Repository : ssh://darcs.haskell.org//srv/darcs/ghc On branch : ghc-7.2
http://hackage.haskell.org/trac/ghc/changeset/6d534ea2cb909920c057a0418a2c7a527f8432b1 >--------------------------------------------------------------- commit 6d534ea2cb909920c057a0418a2c7a527f8432b1 Author: Simon Marlow <[email protected]> Date: Tue Jun 28 13:42:00 2011 +0100 doc tweak: mention that UNPACK doesn't work without -O >--------------------------------------------------------------- docs/users_guide/glasgow_exts.xml | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) diff --git a/docs/users_guide/glasgow_exts.xml b/docs/users_guide/glasgow_exts.xml index 16cc760..54b7a0f 100644 --- a/docs/users_guide/glasgow_exts.xml +++ b/docs/users_guide/glasgow_exts.xml @@ -8416,7 +8416,11 @@ data T = T {-# UNPACK #-} !Float compiler).</para> <para>Unpacking constructor fields should only be used in - conjunction with <option>-O</option>, in order to expose + conjunction with <option>-O</option><footnote>in fact, UNPACK + has no effect without <option>-O</option>, for technical + reasons + (see <ulink url="http://hackage.haskell.org/trac/ghc/ticket/5252";>tick + 5252</ulink>)</footnote>, in order to expose unfoldings to the compiler so the reboxing can be removed as often as possible. For example:</para> _______________________________________________ Cvs-ghc mailing list [email protected] http://www.haskell.org/mailman/listinfo/cvs-ghc
