Document issue with heapam line pointer truncation.
commitc7aeb775df895db240dcd6f47242f7e08899adfb
authorPeter Geoghegan <pg@bowt.ie>
Thu, 23 Sep 2021 02:21:36 +0000 (22 19:21 -0700)
committerPeter Geoghegan <pg@bowt.ie>
Thu, 23 Sep 2021 02:21:36 +0000 (22 19:21 -0700)
treef2e2e1c50c46d176623570d168d00dda18049278
parent85c69611288f4096b7460d980bedaa777f824d24
Document issue with heapam line pointer truncation.

Checking that an offset number isn't past the end of a heap page's line
pointer array was just a defensive sanity check for HOT-chain traversal
code before commit 3c3b8a4b.  It's etrictly necessary now, though.  Add
comments that reference the issue to code in heapam that needs to get it
right.

Per suggestion from Alexander Lakhin.

Discussion: https://postgr.es/m/f76a292c-9170-1aef-91a0-59d9443b99a3@gmail.com
src/backend/access/heap/heapam.c
src/backend/access/heap/pruneheap.c