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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Added Alexey to the list, he’s the OMP Maintainer, so hopefully he knows better
</span><span style="font-size:11.0pt;font-family:Wingdings;color:#1F497D">J</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p></o:p></span></p>
<p class="MsoNormal"><a name="_MailEndCompose"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></a></p>
<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> David Blaikie [mailto:dblaikie@gmail.com]
<br>
<b>Sent:</b> Friday, October 7, 2016 11:51 AM<br>
<b>To:</b> reviews+D25373+public+d8ec2a4bb41b17c6@reviews.llvm.org; Keane, Erich <erich.keane@intel.com>; cfe-commits@lists.llvm.org; david.majnemer@gmail.com; guy.benyei@intel.com<br>
<b>Cc:</b> junbuml@codeaurora.org<br>
<b>Subject:</b> Re: [PATCH] D25373: Fix for Bug 30639: CGDebugInfo Null dereference with OpenMP array access<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Could you explain how/why there's a null size expr? I would've thought it must have /some/ size for code generation purposes...<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Fri, Oct 7, 2016 at 11:33 AM Erich Keane <<a href="mailto:erich.keane@intel.com">erich.keane@intel.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">erichkeane created this revision.<br>
erichkeane added reviewers: cfe-commits, dblaikie, majnemer, gbenyei.<br>
erichkeane set the repository for this revision to rL LLVM.<br>
<br>
OpenMP creates a variable array type with a a null size-expr. The Debug generation failed to properly consider this case. This patch adds a null check to prevent a null dereference seg-fault in this case, plus adds a test.<br>
<br>
<br>
Repository:<br>
rL LLVM<br>
<br>
<a href="https://reviews.llvm.org/D25373" target="_blank">https://reviews.llvm.org/D25373</a><br>
<br>
Files:<br>
lib/CodeGen/CGDebugInfo.cpp<br>
test/CodeGenCXX/debug-info-openmp-array.cpp<br>
<br>
<br>
Index: lib/CodeGen/CGDebugInfo.cpp<br>
===================================================================<br>
--- lib/CodeGen/CGDebugInfo.cpp<br>
+++ lib/CodeGen/CGDebugInfo.cpp<br>
@@ -2181,7 +2181,8 @@<br>
Count = CAT->getSize().getZExtValue();<br>
else if (const auto *VAT = dyn_cast<VariableArrayType>(Ty)) {<br>
llvm::APSInt V;<br>
- if (VAT->getSizeExpr()->EvaluateAsInt(V, CGM.getContext()))<br>
+ if (VAT->getSizeExpr() &&<br>
+ VAT->getSizeExpr()->EvaluateAsInt(V, CGM.getContext()))<br>
Count = V.getExtValue();<br>
}<br>
<br>
Index: test/CodeGenCXX/debug-info-openmp-array.cpp<br>
===================================================================<br>
--- test/CodeGenCXX/debug-info-openmp-array.cpp<br>
+++ test/CodeGenCXX/debug-info-openmp-array.cpp<br>
@@ -0,0 +1,17 @@<br>
+// RUN: %clang -target x86_64-unknown-unknown -fverbose-asm -fopenmp -g -O0 -S -emit-llvm %s -o - | FileCheck %s<br>
+<br>
+<br>
+void f(int m) {<br>
+ int i;<br>
+ int cen[m];<br>
+#pragma omp parallel for<br>
+ for (i = 0; i < m; ++i) {<br>
+ cen[i] = i;<br>
+ }<br>
+}<br>
+<br>
+// CHECK: !DICompositeType(tag: DW_TAG_array_type,<br>
+// CHECK-NOT: size:<br>
+// CHECK-SAME: align: 32<br>
+// CHECK-SAME: elements: [[ELEM_TYPE:![0-9]+]]<br>
+// CHECK: !DISubrange(count: -1)<br>
<br>
<o:p></o:p></p>
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