Why did iOS 26 break just in time compilation
Asked on 06/11/2025
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The context provided does not specifically mention why iOS 26 might have broken just-in-time (JIT) compilation. However, there are several discussions around improvements and changes in Swift and Xcode, such as the introduction of explicitly built modules and enhancements in Swift's build system, which could potentially impact how code is compiled and executed. These changes might indirectly affect JIT compilation if they alter the way code is processed or executed at runtime.
For more detailed information, you might want to explore sessions related to Swift and Xcode, such as:
- What’s new in Xcode (Builds)
- What’s new in Swift (Development workflow: Building)
- Demystify explicitly built modules (Using modules)
These sessions discuss changes in the build process and module handling, which could be relevant to understanding any issues with JIT compilation.

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