java.io.IOException: Not an NBM project in /home/ondra/sources/netbeans/core-main/core.startup.base
   at org.netbeans.modules.apisupport.project.universe.ModuleList$2.run(ModuleList.java:213)
   at org.netbeans.modules.apisupport.project.universe.ModuleList$2.run(ModuleList.java:205)
   at org.netbeans.modules.apisupport.project.universe.ModuleList$1.run(ModuleList.java:185)
   at org.netbeans.modules.apisupport.project.universe.ModuleList$1.run(ModuleList.java:181)
   at org.netbeans.modules.openide.util.DefaultMutexImplementation.readAccess(DefaultMutexImplementation.java:252)
   at org.openide.util.Mutex.readAccess(Mutex.java:250)
   at org.netbeans.modules.apisupport.project.universe.ModuleList.runProtected(ModuleList.java:181)
   at org.netbeans.modules.apisupport.project.universe.ModuleList.getModuleList(ModuleList.java:205)
   at org.netbeans.modules.apisupport.project.NbModuleProject.getModuleList(NbModuleProject.java:613)
   at org.netbeans.modules.apisupport.project.queries.ClassPathProviderImpl$FxPathImpl.getResources(ClassPathProviderImpl.java:592)
   at org.netbeans.modules.java.classpath.ProxyClassPathImplementation.getResources(ProxyClassPathImplementation.java:94)
   at org.netbeans.api.java.classpath.ClassPath.entries(ClassPath.java:369)
   at org.netbeans.modules.java.source.classpath.CacheClassPath.getResources(CacheClassPath.java:165)
   at org.netbeans.api.java.classpath.ClassPath$SPIListener.propertyChange(ClassPath.java:1228)
   at org.openide.util.WeakListenerImpl$PropertyChange.propertyChange(WeakListenerImpl.java:215)
   at java.beans.PropertyChangeSupport.fire(PropertyChangeSupport.java:335)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:327)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:263)
   at org.netbeans.modules.java.source.classpath.CacheClassPath.propertyChange(CacheClassPath.java:126)
   at org.openide.util.WeakListenerImpl$PropertyChange.propertyChange(WeakListenerImpl.java:215)
   at java.beans.PropertyChangeSupport.fire(PropertyChangeSupport.java:335)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:327)
   at org.netbeans.api.java.classpath.ClassPath.firePropertyChange(ClassPath.java:697)
   at org.netbeans.api.java.classpath.ClassPath$SPIListener.propertyChange(ClassPath.java:1212)
   at org.openide.util.WeakListenerImpl$PropertyChange.propertyChange(WeakListenerImpl.java:215)
   at org.netbeans.modules.java.classpath.ProxyClassPathImplementation$DelegatesListener.propertyChange(ProxyClassPathImplementation.java:146)
   at org.openide.util.WeakListenerImpl$PropertyChange.propertyChange(WeakListenerImpl.java:215)
   at java.beans.PropertyChangeSupport.fire(PropertyChangeSupport.java:335)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:327)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:263)
   at org.netbeans.modules.apisupport.project.queries.ClassPathProviderImpl$FxPathImpl.propertyChange(ClassPathProviderImpl.java:633)
   at java.beans.PropertyChangeSupport.fire(PropertyChangeSupport.java:335)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:327)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:263)
   at org.netbeans.modules.apisupport.project.Evaluator.propertyChange(Evaluator.java:267)
   at java.beans.PropertyChangeSupport.fire(PropertyChangeSupport.java:335)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:327)
   at org.netbeans.spi.project.support.ant.SequentialPropertyEvaluator.stateChanged(SequentialPropertyEvaluator.java:208)
   at org.openide.util.WeakListenerImpl$Change.stateChanged(WeakListenerImpl.java:356)
   at org.openide.util.ChangeSupport.fireChange(ChangeSupport.java:133)
   at org.openide.util.ChangeSupport.fireChange(ChangeSupport.java:119)
   at org.netbeans.spi.project.support.ant.ProjectProperties$PP$2.run(ProjectProperties.java:390)
   at org.netbeans.spi.project.support.ant.ProjectProperties$PP$2.run(ProjectProperties.java:388)
   at org.netbeans.modules.openide.util.DefaultMutexImplementation.readAccess(DefaultMutexImplementation.java:252)
   at org.openide.util.Mutex.readAccess(Mutex.java:218)
   at org.netbeans.spi.project.support.ant.ProjectProperties$PP$3.run(ProjectProperties.java:404)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1425)
   at org.netbeans.modules.openide.util.GlobalLookup.execute(GlobalLookup.java:59)
   at org.openide.util.lookup.Lookups.executeWith(Lookups.java:294)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2038)