Linux SPARSE checker discussions
 help / color / mirror / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>,
	linux-sparse@vger.kernel.org, Christopher Li <sparse@chrisli.org>,
	kbuild test robot <fengguang.wu@intel.com>,
	kbuild-all@01.org, LKML <linux-kernel@vger.kernel.org>,
	tipbuild@zytor.com, Ingo Molnar <mingo@kernel.org>
Subject: Re: [tip:locking/core 9/11] include/asm-generic/atomic-instrumented.h:288:24: sparse: cast truncates bits from constant value (100 becomes 0)
Date: Tue, 13 Mar 2018 19:08:06 +0100	[thread overview]
Message-ID: <20180313180806.GO4043@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20180313180016.5axdobx6a624snpp@ltop.local>

On Tue, Mar 13, 2018 at 07:00:17PM +0100, Luc Van Oostenryck wrote:
> The issue here is that sparse has a whole class of warnings that are
> given very early (here at expansion of constant expressions), before
> eliminating code from branches that are never taken (which, surprise,
> need itself to have constant expressions already expanded).
> 
> It's often annoying like the case here.
> OTOH, I don't think it's always a bad thing. Sometimes we want to
> have warnings even from code we know will not be executed (in this
> config but maybe it will in another one).

Is that really a valid concern with all the automated randconfig
building going on today?

  reply	other threads:[~2018-03-13 18:08 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <201803122219.vHl3IwRo%fengguang.wu@intel.com>
     [not found] ` <CACT4Y+Yscqe6M1jXSkcuvw+5-27YzZn4AXwKzU1oJCNhUrj1Ng@mail.gmail.com>
     [not found]   ` <CACT4Y+ayA+maaG3uddxpy3w24Jyppsxmyu5R_rEsvm3JjtZkRQ@mail.gmail.com>
     [not found]     ` <20180313104652.GK4043@hirez.programming.kicks-ass.net>
2018-03-13 11:08       ` [tip:locking/core 9/11] include/asm-generic/atomic-instrumented.h:288:24: sparse: cast truncates bits from constant value (100 becomes 0) Dmitry Vyukov
2018-03-13 17:29         ` Christopher Li
2018-03-13 18:00         ` Luc Van Oostenryck
2018-03-13 18:08           ` Peter Zijlstra [this message]
2018-03-13 20:01             ` Luc Van Oostenryck

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180313180806.GO4043@hirez.programming.kicks-ass.net \
    --to=peterz@infradead.org \
    --cc=dvyukov@google.com \
    --cc=fengguang.wu@intel.com \
    --cc=kbuild-all@01.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-sparse@vger.kernel.org \
    --cc=luc.vanoostenryck@gmail.com \
    --cc=mingo@kernel.org \
    --cc=sparse@chrisli.org \
    --cc=tipbuild@zytor.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox