diff --git a/build/org.eclipse.cdt.make.core/src/org/eclipse/cdt/make/internal/core/scannerconfig/DiscoveredPathManager.java b/build/org.eclipse.cdt.make.core/src/org/eclipse/cdt/make/internal/core/scannerconfig/DiscoveredPathManager.java
index 58c9a480b7a..a86d0413201 100644
--- a/build/org.eclipse.cdt.make.core/src/org/eclipse/cdt/make/internal/core/scannerconfig/DiscoveredPathManager.java
+++ b/build/org.eclipse.cdt.make.core/src/org/eclipse/cdt/make/internal/core/scannerconfig/DiscoveredPathManager.java
@@ -125,7 +125,7 @@ public class DiscoveredPathManager implements IDiscoveredPathManager, IResourceC
      * @see org.eclipse.cdt.make.core.scannerconfig.IDiscoveredPathManager#updateDiscoveredInfo(org.eclipse.cdt.make.core.scannerconfig.IDiscoveredPathManager.IDiscoveredPathInfo, java.util.List)
      */
     public void updateDiscoveredInfo(IDiscoveredPathInfo info, List changedResources) throws CoreException {
-		if (fDiscoveredMap.get(info.getProject()) != info) {
+		if (fDiscoveredMap.get(info.getProject()) != null) {
             IDiscoveredScannerInfoSerializable serializable = info.getSerializable();
 			if (serializable != null) {
                 IProject project = info.getProject();
diff --git a/build/org.eclipse.cdt.make.core/src/org/eclipse/cdt/make/internal/core/scannerconfig2/PerFileSICollector.java b/build/org.eclipse.cdt.make.core/src/org/eclipse/cdt/make/internal/core/scannerconfig2/PerFileSICollector.java
index 87d0d03add1..c053134d392 100644
--- a/build/org.eclipse.cdt.make.core/src/org/eclipse/cdt/make/internal/core/scannerconfig2/PerFileSICollector.java
+++ b/build/org.eclipse.cdt.make.core/src/org/eclipse/cdt/make/internal/core/scannerconfig2/PerFileSICollector.java
@@ -417,8 +417,12 @@ public class PerFileSICollector implements IScannerInfoCollector2, IScannerInfoC
                 // update scanner configuration
 //                MakeCorePlugin.getDefault().getDiscoveryManager().
 //                        updateDiscoveredInfo(createPathInfoObject(), siChangedForFileList);
+                IDiscoveredPathInfo pathInfo = MakeCorePlugin.getDefault().getDiscoveryManager().getDiscoveredInfo(project);
+                if (!(pathInfo instanceof IPerFileDiscoveredPathInfo)) {
+                	pathInfo = createPathInfoObject();
+                }
                 MakeCorePlugin.getDefault().getDiscoveryManager().
-                		updateDiscoveredInfo(createPathInfoObject(), new ArrayList(siChangedForFileMap.keySet()));
+                		updateDiscoveredInfo(pathInfo, new ArrayList(siChangedForFileMap.keySet()));
                 monitor.worked(50);
             } catch (CoreException e) {
                 MakeCorePlugin.log(e);