Colm McHugh <colm(dot)mchugh(at)gmail(dot)com> writes:
> Attached is a patch for a write after allocated memory which we found in
> testing. Its an obscure case but can happen if the same column is used in
> different grouping keys, as in the example below, which uses tables from
> the regress test suite (build with --enable-cassert in order to turn on
> memory warnings). Patch is against master.
I confirm the appearance of the memory-overwrite warnings in HEAD.
It looks like the bad code is (mostly) the fault of commit b5635948.
Andrew, can you take a look at this fix?
regards, tom lane