The T in Lazy<T> is marked DynamicallyAccessedMemberTypes.PublicParameterlessConstructor

[eiriktsarpalis]

This is presumably there to support the default constructor which instantiates default instances via the Activator, but it creates false positives in AOT compatible projects consuming Lazy<T> without using reflection. For example, the following method issues a warning:

static Lazy<T> Create<T>(Func<T> factory) => new(factory);

forcing authors to either suppress the warning or virally add DynamicallyAccessedMemberTypes annotations to every generic method consuming Create. I'm not aware of any workarounds other than marking the default constructor as RequiresUnreferencedCode but presumably this would create regressions in trimmed apps using the default constructor. I'm wondering if there's a way we could specify DynamicallyAccessMembers on a type parameter in a way that is scoped to a particular constructor overload.

cc @vitek-karas @eerhardt for thoughts.

[stephentoub]

Very similar to the discussion here:
#89002 (comment)

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[Sergio0694]

We hit this in a few places in the Store as well. Glad to see there seems to be an increase in interest in this 😄
@teo-tsirpanis' suggestion in #89002 (comment) seems interesting, assuming it's doable...