QFETCH() crashes with QVector2D, QVector3D and QVector4D in Release mode

For some reason that escapes me, if I write a data driven test that takes a QVector3D as input and run the test in Release mode, the QFETCH() macro crashes due to a segmentation fault while fetching the value from the _data() function.  (This also occurs with QVector2D and QVector4D).

However, if I run the test in Debug mode it works just fine.

Therefore I believe the cause behind the crash might be some unwanted side effects of the optimization done by the compiler in Release mode.

The following minimal example works fine in Debug mode but crashes in Release mode:

main.cpp

#include <QVector3D>
#include <QtTest>

class MyTest : public QObject
{
    Q_OBJECT

private slots:

    void myTest_data();
    void myTest();
};

void MyTest::myTest_data()
{
    QTest::addColumn<QVector3D>("vec");
    QTest::newRow("foo") << QVector3D(1, 2, 3);
}

void MyTest::myTest()
{
    QFETCH(QVector3D, vec);

    QCOMPARE(vec.x(), 1);
    QCOMPARE(vec.y(), 2);
    QCOMPARE(vec.z(), 3);
}

QTEST_APPLESS_MAIN(MyTest);
#include "main.moc"

This is the fatal error message shown in the console:

(gdb) QFATAL : MyTest::myTest(foo) Received signal 11
         Function time: 0ms Total time: 0ms
FAIL!  : MyTest::myTest(foo) Received a fatal error.
   Loc: [Unknown file(0)]
Totals: 1 passed, 1 failed, 0 skipped, 0 blacklisted, 48ms
********* Finished testing of MyTest *********
=== End of stack trace ===