Re: Subject: [RFC] clang tooling cleanups

[Nick Desaulniers]

On Tue, Oct 27, 2020 at 12:52 PM Joe Perches <joe@xxxxxxxxxxx> wrote:
>
> (Adding Stephen Rothwell)
>
> On Tue, 2020-10-27 at 12:33 -0700, Tom Rix wrote:
> > On 10/27/20 11:42 AM, Nick Desaulniers wrote:
> > > (cutting down the CC list to something more intimate)
>
> []
>
> > I am interested in treewide fixes.
>
> As am I, but here the definition of fixes is undefined though.
> Whitespace / style changes and other bits that don't change generated
> object code aren't considered fixes by many maintainers.
>
> > Cleaning them up (maybe me not doing all the patches) and keeping them clean.
> >
> > The clang -Wextra-semi-stmt -fixit will fix all 10,000 problems
>
> I rather doubt there are 10K extra semicolons in the kernel source tree.
> Is there a proposed diff/patch posted somewhere?

Ah, I think I see where I (and Joe) may be misinterpreting.  Tom, do
you mean to say that `clang -fixit` will attempt to fix EVERY warning
in tree (including but regardless of -Wextra-semi-stmt, where
-Wextra-semi-stmt is a red herring), so the clang-tidy check is
specific to applying fixits just for -Wextra-semi-stmt?  (If so, I
wonder if we could improve clang to accept more fine grain control
over *which* fixits we want applied.  Not at all of them for all of
the different distinct warnings, for example).

>
> > This clang tidy fixer will fix only the 100 problems that are 'switch() {};'
> >
> > When doing a treewide cleanup, batching a bunch of fixes that are the same problem and fix
> > is much easier on everyone to review and more likely to be accepted.
>
> That depends on the definition of batching.
>
> If individual patches are sent to multiple maintainers, the
> acceptance / apply rate seems always < 50% and some are rejected
> outright by various maintainers as "unnecessary churn".
>
> Single treewide patches are generally not applied unless by Linus.
> The trivial tree isn't widely used for this.
>
> Perhaps a 'scripted' git tree could be established that is integrated
> into -next that would allow these automated patches to be better
> vetted and increase the acceptance rate of these automated patches.
>
> > Long term, a c/i system would keep the tree clean by running the switch-semi checker/fixer.
> > And we can all move onto the next problem.
>
> Good idea...
> I hope a scripted patches mechanism will be established.

Yes, if I can automate myself out of job, then I can hang out of the
roof and drink margaritas all day.  That is the plan of record, but
this !##$'ing compiler is constantly broken!!!!1

-- 
Thanks,
~Nick Desaulniers