[Bug c++/64318] Using _Cilk_for with <random> cause strange floating point exception

[zhouyan at me dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64318

--- Comment #4 from zhouyan at me dot com ---
The new example can be unsafe, if the constructor of the two classes are
unsafe. However, I went through the source of <random> before (during 4.8, 4.9
release), unless something changed, it's not the case.