Zero-sized blocks

Submitted by Christoph Hertzberg @chhtz

Assigned to Christoph Hertzberg @chhtz

Link to original bugzilla bug (#696)
Version: 3.2

Description

Due to a runtime assert, it is currently not possible to extract fixed-sized blocks where one dimension is zero. (A use-case for that is to reduce trivial branches in user code).
The local fix is trivial, but for proper unit-tests some other parts require adaption as well.

Blocking

#558 (closed)