Date: Thu, 9 Jul 2009 04:24:46 +1000 (EST) From: Bruce Evans <brde@optusnet.com.au> To: Rui Paulo <rpaulo@freebsd.org> Cc: svn-src-projects@freebsd.org, src-committers@freebsd.org Subject: Re: svn commit: r195460 - projects/mesh11s/sys/net80211 Message-ID: <20090709041145.G46111@delplex.bde.org> In-Reply-To: <200907081526.n68FQYDb055185@svn.freebsd.org> References: <200907081526.n68FQYDb055185@svn.freebsd.org>
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On Wed, 8 Jul 2009, Rui Paulo wrote:
> Log:
> Remove some spurious __packed attributes.
Are they spurious? All uses of __packed are wrong, but they might still
help work around ABI bugs.
> Modified:
> projects/mesh11s/sys/net80211/ieee80211_mesh.h
>
> Modified: projects/mesh11s/sys/net80211/ieee80211_mesh.h
> ==============================================================================
> --- projects/mesh11s/sys/net80211/ieee80211_mesh.h Wed Jul 8 15:25:27 2009 (r195459)
> +++ projects/mesh11s/sys/net80211/ieee80211_mesh.h Wed Jul 8 15:26:34 2009 (r195460)
> @@ -46,7 +46,7 @@ struct ieee80211_meshconf_ie {
> uint8_t conf_authid[4]; /* Auth. Protocol ID */
> uint8_t conf_form; /* Formation Information */
> uint8_t conf_cap;
> -} __packed;
> +};
Broken ABIs (e.g., arm?) may add padding at the end of structs, so it
doesn't help for all members of a struct to have type uint8_t. I think
arm always pads to make the size a multiple of 4. The natural size of
the above struct is 6, so it seems to need __packed.
Bruce
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