diff --git a/glib/tests/utils.c b/glib/tests/utils.c
index da97a92e2..6068cd9be 100644
--- a/glib/tests/utils.c
+++ b/glib/tests/utils.c
@@ -312,10 +312,18 @@ test_basic_bits (void)
     {
       guint naive_bit_storage_i = naive_bit_storage (i);
 
+      /* Test the g_bit_*() implementations against the compiler builtins (if
+       * available), and against a slow-but-correct ‘naive’ implementation.
+       * They should all agree.
+       *
+       * The macro and function versions of the g_bit_*() functions are tested,
+       * hence one call with the function name in brackets (to avoid it being
+       * expanded as a macro). */
 #if TEST_BUILTINS
       g_assert_cmpint (naive_bit_storage_i, ==, builtin_bit_storage (i));
 #endif
       g_assert_cmpint (naive_bit_storage_i, ==, g_bit_storage (i));
+      g_assert_cmpint (naive_bit_storage_i, ==, (g_bit_storage) (i));
 
       for (nth_bit = -3; nth_bit <= 2 + GLIB_SIZEOF_LONG * 8; nth_bit++)
         {
@@ -330,6 +338,8 @@ test_basic_bits (void)
 #endif
           g_assert_cmpint (naive_bit_nth_lsf_i_nth_bit, ==,
                            g_bit_nth_lsf (i, nth_bit));
+          g_assert_cmpint (naive_bit_nth_lsf_i_nth_bit, ==,
+                           (g_bit_nth_lsf) (i, nth_bit));
 
 #if TEST_BUILTINS
           g_assert_cmpint (naive_bit_nth_msf_i_nth_bit, ==,
@@ -337,6 +347,8 @@ test_basic_bits (void)
 #endif
           g_assert_cmpint (naive_bit_nth_msf_i_nth_bit, ==,
                            g_bit_nth_msf (i, nth_bit));
+          g_assert_cmpint (naive_bit_nth_msf_i_nth_bit, ==,
+                           (g_bit_nth_msf) (i, nth_bit));
         }
     }
 }