Subject: Re: bug#65491: [PATCH] Improve performance allocating vectors

From: Mattias Engdegård <[email-masked]>
Date: Mon, 18 Sep 2023 18:10:47 +0200

17 sep. 2023 kl. 18.44 skrev Eli Zaretskii <[email-masked]>:

> Feel free to add any comments you find useful, that is always welcome.
> But comments about complicated code have one downside: they need to be
> updated when the code changes, and people forget to do that...

Eli and Paul, thank you very much. I'm reapplying the patches (that we now know shouldn't cause warnings), with added comments with respect to the vanishing subtrahend in -with-wide-int builds.

The conversion at the other end, TAG_PTR, suffers from the same potential problem but in reverse, which is perhaps less obvious to the casual C programmer but nevertheless a danger of the same kind, so we'd better do something about it as well. I'll be back with a proposed patch.