Re: [BUG] failed assertion in EnsurePortalSnapshotExists()

"Drouvot, Bertrand"  writes:
> On 9/30/21 7:16 PM, Tom Lane wrote:
>> PS: Memo to self: in the back branches, the new field has to be
>> added at the end of struct Portal.

> out of curiosity, why?

Sticking it into the middle would create an ABI break for any
extension code that's looking at struct Portal, due to movement
of existing field offsets.  In HEAD that's fine, so we should
put the field where it makes the most sense.  But we have to
be careful about changing globally-visible structs in released
branches.

			regards, tom lane