HEADSUP usb2/usb4bsd to become default in GENERIC
Christoph Mallon
christoph.mallon at gmx.de
Mon Feb 23 22:09:23 PST 2009
Hans Petter Selasky schrieb:
> On Monday 09 February 2009, Christoph Mallon wrote:
>> Hans Petter Selasky schrieb:
>>> On Monday 09 February 2009, Christoph Mallon wrote:
>>>> Hans Petter Selasky schrieb:
>>>>> On Monday 09 February 2009, Christoph Mallon wrote:
>>>>>> Christoph Mallon schrieb:
>>>>>>> are named "err" or "error". This should be investigated, so here's
>>>>>>> the complete list:
>>>>>> Sorry, my MUA seems to have damaged the list. You can get the list
>>>>>> here: http://tron.homeunix.org/usb2.unread.log
>>>>> I think some of these errors depend if you have USB debugging compiled
>>>>> or not. At least GCC does not warn?
>>>> No, it does not depend on USB debugging.
>>>> GCC has no warning at all for variables which are only assigned to.
>>>> It only can warn about variables, which are only initialised.
>>>>
>>>> {
>>>> int x = 23; // GCC warns here ...
>>>> int y; // ... but not here - cparser does
>>>> y = 42;
>>>> y++;
>>>> }
>>>>
>>>> cparser has an analysis, which can warn about "y", too.
>>>>
>>>> I manually verified all 40 warnings and I cannot find any users (i.e.
>>>> readers) for these variables.
>>> What is the correct way to discard the return argument of a function?
>>> That's basically what most of the warnings are about.
>>>
>>> 1) (void)my_fn() cast
>>> 2) if (my_fn()) { }
>>> 3) err = my_fn();
>>> 4) my_fn();
>> Just to understand this correctly: You want to discard error codes?
>>
>>
>> Basically I see four categories:
>>
>> 1) Getting the softc and not using it.
>> This can be removed completely.
>> Example:
>> sc = ATMEGA_BUS2SC(xfer->xroot->bus);
>>
>> 2) calling mtx_owned() and discarding the return value.
>> Can be removed, too, after checking that the value is really unnecessary.
>> Example:
>> use_polling = mtx_owned(xfer->xroot->xfer_mtx) ? 1 : 0;
>>
>> 3) Getting some value and not using it.
>> Can be removed, too, after checking that the value is really unnecessary.
>> Example:
>> ep_no = (xfer->endpoint & UE_ADDR);
>>
>> 4) The rest are return values of functions, which contain error codes.
>> Discarding them is questionable at best.
>> Example: (err is not read)
>> if (udev->flags.suspended) {
>> err = DEVICE_SUSPEND(iface->subdev);
>> device_printf(iface->subdev, "Suspend failed\n");
>> }
>> return (0); /* success */
>
> Hi,
>
> Can you wait some days and re-run the analysis on -current, because there is a
> bulk of patches going in to some of the code you have analysed, so the line
> numbers are likely to not match. Then we fix those warnings!
Here's the updated list:
http://tron.homeunix.org/usb2.unread.20090224.log
It contains 33 items. 12 of the variables are named "err" or "error".
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