multithreading - Can not start threads from pointer to function, C++ -

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i trying start thread execution doing following:

 #include <thread>  #include <stdio.h>   typedef void (*callback_function)(void);   void printer(){      printf("something\n");  }   void dotask(callback_function a){      std::thread t1(a);  }   int main(){      callback_function print = printer;      dotask(print);  }

executing piece of code, result core dumped. surprisingly, when change function dotask one:

void dotask(callback_function a){      a(); }

it works, or doing works:

int main(){      callback_function print = printer;      std::thread t1(printer); }

does knows i'm missing or doing wrong?

both cases wrong. object std::thread t1 lives until function dotask exits. thread object trying destroying while callback_function still works.
should wait thread stop it's work , delete it.

int main(){     callback_function print = printer;     std::thread t1(printer);     // other stuff     t1.join(); }

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