This can be reproduced by running WithClauseTest#testWithClauseAsSubqueryWithKeyAndOtherJoinReference on an affected DB vendor.

The problematic query: https://github.com/hibernate/hibernate-orm/blob/5.1.8/hibernate-core/src/test/java/org/hibernate/test/hql/WithClauseTest.java#L250

concat('son', friend.intValue) translates into SQL 'son'+human2_.intValue, but on MS SQL this fails with

Conversion failed when converting the varchar value 'son' to data type int.

and on Sybase with

Implicit conversion from datatype 'VARCHAR' to 'INT' is not allowed.  Use the CONVERT function to run this query.