aot-trimming

1# .NET Trimming and Native AOT
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3## When to Use
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5- Adding trimming (`PublishTrimmed`) or Native AOT (`PublishAot`) support to a library or application
6- Resolving `IL2xxx` (trimming) and `IL3xxx` (AOT/single-file) warnings
7- Making reflection-heavy code trimming-safe
8- Replacing runtime reflection, assembly scanning, or `Reflection.Emit` with compile-time alternatives
9- Reviewing a codebase or PR for trimming/AOT compatibility, including generated interceptors and analyzer suppressors
10- Designing public APIs that must carry trimming annotations
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12## Core Goals
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14- Produce code that survives the linker's reachability analysis and runs under Native AOT (no JIT).
15- Express what the compiler cannot see — which members reflection needs — using the trimming attributes.
16- Keep trimming-safe and trimming-unsafe code separated so unsafe paths are explicit and contained.
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18## Core Model
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20### Trimming vs Native AOT
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22- **Trimming** (`PublishTrimmed`) runs ILLink reachability analysis: only statically reachable code is kept. Reflection the analyzer cannot see is trimmed away and produces warnings.
23- **Native AOT** (`PublishAot`) makes trimming mandatory and removes the JIT. `Reflection.Emit` is unsupported, constructing *unknown* generic instantiations at runtime is not guaranteed, `Expression.Compile()` may fall back to interpretation, and reflection works only over members the linker preserved.
24- Both run the same static analysis:
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