Type inference bug?

[sunnycase]

Version Used: Visual Studio 2017

Steps to Reproduce:

    public static class NullExt
    {
        public static T? Some<T>(this T? value, Action<T> func) where T : struct
        {
            if (value != null)
                func(value.Value);
            return value;
        }

        public static T Some<T>(this T value, Action<T> func) where T : class
        {
            if (value != null)
                func(value);
            return value;
        }
    }

    class Program
    {
        public static void Main()
        {
            string s = "s";
            s.Some(_ => Console.Write("some"));

            int? i = 1;
            i.Some(_ => Console.Write("some"));
        }
    }

Expected Behavior:
This code snippet compiles.

Actual Behavior:
This code snippet doesn't compiles.
error CS0121: The call is ambiguous between the following methods or properties: “NullExt.Some(T?, Action)” and “NullExt.Some(T, Action)”

Change

            i.Some(_ => Console.Write("some"));

to

            i.Some<int>(_ => Console.Write("some"));

it compiles, So i think it's a type inference bug. What do you think of this?

[shikimoon]

It's very helpful to me

[gafter]

This is probably not a bug, but a case where dotnet/csharplang#98 would help.