Re: sizeof problem in kernel modules

[Andreas Schwab <schwab@suse.de>]

Alan Shutko <ats@acm.org> writes:

|> Alan Shutko <ats@acm.org> writes:
|> 
|> > You can look at other things too... you can memcpy structures, pass
|> > them into functions, call sizeof, put them in arrays... it _is_ a
|> > physical representation.
|> 
|> One more tidbit: ISO/IEC 9899:1990 3.14
|> 
|>   3.14 object: A region of data storage in the execution environment,
|>     the contents of which can represent values.  Except for
|>     bit-fields, objects are composed of contiguous sequences of one or
|>     more bytes, the number, order and encoding of which are either
|>     explicitely specified or implementation-defined.
|> 
|> This would specifically prohibit separating any part of a structure
|> from the rest.

But only under the as-if rule, that is, if you never take the address of a
structure object the compiler can actually put the parts of it anywhere it
likes, because you couldn't notice the difference.

Andreas.

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