Darius St. ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=712020%... ) *commented* on HHH-16903 ( https://hibernate.atlassian.net/browse/HHH-16903?atlOrigin=eyJpIjoiMDU5Yz... ) Re: java.lang.IllegalStateException: Illegal pop() with non-matching JdbcValuesSourceProcessingState ( https://hibernate.atlassian.net/browse/HHH-16903?atlOrigin=eyJpIjoiMDU5Yz... ) Hi, I am in the process of migrating an application from Hibernate 5.7 to Hibernate 6.2 and I think I'm also affected by this issue. I'm getting the same exception when loading an entity that contain lazy-loaded fields. As soon as I declare the fields non-lazy the exception disappear. I loading the entity in a single thread so no multithreading is involved. The mapping is defined in HBM XML format. When I change the attribute "default-lazy" in the "hibernate-mapping" XML element from "true" to "false" the exception no longer is thrown. The Stacktrace I'm getting with Hibernate 6.2.6 is Caused by: java.lang.IllegalStateException: Illegal pop() with non-matching JdbcValuesSourceProcessingState at org.hibernate.sql.results.spi.LoadContexts.deregister(LoadContexts.java:46) at org.hibernate.sql.results.spi.ListResultsConsumer.consume(ListResultsConsumer.java:209) at org.hibernate.sql.results.spi.ListResultsConsumer.consume(ListResultsConsumer.java:33) at org.hibernate.sql.exec.internal.JdbcSelectExecutorStandardImpl.doExecuteQuery(JdbcSelectExecutorStandardImpl.java:362) at org.hibernate.sql.exec.internal.JdbcSelectExecutorStandardImpl.executeQuery(JdbcSelectExecutorStandardImpl.java:168) at org.hibernate.sql.exec.internal.JdbcSelectExecutorStandardImpl.list(JdbcSelectExecutorStandardImpl.java:93) at org.hibernate.sql.exec.spi.JdbcSelectExecutor.list(JdbcSelectExecutor.java:31) at org.hibernate.loader.ast.internal.SingleIdLoadPlan.load(SingleIdLoadPlan.java:145) at org.hibernate.loader.ast.internal.SingleIdLoadPlan.load(SingleIdLoadPlan.java:117) at org.hibernate.loader.ast.internal.SingleIdEntityLoaderStandardImpl.load(SingleIdEntityLoaderStandardImpl.java:72) at org.hibernate.persister.entity.AbstractEntityPersister.doLoad(AbstractEntityPersister.java:3381) at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:3371) at org.hibernate.event.internal.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:602) at org.hibernate.event.internal.DefaultLoadEventListener.loadFromCacheOrDatasource(DefaultLoadEventListener.java:588) at org.hibernate.event.internal.DefaultLoadEventListener.load(DefaultLoadEventListener.java:557) at org.hibernate.event.internal.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:550) at org.hibernate.event.internal.DefaultLoadEventListener.load(DefaultLoadEventListener.java:202) at org.hibernate.event.internal.DefaultLoadEventListener.doOnLoad(DefaultLoadEventListener.java:101) at org.hibernate.event.internal.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:78) at org.hibernate.event.service.internal.EventListenerGroupImpl.fireEventOnEachListener(EventListenerGroupImpl.java:138) at org.hibernate.internal.SessionImpl.fireLoadNoChecks(SessionImpl.java:1231) at org.hibernate.internal.SessionImpl.immediateLoad(SessionImpl.java:1043) at org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:173) at org.hibernate.proxy.AbstractLazyInitializer.getImplementation(AbstractLazyInitializer.java:310) ( https://hibernate.atlassian.net/browse/HHH-16903#add-comment?atlOrigin=ey... ) Add Comment ( https://hibernate.atlassian.net/browse/HHH-16903#add-comment?atlOrigin=ey... ) Get Jira notifications on your phone! Download the Jira Cloud app for Android ( https://play.google.com/store/apps/details?id=com.atlassian.android.jira.... ) or iOS ( https://itunes.apple.com/app/apple-store/id1006972087?pt=696495&ct=Em... ) This message was sent by Atlassian Jira (v1001.0.0-SNAPSHOT#100232- sha1:33a7c72 )