Most curiously while making unittests the asserts fail when I've confirmed it's working. The difference seems to be if it's immutable/const vs non, and why this makes a difference I don't see... Can someone give some light to this? const float i_f = 3.14159265; float a = i_f; float b = i_f; assert(a==b); //passes assert(a==i_f); //fails