Prior to this change, in floating-point computations, in the case
where we work for types where std::numeric_limits are not specialized,
funcitons min() and max() from std::numeric_limits<FPT> are nonetheless
instantiated and return FPT(0). While the result is never used in run-time,
this may still trigger a compile-time failure.
After this change, the paths for the cases where std::numeric_limits are not
specialized are handled by separate specializations rather than run-time if
statements.
817ac936c9