diff options
authorJan Arve Sæther <>2021-01-13 14:33:55 +0100
committerQt Cherry-pick Bot <>2021-01-13 21:42:08 +0000
commite15d63baa34a586084f826093d6fd76278f5946d (patch)
parent4b3417f0f41b6b62091c90ca35bbbed2b232c354 (diff)
a11y: Do not cache classes that don't have a factory plugin
For Qt Widgets we thought it was a good idea to also store in the cache if a class didn't have a factory plugin. This worked fine there, since the number of QWidget classnames is quite limited (so the factory plugin cache will soon reach a limit) In QML however, classes are often suffixed with e.g. Button_QMLTYPE_123, Button_QMLTYPE_124 etc. This number suffix is just increased continuously. This could lead to that the factory plugin cache will grow ad infinitum, which will cause "memory leaks" in addition to a performance penalty. Fixes: QTBUG-75106 Change-Id: I9ba189f989f0b90ab62a2c54a2e9230236a998d8 Reviewed-by: Volker Hilsheimer <> (cherry picked from commit 583668005d4d6399fc16d165dcb6a5af2b94323d) Reviewed-by: Qt Cherry-pick Bot <>
1 files changed, 4 insertions, 5 deletions
diff --git a/src/gui/accessible/qaccessible.cpp b/src/gui/accessible/qaccessible.cpp
index f2bc48fd0c..dc6794ac9c 100644
--- a/src/gui/accessible/qaccessible.cpp
+++ b/src/gui/accessible/qaccessible.cpp
@@ -695,15 +695,14 @@ QAccessibleInterface *QAccessible::queryAccessibleInterface(QObject *object)
// Find a QAccessiblePlugin (factory) for the class name. If there's
// no entry in the cache try to create it using the plugin loader.
if (!qAccessiblePlugins()->contains(cn)) {
- QAccessiblePlugin *factory = nullptr; // 0 means "no plugin found". This is cached as well.
const int index = loader()->indexOf(cn);
- if (index != -1)
- factory = qobject_cast<QAccessiblePlugin *>(loader()->instance(index));
- qAccessiblePlugins()->insert(cn, factory);
+ if (index != -1) {
+ QAccessiblePlugin *factory = qobject_cast<QAccessiblePlugin *>(loader()->instance(index));
+ qAccessiblePlugins()->insert(cn, factory);
+ }
// At this point the cache should contain a valid factory pointer or 0:
- Q_ASSERT(qAccessiblePlugins()->contains(cn));
QAccessiblePlugin *factory = qAccessiblePlugins()->value(cn);
if (factory) {
QAccessibleInterface *result = factory->create(cn, object);