[commit: ghc] ghc-8.0: Do not claim that -O2 does not do better than -O (d332df3)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : ghc-8.0
Link       : http://ghc.haskell.org/trac/ghc/changeset/d332df3fd95f2116c138073ccc5d85f8efe5f402/ghc

>---------------------------------------------------------------

commit d332df3fd95f2116c138073ccc5d85f8efe5f402
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Wed Mar 30 16:09:36 2016 +0200

    Do not claim that -O2 does not do better than -O
    
    when in fact it does. This was pointed out by Johannes Bechberger and
    supported with seemingly statistically sound evidence in his Bachelor
    thesis: Of the benchmark shootout programs, 80% benefit significantly by
    switchtng from -O to -O2.
    
    See https://uqudy.serpens.uberspace.de/blog/2016/02/08/ghc-performance-over-time/
    for a few raw numbers.
    
    Differential Revision: https://phabricator.haskell.org/D2065
    
    (cherry picked from commit 3d245bf5255ebfb72813596fa93b9051f7518321)


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d332df3fd95f2116c138073ccc5d85f8efe5f402
 docs/users_guide/using-optimisation.rst | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/docs/users_guide/using-optimisation.rst b/docs/users_guide/using-optimisation.rst
index bc8e700..5e4995d 100644
--- a/docs/users_guide/using-optimisation.rst
+++ b/docs/users_guide/using-optimisation.rst
@@ -79,9 +79,6 @@ one reason to stick to no-optimisation when developing code.
     runtime or space *worse* if you're unlucky. They are normally turned
     on or off individually.
 
-    At the moment, ``-O2`` is *unlikely* to produce better code than
-    ``-O``.
-
 .. ghc-flag:: -Odph
 
     .. index::