diff --git a/glib/gdataset.c b/glib/gdataset.c
index 452c48730..eef4be4ac 100644
--- a/glib/gdataset.c
+++ b/glib/gdataset.c
@@ -142,13 +142,13 @@
 
 /* datalist pointer accesses have to be carried out atomically */
 #define G_DATALIST_GET_POINTER(datalist)						\
-  ((GData*) ((gsize) g_atomic_pointer_get (datalist) & ~(gsize) G_DATALIST_FLAGS_MASK_INTERNAL))
+  ((GData*) ((guintptr) g_atomic_pointer_get (datalist) & ~(gsize) G_DATALIST_FLAGS_MASK_INTERNAL))
 
 #define G_DATALIST_SET_POINTER(datalist, pointer)       G_STMT_START {                           \
   gpointer _oldv = g_atomic_pointer_get (datalist);                                              \
   gpointer _newv;                                                                                \
   do {                                                                                           \
-    _newv = (gpointer) (((gsize) _oldv & G_DATALIST_FLAGS_MASK_INTERNAL) | (gsize) pointer);     \
+    _newv = (gpointer) (((gsize) _oldv & G_DATALIST_FLAGS_MASK_INTERNAL) | (guintptr) pointer);  \
   } while (!g_atomic_pointer_compare_and_exchange_full ((void**) datalist, _oldv,                \
                                                         _newv, &_oldv));                         \
 } G_STMT_END
diff --git a/gobject/gobject.c b/gobject/gobject.c
index 96aeab22c..793dbdddc 100644
--- a/gobject/gobject.c
+++ b/gobject/gobject.c
@@ -3447,7 +3447,7 @@ object_floating_flag_handler (GObject        *object,
       oldvalue = g_atomic_pointer_get (&object->qdata);
       while (!g_atomic_pointer_compare_and_exchange_full (
         (void**) &object->qdata, oldvalue,
-        (void *) ((gsize) oldvalue | OBJECT_FLOATING_FLAG),
+        (void *) ((guintptr) oldvalue | OBJECT_FLOATING_FLAG),
         &oldvalue))
         ;
       return (gsize) oldvalue & OBJECT_FLOATING_FLAG;
@@ -3455,7 +3455,7 @@ object_floating_flag_handler (GObject        *object,
       oldvalue = g_atomic_pointer_get (&object->qdata);
       while (!g_atomic_pointer_compare_and_exchange_full (
         (void**) &object->qdata, oldvalue,
-        (void *) ((gsize) oldvalue & ~(gsize) OBJECT_FLOATING_FLAG),
+        (void *) ((guintptr) oldvalue & ~(gsize) OBJECT_FLOATING_FLAG),
         &oldvalue))
         ;
       return (gsize) oldvalue & OBJECT_FLOATING_FLAG;
diff --git a/gobject/gparam.c b/gobject/gparam.c
index e067d6026..8974714ce 100644
--- a/gobject/gparam.c
+++ b/gobject/gparam.c
@@ -257,7 +257,7 @@ g_param_spec_unref (GParamSpec *pspec)
 void
 g_param_spec_sink (GParamSpec *pspec)
 {
-  gsize oldvalue;
+  guintptr oldvalue;
   g_return_if_fail (G_IS_PARAM_SPEC (pspec));
 
   oldvalue = g_atomic_pointer_and (&pspec->qdata, ~(gsize)PARAM_FLOATING_FLAG);
@@ -277,7 +277,7 @@ g_param_spec_sink (GParamSpec *pspec)
 GParamSpec*
 g_param_spec_ref_sink (GParamSpec *pspec)
 {
-  gsize oldvalue;
+  guintptr oldvalue;
   g_return_val_if_fail (G_IS_PARAM_SPEC (pspec), NULL);
 
   oldvalue = g_atomic_pointer_and (&pspec->qdata, ~(gsize)PARAM_FLOATING_FLAG);