.NET: Suppress IL2026/IL3050 trimming diagnostics in hosting projects

[rogerbarreto]

Motivation and Context

Add NoWarn for IL2026 and IL3050 to the OpenAI and AGUI hosting projects only. These projects use ASP.NET Core endpoint routing APIs that trigger RequiresUnreferencedCode/RequiresDynamicCode attribute propagation, causing dotnet format to auto-add unwanted attributes. The suppression is scoped to these projects so the diagnostics remain active elsewhere.

[Copilot]

Pull request overview

This PR suppresses the IL2026 (RequiresUnreferencedCode) and IL3050 (RequiresDynamicCode) compiler diagnostics in the two hosting projects that use ASP.NET Core minimal API endpoint routing (MapPost, MapGet, etc.) with the Request Delegate Generator enabled. These diagnostics are otherwise propagated by dotnet format, causing unwanted attribute additions. The suppressions are narrowly scoped to only the affected projects.

Changes:

• Add IL2026 and IL3050 to NoWarn in the OpenAI hosting project (alongside the existing MEAI001 suppression).
• Add a new NoWarn line with IL2026 and IL3050 to the AGUI ASP.NET Core hosting project.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
dotnet/src/Microsoft.Agents.AI.Hosting.OpenAI/Microsoft.Agents.AI.Hosting.OpenAI.csproj	Appends IL2026 and IL3050 to the existing NoWarn list
dotnet/src/Microsoft.Agents.AI.Hosting.AGUI.AspNetCore/Microsoft.Agents.AI.Hosting.AGUI.AspNetCore.csproj	Adds a new NoWarn property suppressing IL2026 and IL3050

[stephentoub]

Wouldn't it be better to fix these and remain NativeAOT-friendly than to suppress the warnings?

[rogerbarreto]

Wouldn't it be better to fix these and remain NativeAOT-friendly than to suppress the warnings?

@stephentoub, as stated by @DeagleGross awhile ago.

"there is a bug in dotnet format where it does not respect IL2026 and IL3050 even when proper configuration was supplied to the csproj. Those warnings rise on the attempt to add endpoint handlers to the IEndpointRouteBuilder like app.MapGet("/", () => "hello world") in AOT scenarios where endpoint handler code has to be generated."

• dotnet format does not respect interceptors for Request Delegate Generator dotnet/sdk#51136

[stephentoub]

Wouldn't it be better to fix these and remain NativeAOT-friendly than to suppress the warnings?

@stephentoub, as stated by @DeagleGross awhile ago.

"there is a bug in dotnet format where it does not respect IL2026 and IL3050 even when proper configuration was supplied to the csproj. Those warnings rise on the attempt to add endpoint handlers to the IEndpointRouteBuilder like app.MapGet("/", () => "hello world") in AOT scenarios where endpoint handler code has to be generated."

• dotnet format does not respect interceptors for Request Delegate Generator dotnet/sdk#51136

Fixes for that were already merged. Does the repo just need a newer SDK?

Suppressing these for the whole project like this means we won't know if there are any other issues that creep in.

[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.

[rogerbarreto]

Suppressing these for the whole project like this means we won't know if there are any other issues that creep in.

@stephentoub, agree, updated to the specific methods, with the comment on the tracking issue.