Re: Remove useless associativity/precedence from parsers

Andrew Dunstan <andrew(dot)dunstan(at)2ndquadrant(dot)com> writes:
> On 5/21/19 11:49 AM, Akim Demaille wrote:
>> Usually users of Bison build tarballs with the generated parsers
>> in them, and ship/test from that.

> The buildfarm client does not build from tarballs, it builds from git,
> meaning it has to run bison. Thus Tom's objection is quite valid, and
> your dismissal of it is not.

Right, but that's a much narrower set of people who need to update
than "all PG users" or even "all PG developers".

I checked the buildfarm's configure results not too long ago, and noted
that the oldest bison versions are

gaur | configure: using bison (GNU Bison) 1.875
prairiedog | configure: using bison (GNU Bison) 1.875
dromedary | configure: using bison (GNU Bison) 2.3
locust | configure: using bison (GNU Bison) 2.3
longfin | configure: using bison (GNU Bison) 2.3
nudibranch | configure: using bison (GNU Bison) 2.3
anole | configure: using bison (GNU Bison) 2.4.1
fulmar | configure: using bison (GNU Bison) 2.4.1
gharial | configure: using bison (GNU Bison) 2.4.1
grouse | configure: using bison (GNU Bison) 2.4.1
koreaceratops | configure: using bison (GNU Bison) 2.4.1
leech | configure: using bison (GNU Bison) 2.4.1
magpie | configure: using bison (GNU Bison) 2.4.1
treepie | configure: using bison (GNU Bison) 2.4.1
coypu | configure: using bison (GNU Bison) 2.4.3
friarbird | configure: using bison (GNU Bison) 2.4.3
nightjar | configure: using bison (GNU Bison) 2.4.3
(then 2.5 and later)

(This doesn't cover the Windows members, unfortunately.)

gaur and prairiedog are my own pet dinosaurs, and updating them would
not be very painful. (Neither of them are using the original vendor
Bison to begin with ... as I said, they're dinosaurs.) Meanwhile,
three of the 2.3 members are Mac systems; nudibranch is SUSE 11.
Requiring anything newer than 2.4.1 would start to cause problems
for a fair number of people, I think.

Still, the bottom line here is that we could require a new(ish) Bison
if we could point to clear benefits that outweigh the pain. Right
now there's not much argument for it.

regards, tom lane