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From: David Howells <dhowells@redhat.com>
In-Reply-To: <20220707182052.769989-1-justinstitt@google.com>
References: <20220707182052.769989-1-justinstitt@google.com> <20220706235648.594609-1-justinstitt@google.com>
To: Justin Stitt <justinstitt@google.com>
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Subject: Re: [PATCH v2] net: rxrpc: fix clang -Wformat warning
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Date: Fri, 08 Jul 2022 10:39:04 +0100
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X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3

Justin Stitt <justinstitt@google.com> wrote:

> y is a u32 but the format specifier is `%hx`. Going from unsigned int to
> short int results in a loss of data. This is surely not intended
> behavior. If it is intended, the warning should be suppressed through
> other means.

Yeah, y is reduced to a 16-bit number so that it can be used in the protocol,
but the type is still 32-bit because that's needed for the calculation.  An
alternative would be to print sp->hdr.cksum since that's the value that will
appear on the wire, but I've no objection to this change either.

> This patch should get us closer to the goal of enabling the -Wformat
> flag for Clang builds.
> 
> Link: https://github.com/ClangBuiltLinux/linux/issues/378
> Signed-off-by: Justin Stitt <justinstitt@google.com>

Acked-by: David Howells <dhowells@redhat.com>