Recursive Serialization, decltype and is_visitable behaving strangely about visit_struct HOT 7 CLOSED

#include <stdio.h>
#include <stdlib.h>

#include <visit_struct/visit_struct.hpp>
#include <visit_struct/visit_struct_instrusive.hpp>

typedef struct Water {
    BEGIN_VISITABLES(Water);
    VISITABLE(float, x);
    VISITABLE(float, y);
    VISITABLE(float, z);
    END_VISITABLES;
} Water;

typedef struct Level {
    BEGIN_VISITABLES(Level);
    VISITABLE(Water*, waterTiles);
    VISITABLE(int, numWaterTiles);
    END_VISITABLES;
} Level;

template<typename T>
static void visitSerialize(const T& type) {
    visit_struct::for_each(type, [](const char* name, const auto & value) {
        if (visit_struct::traits::is_visitable<std::decay_t<decltype(value)>>::value) {
            printf("is visitable! %s", name);
        }
    });
}

int main(void) {
    Level level;
    level.waterTiles = (Water*) malloc(sizeof(Water) * 12);
    level.numWaterTiles = 12;

    visitSerialize(level);

    return 0;
}

// convert visitable struct to json; supports types that can be assigned to
// nlohmann::json, such as strings, doubles, as well as recursive std::vector
// and visistable structs;
template <class Value>
auto visitable_to_json(const Value& value) {
  nlohmann::json result;
  if constexpr (visit_struct::traits::is_visitable<Value>::value) {
    // visitable struct --> visit each member and save as json object
    visit_struct::for_each(value, [&](const char* name, const auto& member) {
      result[name] = visitable_to_json(member);
    });
  } else if constexpr (is_vector_v<Value>) {
    // vector --> recursively save elements to json array
    for (const auto& elem : value) {
      result.push_back(visitable_to_json(elem));
    }
  } else if constexpr (wise_enum::is_wise_enum_v<Value>) {
    // enum --> save as string
    result = wise_enum::to_string(value);
  } else {
    // other basic value (string, number, ...)
    result = value;
  }
  return result;
}