No type named 'atomic' in namespace 'std'

Question

Why doesn't

std::atomic<int> index;

Work?

Currently using LLVM 3.1 with these params

C Language Dialect GNU [-std=gnu99]
C++ Language Dialect [-std=c++11]
C++ Standard Library libc++(LLVM C++ standard library with C++11 support)

Answer 1

There are several things that need to be true for your code to work:

1. You need to #include <atomic>

2. You need to compile the code as C++11 or C++14 (-std=c++11 or -std=c++14 (or c++0x for older compilers))

3. Your compiler and standard library needs to support enough of C++11 to provide atomic (http://clang.llvm.org/cxx_status.html)

Answer 2

Adding -std=c++11 to CXXFLAGS in my Makefile -> that works for me!

Answer 3

You need to write it as the following to defined variable.

    std::atomic<std::int> index;