Handle std::get<T>(...) for std::tuple<>

llvm-svn: 274422

2 files changed, 8 insertions, 0 deletions

diff --git a/libcxx/include/tuple b/libcxx/include/tuple
index 32f43805ff7..b0ab1c930b7 100644
--- a/libcxx/include/tuple
+++ b/libcxx/include/tuple
@@ -1013,6 +1013,11 @@ struct __find_exactly_one_checked {
     static_assert(value != __ambiguous,"type occurs more than once in type list");
 };
 
+template <class _T1>
+struct __find_exactly_one_checked<_T1> {
+    static_assert(!is_same<_T1, _T1>::value, "type not in empty type list");
+};
+
 } // namespace __find_detail;
 
 template <typename _T1, typename... _Args>
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type.fail.cpp
index 6375b77cd4a..74e6efd983b 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type.fail.cpp
@@ -20,6 +20,9 @@ void test_bad_index() {
     (void)std::get<long>(t1); // expected-note {{requested here}}
     (void)std::get<char>(t1); // expected-note {{requested here}}
         // expected-error@tuple:* 2 {{type occurs more than once}}
+    std::tuple<> t0;
+    (void)std::get<char*>(t0); // expected-node {{requested here}}
+        // expected-error@tuple:* 1 {{type not in empty type list}}
 }
 
 void test_bad_return_type() {