Bug with upvalue multi-assignment (corner case - Lua 5.x)

[alex.mania@...]

Here's a demonstration: http://pastebin.com/zNtdfRrf

I'm wondering:

is the above undocumented but intended behaviour? (it'd be pretty nasty to document)
or is the ordering implementation-defined, ie would LuaJIT be allowed to handle it differently?
or is the above a bug that will/should be corrected?

Regards,
- Alex Davies

(Apologies if this is html, sent via webmail)