CoreRT support

[tjm00]

Does coreRT support fall within this project's goal of portability? Running a console program compiled with coreRT that uses this library results in an unhandled System.TypeInitializationException. It looks like it is related to reflection, somewhere around Org.BouncyCastle.Utilities.Enums.GetArbitraryValue(Type), but the error was a bit more obscure than usual so I haven't dug to far into it.

[clairernovotny]

It should work there, though errors are likely on the CoreRT side as this is a netstandard2.0 library. If you can provide a repro, I can raise it with the right team.

[tjm00]

It looks like this one-liner is sufficient to reproduce it: X9ECParameters bcCurve = NistNamedCurves.GetByName("P-521");.

[clairernovotny]

Is there a minimal project you could zip up and attach here (or a repo you can point to)?

[tjm00]

This does it for me.

[clairernovotny]

Thanks, looking into where the issue goes.

[MichalStrehovsky]

The best way to report CoreRT issues is to report them in the CoreRT repo, along with the stack trace and full exception information (we might not even have to spend time reproing this because some stacks are pretty obvious).

The stack trace for this one is:

Unhandled Exception: System.TypeInitializationException: A type initializer threw an exception. To determine which type, inspect the InnerException's StackTrace property. ---> System.TypeInitializationException: A type initializer threw an exception. To determine which type, inspect the InnerException's StackTrace property. ---> System.Reflection.MissingMetadataException: 'Org.BouncyCastle.Security.DigestUtilities.DigestAlgorithm[]' is missing metadata. For more information, please visit http://go.microsoft.com/fwlink/?LinkID=392859
   at CorertRepro!<BaseAddress>+0x37596
   at CorertRepro!<BaseAddress>+0x9053a
   at CorertRepro!<BaseAddress>+0x155979
   at CorertRepro!<BaseAddress>+0x37311
   at CorertRepro!<BaseAddress>+0x53925
   at System.Enum.GetValues(Type) + 0xb4
   at Org.BouncyCastle.Utilities.Enums.GetArbitraryValue(Type) + 0x9
   at CorertRepro!<BaseAddress>+0x819dd
   at CorertRepro!<BaseAddress>+0x13c890

This is an Enum.GetValues call trying to get values for a specific enum, but the AOT compiler didn't know we would need to generate code for the array of the enum. There are multiple ways to fix this:

• Include a static reference to Org.BouncyCastle.Security.DigestUtilities.DigestAlgorithm[] somewhere (new up the array in code). That way we'll be able to find the code at runtime.
• If your code doesn't rely on the semantic of Enum.GetValues returning a precise instance of the enum array, you can specify <AppContextSwitchOverrides Include="Switch.System.Enum.RelaxedGetValues" /> in one of the ItemGroups of your project. This will cause Enum.GetValues to return an array of the underlying type (so int[]), which is more likely to be available. (You'll see casting problems if the code takes dependency on this undocumented behavior.)
• Use attached default.rd.zip and add it to your project as <RdXmlFile Include="default.rd.xml" /> in one of your ItemGroups

[clairernovotny]

The CoreRT repo is here: https://github.com/dotnet/corert/issues

Thanks for chiming in @MichalStrehovsky!

[clairernovotny]

Closed as external

[tjm00]

Thank you both.