1 files changed, 24 insertions, 0 deletions
diff --git a/gcc/testsuite/g++.dg/cpp0x/decltype19.C b/gcc/testsuite/g++.dg/cpp0x/decltype19.C
new file mode 100644
index 000000000..41d602f34
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/decltype19.C
@@ -0,0 +1,24 @@
+// PR c++/42013
+
+template<typename _Tp>
+  _Tp
+__attribute ((const)) declval();
+
+template<typename _Tp, typename _Up>
+  struct common_type
+  {
+    typedef __decltype(true  ? declval<_Tp>() : declval<_Up>()) typet;
+    typedef __decltype(false ? declval<_Tp>() : declval<_Up>()) typef;
+  };
+
+template<typename, typename> struct is_same;
+
+template<typename _Tp> struct is_same<_Tp, _Tp> { typedef _Tp type; };
+
+void f()
+{
+  typedef common_type<int, const int>::typet typet;
+  typedef common_type<int, const int>::typef typef;
+
+  typedef is_same<typet, typef>::type type;
+}