Trim RefSafetyRulesAttribute when trimming aggressively

[MichalStrehovsky]

This is another attribute that Roslyn uses for its own purposes only.

Cc @dotnet/illink-contrib (btw what's the difference between this and @dotnet/illink?)

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Issue Details

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This is another attribute that Roslyn uses for its own purposes only.

Cc @dotnet/illink-contrib (btw what's the difference between this and @dotnet/illink?)

Author:	MichalStrehovsky
Assignees:	-
Labels:	linkable-framework
Milestone:	-

[eerhardt]

As the C# compiler adds more and more of these, is there a way to keep this list up-to-date, or at least a way to audit when new attributes are added by the C# compiler?

From @333fred - #85612 (comment) lists all the attributes emitted by the compiler.

Also note - a bunch of these attributes are now in CoreLib with #87857.

[MichalStrehovsky]

We can't strip everything the compiler injects because some of these are "public APIs" (we tell people how to interpret them, like the nullable attributes). Then there's those with unknown purpose like RefSafetyRulesAttribute or EmbeddedAttribute that only mean something to Roslyn.

Roslyn should ideally have a holistic look at this because in 10 years we'll have 20 attributes that cost us 20 kB (need to count IL size, metadata size, readytorun code size) to encode 20 bytes of information in each assembly - #85612 (comment). If we could have a RoslynBreadcrumbsAttribute that takes a byte[] that Roslyn can decode, it might be more space efficient than a new type for every tiny bit of information.