/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x4fd): undefined reference to `std::thread::_State::~_State()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x53d): undefined reference to `std::thread::_State::~_State()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x57d): undefined reference to `std::thread::_State::~_State()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x5bd): undefined reference to `std::thread::_State::~_State()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xa5f): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xa7e): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xb1f): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xb3e): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xbdf): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xbfe): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xc9e): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xcbc): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xd5e): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xd7c): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xe1e): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xe3c): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xede): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xefc): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xf9e): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0xfbc): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x105e): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x107c): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x112e): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x115b): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1184): undefined reference to `std::thread::join()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x121e): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x124b): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1274): undefined reference to `std::thread::join()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x130e): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x133b): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1364): undefined reference to `std::thread::join()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x13fd): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1428): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1454): undefined reference to `std::thread::join()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x14ed): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1518): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1544): undefined reference to `std::thread::join()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x15dd): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1608): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1634): undefined reference to `std::thread::join()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x16cd): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x16f8): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1734): undefined reference to `std::thread::join()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x17bd): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x17e8): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1824): undefined reference to `std::thread::join()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x18ad): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x18d8): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1914): undefined reference to `std::thread::join()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x19aa): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x19c8): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1a8b): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1aaa): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1b6a): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1b88): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1c5a): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1c87): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1cb4): undefined reference to `std::thread::join()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1d69): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1d94): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1dbc): undefined reference to `std::thread::join()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1e69): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1e94): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x1ecc): undefined reference to `std::thread::join()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x233e): undefined reference to `std::condition_variable::wait(std::unique_lock<std::mutex>&)'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x23a6): undefined reference to `std::condition_variable::wait(std::unique_lock<std::mutex>&)'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x3115): undefined reference to `std::condition_variable::condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x314a): undefined reference to `std::__future_base::_Result_base::_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x31d8): undefined reference to `std::thread::_M_start_thread(std::unique_ptr<std::thread::_State, std::default_delete<std::thread::_State> >, void (*)())'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x3352): undefined reference to `std::condition_variable::condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x3387): undefined reference to `std::__future_base::_Result_base::_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x3412): undefined reference to `std::thread::_M_start_thread(std::unique_ptr<std::thread::_State, std::default_delete<std::thread::_State> >, void (*)())'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x36e5): undefined reference to `std::condition_variable::condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x371c): undefined reference to `std::__future_base::_Result_base::_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x380c): undefined reference to `std::thread::_M_start_thread(std::unique_ptr<std::thread::_State, std::default_delete<std::thread::_State> >, void (*)())'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x3a45): undefined reference to `std::condition_variable::condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x3a7a): undefined reference to `std::__future_base::_Result_base::_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x3b08): undefined reference to `std::thread::_M_start_thread(std::unique_ptr<std::thread::_State, std::default_delete<std::thread::_State> >, void (*)())'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x42ea): undefined reference to `std::condition_variable::notify_all()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x43e2): undefined reference to `std::condition_variable::notify_all()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x44c2): undefined reference to `std::condition_variable::notify_all()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x45a2): undefined reference to `std::condition_variable::notify_all()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x4682): undefined reference to `std::condition_variable::notify_all()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x474a): more undefined references to `std::condition_variable::notify_all()' follow
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x4e7): undefined reference to `std::thread::_State::~_State()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x527): undefined reference to `std::thread::_State::~_State()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x567): undefined reference to `std::thread::_State::~_State()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text+0x5a7): undefined reference to `std::thread::_State::~_State()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZNSt13__future_base7_ResultI27CertificateValidationStatusED1Ev[__ZNSt13__future_base7_ResultI27CertificateValidationStatusED1Ev]+0x7): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZNSt13__future_base7_ResultI27CertificateValidationStatusED0Ev[__ZNSt13__future_base7_ResultI27CertificateValidationStatusED0Ev]+0xd): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZNSt13__future_base7_ResultI27CertificateValidationStatusE10_M_destroyEv[__ZNSt13__future_base7_ResultI27CertificateValidationStatusE10_M_destroyEv]+0x19): undefined reference to `std::__future_base::_Result_base::~_Result_base()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZNSt13__future_base13_State_baseV2D1Ev[__ZNSt13__future_base13_State_baseV2D1Ev]+0x11): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZNSt13__future_base13_State_baseV2D0Ev[__ZNSt13__future_base13_State_baseV2D0Ev]+0x11): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZNSt13__future_base21_Async_state_commonV2D1Ev[__ZNSt13__future_base21_Async_state_commonV2D1Ev]+0x1d): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZNSt13__future_base21_Async_state_commonV2D0Ev[__ZNSt13__future_base21_Async_state_commonV2D0Ev]+0x1d): undefined reference to `std::condition_variable::~condition_variable()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_]+0x5): undefined reference to `std::__get_once_mutex()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_]+0x6b): undefined reference to `std::__once_functor'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_]+0x71): undefined reference to `std::__once_functor'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_]+0x77): undefined reference to `std::__once_functor'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_]+0x80): undefined reference to `std::__once_functor'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_]+0x8a): undefined reference to `std::__once_functor'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_]+0x90): more undefined references to `std::__once_functor' follow
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_]+0xd1): undefined reference to `std::__set_once_functor_lock_ptr(std::unique_lock<std::mutex>*)'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_]+0xdd): undefined reference to `__once_proxy'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMNSt13__future_base13_State_baseV2EFvPSt8functionIFSt10unique_ptrINS0_12_Result_baseENS4_8_DeleterEEvEEPbEJPS1_S9_SA_EEvRSt9once_flagOT_DpOT0_]+0x108): undefined reference to `std::__set_once_functor_lock_ptr(std::unique_lock<std::mutex>*)'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_]+0x5): undefined reference to `std::__get_once_mutex()'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_]+0x30): undefined reference to `std::__once_functor'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_]+0x4a): undefined reference to `std::__once_functor'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_]+0x5c): undefined reference to `std::__once_functor'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_]+0x61): undefined reference to `std::__once_functor'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_]+0x67): undefined reference to `std::__once_functor'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_]+0x6d): more undefined references to `std::__once_functor' follow
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_]+0xae): undefined reference to `std::__set_once_functor_lock_ptr(std::unique_lock<std::mutex>*)'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_]+0xba): undefined reference to `__once_proxy'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_[__ZSt9call_onceIMSt6threadFvvEJPS0_EEvRSt9once_flagOT_DpOT0_]+0xe8): undefined reference to `std::__set_once_functor_lock_ptr(std::unique_lock<std::mutex>*)'
/usr/bin/i686-w64-mingw32-ld: CMakeFiles/poppler.dir/objects.a(GPGMECryptoSignBackend.cc.obj):GPGMECryptoSignBackend.cc:(.text$_ZNSt13__future_base21_Async_state_commonV217_M_complete_asyncEv[__ZNSt13__future_base21_Async_state_commonV217_M_complete_asyncEv]+0x24): undefined reference to `std::thread::join()'
collect2: error: ld returned 1 exit status
And in the linklibs.rsp there is also -lpthread listed: