Useless enforcement of CG.SuppressFinalize

[ericbl]

The rules CA1816 and CA1063 are annoying me for a small detail for over 10 years: why is the CA1816 and CA1063 still forcing a call to the CG.SuppressFinalize method when the class do NOT have any finalizer?
As stated in the IDispose snippet in VS, by Stephen Cleary in his blog here:
https://blog.stephencleary.com/2009/08/second-rule-of-implementing-idisposable.html
a class implementing IDisposable with only managed objects should NOT have any finalizer, and do NOT need a call to CG.SuppressFinalize

Adding CG.SuppressFinalize will not harm since
https://docs.microsoft.com/en-us/dotnet/api/system.gc.suppressfinalize?redirectedfrom=MSDN&view=net-5.0#System_GC_SuppressFinalize_System_Object_

If obj does not have a finalizer or the GC has already signaled the finalizer thread to run the finalizer, the call to the SuppressFinalize method has no effect.

but this is just useless: every .NET developer dealing mostly with managed code is adding a line of code for nothing in his code.

IMHO, it would be much better to detect if the class has a finalizer, and if no finalizer, do not ask for SuppressFinalize !
Even better would be to detect for unmanaged ressources and only then ask for a finalizer and possibly SuppressFinalize as in the 3rd rule of implementing IDisposable:
https://blog.stephencleary.com/2009/08/third-rule-of-implementing-idisposable.html

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• ID: 3fd3e94e-7b6f-21ad-4c90-460e60482ab5
• Version Independent ID: 15958b42-33bb-4925-2d78-eb72113ba3eb
• Content: CA1816: Call GC.SuppressFinalize correctly (code analysis) - .NET
• Content Source: docs/fundamentals/code-analysis/quality-rules/ca1816.md
• Product: dotnet-fundamentals
• GitHub Login: @gewarren
• Microsoft Alias: gewarren

[Evangelink]

I am wondering if there are cases where it brings something.

@mavasani if this ticket moves forward the analyzer should be updated.

[gewarren]

This issue was moved to dotnet/roslyn-analyzers#4482