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List:       netbsd-tech-kern
Subject:    Re: changing KASSERT()'s definition for non-diag kernels
From:       Alan Barrett <apb () cequrux ! com>
Date:       2013-10-20 8:28:35
Message-ID: 20131020082835.GH1154 () apb-laptoy ! apb ! alt ! za
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On Sun, 20 Oct 2013, matthew green wrote:
> as part of the GCC 4.8 preparation work, we're seeing many new 
> warnings where variables are only used inside KASSERT(), but the 
> non-diag kernel builds trigger errors.
>
> my solution, rather than marking these variables with __USE(), 
> is to change KASSERT() into a real function that consumes its 
> arguments, but is still an empty function.

That seems sensible to me.  More generally, a lot of our exiting 
macros can be rewritten as static inline functions, now that we 
require a C99 compiler.

> note that there is a re-direction to force the input to 
> KASSERT() to be an integer type, as it is called with all sorts 
> of types of input (pointers, values, boolean expressions..)

The KASSERT macro can be invoked with anything that has a 
truth value as its first argument.  Casting that to int seems 
reasonable, but perhaps using (!!(e)) to convert any type to a 
truth value would be clearer and less likely to trigger compiler 
warnings about casting non-numeric types to int.

--apb (Alan Barrett)
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