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diff --git a/test/SemaCXX/libstdcxx_pair_swap_hack.cpp b/test/SemaCXX/libstdcxx_pair_swap_hack.cpp
new file mode 100644
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+++ b/test/SemaCXX/libstdcxx_pair_swap_hack.cpp
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+// This is a test for an egregious hack in Clang that works around
+// an issue with GCC's <utility> implementation. std::pair::swap
+// has an exception specification that makes an unqualified call to
+// swap. This is invalid, because it ends up calling itself with
+// the wrong number of arguments.
+//
+// The same problem afflicts a bunch of other class templates. Those
+// affected are array, pair, priority_queue, stack, and queue.
+
+// RUN: %clang_cc1 -fsyntax-only %s -std=c++11 -verify -fexceptions -fcxx-exceptions -DCLASS=array
+// RUN: %clang_cc1 -fsyntax-only %s -std=c++11 -verify -fexceptions -fcxx-exceptions -DCLASS=pair
+// RUN: %clang_cc1 -fsyntax-only %s -std=c++11 -verify -fexceptions -fcxx-exceptions -DCLASS=priority_queue
+// RUN: %clang_cc1 -fsyntax-only %s -std=c++11 -verify -fexceptions -fcxx-exceptions -DCLASS=stack
+// RUN: %clang_cc1 -fsyntax-only %s -std=c++11 -verify -fexceptions -fcxx-exceptions -DCLASS=queue
+
+// MSVC's standard library uses a very similar pattern that relies on delayed
+// parsing of exception specifications.
+//
+// RUN: %clang_cc1 -fsyntax-only %s -std=c++11 -verify -fexceptions -fcxx-exceptions -DCLASS=array -DMSVC
+
+#ifdef BE_THE_HEADER
+
+#pragma GCC system_header
+namespace std {
+  template<typename T> void swap(T &, T &);
+  template<typename T> void do_swap(T &a, T &b) noexcept(noexcept(swap(a, b))) {
+    swap(a, b);
+  }
+
+  template<typename A, typename B> struct CLASS {
+#ifdef MSVC
+    void swap(CLASS &other) noexcept(noexcept(do_swap(member, other.member)));
+#endif
+    A member;
+#ifndef MSVC
+    void swap(CLASS &other) noexcept(noexcept(swap(member, other.member)));
+#endif
+  };
+
+//  template<typename T> void do_swap(T &, T &);
+//  template<typename A> struct vector {
+//    void swap(vector &other) noexcept(noexcept(do_swap(member, other.member)));
+//    A member;
+//  };
+}
+
+#else
+
+#define BE_THE_HEADER
+#include __FILE__
+
+struct X {};
+using PX = std::CLASS<X, X>;
+using PI = std::CLASS<int, int>;
+void swap(X &, X &) noexcept;
+PX px;
+PI pi;
+
+static_assert(noexcept(px.swap(px)), "");
+static_assert(!noexcept(pi.swap(pi)), "");
+
+namespace sad {
+  template<typename T> void swap(T &, T &);
+
+  template<typename A, typename B> struct CLASS {
+    void swap(CLASS &other) noexcept(noexcept(swap(*this, other))); // expected-error {{too many arguments}} expected-note {{declared here}}
+  };
+
+  CLASS<int, int> pi;
+
+  static_assert(!noexcept(pi.swap(pi)), ""); // expected-note {{in instantiation of}}
+}
+
+#endif