Subject: bug#36447: 27.0.50; New "Unknown keyword" errors

From: Pip Cet <[email-masked]>
Date: Tue, 9 Jul 2019 14:00:50 +0000

On Mon, Jul 8, 2019 at 10:25 PM Noam Postavsky <[email-masked]> wrote:
> I've switched byte-compile-cond-use-jump-table to nil for now, so you
> shouldn't be hitting this anymore.

Thanks.

> > I know nothing about this, but did anybody want to fix this in a
> > different way, or did the discussion just peter our?
>
> There were some suggestions about checking PURE_P or similar to see if
> the copy is really needed, but then apparently PURE_P doesn't work at
> all?  I've been meaning to check that out, because it seems like there
> are still a few things which aren't making sense.

It does seem like we've effectively given up pure space when we
switched to pdumper. We still fill it and spend a lot of time making
sure not to waste any, but it's then simply copied to the dump along
with the rest of the dumped image. It's still kept around in the final
executable, so we're wasting quite a bit of disk space on it...

Most importantly, I think, the CHECK_IMPURE macro now does nothing
(except waste a few cycles), and we can freely setcar what should be
purecopied conses.

(One thing we might do is introduce immutable conses, and use them for
`read', pure space, and in a few other places).