bug#18443: 24.3.93; Feature request - Add a variable for byte-compile function in `package--compile'

[Glenn Morris]

Stefan Monnier wrote:

>    E.g. we could add to bytecomp.el the ability to force `require' to
>    reload a package if it's not already loaded from the file that
>    locate-library returns.

This means this is the same issue as #10125. (The other suggestion was to
compile packages in a separate Emacs instance.)