Picksplit() seems to be an exceptional case here: the first and last
numbers in entryvec are invalid so
entryvec->vector[entryvec->n - 1]
is invalid. All the other GiST code Picksplit() functions use the
same convention. For example, see the btree_gist picksplit function, at
http://doxygen.postgresql.org/btree__utils__num_8c-source.html#l00241
OffsetNumber i, maxoff = entryvec->n - 1;
On Nov 23, 2010, at 10:22 AM, Alvaro Herrera wrote:
> Excerpts from Peter Tanski's message of mar nov 23 12:00:52 -0300
> 2010:
>
>> There are checks inside the Picksplit() function for the number of
>> entries:
>>
>> OffsetNumber maxoff = entryvec->n - 1;
>> int n_entries, j;
>> n_entries = Max(maxoff, 1) - 1;
>>
>> j = 0;
>> for (i = FirstOffsetNumber; i < maxoff; i = OffsetNumberNext(i)) {
>> FPrint* v = deserialize_fprint(entv[i].key);
>
> Isn't this off by one? Offset numbers are 1-based, so the maxoff
> computation is wrong.
>
> --
> Álvaro Herrera <alvherre@commandprompt.com>
> The PostgreSQL Company - Command Prompt, Inc.
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