What the heck does this backtrace mean?

[Aidan Kehoe]

 Ar an cúigiú lá is fiche de mí Feabhra, scríobh David Kastrup: 

 > I'd prefer
 > M-x check-parens RET
 > 
 > It is less complicated and does not pollute the mark stack.

Something we should merge from GNU, then. 

-- 
On the quay of the little Black Sea port, where the rescued pair came once
more into contact with civilization, Dobrinton was bitten by a dog which was
assumed to be mad, though it may only have been indiscriminating. (Saki)