UnsupportedFeatureError: Unresolved element found at runtime

[dsyer]

If you build a native image with --report-unsupported-elements-at-runtime from code that does this:

		try {
			return NonExistentClass.class.isAssignableFrom(myClass);
		}
		catch (Throwable ex) {
			return false;
		}

it fails at runtime with UnsupportedFeatureError: Unresolved element found (a bit like #511 but different I think). You can work around it by doing a check for Class.forName("com.acme.NonExistentClass") before trying isAssignableFrom() it. Seems wrong, because a normal JVM behaves differently.

[dsyer]

Ping on this. I found another instance of this in Spring Boot (in addition to the two above). If Graal could just throw NoClassDefFoundError like a normal VM it would make these code paths work as expected. Is there any reason not to do that?

[n0mer]

@cstancu are you maybe ready to share updates on this ticket?

[cstancu]

We have a new, experimental flag: --allow-incomplete-classpath which should take care of cases like this. You can try it by building GraalVM from source. This will be available in the next release, rc10.

[cstancu]

This is now supported via the --allow-incomplete-classpath flag.