Fix for 179671: [Editor] Avoid duplicate parsing when opening a file

Fixes also bug 185709: [Editor] Empty outline when editor is reused

core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/ReconcileWorkingCopyOperation.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2006 IBM Corporation and others.
+ * Copyright (c) 2000, 2007 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -7,6 +7,7 @@
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
+ *     Anton Leherbauer (Wind River Systems)
  *******************************************************************************/
 package org.eclipse.cdt.internal.core.model;
 
@@ -51,34 +52,24 @@ public class ReconcileWorkingCopyOperation extends CModelOperation {
 		CElementDeltaBuilder deltaBuilder = null;
 	
 		try {
-			// create the delta builder (this remembers the current content of the cu)
+			if (!wasConsistent || forceProblemDetection || fComputeAST) {
-			if (!wasConsistent){
+				// create the delta builder (this remembers the current content of the tu)
 				deltaBuilder = new CElementDeltaBuilder(workingCopy);
 				
 				// update the element infos with the content of the working copy
-				if (fComputeAST) {
 				fAST= workingCopy.makeConsistent(fComputeAST, fMonitor);
-				} else {
+
-					workingCopy.makeConsistent(fMonitor);
-				}
 				deltaBuilder.buildDeltas();
 
 				// register the deltas
-				if (deltaBuilder != null){
+				if (deltaBuilder.delta != null) {
-					if ((deltaBuilder.delta != null) && (deltaBuilder.delta.getAffectedChildren().length > 0)) {
 					addReconcileDelta(workingCopy, deltaBuilder.delta);
 				}
-				}
 
 			}
 	
 			if (fMonitor != null) fMonitor.worked(2);
 			
-			// force problem detection? - if structure was consistent
-			if (forceProblemDetection && wasConsistent){
-				if (fMonitor != null && fMonitor.isCanceled()) return;		
-			}
-			
 		} finally {
 			if (fMonitor != null) fMonitor.done();
 		}

core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/TranslationUnit.java

@@ -490,11 +490,11 @@ public class TranslationUnit extends Openable implements ITranslationUnit {
 	}
 
 	public void makeConsistent(IProgressMonitor monitor, boolean forced) throws CModelException {
-		makeConsistent(false, monitor);
+		makeConsistent(forced, monitor);
 	}
 
 	protected IASTTranslationUnit makeConsistent(boolean computeAST, IProgressMonitor monitor) throws CModelException {
-		if (isConsistent()) {
+		if (!computeAST && isConsistent()) {
 			return null;
 		}
 		

core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/ASTProvider.java

@@ -16,6 +16,7 @@ package org.eclipse.cdt.internal.ui.editor;
 import org.eclipse.core.runtime.Assert;
 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.core.runtime.IStatus;
+import org.eclipse.core.runtime.Status;
 import org.eclipse.ui.IPartListener2;
 import org.eclipse.ui.IWindowListener;
 import org.eclipse.ui.IWorkbenchPart;
@@ -298,6 +299,9 @@ public final class ASTProvider {
 		if (cElement == null)
 			return null;
 		Assert.isTrue(cElement instanceof ITranslationUnit);
+		if (waitFlag == WAIT_ACTIVE_ONLY && !isActive((ITranslationUnit)cElement)) {
+			return null;
+		}
 		return fCache.getAST((ITranslationUnit)cElement, index, waitFlag != WAIT_NO, progressMonitor);
 	}
 
@@ -326,6 +330,9 @@ public final class ASTProvider {
 	public IStatus runOnAST(ICElement cElement, WAIT_FLAG waitFlag, IProgressMonitor monitor,
 			ASTCache.ASTRunnable astRunnable) {
 		Assert.isTrue(cElement instanceof ITranslationUnit);
+		if (waitFlag == WAIT_ACTIVE_ONLY && !isActive((ITranslationUnit)cElement)) {
+			return Status.CANCEL_STATUS;
+		}
 		return fCache.runOnAST((ITranslationUnit)cElement, waitFlag != WAIT_NO, monitor, astRunnable);
 	}
 

core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/CContentOutlinerProvider.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2002, 2006 QNX Software Systems and others.
+ * Copyright (c) 2002, 2007 QNX Software Systems and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -7,6 +7,7 @@
  *
  * Contributors:
  * QNX Software Systems - Initial API and implementation
+ * Anton Leherbauer (Wind River Systems)
  *******************************************************************************/
 package org.eclipse.cdt.internal.ui.editor;
 
@@ -14,6 +15,16 @@ import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
 
+import org.eclipse.jface.util.IPropertyChangeListener;
+import org.eclipse.jface.util.PropertyChangeEvent;
+import org.eclipse.jface.viewers.ISelection;
+import org.eclipse.jface.viewers.IStructuredSelection;
+import org.eclipse.jface.viewers.StructuredSelection;
+import org.eclipse.jface.viewers.TreeViewer;
+import org.eclipse.jface.viewers.Viewer;
+import org.eclipse.ui.IWorkbenchPartSite;
+import org.eclipse.ui.progress.PendingUpdateAdapter;
+
 import org.eclipse.cdt.core.model.CModelException;
 import org.eclipse.cdt.core.model.CoreModel;
 import org.eclipse.cdt.core.model.ElementChangedEvent;
@@ -22,27 +33,13 @@ import org.eclipse.cdt.core.model.ICElementDelta;
 import org.eclipse.cdt.core.model.IElementChangedListener;
 import org.eclipse.cdt.core.model.ISourceRange;
 import org.eclipse.cdt.core.model.ITranslationUnit;
+import org.eclipse.cdt.ui.PreferenceConstants;
+
 import org.eclipse.cdt.internal.core.model.CShiftData;
 import org.eclipse.cdt.internal.core.model.SourceManipulation;
+
 import org.eclipse.cdt.internal.ui.BaseCElementContentProvider;
 import org.eclipse.cdt.internal.ui.util.StringMatcher;
-import org.eclipse.cdt.ui.PreferenceConstants;
-import org.eclipse.core.runtime.IProgressMonitor;
-import org.eclipse.core.runtime.IStatus;
-import org.eclipse.core.runtime.Status;
-import org.eclipse.jface.util.IPropertyChangeListener;
-import org.eclipse.jface.util.PropertyChangeEvent;
-import org.eclipse.jface.viewers.AbstractTreeViewer;
-import org.eclipse.jface.viewers.ISelection;
-import org.eclipse.jface.viewers.IStructuredSelection;
-import org.eclipse.jface.viewers.StructuredSelection;
-import org.eclipse.jface.viewers.TreeViewer;
-import org.eclipse.jface.viewers.Viewer;
-import org.eclipse.ui.IWorkbenchPartSite;
-import org.eclipse.ui.progress.DeferredTreeContentManager;
-import org.eclipse.ui.progress.IElementCollector;
-import org.eclipse.ui.progress.PendingUpdateAdapter;
-import org.eclipse.ui.progress.WorkbenchJob;
 
 /**
  * Manages contents of the outliner.
@@ -64,19 +61,6 @@ public class CContentOutlinerProvider extends BaseCElementContentProvider {
 	/** Filter for files to outline. */
 	private StringMatcher filter = new StringMatcher("*", true, false); //$NON-NLS-1$
 
-	/**
-	 * Remote content manager to retrieve content in the background.
-	 */
-	private DeferredTreeContentManager fManager;
-
-	/**
-	 * We only want to use the DeferredContentManager, the first time
-	 * because the Outliner is initialize in the UI thread.  So to not block
-	 * the UI thread we deferred, after it is not necessary the reconciler is
-	 * running in a separate thread not affecting the UI.
-	 */
-	private boolean fUseContentManager = false;
-
 	public CContentOutlinerProvider(TreeViewer viewer) {
 		this(viewer, null);
 	}
@@ -91,68 +75,6 @@ public class CContentOutlinerProvider extends BaseCElementContentProvider {
 		super(true, true);
 		treeViewer = viewer;
 		setIncludesGrouping(PreferenceConstants.getPreferenceStore().getBoolean(PreferenceConstants.OUTLINE_GROUP_INCLUDES));
-		fManager = createContentManager(viewer, site);
-	}
-	
-	/**
-	 * Subclass of DeferredTreeContentManager used to refresh
-	 * the outline when the "group includes" setting is enabled.
-	 */
-	class DeferredTreeCContentManager extends DeferredTreeContentManager {
-
-		public DeferredTreeCContentManager(AbstractTreeViewer viewer, IWorkbenchPartSite site) {
-			super(CContentOutlinerProvider.this, viewer, site);
-		}
-
-		public DeferredTreeCContentManager(AbstractTreeViewer viewer) {
-			super(CContentOutlinerProvider.this, viewer);
-		}
-		
-	    protected IElementCollector createElementCollector(final Object parent,
-	            final PendingUpdateAdapter placeholder) {
-	    	
-	    	// Return a special element collector when the parent
-	    	// is the translation unit. In that case we need to
-	    	// refresh the outline when all the content has become
-	    	// available.
-	    	if (!(parent instanceof ITranslationUnit)) {
-	    		return super.createElementCollector(parent, placeholder);
-	    	}
-	        return new IElementCollector() {
-		            public void add(Object element, IProgressMonitor monitor) {
-	                add(new Object[] { element }, monitor);
-	            }
-
-	            public void add(Object[] elements, IProgressMonitor monitor) {
-	                addChildren(parent, elements, monitor);
-	            }
-
-	            public void done() {
-	            	runClearPlaceholderJob(placeholder);
-	            	// runClearPlaceholderJob uses a WorkbenchJob and contentUpdated
-	            	// executes via asyncExec(). There can be race conditions if we
-	            	// don't wrap contentUpdated in a job.
-	            	if (CContentOutlinerProvider.this.fIncludesGrouping) {
-	            		WorkbenchJob job = new WorkbenchJob("") { //$NON-NLS-1$
-	            			
-	            			public IStatus runInUIThread(IProgressMonitor monitor) {
-	            				contentUpdated();
-	            				return Status.OK_STATUS;
-	            			}
-	            		};
-	            		job.setSystem(true);
-	            		job.schedule();
-	            	}
-	            }
-	        };	
-	    }
-	}
-
-	protected DeferredTreeContentManager createContentManager(TreeViewer viewer, IWorkbenchPartSite site) {
-		if (site == null) {
-			return new DeferredTreeCContentManager(viewer);
-		}
-		return new DeferredTreeCContentManager(viewer, site);
 	}
 
 	/**
@@ -229,37 +151,30 @@ public class CContentOutlinerProvider extends BaseCElementContentProvider {
 			PreferenceConstants.getPreferenceStore().removePropertyChangeListener(fPropertyListener);
 			fPropertyListener = null;
 		}
-		if (root != null) {
-			fManager.cancel(root);
-		}
 	}
 
-	/**
+	/*
-	 * @see org.eclipse.jface.viewers.IContentProvider#inputChanged(org.eclipse.jface.viewers.Viewer,
+	 * @see org.eclipse.cdt.internal.ui.BaseCElementContentProvider#inputChanged(org.eclipse.jface.viewers.Viewer, java.lang.Object, java.lang.Object)
-	 *      java.lang.Object, java.lang.Object)
 	 */
 	public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
 		boolean isTU = newInput instanceof ITranslationUnit;
 
-		if (isTU && fListener == null) {
+		if (isTU) {
-			fUseContentManager = true;
-			if (root != null) {
-				fManager.cancel(root);
-			}
 			root = (ITranslationUnit) newInput;
-			fListener = new ElementChangedListener();
+			if (fListener == null) {
+				fListener= new ElementChangedListener();
 				CoreModel.getDefault().addElementChangedListener(fListener);
-			fPropertyListener = new PropertyListener();
+				fPropertyListener= new PropertyListener();
-			PreferenceConstants.getPreferenceStore().addPropertyChangeListener(
+				PreferenceConstants.getPreferenceStore().addPropertyChangeListener(fPropertyListener);
-					fPropertyListener);
-		} else if (!isTU && fListener != null) {
-			fUseContentManager = false;
-			CoreModel.getDefault().removeElementChangedListener(fListener);
-			fListener = null;
-			root = null;
-			if (oldInput != null) {
-				fManager.cancel(oldInput);
 			}
+		} else {
+			if (fListener != null) {
+				CoreModel.getDefault().removeElementChangedListener(fListener);
+				PreferenceConstants.getPreferenceStore().removePropertyChangeListener(fPropertyListener);
+				fListener= null;
+				fPropertyListener= null;
+			}
+			root= null;
 		}
 	}
 
@@ -269,9 +184,11 @@ public class CContentOutlinerProvider extends BaseCElementContentProvider {
 	public Object[] getChildren(Object element) {
 		Object[] children = null;
 		// Use the deferred manager for the first time (when parsing)
-		if (fUseContentManager && element instanceof ITranslationUnit) {
+		if (element instanceof ITranslationUnit) {
-			children = fManager.getChildren(element);
+			ITranslationUnit unit= (ITranslationUnit)element;
-			fUseContentManager = false;
+			if (!unit.isOpen()) {
+				children= new Object[] { new PendingUpdateAdapter() };
+			}
 		}
 		if (children == null) {
 			children = super.getChildren(element);
@@ -292,9 +209,6 @@ public class CContentOutlinerProvider extends BaseCElementContentProvider {
 	 * @see org.eclipse.jface.viewers.ITreeContentProvider#hasChildren(java.lang.Object)
 	 */
 	public boolean hasChildren(Object element) {
-		if (fUseContentManager) {
-			return fManager.mayHaveChildren(element);
-		}
 		return super.hasChildren(element);
 	}
 

core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/CEditor.java

@@ -74,6 +74,7 @@ import org.eclipse.jface.text.source.IAnnotationModel;
 import org.eclipse.jface.text.source.ICharacterPairMatcher;
 import org.eclipse.jface.text.source.IOverviewRuler;
 import org.eclipse.jface.text.source.ISourceViewer;
+import org.eclipse.jface.text.source.ISourceViewerExtension2;
 import org.eclipse.jface.text.source.IVerticalRuler;
 import org.eclipse.jface.text.source.SourceViewerConfiguration;
 import org.eclipse.jface.text.source.projection.ProjectionAnnotationModel;
@@ -138,7 +139,6 @@ import org.eclipse.cdt.core.IPositionConverter;
 import org.eclipse.cdt.core.dom.ast.IASTTranslationUnit;
 import org.eclipse.cdt.core.dom.ast.gnu.cpp.GPPLanguage;
 import org.eclipse.cdt.core.formatter.DefaultCodeFormatterConstants;
-import org.eclipse.cdt.core.index.IIndex;
 import org.eclipse.cdt.core.model.CModelException;
 import org.eclipse.cdt.core.model.ICElement;
 import org.eclipse.cdt.core.model.ICProject;
@@ -156,8 +156,6 @@ import org.eclipse.cdt.ui.actions.OpenViewActionGroup;
 import org.eclipse.cdt.ui.text.ICPartitions;
 import org.eclipse.cdt.ui.text.folding.ICFoldingStructureProvider;
 
-import org.eclipse.cdt.internal.corext.util.SimplePositionTracker;
-
 import org.eclipse.cdt.internal.ui.CPluginImages;
 import org.eclipse.cdt.internal.ui.ICHelpContextIds;
 import org.eclipse.cdt.internal.ui.IContextMenuConstants;
@@ -186,9 +184,9 @@ import org.eclipse.cdt.internal.ui.util.CUIHelp;
 
 
 /**
- * C specific text editor.
+ * C/C++ source editor.
  */
-public class CEditor extends TextEditor implements ISelectionChangedListener, IReconcilingParticipant, ICReconcilingListener {
+public class CEditor extends TextEditor implements ISelectionChangedListener, ICReconcilingListener {
 
 	class AdaptedSourceViewer extends CSourceViewer  {
 
@@ -1159,7 +1157,22 @@ public class CEditor extends TextEditor implements ISelectionChangedListener, IR
 	 * @see org.eclipse.ui.texteditor.AbstractTextEditor#doSetInput(org.eclipse.ui.IEditorInput)
 	 */
 	protected void doSetInput(IEditorInput input) throws CoreException {
+		boolean reuse= getEditorInput() != null;
+
 		super.doSetInput(input);
+
+		if (reuse) {
+			// in case language changed, need to reconfigure the viewer
+			ISourceViewer viewer= getSourceViewer();
+			if (viewer instanceof ISourceViewerExtension2) {
+				ISourceViewerExtension2 viewerExt2= (ISourceViewerExtension2)viewer;
+				viewerExt2.unconfigure();
+				CSourceViewerConfiguration cConfig= (CSourceViewerConfiguration)getSourceViewerConfiguration();
+				cConfig.resetScanners();
+				viewer.configure(cConfig);
+			}
+		}
+		
 		setOutlinePageInput(fOutlinePage, input);
 
 		if (fProjectionModelUpdater != null) {
@@ -1548,7 +1561,7 @@ public class CEditor extends TextEditor implements ISelectionChangedListener, IR
      * @param element Element to select.
 	 */
     public void setSelection(ICElement element) {
-		if (element instanceof ISourceReference) {
+		if (element instanceof ISourceReference && !(element instanceof ITranslationUnit)) {
 			ISourceReference reference = (ISourceReference) element;
 			// set hightlight range
 			setSelection(reference, true);
@@ -2471,51 +2484,6 @@ public class CEditor extends TextEditor implements ISelectionChangedListener, IR
 		}
 	}
 
-	/*
-	 * @see org.eclipse.cdt.internal.ui.editor.IReconcilingParticipant#reconciled()
-	 */
-	public void reconciled(boolean somethingHasChanged) {
-		if (getSourceViewer() == null || getSourceViewer().getTextWidget() == null) {
-			return;
-		}
-		// this method must be called in a background thread
-		assert getSourceViewer().getTextWidget().getDisplay().getThread() != Thread.currentThread();
-		
-		if (fReconcilingListeners.size() > 0) {
-			// create AST and notify ICReconcilingListeners
-			ICElement cElement= getInputCElement();
-			if (cElement == null) {
-				return;
-			}
-			
-			aboutToBeReconciled();
-
-			// track changes to the document while parsing
-			IDocument doc= getDocumentProvider().getDocument(getEditorInput());
-			SimplePositionTracker positionTracker= new SimplePositionTracker();
-			positionTracker.startTracking(doc);
-			
-			ASTProvider astProvider= CUIPlugin.getDefault().getASTProvider();
-			IIndex index;
-			try {
-				index = CCorePlugin.getIndexManager().getIndex(cElement.getCProject());
-				index.acquireReadLock();
-			} catch (CoreException e) {
-				CUIPlugin.getDefault().log(e);
-				return;
-			} catch (InterruptedException e) {
-				return;
-			}
-			try {
-				IASTTranslationUnit ast= astProvider.createAST(cElement, index, null);
-				reconciled(ast, positionTracker, null);
-			} finally {
-				index.releaseReadLock();
-				positionTracker.stopTracking();
-			}
-		}
-	}
-	
 	/*
 	 * @see org.eclipse.ui.texteditor.AbstractDecoratedTextEditor#collectContextMenuPreferencePages()
 	 */

core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/IReconcilingParticipant.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2004, 2006 IBM Corporation and others.
+ * Copyright (c) 2004, 2007 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -15,6 +15,7 @@ package org.eclipse.cdt.internal.ui.editor;
 
 /**
  * Interface of an object participating in reconciling.
+ * @deprecated in favour of {@link org.eclipse.cdt.internal.ui.text.ICReconcilingListener}
  */
 public interface IReconcilingParticipant {
 	

core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/text/CReconcilingStrategy.java

@@ -33,8 +33,6 @@ import org.eclipse.cdt.ui.IWorkingCopyManager;
 
 import org.eclipse.cdt.internal.core.model.CModelManager;
 
-import org.eclipse.cdt.internal.ui.editor.IReconcilingParticipant;
-
 
 public class CReconcilingStrategy implements IReconcilingStrategy, IReconcilingStrategyExtension {
 
@@ -73,6 +71,7 @@ public class CReconcilingStrategy implements IReconcilingStrategy, IReconcilingS
 
 	/*
 	 * @see org.eclipse.jface.text.reconciler.IReconcilingStrategy#reconcile(org.eclipse.jface.text.reconciler.DirtyRegion, org.eclipse.jface.text.IRegion)
+	 * Called for incremental reconciler only - currently not used (no shift deltas)
 	 */
 	public void reconcile(DirtyRegion dirtyRegion, IRegion region) {
 		// consistent data needs not further checks !  
@@ -114,13 +113,13 @@ public class CReconcilingStrategy implements IReconcilingStrategy, IReconcilingS
 	}
 	
 	private void reconcile(final boolean initialReconcile) {
+		boolean computeAST= fEditor instanceof ICReconcilingListener;
 		IASTTranslationUnit ast= null;
 		IWorkingCopy workingCopy= fManager.getWorkingCopy(fEditor.getEditorInput());
 		if (workingCopy == null) {
 			return;
 		}
 		try {
-			final boolean computeAST= initialReconcile || CUIPlugin.getDefault().getASTProvider().isActive(workingCopy);
 			// reconcile
 			synchronized (workingCopy) {
 				ast= workingCopy.reconcile(computeAST, true, fProgressMonitor);
@@ -131,18 +130,10 @@ public class CReconcilingStrategy implements IReconcilingStrategy, IReconcilingS
 			IStatus status= new Status(IStatus.ERROR, CUIPlugin.PLUGIN_ID, IStatus.OK, "Error in CDT UI during reconcile", e);  //$NON-NLS-1$
 			CUIPlugin.getDefault().log(status);
 		} finally {
-			if (fEditor instanceof ICReconcilingListener) {
+			if (computeAST) {
 				IIndex index= null;
 				if (ast != null) {
 					index= ast.getIndex();
-					if (index != null) {
-						try {
-							index.acquireReadLock();
-						} catch (InterruptedException exc) {
-							ast= null;
-							index= null;
-						}
-					}
 				}
 				try {
 					((ICReconcilingListener)fEditor).reconciled(ast, null, fProgressMonitor);
@@ -152,13 +143,6 @@ public class CReconcilingStrategy implements IReconcilingStrategy, IReconcilingS
 					}
 				}
 			}
-			if (fProgressMonitor != null && fProgressMonitor.isCanceled()) {
-				return;
-			}
-			if (ast == null && fEditor instanceof IReconcilingParticipant && workingCopy.exists()) {
-				IReconcilingParticipant p= (IReconcilingParticipant) fEditor;
-				p.reconciled(true);
-			}
 		}
  	}
 

core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/text/folding/DefaultCFoldingStructureProvider.java

@@ -58,9 +58,7 @@ import org.eclipse.cdt.core.dom.ast.IASTPreprocessorStatement;
 import org.eclipse.cdt.core.dom.ast.IASTTranslationUnit;
 import org.eclipse.cdt.core.model.CModelException;
 import org.eclipse.cdt.core.model.CoreModel;
-import org.eclipse.cdt.core.model.ElementChangedEvent;
 import org.eclipse.cdt.core.model.ICElement;
-import org.eclipse.cdt.core.model.ICElementDelta;
 import org.eclipse.cdt.core.model.IElementChangedListener;
 import org.eclipse.cdt.core.model.IMember;
 import org.eclipse.cdt.core.model.IParent;
@@ -104,13 +102,16 @@ public class DefaultCFoldingStructureProvider implements ICFoldingStructureProvi
 		 * @see org.eclipse.cdt.internal.ui.text.ICReconcilingListener#reconciled(org.eclipse.cdt.core.dom.ast.IASTTranslationUnit, org.eclipse.cdt.core.IPositionConverter, org.eclipse.core.runtime.IProgressMonitor)
 		 */
 		public void reconciled(IASTTranslationUnit ast, IPositionConverter positionTracker, IProgressMonitor progressMonitor) {
-			if (fInput == null || ast == null || fReconciling) {
+			if (fInput == null || fReconciling) {
+				return;
+			}
+			if (fPreprocessorBranchFoldingEnabled && ast == null) {
 				return;
 			}
 			fReconciling= true;
 			try {
-				FoldingStructureComputationContext ctx= createContext(fInitialASTReconcile);
+				FoldingStructureComputationContext ctx= createContext(fInitialReconcilePending);
-				fInitialASTReconcile= false;
+				fInitialReconcilePending= false;
 				if (fPreprocessorBranchFoldingEnabled) {
 					ctx.fAST= ast;
 					ctx.fASTPositionConverter= positionTracker;
@@ -350,44 +351,6 @@ public class DefaultCFoldingStructureProvider implements ICFoldingStructureProvi
 	}
 
 	
-	private class ElementChangedListener implements IElementChangedListener {
-		
-		/*
-		 * @see org.eclipse.cdt.core.IElementChangedListener#elementChanged(org.eclipse.cdt.core.ElementChangedEvent)
-		 */
-		public void elementChanged(ElementChangedEvent e) {
-			ICElementDelta delta= findElement(fInput, e.getDelta());
-			if (delta != null)
-	            update(createContext(false));
-		}
-		
-		private ICElementDelta findElement(ICElement target, ICElementDelta delta) {
-			
-			if (delta == null || target == null)
-				return null;
-			
-			ICElement element= delta.getElement();
-			
-			if (element.getElementType() > ICElement.C_UNIT)
-				return null;
-			
-			if (target.equals(element))
-				return delta;				
-			
-			ICElementDelta[] children= delta.getAffectedChildren();
-			if (children == null || children.length == 0)
-				return null;
-				
-			for (int i= 0; i < children.length; i++) {
-				ICElementDelta d= findElement(target, children[i]);
-				if (d != null)
-					return d;
-			}
-			
-			return null;
-		}		
-	}
-	
 	/**
 	 * Projection position that will return two foldable regions: one folding away
 	 * the region from after the '/*' to the beginning of the content, the other
@@ -705,7 +668,7 @@ public class DefaultCFoldingStructureProvider implements ICFoldingStructureProvi
 	private boolean fCommentFoldingEnabled= true;
 
 	private ICReconcilingListener fReconilingListener;
-	boolean fInitialASTReconcile= true;
+	boolean fInitialReconcilePending= true;
 
 
 	/**
@@ -781,15 +744,10 @@ public class DefaultCFoldingStructureProvider implements ICFoldingStructureProvi
 		handleProjectionDisabled();
 
 		if (fEditor instanceof CEditor) {
-			fInitialASTReconcile= true;
+			fInitialReconcilePending= true;
 			initialize();
-			if (fPreprocessorBranchFoldingEnabled || fCommentFoldingEnabled) {
 			fReconilingListener= new PreprocessorBranchesReconciler();
 			((CEditor)fEditor).addReconcileListener(fReconilingListener);
-			} else {
-				fElementListener= new ElementChangedListener();
-				CoreModel.getDefault().addElementChangedListener(fElementListener);
-			}
 		}
 	}
 
@@ -1087,11 +1045,6 @@ public class DefaultCFoldingStructureProvider implements ICFoldingStructureProvi
 				// ignore
 			}
 		}
-		IParent parent= (IParent) fInput;
-		try {
-			computeFoldingStructure(parent.getChildren(), ctx);
-		} catch (CModelException x) {
-		}
 		if (fPreprocessorBranchFoldingEnabled) {
 			IASTTranslationUnit ast= ctx.getAST();
 			if (ast == null) {
@@ -1101,19 +1054,26 @@ public class DefaultCFoldingStructureProvider implements ICFoldingStructureProvi
 						if (ast != null) {
 							ctx.fAST= ast;
 							ctx.fASTPositionConverter= null;
-							fInitialASTReconcile= false;
+							fInitialReconcilePending= false;
 							computeFoldingStructure(ast, ctx);
 						}
 						return Status.OK_STATUS;
 					}
 				});
-				if (!status.isOK()) {
+				if (status.matches(IStatus.ERROR)) {
 					CUIPlugin.getDefault().log(status);
 				}
 			} else {
 				computeFoldingStructure(ast, ctx);
 			}
 		}
+		if (!fInitialReconcilePending) {
+			IParent parent= (IParent) fInput;
+			try {
+				computeFoldingStructure(parent.getChildren(), ctx);
+			} catch (CModelException x) {
+			}
+		}
 	}
 
 	/**