diff --git a/tools/CIndex/CIndex.cpp b/tools/CIndex/CIndex.cpp
index 6fc7b53..de83547 100644
--- a/tools/CIndex/CIndex.cpp
+++ b/tools/CIndex/CIndex.cpp
@@ -1527,6 +1527,8 @@
 
   ASTUnit *CXXUnit = static_cast<ASTUnit *>(TU);
 
+  ASTUnit::ConcurrencyCheck Check(*CXXUnit);
+
   SourceLocation SLoc = cxloc::translateSourceLocation(Loc);
   CXCursor Result = MakeCXCursorInvalid(CXCursor_NoDeclFound);
   if (SLoc.isValid()) {
@@ -2052,6 +2054,8 @@
   if (!CXXUnit || !Tokens || !NumTokens)
     return;
 
+  ASTUnit::ConcurrencyCheck Check(*CXXUnit);
+  
   SourceRange R = cxloc::translateCXSourceRange(Range);
   if (R.isInvalid())
     return;
@@ -2175,6 +2179,8 @@
   if (!CXXUnit || !Tokens)
     return;
 
+  ASTUnit::ConcurrencyCheck Check(*CXXUnit);
+
   // Annotate all of the source locations in the region of interest that map
   SourceRange RegionOfInterest;
   RegionOfInterest.setBegin(