Snippet to reproduce:

package test;
public class SomeClass {

	public static Class<?> cl = SomeClass.class;
	private String unusedField;
}

For unusedField, nothing is reported. After commenting out public static Class<?> cl = SomeClass.class;, a bug is reported as expected.

Seems to be coming from: 9ae2687

In particular as soon as LDC Ltest/SomeClass;.class is seen, SomeClass is assumed to be accessed with reflection and the change above suppresses the unused field bug report.