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Yes, but it is not feasible before GHC 8.6, due to needing GHC >= 8.2 for bootstrapping.<o:p></o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">True. But 8.4 will fork off shortly; so once that is done, we are happy with perf, we can add the change to master in preparation for 8.6.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Simon<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US">From:</span></b><span lang="EN-US"> ghc-devs [mailto:ghc-devs-bounces@haskell.org]
<b>On Behalf Of </b>Alan & Kim Zimmerman<br>
<b>Sent:</b> 22 November 2017 13:30<br>
<b>To:</b> ghc-devs@haskell.org<br>
<b>Subject:</b> Re: [GHC] #14490: TTG Snags<o:p></o:p></span></p>
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Yes, but it is not feasible before GHC 8.6, due to needing GHC >= 8.2 for bootstrapping.<o:p></o:p></p>
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<o:p> </o:p></p>
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<o:p> </o:p></p>
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On 22 November 2017 at 15:26, GHC <<a href="mailto:ghc-devs@haskell.org" target="_blank">ghc-devs@haskell.org</a>> wrote:<o:p></o:p></p>
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#14490: TTG Snags<br>
-------------------------------------+-------------------------------------<br>
Reporter: alanz | Owner: (none)<br>
Type: bug | Status: new<br>
Priority: normal | Milestone:<br>
Component: Compiler | Version: 8.3<br>
Resolution: | Keywords:<br>
Operating System: Unknown/Multiple | Architecture:<br>
| Unknown/Multiple<br>
Type of failure: None/Unknown | Test Case:<br>
Blocked By: | Blocking:<br>
Related Tickets: #14482 | Differential Rev(s):<br>
Wiki Page: |<br>
ImplementingTreesThatGrow |<br>
-------------------------------------+-------------------------------------<br>
<br>
Comment (by Shayan-Najd):<br>
<br>
> So making a Data instance per concrete version may be the best way to<br>
go. Plan B.<br>
<br>
Regardless of the GHC version we use, the question is whether Plan B<br>
really fixes the build-time problem. Can we test it?<br>
<span style="color:#888888"><br>
<span class="hoenzb">--</span><br>
<span class="hoenzb">Ticket URL: <<a href="https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fghc.haskell.org%2Ftrac%2Fghc%2Fticket%2F14490%23comment%3A31&data=02%7C01%7Csimonpj%40microsoft.com%7C3556984203554207d6c008d531ad467b%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636469542646255358&sdata=s6kHeirmxaeW%2BRTX%2BPLHZl6UriqamOJcUlofDk5UogM%3D&reserved=0" target="_blank">http://ghc.haskell.org/trac/ghc/ticket/14490#comment:31</a>></span></span><o:p></o:p></p>
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GHC <<a href="https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.haskell.org%2Fghc%2F&data=02%7C01%7Csimonpj%40microsoft.com%7C3556984203554207d6c008d531ad467b%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636469542646255358&sdata=Y9ezk0w89tcdtlLvJpgvYXgWc6iehBhs9kBfEREP9bM%3D&reserved=0" target="_blank">http://www.haskell.org/ghc/</a>><br>
The Glasgow Haskell Compiler<o:p></o:p></p>
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<o:p> </o:p></p>
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