Re: [PATCH] tools/perf: Do not set a variable unless it will be used

[Peter Zijlstra]

On Fri, Jun 04, 2021 at 09:24:23PM +0200, Ricardo Ribalda wrote:
> Hi Peter
> 
> On Fri, 4 Jun 2021 at 11:36, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> >
> > On Fri, Jun 04, 2021 at 11:26:38AM +0200, Ricardo Ribalda wrote:
> > > clang-13 triggers the following warning:
> > >
> > > bench/inject-buildid.c:351:6: error: variable 'len' set but not used [-Werror,-Wunused-but-set-variable]
                                                                         clue here: ^^^^^^^^^^^^^

> > >         u64 len = 0;
> > >
> > > This patch sets the value to len only if it will be used afterwards.
> >
> > My vote would be to kill that warning, what absolute shite.
> 
> My knowledge of llvm codebase is close to NULL, so it is much easier
> for me to "fix" the code.

That's what -Wno-unused-but-set-variable is for, which is trivial to add
to the Makefile.