Use a linked list instead of a QSet<> to track expressions

While the QSet<> wasn't that expensive, the QmlContext only tracks the
expressions to stop programmers doing something "stupid" so any overhead is
unacceptable.  This does give a measurable improvement.

1 files changed, 3 insertions, 1 deletions

diff --git a/src/declarative/qml/qmlcontext_p.h b/src/declarative/qml/qmlcontext_p.h
index 4240c8a..60655ae 100644
--- a/src/declarative/qml/qmlcontext_p.h
+++ b/src/declarative/qml/qmlcontext_p.h
@@ -67,6 +67,7 @@ class QmlContext;
 class QmlExpression;
 class QmlEngine;
 class QmlExpression;
+class QmlExpressionPrivate;
 
 class QmlContextPrivate : public QObjectPrivate
 {
@@ -102,7 +103,8 @@ public:
 
     void invalidateEngines();
     QSet<QmlContext *> childContexts;
-    QSet<QmlExpression *> childExpressions;
+
+    QmlExpressionPrivate *expressions;
 
     QmlSimpleDeclarativeData contextData;
     QObjectList contextObjects;