Re: + shut-up-warnings-in-ipc-shmc.patch added to -mm tree

[Hugh Dickins <hugh@veritas.com>]

On Thu, 24 Nov 2005, Russell King wrote:
> On Thu, Nov 24, 2005 at 08:00:12AM -0800, Matt Mackall wrote:
> 
> It seems that ({0;}) is used when something is expected to return zero.
> However, if it is used in a void context, gcc 4 generates an annoying
> warning.

Annoying indeed.

> > mm.h:
> > #define shm_lock(a, b) empty_int()
> > 
> > The typechecking is nice in theory, but in practice I don't think it
> > really makes a difference for stubbing things out.

I'm with Matt on the typechecking here, and at first liked his proposal;
but then dreaded a long line of empty_int_0(), empty_long_minus1(), ...
I suppose we could pass the return value as argument, but I rather lose
interest...

> Depends if you end up with "blah is unused" warnings instead.  It's
> all round _far_ safer to use the inline function method from that
> point of view.
> 
> Not that I particularly care, I just wanted to squash some of the
> rediculous number of warnings in the kernel and decided to hit the
> easy ones.  However, they're turning out to be real pigs instead. 8(

I have nothing constructive suggest, and withdraw my objection to your
patch; though I do hope someone else comes up with a brilliant idea.
Or, does the next version of gcc decide it was all a wrong turning?

Hugh