An ArrayIndexOutOfBounds exception may occur when adding an attribute node to the TinyTree.
The problem occurs when the tree contains typed (that is, schema-validated) attribute nodes, and when the same physical TinyTree container is used to hold more than one actual tree; it will therefore only happen when schema-validated temporary trees are created. The problem arises because the code for expanding the arrays used to hold information about attributes assumes that the array attTypedValue is the same length as the arrays holding other information; but its length is actually equal to the number of attributes on the tree at the time it was created, which may be less than the current number of attributes if new trees have been added to the same container.
A patch is being raised to TinyTree.java in the 9.2 branch. A limited-release build 18.104.22.168 (EEN and EEJ only) will be created for use by anyone encountering this problem: please enquire to Saxonica if it is needed.