Re: casting of structs

From: Peter Pichler (pichlo7_at_pobox.sk)
Date: 12/29/03 

Date: Mon, 29 Dec 2003 21:30:30 -0000

Christopher Benson-Manica wrote :
> Peter Pichler spoke thus:
>
> > No. A pointer to a structure can be portably /converted/ to a pointer to
the
> > first element of the structure and back.
>
> FMI, can you quote the portion of the Standard that allows this?
> Consider my curiousity piqued :)

Ehm, did I manage to make a fool of myself /again/? ;-)

No quote, just my simplified interpretation of 6.7.2.1:
...
13 Within a structure object, the non-bit-field members and the units in
   which bit-fields reside have addresses that increase in the order in
   which they are declared. A pointer to a structure object, suitably
                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   converted, points to its initial member (or if that member is a
bit-field,
   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   then to the unit in which it resides), and vice versa. There may be
                                          ^^^^^^^^^^^^^^
   unnamed padding within a structure object, but not at its beginning.

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