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<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">I’m puzzled. Internals.hs defines a newtype<o:p></o:p></span></p>
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<p class="MsoNormal" style="text-indent:36.0pt"><span style="font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">newtype CGid = CGid Word32<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">A value of this type is needed to fill in the child_group field of CreateProcess. If you don’t export it, you could never initialise this field to
anything other than Nothing, so why do you have it?<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Looks to me as if the warning has nailed a real bug<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Simon<o:p></o:p></span></p>
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<p class="MsoNormal"><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"> michael.snoyman@gmail.com [mailto:michael.snoyman@gmail.com]
<b>On Behalf Of </b>Michael Snoyman<br>
<b>Sent:</b> 02 November 2015 13:34<br>
<b>To:</b> Simon Peyton Jones<br>
<b>Cc:</b> ghc-devs@haskell.org<br>
<b>Subject:</b> Re: process library broken on Windows<o:p></o:p></span></p>
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I didn't read closely enough: I see now that it's a warning, not an error. I initially didn't export that constructor since it's only present on Windows for API compatibility, but will never be used. Since this is just the internals module, I can export it,
but my preference would in fact be to leave it as-is with the warning. Two alternatives:<o:p></o:p></p>
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1. Create a new hidden module that creates and exports the type constructor, just to hide the warning. I'm -1 on that, since that's extra compile time everyone has to endure just for warning avoidance.<o:p></o:p></p>
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2. base could export CGid for Windows (currently, it does not).<o:p></o:p></p>
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On Mon, Nov 2, 2015 at 5:17 AM, Michael Snoyman <<a href="mailto:michael@snoyman.com" target="_blank">michael@snoyman.com</a>> wrote:<o:p></o:p></p>
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I'll look into this. I just made a new release of process, and was certain I tested on Windows, but perhaps something changed between that commit and release.<o:p></o:p></p>
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On Mon, Nov 2, 2015 at 5:15 AM, Simon Peyton Jones <<a href="mailto:simonpj@microsoft.com" target="_blank">simonpj@microsoft.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I’m getting this on HEAD in te ‘<o:p></o:p></p>
<p>libraries\process\System\Process\Internals.hs:106:16: warning:<o:p></o:p></p>
<p> Defined but not used: data constructor ‘CGid’<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Indeed it looks as if CGId(..) should be exported, else createProcess is unusuable. This looks like the right change. Would someone like to check and make the change<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Simon<o:p></o:p></p>
<p>diff --git a/System/Process/Internals.hs b/System/Process/Internals.hs<o:p></o:p></p>
<p>index 5575ac4..3e23ad5 100644<o:p></o:p></p>
<p>--- a/System/Process/Internals.hs<o:p></o:p></p>
<p>+++ b/System/Process/Internals.hs<o:p></o:p></p>
<p>@@ -37,6 +37,8 @@ module System.Process.Internals (<o:p></o:p></p>
<p>#if !defined(mingw32_HOST_OS) && !defined(__MINGW32__)<o:p></o:p></p>
<p> pPrPr_disableITimers, c_execvpe,<o:p></o:p></p>
<p> ignoreSignal, defaultSignal,<o:p></o:p></p>
<p>+#else<o:p></o:p></p>
<p>+ CGid(..), GroupID, UserID,<o:p></o:p></p>
<p>#endif<o:p></o:p></p>
<p> withFilePathException, withCEnvironment,<o:p></o:p></p>
<p> translate,<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">_______________________________________________<br>
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