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Re: Strict aliasing and pointers to functions
On Sun, 26 Nov 2006, Andrew Haley wrote:
Are we talking ISO C or GNU C here? This is OK for GNU C, and I think
You mentioned ISO C a few times. So i'd guess we are talking c89.
> However i'm not targetting standard C
So why are you using -pedantic? -pedantic is only for strict ISO C.
Because i happen to compile with 5-6 versions of gcc on different
platforms with different ideas of what -W[xxx] turns on and throwing
`-pedantic' into the mix generally turns on more.
* The cast below is the correct way to handle the problem.
* The (void *) cast is to avoid a GCC warning like:
* "warning: dereferencing type-punned pointer will break \
* strict-aliasing rules"
* which is wrong this code. (void *) introduces a compatible
* intermediate type in the cast list.
count -= got, *(char **)(void *)&buffer += size * got;
I'm not convinced this hackery is correct by my reading of ISO C, and
in any case it's pointless. It could be replaced by:
count -= got, buffer = (char*)buffer + (size * got);
That's not for me to decide, not a language layer by any stretch of