Re: [COMMITTERS] pgsql: Prevent "snapshot too old" from trying to return pruned TOAST tu

On Thu, Aug 4, 2016 at 10:58 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> On Thu, Aug 4, 2016 at 7:23 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> Robert Haas <rhaas(at)postgresql(dot)org> writes:
>>> Prevent "snapshot too old" from trying to return pruned TOAST tuples.
>>
>> Looks like this patch broke the build on castoroides. Recommend
>> changing InitToastSnapshot into a macro. (There's a reason why
>> InitDirtySnapshot is a macro.)
>
> What is the reason? We refuse to separate frontend and backend
> headers in any sort of principled way?

That was poorly phrased. I'll try again: I can't see any reason for
using a macro here except that it allows frontend code to compile this
without breaking. But that doesn't seem like a very good way of
solving that problem. There's surely no way for a casual reader of
the code to realize that macros can be used here and inline functions
cannot, especially because this works apparently works fine on most
machines, including mine.

Here's a patch. Is this what you want?

--
Robert Haas
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