Fix QtQuick2 module unload support

This commit ensures that the value type providers installed by the
QtQuick2 QML module during initialization are uninstalled when the
plugin is unloaded.

It also fixes a bug in the type compiler so that it now works with
types from plugins which get unloaded and then reloaded.

Task-number: QTBUG-43004
Change-Id: I4b3fb75aae65dfbc5de9c88701ed82514087ab7d
Reviewed-by: Matthew Vogt <matthew.vogt@qinetic.com.au>

6 files changed, 20 insertions, 1 deletions

diff --git a/src/imports/qtquick2/plugin.cpp b/src/imports/qtquick2/plugin.cpp
index d5096fc6e8..ad3db2290f 100644
--- a/src/imports/qtquick2/plugin.cpp
+++ b/src/imports/qtquick2/plugin.cpp
@@ -49,6 +49,11 @@ public:
         Q_UNUSED(uri);
         QQmlQtQuick2Module::defineModule();
     }
+
+    ~QtQuick2Plugin()
+    {
+        QQmlQtQuick2Module::undefineModule();
+    }
 };
 //![class decl]
 
diff --git a/src/qml/compiler/qqmltypecompiler.cpp b/src/qml/compiler/qqmltypecompiler.cpp
index 3a27a859fd..8edf4bbe7c 100644
--- a/src/qml/compiler/qqmltypecompiler.cpp
+++ b/src/qml/compiler/qqmltypecompiler.cpp
@@ -1389,7 +1389,7 @@ void QQmlComponentAndAliasResolver::findAndRegisterImplicitComponents(const QmlI
         if (!mo)
             continue;
 
-        static QQmlType *componentType = QQmlMetaType::qmlType(&QQmlComponent::staticMetaObject);
+        QQmlType *componentType = QQmlMetaType::qmlType(&QQmlComponent::staticMetaObject);
         Q_ASSERT(componentType);
 
         QmlIR::Object *syntheticComponent = pool->New<QmlIR::Object>();
diff --git a/src/quick/qtquick2.cpp b/src/quick/qtquick2.cpp
index 6acff85961..09784d161a 100644
--- a/src/quick/qtquick2.cpp
+++ b/src/quick/qtquick2.cpp
@@ -194,5 +194,10 @@ void QQmlQtQuick2Module::defineModule()
     }
 }
 
+void QQmlQtQuick2Module::undefineModule()
+{
+    QQuick_deinitializeProviders();
+}
+
 QT_END_NAMESPACE
 
diff --git a/src/quick/qtquick2_p.h b/src/quick/qtquick2_p.h
index 2847d5d3ff..8f415cbd02 100644
--- a/src/quick/qtquick2_p.h
+++ b/src/quick/qtquick2_p.h
@@ -42,6 +42,7 @@ class Q_QUICK_PRIVATE_EXPORT QQmlQtQuick2Module
 {
 public:
     static void defineModule();
+    static void undefineModule();
 };
 
 QT_END_NAMESPACE
diff --git a/src/quick/qtquickglobal_p.h b/src/quick/qtquickglobal_p.h
index e2bf198b1c..7fe09da92e 100644
--- a/src/quick/qtquickglobal_p.h
+++ b/src/quick/qtquickglobal_p.h
@@ -54,6 +54,7 @@
 QT_BEGIN_NAMESPACE
 
 void QQuick_initializeProviders();
+void QQuick_deinitializeProviders();
 
 Q_DECLARE_LOGGING_CATEGORY(DBG_TOUCH)
 Q_DECLARE_LOGGING_CATEGORY(DBG_MOUSE)
diff --git a/src/quick/util/qquickglobal.cpp b/src/quick/util/qquickglobal.cpp
index 455e180dbe..139bae4038 100644
--- a/src/quick/util/qquickglobal.cpp
+++ b/src/quick/util/qquickglobal.cpp
@@ -982,4 +982,11 @@ void QQuick_initializeProviders()
     QQml_setGuiProvider(getGuiProvider());
 }
 
+void QQuick_deinitializeProviders()
+{
+    QQml_removeValueTypeProvider(getValueTypeProvider());
+    QQml_setColorProvider(0); // technically, another plugin may have overridden our providers
+    QQml_setGuiProvider(0);   // but we cannot handle that case in a sane way.
+}
+
 QT_END_NAMESPACE