diff --git a/llvm/tools/llvm-c-test/echo.cpp b/llvm/tools/llvm-c-test/echo.cpp
--- a/llvm/tools/llvm-c-test/echo.cpp
+++ b/llvm/tools/llvm-c-test/echo.cpp
@@ -805,20 +805,20 @@
       case LLVMShuffleVector: {
         LLVMValueRef Agg0 = CloneValue(LLVMGetOperand(Src, 0));
         LLVMValueRef Agg1 = CloneValue(LLVMGetOperand(Src, 1));
-        unsigned num_mask_elts = LLVMGetNumMaskElements(Src);
-        if (num_mask_elts > 8)
+        unsigned NumMaskElts = LLVMGetNumMaskElements(Src);
+        if (NumMaskElts > 8)
           report_fatal_error(
               "ShuffleVector: Expected no more than 8 mask elements");
-        LLVMValueRef mask_elts[8];
-        for (unsigned i = 0; i < num_mask_elts; i++) {
-          int val = LLVMGetMaskValue(Src, i);
-          if (val == LLVMUndefMaskElem) {
-            mask_elts[i] = LLVMGetUndef(LLVMInt64Type());
+        LLVMValueRef MaskElts[8];
+        for (unsigned i = 0; i < NumMaskElts; i++) {
+          int Val = LLVMGetMaskValue(Src, i);
+          if (Val == LLVMUndefMaskElem) {
+            MaskElts[i] = LLVMGetUndef(LLVMInt64Type());
           } else {
-            mask_elts[i] = LLVMConstInt(LLVMInt64Type(), val, true);
+            MaskElts[i] = LLVMConstInt(LLVMInt64Type(), Val, true);
           }
         }
-        LLVMValueRef Mask = LLVMConstVector(&mask_elts[0], num_mask_elts);
+        LLVMValueRef Mask = LLVMConstVector(&MaskElts[0], NumMaskElts);
         Dst = LLVMBuildShuffleVector(Builder, Agg0, Agg1, Mask, Name);
         break;
       }