Parameter name stripping breaks debugger

[MichalStrehovsky]

We've been weary of doing optimizations that might affect debuggability, such as stripping unused properties. On the other hand, we strip parameter names. The following program:

class Program
{
    static void Main()
    {
        Test(null, null, null);
    }

    static void Test(string a, string b, string c)
    {
        string d = a;
        KeepLocal(ref d);
    }

    static void KeepLocal<T>(ref T t) { }
}

Looks like this under debugger:

We should probably decide whether we're fine breaking debugger and either stop doing this optimization unless DebuggerSupport is false, or open floodgates to more optimizations like this.

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[sbomer]

Thanks for pointing this out! Putting it under DebuggerSupport would make sense to me.