Re-enable Release AOT by excluding only OpenCvSharp.dll

[shimat]

Summary

• Full AOT-compiling the app in Release currently crashes mono-aot-cross while precompiling OpenCvSharp.dll (native GC assertion, sgen-alloc.c:409) — see shimat/opencvsharp_blazor_sample#8. A minimal repro isolated the trigger to OpenCvSharp.dll's own P/Invoke surface (~3100 LibraryImport declarations), not native lib size or NativeFileReference in general — a tiny test app referencing the same large native .a but only 3 fake LibraryImport methods AOT-compiled fine.
• Since the actual OpenCV computation happens in native C++ regardless of whether this thin C# marshalling layer is AOT-compiled or interpreted, this PR shadows the SDK's internal _WasmAotCompileApp target to exclude just OpenCvSharp.dll from the AOT set (it still ships as plain IL, executed by the interpreter at runtime) while the rest of the app gets full AOT.
• RunAOTCompilation is back to true (default) for Release — was false since Add GitHub Pages deploy workflow #7, as a stopgap while full AOT was completely broken.

Test plan

• dotnet publish -c Release -p:RunAOTCompilation=true succeeds: "AOT'ing 38 assemblies" completes with no crash — https://github.com/shimat/opencvsharp_blazor_sample/actions/runs/29156433420
• Confirmed OpenCvSharp.<hash>.wasm is still present in the published _framework output (not silently dropped)
• Full deploy-pages.yml pipeline (publish + Pages artifact) succeeds end-to-end with AOT back on — https://github.com/shimat/opencvsharp_blazor_sample/actions/runs/29157608898 (the deploy job there only failed due to the github-pages environment's main-only protection rule, expected on a feature branch)

Caveat

This shadows an internal, undocumented SDK target (_WasmAotCompileApp) by name — its shape may change in a future wasm-tools workload update. If a future SDK bump breaks this (build error, or the exclusion silently stops working), fall back to <RunAOTCompilation>False</RunAOTCompilation> for Release as before.

🤖 Generated with Claude Code

Summary by CodeRabbit

• Performance
  • Enabled Ahead-of-Time (AOT) compilation for Release builds to improve application startup and runtime performance.
  • Added compatibility handling so OpenCvSharp continues to work correctly when AOT compilation is enabled.

[coderabbitai]

📝 Walkthrough

Walkthrough

Release builds now enable WebAssembly AOT compilation. MSBuild temporarily removes OpenCvSharp from the AOT assembly list during compilation, then restores it afterward.

Changes

AOT handling

Layer / File(s)	Summary
Configure AOT assembly handling BlazorApp/BlazorApp.csproj	Release enables RunAOTCompilation; new targets exclude OpenCvSharp before wasm AOT compilation and re-add it afterward.

Estimated code review effort: 2 (Simple) | ~10 minutes

Possibly related issues

• Issue #8 — Re-enables AOT while excluding OpenCvSharp to avoid its AOT compilation failure.

Poem

I’m a bunny with builds that now hop,
AOT runs while OpenCvSharp stops.
Removed for the flight,
Restored after the byte,
Clean wasm paths make my ears flop.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately and concisely summarizes the main change: re-enabling Release AOT while excluding only OpenCvSharp.dll.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch experiment/partial-aot-exclude-opencvsharp

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[coderabbitai]

🧹 Nitpick comments (1)

BlazorApp/BlazorApp.csproj (1)

81-87: 🩺 Stability & Availability | 🔵 Trivial | ⚡ Quick win

Add a warning when OpenCvSharp is not found in the AOT assembly list.

If a future SDK update renames _WasmAssembliesInternal or changes its item metadata, _OpenCvSharpAssemblyToSkipAOT would be empty. The Message on line 86 would print "Excluding from AOT: " (nothing after the colon), which looks like success but means the workaround is silently inactive — OpenCvSharp would then be AOT'd and crash mono-aot-cross. Adding a conditional warning when the captured item is empty makes this failure mode loud instead of silent.

⚠️ Proposed fix: warn when the item is empty

   <Target Name="ExcludeOpenCvSharpFromAOT" BeforeTargets="_WasmAotCompileApp" Condition="'$(_WasmShouldAOT)' == 'true'">
     <ItemGroup>
       <_OpenCvSharpAssemblyToSkipAOT Include="@(_WasmAssembliesInternal)" Condition="'%(FileName)' == 'OpenCvSharp'" />
       <_WasmAssembliesInternal Remove="@(_OpenCvSharpAssemblyToSkipAOT)" />
     </ItemGroup>
-    <Message Importance="High" Text="Excluding from AOT: @(_OpenCvSharpAssemblyToSkipAOT)" />
+    <Message Importance="High" Text="Excluding from AOT: @(_OpenCvSharpAssemblyToSkipAOT)" Condition="'@(_OpenCvSharpAssemblyToSkipAOT)' != ''" />
+    <Warning Text="OpenCvSharp was not found in _WasmAssembliesInternal — the AOT exclusion workaround may be inactive. Check if the SDK changed the internal item name/metadata." Condition="'@(_OpenCvSharpAssemblyToSkipAOT)' == ''" />
   </Target>

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@BlazorApp/BlazorApp.csproj` around lines 81 - 87, Update the
ExcludeOpenCvSharpFromAOT target to emit a warning when
_OpenCvSharpAssemblyToSkipAOT is empty, while preserving the existing
high-importance exclusion message and removal behavior when OpenCvSharp is
found. Use a condition on the warning so the inactive workaround is reported
clearly without adding an unconditional warning.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@BlazorApp/BlazorApp.csproj`:
- Around line 81-87: Update the ExcludeOpenCvSharpFromAOT target to emit a
warning when _OpenCvSharpAssemblyToSkipAOT is empty, while preserving the
existing high-importance exclusion message and removal behavior when OpenCvSharp
is found. Use a condition on the warning so the inactive workaround is reported
clearly without adding an unconditional warning.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 6fc83de0-4571-407a-aa98-5849055eae72

📥 Commits

Reviewing files that changed from the base of the PR and between 028beb1 and 8efd32c.

📒 Files selected for processing (1)

• BlazorApp/BlazorApp.csproj