Summary:
Including `iostream` in a header causes anything that uses this header to gain
an extra static initializer for an `std::ios_base::Init` object.
If there are N translation units in a library that use the header, that's N
more static initializers that need to run.
Reviewed By: yfeldblum
Differential Revision:
D4191798
fbshipit-source-id:
65b47401b9177177999cff65a47ac8dffa0e0546
#include <atomic>
#include <boost/noncopyable.hpp>
-#include <iostream>
#include <cmath>
#include <memory>
#include <string.h>