The commons-logging classes in spring-core (see #19081) seem to contain 2 copies of the source code (in the same file for each class). I think that makes them unreadable by Eclipse because I can't read the code in the IDE.
Affects: 5.0 RC1
#19081 Revisit Commons Logging vs java.util.logging vs SLF4J vs Log4j 2
Stéphane asked me to take a look at this. It's caused by a bug in Kotlin's Gradle plugin that causes src/main/java to be listed twice in sourceSets.main.allSource. You can work around the problem by setting duplicatesStrategy = DuplicatesStrategy.EXCLUDE on the sourcesJar task.