In function `_start': : undefined reference to `main' collect2: ld returned 1 exit status make: *** [test_data] Error 1

Error Output:

```
/builds/zhigalin.da/spbspu-labs-2018/testxFJ3vQ87/templates/A1.cpp: In 
function 'int main()':
/builds/zhigalin.da/spbspu-labs-2018/testxFJ3vQ87/templates/A1.cpp:11:40: 
error: 'x' is not a member of 'point_t'
static_assert(std::is_same< decltype(point_t::x), double >::value,
                                    ^~~~~~~
/builds/zhigalin.da/spbspu-labs-2018/testxFJ3vQ87/templates/A1.cpp:11:40:       
error: 'x' is not a member of 'point_t'
/builds/zhigalin.da/spbspu-labs-2018/testxFJ3vQ87/templates/A1.cpp:11:60: 
error: template argument 1 is invalid
static_assert(std::is_same< decltype(point_t::x), double >::value,
                                                        ^
/builds/zhigalin.da/spbspu-labs-2018/testxFJ3vQ87/templates/A1.cpp:13:40: 
error: 'y' is not a member of 'point_t'
static_assert(std::is_same< decltype(point_t::y), double >::value,
                                    ^~~~~~~

if i testing project in terminal i get this error: