Invalid declaration of ProString as a Q_MOVABLE_TYPE?

I am getting this compiler warning while compiling Qt Creator

.../src/corelib/tools/qvector.h: In instantiation of ‘QVector<T>::iterator QVector<T>::erase(QVector<T>::iterator, QVector<T>::iterator) [with T = ProString; QVector<T>::iterator = ProString*]’:
.../src/corelib/tools/qvector.h:448:3:   required from ‘void QVector<T>::remove(int) [with T = ProString]’
.../sailfish-qtcreator/src/shared/proparser/proitems.h:244:40:   required from here
.../src/corelib/tools/qvector.h:757:20: warning: ‘void* memmove(void*, const void*, size_t)’ writing to an object of type ‘class ProString’ with no trivial copy-assignment; use copy-assignment or copy-initialization instead [-Werror=class-memaccess]
             memmove(abegin, aend, (d->size - itemsToErase - itemsUntouched) * sizeof(T));
             ~~~~~~_^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The ProString class is declared as a Q_MOVABLE_TYPE and this does not seem to be correct.