I saw this error on Tiger PPC with apple-gcc-4.2 :info:build ./src/dfa/closure_posix.h:128: error: no match for 'operator!=' in 'c != std::vector<_Tp, _Alloc>::rend() [with _Tp = re2c::clos_t, _Alloc = std::allocator<re2c::clos_t>]()' Force-building it with gcc6 worked. Ken