Re: Add "-Wimplicit-fallthrough" to default flags

On Wed, May 13, 2020 at 10:02 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> Andy Fan <zhihui(dot)fan1213(at)gmail(dot)com> writes:
> >> FWIW, I got a warning for jsonpath_gram.c.
>
> Ugh. Confirmed here on Fedora 30 (bison 3.0.5).
>
> > I just found this just serval minutes ago. Upgrading your bison to the
> > latest version (3.6) is ok. I'd like we have a better way to share this
> > knowledge through. I spend ~30 minutes to troubleshooting this issue.
>
> I fear that is going to mean that we revert this patch.
> We are *NOT* moving the minimum bison requirement for this,
> especially not to a bleeding-edge bison version.

Yes, I didn't mean revert the patch, but I was thinking moving the minimum
bison. But since down to the warning level 3 also resolved the issue,
looks it is a better way to do it.

(On the other hand, if you have an old bison,
>
you likely also have an old gcc that doesn't know this warning
> switch, so maybe it'd be all right in practice?)
>
>
I just use an old bision and a newer gcc:( and I used "echo "COPT=-Wall
-Werror"
> src/Makefile.custom" which is same as our cfbot system. Thank you all
for so quick
fix!

Best Regards
Andy Fan