Problem in calling “enqueue_work” - vorbrodt thread_pool

Question

I'm trying to use vorbrodt's thread-pool implementation in my code: https://vorbrodt.blog/2019/02/27/advanced-thread-pool/

So, I have a function with this signature:

static void InvokeJob( std::unique_ptr<BaseService> svc );

And, I'm trying to enqueue some jobs in thread_pool via:

pApp->pThreadPool->enqueue_work( App::InvokeJob, std::move( svc ) );

But it'll be failed in compilation:

In file included from /home/user1/testprj/project1/app/App.cpp:5:
In file included from /home/user1/testprj/project1/app/App.h:9:
In file included from /home/user1/testprj/project1/app/def.h:9:
In file included from /usr/include/c++/v1/iostream:38:
In file included from /usr/include/c++/v1/ios:216:
In file included from /usr/include/c++/v1/__locale:15:
In file included from /usr/include/c++/v1/string:505:
In file included from /usr/include/c++/v1/string_view:176:
In file included from /usr/include/c++/v1/__string:57:
In file included from /usr/include/c++/v1/algorithm:644:
In file included from /usr/include/c++/v1/memory:663:
/usr/include/c++/v1/tuple:1358:5: error: attempt to use a deleted function
    _VSTD::__invoke_constexpr(
    ^
/usr/include/c++/v1/__config:816:15: note: expanded from macro '_VSTD'
#define _VSTD std::_LIBCPP_ABI_NAMESPACE
              ^
/usr/include/c++/v1/tuple:1355:26: note: in instantiation of exception specification for '__apply_tuple_impl<void (*const &)(std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> >), const std::__1::tuple<std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> > > &, 0>' requested here
constexpr decltype(auto) __apply_tuple_impl(_Fn && __f, _Tuple && __t,
                         ^
/usr/include/c++/v1/tuple:1367:12: note: in instantiation of function template specialization 'std::__1::__apply_tuple_impl<void (*const &)(std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> >), const std::__1::tuple<std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> > > &, 0>' requested here
    _VSTD::__apply_tuple_impl(
           ^
/usr/include/c++/v1/tuple:1365:26: note: in instantiation of exception specification for 'apply<void (*const &)(std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> >), const std::__1::tuple<std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> > > &>' requested here
constexpr decltype(auto) apply(_Fn && __f, _Tuple && __t)
                         ^
/home/user1/testprj/project1/app/include/vorbrodt/pool.hpp:112:99: note: in instantiation of function template specialization 'std::__1::apply<void (*const &)(std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> >), const std::__1::tuple<std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> > > &>' requested here
                auto work = [p = std::forward<F>(f), t = std::make_tuple(std::forward<Args>(args)...)]() { std::apply(p, t); };
                                                                                                                ^
/home/user1/testprj/project1/app/App.cpp:221:27: note: in instantiation of function template specialization 'thread_pool::enqueue_work<void (&)(std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> >), std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> > >' requested here
    pApp->pThreadPool->enqueue_work( App::InvokeJob, std::move( svc ) );
                          ^
/usr/include/c++/v1/type_traits:1678:5: note: '~__nat' has been explicitly marked deleted here
    ~__nat() = delete;
    ^
In file included from /home/user1/testprj/project1/app/App.cpp:5:
In file included from /home/user1/testprj/project1/app/App.h:9:
In file included from /home/user1/testprj/project1/app/def.h:9:
In file included from /usr/include/c++/v1/iostream:38:
In file included from /usr/include/c++/v1/ios:216:
In file included from /usr/include/c++/v1/__locale:15:
In file included from /usr/include/c++/v1/string:505:
In file included from /usr/include/c++/v1/string_view:176:
In file included from /usr/include/c++/v1/__string:57:
In file included from /usr/include/c++/v1/algorithm:644:
In file included from /usr/include/c++/v1/memory:663:
/usr/include/c++/v1/tuple:1358:5: error: attempt to use a deleted function
    _VSTD::__invoke_constexpr(
    ^
/usr/include/c++/v1/__config:816:15: note: expanded from macro '_VSTD'
#define _VSTD std::_LIBCPP_ABI_NAMESPACE
              ^
/usr/include/c++/v1/tuple:1367:12: note: in instantiation of function template specialization 'std::__1::__apply_tuple_impl<void (*const &)(std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> >), const std::__1::tuple<std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> > > &, 0>' requested here
    _VSTD::__apply_tuple_impl(
           ^
/usr/include/c++/v1/tuple:1365:26: note: in instantiation of exception specification for 'apply<void (*const &)(std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> >), const std::__1::tuple<std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> > > &>' requested here
constexpr decltype(auto) apply(_Fn && __f, _Tuple && __t)
                         ^
/home/user1/testprj/project1/app/include/vorbrodt/pool.hpp:112:99: note: in instantiation of function template specialization 'std::__1::apply<void (*const &)(std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> >), const std::__1::tuple<std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> > > &>' requested here
                auto work = [p = std::forward<F>(f), t = std::make_tuple(std::forward<Args>(args)...)]() { std::apply(p, t); };
                                                                                                                ^
/home/user1/testprj/project1/app/App.cpp:221:27: note: in instantiation of function template specialization 'thread_pool::enqueue_work<void (&)(std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> >), std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> > >' requested here
    pApp->pThreadPool->enqueue_work( App::InvokeJob, std::move( svc ) );
                          ^
/usr/include/c++/v1/type_traits:1678:5: note: '~__nat' has been explicitly marked deleted here
    ~__nat() = delete;
    ^
In file included from /home/user1/testprj/project1/app/App.cpp:5:
In file included from /home/user1/testprj/project1/app/App.h:9:
In file included from /home/user1/testprj/project1/app/def.h:9:
In file included from /usr/include/c++/v1/iostream:38:
In file included from /usr/include/c++/v1/ios:216:
In file included from /usr/include/c++/v1/__locale:15:
In file included from /usr/include/c++/v1/string:505:
In file included from /usr/include/c++/v1/string_view:176:
In file included from /usr/include/c++/v1/__string:57:
In file included from /usr/include/c++/v1/algorithm:644:
In file included from /usr/include/c++/v1/memory:663:
/usr/include/c++/v1/tuple:1367:5: error: no matching function for call to '__apply_tuple_impl'
    _VSTD::__apply_tuple_impl(
    ^~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/v1/__config:816:15: note: expanded from macro '_VSTD'
#define _VSTD std::_LIBCPP_ABI_NAMESPACE
              ^
/usr/include/c++/v1/tuple:1351:79: note: expanded from macro '_LIBCPP_NOEXCEPT_RETURN'
#define _LIBCPP_NOEXCEPT_RETURN(...) noexcept(noexcept(__VA_ARGS__)) { return __VA_ARGS__; }
                                                                              ^~~~~~~~~~~
/home/user1/testprj/project1/app/include/vorbrodt/pool.hpp:112:99: note: in instantiation of function template specialization 'std::__1::apply<void (*const &)(std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> >), const std::__1::tuple<std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> > > &>' requested here
                auto work = [p = std::forward<F>(f), t = std::make_tuple(std::forward<Args>(args)...)]() { std::apply(p, t); };
                                                                                                                ^
/home/user1/testprj/project1/app/App.cpp:221:27: note: in instantiation of function template specialization 'thread_pool::enqueue_work<void (&)(std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> >), std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> > >' requested here
    pApp->pThreadPool->enqueue_work( App::InvokeJob, std::move( svc ) );
                          ^
/usr/include/c++/v1/tuple:1355:26: note: candidate template ignored: substitution failure [with _Fn = void (*const &)(std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> >), _Tuple = const std::__1::tuple<std::__1::unique_ptr<BaseService, std::__1::default_delete<BaseService> > > &, _Id = <0>]
constexpr decltype(auto) __apply_tuple_impl(_Fn && __f, _Tuple && __t,
                         ^
3 errors generated.
gmake[3]: *** [CMakeFiles/app_ocs.dir/build.make:107: CMakeFiles/app_ocs.dir/App.cpp.o] Error 1
gmake[3]: *** Waiting for unfinished jobs....
gmake[2]: *** [CMakeFiles/Makefile2:96: CMakeFiles/app_ocs.dir/all] Error 2
gmake[1]: *** [CMakeFiles/Makefile2:103: CMakeFiles/app_ocs.dir/rule] Error 2
gmake: *** [Makefile:138: app_ocs] Error 2

Can anybody help me out, Thanks.

Answer 1

first, thanks for reading my blog ;)

I get the same error :( looks like the way unique_ptr is forwarded to the worker lambda is not working like it should. easiest fix is to use a shared_ptr instead, that will work. otherwise I will have to think on it for a bit to see if I can come up with a fix...