bug#62762: circular dependencies in elisp files and make

[Stefan Monnier]

> I do not see a reason for significant slow-down because I do not suggest two
> passes of *byte-compilataion*.

Not sure about two passes, but if you want it to be "right" (i.e. aim
to never need `make bootstrap`), then every `.elc` file will transitively
depend on every preloaded `.el` file, including `loaddefs.el` which is
itself auto-generated from all the `.el` files.  IOW the only truly
"right" way is to always recompile all the `.elc` files whenever  `.el`
(or `.c` or `.h`) file is modified :-(

So, in order to avoid this, we need to make concessions, such as
ignoring (transitive) dependencies on preloaded files, and those files
used by the byte compiler.


        Stefan