diff --git a/xpcom/base/nsILeakDetector.idl b/xpcom/base/nsILeakDetector.idl
index 549be853c263..54aae636bc11 100644
--- a/xpcom/base/nsILeakDetector.idl
+++ b/xpcom/base/nsILeakDetector.idl
@@ -33,5 +33,5 @@ interface nsILeakDetector : nsISupports {
 	void traceObject(in nsISupports object, in PRBool verbose);
 	void traceCollection(in nsICollection objects, in PRBool verbose);
 	void markObject(in nsISupports object, in PRBool marked);
-	nsISupports getServices();
+	readonly attribute nsISupports services;
 };