Discrepancy for QString::toInt(), QString::toDouble()'s locale behavior

From http://doc.qt.io/qt-5/qlocale.html#details:

QString::toInt(), QString::toDouble(), etc., interpret the string according to the default locale. If this fails, it falls back on the "C" locale.

From http://doc.qt.io/qt-5/qstring.html#toDouble:

The string conversion will always happen in the 'C' locale. For locale dependent conversion use QLocale::toDouble()