linux-kernel - Re: char-TPM: Adjustments for ten function implementations

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Message-ID: <1508323753.6806.5.camel@perches.com>
Date:   Wed, 18 Oct 2017 03:49:13 -0700
From:   Joe Perches <joe@...ches.com>
To:     Alexander.Steffen@...ineon.com, julia.lawall@...6.fr
Cc:     elfring@...rs.sourceforge.net, linux-integrity@...r.kernel.org,
        linuxppc-dev@...ts.ozlabs.org,
        James.Bottomley@...senPartnership.com, dan.carpenter@...cle.com,
        jarkko.sakkinen@...ux.intel.com, andriy.shevchenko@...ux.intel.com,
        benh@...nel.crashing.org, clabbe.montjoie@...il.com,
        jgunthorpe@...idianresearch.com, jsnitsel@...hat.com,
        kgold@...ux.vnet.ibm.com, mpe@...erman.id.au,
        nayna@...ux.vnet.ibm.com, paulus@...ba.org, PeterHuewe@....de,
        stefanb@...ux.vnet.ibm.com, linux-kernel@...r.kernel.org,
        kernel-janitors@...r.kernel.org
Subject: Re: char-TPM: Adjustments for ten function implementations

On Wed, 2017-10-18 at 10:44 +0000, Alexander.Steffen@...ineon.com wrote:
> > For instance, nothing about
> > > > 	sizeof(type)
> > > > vs
> > > > 	sizeof(*ptr)
> > > > makes it easier for a human to read the code.
> > > 
> > > If it does not make it easier to read the code for you, then maybe you
> > > should consider that this might not be true for all humans. For me, it
> > > makes it much easier to see at a glance, that code like
> > > ptr=malloc(sizeof(*ptr)) is correct.
> > 
> > I don't think there is a perfect solution.
> 
> Maybe. But for the second variant the correctness is easier to check,

How often should
	ptr = alloc(sizeof(*ptr))
be
	ptr = alloc(sizeof(**ptr))

>  both mentally and programmatically, because there is no need for any context (the type of ptr does not matter).

Context matters.