diff --git a/sysdeps/unix/alpha/sysdep.h b/sysdeps/unix/alpha/sysdep.h
index 2260ec5480..2e5bc798eb 100644
--- a/sysdeps/unix/alpha/sysdep.h
+++ b/sysdeps/unix/alpha/sysdep.h
@@ -415,7 +415,7 @@ __LABEL(name)						\
 # else
 extern uintptr_t __pointer_chk_guard_local attribute_relro attribute_hidden;
 #  define PTR_MANGLE(var)	\
-	(var) = (void *) ((uintptr_t) (var) ^ __pointer_chk_guard_local)
+  (var) = (__typeof (var)) ((uintptr_t) (var) ^ __pointer_chk_guard_local)
 #  define PTR_DEMANGLE(var)  PTR_MANGLE(var)
 # endif
 #elif defined PIC