>> > Using the jobserver directly would require quite a bit of work for the
>> > current patch set, but I wonder if there is another way to determine
>> > the -jN parameter for make<4.2 that we could use.  Maybe simply
>> > polling the jobserver fds at the start?  
>> 
>> AIUI the job server does not reveal how many jobs are allowed.  It
>> merely grants you an execution token.
>> 
>> Or did you have something else in mind?
>
> The idea (hardely tested) would be to read tokens from the input fd
> until it blocks, do the scheme compiles with however many tokens were
> read, then write them back out.  Crude, I guess, and probably error
> prone; compile-all.scm could be invoked when make has job tokens tied
> up building the daemon source...
>
> Anyhow, the current patch works well for me with a recent make.  I'm
> content leaving further improvements to a future hypothetical hacker. :)

Sounds reasonable.  Let’s make sure the hypothetical hacker has enough
on their plate.  :-)

I’ve pushed this and the easy parts of this patch series, with commit
d298c815e638581d466222f3a883b280f019b368 as the tip.

Thanks for the review!

Ludo’.