Don't trim ShouldSerializeXXX and ResetXXX members that may be called with reflection

[steveharter]

Fixes #102244

This change makes sure these members exist in the inbox version of the System.Data.Common assembly.

The TypeDescriptor reflection-based model, the XML serializer, and the Json.NET serializer use these naming conventions to call the members with reflection.

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[MichalStrehovsky]

This doesn't look like the right fix. #102244 (comment) and the subsequent discussion discuss why.

I think this should use ILLink.LibraryBuild file like the original issue was suggesting so that these get preserved when we build the repo. After repo build it can be trimmed like anything else. ILLink.LibraryBuild is designed for these cases.

These DynamicDependency will keep things unconditionally in trimmed apps even if nobody uses TypeDescriptor/Json.NET/etc. It's a global fix for a local problem. It will regress the size for everyone, including the well behaved apps that don't use trim unsafe code this tries to fix. Everything that could need this should already be marked as trim unsafe. We don't need trim unsafe code to work in trimmed apps, it is okay and expected that trim unsafe code will be broken after trimming. It is the responsibility of whoever is turning on trimming on trim unsafe code to author XML descriptors if they wish to take the hard path.

The TypeDescriptor reflection-based model and the XML and Json.NET serializers use these conventions.

These are also trim unsafe and not expected to work after trimming. The issue this PR tries to address is a drop in the bucket, there are more fundamental trimming problems with these serializers.

[steveharter]

This doesn't look like the right fix. #102244 (comment) and the subsequent discussion discuss why.This doesn't look like the right fix. #102244 (comment) and the subsequent discussion discuss why.

I assume the change requested here is to move the DynamicDependency from source to XML like this:

    <type fullname="System.Data.DataSet">
      <method signature="System.Void .ctor()">
        <attribute fullname="System.Diagnostics.CodeAnalysis.DynamicDependencyAttribute">
          <argument>ResetRelations</argument>
        </attribute>

however, when I do that it appears trimming already occurred, meaning in the example above I'll get this error when building:

C:\git\ComponentModel\src\libraries\System.Data.Common\src\System\Data\DataSet.cs(47,9): error IL2037: System.Data.DataSet.DataSet(): No members were resolved for 'ResetRelations' on type 'System.Data.DataSet'. [C:\git\ComponentModel\src\libraries\sfx.proj]

[jkotas]

I assume the change requested here is to move the DynamicDependency from source to XML like this:

Yes, it should be in ILLink.Descriptors.LibraryBuild.xml.

however, when I do that it appears trimming already occurred, meaning in the example above I'll get this error when building:

I am not sure where this error is coming from. Could you please apply the change so that we can see it?

[steveharter]

Yes, it should be in ILLink.Descriptors.LibraryBuild.xml.

I saw that right after I posted; I was using the wrong xml file. I added src\libraries\System.Data.Common\src\ILLink which is working.

[MichalStrehovsky]

I'm not reviewing whether this list is complete, but the approach looks good to me! Thanks!

[steveharter]

This should be considered for servicing once verified.

[SamMonoRT]

@roji @AndriySvyryd fyi --