Implement LWG#2436: 'Comparators for associative containers should always be CopyConstructible'

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@274235 91177308-0d34-0410-b5e6-96231b3b80d8

test/std/containers/associative/multimap/multimap.cons/compare_copy_constructible.fail.cpp

@@ -0,0 +1,29 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <map>
+
+// Check that std::multimap fails to instantiate if the comparison predicate is 
+// not copy-constructible. This is LWG issue 2436
+
+#include <map>
+
+template <class T>
+struct Comp {
+	bool operator () (const T& lhs, const T& rhs) const { return lhs < rhs; }
+
+	Comp () {}
+private:
+	Comp (const Comp &); // declared but not defined
+	};
+
+
+int main() {
+	std::multimap<int, int, Comp<int> > m;
+}