AOT compiler for .NET/iOS not built with MONOTOUCH defined

[rolfbjarne]

Description

The symptom is that an AOT-compiled iOS app can crash at runtime on device with:

error: Ran out of trampolines of type 0 in '/private/var/containers/Bundle/Application/D21C45AD-25AB-4FD9-A08F-706A43A7974D/link all.app/System.Private.CoreLib.dll' (limit 4096). See http://docs.xamarin.com/ios/troubleshooting for instructions on how to fix this condition.

I diagnosed a bit, and the reason is that this line is never executed:

runtime/src/mono/mono/mini/aot-compiler.c

Lines 13778 to 13780 in d85f060

	#ifdef MONOTOUCH
	acfg->aot_opts.use_trampolines_page = TRUE;
	#endif

which presumably happens because MONOTOUCH isn't defined.

I decompiled the AOT compiler shipped with .NET, and the one we currently use for Xamarin.iOS, and only the latter contains the line above.

.Mono for Xamarin.iOS: https://gist.github.com/rolfbjarne/8607804c44f873ebf6ef711e50f30134#file-foo-diff-L217-L223
.NET: https://gist.github.com/rolfbjarne/37cebf4f43296d9f51474944dd424650#file-foo-diff-L219-L224

This is the missing line: https://gist.github.com/rolfbjarne/8607804c44f873ebf6ef711e50f30134#file-foo-diff-L222

CC @akoeplinger

[Dotnet-GitSync-Bot]

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[akoeplinger]

/cc @vargaz

[imhameed]

This should be fixed; does this particular crash still happen? (I haven't personally gotten to the point where I've run an AOT-compiled app on-device, so it might take me a little while to create and test a repro.)

[rolfbjarne]

This should be fixed; does this particular crash still happen?

I'll check once there are .NET packages with the fix.

[rolfbjarne]

This is fixed.