Re: BUG #16045: vacuum_db crash and illegal memory alloc after pg_upgrade from PG11 to PG12

On Wed, Oct 09, 2019 at 10:07:01AM -0400, Tom Lane wrote:
>Tomas Vondra <tomas(dot)vondra(at)2ndquadrant(dot)com> writes:
>> FWIW I can reproduce this - it's enough to do this on the 11 cluster
>
>I failed to reproduce any problem from your example, but I was trying
>in C locale on a Linux machine. What environment are you testing?
>
> regards, tom lane

test=# show lc_collate ;
lc_collate
------------
C.UTF-8
(1 row)

I can reproduce this pretty easily like this:

1) build 11

git checkout REL_11_STABLE
./configure --prefix=/home/user/pg-11 --enable-debug --enable-cassert && make -s clean && make -s -j4 install

2) build 12

git checkout REL_12_STABLE
./configure --prefix=/home/user/pg-12 --enable-debug --enable-cassert && make -s clean && make -s -j4 install

3) create the 11 cluster

/home/user/pg-11/bin/pg_ctl -D /tmp/data-11 init
/home/user/pg-11/bin/pg_ctl -D /tmp/data-11 -l /tmp/pg-11.log start
/home/user/pg-11/bin/createdb test
/home/user/pg-11/bin/psql test

4) create the table

create table q_tbl_archiv as
with
qseason as (
select table_name,column_name, ordinal_position
,replace(column_name,'_season','') as col_qualifier
-- ,'id_'||replace(column_name,'_season','') as id_column
from information_schema.columns
order by table_name
)
select qs.*,c.column_name as id_column, c.column_default as id_default
from
qseason qs
left join information_schema.columns c on c.table_name=qs.table_name and
c.column_name like 'id_%';

5) shutdown the 11 cluster

/home/user/pg-11/bin/pg_ctl -D /tmp/data-11 stop

6) init 12 cluster

/home/user/pg-12/bin/pg_ctl -D /tmp/data-12 init

7) do the pg_upgrade thing

/home/user/pg-12/bin/pg_upgrade -b /home/user/pg-11/bin -B /home/user/pg-12/bin -d /tmp/data-11 -D /tmp/data-12 -k

8) start 12 cluster

/home/user/pg-12/bin/pg_ctl -D /tmp/data-12 -l /tmp/pg-12.log start

9) kabooom

/home/user/pg-12/bin/psql test -c "analyze q_tbl_archiv"

On my system (Fedora 30 in x86_64) this reliably results a crash (and
various other crashes as demonstrated in my previous message).

regards

--
Tomas Vondra http://www.2ndQuadrant.com
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