Re: [RFC/PATCH] doc: volatile considered evil

[Jeremy Fitzhardinge]

David Rientjes wrote:
> It is analogous with a sequence point for ia64.  But, as you mentioned, it 
> is ia64 specific so your comment about "asm volatile" constructs not being 
> reordered is always appropriate outside of ia64 specific code but may not 
> apply to ia64 if we ever compiled with -mvolatile-asm-stop.  If we do not
> compile with that option, the behavior is unspecified.  I don't think 
> we'll be adding -mvolatile-asm-stop support any time soon so your warning 
> certainly is appropriate for all code at this time.
>   

Sounds like it's referring to micro-architectural reordering, which is
distinct from compiler reordering.  In other words, even if you
specified "-mvolatile-asm-stop" I would assume that the compiler could
still reorder the asm statements.  Am I right, or should I read more
into the manual description than it actually says?

    J
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