crashes if label has a table with sides="ltb"

[Ranieri Batista]

I get this error with dot, neato, and fdp, if I use a label containing a <table> (or <td>) with the SIDES attribute set to any permutation of "ltb" (to render all table or cell borders except the right one).

*** stack smashing detected ***: dot terminated

Tested on Ubuntu 16.04 x64
dot - graphviz version 2.38.0 (20140413.2041)

digraph bottom_left_top { n [label=<<table sides="lbt"><tr><td></td></tr></table>>] }

[John Ellson (ellson)]

FYI - I can't reproduce this bug with the latest nightly snapshots from graphviz.org.

I know, I know, we need to make a new stable release ....