Rob NapierJun 6, 2023

I was really hoping that Xcode 15 would include some incremental build performance improvements, but I'm not seeing any so far. SWIFT_USE_INTEGRATED_DRIVER=NO is still 2-3 times faster. ~20s to recompile a one-line change, which isn't great, but it's workable. With the integrated driver, it's about 1m for every build, not counting getting it onto the sim/device, etc.

Worse, AppIntents extraction is now more aggressive, and adds an extra 70s even if AppIntents is not linked. FB12215849

Show threadRob NapierJun 6, 2023

It looks like "Extract App Intents metadata" is happening in Xcode 15 even if you don't link the AppIntents framework. This can add significant time to every build, including incremental builds (in our project, ~70s). FB12246243

The build setting LM_ENABLE_LINK_GENERATION=NO disables App Intent extraction entirely. I don't believe this is documented anywhere; I reverse engineered it from Xcode.

Show threadAgis TsarampoulidisMar 13
@cocoaphony 👋 Did they manage to address that or your fix is still the fix? Dealing with the exact same issue.
Show threadRob NapierMar 13
@agis Apple marked this FB "Potential fix identified - In Xcode 15." They never actually responded to this FB, so I don't know precisely what that means. We do not currently set SWIFT_USE_INTEGRATED_DRIVER or LM_ENABLE_LINK_GENERATION, so I expect it was fixed.
Show threadAgis TsarampoulidisMar 13
@cocoaphony interesting because I experience the exact opposite do you remember how can this be applied to swift packages?
Show threadRob NapierMar 13
@agis I'm not sure what you mean here. Are you talking about the fact that incremental builds are slow? (Yes, they're still pretty slow, though we do not disable the integrated driver any more.) Or do you mean that AppIntents is running when not expected and very slow? (That may be fixed.)
Show threadAgis Tsarampoulidis
@cocoaphony LM_ENABLE_LINK_GENERATION=NO
improves build time in my testing and the other part was how this can be applied to swift packages. I still see app intents running for swift packages.
Mar 13 at 6:16pmIvory for iOS
Show threadRob NapierMar 13
@agis We don't currently use that flag (we require AppIntents currently). I don't have any more information since the original post.