Re: [PATCH] peak_usb: fix clang build warning
From: Arnd Bergmann
Date: Thu Mar 07 2019 - 10:39:14 EST
On Thu, Mar 7, 2019 at 4:31 PM Nathan Chancellor
> On Thu, Mar 07, 2019 at 11:31:55AM +0100, Arnd Bergmann wrote:
> > Clang points out undefined behavior when building the pcan_usb_pro driver:
> > drivers/net/can/usb/peak_usb/pcan_usb_pro.c:136:15: error: passing an object that undergoes default argument promotion to 'va_start' has undefined behavior [-Werror,-Wvarargs]
> > Changing the function prototype to avoid argument promotion in the
> > varargs call avoids the warning, and should make this well-defined.
> > Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> Link: https://github.com/ClangBuiltLinux/linux/issues/109
> Reviewed-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
> I wonder if the format specifier in the pr_err statement at the end of
> this function should be updated.
I think it's still ok as it is.