<div dir="ltr">Hi Xu,Chiheng,<div><br></div><div>Locally I'm using this patch to work around the issue. I'm not yet sure if it's the right fix since I haven't had cycles to dig into the root cause yet, but it does get me past the seg faults in the scenarios I'm using. This patch is against the llvm repo:</div>
<div><br></div><div><a href="https://llvm.org/svn/llvm-project/llvm/trunk@203176">https://llvm.org/svn/llvm-project/llvm/trunk@203176</a> <br></div><div><br></div><div><div><font face="courier new, monospace" size="1">--- a/lib/MC/MCExternalSymbolizer.cpp</font></div>
<div><font face="courier new, monospace" size="1">+++ b/lib/MC/MCExternalSymbolizer.cpp</font></div><div><font face="courier new, monospace" size="1">@@ -132,7 +132,8 @@ bool MCExternalSymbolizer::tryAddingSymbolicOperand(MCInst &MI,</font></div>
<div><font face="courier new, monospace" size="1"> Expr = MCConstantExpr::Create(0, Ctx);</font></div><div><font face="courier new, monospace" size="1"> }</font></div><div><font face="courier new, monospace" size="1"> </font></div>
<div><font face="courier new, monospace" size="1">- Expr = RelInfo->createExprForCAPIVariantKind(Expr, SymbolicOp.VariantKind);</font></div><div><font face="courier new, monospace" size="1">+ if (RelInfo)</font></div>
<div><font face="courier new, monospace" size="1">+ Expr = RelInfo->createExprForCAPIVariantKind(Expr, SymbolicOp.VariantKind);</font></div><div><font face="courier new, monospace" size="1"> if (!Expr)</font></div>
<div><font face="courier new, monospace" size="1"> return false;</font></div></div></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Thu, Mar 6, 2014 at 6:05 AM, Xu,Chiheng <span dir="ltr"><<a href="mailto:chiheng.xu@gmail.com" target="_blank">chiheng.xu@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi, list,<br>
When I use lastest LLDB(and Clang/LLVM) to debug a hello world program<br>
on Fedora 18 x86_64 Linux. I encounter a crash of LLDB. I have<br>
debugged LLDB using gdb-7.6.2, and found that the offending line is :<br>
<br>
Breakpoint 3, llvm::MCExternalSymbolizer::tryAddingSymbolicOperand (<br>
this=0x7fe470000c50, MI=..., cStream=..., Value=258220247920,<br>
Address=258220234131, IsBranch=true, Offset=1, InstSize=4)<br>
at /mnt/work/llvm/lib/MC/MCExternalSymbolizer.cpp:135<br>
135 Expr = RelInfo->createExprForCAPIVariantKind(Expr,<br>
SymbolicOp.VariantKind);<br>
<br>
where RelInfo (of type std::unique_ptr<MCRelocationInfo>) is 0, so<br>
LLDB crash, I'm new to this, can some one explain this to me.<br>
<br>
LLDB does not has this problem about 2 weeks ago.<br>
Attached is the debug log.<br>
<br>
Thank you.<br>
<span class="HOEnZb"><font color="#888888"><br>
--<br>
Xu,Chiheng(徐持恒)<br>
</font></span><br>_______________________________________________<br>
lldb-dev mailing list<br>
<a href="mailto:lldb-dev@cs.uiuc.edu">lldb-dev@cs.uiuc.edu</a><br>
<a href="http://lists.cs.uiuc.edu/mailman/listinfo/lldb-dev" target="_blank">http://lists.cs.uiuc.edu/mailman/listinfo/lldb-dev</a><br>
<br></blockquote></div><br><br clear="all"><div><br></div>-- <br><div dir="ltr"><table cellspacing="0" cellpadding="0" style="color:rgb(136,136,136);font-family:'Times New Roman'"><tbody><tr style="color:rgb(85,85,85);font-family:sans-serif;font-size:small">
<td nowrap style="border-top-style:solid;border-top-color:rgb(213,15,37);border-top-width:2px">Todd Fiala |</td><td nowrap style="border-top-style:solid;border-top-color:rgb(51,105,232);border-top-width:2px"> Software Engineer |</td>
<td nowrap style="border-top-style:solid;border-top-color:rgb(0,153,57);border-top-width:2px"> <a href="mailto:tfiala@google.com" style="color:rgb(17,85,204)" target="_blank"><span style="background-color:rgb(255,255,204);color:rgb(34,34,34);background-repeat:initial initial">tfiala@google.com</span></a> |</td>
<td nowrap style="border-top-style:solid;border-top-color:rgb(238,178,17);border-top-width:2px"><font color="#1155cc"> <a>650-943-3180</a></font></td></tr></tbody></table><br></div>
</div>