Stream: bugs

Topic: ✔ Slowdown in LLVM


view this post on Zulip Karl (Sep 18 2026 at 15:52):

I bump the Roc compiler on Thursdays unless there's a bug that gets closed and yesterday's bump is taking my UI builds from 18s to 80s. Claude claims the cause is LLVM inlining a 2.9k llines 14 times in a function and subsequent passes having trouble with a 200k+ function body.

Are other people running into this?

view this post on Zulip Anton (Sep 18 2026 at 15:56):

I have not seen it, today's nightly is published, feel free to give that a try and open an issue if it is still a problem.

view this post on Zulip Matthieu Pizenberg (Sep 18 2026 at 16:12):

I filed issues related to inlining (as in, big runtime slowdown due to not inlining), fixed by Richard. But that was at least a few weeks ago, so probably not relevant.

view this post on Zulip Notification Bot (Sep 18 2026 at 18:03):

Karl has marked this topic as resolved.

view this post on Zulip Richard Feldman (Sep 18 2026 at 18:28):

@Karl how did this end up getting resolved for you? Did updating to latest main fix it?

view this post on Zulip Karl (Sep 18 2026 at 18:30):

I marked it resolved because I filed an issue and didn't want to have the discussion in two places. My app just happened to slip through the gap in your inlining change from last week. I'm on an older build in the meantime.


Last updated: Sep 24 2026 at 15:59 UTC