Re: [PATCH] "volatile considered harmful", take 3

[H. Peter Anvin]

H. Peter Anvin wrote:
> 
> I don't see why Alan's way is necessarily better; it should work but is
> more heavy-handed as it's disabling *all* optimization such as loop
> invariants across the barrier.
> 

To expand on this further: the way this probably *should* be handled,
Linux-style, is with internally-volatile versions of le32_to_cpup() and
friends.  That obeys the concept that the volatility should be
associated with an operation, not a data structure, and, being related
to an I/O device, should have its endianness explicitly declared.

Right now those macros don't exist, however.

	-hpa
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