https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92008
--- Comment #18 from Akim Demaille <akim.demaille at gmail dot com> --- WRT to "pure-parser", there seems to be some misunderstanding. News of 3.4 says: The %pure-parser directive is deprecated in favor of '%define api.pure' since Bison 2.3b (2008-05-27), but no warning was issued; there is one now. Note that since Bison 2.7 you are strongly encouraged to use '%define api.pure full' instead of '%define api.pure'. It does not say "%pure-parser is no longer supported"!
