[PATCH 02/18] arm64: move SCTLR_EL{1,2} assertions to <asm/sysreg.h>

Mark Rutland mark.rutland at arm.com
Mon May 14 06:10:13 PDT 2018


On Mon, May 14, 2018 at 01:41:23PM +0100, Dave Martin wrote:
> On Mon, May 14, 2018 at 01:06:10PM +0100, Mark Rutland wrote:
> > On Mon, May 14, 2018 at 12:56:09PM +0100, Robin Murphy wrote:
> > > On 14/05/18 12:20, Dave Martin wrote:
> > > > How about the following?
> > > > 
> > > > /* Watch out for #if evaluation rules: ~0 is not ~(int)0! */
> > > 
> > > Or, more formally, perhaps something even less vague like "Note that in
> > > preprocessor arithmetic these constants are effectively of type intmax_t,
> > > which is 64-bit, thus ~0 is not what we want."
> > 
> > I'll drop something in the commit message to that effect, rather than a
> > comment.
> > 
> > A comment will end up terse and vague or large and bloatsome (and
> > redundant as we have this pattern twice).
> > 
> > Anyone attempting to "clean" this up will find things break, and they can
> > look at the git log to find out why it is the way it is...
> 
> Fair enough.  So long as we say something somewhere, that's
> sufficient for me.
> 
> With that,
> 
> Reviewed-by: Dave Martin <Dave.Martin at arm.com>
> 
> (as previously stated).

Cheers!

Mark.



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