Bug: Conditional Operator stores ref result in a non-ref-temporary (Only when SpillSequenceSpiller is used - e.g. for async/await)

[bernd5]

Bug: Conditional Operator stores ref result in a non-ref-temporary (Only when SpillSequenceSpiller is used - e.g. for async/await)

[bernd5]

A simpler version (makes use of spilling with general is pattern):

string str = "a2";
int x = 1;
int y = 2;

ref int r =
      ref str is "Hallo" ? ref x
    : ref str is { Length: >= 2 and <= 10 or 22 } ? ref y
    : ref System.Runtime.CompilerServices.Unsafe.NullRef<int>();

r++;
r++;
r++;
int xxx = r;
System.Console.WriteLine(xxx); //5
System.Console.WriteLine(x); //1
System.Console.WriteLine(y); //expected 5 - but we get 2

[bernd5]

And a version with ref readonly:

using System;


string str = "a2";
int x = 1;
int y = 2;

ref readonly var xx = ref x; 

ref readonly int r =
      ref Eval(str, 1) is "Hallo" ? ref xx
    : ref Eval(str, 2) is { Length: >= 2 and <= 10 or 22 } ? ref y
    : ref System.Runtime.CompilerServices.Unsafe.NullRef<int>();

ref var rx = ref System.Runtime.CompilerServices.Unsafe.AsRef(in r);

rx++;
rx++;
rx++;
int xxx = r;
System.Console.WriteLine(xxx);
System.Console.WriteLine(x);
System.Console.WriteLine(y);


static T Eval<T>(T s, int i)
{
    System.Console.WriteLine($"{s} {i}");
    return s;
}