From 68b855c215865a865672e2a43a70b2033e97a0f3 Mon Sep 17 00:00:00 2001
From: Ulf Hermann <ulf.hermann@qt.io>
Date: Mon, 7 Jun 2021 14:54:20 +0200
Subject: [PATCH] Universally pass QMetaType by value

... and add Qt7 TODOs where we can't because of BC.

Change-Id: Idce8b677ae95231e1690ac4265dc6f06818052e7
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
---
 src/corelib/kernel/qassociativeiterable.h             | 2 ++
 src/corelib/kernel/qiterable_p.h                      | 2 +-
 src/corelib/kernel/qsequentialiterable.h              | 2 ++
 src/corelib/kernel/qvariant.h                         | 1 +
 tests/auto/corelib/kernel/qproperty/tst_qproperty.cpp | 6 +++---
 5 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/corelib/kernel/qassociativeiterable.h b/src/corelib/kernel/qassociativeiterable.h
index b940f605b8..6fe0ff670c 100644
--- a/src/corelib/kernel/qassociativeiterable.h
+++ b/src/corelib/kernel/qassociativeiterable.h
@@ -122,12 +122,14 @@ public:
     {
     }
 
+    // ### Qt7: Pass QMetaType as value rather than const ref.
     QAssociativeIterable(const QMetaAssociation &metaAssociation, const QMetaType &metaType,
                          void *iterable)
         : QIterable(metaAssociation, metaType.alignOf(), iterable)
     {
     }
 
+    // ### Qt7: Pass QMetaType as value rather than const ref.
     QAssociativeIterable(const QMetaAssociation &metaAssociation, const QMetaType &metaType,
                          const void *iterable)
         : QIterable(metaAssociation, metaType.alignOf(), iterable)
diff --git a/src/corelib/kernel/qiterable_p.h b/src/corelib/kernel/qiterable_p.h
index 979ef49b18..d975a591fb 100644
--- a/src/corelib/kernel/qiterable_p.h
+++ b/src/corelib/kernel/qiterable_p.h
@@ -59,7 +59,7 @@ QT_BEGIN_NAMESPACE
 namespace QIterablePrivate {
 
 template<typename Callback>
-static QVariant retrieveElement(const QMetaType &type, Callback callback)
+static QVariant retrieveElement(QMetaType type, Callback callback)
 {
     QVariant v(type);
     void *dataPtr;
diff --git a/src/corelib/kernel/qsequentialiterable.h b/src/corelib/kernel/qsequentialiterable.h
index 8755b07aec..7b08e2afa3 100644
--- a/src/corelib/kernel/qsequentialiterable.h
+++ b/src/corelib/kernel/qsequentialiterable.h
@@ -115,12 +115,14 @@ public:
     {
     }
 
+    // ### Qt7: Pass QMetaType as value rather than const ref.
     QSequentialIterable(const QMetaSequence &metaSequence, const QMetaType &metaType,
                         void *iterable)
         : QIterable(metaSequence, metaType.alignOf(), iterable)
     {
     }
 
+    // ### Qt7: Pass QMetaType as value rather than const ref.
     QSequentialIterable(const QMetaSequence &metaSequence, const QMetaType &metaType,
                         const void *iterable)
         : QIterable(metaSequence, metaType.alignOf(), iterable)
diff --git a/src/corelib/kernel/qvariant.h b/src/corelib/kernel/qvariant.h
index 9ebdbc4a18..ae39946cc3 100644
--- a/src/corelib/kernel/qvariant.h
+++ b/src/corelib/kernel/qvariant.h
@@ -666,6 +666,7 @@ namespace QtPrivate {
 class Q_CORE_EXPORT QVariantTypeCoercer
 {
 public:
+    // ### Qt7: Pass QMetaType as value rather than const ref.
     const void *convert(const QVariant &value, const QMetaType &type);
     const void *coerce(const QVariant &value, const QMetaType &type);
 
diff --git a/tests/auto/corelib/kernel/qproperty/tst_qproperty.cpp b/tests/auto/corelib/kernel/qproperty/tst_qproperty.cpp
index 735d45da2a..60a4e3147d 100644
--- a/tests/auto/corelib/kernel/qproperty/tst_qproperty.cpp
+++ b/tests/auto/corelib/kernel/qproperty/tst_qproperty.cpp
@@ -738,7 +738,7 @@ void tst_QProperty::genericPropertyBinding()
 
     {
         QUntypedPropertyBinding doubleBinding(QMetaType::fromType<double>(),
-                                              [](const QMetaType &, void *) -> bool {
+                                              [](QMetaType , void *) -> bool {
             Q_ASSERT(false);
             return true;
         }, QPropertyBindingSourceLocation());
@@ -746,7 +746,7 @@ void tst_QProperty::genericPropertyBinding()
     }
 
     QUntypedPropertyBinding intBinding(QMetaType::fromType<int>(),
-                                    [](const QMetaType &metaType, void *dataPtr) -> bool {
+                                    [](QMetaType metaType, void *dataPtr) -> bool {
         Q_ASSERT(metaType.id() == qMetaTypeId<int>());
 
         int *intPtr = reinterpret_cast<int*>(dataPtr);
@@ -766,7 +766,7 @@ void tst_QProperty::genericPropertyBindingBool()
     QVERIFY(!property.value());
 
     QUntypedPropertyBinding boolBinding(QMetaType::fromType<bool>(),
-            [](const QMetaType &, void *dataPtr) -> bool {
+            [](QMetaType, void *dataPtr) -> bool {
         auto boolPtr = reinterpret_cast<bool *>(dataPtr);
         *boolPtr = true;
         return true;