Disallow inline arrays with explicit size #117578
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Pull Request Overview
This PR disallows inline arrays annotated with an explicit size by enforcing runtime checks and updating related resources and tests.
- Added new loader IL and C# tests for explicit-size inline arrays
- Implemented explicit-size checks in both Mono (
class-init.c) and CoreCLR (methodtablebuilder.cpp,MetadataFieldLayoutAlgorithm.cs) - Introduced new resource strings and exception IDs for inline-array explicit-size errors
Reviewed Changes
Copilot reviewed 12 out of 12 changed files in this pull request and generated 2 comments.
Show a summary per file
| File | Description |
|---|---|
| src/tests/Loader/classloader/InlineArray/InvalidCSharpInlineArray.il | Added IL test for explicit-size inline array |
| src/tests/Loader/classloader/InlineArray/InlineArrayInvalid.csproj | Set test priority for invalid inline array tests |
| src/tests/Loader/classloader/InlineArray/InlineArrayInvalid.cs | Added ExplicitSize_Fails Xunit test |
| src/mono/mono/metadata/class-init.c | Added explicit-size inline-array failure callback |
| src/libraries/System.Private.CoreLib/src/Resources/Strings.resx | Added resource string for explicit-size inline-array error |
| src/coreclr/vm/methodtablebuilder.cpp | Throw exception for explicit-size inline-array in method table |
| src/coreclr/tools/Common/TypeSystem/Common/Properties/Resources.resx | Added resource for type-system inline-array explicit-size |
| src/coreclr/tools/Common/TypeSystem/Common/MetadataFieldLayoutAlgorithm.cs | Checked for explicit-size inline-array during layout computation |
| src/coreclr/tools/Common/TypeSystem/Common/ExceptionStringID.cs | Added exception string ID for inline-array explicit-size |
| src/coreclr/nativeaot/System.Private.CoreLib/src/Internal/Runtime/TypeLoaderExceptionHelper.cs | Mapped TypeSystem exception to resource string |
| src/coreclr/dlls/mscorrc/resource.h | Defined new resource ID for explicit-size inline-array error |
| src/coreclr/dlls/mscorrc/mscorrc.rc | Added message text for explicit-size inline-array error |
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Does this need to be marked as a breaking change? |
This can break some existing program (if such exist), so technically yes. |
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Added When you commit this breaking change:
Tagging @dotnet/compat for awareness of the breaking change. |
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/ba-g cryptography failures on musl, wasm timing out |
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Thanks! |
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Breaking change issue - dotnet/docs#47435 |
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Removing |
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Fixes: #110962
Specifying
.sizeon an InlineArray struct only brings confusion to whether it applies to the element or to thr entire instance. It Either result is a fairly niche scenario and can be achieved via defining wrapping structs.Notes:
.sizeis disallowed in eithersequentialorautolayouts..packis allowed. Unlike.size, there is no ambiguity with.pack- it has no effect in structs with all fields having the same type, regardless of 1 or N fields.