Added tests to the sequence containers for for LWG Issue #2263. Comparing iterators and allocator pointers with different const-character. No changes to libc++

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@203479 91177308-0d34-0410-b5e6-96231b3b80d8

test/containers/sequences/array/iterators.pass.cpp

@@ -72,10 +72,23 @@ int main()
         C::const_iterator cii{};
         assert ( ii1 == ii2 );
         assert ( ii1 == ii4 );
-        assert ( ii1 == cii );
 
-        assert ( !(ii1 != ii2 ));
-        assert ( !(ii1 != cii ));
+        assert (!(ii1 != ii2 ));
+
+        assert ( (ii1 == cii ));
+        assert ( (cii == ii1 ));
+        assert (!(ii1 != cii ));
+        assert (!(cii != ii1 ));
+        assert (!(ii1 <  cii ));
+        assert (!(cii <  ii1 ));
+        assert ( (ii1 <= cii ));
+        assert ( (cii <= ii1 ));
+        assert (!(ii1 >  cii ));
+        assert (!(cii >  ii1 ));
+        assert ( (ii1 >= cii ));
+        assert ( (cii >= ii1 ));
+        assert (cii - ii1 == 0);
+        assert (ii1 - cii == 0);
 
         C c;
         assert ( c.begin()   == std::begin(c));