Re: byte compiler warnings for different Emacs versions

[Stefan Monnier]

> [Note: If the opposite test is made (conditionalize code for >= 21 and
> byte-compile in Emacs 20), no such warnings are issued, so this changed
> behavior is presumably a useful feature.]

The Emacs-20 byte-compiler simply doesn't have this warning at all, which is
why it won't say anything.  The condition in the `when' has nothing to do
with what you're seeing.

If a file byte-compiled on Emacs-20 doesn't run on Emacs-21 it's generally
considered as a bug (but not the other way around).


        Stefan