diff --git a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/CConfigBasedDescriptor.java b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/CConfigBasedDescriptor.java
index 1f044c061e2..c8ca56bfca9 100644
--- a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/CConfigBasedDescriptor.java
+++ b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/CConfigBasedDescriptor.java
@@ -300,7 +300,8 @@ public class CConfigBasedDescriptor implements ICDescriptor {
 	}
 
 	public void saveProjectData() throws CoreException {
-		CConfigBasedDescriptorManager.getInstance().reconsile(this, fCfgDes.getProjectDescription());
+		if(CConfigBasedDescriptorManager.getInstance().reconsile(this, fCfgDes.getProjectDescription()))
+			fIsDirty = true;
 		
 		checkApply();
 	}