I have reverted all contributions made by Jesse Towner in revision 110724

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@119383 91177308-0d34-0410-b5e6-96231b3b80d8

include/__config

@@ -144,6 +144,10 @@ typedef __char32_t char32_t;
 #define _LIBCPP_HAS_NO_VARIADICS
 #endif
 
+#if !(__has_feature(cxx_trailing_return))
+#define _LIBCPP_HAS_NO_TRAILING_RETURN
+#endif
+
 #if __has_feature(cxx_inline_namespaces)
 #define _LIBCPP_BEGIN_NAMESPACE_STD namespace std {inline namespace _LIBCPP_NAMESPACE {
 #define _LIBCPP_END_NAMESPACE_STD  } }
@@ -190,6 +194,8 @@ using namespace _LIBCPP_NAMESPACE;
 
 #else  // __GXX_EXPERIMENTAL_CXX0X__
 
+#define _LIBCPP_HAS_NO_TRAILING_RETURN
+
 #if !(__GNUC__ >= 4 && __GNUC_MINOR__ >= 3)
 #define _LIBCPP_HAS_NO_RVALUE_REFERENCES
 #endif