Implement n3789; constexpr support in named function objects

llvm-svn: 191626
diff --git a/libcxx/test/utilities/function.objects/arithmetic.operations/divides.pass.cpp b/libcxx/test/utilities/function.objects/arithmetic.operations/divides.pass.cpp
index 5eeba18..74298f2 100644
--- a/libcxx/test/utilities/function.objects/arithmetic.operations/divides.pass.cpp
+++ b/libcxx/test/utilities/function.objects/arithmetic.operations/divides.pass.cpp
@@ -27,5 +27,11 @@
     assert(f2(36, 4) == 9);
     assert(f2(36.0, 4) == 9);
     assert(f2(18, 4.0) == 4.5); // exact in binary
+
+    constexpr int foo = std::divides<int> () (3, 2);
+    static_assert ( foo == 1, "" );
+
+    constexpr int bar = std::divides<> () (3.0, 2);
+    static_assert ( bar == 1, "" );
 #endif
 }