---------- Forwarded message ---------- From: Andy Shevchenko <andy.shevchenko@xxxxxxxxx> Date: Thu, Feb 11, 2016 at 10:10 AM Subject: Re: [PATCH 2/3] usb: type-c: USB Type-C Connector System Software Interface To: Oliver Neukum <oneukum@xxxxxxx> On Wed, Feb 10, 2016 at 5:08 PM, Oliver Neukum <oneukum@xxxxxxx> wrote: > On Wed, 2016-02-10 at 16:24 +0200, Andy Shevchenko wrote: >> On Wed, Feb 10, 2016 at 4:15 PM, Oliver Neukum <oneukum@xxxxxxxx> wrote: >> > On Wed, 2016-02-10 at 13:56 +0200, Andy Shevchenko wrote: >> >> > +err: >> >> > + if (i > 0) >> >> > + for (; i >= 0; i--, con--) >> >> > + typec_unregister_port(con->port); >> >> >> >> Perhaps >> >> >> >> while (--i >= 0) { >> >> ... >> >> } >> > >> > While we are at it. No we should not change the semantics >> > of conditionals for the sake of appearance. >> >> I'm sorry I didn't get you. >> How this more or less standard pattern to clean up stuff on error path >> does with conditional semantics? > > You change a postdecrement to a predecrement. The highest > number the loop is executed for is changed. I still didn't get. Variable i is just counter here, And it seems there is a bug, since when i == 1, we will have i = 1, con == connector[0]: typec_unregister_port(con->port); i = 0, con == connector[1]: typec_unregister_port(con->port); <<< It wasn't registered yet! The correct code should be something like if (i > 0) for (--i; i >= 0; i--) {} Which a) makes conditional redundant; b) classical pattern of while (--i >= 0) {} So where am I wrong? -- With Best Regards, Andy Shevchenko -- With Best Regards, Andy Shevchenko -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html