Ref local variable is inlined incorrectly, changing the exception behavior

[dgrunwald]

Input code

using System;
class Program {
    static int GetInt()
    {
        Console.WriteLine("got int");
        return 42;
    }

    int intField;

    static void FieldAccessOrderOfEvaluation(Program c)
    {
        Console.WriteLine("NRE before GetInt:");
        try {
            ref int i = ref c.intField;
            i = GetInt();
        } catch (Exception ex) {
            Console.WriteLine(ex.Message);
        }
    }
}

Erroneous output

    private static void FieldAccessOrderOfEvaluation(Program c)
    {
        Console.WriteLine("NRE before GetInt:");
        try
        {
            c.intField = GetInt();
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.Message);
        }
    }

This output is wrong because when called with c == null, the GetInt side-effect will happen before the NullReferenceException is throws, whereas in the original code the exception was thrown before GetInt was called.

Expected output

Same as original input.

Details

• Product in use: e.g. ILSpy
• Version in use: da905ac