While building Controller project, Maven prints several warnings, most originating from config subsystem.

Currently on Nitrogen (visible in merge job console log):

[INFO] Scanning for projects...
[WARNING]
[WARNING] Some problems were encountered while building the effective model for org.opendaylight.controller:md-sal-config:jar:1.6.0-SNAPSHOT
[WARNING] 'build.plugins.plugin.version' for org.codehaus.mojo:build-helper-maven-plugin is missing. @ line 27, column 17
[WARNING]
[WARNING] Some problems were encountered while building the effective model for org.opendaylight.controller.samples:clustering-it-config:jar:1.6.0-SNAPSHOT
[WARNING] 'build.plugins.plugin.version' for org.codehaus.mojo:build-helper-maven-plugin is missing. @ org.opendaylight.controller.samples:clustering-it-config:[unknown-version], /home/odl/build/controller/opendaylight/md-sal/samples/clustering-test-app/configuration/pom.xml, line 21, column 17
[WARNING]
[WARNING] Some problems were encountered while building the effective model for org.opendaylight.controller:sal-clustering-config:jar:1.6.0-SNAPSHOT
[WARNING] 'build.plugins.plugin.version' for org.codehaus.mojo:build-helper-maven-plugin is missing. @ line 27, column 15
[WARNING]
[WARNING] Some problems were encountered while building the effective model for org.opendaylight.controller:messagebus-config:jar:1.6.0-SNAPSHOT
[WARNING] 'build.plugins.plugin.version' for org.codehaus.mojo:build-helper-maven-plugin is missing. @ line 27, column 15
[WARNING]
[WARNING] Some problems were encountered while building the effective model for org.opendaylight.controller:threadpool-config-api:bundle:0.7.0-SNAPSHOT
[WARNING] 'build.plugins.plugin.version' for org.opendaylight.yangtools:yang-maven-plugin is missing. @ org.opendaylight.controller:threadpool-config-api:[unknown-version], /home/odl/build/controller/opendaylight/config/threadpool-config-api/pom.xml, line 35, column 15
[WARNING]
[WARNING] Some problems were encountered while building the effective model for org.opendaylight.controller:threadpool-config-impl:bundle:0.7.0-SNAPSHOT
[WARNING] 'build.plugins.plugin.version' for org.opendaylight.yangtools:yang-maven-plugin is missing. @ org.opendaylight.controller:threadpool-config-impl:[unknown-version], /home/odl/build/controller/opendaylight/config/threadpool-config-impl/pom.xml, line 54, column 15
[WARNING]
[WARNING] It is highly recommended to fix these problems because they threaten the stability of your build.
[WARNING]
[WARNING] For this reason, future Maven versions might no longer support building such malformed projects.
[WARNING]

According to Stack Overflow information [0] (might be outdated) version information included in dependencyManagement does not apply for plugin versions, so importing

-artifacts is not enough.

To fix, either specify plugin version explicitly in every use, or employ pluginManagement somehow.

[0] https://stackoverflow.com/a/11258114