Remove type-punning warning in GRExprEngine.  No functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@58292 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/GRExprEngine.cpp b/lib/Analysis/GRExprEngine.cpp
index 67dd79a..e843f5d 100644
--- a/lib/Analysis/GRExprEngine.cpp
+++ b/lib/Analysis/GRExprEngine.cpp
@@ -2178,10 +2178,13 @@
     
       assert (B->isCompoundAssignmentOp());
 
-      if (Op >= BinaryOperator::AndAssign)
-        ((int&) Op) -= (BinaryOperator::AndAssign - BinaryOperator::And);
-      else
-        ((int&) Op) -= BinaryOperator::MulAssign;  
+      if (Op >= BinaryOperator::AndAssign) {
+        Op = (BinaryOperator::Opcode) (Op - (BinaryOperator::AndAssign - 
+                                             BinaryOperator::And));
+      }
+      else {
+        Op = (BinaryOperator::Opcode) (Op - BinaryOperator::MulAssign);
+      }
           
       // Perform a load (the LHS).  This performs the checks for
       // null dereferences, and so on.