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<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">GHC devs,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">I wasn’t aware that we’d changed these.  Anyone know why?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">Simon<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal" style="margin-left:36.0pt"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Haskell-Cafe [mailto:haskell-cafe-bounces@haskell.org]
<b>On Behalf Of </b>Omari Norman<br>
<b>Sent:</b> 05 May 2015 15:55<br>
<b>To:</b> haskell Cafe<br>
<b>Subject:</b> [Haskell-cafe] Significant changes in -Wall for GHC 7.10<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:36.0pt"><o:p> </o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:6.0pt;margin-right:0cm;margin-bottom:12.0pt;margin-left:36.0pt">
I noticed some significant changes to the flags included with -Wall in GHC 7.10.  Many flags that were previously included in -Wall are now not included.  These include:<o:p></o:p></p>
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-fwarn-type-defaults<o:p></o:p></p>
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-fwarn-name-shadowing<o:p></o:p></p>
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-fwarn-missing-signatures<o:p></o:p></p>
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-fwarn-hi-shadowing<o:p></o:p></p>
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-fwarn-orphans<o:p></o:p></p>
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-fwarn-unused-do-bind<o:p></o:p></p>
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-fwarn-trustworthy-safe<o:p></o:p></p>
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I can't find any mention in the release notes of this change in behavior.<o:p></o:p></p>
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I was wondering what the rationale is for these changes?  Any link to relevant discussion would be appreciated if it exists.<br>
<br>
Also, what opinion do people have?  I previously kept my code -Wall clean, but sometimes that would be a pain.  For instance I would munge local names so they wouldn't trigger -fwarn-name-shadowing, and I would add signatures to integers so they wouldn't trigger
 -fwarn-type-defaults.  In fact, I only noticed this change in behavior in 7.10 because I was considering dumping -Wall, and when I looked at the 7.10 manual I saw that it does not enable -fwarn-name-shadowing.  (I still use 7.8 but Google pulled the 7.10 manual.) 
 Does this change indicate that people were finding -Wall too onerous and, thus, not using it?<br>
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I do remember reading complaints about -fwarn-unused-do-bind being added to -Wall, but I previously felt dirty about name shadowing though I wondered if munging names to avoid shadowing was actually worse.<o:p></o:p></p>
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