NPE in io.quarkus:quarkus-maven-plugin:0.12.0:build

[hwellmann]

quarkus-maven-plugin:build fails with a NullPointerException:

[ERROR] Failed to execute goal io.quarkus:quarkus-maven-plugin:0.12.0:build (default) on project kaiserkai-rest-impl: Failed to build a runnable JAR: Failed to build a runner jar: Failed to augment application classes: Build failure: Build failed due to errors
[ERROR]         [error]: Build step io.quarkus.arc.deployment.ArcAnnotationProcessor#build threw an exception: java.lang.NullPointerException

The detailed stack trace is:

Caused by: java.lang.NullPointerException
    at io.quarkus.arc.processor.Beans.hasQualifier (Beans.java:405)
    at io.quarkus.arc.processor.BeanDeployment.findDisposer (BeanDeployment.java:694)
    at io.quarkus.arc.processor.BeanDeployment.findBeans (BeanDeployment.java:635)
    at io.quarkus.arc.processor.BeanDeployment.<init> (BeanDeployment.java:136)
    at io.quarkus.arc.processor.BeanProcessor.process (BeanProcessor.java:150)
    at io.quarkus.arc.deployment.ArcAnnotationProcessor.build (ArcAnnotationProcessor.java:237)
    at sun.reflect.NativeMethodAccessorImpl.invoke0 (Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke (NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke (DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke (Method.java:498)
    at io.quarkus.deployment.ExtensionLoader$1.execute (ExtensionLoader.java:506)
    at org.jboss.builder.BuildContext.run (BuildContext.java:413)
    at org.jboss.threads.ContextClassLoaderSavingRunnable.run (ContextClassLoaderSavingRunnable.java:35)
    at org.jboss.threads.EnhancedQueueExecutor.safeRun (EnhancedQueueExecutor.java:1998)
    at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.doRunTask (EnhancedQueueExecutor.java:1525)
    at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.run (EnhancedQueueExecutor.java:1416)
    at java.lang.Thread.run (Thread.java:748)
    at org.jboss.threads.JBossThread.run (JBossThread.java:479)

I don't fully understand what's going on here, but there seems to be a broken API contract: io.quarkus.arc.processor.Beans.hasQualifier(ClassInfo, AnnotationInstance, Collection<AnnotationInstance>) expects the third argument to be non-null, whereas BeanDeployment.findDisposer() calls it with a null value.