Boost library spirit failed to build due to .\boost/spirit/home/qi/nonterminal/rule.hpp(304): error C2664: 'bool boost::function4<R,T0,T1,T2,T3>::operator ()(T0,T1,T2,T3) const': cannot convert argument 4 from 'const Skipper' to 'T3'

[spacelg]

Environment:
VS 2017 + Windows Server 2016

Issue description:
We build and run test for Boost. And we found grammar_fail.cpp failed to build due to error C2664: 'bool boost::function4<R,T0,T1,T2,T3>::operator ()(T0,T1,T2,T3) const': cannot convert argument 4 from 'const Skipper' to 'T3'. Could you pleaes take a look? Thanks in advance.

Error info:
compile-c-c++ ..\out\x86rel\boost\bin.v2\libs\spirit\test\qi\qi_grammar_fail.test\msvc-14.1\release\threading-multi\qi_grammar_fail.obj
grammar_fail.cpp
.\boost/spirit/home/qi/nonterminal/rule.hpp(304): error C2664: 'bool
log_x86_test_99.log
boost::function4<R,T0,T1,T2,T3>::operator ()(T0,T1,T2,T3) const': cannot convert argument 4 from 'const Skipper' to 'T3'
with
[
R=bool,
T0=const char *&,
T1=const char *const &,
T2=boost::spirit::context<boost::fusion::cons<boost::spirit::unused_type &,boost::fusion::nil_>,boost::fusion::vector<>> &,
T3=const boost::spirit::qi::reference<const boost::spirit::qi::rule<const char *,boost::spirit::unused_type,boost::spirit::unused_type,boost::spirit::unused_type,boost::spirit::unused_type>> &
]
and
[
Skipper=skipper_type
]
and
[
T3=const boost::spirit::qi::reference<const boost::spirit::qi::rule<const char *,boost::spirit::unused_type,boost::spirit::unused_type,boost::spirit::unused_type,boost::spirit::unused_type>> &
]
.\boost/spirit/home/qi/nonterminal/rule.hpp(304): note: Reason: cannot convert from 'const Skipper' to 'const boost::spirit::qi::reference<const boost::spirit::qi::rule<const char *,boost::spirit::unused_type,boost::spirit::unused_type,boost::spirit::unused_type,boost::spirit::unused_type>>'
with
[
Skipper=skipper_type
]
.\boost/spirit/home/qi/nonterminal/rule.hpp(304): note: No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called
.\boost/spirit/home/qi/reference.hpp(43): note: see reference to function template instantiation 'bool boost::spirit::qi::rule<Iterator,T1,T2,T3,T4>::parse<Context,Skipper,Attribute>(Iterator &,const Iterator &,Context &,const Skipper &,Attribute &) const' being compiled
with
[
Iterator=const char *,
T1=boost::spirit::qi::rule<const char *,boost::spirit::unused_type,boost::spirit::unused_type,boost::spirit::unused_type,boost::spirit::unused_type>,
T2=boost::spirit::unused_type,
T3=boost::spirit::unused_type,
T4=boost::spirit::unused_type,
Context=const boost::spirit::unused_type,
Skipper=skipper_type,
Attribute=const boost::spirit::unused_type
]
.\boost/spirit/home/qi/reference.hpp(43): note: see reference to function template instantiation 'bool boost::spirit::qi::rule<Iterator,T1,T2,T3,T4>::parse<Context,Skipper,Attribute>(Iterator &,const Iterator &,Context &,const Skipper &,Attribute &) const' being compiled
with
[
Iterator=const char *,
T1=boost::spirit::qi::rule<const char *,boost::spirit::unused_type,boost::spirit::unused_type,boost::spirit::unused_type,boost::spirit::unused_type>,
T2=boost::spirit::unused_type,
T3=boost::spirit::unused_type,
T4=boost::spirit::unused_type,
Context=const boost::spirit::unused_type,
Skipper=skipper_type,
Attribute=const boost::spirit::unused_type
]
.\boost/spirit/home/qi/detail/parse.hpp(85): note: see reference to function template instantiation 'bool boost::spirit::qi::reference<const boost::spirit::qi::rule<Iterator,T1,T2,T3,T4>>::parse<Iterator,const boost::spirit::unused_type,skipper_type,const boost::spirit::unused_type>(Iterator &,const Iterator &,Context &,const Skipper &,Attribute &) const' being compiled
with
[
Iterator=const char *,
T1=boost::spirit::qi::rule<const char *,boost::spirit::unused_type,boost::spirit::unused_type,boost::spirit::unused_type,boost::spirit::unused_type>,
T2=boost::spirit::unused_type,
T3=boost::spirit::unused_type,
T4=boost::spirit::unused_type,
Context=const boost::spirit::unused_type,
Skipper=skipper_type,
Attribute=const boost::spirit::unused_type
]
.\boost/spirit/home/qi/detail/parse.hpp(84): note: see reference to function template instantiation 'bool boost::spirit::qi::reference<const boost::spirit::qi::rule<Iterator,T1,T2,T3,T4>>::parse<Iterator,const boost::spirit::unused_type,skipper_type,const boost::spirit::unused_type>(Iterator &,const Iterator &,Context &,const Skipper &,Attribute &) const' being compiled
with
[
Iterator=const char *,
T1=boost::spirit::qi::rule<const char *,boost::spirit::unused_type,boost::spirit::unused_type,boost::spirit::unused_type,boost::spirit::unused_type>,
T2=boost::spirit::unused_type,
T3=boost::spirit::unused_type,
T4=boost::spirit::unused_type,
Context=const boost::spirit::unused_type,
Skipper=skipper_type,
Attribute=const boost::spirit::unused_type
]
.\boost/spirit/home/qi/parse.hpp(121): note: see reference to function template instantiation 'bool boost::spirit::qi::detail::phrase_parse_impl<Expr,void>::call<Iterator,Skipper>(Iterator &,Iterator,const Expr &,const Skipper &,boost::spirit::qi::skip_flag)' being compiled
with
[
Expr=num_list,
Iterator=const char *,
Skipper=boost::proto::exprns_::expr<boost::proto::tagns_::tag::bitwise_or,boost::proto::argsns_::list2<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::spirit::tag::char_codeboost::spirit::tag::space,boost::spirit::char_encoding::standard>,0> &,const boost::proto::exprns_::expr<boost::proto::tagns_::tag::shift_right,boost::proto::argsns_::list2<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::shift_right,boost::proto::argsns_::list2<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<const char &>,0>,const boost::proto::exprns_::expr<boost::proto::tagns_::tag::dereference,boost::proto::argsns_::list1<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::complement,boost::proto::argsns_::list1<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::spirit::terminal_ex<boost::spirit::tag::standard::char_,boost::fusion::vector>>,0> &>,1> &>,1> &>,2> &,boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<const char &>,0>>,2> &>,2>
]
.\boost/spirit/home/qi/parse.hpp(120): note: see reference to function template instantiation 'bool boost::spirit::qi::detail::phrase_parse_impl<Expr,void>::call<Iterator,Skipper>(Iterator &,Iterator,const Expr &,const Skipper &,boost::spirit::qi::skip_flag)' being compiled
with
[
Expr=num_list,
Iterator=const char ,
Skipper=boost::proto::exprns_::expr<boost::proto::tagns_::tag::bitwise_or,boost::proto::argsns_::list2<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::spirit::tag::char_codeboost::spirit::tag::space,boost::spirit::char_encoding::standard>,0> &,const boost::proto::exprns_::expr<boost::proto::tagns_::tag::shift_right,boost::proto::argsns_::list2<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::shift_right,boost::proto::argsns_::list2<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<const char &>,0>,const boost::proto::exprns_::expr<boost::proto::tagns_::tag::dereference,boost::proto::argsns_::list1<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::complement,boost::proto::argsns_::list1<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::spirit::terminal_ex<boost::spirit::tag::standard::char_,boost::fusion::vector>>,0> &>,1> &>,1> &>,2> &,boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<const char &>,0>>,2> &>,2>
]
libs\spirit\test\qi\grammar_fail.cpp(36): note: see reference to function template instantiation 'bool boost::spirit::qi::phrase_parse<const char,num_list,boost::proto::exprns_::expr<Tag,Args,2>>(Iterator &,Iterator,const Expr &,const Skipper &,boost::spirit::qi::skip_flag)' being compiled
with
[
Tag=boost::proto::tagns_::tag::bitwise_or,
Args=boost::proto::argsns_::list2<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::spirit::tag::char_codeboost::spirit::tag::space,boost::spirit::char_encoding::standard>,0> &,const boost::proto::exprns_::expr<boost::proto::tagns_::tag::shift_right,boost::proto::argsns_::list2<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::shift_right,boost::proto::argsns_::list2<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<const char &>,0>,const boost::proto::exprns_::expr<boost::proto::tagns_::tag::dereference,boost::proto::argsns_::list1<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::complement,boost::proto::argsns_::list1<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::spirit::terminal_ex<boost::spirit::tag::standard::char_,boost::fusion::vector>>,0> &>,1> &>,1> &>,2> &,boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<const char &>,0>>,2> &>,
Iterator=const char *,
Expr=num_list,
Skipper=boost::proto::exprns_::expr<boost::proto::tagns_::tag::bitwise_or,boost::proto::argsns_::list2<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::spirit::tag::char_codeboost::spirit::tag::space,boost::spirit::char_encoding::standard>,0> &,const boost::proto::exprns_::expr<boost::proto::tagns_::tag::shift_right,boost::proto::argsns_::list2<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::shift_right,boost::proto::argsns_::list2<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<const char &>,0>,const boost::proto::exprns_::expr<boost::proto::tagns_::tag::dereference,boost::proto::argsns_::list1<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::complement,boost::proto::argsns_::list1<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::spirit::terminal_ex<boost::spirit::tag::standard::char_,boost::fusion::vector>>,0> &>,1> &>,1> &>,2> &,boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<const char &>,0>>,2> &>,2>
]

[spacelg]

It is boost library spirit failed to build,so we close it and reopen the issue in boostorg/spirit.