Re: linux-next: build warning after merge of the tip tree

Thomas Gleixner
2020-04-01T10:25:37Z

Stephen Rothwell <sfr@canb.auug.org.au> writes:
> Hi all,
>
> On Mon, 30 Mar 2020 13:47:46 +1100 Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>>
>> Hi all,
>>
>> After merging the tip tree, today's linux-next build (arm
>> multi_v7_defconfig) produced this warning:
>>
>> kernel/futex.c: In function 'do_futex':
>> kernel/futex.c:1676:17: warning: 'oldval' may be used uninitialized in this function [-Wmaybe-uninitialized]
>> 1676 | return oldval == cmparg;
>> | ~~~~~~~^~~~~~~~~
>> kernel/futex.c:1652:6: note: 'oldval' was declared here
>> 1652 | int oldval, ret;
>> | ^~~~~~
>>
>> Introduced by commit
>>
>> a08971e9488d ("futex: arch_futex_atomic_op_inuser() calling
>> conventions change")

Huch?

>> but I don't see how it makes this difference :-(

Me neither. Which compiler version?

I'm using arm-linux-gnueabi-gcc (Debian 8.3.0-2) 8.3.0 which does not
show that oddity.

Thanks,

tglx