[commit: ghc] master: Turn on -O2 for the RTS by default (3a6b1bf)

Repository : ssh://darcs.haskell.org//srv/darcs/ghc

On branch  : master

http://hackage.haskell.org/trac/ghc/changeset/3a6b1bfb08602a8193b0025f0fe47ec8ddf8dad2

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

commit 3a6b1bfb08602a8193b0025f0fe47ec8ddf8dad2
Author: Simon Marlow <[email protected]>
Date:   Fri Oct 26 11:12:49 2012 +0100

    Turn on -O2 for the RTS by default
    
    Optimisation now makes a difference when compiling .cmm code, because
    it enables the optimisation passes in CmmPipeline.  Recently validate
    has not been optimising the .cmm code because it uses SRC_HC_OPTS=-O0,
    which explains why I couldn't reproduce #7366 in validate (the bug
    miscompiled rts/PrimOps.cmm).

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

 mk/config.mk.in |    8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/mk/config.mk.in b/mk/config.mk.in
index a906d25..f8d4d6a 100644
--- a/mk/config.mk.in
+++ b/mk/config.mk.in
@@ -360,9 +360,11 @@ LAX_DEPENDENCIES = NO
 # ----------------------------------------------------------------------------
 # Options for GHC's RTS
 
-# For an optimised RTS (you probably don't want to change these; we build
-# a debugging RTS by default now.  Use -debug to get it).
-GhcRtsHcOpts=-optc-O2
+# Build an optimised RTS.  Remember that we need to turn on
+# optimisation both for C code (-optc-O2) and .cmm code (-O2).  For
+# the debugging RTS flavour, rts/ghc.mk overrides these to turn off
+# optimisation.
+GhcRtsHcOpts=-optc-O2 -O2
 GhcRtsCcOpts=-fomit-frame-pointer
 
 # Include the front panel code?  Needs GTK+.