Incorrect CA2021 Warning

[sra-michaelgold]

Description

Using 9.0.100-rc.2.24474.11 SDK

I'm getting incorrect CA2021 warning on valid code. See repro steps below.

Reproduction Steps

IEnumerable<BaseClass<int>> list = [new Implementation()];

var first = list.OfType<Implementation>().First();
Console.WriteLine(first.GetHashCode());


public abstract class BaseClass<T>
{
}

public sealed class Implementation : BaseClass<int>
{
}

Expected behavior

No warning

Actual behavior

Program.cs(3, 13): [CA2021] This call will always result in an empty sequence because type 'BaseClass' is incompatible with type 'Implementation' (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca2021)

Regression?

No response

Known Workarounds

Add NoWarn for CA2021 to csproj, but this is not optimal in case the issue actually exists.

Configuration

No response

Other information

9.0.100-rc.2.24474.11 SDK
Running in Rider 2024.2.7
Windows 10 x64

[vcsjones]

This looks like a duplicate of dotnet/roslyn-analyzers#7357.

I am going to close this as an existing issue has been identified in the appropriate repo, but feel free to re-open if you believe this was closed mistakenly.

[sra-michaelgold]

Thanks @vcsjones ! I agree it's a dupe. Apologies for not seeing the existing issue.