Re: [PATCH] ARC: build: Turn off -Wmaybe-uninitialized for ARC gcc 4.8
From: Vineet Gupta
Date: Fri Mar 18 2016 - 06:43:57 EST
On Friday 18 March 2016 03:59 PM, Arnd Bergmann wrote:
> On Friday 18 March 2016 15:50:11 Vineet Gupta wrote:
>> Sure, but I prefer this to be only for gcc 4.8 as this warning seems to be
>> healthy in small doses At least it keeps the door open for future discussion
>> with gcc guys !
>
> FWIW, testing on ARM with gcc-6.0 -O3, I also get tons of maybe-uninitialized
> warnings. It's unlikely that this is architecture specific or fixed in newer
> compiler versions.
So we disable this for good just like -Os.
What a shame - seemed like a reasonable safety net for programming errors.
>> The following nested construct actually works - does that look OK to you ?
>>
>> ARCH_CFLAGS += -O3 $(call cc-ifversion, -lt, 0408, $(call cc-disable-warning,maybe-uninitialized,))
>
> Yes, that seems ok.
There was typo actually -lt needed to be -eq
> I don't really understand why -O3 is needed though, maybe it's better to
> assume that it won't be needed in future gcc versions and do
Not sure what you mean, -O3 for triggering the warnings or -O3 in ARC makefile at all.
Assuming it's latter, this is how its been forever and was added consciously as
performance seemed better with -O3 than the default -O2.
>
> ARCH_CFLAGS += $(call cc-ifversion, -lt, 0408, -O3 $(call cc-disable-warning,maybe-uninitialized,))
>
> Arnd
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>