Rendering a corrupted image results in 0-byte output & 0 status return code
When attempting to render a digraph from a .dot which includes references to images -- if any image is incomplete/corrupted, dot creates a 0-byte output file (specified by -o) and returns a 0 code, implying that nothing went wrong.
dot -Tpng input.dot -o output.png
$ dot -V
dot - graphviz version 2.38.0 (20140413.2041)