BUG #15653: pg_detoast_datum_packed problem

The following bug has been logged on the website:

Bug reference:      15653
Logged by:          Vladimir Kokovic
Email address:      vladimir.kokovic@gmail.com
PostgreSQL version: Unsupported/Unknown
Operating system:   linux manjaro
Description:

This bug I have to report only for sentimental reasons because vkBytea
system exists since the version of PostgreSQL 7.4!
vkBytea system serves to restore all elemental PostgreSQL types in bytea
form.
It survived all versions in the meantime so that current GIT HEAD would
report SIGSEGV to the pg_bvarchar method.
My impression is that the problem is in the method pg_detoast_datum_packed
but i do not understand the reason why.  select * return all rows OK.

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