[patch] Use "set -o pipefail"

[Stephen Lin]

On Thu, Jul 4, 2013 at 8:13 PM, Rafael Espíndola
<rafael.espindola at gmail.com> wrote:
>> Great, thanks!
>
> OK, I have committed all the support bits. The attached patch is all
> that is left to switch us to using pipefail. Any objections?
>
> Cheers,
> Rafael

Just my $0.02; I'm guessing this will break a lot of out-of-tree
tests, so maybe it would be wise to post a message to LLVMDev about it
and getting feedback there? Even if it's a good idea long-term, maybe
it would be convenient to hide this behind a switch that could be
easily controlled via a command line switch to help ease the
transition.

Stephen