Remove support for meta-object revisions < 7

For Qt5 we no longer want to support the older revisions due to the
dual codepaths that must be maintained, and because the format of the
meta-object data is quite different in revision 7.

The dual codepaths have been replaced by asserts that indicate the
revision in which the feature was introduced, and the older-revision
fallbacks have been removed.

It's not possible to build code generated by moc that has
revision <= 6 with Qt5 because the type of the
QMetaObject::stringdata member changed from const char * to const
QByteArrayData *. For the same reason it's not possible to build a
dynamic meta-object generator targeting revision <= 6 with Qt5.
Hence, too old meta-objects will be caught at compile time, and the
code will have to be ported to generate revision 7 (e.g., by running
Qt5's moc on the original class declaration).

Change-Id: I33f05878a2d3ee3de53fc7009f7a367f55c25e36
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@nokia.com>
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
Reviewed-by: João Abecasis <joao.abecasis@nokia.com>
Reviewed-by: Lars Knoll <lars.knoll@nokia.com>

1 files changed, 11 insertions, 16 deletions

diff --git a/src/corelib/kernel/qmetaobjectbuilder.cpp b/src/corelib/kernel/qmetaobjectbuilder.cpp
index e282a22f70..59740960c9 100644
--- a/src/corelib/kernel/qmetaobjectbuilder.cpp
+++ b/src/corelib/kernel/qmetaobjectbuilder.cpp
@@ -737,16 +737,12 @@ void QMetaObjectBuilder::addMetaObject
 
     if ((members & RelatedMetaObjects) != 0) {
         const QMetaObject **objects;
-        if (priv(prototype->d.data)->revision < 2) {
-            objects = (const QMetaObject **)(prototype->d.extradata);
-        } else
-        {
-            const QMetaObjectExtraData *extra = (const QMetaObjectExtraData *)(prototype->d.extradata);
-            if (extra)
-                objects = extra->objects;
-            else
-                objects = 0;
-        }
+        Q_ASSERT(priv(prototype->d.data)->revision >= 2);
+        const QMetaObjectExtraData *extra = (const QMetaObjectExtraData *)(prototype->d.extradata);
+        if (extra)
+            objects = extra->objects;
+        else
+            objects = 0;
         if (objects) {
             while (*objects != 0) {
                 addRelatedMetaObject(*objects);
@@ -756,12 +752,11 @@ void QMetaObjectBuilder::addMetaObject
     }
 
     if ((members & StaticMetacall) != 0) {
-        if (priv(prototype->d.data)->revision >= 6) {
-            const QMetaObjectExtraData *extra =
-                (const QMetaObjectExtraData *)(prototype->d.extradata);
-            if (extra && extra->static_metacall)
-                setStaticMetacallFunction(extra->static_metacall);
-        }
+        Q_ASSERT(priv(prototype->d.data)->revision >= 6);
+        const QMetaObjectExtraData *extra =
+            (const QMetaObjectExtraData *)(prototype->d.extradata);
+        if (extra && extra->static_metacall)
+            setStaticMetacallFunction(extra->static_metacall);
     }
 }