Fix AttributeUsage.AllowMultiple not inherited for C#-defined attributes#19315
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This is ready! |
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This is good now, thanks for the fix!
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Commenter does not have sufficient privileges for PR 19315 in repo dotnet/fsharp |
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@T-Gro this is ready!! |
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@T-Gro Closing this PR. I do not have much time to keep fixing merge conflicts . Feel free to pick the changes if needed. Thanks |
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@edgarfgp , ok, let me try resolving them 👍 |
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…tes (#17107) The F# compiler was not walking the inheritance chain for IL-imported (C#) attribute types when checking AllowMultiple. The supersOfTyconRef function only used tcaug_super, which is not populated for IL types. This fix simplifies TryFindAttributeUsageAttribute to only check the current type, and adds a recursive allowsMultiple function in PostInferenceChecks that walks the inheritance chain using GetSuperTypeOfType, which correctly handles both F# and IL-imported types. Based on work by edgarfgp in PR #19315. Fixes #17107 Co-authored-by: edgarfgp <31915729+edgarfgp@users.noreply.github.com> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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…tes (dotnet#17107) The F# compiler was not walking the inheritance chain for IL-imported (C#) attribute types when checking AllowMultiple. The supersOfTyconRef function only used tcaug_super, which is not populated for IL types. This fix simplifies TryFindAttributeUsageAttribute to only check the current type, and adds a recursive allowsMultiple function in PostInferenceChecks that walks the inheritance chain using GetSuperTypeOfType, which correctly handles both F# and IL-imported types. Based on work by edgarfgp in PR dotnet#19315. Fixes dotnet#17107 Co-authored-by: edgarfgp <31915729+edgarfgp@users.noreply.github.com> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Switch TryFindAttributeUsageAttribute to use tryBindTyconRefAttributeCore with ValueSome WellKnownILAttributes.AttributeUsageAttribute, enabling O(1) early exit on IL types that lack [AttributeUsage]. This avoids a full linear attribute scan at each level of the inheritance chain walk. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Description
The F# compiler was not walking the inheritance chain for IL-imported (C#) attribute types when checking AllowMultiple. The
supersOfTyconReffunction only usedtcaug_super, which is not populated for IL types.This fix parameterizes
TryFindAttributeUsageAttributewith a getSuper resolver function. The caller in PostInferenceChecks now passes a resolver using GetSuperTypeOfType, which correctly handles both F# and IL-imported types via ILTypeDef.Extends.Fixes #17107
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