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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D">I can’t reproduce this.&nbsp; With the enclosed module and HEAD, I get the warning; but when I add –fspec-constr-count=5, the warning goes away and I get the specialised
 rules.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D"><o:p>&nbsp;</o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D">Could Cabal not be passing on the flag or something?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D"><o:p>&nbsp;</o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D">Simon<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D"><o:p>&nbsp;</o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D"><o:p>&nbsp;</o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D">module Foo where<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D"><o:p>&nbsp;</o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D">data T = A | B | C | D | E<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D"><o:p>&nbsp;</o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D">f :: T -&gt; [Bool] -&gt; T<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D">f x ys | and ys = x<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D">f A ys = f B ys<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D">f B ys = f C ys<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D">f C ys = f D ys<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D">f D ys = f E ys<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D">f E ys = f A ys<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D"><o:p>&nbsp;</o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:&quot;Calibri&quot;,&quot;sans-serif&quot;;
color:#1F497D"><o:p>&nbsp;</o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:10.0pt;font-family:
&quot;Tahoma&quot;,&quot;sans-serif&quot;">From:</span></b><span lang="EN-US" style="font-size:10.0pt;
font-family:&quot;Tahoma&quot;,&quot;sans-serif&quot;"> glasgow-haskell-users-bounces@haskell.org [mailto:glasgow-haskell-users-bounces@haskell.org]
<b>On Behalf Of </b>Bryan O'Sullivan<br>
<b>Sent:</b> 29 August 2010 01:05<br>
<b>To:</b> glasgow-haskell-users@haskell.org<br>
<b>Subject:</b> Confusing warnings from GHC HEAD<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p>&nbsp;</o:p></p>
<p class="MsoNormal">I get a few dozen of these when building the text package, and they weren't present in 6.12 or earlier:<o:p></o:p></p>
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<p class="MsoNormal"><o:p>&nbsp;</o:p></p>
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<p class="MsoNormal"><span style="font-family:&quot;Courier New&quot;">SpecConstr</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-family:&quot;Courier New&quot;">&nbsp;&nbsp; &nbsp;Function `$wa1{v X5A2} [lid]'</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-family:&quot;Courier New&quot;">&nbsp;&nbsp; &nbsp; &nbsp;has three call patterns, but the limit is 2</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-family:&quot;Courier New&quot;">&nbsp;&nbsp; &nbsp;Use -fspec-constr-count=n to set the bound</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-family:&quot;Courier New&quot;">&nbsp;&nbsp; &nbsp;Use -dppr-debug to see specialisations</span><o:p></o:p></p>
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<p class="MsoNormal"><o:p>&nbsp;</o:p></p>
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<p class="MsoNormal">There are a few aspects to this that I find surprising.<o:p></o:p></p>
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I can't do anything with the Core name.<o:p></o:p> </li><li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
     mso-list:l0 level1 lfo1">
My cabal file contains&nbsp;-fspec-constr-count=5 just to be safe, but it doesn't help.<o:p></o:p>
</li></ul>
<p class="MsoNormal">I can't tell whether this is the compiler going a little off into the weeds, or whether I'm doing something wrong, but I appear to be unable to make the message go away.<o:p></o:p></p>
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<p class="MsoNormal"><o:p>&nbsp;</o:p></p>
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<p class="MsoNormal">Thanks,<o:p></o:p></p>
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<p class="MsoNormal">Bryan.<o:p></o:p></p>
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