``-D --emit-dot`` Instead of normal output generate lexer graph in .dot format. The output can be converted to an image with the help of Graphviz (e.g. something like ``dot -Tpng -odfa.png dfa.dot``). ``-d --debug-output`` Emit ``YYDEBUG`` in the generated code. ``YYDEBUG`` should be defined by the user in the form of a void function with two parameters: ``state`` (lexer state or -1) and ``symbol`` (current input symbol of type ``YYCTYPE``). ``--dump-adfa`` Debug option: output DFA after tunneling (in .dot format). ``--dump-cfg`` Debug option: output control flow graph of tag variables (in .dot format). ``--dump-closure-stats`` Debug option: output statistics on the number of states in closure. ``--dump-dfa-det`` Debug option: output DFA immediately after determinization (in .dot format). ``--dump-dfa-min`` Debug option: output DFA after minimization (in .dot format). ``--dump-dfa-tagopt`` Debug option: output DFA after tag optimizations (in .dot format). ``--dump-dfa-tree`` Debug option: output DFA under construction with states represented as tag history trees (in .dot format). ``--dump-dfa-raw`` Debug option: output DFA under construction with expanded state-sets (in .dot format). ``--dump-interf`` Debug option: output interference table produced by liveness analysis of tag variables. ``--dump-nfa`` Debug option: output NFA (in .dot format).