Erreur de compilation avec boost :: spirit :: x3

Question

J'ai essayé de compiler example file avec gcc 5.3.1 (5.3.1 20160406 (Red Hat 5.3.1-6) (GCC)), boost 1.61.0.

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

#include <iostream> 

// Presented are various ways to attach semantic actions 
// * Using plain function pointer 
// * Using simple function object 

namespace client 
{ 
    namespace x3 = boost::spirit::x3; 
    using x3::_attr; 

    struct print_action 
    {  
     template <typename Context> 
     void operator()(Context const& ctx) const 
     { 
      std::cout << _attr(ctx) << std::endl; 
     } 
    }; 
} 

int main() 
{ 
    using boost::spirit::x3::int_; 
    using boost::spirit::x3::parse; 
    using client::print_action; 

    { // example using function object 

     char const *first = "{43}", *last = first + std::strlen(first); 
     parse(first, last, '{' >> int_[print_action()] >> '}'); 
    } 

    { // example using C++14 lambda 

     char const *first = "{44}", *last = first + std::strlen(first); 
     auto f = [](auto& ctx){ std::cout << _attr(ctx) << std::endl; }; 
     parse(first, last, '{' >> int_[f] >> '}'); 
    } 

    return 0; 
} 

La commande est la compilation: g++ test.cpp -std=c++1y (je viens rebaptisés le fichier.)

j'ai eu l'erreur suivante:

test.cpp: In instantiation of ‘main()::<lambda(auto:1&)> [with auto:1 = const boost::spirit::x3::context<boost::spirit::x3::attr_context_tag, int, boost::spirit::x3::context<boost::spirit::x3::where_context_tag, boost::iterator_range<const char*>, boost::spirit::x3::context<boost::spirit::x3::rule_val_context_tag, const boost::spirit::x3::unused_type, boost::spirit::x3::context<boost::spirit::x3::parse_pass_context_tag, bool, boost::spirit::x3::unused_type> > > >]’: 
/usr/local/include/boost/spirit/home/x3/support/utility/is_callable.hpp:20:35: required from ‘struct boost::spirit::x3::is_callable<main()::<lambda(auto:1&)>(const boost::spirit::x3::context<boost::spirit::x3::attr_context_tag, int, boost::spirit::x3::context<boost::spirit::x3::where_context_tag, boost::iterator_range<const char*>, boost::spirit::x3::context<boost::spirit::x3::rule_val_context_tag, const boost::spirit::x3::unused_type, boost::spirit::x3::context<boost::spirit::x3::parse_pass_context_tag, bool, boost::spirit::x3::unused_type> > > >&)>’ 
/usr/local/include/boost/spirit/home/x3/core/call.hpp:72:28: required from ‘auto boost::spirit::x3::call(F, Iterator&, const Iterator&, const Context&, RuleContext&, Attribute&) [with F = main()::<lambda(auto:1&)>; Iterator = const char*; Context = boost::spirit::x3::context<boost::spirit::x3::parse_pass_context_tag, bool, boost::spirit::x3::unused_type>; RuleContext = const boost::spirit::x3::unused_type; Attribute = int]’ 
/usr/local/include/boost/spirit/home/x3/core/action.hpp:45:17: required from ‘bool boost::spirit::x3::action<Subject, Action>::call_action(Iterator&, const Iterator&, const Context&, RuleContext&, Attribute&) const [with Iterator = const char*; Context = boost::spirit::x3::unused_type; RuleContext = const boost::spirit::x3::unused_type; Attribute = int; Subject = boost::spirit::x3::int_parser<int>; Action = main()::<lambda(auto:1&)>]’ 
/usr/local/include/boost/spirit/home/x3/core/action.hpp:57:32: required from ‘bool boost::spirit::x3::action<Subject, Action>::parse_main(Iterator&, const Iterator&, const Context&, RuleContext&, Attribute&) const [with Iterator = const char*; Context = boost::spirit::x3::unused_type; RuleContext = const boost::spirit::x3::unused_type; Attribute = int; Subject = boost::spirit::x3::int_parser<int>; Action = main()::<lambda(auto:1&)>]’ 
/usr/local/include/boost/spirit/home/x3/operator/sequence.hpp:32:17: recursively required from ‘bool boost::spirit::x3::sequence<Left, Right>::parse(Iterator&, const Iterator&, const Context&, RContext&, boost::spirit::x3::unused_type) const [with Iterator = const char*; Context = boost::spirit::x3::unused_type; RContext = const boost::spirit::x3::unused_type; Left = boost::spirit::x3::literal_char<boost::spirit::char_encoding::standard, boost::spirit::x3::unused_type>; Right = boost::spirit::x3::action<boost::spirit::x3::int_parser<int>, main()::<lambda(auto:1&)> >]’ 
/usr/local/include/boost/spirit/home/x3/operator/sequence.hpp:32:17: required from ‘bool boost::spirit::x3::sequence<Left, Right>::parse(Iterator&, const Iterator&, const Context&, RContext&, boost::spirit::x3::unused_type) const [with Iterator = const char*; Context = boost::spirit::x3::unused_type; RContext = const boost::spirit::x3::unused_type; Left = boost::spirit::x3::sequence<boost::spirit::x3::literal_char<boost::spirit::char_encoding::standard, boost::spirit::x3::unused_type>, boost::spirit::x3::action<boost::spirit::x3::int_parser<int>, main()::<lambda(auto:1&)> > >; Right = boost::spirit::x3::literal_char<boost::spirit::char_encoding::standard, boost::spirit::x3::unused_type>]’ 
/usr/local/include/boost/spirit/home/x3/core/parse.hpp:35:68: required from ‘bool boost::spirit::x3::parse_main(Iterator&, Iterator, const Parser&, Attribute&) [with Iterator = const char*; Parser = boost::spirit::x3::sequence<boost::spirit::x3::sequence<boost::spirit::x3::literal_char<boost::spirit::char_encoding::standard, boost::spirit::x3::unused_type>, boost::spirit::x3::action<boost::spirit::x3::int_parser<int>, main()::<lambda(auto:1&)> > >, boost::spirit::x3::literal_char<boost::spirit::char_encoding::standard, boost::spirit::x3::unused_type> >; Attribute = const boost::spirit::x3::unused_type]’ 
/usr/local/include/boost/spirit/home/x3/core/parse.hpp:71:26: required from ‘bool boost::spirit::x3::parse(Iterator&, Iterator, const Parser&) [with Iterator = const char*; Parser = boost::spirit::x3::sequence<boost::spirit::x3::sequence<boost::spirit::x3::literal_char<boost::spirit::char_encoding::standard, boost::spirit::x3::unused_type>, boost::spirit::x3::action<boost::spirit::x3::int_parser<int>, main()::<lambda(auto:1&)> > >, boost::spirit::x3::literal_char<boost::spirit::char_encoding::standard, boost::spirit::x3::unused_type> >]’ 
test.cpp:47:49: required from here 
test.cpp:46:51: 错误：use of ‘template<class Context> decltype(auto) boost::spirit::x3::_attr(const Context&)’ before deduction of ‘auto’ 
     auto f = [](auto& ctx){ std::cout << _attr(ctx) << std::endl; }; 
               ^
test.cpp:46:51: 错误：use of ‘decltype(auto) boost::spirit::x3::_attr(const Context&) [with Context = boost::spirit::x3::context<boost::spirit::x3::attr_context_tag, int, boost::spirit::x3::context<boost::spirit::x3::where_context_tag, boost::iterator_range<const char*>, boost::spirit::x3::context<boost::spirit::x3::rule_val_context_tag, const boost::spirit::x3::unused_type, boost::spirit::x3::context<boost::spirit::x3::parse_pass_context_tag, bool, boost::spirit::x3::unused_type> > > >]’ before deduction of ‘auto’ 
In file included from /usr/local/include/boost/spirit/home/x3/core/action.hpp:13:0, 
       from /usr/local/include/boost/spirit/home/x3/core.hpp:14, 
       from /usr/local/include/boost/spirit/home/x3.hpp:20, 
       from test.cpp:8: 
/usr/local/include/boost/spirit/home/x3/core/call.hpp: In instantiation of ‘auto boost::spirit::x3::call(F, Iterator&, const Iterator&, const Context&, RuleContext&, Attribute&) [with F = main()::<lambda(auto:1&)>; Iterator = const char*; Context = boost::spirit::x3::context<boost::spirit::x3::parse_pass_context_tag, bool, boost::spirit::x3::unused_type>; RuleContext = const boost::spirit::x3::unused_type; Attribute = int]’: 
/usr/local/include/boost/spirit/home/x3/core/action.hpp:45:17: required from ‘bool boost::spirit::x3::action<Subject, Action>::call_action(Iterator&, const Iterator&, const Context&, RuleContext&, Attribute&) const [with Iterator = const char*; Context = boost::spirit::x3::unused_type; RuleContext = const boost::spirit::x3::unused_type; Attribute = int; Subject = boost::spirit::x3::int_parser<int>; Action = main()::<lambda(auto:1&)>]’ 
/usr/local/include/boost/spirit/home/x3/core/action.hpp:57:32: required from ‘bool boost::spirit::x3::action<Subject, Action>::parse_main(Iterator&, const Iterator&, const Context&, RuleContext&, Attribute&) const [with Iterator = const char*; Context = boost::spirit::x3::unused_type; RuleContext = const boost::spirit::x3::unused_type; Attribute = int; Subject = boost::spirit::x3::int_parser<int>; Action = main()::<lambda(auto:1&)>]’ 
/usr/local/include/boost/spirit/home/x3/operator/sequence.hpp:32:17: recursively required from ‘bool boost::spirit::x3::sequence<Left, Right>::parse(Iterator&, const Iterator&, const Context&, RContext&, boost::spirit::x3::unused_type) const [with Iterator = const char*; Context = boost::spirit::x3::unused_type; RContext = const boost::spirit::x3::unused_type; Left = boost::spirit::x3::literal_char<boost::spirit::char_encoding::standard, boost::spirit::x3::unused_type>; Right = boost::spirit::x3::action<boost::spirit::x3::int_parser<int>, main()::<lambda(auto:1&)> >]’ 
/usr/local/include/boost/spirit/home/x3/operator/sequence.hpp:32:17: required from ‘bool boost::spirit::x3::sequence<Left, Right>::parse(Iterator&, const Iterator&, const Context&, RContext&, boost::spirit::x3::unused_type) const [with Iterator = const char*; Context = boost::spirit::x3::unused_type; RContext = const boost::spirit::x3::unused_type; Left = boost::spirit::x3::sequence<boost::spirit::x3::literal_char<boost::spirit::char_encoding::standard, boost::spirit::x3::unused_type>, boost::spirit::x3::action<boost::spirit::x3::int_parser<int>, main()::<lambda(auto:1&)> > >; Right = boost::spirit::x3::literal_char<boost::spirit::char_encoding::standard, boost::spirit::x3::unused_type>]’ 
/usr/local/include/boost/spirit/home/x3/core/parse.hpp:35:68: required from ‘bool boost::spirit::x3::parse_main(Iterator&, Iterator, const Parser&, Attribute&) [with Iterator = const char*; Parser = boost::spirit::x3::sequence<boost::spirit::x3::sequence<boost::spirit::x3::literal_char<boost::spirit::char_encoding::standard, boost::spirit::x3::unused_type>, boost::spirit::x3::action<boost::spirit::x3::int_parser<int>, main()::<lambda(auto:1&)> > >, boost::spirit::x3::literal_char<boost::spirit::char_encoding::standard, boost::spirit::x3::unused_type> >; Attribute = const boost::spirit::x3::unused_type]’ 
/usr/local/include/boost/spirit/home/x3/core/parse.hpp:71:26: required from ‘bool boost::spirit::x3::parse(Iterator&, Iterator, const Parser&) [with Iterator = const char*; Parser = boost::spirit::x3::sequence<boost::spirit::x3::sequence<boost::spirit::x3::literal_char<boost::spirit::char_encoding::standard, boost::spirit::x3::unused_type>, boost::spirit::x3::action<boost::spirit::x3::int_parser<int>, main()::<lambda(auto:1&)> > >, boost::spirit::x3::literal_char<boost::spirit::char_encoding::standard, boost::spirit::x3::unused_type> >]’ 
test.cpp:47:49: required from here 
/usr/local/include/boost/spirit/home/x3/core/call.hpp:72:28: 错误：use of ‘auto boost::spirit::x3::detail::call(F, const Context&, mpl_::true_) [with F = main()::<lambda(auto:1&)>; Context = boost::spirit::x3::context<boost::spirit::x3::attr_context_tag, int, boost::spirit::x3::context<boost::spirit::x3::where_context_tag, boost::iterator_range<const char*>, boost::spirit::x3::context<boost::spirit::x3::rule_val_context_tag, const boost::spirit::x3::unused_type, boost::spirit::x3::context<boost::spirit::x3::parse_pass_context_tag, bool, boost::spirit::x3::unused_type> > > >; mpl_::true_ = mpl_::bool_<true>]’ before deduction of ‘auto’ 
     return detail::call(f, attr_context, is_callable<F(decltype(attr_context) const&)>()); 
          ^

Je me demande ce qui conduit à cette erreur?

P.S: Dans le fichier, 错误 signifie Erreur.

Answer 1

Note It looks like you linked the wrong sample file. My answer responds to the code shown in the error message instead.

Je ne peux pas reproduire le problème, mais je me souviens avoir vu quelque chose de similaire une fois.

Il semble que GCC ait parfois du mal à faire des ADL pour un type de paramètre lambda polymorphe.

La façon dont je suis autour de lui était de désactiver il ADL:

auto f = [](auto& ctx){ std::cout << x3::_attr(ctx) << std::endl; }; 

ou:

auto f = [](auto& ctx){ std::cout << (_attr)(ctx) << std::endl; };