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Date:   Fri, 28 Oct 2022 23:55:29 +0300
From:   Alexey Dobriyan <adobriyan@gmail.com>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     akpm@linux-foundation.org, linux-kernel@vger.kernel.org,
        catalin.marinas@arm.com, will@kernel.org,
        rafael.j.wysocki@intel.com, masahiroy@kernel.org
Subject: Re: [PATCH] kbuild: drop -Wdeclaration-after-statement
Message-ID: <Y1xBwRCHoQtMyPf8@p183>
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 <CAHk-=wiEXm3y7BrFnymC_6icE7seicGyyML+Oxd_BP9t=ztNKg@mail.gmail.com>
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On Fri, Oct 28, 2022 at 01:29:08PM -0700, Linus Torvalds wrote:
> On Fri, Oct 28, 2022 at 1:00 PM Alexey Dobriyan <adobriyan@gmail.com> wrote:
> >
> > Putting declarations in the beginning of the block is an afterfact from
> > single pass compiler era. Compiler would parse all declarations, layout
> > stack frame and proceed to generate code.
> 
> No, putting declarations at the beginning is still kernel syntax.
> 
> Don't declare variables in multiple places. It gets really confusing.

It is not. Somehow millions of programmers manage to find their
variables just fine in C and other programming languages.

> Put all declarations at the top of the block they are contained in.

I tried it the other way after years of LK style. Universe didn't collapse.

> IOW, -Wdeclaration-after-statement does exactly the right thing, and stays.
> 
> This is not about "old compilers", this is about coding rules.
> 
>                 Linus