I've just installed the latest version of cygwin and eclipse luna in my machine. It's working fine and I'm able to run my projects. However when I build them I got warnings I don't understand. For example, here are the warnings from a header file "Sales_item.h" which I got from the site of a book "c++ Primer":
warning: defaulted and deleted functions only available with -std=c++11 or -std=gnu++11 [enabled by default]
Sales_item() = default;
^
../src/Sales_item.h:70:27: warning: non-static data member initializers only available with -std=c++11 or -std=gnu++11 [enabled by default]
unsigned units_sold = 0; // explicitly initialized
^
../src/Sales_item.h:71:22: warning: non-static data member initializers only available with -std=c++11 or -std=gnu++11 [enabled by default]
double revenue = 0.0;
^
Finished building: ..
What do these warnings mean? Should I do something?