Fix -Wunused-variable warning in Clang.cpp

llvm-svn: 331438
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 26789f1..25ce68b 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -1485,7 +1485,7 @@
       CmdArgs.push_back("-aarch64-enable-global-merge=true");
   }
 
-  if (Arg *A = Args.getLastArg(options::OPT_foutline)) {
+  if (Args.getLastArg(options::OPT_foutline)) {
     CmdArgs.push_back("-mllvm");
     CmdArgs.push_back("-enable-machine-outliner");
   }