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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I think I know the difference. In both cases the issue was documented. That is like with ANSI aliasing rules – you can technically break it, but advised not
to do so in return of some benefits. Otherwise you can advise compiler not to do any assumptions about the aliasing. Here in this case default is safe and an optional way of doing the linking can give some benefits in return to some reasonable discipline.
It may need a better documentation though.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Stas<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Reid Kleckner [mailto:rnk@google.com]
<br>
<b>Sent:</b> Friday, April 25, 2014 10:48 PM<br>
<b>To:</b> Mekhanoshin, Stanislav<br>
<b>Cc:</b> Rafael Espíndola; llvm-commits; reviews+D3459+public+156625a4405c5834@reviews.llvm.org<br>
<b>Subject:</b> Re: [PATCH] Add -l option to llvm-link and allow linking by resolving symbols<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Fri, Apr 25, 2014 at 11:31 AM, Mekhanoshin, Stanislav <<a href="mailto:Stanislav.Mekhanoshin@amd.com" target="_blank">Stanislav.Mekhanoshin@amd.com</a>> wrote:<o:p></o:p></p>
<p class="MsoNormal">That is correct. The assumption is that such static initializers of unreferenced symbols do not have side effects. If I remember correctly Borland smart linker had the same limitation. Also, if I remember correctly LTO with Sun Solaris
was also limited by this.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I wish this was a reasonable assumption. However, we live in a dark world of great evil, where programs spawn threads from their dynamic initializers.<o:p></o:p></p>
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