crashes (same happens with graphviz 2.27.20100201.0545)
Similar files work ok. Neato can process the file.
Input file: b1909.dot
[erg] It's a fairly large graph for dot. Here is the trace log.
[erg] The stack is being blown in the recursive use of
treesearch() in ns.c. The graph in that phase has
752011 nodes and 1128201 edges.