Re: [PATCH] 2.4.21-rc1: byteorder.h breaks with __STRICT_ANSI__ defined (trivial)

[Daniel Jacobowitz <dan@debian.org>]

On Thu, Nov 06, 2003 at 12:05:48PM -0800, David S. Miller wrote:
> On Thu, 06 Nov 2003 22:09:29 +0200
> Martin Schlemmer <azarah@gentoo.org> wrote:
> 
> > On Thu, 2003-11-06 at 21:37, David S. Miller wrote:
> > > Let's say that you end up using some inline function
> > > that takes u32 arguments, and internally it uses
> > > u64 types to speed up the calculation or make it more
> > > accurate or something like that.
> > 
> > So basically only in cases where the stuff in byteorder.h
> > was not inlined ... ?
> 
> No, exactly in the cases where it _IS_ inlined.  Imagine
> this:
> 
> static inline u32 swab_foo(u32 a, u32 b)
> {
> 	u64 tmp = ((u64)a<<32) | ((u64)b);
> 	u32 retval;
> 
> 	retval = compute(tmp);
> 
> 	return retval;
> }
> 
> If that's in a kernel header somewhere, and you build with -ansi,
> you lose.

In general the inlines should be __KERNEL__'d anyway.  In any case, the
prior art in <linux/types.h> is:

#if defined(__GNUC__) && !defined(__STRICT_ANSI__)
typedef         __u64           uint64_t;
typedef         __u64           u_int64_t;
typedef         __s64           int64_t;
#endif

Or did I miss something at the beginning of this conversation?


[Debian is already using similar patches, which disable the 64-bit
swabbing in __STRICT_ANSI__.]

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer