diff --git a/Xext/xres.c b/Xext/xres.c
index 96d5eba7c..a8c9cd01a 100644
--- a/Xext/xres.c
+++ b/Xext/xres.c
@@ -490,12 +490,14 @@ ConstructClientIdValue(ClientPtr sendClient, ClientPtr client, CARD32 mask,
         if (pid != -1) {
             void *ptr = AddFragment(&ctx->response,
                                     sizeof(rep) + sizeof(CARD32));
-            CARD32 *value = (void*) ((char*) ptr + sizeof(rep));
+            CARD32 *value;
 
             if (!ptr) {
                 return FALSE;
             }
 
+            value = (void*) ((char*) ptr + sizeof(rep));
+
             rep.spec.mask = X_XResLocalClientPIDMask;
             rep.length = 4;