Does MinGW-w64 support std::thread out of the box when using the Win32 threading model?

c++ multithreading c++11 gcc mingw-w64
Marc.2377 picture Marc.2377 · May 21, 2016 · Viewed 17.7k times · Source

I have opted for the Win32 threading model when installing the MinGW-w64 toolchain, after reading that it provides better performance than the POSIX counterpart. I am not qualified for benchmarking this claim myself, but here's a source for it.

At first I thought this option would only affect the inner workings of the GCC runtime, while not preventing me from using C++11 threads in my code, based on this answer and this comment by fellow user rubenvb.
However, this doesn't seem to be the case. std::thread support appears to be non-existent in this MinGW-w64 installation.

I am invoking g++ from the command line with no options other than -std=c++11.

At this point I'm not sure if:

  • rubenvb was mistaken, and it's actually necessary to install MinGW-w64 under the POSIX threading model in order to compile my code which depends on the C++11 thread library, or;
  • I completely misunderstood it all, or;
  • std::thread is actually supported in my scenario, it's just not intuitive.

I reinforce the "out of the box" part in the title. There exists a library called mingw-std-threads, as presented in this answer. However, as a third-party option, it is not relevant to this question.

So, as of today (May 2016), does MinGW-w64 nativelly support std::thread depending code, when installed with the Win32 internal threading model?

Answer

M.M picture M.M · May 21, 2016

To use the MinGW-w64 with Win32 native threads you can install the mingw-std-threads headers.

As described on that page, this is because MinGW-w64 is a port of GCC, but GCC does not include any native thread support. Instead GCC installations typically implement threading via either gthreads or pthreads as a part of glibc. MinGW-w64 does not include a port of glibc. (Instead it uses a combination of the MSVC runtime, plus its own code to fill in holes).

Also as described on that page, recent versions of MinGW-w64 do include a Win32 port of pthreads ("winpthreads"), which explains why you can have threads work "out of the box" by selecting the "pthread" model from the MinGW-w64 installer.

Related questions

Start thread with member function

I am trying to construct a std::thread with a member function that takes no arguments and returns void. I can't figure out any syntax that works - the compiler complains no matter what. What is the correct way to …

Read More
C++11 introduced a standardized memory model. What does it mean? And how is it going to affect C++ programming?

C++11 introduced a standardized memory model, but what exactly does that mean? And how is it going to affect C++ programming? This article (by Gavin Clarke who quotes Herb Sutter) says that, The memory model means that C++ code now …

Read More
Thread pooling in C++11

Relevant questions: About C++11: C++11: std::thread pooled? Will async(launch::async) in C++11 make thread pools obsolete for avoiding expensive thread creation? About Boost: C++ boost thread reusing threads boost::thread and creating a pool of them! How do …

Read More