diff --git a/libcxx/include/variant b/libcxx/include/variant
index fb7cb2e20e5f..099e6c358499 100644
--- a/libcxx/include/variant
+++ b/libcxx/include/variant
@@ -578,7 +578,7 @@ private:
     constexpr decltype(auto) operator()(_Alts&&... __alts) const {
       __std_visit_exhaustive_visitor_check<
           _Visitor,
-          decltype(_VSTD::forward<_Alts>(__alts).__value)...>();
+          decltype((_VSTD::forward<_Alts>(__alts).__value))...>();
       return __invoke_constexpr(_VSTD::forward<_Visitor>(__visitor),
                                 _VSTD::forward<_Alts>(__alts).__value...);
     }
diff --git a/libcxx/test/std/utilities/variant/variant.visit/visit.pass.cpp b/libcxx/test/std/utilities/variant/variant.visit/visit.pass.cpp
index 46d225883ae9..408a65c0903f 100644
--- a/libcxx/test/std/utilities/variant/variant.visit/visit.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.visit/visit.pass.cpp
@@ -283,9 +283,20 @@ void test_exceptions() {
 #endif
 }
 
+// See http://llvm.org/PR31916
+void test_caller_accepts_nonconst() {
+  struct A {};
+  struct Visitor {
+    void operator()(A&) {}
+  };
+  std::variant<A> v;
+  std::visit(Visitor{}, v);
+}
+
 int main() {
   test_call_operator_forwarding();
   test_argument_forwarding();
   test_constexpr();
   test_exceptions();
+  test_caller_accepts_nonconst();
 }