[github-actions]

Backport of #135438 to release/11.0.

/cc @pavelsavara

Customer Impact

• Customer reported
• Found internally

Blazor WebAssembly AOT publishing deterministically crashes
mono-aot-cross with a native stack overflow when a value type contains a
generic value-type field instantiated over the containing type. The customer
reproduction is tracked by #132071 and reproduces on .NET 10 and .NET 11.

Regression

• Yes
• No

This is an existing Mono AOT compiler limitation rather than a regression.

Testing

The corrected backport removes the invalid mutually recursive generic test
types from #135029 that caused #135348. It retains only the valid
self-recursive shape and makes the helper types private.

• .\build.cmd -bl -os browser -subset mono+libs -c Release /p:RuntimeFlavor=Mono
  • Passed with 0 warnings and 0 errors.
• Mono browser AOT on Chrome,
  System.Tests.ValueTypeTests
  • AOT-compiled 80 assemblies.
  • 23/23 tests passed.
  • XHarness exit code 0.
• Original source-only Blazor reproduction from Blazor WASM AOT Compilation Failure #132071, using the
  release/11.0 mono-aot-cross
  • App assembly compiled successfully.
  • Dedup aot-instances.dll compiled successfully (14,712/14,747 methods).
• The corrected test shape was also verified on main before [mono][aot] Fix recursive struct wrapper normalization #135438:
  • The compiler without the fix exits with 0xC00000FD.
  • The compiler with the fix successfully compiles the same test assembly.

Risk

Low. The native change is limited to recursive gsharedvt wrapper-signature
normalization. It uses the existing non-shared fallback when a value type is
encountered again or the bounded recursion depth is reached. Acyclic value
types retain their prior normalization behavior. The corrected test avoids the
invalid cross-runtime metadata that caused the original CI regression.

IMPORTANT: If this backport is for a servicing release, please verify that:

• For .NET 8 and .NET 9: The PR target branch is release/X.0-staging, not release/X.0.
• For .NET 10+: The PR target branch is release/X.0 (no -staging suffix).

Package authoring no longer needed in .NET 9

IMPORTANT: Starting with .NET 9, you no longer need to edit a NuGet package's csproj to enable building and bump the version.
Keep in mind that we still need package authoring in .NET 8 and older versions.

Note

This PR description was updated with GitHub Copilot.

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[jkotas]

The tests introduced by this PR are failing - #135348 . The fix for these failures should be included in this PR.

[ViveliDuCh]

Hi,

the code complete date for GA is Monday 19th October. Make sure to merge this PR on that date at the latest, or it won't make it into that release.

As a reminder, if this is a product change, you also need Tactics approval before merging this PR (test-only or infra-only changes don't require Tactics approval).

Happy to help with the merge if needed!

[pavelsavara]

The tests introduced by this PR are failing - #135348 . The fix for these failures should be included in this PR.

Done