Exception of segment fail when run value_from for tree structuor

[akeyliu]

Exception of segment fail when run value_from for tree structuor

[grisumbras]

Given the information you've given me, I can't reproduce it. You should definitely at least provide your implementation of tag_invoke(value_from_tag). Even better if you provide a minimal reproduceable example, that is something I could just copy into an empty file and get your error.

[akeyliu]

I develop test source code and it's work. I need to check other source code. Sorry to bother you!
The test source code is like follow. I try to use reflect like macro function to automatically generate the value_from and value_to function for specific class/structor.
`
#include <boost/json/src.hpp>
#include
#include
#include <type_traits>

using namespace std;
using namespace boost;

struct CRouteData;
struct CRouteData {
int iCount;
list listSonRouteData;

friend void tag_invoke( const json::value_from_tag&, json::value &_j, CRouteData const &_t) {
    json::object _obj;
    _obj.emplace("iCount", json::value_from(_t.iCount));
    _obj.emplace("listSonRouteData", json::value_from(_t.listSonRouteData));
    _j.emplace_object() = _obj;
};
friend CRouteData tag_invoke( const json::value_to_tag<CRouteData>&, json::value const &_j ) {
    CRouteData _t;
    _t.iCount = json::value_to<decltype(_t.iCount)>(_j.at("iCount"));
    _t.listSonRouteData = json::value_to<decltype(_t.listSonRouteData)>(_j.at("listSonRouteData"));
    return _t;
};

};

int main(void) {
CRouteData objRouteData{0, {}}, objRouteDataSon1{2, {}}, objRouteDataSon2{3, {}};
list listData{objRouteData}, *ptrList = &listData;
for( auto iDepth = 0; iDepth < 100 && !ptrList->empty(); iDepth++ ) {
if( !ptrList->empty() )
ptrList = &(ptrList->back().listSonRouteData);
for( auto i = 0; i <= iDepth; i++) {
CRouteData objRouteDataNow{i, {}};
ptrList->emplace_back(objRouteDataNow);
}
cout << "iDepth:" << iDepth << " [" << json::value_from(ptrList->back()) << "] Total:" << json::value_from(listData) << endl;
}
return 0;
}
`