diff --git a/gio/ChangeLog b/gio/ChangeLog
index d3525f857..b893318da 100644
--- a/gio/ChangeLog
+++ b/gio/ChangeLog
@@ -1,3 +1,10 @@
+2008-01-15  Alexander Larsson  <alexl@redhat.com>
+
+        * gmemoryinputstream.c:
+        * gmemoryoutputstream.c:
+	Don't do pointer arithmetic on void * (#508602)
+	Patch from Kazuki IWAMOTO
+
 2008-01-14  Matthias Clasen  <mclasen@redhat.com>
 
 	* === Released 2.15.2 ===
diff --git a/gio/gmemoryinputstream.c b/gio/gmemoryinputstream.c
index c215e2f35..9255efbf6 100644
--- a/gio/gmemoryinputstream.c
+++ b/gio/gmemoryinputstream.c
@@ -283,7 +283,7 @@ g_memory_input_stream_read (GInputStream  *stream,
       chunk = (Chunk *)l->data;
       size = MIN (rest, chunk->len - start);
 
-      memcpy (buffer + (count - rest), chunk->data + start, size);
+      memcpy ((guint8 *)buffer + (count - rest), chunk->data + start, size);
       rest -= size;
 
       start = 0;
diff --git a/gio/gmemoryoutputstream.c b/gio/gmemoryoutputstream.c
index bb3b47842..861342211 100644
--- a/gio/gmemoryoutputstream.c
+++ b/gio/gmemoryoutputstream.c
@@ -313,7 +313,7 @@ array_resize (GMemoryOutputStream  *ostream,
     }
 
   if (size > len)
-    memset (data + len, 0, size - len);
+    memset ((guint8 *)data + len, 0, size - len);
 
   priv->data = data;
   priv->len = size;
@@ -365,7 +365,7 @@ g_memory_output_stream_write (GOutputStream  *stream,
      only added part of the required memory */
   count = MIN (count, priv->len - priv->pos);
   
-  dest = priv->data + priv->pos;
+  dest = (guint8 *)priv->data + priv->pos;
   memcpy (dest, buffer, count); 
   priv->pos += count;