java.util.ConcurrentModificationException
   at org.openide.util.WeakSet$SharedKeyWeakHashMap$HashIterator.nextEntry(WeakSet.java:1010)
   at org.openide.util.WeakSet$SharedKeyWeakHashMap$KeyIterator.next(WeakSet.java:1052)
   at org.netbeans.modules.cnd.api.toolchain.ui.ToolsPanelSupport.fireCodeAssistanceChange(ToolsPanelSupport.java:187)
   at org.netbeans.modules.cnd.toolchain.compilerset.ToolchainValidator.applyChanges(ToolchainValidator.java:108)
   at org.netbeans.modules.cnd.toolchain.compilerset.FixCodeAssistancePanel$1.actionPerformed(FixCodeAssistancePanel.java:97)
   at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2028)
   at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2351)
   at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
   at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
   at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
   at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:272)
   at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:272)
   at java.awt.Component.processMouseEvent(Component.java:6374)
   at javax.swing.JComponent.processMouseEvent(JComponent.java:3267)
   at java.awt.Component.processEvent(Component.java:6139)
   at java.awt.Container.processEvent(Container.java:2085)
   at java.awt.Component.dispatchEventImpl(Component.java:4736)
   at java.awt.Container.dispatchEventImpl(Container.java:2143)
   at java.awt.Component.dispatchEvent(Component.java:4566)
   at java.awt.LightweightDispatcher.retargetMouseEvent(LightweightDispatcher.java:4621)
   at java.awt.LightweightDispatcher.processMouseEvent(LightweightDispatcher.java:4282)
   at java.awt.LightweightDispatcher.dispatchEvent(LightweightDispatcher.java:4212)
   at java.awt.Container.dispatchEventImpl(Container.java:2129)
   at java.awt.Window.dispatchEventImpl(Window.java:2478)
   at java.awt.Component.dispatchEvent(Component.java:4566)
   at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:680)
   at java.awt.EventQueue.access$000(EventQueue.java:86)
   at java.awt.EventQueue$1.run(EventQueue.java:639)
   at java.awt.EventQueue$1.run(EventQueue.java:637)
   at java.security.AccessController.doPrivileged(AccessController.java:0)
   at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
   at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:98)
   at java.awt.EventQueue$2.run(EventQueue.java:653)
   at java.awt.EventQueue$2.run(EventQueue.java:651)
   at java.security.AccessController.doPrivileged(AccessController.java:0)
   at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:650)
   at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:148)
   at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:296)
   at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:211)
   at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:201)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:196)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:188)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)