diff --git a/gc.c b/gc.c
index 99de0aa..df58cfb 100644
--- a/gc.c
+++ b/gc.c
@@ -484,9 +484,9 @@ builtin_fn_t *get_builtin_fn(value_t v)
   return _get_builtin_fn(v);
 }
 
-static size_t dbj2_hash(uint8_t *bytes, size_t size)
+static fixnum_t dbj2_hash(uint8_t *bytes, size_t size)
 {
-  size_t hash = 5381;
+  fixnum_t hash = 5381;
 
   for (size_t i = 0; i < size; ++i)
   {
@@ -498,10 +498,29 @@ static size_t dbj2_hash(uint8_t *bytes, size_t size)
 
 static value_t _get_hash_value(value_t v, seen_value_t *seen)
 {
-  seen_value_t new_seen = { v, seen };
-
-  if (is_object(v) && !(is_float(v) || is_byte_string(v) || is_builtin_fn(v)))
+  if (is_float(v))
   {
+    double d = _get_float(v);
+    return fixnum_value(dbj2_hash((uint8_t*)&d, sizeof d));
+  }
+  else if (is_byte_string(v))
+  {
+    byte_string_t *str = _get_byte_string(v);
+    return fixnum_value(dbj2_hash(str->bytes, str->size));
+  }
+  else if (is_builtin_fn(v))
+  {
+    return fixnum_value((uintptr_t)_get_builtin_fn(v) >> 2);
+  }
+  else if (!is_object(v))
+  {
+    /* Non-objects compare by value */
+    return fixnum_value(v + (v >> 2));
+  }
+  else
+  {
+    seen_value_t new_seen = { v, seen };
+
     for (seen_value_t *sv = seen; sv; sv = sv->prev)
     {
       if (v == sv->value)
@@ -509,53 +528,34 @@ static value_t _get_hash_value(value_t v, seen_value_t *seen)
         return 0;
       }
     }
-  }
 
-  if (!is_object(v))
-  {
-    /* Non-objects compare by value */
-    return fixnum_value(v ^ (v >> 2));
-  }
-  else if (is_float(v))
-  {
-    double d = _get_float(v);
-    return fixnum_value(dbj2_hash((uint8_t*)&d, sizeof d));
-  }
-  else if (is_builtin_fn(v))
-  {
-    return fixnum_value((uintptr_t)_get_builtin_fn(v) >> 2);
-  }
-  else if (is_pair(v))
-  {
-    /* Lists and trees compare by value, not reference. */
-    value_t seed = fixnum_value(0);
-    seed = combine_hash_values(seed, _get_hash_value(_CAR(v), &new_seen));
-    seed = combine_hash_values(seed, _get_hash_value(_CDR(v), &new_seen));
-    return seed;
-  }
-  else if (is_box(v) || is_weak_box(v))
-  {
-    /* Boxes compare by value, not by reference. */
-    return _get_hash_value(_get_box(v)->value, &new_seen);
-  }
-  else if (is_byte_string(v))
-  {
-    byte_string_t *str = _get_byte_string(v);
-    return fixnum_value(dbj2_hash(str->bytes, str->size));
-  }
-  else if (is_vector(v))
-  {
-    /* Vectors compare by reference. */
-    return _get_vector(v)->hash;
-  }
-  else if (is_struct(v))
-  {
-    /* Structures compare by reference. */
-    return _get_struct(v)->hash;
-  }
-  else /* unknown object type */
-  {
-    return _get_hash_value(_get_object(v)->tag, &new_seen);
+    if (is_pair(v))
+    {
+      /* Lists and trees compare by value, not reference. */
+      value_t seed = fixnum_value(0);
+      seed = combine_hash_values(seed, _get_hash_value(_CAR(v), &new_seen));
+      seed = combine_hash_values(seed, _get_hash_value(_CDR(v), &new_seen));
+      return seed;
+    }
+    else if (is_box(v) || is_weak_box(v))
+    {
+      /* Boxes compare by value, not by reference. */
+      return _get_hash_value(_get_box(v)->value, &new_seen);
+    }
+    else if (is_vector(v))
+    {
+      /* Vectors compare by reference. */
+      return _get_vector(v)->hash;
+    }
+    else if (is_struct(v))
+    {
+      /* Structures compare by reference. */
+      return _get_struct(v)->hash;
+    }
+    else /* unknown object type */
+    {
+      return _get_hash_value(_get_object(v)->tag, &new_seen);
+    }
   }
 }