Re: Byte compiler inefficiency

[Richard M. Stallman]

    > When cadr is called interpretively, the binding of x is like any
    > other binding.

    Sure, but the binding can't possible have any effect on the result.

In the particular case of cadr, it can't, because no non-primitive
functions are called.  If the compiler could detect this kind of case,
it could do the optimization safely.

However, if the defsubst calls some non-primitives, they could refer
to the variable, so failing to bind it would be unsafe.

Implementing the optimization in the former case would be useful,
and I will put it in etc/TODO, but it should not be done until
after the release.