3.0.1 Freeze
Mark Mitchell
mark@codesourcery.com
Tue Aug 7 12:53:00 GMT 2001
> #define PTRRELOC(x) ((typeof(x))((unsigned long)(x) + offset))
> #define RELOC(x) (*PTRRELOC(&(x)))
> offset = get_reloc_offfset();
> strcpy(dest, RELOC("test"));
>
> I don't see anything illegal/undefined/unportable about that code, just
> plain C pointer arithmetic to implement a poor mans relocation in early
> boot code.
Ah. So, ignoring the non-standard `typeof', you have cast a pointer to
an integer, added another integer, and cast back to a pointer. That
is (I checked) implementation-defined behavior, but the sensible
definition is that it do what you think.
So, I am now convinced that this optimization is too aggressive. I
will simply remove it.
Thank you,
--
Mark Mitchell mark@codesourcery.com
CodeSourcery, LLC http://www.codesourcery.com
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