diff --git a/lib/Differentiator/ReverseModeVisitor.cpp b/lib/Differentiator/ReverseModeVisitor.cpp
index 7146d070f..966538af9 100644
--- a/lib/Differentiator/ReverseModeVisitor.cpp
+++ b/lib/Differentiator/ReverseModeVisitor.cpp
@@ -216,7 +216,8 @@ Expr* getArraySizeExpr(const ArrayType* AT, ASTContext& context,
          ++i) {
       auto* overloadParam = overloadParams[i];
       auto* gradientParam = gradientParams[i];
-      auto* init = m_Sema.ImpCastExprToType(BuildDeclRef(overloadParam), gradientParam->getType(), clang::CK_BitCast).get();
+      TypeSourceInfo* typeInfo = m_Context.getTrivialTypeSourceInfo(gradientParam->getType());
+      auto* init = m_Sema.BuildCStyleCastExpr(noLoc, typeInfo, noLoc, BuildDeclRef(overloadParam)).get();
 
       auto* gradientVD =
           BuildGlobalVarDecl(gradientParam->getType(), gradientParam->getName(),