Why does this simple std::thread example not work?

Question

Tried the following example compiled with g++ -std=gnu++0x t1.cpp and g++ -std=c++0x t1.cpp but both of these result in the example aborting.

$ ./a.out  terminate called after throwing an instance of 'std::system_error'   what():   Aborted 

Here is the sample:

#include <thread> #include <iostream>  void doSomeWork( void ) {     std::cout << "hello from thread..." << std::endl;     return; }  int main( int argc, char *argv[] ) {     std::thread t( doSomeWork );     t.join();     return 0; } 

I'm trying this on Ubuntu 11.04:

$ g++ --version g++ (Ubuntu/Linaro 4.5.2-8ubuntu4) 4.5.2 

Anyone knows what I've missed?

Answer 1

You have to join std::threads, just like you have to join pthreads.

int main( int argc, char *argv[] ) {     std::thread t( doSomeWork );     t.join();     return 0; } 

UPDATE: This Debian bug report pointed me to the solution: add -pthread to your commandline. This is most probably a workaround until the std::thread code stabilizes and g++ pulls that library in when it should (or always, for C++).

Answer 2

Please use the pthread library during the compilation: g++ -lpthread.