QMetaType of non-const ref: play nice with template instantiations

...by making QMetaTypeId2 contain all expected members. While we don't allow QMetaType from non-const references, we want to get to the static_assert telling us as much, instead of running into more or less incomprehensible error messages in the depths of qmetatype.h. Task-number: QTBUG-106672 Change-Id: Ica9b13fee95eda97cafab2cccdc5249dfc3dcdf2 Reviewed-by: Ulf Hermann <[email protected]> (cherry picked from commit 9b3de58) Reviewed-by: Qt Cherry-pick Bot <[email protected]>
StrataSource · Sep 22, 2022 · 617e1fe · 617e1fe
1 parent b404ad5
commit 617e1fe
Showing 1 changed file with 6 additions and 1 deletion.
diff --git a/src/corelib/kernel/qmetatype.h b/src/corelib/kernel/qmetatype.h
@@ -1127,7 +1127,12 @@ template <typename T>
 struct QMetaTypeId2<const T&> : QMetaTypeId2<T> {};
 
 template <typename T>
-struct QMetaTypeId2<T&> { enum {Defined = false }; };
+struct QMetaTypeId2<T&>
+{
+    using NameAsArrayType = void;
+    enum { Defined = false, IsBuiltIn = false };
+    static inline constexpr int qt_metatype_id() { return 0; }
+};
 
 namespace QtPrivate {
     template <typename T, bool Defined = QMetaTypeId2<T>::Defined>