Attributes: Avoid a big useless copy in the emitter

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@201251 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/utils/TableGen/ClangAttrEmitter.cpp b/utils/TableGen/ClangAttrEmitter.cpp
index 63225767c2284caf580692f9d2b2522cf393da72..cd812cb1e9dcc131d872053e2b410e7bc3bcfddc 100644 (file)
--- a/utils/TableGen/ClangAttrEmitter.cpp
+++ b/utils/TableGen/ClangAttrEmitter.cpp
@@ -607,7 +607,8 @@ namespace {
   };
 
   // Unique the enums, but maintain the original declaration ordering.
-  std::vector<std::string> uniqueEnumsInOrder(std::vector<std::string> enums) {
+  std::vector<std::string>
+  uniqueEnumsInOrder(const std::vector<std::string> &enums) {
     std::vector<std::string> uniques;
     std::set<std::string> unique_set(enums.begin(), enums.end());
     for (std::vector<std::string>::const_iterator i = enums.begin(),