Clean up cast


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@6174 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/ExecutionEngine/ExecutionEngine.cpp b/lib/ExecutionEngine/ExecutionEngine.cpp
index a3c3f47..0b5d19e 100644
--- a/lib/ExecutionEngine/ExecutionEngine.cpp
+++ b/lib/ExecutionEngine/ExecutionEngine.cpp
@@ -31,7 +31,7 @@
 GenericValue ExecutionEngine::getConstantValue(const Constant *C) {
   GenericValue Result;
 
-  if (ConstantExpr *CE = (ConstantExpr*)dyn_cast<ConstantExpr>(C))
+  if (ConstantExpr *CE = const_cast<ConstantExpr*>(dyn_cast<ConstantExpr>(C)))
     switch (CE->getOpcode()) {
     case Instruction::GetElementPtr: {
       Result = getConstantValue(cast<Constant>(CE->getOperand(0)));