Hi all, We are observing very infrequent assertion errors originating in getUpperBoundASTs, mostly during concurrent builds on our build machine, when it's under a heavy load. This has been happening from time to time with various Java versions; most recently with 1.8.0_131.
I don't see anything in Jira about it, but even a quick Google search yields some hits [1]. The stack trace starts with (I include the jackson stack frame which calls it): java.lang.AssertionError: null at sun.reflect.generics.reflectiveObjects.WildcardTypeImpl.getUpperBoundASTs(WildcardTypeImpl.java:86) ~[?:1.8.0_131] at sun.reflect.generics.reflectiveObjects.WildcardTypeImpl.getUpperBounds(WildcardTypeImpl.java:122) ~[?:1.8.0_131] at com.fasterxml.jackson.databind.type.TypeFactory._fromWildcard(TypeFactory.java:1424) ~[jackson-databind-2.8.2.jar:2.8.2] The problem cannot be easily reproduced, but I see a comment mentioned on the core-libs-dev a while ago [2] by Joel Borggrén-Franck, so perhaps his question is a valid one and worth investigating: > Btw, has anyone seen the assert for upper/lower bounds == null fail in the > wild? Dawid [1] https://www.google.com/search?q=getUpperBoundASTs+AssertionError&filter=0&biw=1279&bih=863 (note the "[JENKINS] Lucene-olr-master-Linux" hit). [2] http://markmail.org/message/4phfnh7dj3qdlo6b
