Bump up the initial vector size to avoid having to grow the vector more often.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@149945 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGExprConstant.cpp b/lib/CodeGen/CGExprConstant.cpp
index 52ae9ee..ccb4b93 100644
--- a/lib/CodeGen/CGExprConstant.cpp
+++ b/lib/CodeGen/CGExprConstant.cpp
@@ -40,7 +40,7 @@
   bool Packed;
   CharUnits NextFieldOffsetInChars;
   CharUnits LLVMStructAlignment;
-  SmallVector<llvm::Constant *, 16> Elements;
+  SmallVector<llvm::Constant *, 32> Elements;
 public:
   static llvm::Constant *BuildStruct(CodeGenModule &CGM, CodeGenFunction *CGF,
                                      InitListExpr *ILE);