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    <div class="moz-cite-prefix">Hi Yaron,<br>
        Yes I meant double destruction.<br>
      Vassil<br>
      On 03/08/14 20:08, Yaron Keren wrote:<br>
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        <div dir="ltr">Hi Vassil,</div>
        <div dir="ltr"><br>
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        <div dir="ltr">Do you mean double destruction (not deletion) of <span
style="font-family:arial,sans-serif;font-size:12.727272033691406px">MacroInfo
            first time in </span><span
            style="font-family:arial,sans-serif;font-size:12.727272033691406px">ReleaseMacroInfo </span><span
style="font-family:arial,sans-serif;font-size:12.727272033691406px">and
            the second time in </span>~Preprocessor via
           ~MacroInfoChain?</div>
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          <div dir="ltr">  while (MacroInfoChain *I = MIChainHead) {</div>
          <div dir="ltr">    MIChainHead = I->Next;</div>
          <div dir="ltr">    I->~MacroInfoChain();</div>
          <div dir="ltr">  }</div>
          <div><br>
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          <div>or something else?</div>
          <div><br>
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          <div>Yaron<br>
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      <div class="gmail_extra"><br>
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        <div class="gmail_quote">
          <div dir="ltr">2014-08-02 23:05 GMT+03:00 Vassil Vassilev <span
              dir="ltr"><<a moz-do-not-send="true"
                href="mailto:vvasilev@cern.ch" target="_blank">vvasilev@cern.ch</a>></span>:</div>
          <blockquote class="gmail_quote" style="margin:0 0 0
            .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi,<br>
              In cases where ReleaseMacroInfo gets called and it doesn't
            cleanup the Preprocessor's MIChainHead can lead to double
            deletion. I am sending the patch that fixes the problem for
            me.<br>
            Vassil<br>
            <br>
            <br>
            diff --git a/lib/Lex/PPDirectives.cpp
            b/lib/Lex/PPDirectives.cpp<br>
            index 5f38387..1a9b5eb 100644<br>
            --- a/lib/Lex/PPDirectives.cpp<br>
            +++ b/lib/Lex/PPDirectives.cpp<br>
            @@ -94,6 +94,14 @@ Preprocessor::AllocateVisibilityMacroDirective(SourceLocation
            Loc,<br>
             /// error in the macro definition.<br>
             void Preprocessor::ReleaseMacroInfo(MacroInfo *MI) {<br>
               // Don't try to reuse the storage; this only happens on
            error paths.<br>
            +<br>
            +  // If this is on the macro info chain, avoid double
            deletion on teardown.<br>
            +  while (MacroInfoChain *I = MIChainHead) {<br>
            +    if (&(I->MI) == MI)<br>
            +      I->Next = (I->Next) ? I->Next->Next : 0;<br>
            +    MIChainHead = I->Next;<br>
            +  }<br>
            +<br>
               MI->~MacroInfo();<br>
             }<br>
            <br>
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          </blockquote>
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