[U-Boot] [RFC PATCH] USB: get rid of warning when compile with debug enabled

Marek Vasut
2014-08-26T06:46:59Z

On Tuesday, August 26, 2014 at 03:11:13 AM, Bo Shen wrote:
> Hi Marek,
>
> On 08/25/2014 06:43 PM, Marek Vasut wrote:
> > On Monday, August 25, 2014 at 11:23:19 AM, Bo Shen wrote:
> >> When compile with debug information is enabled, if call
> >> spin_lock_irqsave, it will give following warning information.
> >> This patch is used to get rid of it.
> >> --->8---
> >> warning: 'flags' is used uninitialized in this function
> >> [-Wuninitialized] ---8<---
> >
> > The patch is wrong. The compiler complains that flags might be used
> > uninited because that is the case -- you call spin_lock_irqsave() with
> > uninited flags and because debug() is expanded to printf() I guess, the
> > compiler spews.
> >
> > So which file does this warning come from ?
>
> I enable debug information (In common.h, define the DEBUG).
>
> It comes out from usb gadget driver, for example, atmel_usba_udc.c and
> also s3c_udc_otg.c and etc.

Then those need fixing. There is no problem with the macro.

> I see the spin_lock_irqsave() function in
> <drivers/usb/musb-new/linux-compat.h> defined as:
> --->8---
> #define spin_lock_irqsave(lock, flags) do {} while (0)
> ---8<---
>
> As in u-boot, there is no lock actually, so I think we can fix it as
> <drivers/usb/musb-new/linux-compat.h>, or use the patch as I suggest, or
> anything else, what about your opinion?

Fix all the offending drivers which pass uninited variable into macro which
might use it. That's the fix.

Best regards,
Marek Vasut