The former messes in bad ways with the overload set (it, fatally, attracts char16_t, e.g.). The latter was probably added in response to ambiguities between (char) and (QChar). While it's harmless now, remove it, since it no longer pulls its weight. The no-ascii warning is now coming from QChar(char), so the protection isn't lost. [ChangeLog][QtCore][QString] The += operators taking char and QChar::SpecialCharacter have been removed as they cause adding a char16_t to QString to call the char overload, losing information. The append() function was not affected. Change-Id: I57116314bcc71c0d9476159513c0c10048239db3 Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io> Reviewed-by: Lars Knoll <lars.knoll@qt.io>