Just a quick note: ocamldoc in 3.12 dumps its help to
stderr, unlike every other tool in the distribution. The automatic argument detection of Findlib 1.2.6 fails to catch the output and so does not recognize any command line option. The quick fix is to edit and/or patch tools/extract_args/extract_args.ml, line 32 to read:
Sys.command (sprintf "%s -help >%s 2>&1"
before running ./configure