[Pierre-Marie Baty]

clock() does not return unsigned longs, hence the rollover is fixed to LONG_MAX and can't be changed. It's the RETURN TYPE of the clock() function which determines the rollover, not the capacity of the variable I put it in.

And in this function the type "double" was used only to provide a greater floating-point computation accuracy, but this extra precision is not needed in the return type, since converting the results to float do not truncate any data at all. The precision was only needed during the computations.