<p dir="ltr">I'm having trouble when it doesn't fuse—it ends up with duplicate bindings at the top level, because build gets inlined n times, and the result lifted out. Nothing's *wrong* with the code, except that there are multiple copies of it.</p>
<div class="gmail_quote">On Aug 15, 2014 10:58 AM, "GHC" <<a href="mailto:ghc-devs@haskell.org">ghc-devs@haskell.org</a>> wrote:<br type="attribution"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
#9434: GHC.List.reverse does not fuse<br>
-------------------------------------+-------------------------------------<br>
Reporter: dfeuer | Owner:<br>
Type: bug | Status: new<br>
Priority: normal | Milestone:<br>
Component: | Version: 7.9<br>
libraries/base | Keywords:<br>
Resolution: | Architecture: Unknown/Multiple<br>
Operating System: | Difficulty: Easy (less than 1<br>
Unknown/Multiple | hour)<br>
Type of failure: Runtime | Blocked By:<br>
performance bug | Related Tickets:<br>
Test Case: |<br>
Blocking: |<br>
Differential Revisions: |<br>
-------------------------------------+-------------------------------------<br>
<br>
Comment (by simonpj):<br>
<br>
Great. Just check that when fusion ''doesn't'' take place, the result is<br>
good. And do a `nofib` comparison for good luck. Then submit a patch.<br>
<br>
Thanks for doing all this work on fusion, David.<br>
<br>
Simon<br>
<br>
--<br>
Ticket URL: <<a href="http://ghc.haskell.org/trac/ghc/ticket/9434#comment:2" target="_blank">http://ghc.haskell.org/trac/ghc/ticket/9434#comment:2</a>><br>
GHC <<a href="http://www.haskell.org/ghc/" target="_blank">http://www.haskell.org/ghc/</a>><br>
The Glasgow Haskell Compiler<br>
</blockquote></div>