diff --git a/dlib/rand/rand_kernel_1.h b/dlib/rand/rand_kernel_1.h
index c545b5bd1..02faeb131 100644
--- a/dlib/rand/rand_kernel_1.h
+++ b/dlib/rand/rand_kernel_1.h
@@ -114,20 +114,12 @@ namespace dlib
             friend void serialize(
                 const rand_kernel_1& item, 
                 std::ostream& out
-            )
-            {
-                serialize(item.mt, out);
-                serialize(item.seed, out);
-            }
+            );
 
             friend void deserialize(
                 rand_kernel_1& item, 
                 std::istream& in 
-            )
-            {
-                deserialize(item.mt, in);
-                deserialize(item.seed, in);
-            }
+            );
 
         private:
             mt19937 mt;
@@ -148,6 +140,23 @@ namespace dlib
         static const bool value = true; 
     };
 
+    inline void serialize(
+        const rand_kernel_1& item, 
+        std::ostream& out
+    )
+    {
+        serialize(item.mt, out);
+        serialize(item.seed, out);
+    }
+
+    inline void deserialize(
+        rand_kernel_1& item, 
+        std::istream& in 
+    )
+    {
+        deserialize(item.mt, in);
+        deserialize(item.seed, in);
+    }
 }
 
 #endif // DLIB_RAND_KERNEl_1_
diff --git a/dlib/test/rand.cpp b/dlib/test/rand.cpp
index 36576dc44..1c39b26cf 100644
--- a/dlib/test/rand.cpp
+++ b/dlib/test/rand.cpp
@@ -218,6 +218,7 @@ namespace
         {
             dlog << LINFO << "testing kernel_1a";
             rand_test<dlib::rand::kernel_1a>();
+            rand_test<dlib::rand::float_1a>();
         }
     } a;