There is autogen.sh in source tree. It can be replaced with "autoreconf -i" or simply removed. According to ChangeLog of autoconf, autoreconf has been there for at least 10 years. I also looked at configure.ac. In attached patch I added dillo URL, used AS_HELP_STRING to format help lines, replaced AC_ERROR with AC_MSG_ERROR (it was renamed) and replaced -D flags with AC_DEFINE. If no config.h is used, flags should be added to DEFS variable, but with config.h they should be defined in config.h using AC_DEFINE. The problem is that not all files include config.h. I added #includes where necessary, but to avoid problems when some files see defines and some files don't, config.h should be included by every .c and .cc file before all other includes.