We need to use this version of z2d so that we can get reproducible PNG
exports in CI for testing, since previously the PNG export was affected
by the CPU arch / features because it depended on vector width.
Fixes#7724
Background at the end of the commit message. The fix in libxev is
described in the PR and commit we pin to here, but basically we swap
read for poll for eventfd/timerfd.
From Jens Axboe on X:
> This will fix it: https://pastebin.com/n7JSZWpW which makes me suspicious
> that it's an S_IFREG check somewhere else, as anon inodes are now listed as
> regular files. Has potentially pretty broad implications...
> I think I can already answer why that breaks things - io_uring checks if
> this is a regular file, and if it is, it doesn't do short reads. Short
> reads on regular files (or a bdev) will cause application issues, as
> basically nobody expects them.
> Now we have what acts like a char dev, but where io_uring will retry IO
> because the application asked for more data than what was delivered. This
> will cause the weird slowdowns as data isn't delivered as soon as it's
> available.
This updates our bundled Harfbuzz from 8.4 to 11.0. The changes from 8
to 11 include a number of correctness and performance improvements.
Packaged releases tend to dynamically link so this won't affect
existing users, but build-from-source users hopefully get an
improvement.
We have always tracked a post-3.4 release, this brings us up to date.
There's no real motivation beyond this other than keeping up to date
since we're already on non-release versions anyways.
Upstream is now mostly pure Zig and the build.zig.zon.* files are
generated directly by zon2nix. The JSON file is no longer used as an
intermediate file but is retained for downstream packager usage.
