GHC 6.2.1 and FedoraCore2: ar-related build problem, looked like readline problem

[Sven Panne]

Henrik Nilsson wrote:
> Testing stderr seemed horribly fragile to me, though: who knows
> what people may or may not opt to write to stderr in various
> versions of "ar" now or in the future? That's why I thought
> looking for concrete evidence that the right thing actually
> had happened might be a more solid solution.

Nope, testing for stderr is not fragile: Any tool which writes to
stderr during normal execution is doing something horribly wrong.
Testing stderr for evidence when the tool is known to return wrong
exit codes is standard autoconf practice.

The problem with your approach is portability, e.g. "dd" is a bit
unusual in autoconf tests, and I'm not sure if the find option
"-size +10k" is really portable. The rules of the autoconf game
are: "Use incredibly simple shell commands to detect ridiculously
complex features." :-]

Cheers,
    S.