diff --git a/xen/include/public/version.h b/xen/include/public/version.h
index 9c78b4f3b6..0ff8bd9077 100644
--- a/xen/include/public/version.h
+++ b/xen/include/public/version.h
@@ -50,7 +50,7 @@ typedef struct xen_platform_parameters xen_platform_parameters_t;
 
 #define XENVER_get_features 6
 struct xen_feature_info {
-    unsigned int submap_idx;    /* IN: which 32-bit submap to return */
+    uint32_t     submap_idx;    /* IN: which 32-bit submap to return */
     uint32_t     submap;        /* OUT: 32-bit submap */
 };
 typedef struct xen_feature_info xen_feature_info_t;