<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Verdana;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin-top:6.0pt;
margin-right:0cm;
margin-bottom:6.0pt;
margin-left:0cm;
font-size:11.0pt;
font-family:"Calibri","sans-serif";
mso-fareast-language:EN-US;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:#0563C1;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:#954F72;
text-decoration:underline;}
p.Code, li.Code, div.Code
{mso-style-name:Code;
mso-style-link:"Code Char";
margin-top:0cm;
margin-right:0cm;
margin-bottom:0cm;
margin-left:36.0pt;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Courier New";
color:#1F497D;
mso-fareast-language:EN-US;}
span.CodeChar
{mso-style-name:"Code Char";
mso-style-link:Code;
font-family:"Courier New";
color:#1F497D;}
span.EmailStyle19
{mso-style-type:personal;
font-family:"Verdana","sans-serif";
color:windowtext;}
span.EmailStyle20
{mso-style-type:personal-reply;
font-family:"Verdana","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:72.0pt 72.0pt 72.0pt 72.0pt;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="EN-GB" link="#0563C1" vlink="#954F72">
<div class="WordSection1">
<p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1F497D">I’ve looked into this myself. I don’t think it’s actually anything wrong in gmp-wrappers. It’s because CmmBuildInfoTables expects all the info tables in the (CmmProc info_tbls
lbl g) to be defined in the graph g. <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1F497D">But Jan’s new optimisation to the stack overflow check (Note [Always false stack check] in CmmLayoutStack) ends up dropping a conditional branch, so a call to gc is eliminated,
and hence a proc point is eliminated, and we end up with an unused thing in info_tbls, which confuses CmmBuildInfoTables<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1F497D">Sigh. I don’t know why this only happens on Windows. I’m looking into a fix<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1F497D"><br>
Simon<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Verdana","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<div style="border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt">
<div>
<div style="border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm">
<p class="MsoNormal" style="margin:0cm;margin-bottom:.0001pt"><b><span lang="EN-US" style="mso-fareast-language:EN-GB">From:</span></b><span lang="EN-US" style="mso-fareast-language:EN-GB"> Simon Peyton-Jones
<br>
<b>Sent:</b> 15 November 2013 22:18<br>
<b>To:</b> ghc-devs@haskell.org<br>
<b>Subject:</b> bundle panic<o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-family:"Verdana","sans-serif"">Windows build is failing again in a new way. It was fine a couple of days ago. Does this ring any bells?<o:p></o:p></span></p>
<p class="Code">ghc-stage1.exe: panic! (the 'impossible' happened)<o:p></o:p></p>
<p class="Code"> (GHC version 7.7.20131107 for i386-unknown-mingw32):<o:p></o:p></p>
<p class="Code"> bundle<o:p></o:p></p>
<p class="MsoNormal"><span style="font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Verdana","sans-serif"">Simon<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
<p class="Code">"inplace/bin/ghc-stage1.exe" -static -H32m -O -Werror -Wall -H64m -O0 -package-name integer-gmp-0.5.1.0 -hide-all-packages -i -ilibraries/integer-gmp/. -ilibraries/integer-gmp/dist-install/build -ilibraries/integer-gmp/dist-install/build/autogen
-Ilibraries/integer-gmp/dist-install/build -Ilibraries/integer-gmp/dist-install/build/autogen -Ilibraries/integer-gmp/. -optP-include -optPlibraries/integer-gmp/dist-install/build/autogen/cabal_macros.h -package ghc-prim-0.3.1.0 -Wall -package-name integer-gmp
-XHaskell2010 -dcore-lint -no-user-package-db -rtsopts -Ilibraries/integer-gmp/mkGmpDerivedConstants/dist -c libraries/integer-gmp/cbits/gmp-wrappers.cmm -o libraries/integer-gmp/dist-install/build/cbits/gmp-wrappers.o<o:p></o:p></p>
<p class="Code">ghc-stage1.exe: panic! (the 'impossible' happened)<o:p></o:p></p>
<p class="Code"> (GHC version 7.7.20131107 for i386-unknown-mingw32):<o:p></o:p></p>
<p class="Code"> bundle<o:p></o:p></p>
<p class="Code"> c8 integer_cmm_importIntegerFromByteArrayzh [(c8,<o:p></o:p></p>
<p class="Code"> label: block{v c8}_info<o:p></o:p></p>
<p class="Code"> rep:StackRep [False, True, True, True]),<o:p></o:p></p>
<p class="Code"> (cg,<o:p></o:p></p>
<p class="Code"> label: block{v cg}_info<o:p></o:p></p>
<p class="Code"> rep:StackRep [False, True, True, True])]<o:p></o:p></p>
<p class="Code"><o:p> </o:p></p>
<p class="Code">Please report this as a GHC bug: <a href="http://www.haskell.org/ghc/reportabug">
http://www.haskell.org/ghc/reportabug</a><o:p></o:p></p>
<p class="Code"><o:p> </o:p></p>
<p class="Code">HEAD (master)$<span style="color:windowtext"><o:p></o:p></span></p>
</div>
</div>
</body>
</html>