Threading is somehow included in my Flash Build, how to I track down what's using it?

Questions & Answers
1

I’m making a flash build of a tiny game. When I started porting it, there were a ton of issues being thrown by the build step FlashDotNetAPIValidationRule (things like System.TextBuilder.AppendLine is not supported). These were easy enough to port, but now I’m down to my last error:

 Usage of a type or method not supported by Unity Flash.
* Details:   Invokes an unsupported method System.Int32 System.Threading.Interlocked::CompareExchange(System.Int32&,System.Int32,System.Int32) on type System.Threading.Interlocked
* Source:   debugging symbols unavailable, IL offset 0x0009 at line : 0

I’ve searched around my project for anything obvious that would be using threads and then I just started commenting out systems that could even conceivably touch threads, but I haven’t figured out what’s using threads. Does anyone have any advice for tracing code dependencies so that I can debug this sort of problem?

2

If all your assemblies are compiled by Unity, then setting “development build” checkbox in the build menu will allow you to track these down.

3

This issue is caused with yields in for loops:

public IEnumerable<Moo> Moos
{
   get
   {
      foreach (Moo moo in moos)
          yield return moo;  // ERROR
   }
}

To solve it, do not return the enumerated object.

public IEnumerable<Moo> Moos
{
   get
   {
#if UNITY_FLASH
      List<Moo> res = new List<Moo>(); 
      foreach (Moo moo in moos)
          res.Add(moo); 
      return res;  // somewhat defeats the purpose, but wth
#else
      foreach (Moo moo in moos)
          yield return moo;  // ERROR
#endif

   }
}

Enjoy,
frevd