Sorting a sparse array with Array.sort leads to nullpointer dereference

When sorting a sparse array (SparseArrayData) with Array.sort, the engine crashes due to a nullpointer dereference:

const v3 = [1,2,3];
v3[10000] = 0;
const v5 = v3.sort();

The root cause appears to be the call to thisObject->setArrayData(nullptr); in qv4arraydata.cpp:746. I am not quite sure why it is there (perhaps to reset the object's storage to set it up for the sorted elements?) - accessing the array data afterwards leads in order to sort the array leads to the crash.