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<p class="MsoNormal"><span style="mso-fareast-language:EN-US">I defer to SimonM but IIRC each stable name corresponds to an entry in the stable-name table; the index in the table is the “stable” thing in a stable name. So I bet that comparison compares these
indices.<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">If two stable names are pointer-equal, they presumably contain the same index into the table.<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">But is the reverse true? That is, can we be sure that two pointer-distinct stable name objects contain different indices?<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>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><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 <ghc-devs-bounces@haskell.org>
<b>On Behalf Of </b>David Feuer<br>
<b>Sent:</b> 19 August 2018 18:53<br>
<b>To:</b> ghc-devs <ghc-devs@haskell.org><br>
<b>Subject:</b> Stable name equality<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">eqStableName# is not currently defined as pointer equality. Is there some reason for this? My understanding is that there is a one-to-one correspondence between stable name objects and active stable name table entries, so pointer equality
should be sufficient. Am I missing something?<o:p></o:p></p>
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