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

[Joe Zbiciak]

Paul,

Thank you for looking into this.  A useful error message is far
better than a crash--at least now I know what is incorrect about
my input.  I didn't know enough about bison internals to figure
out what I was doing wrong.  I don't use bison very often, and have
only limited gramamr-writing skills.

Thank you for looking into the bug report.  I'll modify my grammar
appropriately.

Regards,

--Joe


On Tue, May 25, 2004 at 03:32:12PM -0700, Paul Eggert address@hidden wrote:
| 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.

-- 
:  Joseph Zbiciak, MGTS   :  "If I set here and stare at nothing   :
:  address@hidden      :   long enough, people might think I'm  :
:  #include <std_disc.h>  :   an engineer working on something."   :
:  Texas Instruments      :                       -- S.R. McElroy  :