NPE in ConcurrentHashMap.removeAll()

FULL PRODUCT VERSION :


ADDITIONAL OS VERSION INFORMATION :
$ java -version
java version "9-ea"
Java(TM) SE Runtime Environment (build 9-ea+129)
Java HotSpot(TM) 64-Bit Server VM (build 9-ea+129, mixed mode)

OS name: "mac os x", version: "10.11.6", arch: "x86_64", family: "mac"


A DESCRIPTION OF THE PROBLEM :
10:39:47,069 ERROR [org.jboss.msc.service.fail] (MSC service thread 1-6) MSC000001: Failed to start service jboss.deployment.unit."atom-test.war".WeldStartService: org.jboss.msc.service.StartException in service jboss.deployment.unit."atom-test.war".WeldStartService: Failed to start service
at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1904)
at java.util.concurrent.ThreadPoolExecutor.runWorker(java.base@9-ea/ThreadPoolExecutor.java:1158)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(java.base@9-ea/ThreadPoolExecutor.java:632)
at java.lang.Thread.run(java.base@9-ea/Thread.java:843)
Caused by: java.lang.NullPointerException
at java.util.concurrent.ConcurrentHashMap$CollectionView.removeAll(java.base@9-ea/ConcurrentHashMap.java:4569)
at java.util.concurrent.ConcurrentHashMap$KeySetView.removeAll(java.base@9-ea/ConcurrentHashMap.java:4608)
at java.util.Collections$SetFromMap.removeAll(java.base@9-ea/Collections.java:5486)
at org.jboss.weld.bootstrap.BeanDeployerEnvironment.removeAnnotatedTypes(BeanDeployerEnvironment.java:166)
at org.jboss.weld.bootstrap.BeanDeployer.processAnnotatedTypes(BeanDeployer.java:178)
at org.jboss.weld.bootstrap.BeanDeployment.createTypes(BeanDeployment.java:224)
at org.jboss.weld.bootstrap.WeldStartup.startInitialization(WeldStartup.java:383)
at org.jboss.weld.bootstrap.WeldBootstrap.startInitialization(WeldBootstrap.java:76)
at org.jboss.as.weld.WeldStartService.start(WeldStartService.java:94)
at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1948)
at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1881)



REPRODUCIBILITY :
This bug can be reproduced always.