I finally had time to make a Xcode project to show the problem to Apple. The problem shows easily after loading some dylibs and has nothing to do with Xojo.
FB11721327 for anyone at Apple.
Screenshots like this:
you see crashes after 385, 442 and 506 dylibs.
I uploaded the sample project and the dylibs to Apple for testing.
And no plugin code is executed to make this fail.