QImageReader.size() crashes or aborts with SVG

I want to check the recommended aspect ratio of a SVG file in a time-critical situation, so I write the following example program:

#include <QImageReader>
#include <QDebug>

int main(int argc, char **argv)
{
    QImageReader reader("Suojatie.svg");

    qDebug() << reader.size();
}

I expect it to return any QSize with a reasonable aspect ratio. However, it crashes (Ubuntu) or aborts (Scratchbox). The abort message is:

ASSERT: "!m_nodes.isEmpty()" in file qsvghandler.cpp, line 3644
Aborted (core dumped)

I have attached two SVG's (from Wikipedia) which both cause this behavior.