diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -348,6 +348,10 @@
 static cl::opt<bool> ClOpt("asan-opt", cl::desc("Optimize instrumentation"),
                            cl::Hidden, cl::init(true));
 
+static cl::opt<bool> ClOptimizeCallbacks("asan-optimize-callbacks",
+                                         cl::desc("Optimize callbacks"),
+                                         cl::Hidden, cl::init(false));
+
 static cl::opt<bool> ClOptSameTemp(
     "asan-opt-same-temp", cl::desc("Instrument the same temp just once"),
     cl::Hidden, cl::init(true));
@@ -634,6 +638,7 @@
     C = &(M.getContext());
     LongSize = M.getDataLayout().getPointerSizeInBits();
     IntptrTy = Type::getIntNTy(*C, LongSize);
+    Int8PtrTy = Type::getInt8PtrTy(*C);
     TargetTriple = Triple(M.getTargetTriple());
 
     Mapping = getShadowMapping(TargetTriple, LongSize, this->CompileKernel);
@@ -724,6 +729,7 @@
   bool UseAfterScope;
   AsanDetectStackUseAfterReturnMode UseAfterReturn;
   Type *IntptrTy;
+  Type *Int8PtrTy;
   ShadowMapping Mapping;
   FunctionCallee AsanHandleNoReturnFunc;
   FunctionCallee AsanPtrCmpFunction, AsanPtrSubFunction;