Silence a bunch (but not all) "variable written but not read" warnings
when building with assertions disabled.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137460 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/llvm-diff/DifferenceEngine.cpp b/tools/llvm-diff/DifferenceEngine.cpp
index ba2cec2..b240d8c 100644
--- a/tools/llvm-diff/DifferenceEngine.cpp
+++ b/tools/llvm-diff/DifferenceEngine.cpp
@@ -195,12 +195,12 @@
     DifferenceEngine::Context C(Engine, L, R);
 
     BasicBlock::iterator LI = L->begin(), LE = L->end();
-    BasicBlock::iterator RI = R->begin(), RE = R->end();
+    BasicBlock::iterator RI = R->begin();
 
     llvm::SmallVector<std::pair<Instruction*,Instruction*>, 20> TentativePairs;
 
     do {
-      assert(LI != LE && RI != RE);
+      assert(LI != LE && RI != R->end());
       Instruction *LeftI = &*LI, *RightI = &*RI;
 
       // If the instructions differ, start the more sophisticated diff