Re: VARATT_EXTERNAL_GET_POINTER is not quite there yet

Tom Lane wrote:
> Gregory Stark <stark(at)enterprisedb(dot)com> writes:
> > "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us> writes:
> >> It might work to change struct varlena's contents to something like
> >>
> >> char vl_len_[4]; /* Do not touch this field directly! */
> >> char vl_dat[1];
>
> > Oh, that would probably fix this problem pretty well.
>
> > Touching vl_dat is only safe if you've either just allocated the object
> > yourself or you've already detoasted it.
>
> Sure, but that's been true ever since TOAST was first put in. The
> varvarlena patch didn't change that coding rule.
>
> I'll go try the char[4] hack and see if it works on the machines I have.

Tom has applied this change to CVS HEAD and 8.3.X.

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://postgres.enterprisedb.com

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