mlx-swift 0.30.2 pin fails to build with Xcode 26 / iOS 26 SDK

[benkruger]

Problem

kokoro-ios pins mlx-swift to exact: "0.30.2" in Package.swift. This version has undefined symbols when building against the iOS 26.2 SDK (Xcode 26):

Undefined symbols for architecture arm64:
  "_MTLIOErrorDomain", referenced from:
      ___cxx_global_var_init.3775 in device-....o
  "_MTLTensorDomain", referenced from:
      ___cxx_global_var_init.3746 in device-....o
ld: symbol(s) not found for architecture arm64

Fix

This was fixed in mlx-swift 0.30.6 via ml-explore/mlx-swift#354 ("Weakly link error domains to allow building non-Metal-supporting targets").

Bumping the pin from exact: "0.30.2" to exact: "0.30.6" (or from: "0.30.6") resolves the build failure.

Secondary issue

The resource path .copy("../../Resources/") in Package.swift creates resource bundles that fail codesign when consumed as a remote SPM dependency:

KokoroSwift_KokoroSwift.bundle: bundle format unrecognized, invalid, or unsuitable

Environment

• Xcode 26.2 (Swift 6.2.4)
• iOS Simulator 26.2 SDK
• Apple Silicon (arm64)

[SanitizedMemory]

We reproduce the same missing MTLIOErrorDomain and MTLTensorDomain symbols with Kokoro 1.0.11 and the pinned mlx-swift 0.30.2 when building our iOS 27-only app against Xcode 27 beta 4 and the iOS 27 Simulator SDK.

Our temporary host-side mitigation supplies Simulator-only error-domain definitions so deterministic tests can compile; live Kokoro synthesis remains unavailable on Simulator and physical iPhone builds use Metal native definitions. We are tracking removal at https://github.com/SanitizedMemory/financial-app/issues/412.

Can maintainers confirm whether updating the Kokoro package pin to the MLX version containing ml-explore/mlx-swift#354 is the intended fix for current Xcode 27 SDKs as well?