Occasionally trim the type cache

As loaded components are kept in a cache, they are never removed by the
garbage collector. So, if you periodically create new components, they
leak. This change adds a floating threshold for the number of
components. When that threshold is surpassed trimCache() is called and
unneeded components are removed.

Task-number: QTBUG-42055
Change-Id: I30e3e4ee287f6d34376713668009c67614a50e0c
Reviewed-by: Simon Hausmann <simon.hausmann@theqtcompany.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/qml/qml/qqmltypeloader_p.h b/src/qml/qml/qqmltypeloader_p.h
index 6433601ba8..f565bcd31f 100644
--- a/src/qml/qml/qqmltypeloader_p.h
+++ b/src/qml/qml/qqmltypeloader_p.h
@@ -358,6 +358,7 @@ private:
     QQmlTypeLoaderThread *m_thread;
     NetworkReplies m_networkReplies;
     TypeCache m_typeCache;
+    int m_typeCacheTrimThreshold;
     ScriptCache m_scriptCache;
     QmldirCache m_qmldirCache;
     ImportDirCache m_importDirCache;
@@ -365,6 +366,7 @@ private:
 
     template<typename Loader>
     void doLoad(const Loader &loader, QQmlDataBlob *blob, Mode mode);
+    void updateTypeCacheTrimThreshold();
 
     friend struct PlainLoader;
     friend struct CachedLoader;