A vanilla spring boot project print warning with v3.1.0-RC1, and it works fine with v3.0.6.
$ gradle -v
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Gradle 8.1
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Build time: 2023-04-12 12:07:45 UTC
Revision: 40ba32cde9d6daf2b92c39376d2758909dd6b813
Kotlin: 1.8.10
Groovy: 3.0.15
Ant: Apache Ant(TM) version 1.10.11 compiled on July 10 2021
JVM: 17.0.5 (Eclipse Adoptium 17.0.5+8)
OS: Mac OS X 13.3.1 x86_64
$ gradle test
> Task :test
OpenJDK 64-Bit Server VM warning: Sharing is only supported for boot loader classes because bootstrap classpath has been appended
Here is sample project warning.zip
Comment From: wilkinsona
This is caused by Mockito. If you downgrade to 4.8.1 (the version used in 3.0.6) it does not occur.