Em sex., 9 de out. de 2020 às 17:47, Tom Lane <tgl@sss.pgh.pa.us> escreveu:
Ranier Vilela <ranier.vf@gmail.com> writes: > The trap is not on the second part of expression. Is in the first. > If the pointer is NULL, ExecCopySlot will be called.
Your initial comment indicated that you were worried about IncrementalSortState's group_pivot slot, but that is never going to be null in any execution function of nodeIncrementalSort.c, because ExecInitIncrementalSort always creates it.
(The test whether it's NULL in ExecReScanIncrementalSort therefore seems rather useless and misleading, but it's not actually a bug.)
The places that use TupIsNull are just doing so because that's the standard way to check whether a slot is empty. The null test inside the macro is pointless in this context (and in a lot of its other use-cases, too) but we don't worry about that.
So I said that TupIsNull was not the most appropriate.
