#include <QtCore/QDebug>
#include <QtCore/QAssociativeIterable>
#include <QtCore/QVariant>
#include <QtCore/QMap>

int main(int, char**)
{
    auto container = QMap<int, int>();

    // Add a key with value `0`. Other values do not cause the bug
    container[0] = 1;

    auto containerVariant = QVariant::fromValue(container);
    auto iter = containerVariant.value<QAssociativeIterable>();
    auto f = iter.constFind(QStringLiteral("anything"));
    qDebug() << "Itercm" << (f != iter.constEnd());

  return 0;
}
 

Itercm true

Itercm false