Re: Bison 1.875 aborts (nsyms != ntokens + nvars) on attached input file

[Paul Eggert]

On 2004-04-23 in
<http://mail.gnu.org/archive/html/bug-bison/2004-04/msg00028.html>,
Joe Zbiciak <address@hidden> writes:

> Bison 1.875 under Solaris 2.8 aborts on the attached input file.
> Bison 1.25 and 1.35 seem to handle the file

Thanks for your bug report.  I think the problem is that the attached
file uses null characters in Bison tokens.  Unfortunately Bison does
not support this: older versions pretended to, but they failed in some
important cases.

This has been worked around in the latest Bison test version
<ftp://alpha.gnu.org/gnu/bison/bison-1.875d.tar.gz> by having Bison
reject null characters.  Thus, for your sample input, Bison will
report

input.y:40.26-27: invalid null character: `\\0'
input.y:42.40-41: invalid null character: `\\0'

This is not a happy situation, but (if it's any consolation) grammars
that use null characters are not portable: POSIX does not allow them.