RE: [greybus-dev] [PATCH] staging: greybus: fixed the coding style, labels should not be indented.

From: David Laight <David.Laight@ACULAB.COM>
To: 'Alex Elder' <elder@linaro.org>,
	'Manikishan Ghantasala' <manikishanghantasala@gmail.com>,
	Alex Elder <elder@ieee.org>
Cc: Alex Elder <elder@kernel.org>,
	"greybus-dev@lists.linaro.org" <greybus-dev@lists.linaro.org>,
	"linux-staging@lists.linux.dev" <linux-staging@lists.linux.dev>,
	Johan Hovold <johan@kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [greybus-dev] [PATCH] staging: greybus: fixed the coding style, labels should not be indented.
Date: Fri, 4 Jun 2021 08:13:57 +0000	[thread overview]
Message-ID: <c29b5c97f97b48c894917647915bf510@AcuMS.aculab.com> (raw)
In-Reply-To: <10ad30e2-c906-b210-bf0e-5e20b6de1993@linaro.org>

From: Alex Elder
> Sent: 03 June 2021 22:55
...
> Not necessarily, sizeof(bool) is implementation defined.
> And I thought you didn't think the size of the structure
> was very important...

It is 'implementation defined' but will be 32 bits on everything
except an old 32bit ARM ABI.

> In any case, I'm open to changing the type of these fields,
> and my preference would be bool rather than u8, because it
> is completely clear what it represents.

Yes, and it isn't at all clear what it actually means.
If the value of a bool memory location isn't 0 or 1
what does 'bool_a & bool_b' mean.
It might be 'undefined behaviour' - but that doesn't actually
exclude an ICBM hitting the coder's house!
I've seen very silly code generated (by an old gcc) for
simple statements like:
	bool_a |= bool_b;
Mostly because it didn't trust the values to be 0 or 1
and wanted to ensure the result was either 0 or 1.

If I use an integer type (as in traditional C) I know
what I'm getting and there are no unexpected comparisons
and conditionals.

	David

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