Configure is not very explicit about bison requirements (from gforge #21703)
Imported issue: Initially reported by @chevilla in https://gforge.inria.fr/tracker/?group_id=1015&aid=21703
bison is necessary only when compiling sources from the git repository, so I agree that configure should be rather discreet about a bad or missing bison installation, but on the other hand, when compiling from the git repository, it would be good to have a clear warning from configure, before actually trying to compile. Maybe, we could use AC_MSG_WARN?
Also, notice that AC_PROG_YACC does not stop or warn when it fails to find a bison compatible program: its purpose is only to set the environment variable YACC to the most suitable choice on the given machine.
Finally, if byacc is installed rather than bison, we get the following syntax error:
byacc: e - line 107 of ""/user/chevilla/home/sollya/miniparser.y"", syntax error
%defines
^
This is maybe expected, but, again, I think that it should be the role of configure to warn about this before the user actually tries to compile.