torque_max_limit;
                  //  >> lit("14") >> uint_6_digits // torque_finalarget;
                   >> lit("15") >> uint_6_digits // torque;

                   >> lit("16") >> uint_5_digits // angle_min_limit;
                   >> lit("17") >> uint_5_digits // angle_max_limit;
                   >> lit("18") >> uint_5_digits // angle_finalarget;
                   >> lit("19") >> uint_5_digits // angle;

                   >> lit("20") >> repeat(19)[x3::char_] //  timestamp; // 19 byte
                   >> lit("21") >> repeat(19)[x3::char_] //  timestamp; // 19 byte

                   >> lit("22") >> uint_1_digit   //  batch_status;
                   >> lit("23") >> uint_10_digits //  tightening_id; // 10 byte
    ;

• adaptation

BOOST_FUSION_ADAPT_STRUCT(open_protocol::ast::tightening::mid0061_data_rev1,
                          cell_id,
                          // channel_id,
                          // torque_controller_name,
                          // vin_id,
                          // job_id,
                          // parameter_set_id,

                          // batch_size,
                          // batch_counter,
                          // tightening_status,
                          // torque_status,
                          // angle_status,

                          // torque_min_limit,
                          // torque_max_limit,
                          // torque_final_target,
                          torque,

                          angle_min_limit,
                          angle_max_limit,
                          angle_final_target,
                          angle,

                          timestamp_tightening,
                          timestamp_last_parameter_setting_change,

                          batch_status,
                          tightening_id
                          )

the error says it has something to do with the rule def.
The error is too long to past here, which I could do if requested.

While debugging it starting with one field and adding another. I found that it not the parsers but the total number of parsers that fails the compilation.

selecting any combination of 10 or under will compile just fine. One more will fail it.

I suspect it has something to do with BOOST_FUSION_ADAPT_STRUCT with MSVC, a default limit is set somewhere.

Is this by design or a bug in x3 or MSVC? How can I workaround it?

[djowel]

I suspect this falls more under Fusion, rather than Spirit. Please provide a minimum compilable self contained test code, plus the errors, so we can determine where this issue falls under.

[rockonedege]

Thanks for investigating.

Below is the minimum example code that fails to compile. It compiles ok if keep the struct member count under 10.

#include <boost/config/warning_disable.hpp>
#include <boost/spirit/home/x3.hpp>

#include <boost/fusion/include/adapt_struct.hpp>


namespace open_protocol::ast::tightening
{

struct mid0061_data_rev1
{
  std::uint32_t cell_id;
  std::uint8_t channel_id;
  std::string torque_controller_name; // 25 bytes
  std::string vin_id;                 // 25 bytes
  std::uint8_t job_id;
  std::uint16_t parameter_set_id;

  std::uint32_t batch_size;
  std::uint32_t batch_counter;
  std::uint8_t tightening_status;
  std::uint8_t torque_status;
  std::uint8_t angle_status;

  // 6 bytes each
  std::uint32_t torque_min_limit;
  std::uint32_t torque_max_limit;
  std::uint32_t torque_final_target;
  std::uint32_t torque;

  // 5 bytes each
  std::uint32_t angle_min_limit;
  std::uint32_t angle_max_limit;
  std::uint32_t angle_final_target;
  std::uint32_t angle;

  std::string timestamp_tightening;                    // 19 bytes
  std::string timestamp_last_parameter_setting_change; // 19 bytes

  std::uint8_t batch_status;
  std::uint32_t tightening_id; // 10 bytes
};
} // namespace open_protocol::ast::tightening


BOOST_FUSION_ADAPT_STRUCT(open_protocol::ast::tightening::mid0061_data_rev1,
                          cell_id,
                          channel_id,
                          torque_controller_name,
                          vin_id,
                          job_id,
                          parameter_set_id,

                          batch_size,
                          batch_counter,
                          tightening_status,
                          torque_status,
                          angle_status,

                          torque_min_limit,
                          torque_max_limit,
                          torque_final_target,
                          torque,

                          angle_min_limit,
                          angle_max_limit,
                          angle_final_target,
                          angle,

                          timestamp_tightening,
                          timestamp_last_parameter_setting_change,

                          batch_status,
                          tightening_id
                          )

namespace open_protocol::parser::tightening::mid0061_data_rev1
{
namespace x3 = boost::spirit::x3;
namespace ascii = x3::ascii;

using x3::lit;
using x3::repeat;

auto const uint_1_digit = x3::uint_parser<std::uint8_t, 10, 1, 1>{};
auto const uint_2_digits = x3::uint_parser<std::uint8_t, 10, 2, 2>{};
auto const uint_3_digits = x3::uint_parser<std::uint32_t, 10, 3, 3>{};
auto const uint_4_digits = x3::uint_parser<std::uint32_t, 10, 4, 4>{};
auto const uint_5_digits = x3::uint_parser<std::uint32_t, 10, 5, 5>{};
auto const uint_6_digits = x3::uint_parser<std::uint32_t, 10, 6, 6>{};
auto const uint_10_digits = x3::uint_parser<std::uint32_t, 10, 10, 10>{};

using rule_type = x3::rule<class mid0061_data_rev1_class, open_protocol::ast::tightening::mid0061_data_rev1>;

rule_type const r = "mid0061_data_rev1";

auto const r_def = lit("01") >> uint_4_digits               // cell_id;
                   >> lit("02") >> uint_2_digits            // channel_id;
                   >> lit("03") >> repeat(25)[ascii::char_] // torque_controller_name;
                   >> lit("04") >> repeat(25)[ascii::char_] // vin_id;
                   >> lit("05") >> uint_2_digits            // job_id;
                   >> lit("06") >> uint_3_digits            // parameter_set_id;

                   >> lit("07") >> uint_4_digits // batch_size;
                   >> lit("08") >> uint_4_digits // batch_counter;
                   >> lit("09") >> uint_1_digit  // tightening_status;
                   >> lit("10") >> uint_1_digit  // torque_status;
                   >> lit("11") >> uint_1_digit  // angle_status;

                   >> lit("12") >> uint_6_digits // torque_min_limit;
                   >> lit("13") >> uint_6_digits // torque_max_limit;
                   >> lit("14") >> uint_6_digits // torque_finalarget;
                   >> lit("15") >> uint_6_digits // torque;

                   >> lit("16") >> uint_5_digits            // angle_min_limit;
                   >> lit("17") >> uint_5_digits            // angle_max_limit;
                   >> lit("18") >> uint_5_digits            // angle_finalarget;
                   >> lit("19") >> uint_5_digits            // angle;


                   >> lit("20") >> repeat(19)[ascii::char_] //  timestamp; // 19 bytes
                   >> lit("21") >> repeat(19)[ascii::char_] //  timestamp; // 19 bytes
                   >> lit("22") >> uint_1_digit             //  batch_status;
                   >> lit("23") >> uint_10_digits           //  tightening_id; // 10 bytes
    ;

} // namespace open_protocol::parser::tightening::mid0061_data_rev1

namespace open_protocol::parser::tightening::mid0061_data_rev1
{
BOOST_SPIRIT_DEFINE(r);

rule_type rule()
{
  return r;
}

using iterator_type = std::string::const_iterator;
BOOST_SPIRIT_INSTANTIATE(rule_type, iterator_type, x3::unused_type);
} // namespace open_protocol::parser::tightening::mid0061_data_rev1

int main()
{
}

[djowel]

Thanks. I'll have a look as soon as I can. I do not have MSVC 2019 at the moment.

[rockonedege]

Yesterday, I updated vs2017 to the latest patch and found the error threshold to be 20, which happens to be the default mpl::vector size, as I noticed vector20 from the error message.

Trying to prepend the following lines at the very top does make it to vector30 , the compilation still failed.

#define BOOST_MPL_CFG_NO_PREPROCESSED_HEADERS
#define BOOST_MPL_LIMIT_VECTOR_SIZE 30

it looks to have something to do with mpl, but I am not sure where the problem is.

[rockonedege]

my bad, setting #define BOOST_MPL_LIMIT_VECTOR_SIZE 50 fixed it. No I wonder why it's not a problem with Clang/Linux.

[djowel]

my bad, setting #define BOOST_MPL_LIMIT_VECTOR_SIZE 50 fixed it. No I wonder why it's not a problem with Clang/Linux.

I suspect it's because some code are on different #ifdef code paths, because of late c++ conformance with MSVC compilers. I'd still want to investigate, so let's keep this open.