diff --git a/arch/alpha/include/asm/futex.h b/arch/alpha/include/asm/futex.h
index e8a761aee088..f939794363ac 100644
--- a/arch/alpha/include/asm/futex.h
+++ b/arch/alpha/include/asm/futex.h
@@ -108,7 +108,7 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
 	"	lda	$31,3b-2b(%0)\n"
 	"	.previous\n"
 	:	"+r"(ret), "=&r"(prev), "=&r"(cmp)
-	:	"r"(uaddr), "r"((long)oldval), "r"(newval)
+	:	"r"(uaddr), "r"((long)(int)oldval), "r"(newval)
 	:	"memory");
 
 	*uval = prev;