I'm getting a really big, scary, puzzling error in some code I've been working on lately. Basically, I'm trying to declare a thread and put it inside a std::vector for safe keeping. However, for some reason this gets std::tuple involved, which doesn't like what I'm doing.
How do I fix this?
P.S. I've already looked at this. If the answer's there, I'm not seeing it.
synchronizer.cpp:
#include <sys/socket.h>
#include <vector>
#include <thread>
#include <iostream>
#define PACKET_SIZE 8192
class synchronizer
{
private:
int sock;
int* status;
public:
int start();
synchronizer(int socket, int* stat);
~synchronizer();
void operator()();
};
synchronizer::synchronizer(int socket, int* stat) : sock(socket), status(stat) {}
void synchronizer::operator()()
{
this->start();
}
int synchronizer::start()
{
std::cout << "Starting." << std::endl;
char buf[PACKET_SIZE];
if (recv(sock, buf, PACKET_SIZE, 0) == -1)
{
perror("Error receiving");
return -1;
}
return 0;
}
synchronizer::~synchronizer()
{
}
The relevant bits of server.cpp, which is the main file:
#include <iostream>
#include <thread>
#include "synchronizer.hpp"
inline int checkin (std::vector<std::thread> *pool, int conn, int *status)
{
synchronizer syncer = synchronizer(conn, status);
pool->push_back(std::thread(syncer));
return 0;
}
int main(void)
{
std::vector<std::thread> pool = {};
int status = 0;
// newfd being a socket file descriptor acquired earlier in the program's logic
checkin(&pool, newfd, &status);
}
And here's the error (compiling with option -pthread):
In file included from server.cpp:14:
/usr/include/c++/9/thread: In instantiation of ‘static std::thread::_Invoker<std::tuple<typename std::decay<_Tp>::type, typename std::decay<_Args>::type ...> > std::thread::__make_invoker(_Callable&&, _Args&& ...) [with _Callable = synchronizer&; _Args = {}; typename std::decay<_Tp>::type = synchronizer]’:
/usr/include/c++/9/thread:131:22: required from ‘std::thread::thread(_Callable&&, _Args&& ...) [with _Callable = synchronizer&; _Args = {}; <template-parameter-1-3> = void]’
server.cpp:44:49: required from here
/usr/include/c++/9/thread:267:4: error: no matching function for call to ‘std::tuple<synchronizer>::tuple(<brace-enclosed initializer list>)’
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:808:11: note: candidate: ‘template<class _Alloc, class _Dummy, class ... _UElements, typename std::enable_if<((std::tuple<synchronizer>::_TMCT<_UElements ...>::_MoveConstructibleTuple<_UElements ...>() && (! std::tuple<synchronizer>::_TMCT<_UElements ...>::_ImplicitlyMoveConvertibleTuple<_UElements ...>())) && std::tuple<synchronizer>::_TNTC<_Dummy>::_NonNestedTuple<tuple<_Tail ...>&&>()), bool>::type <anonymous> > std::tuple<_Elements>::tuple(std::allocator_arg_t, const _Alloc&, std::tuple<_Args2 ...>&&)’
808 | explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
| ^~~~~
/usr/include/c++/9/tuple:808:11: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: candidate expects 3 arguments, 1 provided
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:793:2: note: candidate: ‘template<class _Alloc, class _Dummy, class ... _UElements, typename std::enable_if<((std::tuple<synchronizer>::_TMCT<_UElements ...>::_MoveConstructibleTuple<_UElements ...>() && std::tuple<synchronizer>::_TMCT<_UElements ...>::_ImplicitlyMoveConvertibleTuple<_UElements ...>()) && std::tuple<synchronizer>::_TNTC<_Dummy>::_NonNestedTuple<tuple<_Tail ...>&&>()), bool>::type <anonymous> > std::tuple<_Elements>::tuple(std::allocator_arg_t, const _Alloc&, std::tuple<_Args2 ...>&&)’
793 | tuple(allocator_arg_t __tag, const _Alloc& __a,
| ^~~~~
/usr/include/c++/9/tuple:793:2: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: candidate expects 3 arguments, 1 provided
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:778:11: note: candidate: ‘template<class _Alloc, class _Dummy, class ... _UElements, typename std::enable_if<((std::tuple<synchronizer>::_TMCT<_UElements ...>::_ConstructibleTuple<_UElements ...>() && (! std::tuple<synchronizer>::_TMCT<_UElements ...>::_ImplicitlyConvertibleTuple<_UElements ...>())) && std::tuple<synchronizer>::_TNTC<_Dummy>::_NonNestedTuple<const tuple<_Tail ...>&>()), bool>::type <anonymous> > std::tuple<_Elements>::tuple(std::allocator_arg_t, const _Alloc&, const std::tuple<_Args2 ...>&)’
778 | explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
| ^~~~~
/usr/include/c++/9/tuple:778:11: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: candidate expects 3 arguments, 1 provided
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:763:2: note: candidate: ‘template<class _Alloc, class _Dummy, class ... _UElements, typename std::enable_if<((std::tuple<synchronizer>::_TMCT<_UElements ...>::_ConstructibleTuple<_UElements ...>() && std::tuple<synchronizer>::_TMCT<_UElements ...>::_ImplicitlyConvertibleTuple<_UElements ...>()) && std::tuple<synchronizer>::_TNTC<_Dummy>::_NonNestedTuple<const tuple<_Tail ...>&>()), bool>::type <anonymous> > std::tuple<_Elements>::tuple(std::allocator_arg_t, const _Alloc&, const std::tuple<_Args2 ...>&)’
763 | tuple(allocator_arg_t __tag, const _Alloc& __a,
| ^~~~~
/usr/include/c++/9/tuple:763:2: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: candidate expects 3 arguments, 1 provided
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:751:2: note: candidate: ‘template<class _Alloc> std::tuple<_Elements>::tuple(std::allocator_arg_t, const _Alloc&, std::tuple<_Elements>&&)’
751 | tuple(allocator_arg_t __tag, const _Alloc& __a, tuple&& __in)
| ^~~~~
/usr/include/c++/9/tuple:751:2: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: candidate expects 3 arguments, 1 provided
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:747:2: note: candidate: ‘template<class _Alloc> std::tuple<_Elements>::tuple(std::allocator_arg_t, const _Alloc&, const std::tuple<_Elements>&)’
747 | tuple(allocator_arg_t __tag, const _Alloc& __a, const tuple& __in)
| ^~~~~
/usr/include/c++/9/tuple:747:2: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: candidate expects 3 arguments, 1 provided
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:741:11: note: candidate: ‘template<class _Alloc, class ... _UElements, typename std::enable_if<(std::tuple<synchronizer>::_TMC<_UElements ...>::_MoveConstructibleTuple<_UElements ...>() && (! std::tuple<synchronizer>::_TMC<_UElements ...>::_ImplicitlyMoveConvertibleTuple<_UElements ...>())), bool>::type <anonymous> > std::tuple<_Elements>::tuple(std::allocator_arg_t, const _Alloc&, _UElements&& ...)’
741 | explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
| ^~~~~
/usr/include/c++/9/tuple:741:11: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: candidate expects at least 2 arguments, 1 provided
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:730:2: note: candidate: ‘template<class _Alloc, class ... _UElements, typename std::enable_if<(std::tuple<synchronizer>::_TMC<_UElements ...>::_MoveConstructibleTuple<_UElements ...>() && std::tuple<synchronizer>::_TMC<_UElements ...>::_ImplicitlyMoveConvertibleTuple<_UElements ...>()), bool>::type <anonymous> > std::tuple<_Elements>::tuple(std::allocator_arg_t, const _Alloc&, _UElements&& ...)’
730 | tuple(allocator_arg_t __tag, const _Alloc& __a,
| ^~~~~
/usr/include/c++/9/tuple:730:2: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: candidate expects at least 2 arguments, 1 provided
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:720:11: note: candidate: ‘template<class _Alloc, class _Dummy, typename std::enable_if<(std::tuple<synchronizer>::_TCC<_Dummy>::_ConstructibleTuple<synchronizer>() && (! std::tuple<synchronizer>::_TCC<_Dummy>::_ImplicitlyConvertibleTuple<synchronizer>())), bool>::type <anonymous> > std::tuple<_Elements>::tuple(std::allocator_arg_t, const _Alloc&, const _Elements& ...)’
720 | explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
| ^~~~~
/usr/include/c++/9/tuple:720:11: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: candidate expects 3 arguments, 1 provided
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:709:2: note: candidate: ‘template<class _Alloc, class _Dummy, typename std::enable_if<(std::tuple<synchronizer>::_TCC<_Dummy>::_ConstructibleTuple<synchronizer>() && std::tuple<synchronizer>::_TCC<_Dummy>::_ImplicitlyConvertibleTuple<synchronizer>()), bool>::type <anonymous> > std::tuple<_Elements>::tuple(std::allocator_arg_t, const _Alloc&, const _Elements& ...)’
709 | tuple(allocator_arg_t __tag, const _Alloc& __a,
| ^~~~~
/usr/include/c++/9/tuple:709:2: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: candidate expects 3 arguments, 1 provided
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:699:2: note: candidate: ‘template<class _Alloc> std::tuple<_Elements>::tuple(std::allocator_arg_t, const _Alloc&)’
699 | tuple(allocator_arg_t __tag, const _Alloc& __a)
| ^~~~~
/usr/include/c++/9/tuple:699:2: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: candidate expects 2 arguments, 1 provided
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:693:28: note: candidate: ‘template<class ... _UElements, class _Dummy, typename std::enable_if<((std::tuple<synchronizer>::_TMCT<_UElements ...>::_MoveConstructibleTuple<_UElements ...>() && (! std::tuple<synchronizer>::_TMCT<_UElements ...>::_ImplicitlyMoveConvertibleTuple<_UElements ...>())) && std::tuple<synchronizer>::_TNTC<_Dummy>::_NonNestedTuple<tuple<_Tps ...>&&>()), bool>::type <anonymous> > constexpr std::tuple<_Elements>::tuple(std::tuple<_Args1 ...>&&)’
693 | explicit constexpr tuple(tuple<_UElements...>&& __in)
| ^~~~~
/usr/include/c++/9/tuple:693:28: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: ‘synchronizer’ is not derived from ‘std::tuple<_Tps ...>’
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:682:19: note: candidate: ‘template<class ... _UElements, class _Dummy, typename std::enable_if<((std::tuple<synchronizer>::_TMCT<_UElements ...>::_MoveConstructibleTuple<_UElements ...>() && std::tuple<synchronizer>::_TMCT<_UElements ...>::_ImplicitlyMoveConvertibleTuple<_UElements ...>()) && std::tuple<synchronizer>::_TNTC<_Dummy>::_NonNestedTuple<tuple<_Tps ...>&&>()), bool>::type <anonymous> > constexpr std::tuple<_Elements>::tuple(std::tuple<_Args1 ...>&&)’
682 | constexpr tuple(tuple<_UElements...>&& __in)
| ^~~~~
/usr/include/c++/9/tuple:682:19: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: ‘synchronizer’ is not derived from ‘std::tuple<_Tps ...>’
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:670:28: note: candidate: ‘template<class ... _UElements, class _Dummy, typename std::enable_if<((std::tuple<synchronizer>::_TMCT<_UElements ...>::_ConstructibleTuple<_UElements ...>() && (! std::tuple<synchronizer>::_TMCT<_UElements ...>::_ImplicitlyConvertibleTuple<_UElements ...>())) && std::tuple<synchronizer>::_TNTC<_Dummy>::_NonNestedTuple<const tuple<_Tps ...>&>()), bool>::type <anonymous> > constexpr std::tuple<_Elements>::tuple(const std::tuple<_Args1 ...>&)’
670 | explicit constexpr tuple(const tuple<_UElements...>& __in)
| ^~~~~
/usr/include/c++/9/tuple:670:28: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: ‘synchronizer’ is not derived from ‘const std::tuple<_Tps ...>’
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:658:19: note: candidate: ‘template<class ... _UElements, class _Dummy, typename std::enable_if<((std::tuple<synchronizer>::_TMCT<_UElements ...>::_ConstructibleTuple<_UElements ...>() && std::tuple<synchronizer>::_TMCT<_UElements ...>::_ImplicitlyConvertibleTuple<_UElements ...>()) && std::tuple<synchronizer>::_TNTC<_Dummy>::_NonNestedTuple<const tuple<_Tps ...>&>()), bool>::type <anonymous> > constexpr std::tuple<_Elements>::tuple(const std::tuple<_Args1 ...>&)’
658 | constexpr tuple(const tuple<_UElements...>& __in)
| ^~~~~
/usr/include/c++/9/tuple:658:19: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: ‘synchronizer’ is not derived from ‘const std::tuple<_Tps ...>’
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:642:17: note: candidate: ‘constexpr std::tuple<_Elements>::tuple(std::tuple<_Elements>&&) [with _Elements = {synchronizer}]’
642 | constexpr tuple(tuple&&) = default;
| ^~~~~
/usr/include/c++/9/tuple:642:23: note: no known conversion for argument 1 from ‘synchronizer’ to ‘std::tuple<synchronizer>&&’
642 | constexpr tuple(tuple&&) = default;
| ^~~~~~~
/usr/include/c++/9/tuple:637:28: note: candidate: ‘template<class ... _UElements, typename std::enable_if<((std::tuple<synchronizer>::_TMC<_UElements ...>::_MoveConstructibleTuple<_UElements ...>() && (! std::tuple<synchronizer>::_TMC<_UElements ...>::_ImplicitlyMoveConvertibleTuple<_UElements ...>())) && (1 >= 1)), bool>::type <anonymous> > constexpr std::tuple<_Elements>::tuple(_UElements&& ...)’
637 | explicit constexpr tuple(_UElements&&... __elements)
| ^~~~~
/usr/include/c++/9/tuple:637:28: note: template argument deduction/substitution failed:
/usr/include/c++/9/tuple:636:21: error: no type named ‘type’ in ‘struct std::enable_if<false, bool>’
636 | bool>::type=false>
| ^~~~~
/usr/include/c++/9/tuple:626:19: note: candidate: ‘template<class ... _UElements, typename std::enable_if<((std::tuple<synchronizer>::_TMC<_UElements ...>::_MoveConstructibleTuple<_UElements ...>() && std::tuple<synchronizer>::_TMC<_UElements ...>::_ImplicitlyMoveConvertibleTuple<_UElements ...>()) && (1 >= 1)), bool>::type <anonymous> > constexpr std::tuple<_Elements>::tuple(_UElements&& ...)’
626 | constexpr tuple(_UElements&&... __elements)
| ^~~~~
/usr/include/c++/9/tuple:626:19: note: template argument deduction/substitution failed:
/usr/include/c++/9/tuple:625:21: error: no type named ‘type’ in ‘struct std::enable_if<false, bool>’
625 | bool>::type=true>
| ^~~~
/usr/include/c++/9/tuple:599:26: note: candidate: ‘template<class _Dummy, typename std::enable_if<((std::tuple<synchronizer>::_TCC<_Dummy>::_ConstructibleTuple<synchronizer>() && (! std::tuple<synchronizer>::_TCC<_Dummy>::_ImplicitlyConvertibleTuple<synchronizer>())) && (1 >= 1)), bool>::type <anonymous> > constexpr std::tuple<_Elements>::tuple(const _Elements& ...)’
599 | explicit constexpr tuple(const _Elements&... __elements)
| ^~~~~
/usr/include/c++/9/tuple:599:26: note: template argument deduction/substitution failed:
/usr/include/c++/9/tuple:598:28: error: no type named ‘type’ in ‘struct std::enable_if<false, bool>’
598 | bool>::type=false>
| ^~~~~
/usr/include/c++/9/tuple:588:19: note: candidate: ‘template<class _Dummy, typename std::enable_if<((std::tuple<synchronizer>::_TCC<_Dummy>::_ConstructibleTuple<synchronizer>() && std::tuple<synchronizer>::_TCC<_Dummy>::_ImplicitlyConvertibleTuple<synchronizer>()) && (1 >= 1)), bool>::type <anonymous> > constexpr std::tuple<_Elements>::tuple(const _Elements& ...)’
588 | constexpr tuple(const _Elements&... __elements)
| ^~~~~
/usr/include/c++/9/tuple:588:19: note: template argument deduction/substitution failed:
/usr/include/c++/9/tuple:587:28: error: no type named ‘type’ in ‘struct std::enable_if<false, bool>’
587 | bool>::type=true>
| ^~~~
/usr/include/c++/9/tuple:571:26: note: candidate: ‘template<class _Dummy, typename std::enable_if<(std::tuple<synchronizer>::_TC2<_Dummy>::_DefaultConstructibleTuple() && (! std::tuple<synchronizer>::_TC2<_Dummy>::_ImplicitlyDefaultConstructibleTuple())), bool>::type <anonymous> > constexpr std::tuple<_Elements>::tuple()’
571 | explicit constexpr tuple()
| ^~~~~
/usr/include/c++/9/tuple:571:26: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: candidate expects 0 arguments, 1 provided
267 | } };
| ^
In file included from /usr/include/c++/9/bits/unique_ptr.h:37,
from /usr/include/c++/9/memory:80,
from /usr/include/c++/9/thread:39,
from server.cpp:14:
/usr/include/c++/9/tuple:561:17: note: candidate: ‘template<class _Dummy, typename std::enable_if<std::tuple<synchronizer>::_TC2<_Dummy>::_ImplicitlyDefaultConstructibleTuple(), bool>::type <anonymous> > constexpr std::tuple<_Elements>::tuple()’
561 | constexpr tuple()
| ^~~~~
/usr/include/c++/9/tuple:561:17: note: template argument deduction/substitution failed:
In file included from server.cpp:14:
/usr/include/c++/9/thread:267:4: note: candidate expects 0 arguments, 1 provided
267 | } };
| ^
/usr/include/c++/9/thread:267:4: error: could not convert ‘{<expression error>}’ from ‘<brace-enclosed initializer list>’ to ‘std::thread::_Invoker<std::tuple<synchronizer> >’
