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Date: Mon, 14 Apr 2025 17:33:26 -0700
From: Nathan Chancellor <nathan@kernel.org>
To: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>,
	Jiri Kosina <jikos@kernel.org>,
	Benjamin Tissoires <bentiss@kernel.org>,
	linux-input@vger.kernel.org, linux-kernel@vger.kernel.org,
	llvm@lists.linux.dev
Subject: Re: [PATCH] HID: simplify code in fetch_item()
Message-ID: <20250415003326.GA4164044@ax162>
References: <ZvwYbESMZ667QZqY@google.com>
 <20241010222451.GA3571761@thelio-3990X>
 <Z_yrjPBO_CPS8WX1@black.fi.intel.com>
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In-Reply-To: <Z_yrjPBO_CPS8WX1@black.fi.intel.com>

On Mon, Apr 14, 2025 at 09:30:36AM +0300, Andy Shevchenko wrote:
> On Thu, Oct 10, 2024 at 03:24:51PM -0700, Nathan Chancellor wrote:
> > On Tue, Oct 01, 2024 at 08:42:36AM -0700, Dmitry Torokhov wrote:
> 
> ...
> 
> > Getting rid of the unreachable() in some way resolves the issue. I
> > tested using BUG() in lieu of unreachable() like the second change I
> > mentioned above, which resolves the issue cleanly, as the default case
> > clearly cannot happen. ...
> 
> As Dmitry pointed out to this old discussion, I have a question about the above
> test. Have you tried to use BUG() while CONFIG_BUG=n? Does it _also_ solve the
> issue?

Yes because x86 appears to always emit ud2 for BUG() regardless of
whether CONFIG_BUG is set or not since HAVE_ARCH_BUG is always
respected.

Cheers,
Nathan