Errors while switching to stock toolchain

[porterchild]

While switching from the 0.12 S4TF release to a stock toolchain from https://swift.org/download/#releases, I've gotten some compiler errors.

1. When extending Optional and using TangentVector, the compiler says 'TangentVector' is not a member type of 'Optional'. This surprises me. Am I missing something?
2. When using the KeyPathIterable implementation from swift-apis, I get the error "Cannot find '_forEachFieldWithKeyPath' in scope ", which I thought would be fixed by this PR. I've made sure to use @_spi(Reflection) to import the special function.

Any help would be appreciated.

[dan-zheng]

Hi Porter,

Thanks for reporting. Could you please share the stock toolchain that you've downloaded?

[porterchild]

Sure it's the Tag: swift-5.3.3-RELEASE

[dan-zheng]

Sure it's the Tag: swift-5.3.3-RELEASE

Could you try a trunk development snapshot instead? Those are tested in the "stock toolchain" migration PRs, be sure to follow the build instructions in the PR descriptions:

• tensorflow/swift-models: tensorflow/swift-apis as SwiftPM dependency
• borglab/SwiftFusion: tensorflow/swift-apis as SwiftPM dependency

Trunk development snapshots are built from apple/swift:main branch, similar to the old Swift for TensorFlow toolchains. Release toolchains are built from release branches and often are missing recent changes related to differentiable programming.

[porterchild]

Thanks Dan, that fixed it!

[porterchild]

I'm going to miss asking you obvious questions

[dan-zheng]

I'm going to miss asking you obvious questions

I'm still around! Feel free to ping or email me anytime :)

[porterchild]

Cool! Glad to know you'll still be around I like TabNine

[porterchild]

Many errors later :) , I have a few more questions:

1. It seems like a lot of AdditiveArithmetic, KeyPathIterable, PointwiseMultiplicative.. etc. automatic synthesis is gone. I've pulled just the protocols I need from swift-apis, and I'm importing Numerics for ElementaryFunctions. I'd like to understand if I'm just missing bringing some code over from swift-apis or Numerics, or if automatic synthesis has changed since the 0.12 release compared to the latest swift mainline. I've had to write a lot more conformances manually compared to the 0.12 release.
2. SIMDX<Float>.sum() is no longer automatically differentiable, I'm not sure why. I see no mention of it in swift-apis.

For context, I'm on the 1/14 snapshot (the latest snapshot has a new compiler crash

[porterchild]

Ah, I just found the comment // FIXME(TF-1103): Derivative registration does not yet support @_alwaysEmitIntoClient original functions like SIMD.sum() at https://github.com/apple/swift/blob/e3db926e0ce7bb5535e357623b8744c2c276b236/stdlib/public/Differentiation/SIMDDifferentiation.swift.gyb. So that explains why SIMDX<Float>.sum() isn't differentiable.