Re: GCC 3.4 Heads-up

[Linus Torvalds]

On Fri, 26 Dec 2003, Andy Isaacson wrote:
> 
> But doesn't the first one potentially let the compiler avoid spilling to
> memory, if b and c are both in registers?

Sure, and you can do it as

	tmp = d;
	a ? b = tmp : c = tmp;

instead if you want to. It all depends on what b/c actually are (ie maybe
they are memory-backed anyway).

The point being that there are no actual _advantages_ to being
non-standard. And there are definitely disadvantages. Lack of portability
being one, semantic confusion being another (the semantic confusion is
more visible in C++, since there lvalue'ness is more complex. But it's
visible in C too, where the gcc extensions can cause buggy programs that
_should_ give syntax errors to possibly compile to unexpected results).

		Linus
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