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On Tue, Oct 08, 2024 at 08:50:00AM -0400, Mouse wrote:
> > [...], using the C standard guaranteed property that the address of
> > the first member is the address of the structure, allowing to cast
> > pointers in order to operate whether on the base structure or on the
> > derived structure?
>
> Which standard promises this, and what exactly does it promise? I've
> been looking through C99 and the closest I've found so far is 6.5.2.3
> #5, which is not quite the same:
>
K & R, "The C Programming Language", second edition (english version),
p 213:
The members of a structure have addresses increasing in the
order of their declarations. A non-field member of a structure
is aligned at an addressing boundary depending on its type,
therefore, there may be unnamed holes in a structure. If a
pointer to a structure is cast to the type of a pointer to its
first member, the result refers to the first member.
--
Thierry Laronde <tlaronde +AT+ kergis +dot+ com>
http://www.kergis.com/
http://kertex.kergis.com/
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