Re: [Chicken-hackers] [PATCH] Small improvement in Make's handling of variables, and a question about other common variables

[Peter Bex]

On Fri, Jun 13, 2014 at 10:14:51AM +0200, Felix Winkelmann wrote:
> >> It might not be the best way but works so far. I'm no sure in particular
> >> about -fno-strict-aliasing and -fwrapv. Maybe allowing user to override
> >> these will break something subtly.
> > 
> > Those two are a constant source of frustration :(  I think we can best
> > ignore them for now, as they're causing trouble either way: even providing
> > them by default in the platform Makefiles can be problematic (see Haiku).
> 
> Please note that these two options are required. I had cases where
> strict aliasing caused code to fail and -fwrapv disables some
> questionable optimizations with regard to signed integer overflow. C
> compilers get more and more aggressive, cutting corners wherever
> possible by exploiting undefined (but not necessarily unreaasonable)
> behaviour.

Thanks for pointing this out.  I didn't mean to suggest we should
remove them, just that they're not very relevant to our decision
regarding what to do with the variable names.  But on the other hand,
they might be.

We could always append them to CFLAGS from something like CHICKENCFLAGS
or some such.  That would ensure the generic CFLAGS are taken into
account and CHICKEN's important ones are added to it.  In any case,
if we decide to change this, we'll have to tread very carefully here.

Cheers,
Peter
-- 
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