Hi, In reaction to Akim's request, I've whipped together a Portfile for bison 3.0.4 with the legacy 2.7.1 in a subport. It builds for me on 10.9.5, but I haven't tested the resulting executable(s) yet. https://trac.macports.org/ticket/41600#comment:21 If the subport should be called bison2 rather than bison-2, I have no objections. R.