When building wildfly-core-eap 10.1.x and 11.0.x the following warning is shown:
[WARNING] Some problems were encountered while building the effective model for org.wildfly.core:wildfly-elytron-integration:jar:11.0.1.Final-redhat-SNAPSHOT
[WARNING] 'dependencies.dependency.(groupId:artifactId:type:classifier)' must be unique: org.wildfly.core:wildfly-controller-client:jar -> duplicate declaration of version (?) @ line 150, column 21
[WARNING] It is highly recommended to fix these problems because they threaten the stability of your build.
[WARNING] For this reason, future Maven versions might no longer support building such malformed projects.
The issue is the org.wildfly.core:wildfly-controller-client is added as a dependency in two scopes, for test and no explicit scope.
Removing the dependency declaration on the test scope fix the issue.
It seems it has been there since long time ago without any side effect but, it should be removed according to the warning