Re: Has eval-and-compile changed in emacs 27?

[Stefan Monnier]

>> No, it was new back when we added the "not known to exist at run-time",
>> i.e. a long time ago.
> But the erldoc.el has been compiling without warnings since 24.5 and it
> suddenly changes in 27.

That's apparently a consequence of auth-source (`require`d by
`url-parse`) now `require`ing `json`.

>> We found it useful to try and warn the users when they did
>> (eval-when-compile (require FOO)) but FOO was also needed at run time.
> But it's been suggesting cl-reduce, cl-mapcan not defined at runtime
> when I explicitly have (require 'cl-lib) in the file which seems
> contradictory.

Yes, obviously the technique currently used doesn't always get it right.
Patches welcome ;-)


        Stefan