Use a class constructor to initialize CPU cache sizes
Use a class constructor to initialize CPU cache sizes

Using a static instance of a class to initialize the values for
the CPU cache sizes guarantees thread-safe initialization of the
values when using C++11. Therefore under C++11 it is no longer
necessary to call Eigen::initParallel() before calling any eigen
functions on different threads.

pthulhu/eigen,pthulhu/eigen,pthulhu/eigen,pthulhu/eigen,pthulhu/eigen