Use v.data() instead of &v[0] when SmallVector v might be empty.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@72210 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaInit.cpp b/lib/Sema/SemaInit.cpp
index 17113f6..f3ad2a1 100644
--- a/lib/Sema/SemaInit.cpp
+++ b/lib/Sema/SemaInit.cpp
@@ -1687,8 +1687,9 @@
   Desig.ClearExprs(*this);
 
   DesignatedInitExpr *DIE
-    = DesignatedInitExpr::Create(Context, &Designators[0], Designators.size(),
-                                 &InitExpressions[0], InitExpressions.size(),
+    = DesignatedInitExpr::Create(Context,
+                                 Designators.data(), Designators.size(),
+                                 InitExpressions.data(), InitExpressions.size(),
                                  Loc, GNUSyntax, Init.takeAs<Expr>());
   return Owned(DIE);
 }