On 02/09/2016 07:26 AM, Arnd Bergmann wrote:
On Tuesday 09 February 2016 07:08:59 Guenter Roeck wrote:IS_ERR_VALUE() assumes that its parameter is an unsigned long. It can not be used to check if an unsigned int reflects an error. Doing so can result in the following build warning. drivers/tty/serial/digicolor-usart.c: In function ‘digicolor_uart_probe’: include/linux/err.h:21:38: warning: comparison is always false due to limited range of data type drivers/tty/serial/digicolor-usart.c:485:6: note: in expansion of macro ‘IS_ERR_VALUE’ If that warning is seen, an error return from platform_get_irq() is missed.The patch looks correct to me, but what compiler version and which kernel tree is it that triggered the warning? Andrzej Hajda just modified the definition of IS_ERR_VALUE(), and the changes are still under discussion, but I don't see that warning with any of the versions.
I see it with gcc 5.1 and 5.2 (and W=1). I did not see / notice Andrzej's patch. I agree that fixing the problem in IS_ERR_VALUE() is preferrable. Guenter -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
