cvs commit: src/sys/vm vm_map.c

[Bruce Evans]

On Tue, 29 Jun 2004, David Schultz wrote:

> On Wed, Jun 30, 2004, Bruce Evans wrote:
> > On Tue, 29 Jun 2004, Andrew Gallatin wrote:
> >
> > > Bruce Evans writes:
> > >  > MIN() and MAX() should not be used in the kernel.  4.4BSD removed them in
> > >  > the kernel, but FreeBSD broke this in rev.1.141 of sys/param.h.  They
> > >  > remain removed in RELENG_4.
> > >
> > > OK.  Then what's the correct fix? ulmin()?
> >
> > Fixing min() to handle all unsigned types is probably best.
>
> Hmm...but this means either
>
> a) slightly pessimizing 32-bit ports with a function on uintmax_t's,

This was in my list of slightly incorrect fixes.

> b) using a macro and introducing double-expansion problems, or

This was removed in 4.4BSD.

> c) using GCC extensions
>
> Option (c) seems best from a technical standpoint, except that
> we'd be making it harder than it already is to compile the kernel
> with compilers other than gcc and icc.  (Do others have the
> statement expr extension?)

I tried not to use gcc extensions for this back in FreeBSD-2, but
the kernel is now so full with gccisms that another one wouldn't
matter.  It needs __typeof() more than staement-expressions.

Bruce