Fix dangling references

These were found with the help of -Wdangling-reference, which is
new in GCC 13.

The one in qtpaths.cpp is a false positive: parseLocationOrError()
returns a reference, so there's nothing for the full expression to
destroy. Moreover, it returns a reference to a static object, so
there's no destruction inside the function either.

The other two aren't, but are also harmless. QDBusMessage::arguments()
and QVariant::toList() return a stored QVariantList by value, so
QList's COW mechanism means at() returns a reference that will not be
destroyed. However, the compiler has no way of knowing that. And
since it depends on the implementation details, change the code to
not depend on that.


Change-Id: If53aa16fcc24586d752ffc76c193c81e43dc9d95
Reviewed-by: Thiago Macieira <[email protected]>
(cherry picked from commit 18def77d27f88ce26b6af29fe56a80429fed555d)
Reviewed-by: Qt Cherry-pick Bot <[email protected]>

3 files changed, 9 insertions, 2 deletions

diff --git a/src/dbus/qdbusintegrator.cpp b/src/dbus/qdbusintegrator.cpp
index db746d16dab..78b87c25c17 100644
--- a/src/dbus/qdbusintegrator.cpp
+++ b/src/dbus/qdbusintegrator.cpp
@@ -913,7 +913,8 @@ void QDBusConnectionPrivate::deliverCall(QObject *object, int /*flags*/, const Q
         if (id == QDBusMetaTypeId::message())
             break;
 
-        const QVariant &arg = msg.arguments().at(i - 1);
+        const QList<QVariant> args = msg.arguments();
+        const QVariant &arg = args.at(i - 1);
         if (arg.metaType() == id)
             // no conversion needed
             params.append(const_cast<void *>(arg.constData()));
diff --git a/src/gui/text/qcssparser.cpp b/src/gui/text/qcssparser.cpp
index 2f3c04dc54e..f79369a36b0 100644
--- a/src/gui/text/qcssparser.cpp
+++ b/src/gui/text/qcssparser.cpp
@@ -1439,7 +1439,8 @@ QColor Declaration::colorValue(const QPalette &pal) const
             return pal.color((QPalette::ColorRole)(d->parsed.toInt()));
         case qMetaTypeId<QList<QVariant>>():
             if (d->parsed.toList().size() == 1) {
-                const auto &value = d->parsed.toList().at(0);
+                auto parsedList = d->parsed.toList();
+                const auto &value = parsedList.at(0);
                 return qvariant_cast<QColor>(value);
             }
             break;
diff --git a/src/tools/qtpaths/qtpaths.cpp b/src/tools/qtpaths/qtpaths.cpp
index b4e2d749aa3..fa29381d789 100644
--- a/src/tools/qtpaths/qtpaths.cpp
+++ b/src/tools/qtpaths/qtpaths.cpp
@@ -252,6 +252,10 @@ int main(int argc, char **argv)
         results << typesList.join('\n');
     }
 
+    QT_WARNING_PUSH
+#if defined(Q_CC_GNU_ONLY) && Q_CC_GNU >= 1300 && Q_CC_GNU < 1400
+    QT_WARNING_DISABLE_GCC("-Wdangling-reference")
+#endif
     if (parser.isSet(display)) {
         const StringEnum &location = parseLocationOrError(parser.value(display));
         QString text = QStandardPaths::displayName(location.enumvalue);
@@ -303,6 +307,7 @@ int main(int argc, char **argv)
         QStringList paths = QStandardPaths::locateAll(location.enumvalue, searchitem, QStandardPaths::LocateFile);
         results << location.mapName(paths.join(pathsep));
     }
+    QT_WARNING_POP
 
 #if !QT_CONFIG(settings)
     if (parser.isSet(query) || parser.isSet(qtconf) || parser.isSet(queryformat)) {