[PATCH 6/6] [POWERPC] make struct property's value a void *

Paul Mackerras paulus at samba.org
Tue Apr 10 04:20:22 EST 2007

Segher Boessenkool writes:

> Pointers never alias anything.  It's the data accesses
> that matter.  You cannot access one type as another type
> and expect it to work (unless one of those types is a
> character type); that's the one simple rule.

This is true according to the standard (as I understand it), and also
a classic example of the C standards committee stuffing up the C
language by trying to turn it into a "high-level" language.  From the
earliest days of C on the PDP-11 it was understood that memory was an
array of bytes which could be addressed and interpreted in any way the
programmer chose.  For systems programming tasks that is a very useful
facility, and one which the kernel code generally assumes.  It's a
pity IMHO that the committee chose to throw that away (and yes I
understand that throwing it away makes more optimization opportunities


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