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c++c++11cygwin

Does gcc 4.7.3 on cygwin support C++11 concurrency features?

I am trying to compile the following program on a 64 bit Windows 7 machine with cygwin installed and the gcc compiler updated to 4.7.3:

#include <vector>
#include <thread>
#include <mutex>

using namespace std;

std::mutex flemutex;
std::mutex arrmutex;

main() {

thread t;
}

On compiling with the following command:

 gcc -std=c++11 -o file.o -c file.cpp

I get the following errors:

file.cpp:12:1: error: ‘mutex’ in namespace ‘std’ does not name a type
file.cpp:13:1: error: ‘mutex’ in namespace ‘std’ does not name a type
file.cpp: In function ‘int main()’:
file.cpp:39:3: error: ‘thread’ is not a member of ‘std’
file.cpp:39:15: error: expected ‘;’ before ‘t’

Does anyone know whats going on?

Thanks!

Solution

  • You can try the following:

    #include <thread>
#include <iostream>

using std::cout;
using std::endl;

main() {
#ifndef(_GLIBCXX_HAS_GTHREADS)
  cout << "GThreads are not supported..." << endl;
#endif
}

    In fact, as of GCC 4.4, _GLIBCXX_HAS_GTHREADS is undefined when libstdc++ is built because Cygwin implementation of pthread lacks some functionality. The same was true for MinGW.

    NOTE: GThreads, which is directly used by std::thread, is a GCC wrapper around POSIX threads.

    There are builds of MinGW-w64 based on GCC 4.7 and 4.8 targeting both 64-bit and 32-bit, which offer experimental support for std::thread. Furthermore, yes, of course Cygwin and MinGW can co-exist as long as you switch between these 2 environments correctly, i.e. do not mix them in the PATH environment variable.

    Relevant links: