Re: [PATCH v2] compiler: prevent dead store elimination

[Andi Kleen]

>  > +	do {						\
>  > +		struct __scrub { typeof(*p) c[n]; };	\
> 
> The typeof(*p) suggestion doesn't work. It would require p to always be
> a pointer type with an accurate (for memset) sizeof(*p). In general however
> we'll memset some array described by a void*/size_t pair, and typeof in
> that case is useless. The original'struct __scrub { char c[n]; };' was Ok.

I just suggested it because of the original array name of the macro
and without it it would have only worked for char arrays. With the new
naming it's ok I guess.

It could be made to work with macros and builtin_type_match I guess,
but it would be fairly ugly and not worth it.

-Andi

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