diff --git a/core/org.eclipse.cdt.core/model/org/eclipse/cdt/core/settings/model/ACSettingEntry.java b/core/org.eclipse.cdt.core/model/org/eclipse/cdt/core/settings/model/ACSettingEntry.java
index ff509a828d9..37420be10a1 100644
--- a/core/org.eclipse.cdt.core/model/org/eclipse/cdt/core/settings/model/ACSettingEntry.java
+++ b/core/org.eclipse.cdt.core/model/org/eclipse/cdt/core/settings/model/ACSettingEntry.java
@@ -11,6 +11,7 @@
 package org.eclipse.cdt.core.settings.model;
 
 import org.eclipse.cdt.core.settings.model.util.LanguageSettingEntriesSerializer;
+import org.eclipse.cdt.internal.core.SafeStringInterner;
 
 
 
@@ -19,7 +20,7 @@ public abstract class ACSettingEntry implements ICSettingEntry {
 	String fName;
 	
 	ACSettingEntry(String name, int flags){
-		fName = name;
+		fName = SafeStringInterner.safeIntern(name);
 		fFlags = flags;
 	}
 
diff --git a/core/org.eclipse.cdt.core/model/org/eclipse/cdt/core/settings/model/CMacroEntry.java b/core/org.eclipse.cdt.core/model/org/eclipse/cdt/core/settings/model/CMacroEntry.java
index 34e9a8b3818..451efd313d8 100644
--- a/core/org.eclipse.cdt.core/model/org/eclipse/cdt/core/settings/model/CMacroEntry.java
+++ b/core/org.eclipse.cdt.core/model/org/eclipse/cdt/core/settings/model/CMacroEntry.java
@@ -10,6 +10,8 @@
  *******************************************************************************/
 package org.eclipse.cdt.core.settings.model;
 
+import org.eclipse.cdt.internal.core.SafeStringInterner;
+
 
 
 public final class CMacroEntry extends ACSettingEntry implements ICMacroEntry{
@@ -17,7 +19,7 @@ public final class CMacroEntry extends ACSettingEntry implements ICMacroEntry{
 
 	public CMacroEntry(String name, String value, int flags) {
 		super(name, flags);
-		fValue = value;
+		fValue = SafeStringInterner.safeIntern(value);
 		if(fValue == null)
 			fValue = "";	//$NON-NLS-1$
 	}