Interesting result. I've just attached a much smaller test case to the
ticket - it would be good to see if that fails or passes with RC2, or
breaks at the same point.
The fact that there does seem to be a regression between RC2 and RC3
(either a regression itself, or making a previous bug easier to hit)
makes me think that a release might not be such a great idea.
Thanks, Neil
On Sat, Mar 21, 2015 at 11:35 AM, Herbert Valerio Riedel
On 2015-03-21 at 08:21:20 +0100, Herbert Valerio Riedel wrote:
On 2015-03-21 at 07:56:32 +0100, Neil Mitchell wrote:
[...]
3) I tested with GHC RC1 and GHC RC2, both of which were fine. The fact no one else hit this with RC2 might just be because its a very recent regression.
We -- and by that I don't mean myself... :) -- could git-bisect between RC2 and RC3 here (semi-)automatically (i.e. maybe unattended if it's scriptable) if your test-case (even if it's not minimal) reliably triggers the bug...
I scripted up a test and git-bisected between RC2 and RC3, and the following commit is the one where `shake-test oracle test` starts failing
http://git.haskell.org/ghc.git/commitdiff/6f46fe15af397d448438c6b93babcdd68d...
...which sadly is a rather large patch :-/