package pkg;

import java.io.Serializable;
import java.util.Comparator;

public interface TestUnionType {
   static Comparator comparingInt() {
      return (Comparator & Serializable)((c1, c2) -> {// 8
         return 1;
      }));
   }
}

class 'pkg/TestUnionType' {
   method 'lambda$comparingInt$ff46620a$1 (Ljava/lang/Object;Ljava/lang/Object;)I' {
      0      8
      1      8
   }

   method 'comparingInt ()Ljava/util/Comparator;' {
      5      7
      8      7
      b      7
   }
}

Lines mapping:
8 <-> 8