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<div style="direction: ltr;font-family: Tahoma;color: #000000;font-size: 10pt;">Chandler,<br>
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Could you elaborate on "there is usually a better pattern to follow"?<br>
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I don't like the casts either and would prefer another way.<br>
<br>
Jack<br>
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<div style="direction: ltr;" id="divRpF407642"><font face="Tahoma" color="#000000" size="2"><b>From:</b> Chandler Carruth [chandlerc@google.com]<br>
<b>Sent:</b> Thursday, January 31, 2013 3:46 PM<br>
<b>To:</b> Carter, Jack<br>
<b>Cc:</b> Commit Messages and Patches for LLVM<br>
<b>Subject:</b> Re: [llvm] r173885 - This patch implements runtime ARM specific</font><br>
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// Not in an ITBlock to start with.<br>
ITState.CurPosition = ~0U;<br>
+<br>
+ // Set ELF header flags.<br>
+ // FIXME: This should eventually end up somewhere else where more<br>
+ // intelligent flag decisions can be made. For now we are just maintaining<br>
+ // the status quo for ARM and setting EF_ARM_EABI_VER5 as the default.<br>
+ MCELFStreamer &MES = static_cast<MCELFStreamer &>(Parser.getStreamer());<br>
+ MES.getAssembler().setELFHeaderEFlags(ELF::EF_ARM_EABI_VER5);<br>
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<div style="">Here, you don't test or check anything, you simply cast to MCELFStreamer, and run. This caused *really* strange bugs. I've fixed it in r174118 to use a proper check on the type of the MCStreamer here, but I would encourage you to audit some of
the other changes in this area to make sure there aren't other instances of this bug.</div>
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<div style="">In general, any use of static_cast<> to move through a dynamic class hierarchy in LLVM is pretty suspect, and something to investigate as there is usually a better pattern to follow.</div>
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<div style="">-Chandler</div>
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