Re: [PATCH] pinctrl: Include <linux/bug.h> to prevent compile errors

[Stephen Warren <swarren@wwwdotorg.org>]

On 03/09/2012 01:32 PM, Paul Gortmaker wrote:
> [[PATCH] pinctrl: Include <linux/bug.h> to prevent compile errors] On 09/03/2012 (Fri 13:18) Stephen Warren wrote:
> 
>> Macros in <linux/pinctrl/machine.h> call ARRAY_SIZE(), the definition of
>> which eventually calls BUILD_BUG_ON_ZERO(), which is defined in
>> <linux/bug.h>. Include that so that every .c file using the pinctrl macros
>> doesn't have to do that itself.
> 
> Which C files are failing?  The approach was to be adding it only
> for headers with static inlines which use it, and add it to C files
> that are actually *deploying* the macros.

For me, the files that are failing haven't been committed upstream yet;
I expect them to be very soon after the 3.4 merge window completes.

However, I expect you'll see this issue with arch/arm/mach-u300/core.c,
since it uses the same macros defined in pinctrl/machine.h that cause
the problem for me, unless one of the include files there picks up bug.h
already.

As a general statement though, once pinctrl becomes more widely adopted,
I expect to see many files start to use macros from pinctrl/machine.h,
and hence implicitly use ARRAY_SIZE(), and hence even more implicitly
depend on linux/bug.h. I don't think it's at all reasonable to force the
author of every one of those files to track down 3 or 4 levels of header
file dependencies to find that they need linux/bug.h even though they
make no direct use of its features, when it's known that almost any user
of pinctrl/machine.h is going to hit this issue.