I wrote:
> On 11/19/18, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
> [ abortive states ]
>> I think it might come from any other place between when you set it and
>> before it got cleared (like any intermediate buffer and pin related
>> API's).
>
> Okay, I will look into that.
LockBuffer(), visibilitymap_pin(), and GetVisibilityMapPins() don't
call errors at this level. I don't immediately see any additional good
places from which to clear the local map.
-John Naylor