diff --git a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/CConfigBasedDescriptorManager.java b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/CConfigBasedDescriptorManager.java
index 88238aebabc..4ec0d5f1d48 100644
--- a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/CConfigBasedDescriptorManager.java
+++ b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/CConfigBasedDescriptorManager.java
@@ -324,7 +324,7 @@ public class CConfigBasedDescriptorManager implements ICDescriptorManager {
 		dr = getLoaddedDescriptor(des);
 		if(dr == null){
 			dr = loadDescriptor(des);
-			if(dr != null){
+			if(dr != null && !des.isLoadding()){
 				setLoaddedDescriptor(des, dr);
 			}
 		}