This is the mail archive of the gcc@gcc.gnu.org mailing list for the GCC project.

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]

Re: Linux and aliasing?

To: Linus Torvalds <torvalds at transmeta dot com>
Subject: Re: Linux and aliasing?
From: Jamie Lokier <egcs at tantalophile dot demon dot co dot uk>
Date: Mon, 7 Jun 1999 22:34:45 +0200
Cc: mark at codesourcery dot com, rth at cygnus dot com, tim at wagner dot Princeton dot EDU, craig at jcb-sc dot com, davem at redhat dot com, chip at perlsupport dot com, egcs at egcs dot cygnus dot com
References: <19990606174538V.mitchell@codesourcery.com> <Pine.LNX.3.95.990607083858.22237A-100000@penguin.transmeta.com>

Linus Torvalds wrote:
> > I think by now you've been presented with a variety of strategies for
> > solving the problem in the kernel, including more than one idea for
> > macros that you could use like:
> > 
> >   ALIASING_CAST (type, x)
> 
> I've been told in private email, that the proposed macro wasn't even
> standards conforming in the sense that it doesn't guarantee that the
> compiler couldn't decide it aliases (because in order to guarantee that
> the union should contain all possible types). It happens to work for gcc.

Luckily, GCC has __typeof__.
So you can just put the target type and __typeof__(x) in the union --
should work shouldn't it?

-- Jamie

References:
- Re: Linux and aliasing?
  - From: mark
- Re: Linux and aliasing?
  - From: Linus Torvalds

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]