Take lock before removing a node from MDNodeSet.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81356 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 5 insertions, 1 deletions

diff --git a/lib/VMCore/Metadata.cpp b/lib/VMCore/Metadata.cpp
index 8e025b6d7a..1163b4709c 100644
--- a/lib/VMCore/Metadata.cpp
+++ b/lib/VMCore/Metadata.cpp
@@ -115,7 +115,11 @@ void MDNode::dropAllReferences() {
 }
 
 MDNode::~MDNode() {
-  getType()->getContext().pImpl->MDNodeSet.RemoveNode(this);
+  {
+    LLVMContextImpl *pImpl = getType()->getContext().pImpl;
+    sys::SmartScopedWriter<true> Writer(pImpl->ConstantsLock);
+    pImpl->MDNodeSet.RemoveNode(this);
+  }
   dropAllReferences();
 }