Make use of const-correct ParseCommandLineOptions

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@150000 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/BackendUtil.cpp b/lib/CodeGen/BackendUtil.cpp
index 1707ec5..e244734 100644
--- a/lib/CodeGen/BackendUtil.cpp
+++ b/lib/CodeGen/BackendUtil.cpp
@@ -246,8 +246,7 @@
     CM = llvm::CodeModel::Default;
   }
 
-  std::vector<const char *> BackendArgs;
-  BackendArgs.reserve(16);
+  SmallVector<const char *, 16> BackendArgs;
   BackendArgs.push_back("clang"); // Fake program name.
   if (!CodeGenOpts.DebugPass.empty()) {
     BackendArgs.push_back("-debug-pass");
@@ -265,7 +264,7 @@
     BackendArgs.push_back("-global-merge=false");
   BackendArgs.push_back(0);
   llvm::cl::ParseCommandLineOptions(BackendArgs.size() - 1,
-                                    const_cast<char **>(&BackendArgs[0]));
+                                    BackendArgs.data());
 
   std::string FeaturesStr;
   if (TargetOpts.Features.size()) {