[c++1z] N4295: fold-expressions.

This is a new form of expression of the form:

  (expr op ... op expr)

where one of the exprs is a parameter pack. It expands into

  (expr1 op (expr2onwards op ... op expr))

(and likewise if the pack is on the right). The non-pack operand can be
omitted; in that case, an empty pack gives a fallback value or an error,
depending on the operator.

llvm-svn: 221573

1 files changed, 6 insertions, 0 deletions

diff --git a/clang/test/SemaCXX/cxx0x-compat.cpp b/clang/test/SemaCXX/cxx0x-compat.cpp
index ded51ab704b..bcf0cf11dc1 100644
--- a/clang/test/SemaCXX/cxx0x-compat.cpp
+++ b/clang/test/SemaCXX/cxx0x-compat.cpp
@@ -41,9 +41,15 @@ void h(size_t foo, size_t bar) {
 #define _x + 1
 char c = 'x'_x; // expected-warning {{will be treated as a user-defined literal suffix}}
 
+template<int ...N> int f() { // expected-warning {{C++11 extension}}
+  return (N + ...); // expected-warning {{C++1z extension}}
+}
+
 #else
 
 auto init_capture = [a(0)] {}; // expected-warning {{initialized lambda captures are incompatible with C++ standards before C++14}}
 static_assert(true); // expected-warning {{incompatible with C++ standards before C++1z}}
 
+template<int ...N> int f() { return (N + ...); } // expected-warning {{incompatible with C++ standards before C++1z}}
+
 #endif