diff --git a/shared-core/r300_cmdbuf.c b/shared-core/r300_cmdbuf.c
index c65ffd5..2db8234 100644
--- a/shared-core/r300_cmdbuf.c
+++ b/shared-core/r300_cmdbuf.c
@@ -253,8 +253,8 @@ static __inline__ int r300_check_offset(drm_radeon_private_t *dev_priv,
 	   but this value is not being kept.
 	   This code is correct for now (does the same thing as the
 	   code that sets MC_FB_LOCATION) in radeon_cp.c */
-	if (offset >= dev_priv->fb_location &&
-	    offset < (dev_priv->fb_location + dev_priv->fb_size))
+	if ((long unsigned int)offset >= (long unsigned int)dev_priv->fb_location &&
+	    (long unsigned int)offset < ((long unsigned int)dev_priv->fb_location + (long unsigned int)dev_priv->fb_size))
 		return 0;
 	if (offset >= dev_priv->gart_vm_start &&
 	    offset < (dev_priv->gart_vm_start + dev_priv->gart_size))