diff --git a/include/fmt/core.h b/include/fmt/core.h
index b3f969a9..184d039f 100644
--- a/include/fmt/core.h
+++ b/include/fmt/core.h
@@ -1460,7 +1460,7 @@ template <typename T, typename U> constexpr const U& check(const U& val) {
 template <bool IS_PACKED, typename Context, type, typename T,
           FMT_ENABLE_IF(IS_PACKED)>
 constexpr value<Context> make_arg(const T& val) {
-  return check<T>(arg_mapper<Context>().map(val));
+  return detail::check<T>(arg_mapper<Context>().map(val));
 }
 
 template <bool IS_PACKED, typename Context, type, typename T,
diff --git a/test/core-test.cc b/test/core-test.cc
index 6c395515..5114f226 100644
--- a/test/core-test.cc
+++ b/test/core-test.cc
@@ -471,7 +471,7 @@ TEST(FormatDynArgsTest, NamedArgByRef) {
   fmt::dynamic_format_arg_store<fmt::format_context> store;
   char band[] = "Rolling Stones";
   store.push_back(fmt::arg("band", std::cref(band)));
-  band[9] = 'c'; // Changing band affects the output.
+  band[9] = 'c';  // Changing band affects the output.
   EXPECT_EQ(fmt::vformat("{band}", store), "Rolling Scones");
 }
 
@@ -690,9 +690,10 @@ TYPED_TEST(IsStringTest, IsString) {
   EXPECT_FALSE(fmt::detail::is_string<my_ns::non_string>::value);
 }
 
-TEST(CoreTest, Format) {
-  EXPECT_EQ(fmt::format("{}", 42), "42");
-}
+TEST(CoreTest, Format) { EXPECT_EQ(fmt::format("{}", 42), "42"); }
+
+template <typename T> void check(T);
+TEST(CoreTest, ADL) { EXPECT_EQ(fmt::format("{}", test_struct()), "test"); }
 
 TEST(CoreTest, FormatTo) {
   std::string s;