__verify_pcpu_ptr() will cause a compilation failure if the type of the pointer is a pointer to a fixed array of objects. Adding zero to the pointer converts the type of pointer to that pointing to a single object of the array. Signed-off-by: Christoph Lameter <cl@xxxxxxxxx> Index: linux/include/linux/percpu-defs.h =================================================================== --- linux.orig/include/linux/percpu-defs.h 2013-08-22 13:39:04.000000000 -0500 +++ linux/include/linux/percpu-defs.h 2013-08-22 13:41:15.333140537 -0500 @@ -22,9 +22,12 @@ * Macro which verifies @ptr is a percpu pointer without evaluating * @ptr. This is to be used in percpu accessors to verify that the * input parameter is a percpu pointer. + * + * + 0 is required in order to convert the pointer type from a + * potential array type to a pointer to a single item of the array. */ #define __verify_pcpu_ptr(ptr) do { \ - const void __percpu *__vpp_verify = (typeof(ptr))NULL; \ + const void __percpu *__vpp_verify = (typeof((ptr) + 0))NULL; \ (void)__vpp_verify; \ } while (0) -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html