2015-01-29 3:37 GMT+01:00 Chris Rorvick <chris@xxxxxxxxxxx>: > On Wed, Jan 28, 2015 at 4:42 PM, Rickard Strandqvist > <rickard_strandqvist@xxxxxxxxxxxxxxxxxx> wrote: >> Variable ar assigned a value that is never used. >> I have also removed all the code that thereby serves no purpose. > > Each of these changes adds a warning ... > >> diff --git a/drivers/staging/emxx_udc/emxx_udc.c b/drivers/staging/emxx_udc/emxx_udc.c >> index eb178fc..b916fab 100644 >> --- a/drivers/staging/emxx_udc/emxx_udc.c >> +++ b/drivers/staging/emxx_udc/emxx_udc.c >> @@ -2974,10 +2974,10 @@ static int nbu2ss_ep_fifo_status(struct usb_ep *_ep) >> spin_lock_irqsave(&udc->lock, flags); >> >> if (ep->epnum == 0) { >> - data = _nbu2ss_readl(&preg->EP0_LENGTH) & EP0_LDATA; >> + _nbu2ss_readl(&preg->EP0_LENGTH) & EP0_LDATA; > > .../linux/drivers/staging/emxx_udc/emxx_udc.c:2977:36: warning: value > computed is not used [-Wunused-value] > _nbu2ss_readl(&preg->EP0_LENGTH) & EP0_LDATA; > ^ > >> } else { >> - data = _nbu2ss_readl(&preg->EP_REGS[ep->epnum-1].EP_LEN_DCNT) >> + _nbu2ss_readl(&preg->EP_REGS[ep->epnum-1].EP_LEN_DCNT) >> & EPn_LDATA; > > .../linux/drivers/staging/emxx_udc/emxx_udc.c:2981:4: warning: value > computed is not used [-Wunused-value] > & EPn_LDATA; > ^ > >> } >> >> @@ -3264,12 +3264,11 @@ static void __init nbu2ss_drv_set_ep_info( >> if (isdigit(name[2])) { >> >> long num; >> - int res; >> char tempbuf[2]; >> >> tempbuf[0] = name[2]; >> tempbuf[1] = '\0'; >> - res = kstrtol(tempbuf, 16, &num); >> + kstrtol(tempbuf, 16, &num); > > .../linux/drivers/staging/emxx_udc/emxx_udc.c:3271:3: warning: > ignoring return value of ‘kstrtol’, declared with attribute > warn_unused_result [-Wunused-result] > kstrtol(tempbuf, 16, &num); > ^ Hi The first two were my fault, stupid of me to let the "& number" remain :( The last one was more interesting, se below. But I can not really see how any error should be handled here? Proposal to change to: if (kstrtol(tempbuf, 16, &num) == 0 && num == 0) static inline int __must_check kstrtol(const char *s, unsigned int base, long *res); "The __must_check annotation makes use of the gcc warn_unused_result attribute; it first found its way into the mainline in 2.6.8. If a function is marked __must_check, the compiler will issue a strong warning whenever the function is called and its return code is unused. " Kind regards Rickard Strandqvist _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel