Potential deadlock: frozen threads found

It seems that the following threads have not changed their stack for more than 10 seconds.
These threads are possibly (but not necessarily!) in a deadlock or hung.
Potential deadlock: frozen threads found

Thread X
{quote}
XXXXXXXXXXX-Thread998 [mporhel] Frozen for at least 10s
  org.eclipse.swt.internal.cocoa.OS.objc_msgSend_stret(NSRange, long, long, long) OS.java (native)  
  org.eclipse.swt.internal.cocoa.NSLayoutManager.glyphRangeForTextContainer(NSTextContainer) NSLayoutManager.java:85 
  org.eclipse.swt.graphics.GC.textExtent(String, int) GC.java:4000 
  org.eclipse.swt.graphics.GC.stringExtent(String) GC.java:3933
  org.eclipse.draw2d.FigureUtilities.getStringDimension(String, Font) FigureUtilities.java:125 
  org.eclipse.draw2d.FigureUtilities.getStringExtents(String, Font) FigureUtilities.java:154 
  org.eclipse.sirius.diagram.ui.tools.api.graphical.edit.styles.SimpleStyleConfiguration.fitToText(DNode, SiriusWrapLabel,DefaultSizeNodeFigure) SimpleStyleConfiguration.java:249
  org.eclipse.sirius.diagram.ui.graphical.edit.policies.AirResizableEditPolicy.getAutoSizeCommand(Request) AirResizableEditPolicy.java:94
  org.eclipse.gmf.runtime.diagram.ui.editpolicies.ResizableShapeEditPolicy.getCommand(Request) ResizableShapeEditPolicy.java:133 
  org.eclipse.gef.editparts.AbstractEditPart.getCommand(Request) AbstractEditPart.java:502 
  org.eclipse.gmf.runtime.diagram.ui.editparts.GraphicalEditPart.access$1(GraphicalEditPart, Request) GraphicalEditPart.java:1 
  org.eclipse.gmf.runtime.diagram.ui.editparts.GraphicalEditPart$1.run() GraphicalEditPart.java:482
  org.eclipse.emf.transaction.impl.TransactionalEditingDomainImpl.runExclusive(Runnable) TransactionalEditingDomainImpl.java:328 
  org.eclipse.gmf.runtime.diagram.ui.editparts.GraphicalEditPart.getCommand(Request) GraphicalEditPart.java:477
  org.eclipse.sirius.diagram.ui.edit.api.part.AbstractDiagramNodeEditPart.getCommand(Request) AbstractDiagramNodeEditPart.java:371 
  org.eclipse.gmf.runtime.diagram.ui.actions.internal.AutoSizeAction.getCommand(Request) AutoSizeAction.java:101 
  org.eclipse.gmf.runtime.diagram.ui.actions.DiagramAction.getCommand() DiagramAction.java:161 
  org.eclipse.gmf.runtime.diagram.ui.actions.DiagramAction.calculateEnabled() DiagramAction.java:124 
  org.eclipse.gmf.runtime.diagram.ui.actions.DiagramAction.refresh() DiagramAction.java:114
  org.eclipse.gmf.runtime.common.ui.action.AbstractActionHandler.historyNotification(OperationHistoryEvent) AbstractActionHandler.java:602 
  org.eclipse.core.commands.operations.DefaultOperationHistory$2.run() DefaultOperationHistory.java:868
  org.eclipse.core.runtime.SafeRunner.run(ISafeRunnable) SafeRunner.java:42
  org.eclipse.core.commands.operations.DefaultOperationHistory.notifyListeners(OperationHistoryEvent) DefaultOperationHistory.java:857 
  org.eclipse.core.commands.operations.DefaultOperationHistory.notifyRemoved(IUndoableOperation) DefaultOperationHistory.java:968
  org.eclipse.core.commands.operations.DefaultOperationHistory.internalRemove(IUndoableOperation) DefaultOperationHistory.java:832 
  org.eclipse.core.commands.operations.DefaultOperationHistory.flushUndo(IUndoContext) DefaultOperationHistory.java:599
  org.eclipse.core.commands.operations.DefaultOperationHistory.dispose(IUndoContext, boolean, boolean, boolean) DefaultOperationHistory.java:313 
  org.eclipse.emf.workspace.impl.WorkspaceCommandStackImpl.flush() WorkspaceCommandStackImpl.java:306
  ...
  java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor$Worker) ThreadPoolExecutor.java:1149 
  java.util.concurrent.ThreadPoolExecutor$Worker.run() ThreadPoolExecutor.java:624 
  java.lang.Thread.run() Thread.java:748 
{quote}

UI Thread
{quote}
main Frozen for at least 10s 
  org.eclipse.core.commands.operations.DefaultOperationHistory.getUndoOperation(IUndoContext) DefaultOperationHistory.java:790 
  org.eclipse.core.commands.operations.DefaultOperationHistory.canUndo(IUndoContext) DefaultOperationHistory.java:260
  org.eclipse.ui.operations.UndoActionHandler.shouldBeEnabled() UndoActionHandler.java:92
  org.eclipse.ui.operations.OperationHistoryActionHandler.update() OperationHistoryActionHandler.java:415
  org.eclipse.ui.operations.OperationHistoryActionHandler$HistoryListener.lambda$0() OperationHistoryActionHandler.java:143
  org.eclipse.ui.operations.OperationHistoryActionHandler$HistoryListener$$Lambda$556.run()
  org.eclipse.swt.widgets.RunnableLock.run(Display) RunnableLock.java:37 
  org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(boolean) Synchronizer.java:182 
  org.eclipse.swt.widgets.Display.runAsyncMessages(boolean) Display.java:4034
  org.eclipse.swt.widgets.Display.readAndDispatch() Display.java:3701
  org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run() PartRenderingEngine.java:1150 
  org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm, Runnable) Realm.java:336 
  org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(MApplicationElement, IEclipseContext) PartRenderingEngine.java:1039 
  org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(MApplicationElement) E4Workbench.java:153
  org.eclipse.ui.internal.Workbench.lambda$3(Display, WorkbenchAdvisor, int[]) Workbench.java:680
  org.eclipse.ui.internal.Workbench$$Lambda$15.run() 
  org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm, Runnable) Realm.java:336 
  org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Display, WorkbenchAdvisor) Workbench.java:594
  org.eclipse.ui.PlatformUI.createAndRunWorkbench(Display, WorkbenchAdvisor) PlatformUI.java:148 
  my.Application.start(IApplicationContext) Application.java:103
  org.eclipse.equinox.internal.app.EclipseAppHandle.run(Object) EclipseAppHandle.java:196
  org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(Object) EclipseAppLauncher.java:134
  org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(Object) EclipseAppLauncher.java:104 
  org.eclipse.core.runtime.adaptor.EclipseStarter.run(Object) EclipseStarter.java:388
  org.eclipse.core.runtime.adaptor.EclipseStarter.run(String[], Runnable) EclipseStarter.java:243
  sun.reflect.NativeMethodAccessorImpl.invoke0(Method, Object, Object[]) NativeMethodAccessorImpl.java (native)
  sun.reflect.NativeMethodAccessorImpl.invoke(Object, Object[]) NativeMethodAccessorImpl.java:62 
  sun.reflect.DelegatingMethodAccessorImpl.invoke(Object, Object[]) DelegatingMethodAccessorImpl.java:43 
  java.lang.reflect.Method.invoke(Object, Object[]) Method.java:498
  org.eclipse.equinox.launcher.Main.invokeFramework(String[], URL[]) Main.java:653 
  org.eclipse.equinox.launcher.Main.basicRun(String[]) Main.java:590 
  org.eclipse.equinox.launcher.Main.run(String[]) Main.java:1499 
{quote}